WorldWideScience

Sample records for spatial trends studied

  1. Spatial correlation in precipitation trends in the Brazilian Amazon

    Science.gov (United States)

    Buarque, Diogo Costa; Clarke, Robin T.; Mendes, Carlos Andre Bulhoes

    2010-06-01

    A geostatistical analysis of variables derived from Amazon daily precipitation records (trends in annual precipitation totals, trends in annual maximum precipitation accumulated over 1-5 days, trend in length of dry spell, trend in number of wet days per year) gave results that are consistent with those previously reported. Averaged over the Brazilian Amazon region as a whole, trends in annual maximum precipitations were slightly negative, the trend in the length of dry spell was slightly positive, and the trend in the number of wet days in the year was slightly negative. For trends in annual maximum precipitation accumulated over 1-5 days, spatial correlation between trends was found to extend up to a distance equivalent to at least half a degree of latitude or longitude, with some evidence of anisotropic correlation. Time trends in annual precipitation were found to be spatially correlated up to at least ten degrees of separation, in both W-E and S-N directions. Anisotropic spatial correlation was strongly evident in time trends in length of dry spell with much stronger evidence of spatial correlation in the W-E direction, extending up to at least five degrees of separation, than in the S-N. Because the time trends analyzed are shown to be spatially correlated, it is argued that methods at present widely used to test the statistical significance of climate trends over time lead to erroneous conclusions if spatial correlation is ignored, because records from different sites are assumed to be statistically independent.

  2. Spatial pattern and temporal trend of mortality due to tuberculosis

    Directory of Open Access Journals (Sweden)

    Ana Angélica Rêgo de Queiroz

    2018-05-01

    Full Text Available ABSTRACT Objectives: To describe the epidemiological profile of mortality due to tuberculosis (TB, to analyze the spatial pattern of these deaths and to investigate the temporal trend in mortality due to tuberculosis in Northeast Brazil. Methods: An ecological study based on secondary mortality data. Deaths due to TB were included in the study. Descriptive statistics were calculated and gross mortality rates were estimated and smoothed by the Local Empirical Bayesian Method. Prais-Winsten’s regression was used to analyze the temporal trend in the TB mortality coefficients. The Kernel density technique was used to analyze the spatial distribution of TB mortality. Results: Tuberculosis was implicated in 236 deaths. The burden of tuberculosis deaths was higher amongst males, single people and people of mixed ethnicity, and the mean age at death was 51 years. TB deaths were clustered in the East, West and North health districts, and the tuberculosis mortality coefficient remained stable throughout the study period. Conclusions: Analyses of the spatial pattern and temporal trend in mortality revealed that certain areas have higher TB mortality rates, and should therefore be prioritized in public health interventions targeting the disease.

  3. A Study on Environmental Research Trends Using Text-Mining Method - Focus on Spatial information and ICT -

    Science.gov (United States)

    Lee, M. J.; Oh, K. Y.; Joung-ho, L.

    2016-12-01

    Recently there are many research about analysing the interaction between entities by text-mining analysis in various fields. In this paper, we aimed to quantitatively analyse research-trends in the area of environmental research relating either spatial information or ICT (Information and Communications Technology) by Text-mining analysis. To do this, we applied low-dimensional embedding method, clustering analysis, and association rule to find meaningful associative patterns of key words frequently appeared in the articles. As the authors suppose that KCI (Korea Citation Index) articles reflect academic demands, total 1228 KCI articles that have been published from 1996 to 2015 were reviewed and analysed by Text-mining method. First, we derived KCI articles from NDSL(National Discovery for Science Leaders) site. And then we pre-processed their key-words elected from abstract and then classified those in separable sectors. We investigated the appearance rates and association rule of key-words for articles in the two fields: spatial-information and ICT. In order to detect historic trends, analysis was conducted separately for the four periods: 1996-2000, 2001-2005, 2006-2010, 2011-2015. These analysis were conducted with the usage of R-software. As a result, we conformed that environmental research relating spatial information mainly focused upon such fields as `GIS(35%)', `Remote-Sensing(25%)', `environmental theme map(15.7%)'. Next, `ICT technology(23.6%)', `ICT service(5.4%)', `mobile(24%)', `big data(10%)', `AI(7%)' are primarily emerging from environmental research relating ICT. Thus, from the analysis results, this paper asserts that research trends and academic progresses are well-structured to review recent spatial information and ICT technology and the outcomes of the analysis can be an adequate guidelines to establish environment policies and strategies. KEY WORDS: Big data, Test-mining, Environmental research, Spatial-information, ICT Acknowledgements: The

  4. Spatial variability and trends of the rain intensity over Greece

    Science.gov (United States)

    Kambezidis, H. D.; Larissi, I. K.; Nastos, P. T.; Paliatsos, A. G.

    2010-07-01

    In this study, the spatial and temporal variability of the mean annual rain intensity in Greece are examined during a 41-year period (1962-2002). The meteorological datasets concern monthly rain amounts (mm) and the respective monthly durations (h) recorded at thirty two meteorological stations of the Hellenic National Meteorological Service, which are uniformly distributed on Greek territory, in order to calculate the mean monthly rain intensity. All the rain time series used in the analysis were tested by the application of the short-cut Bartlett test of homogeneity. The spatial distribution of the mean annual rain intensity is studied using the Kriging interpolation method, while the temporal variability, concerning the mean annual rain intensity trends along with their significance (Mann-Kendall test), is analysed. The findings of the analysis show that statistically significant negative trends (95% confidence level) appear mainly in the west sub-regions of Greece, while statistically significant positive trends (95% confidence level) appear in the wider area of Athens and the complex of Cyclades Islands. Further analysis concerning the seasonal rain intensity is needed, because there are different seasonal patterns, taking into account that, convective rain in Greece occurs mainly within the summer season.

  5. Spatial trends of polybrominated diphenyl ether (PBDE) congeners

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spatial trends of polybrominated diphenyl ether (PBDE) congeners were analyzed in young of the year bluefish collected along the U.S. Atlantic coastline from...

  6. Spatial patterns of March and September streamflow trends in Pacific Northwest Streams, 1958-2008

    Science.gov (United States)

    Chang, Heejun; Jung, Il-Won; Steele, Madeline; Gannett, Marshall

    2012-01-01

    Summer streamflow is a vital water resource for municipal and domestic water supplies, irrigation, salmonid habitat, recreation, and water-related ecosystem services in the Pacific Northwest (PNW) in the United States. This study detects significant negative trends in September absolute streamflow in a majority of 68 stream-gauging stations located on unregulated streams in the PNW from 1958 to 2008. The proportion of March streamflow to annual streamflow increases in most stations over 1,000 m elevation, with a baseflow index of less than 50, while absolute March streamflow does not increase in most stations. The declining trends of September absolute streamflow are strongly associated with seven-day low flow, January–March maximum temperature trends, and the size of the basin (19–7,260 km2), while the increasing trends of the fraction of March streamflow are associated with elevation, April 1 snow water equivalent, March precipitation, center timing of streamflow, and October–December minimum temperature trends. Compared with ordinary least squares (OLS) estimated regression models, spatial error regression and geographically weighted regression (GWR) models effectively remove spatial autocorrelation in residuals. The GWR model results show spatial gradients of local R 2 values with consistently higher local R 2 values in the northern Cascades. This finding illustrates that different hydrologic landscape factors, such as geology and seasonal distribution of precipitation, also influence streamflow trends in the PNW. In addition, our spatial analysis model results show that considering various geographic factors help clarify the dynamics of streamflow trends over a large geographical area, supporting a spatial analysis approach over aspatial OLS-estimated regression models for predicting streamflow trends. Results indicate that transitional rain–snow surface water-dominated basins are likely to have reduced summer streamflow under warming scenarios

  7. Spatial variations of summer precipitation trends in South Korea, 1973-2005

    International Nuclear Information System (INIS)

    Chang, Heejun; Kwon, Won-Tae

    2007-01-01

    We have investigated the spatial patterns of trends in summer precipitation amount, intensity, and heavy precipitation for South Korea between 1973 and 2005. All stations show increasing trends in precipitation amount during the summer months, with the highest percentage of significant increase in June precipitation for the northern and central western part of South Korea. There is a significant increase in August precipitation for stations in the southeastern part of South Korea. Only a few stations exhibited significant upward trends in September precipitation. There is a weak to moderate spatial autocorrelation with the highest Moran's I value in June precipitation amount and August precipitation intensity. The number of days with daily precipitation exceeding 50 and 30 mm during the summer has increased at all stations. Observed trends are likely to be associated with changes in large-scale atmospheric circulation, sea surface temperature anomalies, and orography, but detailed causes of these trends need further investigation

  8. Quantifying spatial and temporal trends in beach-dune volumetric changes using spatial statistics

    Science.gov (United States)

    Eamer, Jordan B. R.; Walker, Ian J.

    2013-06-01

    Spatial statistics are generally underutilized in coastal geomorphology, despite offering great potential for identifying and quantifying spatial-temporal trends in landscape morphodynamics. In particular, local Moran's Ii provides a statistical framework for detecting clusters of significant change in an attribute (e.g., surface erosion or deposition) and quantifying how this changes over space and time. This study analyzes and interprets spatial-temporal patterns in sediment volume changes in a beach-foredune-transgressive dune complex following removal of invasive marram grass (Ammophila spp.). Results are derived by detecting significant changes in post-removal repeat DEMs derived from topographic surveys and airborne LiDAR. The study site was separated into discrete, linked geomorphic units (beach, foredune, transgressive dune complex) to facilitate sub-landscape scale analysis of volumetric change and sediment budget responses. Difference surfaces derived from a pixel-subtraction algorithm between interval DEMs and the LiDAR baseline DEM were filtered using the local Moran's Ii method and two different spatial weights (1.5 and 5 m) to detect statistically significant change. Moran's Ii results were compared with those derived from a more spatially uniform statistical method that uses a simpler student's t distribution threshold for change detection. Morphodynamic patterns and volumetric estimates were similar between the uniform geostatistical method and Moran's Ii at a spatial weight of 5 m while the smaller spatial weight (1.5 m) consistently indicated volumetric changes of less magnitude. The larger 5 m spatial weight was most representative of broader site morphodynamics and spatial patterns while the smaller spatial weight provided volumetric changes consistent with field observations. All methods showed foredune deflation immediately following removal with increased sediment volumes into the spring via deposition at the crest and on lobes in the lee

  9. Mapping Patterns and Trends in the Spatial Availability of Alcohol Using Low-Level Geographic Data: A Case Study in England 2003-2013.

    Science.gov (United States)

    Angus, Colin; Holmes, John; Maheswaran, Ravi; Green, Mark A; Meier, Petra; Brennan, Alan

    2017-04-12

    Much literature examines the relationship between the spatial availability of alcohol and alcohol-related harm. This study aims to address an important gap in this evidence by using detailed outlet data to examine recent temporal trends in the sociodemographic distribution of spatial availability for different types of alcohol outlet in England. Descriptive analysis of measures of alcohol outlet density and proximity using extremely high resolution market research data stratified by outlet type and quintiles of area-level deprivation from 2003, 2007, 2010 and 2013 was undertaken and hierarchical linear growth models fitted to explore the significance of socioeconomic differences. We find that overall availability of alcohol changed very little from 2003 to 2013 (density +1.6%), but this conceals conflicting trends by outlet type and area-level deprivation. Mean on-trade density has decreased substantially (-2.2 outlets within 1 km (Inter-Quartile Range (IQR) -3-0), although access to restaurants has increased (+1.0 outlets (IQR 0-1)), while off-trade access has risen substantially (+2.4 outlets (IQR 0-3)). Availability is highest in the most deprived areas ( p trends in the spatial availability of alcohol. There are significant variations in these trends by outlet type and deprivation level which may have important implications for health inequalities and public health policy.

  10. Modelling firm heterogeneity with spatial 'trends'

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento, C. [North Dakota State University, Fargo, ND (United States). Dept. of Agricultural Business & Applied Economics

    2004-04-15

    The hypothesis underlying this article is that firm heterogeneity can be captured by spatial characteristics of the firm (similar to the inclusion of a time trend in time series models). The hypothesis is examined in the context of modelling electric generation by coal powered plants in the presence of firm heterogeneity.

  11. Spatial distribution of unidirectional trends in temperature and temperature extremes in Pakistan

    Science.gov (United States)

    Khan, Najeebullah; Shahid, Shamsuddin; Ismail, Tarmizi bin; Wang, Xiao-Jun

    2018-06-01

    Pakistan is one of the most vulnerable countries of the world to temperature extremes due to its predominant arid climate and geographic location in the fast temperature rising zone. Spatial distribution of the trends in annual and seasonal temperatures and temperature extremes over Pakistan has been assessed in this study. The gauge-based gridded daily temperature data of Berkeley Earth Surface Temperature (BEST) having a spatial resolution of 1° × 1° was used for the assessment of trends over the period 1960-2013 using modified Mann-Kendall test (MMK), which can discriminate the multi-decadal oscillatory variations from secular trends. The results show an increase in the annual average of daily maximum and minimum temperatures in 92 and 99% area of Pakistan respectively at 95% level of confidence. The annual temperature is increasing faster in southern high-temperature region compared to other parts of the country. The minimum temperature is rising faster (0.17-0.37 °C/decade) compared to maximum temperature (0.17-0.29 °C/decade) and therefore declination of diurnal temperature range (DTR) (- 0.15 to - 0.08 °C/decade) in some regions. The annual numbers of both hot and cold days are increasing in whole Pakistan except in the northern sub-Himalayan region. Heat waves are on the rise, especially in the hot Sindh plains and the Southern coastal region, while the cold waves are becoming lesser in the northern cold region. Obtained results contradict with the findings of previous studies on temperature trends, which indicate the need for reassessment of climatic trends in Pakistan using the MMK test to understand the anthropogenic impacts of climate change.

  12. Long term spatial and temporal rainfall trends and homogeneity analysis in Wainganga basin, Central India

    Directory of Open Access Journals (Sweden)

    Arun Kumar Taxak

    2014-08-01

    Full Text Available Gridded rainfall data of 0.5×0.5° resolution (CRU TS 3.21 was analysed to study long term spatial and temporal trends on annual and seasonal scales in Wainganga river basin located in Central India during 1901–2012. After testing the presence of autocorrelation, Mann–Kendall (Modified Mann–Kendall test was applied to non-auto correlated (auto correlated series to detect the trends in rainfall data. Theil and Sen׳s slope estimator test was used for finding the magnitude of change over a time period. For detecting the most probable change year, Pettitt–Mann–Whitney test was applied. The Rainfall series was then divided into two partial duration series for finding changes in trends before and after the change year. Arc GIS was used to explore spatial patterns of the trends over the entire basin. Though most of the grid points shows a decreasing trend in annual rainfall, only seven grids has a significant decreasing trend during 1901–2012. On the basis of seasonal trend analysis, non-significant increasing trend is observed only in post monsoon season while seven grid points show significant decreasing trend in monsoon rainfall and non-significant in pre-monsoon and winter rainfall over the last 112 years. During the study period, overall a 8.45% decrease in annual rainfall is estimated. The most probable year of change was found to be 1948 in annual and monsoonal rainfall. There is an increasing rainfall trend in the basin during the period 1901–1948, which is reversed during the period 1949–2012 resulting in decreasing rainfall trend in the basin. Homogeneous trends in annual and seasonal rainfall over a grid points is exhibited in the basin by van Belle and Hughes׳ homogeneity trend test.

  13. Statistical analysis of long term spatial and temporal trends of ...

    Indian Academy of Sciences (India)

    Statistical analysis of long term spatial and temporal trends of temperature ... CGCM3; HadCM3; modified Mann–Kendall test; statistical analysis; Sutlej basin. ... Water Resources Systems Division, National Institute of Hydrology, Roorkee 247 ...

  14. Spatial and temporal trends of selected trace elements in liver tissue from polar bears (Ursus maritimus) from Alaska, Canada and Greenland.

    Science.gov (United States)

    Routti, Heli; Letcher, Robert J; Born, Erik W; Branigan, Marsha; Dietz, Rune; Evans, Thomas J; Fisk, Aaron T; Peacock, Elizabeth; Sonne, Christian

    2011-08-01

    Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg(2+)-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements.

  15. Spatial and temporal trends of selected trace elements in liver tissue from polar bears (Ursus maritimus) from Alaska, Canada and Greenland

    Science.gov (United States)

    Routti, H.; Letcher, R.J.; Born, E.W.; Branigan, M.; Dietz, R.; Evans, T.J.; Fisk, A.T.; Peacock, E.; Sonne, C.

    2011-01-01

    Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg 2+-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements. ?? 2011 The Royal Society of Chemistry.

  16. Spatial and Temporal Trends of Snowfall in Central New York - A Lake Effect Dominated Region

    Science.gov (United States)

    Hartnett, Justin Joseph

    Central New York is located in one of the snowiest regions in the United States, with the city of Syracuse, New York the snowiest metropolis in the nation. Snowfall in the region generally begins in mid-November and lasts until late-March. Snow accumulation occurs from a multitude of conditions: frontal systems, mid-latitude cyclones, Nor'easters, and most notably lake-effect storms. Lake effect snowfall (LES) is a difficult parameter to forecast due to the isolated and highly variable nature of the storm. Consequently, studies have attempted to determine changes in snowfall for lake-effect dominated regions. Annual snowfall patterns are of particular concern as seasonal snowfall totals are vital for water resources, winter businesses, agriculture, government and state agencies, and much more. Through the use of snowfall, temperature, precipitation, and location data from the National Weather Service's Cooperative Observer Program (COOP), spatial and temporal changes in snowfall for Central New York were determined. In order to determine climatic changes in snowfall, statistical analyses were performed (i.e. least squares estimation, correlations, principal component analyses, etc.) and spatial maps analyzed. Once snowfall trends were determined, factors influencing the trends were examined. Long-term snowfall trends for CNY were positive for original stations (˜0.46 +/- 0.20 in. yr -1) and homogenously filtered stations (0.23 +/- 0.20 in. yr -1). However, snowfall trends for shorter time-increments within the long-term period were not consistent, as positive, negative, and neutral trends were calculated. Regional differences in snowfall trends were observed for CNY as typical lake-effect areas (northern counties, the Tug Hill Plateau and the Southern Hills) experienced larger snowfall trends than areas less dominated by LES. Typical lake-effect months (December - February) experienced the greatest snowfall trend in CNY compared to other winter months. The

  17. Estimating temporal trend in the presence of spatial complexity: a Bayesian hierarchical model for a wetland plant population undergoing restoration.

    Directory of Open Access Journals (Sweden)

    Thomas J Rodhouse

    Full Text Available Monitoring programs that evaluate restoration and inform adaptive management are important for addressing environmental degradation. These efforts may be well served by spatially explicit hierarchical approaches to modeling because of unavoidable spatial structure inherited from past land use patterns and other factors. We developed bayesian hierarchical models to estimate trends from annual density counts observed in a spatially structured wetland forb (Camassia quamash [camas] population following the cessation of grazing and mowing on the study area, and in a separate reference population of camas. The restoration site was bisected by roads and drainage ditches, resulting in distinct subpopulations ("zones" with different land use histories. We modeled this spatial structure by fitting zone-specific intercepts and slopes. We allowed spatial covariance parameters in the model to vary by zone, as in stratified kriging, accommodating anisotropy and improving computation and biological interpretation. Trend estimates provided evidence of a positive effect of passive restoration, and the strength of evidence was influenced by the amount of spatial structure in the model. Allowing trends to vary among zones and accounting for topographic heterogeneity increased precision of trend estimates. Accounting for spatial autocorrelation shifted parameter coefficients in ways that varied among zones depending on strength of statistical shrinkage, autocorrelation and topographic heterogeneity--a phenomenon not widely described. Spatially explicit estimates of trend from hierarchical models will generally be more useful to land managers than pooled regional estimates and provide more realistic assessments of uncertainty. The ability to grapple with historical contingency is an appealing benefit of this approach.

  18. Spatial trends in tourism within South Africa: The expected and the ...

    African Journals Online (AJOL)

    Dave McKelly

    spatial trends and impacts of the tourism sector in local economies in South Africa. .... on local economies, in particular by generating economic and social development in marginal ..... other metros relates to the availability of medical facilities.

  19. Spatial trends in tourism within South Africa: The expected and the ...

    African Journals Online (AJOL)

    Spatial trends in tourism within South Africa: The expected and the surprising. ... of its distribution and in relation to its potential local impacts across the country. ... The discussion of the tourism space economy is based on an analysis of a local ...

  20. Spatial patterns and secular trends in human leishmaniasis incidence in Morocco between 2003 and 2013.

    Science.gov (United States)

    Sadeq, Mina

    2016-05-11

    Few studies on spatial patterns or secular trends in human leishmanias have been conducted in Morocco. This study aimed to examine spatial patterns and trends associated with the human leishmaniasis incidence rate (HLIR) at the province/prefecture level between 2003 and 2013 in Morocco. Only the available published country data on the HLIR between 2003 and 2013, from the open access files of the Ministry of Health, were used. Secular trends were examined using Kendall's rank correlation. An exploratory spatial data analysis was also conducted to examine the spatial autocorrelation (Global Moran's I and local indicator of spatial association [LISA]), and spatial diffusion at the province/prefecture level. The influence of various covariates (poverty rate, vulnerability rate, population density, and urbanization) on the HLIR was tested via spatial regression (ordinary least squares regression). At the country level, no secular variation was observed. Poisson annual incidence rate estimates were 13 per 100 000 population (95 % CI = 12.9-13.1) for cutaneous leishmaniasis (CL) and 0.4 per 100 000 population (95 % CI = 0.4-0.5) for visceral leishmaniasis (VL). The available data on HLIR were based on combined CL and VL cases, however, as the CL cases totally outnumbered the VL ones, HLIR may be considered as CL incidence rate. At the provincial level, a secular increase in the incidence rate was observed in Al Hoceima (P = 0.008), Taounate (P = 0.04), Larache (P = 0.002), Tétouan (P = 0.0003), Khenifra (P = 0.008), Meknes (P = 0.03), and El Kelaa (P = 0.0007), whereas a secular decrease was observed only in the Chichaoua province (P = 0.006). Even though increased or decreased rate was evident in these provinces, none of them showed clustering of leishmaniasis incidence. Significant spatial clusters of high leishmaniasis incidence were located in the northeastern part of Morocco, while spatial clusters of low leishmaniasis

  1. Modelling spatial trends in sorghum breeding field trials using a two-dimensional P-spline mixed model

    NARCIS (Netherlands)

    J.G. Velazco (Julio G.); M.X. Rodríguez-Álvarez (María Xosé); M.P. Boer (Martin); D.R. Jordan (David R.); P.H.C. Eilers (Paul); M. Malosetti (Marcos); F. van Eeuwijk (Fred)

    2017-01-01

    markdownabstract_Key message: A flexible and user-friendly spatial method called SpATS performed comparably to more elaborate and trial-specific spatial models in a series of sorghum breeding trials._ __Abstract:__ Adjustment for spatial trends in plant breeding field trials is essential for

  2. Modelling spatial trends in sorghum breeding field trials using a two-dimensional P-spline mixed model

    NARCIS (Netherlands)

    Velazco, Julio G.; Rodríguez-Álvarez, María Xosé; Boer, Martin P.; Jordan, David R.; Eilers, Paul H.C.; Malosetti, Marcos; Eeuwijk, van Fred A.

    2017-01-01

    Key message: A flexible and user-friendly spatial method called SpATS performed comparably to more elaborate and trial-specific spatial models in a series of sorghum breeding trials. Abstract: Adjustment for spatial trends in plant breeding field trials is essential for efficient evaluation and

  3. Temporal and Spatial Trend of Climate Variability in Vietnam

    OpenAIRE

    Duc Luong Nguyen

    2014-01-01

    Vietnam’s long coastline, geographic location, and diverse topography and climates contribute to its being one of the most hazard-prone countries of the Asia-Pacific region. Given that a high proportion of the country’s population and economic assets are located in coastal lowlands and deltas, Vietnam has been ranked among the five countries likely to be most affected by global climate change. This paper aims at providing a short overview on the temporal and spatial trends of climate variabil...

  4. Hair mercury levels in Amazonian populations: spatial distribution and trends

    Directory of Open Access Journals (Sweden)

    Barbieri Flavia L

    2009-12-01

    Full Text Available Abstract Background Mercury is present in the Amazonian aquatic environments from both natural and anthropogenic sources. As a consequence, many riverside populations are exposed to methylmercury, a highly toxic organic form of mercury, because of their intense fish consumption. Many studies have analysed this exposure from different approaches since the early nineties. This review aims to systematize the information in spatial distribution, comparing hair mercury levels by studied population and Amazonian river basin, looking for exposure trends. Methods The reviewed papers were selected from scientific databases and online libraries. We included studies with a direct measure of hair mercury concentrations in a sample size larger than 10 people, without considering the objectives, approach of the study or mercury speciation. The results are presented in tables and maps by river basin, displaying hair mercury levels and specifying the studied population and health impact, if any. Results The majority of the studies have been carried out in communities from the central Amazonian regions, particularly on the Tapajós River basin. The results seem quite variable; hair mercury means range from 1.1 to 34.2 μg/g. Most studies did not show any significant difference in hair mercury levels by gender or age. Overall, authors emphasized fish consumption frequency as the main risk factor of exposure. The most studied adverse health effect is by far the neurological performance, especially motricity. However, it is not possible to conclude on the relation between hair mercury levels and health impact in the Amazonian situation because of the relatively small number of studies. Conclusions Hair mercury levels in the Amazonian regions seem to be very heterogenic, depending on several factors. There is no obvious spatial trend and there are many areas that have never been studied. Taking into account the low mercury levels currently handled as acceptable, the

  5. Spatial trends in tourism within South Africa: The expected and the surprising

    CSIR Research Space (South Africa)

    Mc Kelly, David H

    2017-08-01

    Full Text Available The aim is to provide an indication of the value of such comparative analyses of the spatial trends and impacts of the tourism sector in local economies in South Africa. The discussion of the tourism space economy is based on an analysis of a local...

  6. Reevaluation of Stratospheric Ozone Trends From SAGE II Data Using a Simultaneous Temporal and Spatial Analysis

    Science.gov (United States)

    Damadeo, R. P.; Zawodny, J. M.; Thomason, L. W.

    2014-01-01

    This paper details a new method of regression for sparsely sampled data sets for use with time-series analysis, in particular the Stratospheric Aerosol and Gas Experiment (SAGE) II ozone data set. Non-uniform spatial, temporal, and diurnal sampling present in the data set result in biased values for the long-term trend if not accounted for. This new method is performed close to the native resolution of measurements and is a simultaneous temporal and spatial analysis that accounts for potential diurnal ozone variation. Results show biases, introduced by the way data is prepared for use with traditional methods, can be as high as 10%. Derived long-term changes show declines in ozone similar to other studies but very different trends in the presumed recovery period, with differences up to 2% per decade. The regression model allows for a variable turnaround time and reveals a hemispheric asymmetry in derived trends in the middle to upper stratosphere. Similar methodology is also applied to SAGE II aerosol optical depth data to create a new volcanic proxy that covers the SAGE II mission period. Ultimately this technique may be extensible towards the inclusion of multiple data sets without the need for homogenization.

  7. Spatial and Temporal Trends in PM2.5 Organic and Elemental Carbon across the United States

    Directory of Open Access Journals (Sweden)

    J. L. Hand

    2013-01-01

    Full Text Available The rural/remote IMPROVE network (Interagency Monitoring of Protected Visual Environments and the Environmental Protection Agency's urban Chemical Speciation Network have measured PM2.5 organic (OC and elemental carbon (EC since 1989 and 2000, respectively. We aggregated OC and EC data from 2007 to 2010 at over 300 sites from both networks in order to characterize the spatial and seasonal patterns in rural and urban carbonaceous aerosols. The spatial extent of OC and EC was more regional in the eastern United States relative to more localized concentrations in the West. The highest urban impacts of OC and EC relative to background concentrations occurred in the West during fall and winter. Urban and rural carbonaceous aerosols experienced a large (although opposite range in seasonality in the West compared to a much lower seasonal variability in the East. Long-term (1990–2010 trend analyses indicated a widespread decrease in rural TC (TC = OC + EC across the country, with positive, though insignificant, trends in the summer and fall in the West. Short-term trends indicated that urban and rural TC concentrations have both decreased since 2000, with the strongest and more spatially homogeneous urban and rural trends in the West relative to the East.

  8. Spatial Change as Drivers of Risk and Vulnerability in South Africa: Spatial trends in the 3 metropolitan cities of Gauteng

    CSIR Research Space (South Africa)

    Pieterse, Amy

    2016-07-01

    Full Text Available Urban spatial change trends manifest most noticeably in Gauteng. This not only confirms perceptions about metros as increasingly being the spaces where the future of South Africa's youth will be determined, but also once again rings the alarm bells...

  9. Extent of Night Warming and Spatially Heterogeneous Cloudiness Differentiate Temporal Trend of Greenness in Mountainous Tropics in the New Century.

    Science.gov (United States)

    Yu, Mei; Gao, Qiong; Gao, Chunxiao; Wang, Chao

    2017-01-25

    Tropical forests have essential functions in global C dynamics but vulnerable to changes in land cover land use (LCLUC) and climate. The tropics of Caribbean are experiencing warming and drying climate and diverse LCLUC. However, large-scale studies to detect long-term trends of C and mechanisms behind are still rare. Using MODIS Enhanced Vegetation Index (EVI), we investigated greenness trend in the Greater Antilles Caribbean during 2000-2015, and analyzed trend of vegetation patches without LCLUC to give prominence to climate impacts. We hypothesized that night warming and heavy cloudiness would reduce EVI in this mountainous tropical region. Over the 15 years, EVI decreased significantly in Jamaica, Haiti, Dominican Republic, and Puerto Rico, but increased in Cuba partly due to its strong reforestation. Haiti had the largest decreasing trend because of continuous deforestation for charcoals. After LCLUC was excluded, EVI trend still varied greatly, decreasing in the windward but increasing in the leeward of Puerto Rico. Nighttime warming reinforced by spatially heterogeneous cloudiness was found to significantly and negatively correlate with EVI trend, and explained the spatial pattern of the latter. Although cooled daytime and increased rainfall might enhance EVI, nighttime warming dominated the climate impacts and differentiated the EVI trend.

  10. Modeling a secular trend by Monte Carlo simulation of height biased migration in a spatial network.

    Science.gov (United States)

    Groth, Detlef

    2017-04-01

    Background: In a recent Monte Carlo simulation, the clustering of body height of Swiss military conscripts within a spatial network with characteristic features of the natural Swiss geography was investigated. In this study I examined the effect of migration of tall individuals into network hubs on the dynamics of body height within the whole spatial network. The aim of this study was to simulate height trends. Material and methods: Three networks were used for modeling, a regular rectangular fishing net like network, a real world example based on the geographic map of Switzerland, and a random network. All networks contained between 144 and 148 districts and between 265-307 road connections. Around 100,000 agents were initially released with average height of 170 cm, and height standard deviation of 6.5 cm. The simulation was started with the a priori assumption that height variation within a district is limited and also depends on height of neighboring districts (community effect on height). In addition to a neighborhood influence factor, which simulates a community effect, body height dependent migration of conscripts between adjacent districts in each Monte Carlo simulation was used to re-calculate next generation body heights. In order to determine the direction of migration for taller individuals, various centrality measures for the evaluation of district importance within the spatial network were applied. Taller individuals were favored to migrate more into network hubs, backward migration using the same number of individuals was random, not biased towards body height. Network hubs were defined by the importance of a district within the spatial network. The importance of a district was evaluated by various centrality measures. In the null model there were no road connections, height information could not be delivered between the districts. Results: Due to the favored migration of tall individuals into network hubs, average body height of the hubs, and later

  11. Multivariate and spatial statistical analysis of Callovo-Oxfordian physical properties from lab and borehole logs data: towards a characterization of lateral and vertical spatial trends in the Meuse/Haute-Marne transposition zone

    International Nuclear Information System (INIS)

    Garcia, M.H.; Rabaute, A.; Yven, B.; Guillemot, D.

    2010-01-01

    Document available in extended abstract form only. The geological exploration of the Meuse/Haute-Marne area began in 1994. Several boreholes were drilled, and the Callovo-Oxfordian argillite, thought to become a potential storage formation, were cored and logged. 2D and 3D seismic surveys were completed, as well as geological field observations, and an underground research laboratory was created. A 250 km 2 -wide Transposition Zone was delimited, which was subject to further investigations in 2007 and 2008, including another series of coring and logging in four additional boreholes, and a tighter 2D seismic survey. The main objective of this study was to improve the knowledge of the spatial variability of geological and physical properties of the Callovo-Oxfordian formation. The paper focuses on the three following aspects of the study to present and discuss the methods that have been used and the results that have been obtained: - Use of well-log data to identify equivalent homogeneous log-units on the boreholes. - Relating log attributes to physical properties of argillites measured on cores in laboratory. - Study of lateral and vertical spatial trends of selected physical properties across the Transposition Zone (TZ). To identify equivalent homogeneous log-units, a combination of Principal Component Analysis (PCA) and Fuzzy Cluster Analysis (FCA) was used. PCA was classically performed to reduce the number of variables to retain principal components gathering most of the original dataset variance. PCA was also used to identify isolated groups of correlated variables that could be associated to different properties of the formation. Then, FCA was applied to identify homogeneous log-units on the eight boreholes across the TZ. Well-logs data being much more numerous and better distributed along boreholes than lab data measured on rock samples, relations and correlations were sought between the two types of data to identify log attributes that were likely to provide

  12. Spatial and Temporal Streamflow Trends in Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Chen-Feng Yeh

    2015-02-01

    Full Text Available Streamflow is an important factor in the study of water resource management, floods, and droughts. Dramatic climate change has created extreme rainfall distributions, making the study of streamflow trends and variability even more crucial. In this study, the long-term streamflow data and trends recorded at gauging stations in Northern Taiwan are analyzed using the Mann-Kendall test. The data used for trend analysis are the average annual streamflow, the average seasonal streamflow, and the high and low flows. The slope trend is calculated using the Theil-Sen estimator. Finally, change point analysis is conducted using the Mann-Whitney-Pettit test and the cumulative deviation test to gain further information about the change points and to understand the changes in streamflow before and after the change points. The average annual streamflow of the 12 gauging stations in the study area is analyzed using the Mann-Kendall test. The results show that of the 12 gauging stations, only the Ximen Bridge Station in the Lanyang River basin show a significant downward streamflow trend. Results of the monthly and seasonal average streamflow analysis show that in the spring, 72.2% of the gauging stations showed upward streamflow trends, most of which were located in the Tamsui River and the Touqian River basins. The high and low flow data analysis shows that the Ximen Bridge Station was the only gauging station to feature a significant downward streamflow trend for both high and low flows. This distribution pattern provides valuable information for regional hydrological studies and water management.

  13. Characterizing the spatial variations and correlations of large rainstorms for landslide study

    Directory of Open Access Journals (Sweden)

    L. Gao

    2017-09-01

    Full Text Available Rainfall is the primary trigger of landslides in Hong Kong; hence, rainstorm spatial distribution is an important piece of information in landslide hazard analysis. The primary objective of this paper is to quantify spatial correlation characteristics of three landslide-triggering large storms in Hong Kong. The spatial maximum rolling rainfall is represented by a rotated ellipsoid trend surface and a random field of residuals. The maximum rolling 4, 12, 24, and 36 h rainfall amounts of these storms are assessed via surface trend fitting, and the spatial correlation of the detrended residuals is determined through studying the scales of fluctuation along eight directions. The principal directions of the surface trend are between 19 and 43°, and the major and minor axis lengths are 83–386 and 55–79 km, respectively. The scales of fluctuation of the residuals are found between 5 and 30 km. The spatial distribution parameters for the three large rainstorms are found to be similar to those for four ordinary rainfall events. The proposed rainfall spatial distribution model and parameters help define the impact area, rainfall intensity and local topographic effects for landslide hazard evaluation in the future.

  14. Indian Summer Monsoon Rainfall: Implications of Contrasting Trends in the Spatial Variability of Means and Extremes

    Science.gov (United States)

    Ghosh, Subimal; Vittal, H.; Sharma, Tarul; Karmakar, Subhankar; Kasiviswanathan, K. S.; Dhanesh, Y.; Sudheer, K. P.; Gunthe, S. S.

    2016-01-01

    India’s agricultural output, economy, and societal well-being are strappingly dependent on the stability of summer monsoon rainfall, its variability and extremes. Spatial aggregate of intensity and frequency of extreme rainfall events over Central India are significantly increasing, while at local scale they are spatially non-uniform with increasing spatial variability. The reasons behind such increase in spatial variability of extremes are poorly understood and the trends in mean monsoon rainfall have been greatly overlooked. Here, by using multi-decadal gridded daily rainfall data over entire India, we show that the trend in spatial variability of mean monsoon rainfall is decreasing as exactly opposite to that of extremes. The spatial variability of extremes is attributed to the spatial variability of the convective rainfall component. Contrarily, the decrease in spatial variability of the mean rainfall over India poses a pertinent research question on the applicability of large scale inter-basin water transfer by river inter-linking to address the spatial variability of available water in India. We found a significant decrease in the monsoon rainfall over major water surplus river basins in India. Hydrological simulations using a Variable Infiltration Capacity (VIC) model also revealed that the water yield in surplus river basins is decreasing but it is increasing in deficit basins. These findings contradict the traditional notion of dry areas becoming drier and wet areas becoming wetter in response to climate change in India. This result also calls for a re-evaluation of planning for river inter-linking to supply water from surplus to deficit river basins. PMID:27463092

  15. Indian Summer Monsoon Rainfall: Implications of Contrasting Trends in the Spatial Variability of Means and Extremes.

    Directory of Open Access Journals (Sweden)

    Subimal Ghosh

    Full Text Available India's agricultural output, economy, and societal well-being are strappingly dependent on the stability of summer monsoon rainfall, its variability and extremes. Spatial aggregate of intensity and frequency of extreme rainfall events over Central India are significantly increasing, while at local scale they are spatially non-uniform with increasing spatial variability. The reasons behind such increase in spatial variability of extremes are poorly understood and the trends in mean monsoon rainfall have been greatly overlooked. Here, by using multi-decadal gridded daily rainfall data over entire India, we show that the trend in spatial variability of mean monsoon rainfall is decreasing as exactly opposite to that of extremes. The spatial variability of extremes is attributed to the spatial variability of the convective rainfall component. Contrarily, the decrease in spatial variability of the mean rainfall over India poses a pertinent research question on the applicability of large scale inter-basin water transfer by river inter-linking to address the spatial variability of available water in India. We found a significant decrease in the monsoon rainfall over major water surplus river basins in India. Hydrological simulations using a Variable Infiltration Capacity (VIC model also revealed that the water yield in surplus river basins is decreasing but it is increasing in deficit basins. These findings contradict the traditional notion of dry areas becoming drier and wet areas becoming wetter in response to climate change in India. This result also calls for a re-evaluation of planning for river inter-linking to supply water from surplus to deficit river basins.

  16. The study for the Spatial Distribution Pattern of NDVI in the Western of Jilin Province

    Science.gov (United States)

    Yang, Shu-jie; Li, Xiao-dong; Yan, Shou-gang

    2018-02-01

    Using methods of spatial autocorrelation analysis and trend analysis, the paper studies the spatial distribution pattern of NDVI based on the GIMMS NDVI dataset (1998-2008), in Western Jilin. The maximum value for 15d is got through the method of MAX processing. Results show that: the NDVI in growing season shows a rising trend in western Jilin in 1998-2008. In the study area, the NDVI in Western Jilin shows positive spatial autocorrelation in the whole region, but the partial NDVI is apt to scattered distribution, which means the vegetation cover of Western Jilin is generally fragmental.

  17. TRENDS IN FLOODS AND LOW FLOWS IN THE UNITED STATES: IMPACT OF SPATIAL CORRELATION. (R824992,R826888)

    Science.gov (United States)

    Trends in flood and low flows in the US were evaluated using a regional average Kendall's S trend test at two spatial scales and over two timeframes. Field significance was assessed using a bootstrap methodology to account for the observed regional cross-correlation of streamflow...

  18. Migrant deaths at the Arizona-Mexico border: Spatial trends of a mass disaster.

    Science.gov (United States)

    Giordano, Alberto; Spradley, M Katherine

    2017-11-01

    Geographic Information Science (GIScience) technology has been used to document, investigate, and predict patterns that may be of utility in both forensic academic research and applied practice. In examining spatial and temporal trends of the mass disaster that is occurring along the U.S.-Mexico border, other researchers have highlighted predictive patterns for search and recovery efforts as well as water station placement. The purpose of this paper is to use previously collected spatial data of migrant deaths from Arizona to address issues of data uncertainty and data accuracy that affect our understanding of this phenomenon, including local and federal policies that impact the U.S.-Mexico border. The main objective of our study was to explore how the locations of migrant deaths have varied over time. Our results confirm patterns such as a lack of relationship between Border Patrol apprehensions and migrant deaths, as well as highlight new patterns such as the increased positional accuracy of migrant deaths recorded closer to the border. This paper highlights the importance of using positionally accurate data to detect spatio-temporal trends in forensic investigations of mass disasters: without qualitative and quantitative information concerning the accuracy of the data collected, the reliability of the results obtained remains questionable. We conclude by providing a set of guidelines for standardizing the collection and documentation of migrant remains at the U.S.-Mexico border. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Spatial and temporal trends and flow dynamics of glyphosate and other pesticides within an agricultural watershed in Argentina.

    Science.gov (United States)

    Pérez, Débora J; Okada, Elena; De Gerónimo, Eduardo; Menone, Mirta L; Aparicio, Virginia C; Costa, José L

    2017-12-01

    In the present study, we evaluated the spatial and temporal trends of current-use pesticides in surface water and sediments as well as their relationship with hydrological stream dynamics within the agricultural watershed of El Crespo stream (Buenos Aires Province, Argentina). We sampled 2 contrasting sites: site 1 (upstream), surrounded by agricultural lands, and site 2 (downstream), surrounded by natural grasslands. Most of the applied pesticides (glyphosate, 2,4-D, atrazine, tebuconazole, and imidacloprid) were detected at high frequencies in surface water samples at both sites. However, only glyphosate and aminomethylphosphonic acid (AMPA) were present at high concentrations and had a significant spatial-temporal trend. The highest concentrations were found during spring 2014 at site 1, in association with the intense rains that occurred in that season. The fact that glyphosate and AMPA concentrations were higher than the rest of the studied compounds is closely related to the land use within the watershed, as glyphosate was the most applied herbicide during the fallow period of glyphosate-resistant crops (soybean, maize). The pesticide mixture had a significant spatial-temporal trend, reaching the highest levels during storm flow events in spring 2014. The intensive rains in spring 2014 could be the main factor influencing stream hydrology and pesticide behavior at El Crespo watershed. The estimated annual pesticide losses were 3.11 g/ha at site 1 and 0.72 g/ha at site 2. This result indicates that an attenuation process could be decreasing pesticide loads during downstream transport from site 1 to site 2. Environ Toxicol Chem 2017;36:3206-3216. © 2017 SETAC. © 2017 SETAC.

  20. Spatially differentiated trends in urbanization, agricultural land abandonment and reclamation, and woodland recovery in Northern China

    Science.gov (United States)

    Wang, Chao; Gao, Qiong; Wang, Xian; Yu, Mei

    2016-11-01

    Uncovering magnitude, trend, and spatial pattern of land cover/land use changes (LCLUC) is crucial for understanding mechanisms of LCLUC and assisting land use planning and conservation. China has been undergoing unprecedented economic growth, massive rural-to-urban migration, and large-scale policy-driven ecological restoration, and therefore encountering enormous LCLUC in recent decades. However, comprehensive understandings of spatiotemporal LCLUC dynamics and underlying mechanisms are still lacking. Based on classification of annual LCLU maps from MODIS satellite imagery, we proposed a land change detection method to capture significant land change hotspots over Northern China during 2001-2013, and further analyzed temporal trends and spatial patterns of LCLUC. We found rapid decline of agricultural land near urban was predominantly caused by urban expansion. The process was especially strong in North China Plain with 14,057 km2 of urban gain and -21,017 km2 of agricultural land loss. To offset the loss of agricultural land, Northeast China Plain and Xinjiang were reclaimed. Substantial recovery of forests (49,908 km2) and closed shrubland (60,854 km2) occurred in mountainous regions due to abandoned infertile farmland, secondary succession, and governmental conservation policies. The spatial patterns and trends of LCLUC in Northern China provide information to support effective environmental policies towards sustainable development.

  1. Investigation of spatial trends and neurochemical impacts of mercury in herring gulls across the Laurentian Great Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Rutkiewicz, Jennifer [Department of Environmental Health Sciences, University of Michigan School of Public Health, 109 S. Observatory St, Ann Arbor, MI 48109 (United States); Scheuhammer, Anton; Crump, Doug; Jagla, Magdalena [Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3 (Canada); Basu, Niladri, E-mail: niladri@umich.ed [Department of Environmental Health Sciences, University of Michigan School of Public Health, 109 S. Observatory St, Ann Arbor, MI 48109 (United States)

    2010-08-15

    Herring gulls (Larus argentatus) bioaccumulate mercury (Hg) but it is unknown whether they are exposed at levels of neurological concern. Here we studied brain tissues from gulls at five Great Lakes colonies and one non-Great Lakes colony during spring of 2001 and 2003. Total brain Hg concentrations ranged from 0.14 to 2.0 {mu}g/g (dry weight) with a mean of 0.54 {mu}g/g. Gulls from Scotch Bonnet Island, on the easternmost edge of the Great Lakes, had significantly higher brain Hg than other colonies. No association was found between brain Hg concentration and [3H]-ligand binding to neurochemical receptors (N-methyl-D-aspartate, muscarinic cholinergic, nicotinic cholinergic) or nicotinic receptor {alpha}-7 relative mRNA expression as previously documented in other wildlife. In conclusion, spatial trends in Hg contamination exist in herring gulls across the Great Lakes basin, and herring gulls accumulate brain Hg but not at levels associated with sub-clinical neurochemical alterations. - Spatial trends in brain mercury exist in herring gulls across the Laurentian Great Lakes though levels are not associated with neurochemical biomarkers.

  2. Investigation of spatial trends and neurochemical impacts of mercury in herring gulls across the Laurentian Great Lakes

    International Nuclear Information System (INIS)

    Rutkiewicz, Jennifer; Scheuhammer, Anton; Crump, Doug; Jagla, Magdalena; Basu, Niladri

    2010-01-01

    Herring gulls (Larus argentatus) bioaccumulate mercury (Hg) but it is unknown whether they are exposed at levels of neurological concern. Here we studied brain tissues from gulls at five Great Lakes colonies and one non-Great Lakes colony during spring of 2001 and 2003. Total brain Hg concentrations ranged from 0.14 to 2.0 μg/g (dry weight) with a mean of 0.54 μg/g. Gulls from Scotch Bonnet Island, on the easternmost edge of the Great Lakes, had significantly higher brain Hg than other colonies. No association was found between brain Hg concentration and [3H]-ligand binding to neurochemical receptors (N-methyl-D-aspartate, muscarinic cholinergic, nicotinic cholinergic) or nicotinic receptor α-7 relative mRNA expression as previously documented in other wildlife. In conclusion, spatial trends in Hg contamination exist in herring gulls across the Great Lakes basin, and herring gulls accumulate brain Hg but not at levels associated with sub-clinical neurochemical alterations. - Spatial trends in brain mercury exist in herring gulls across the Laurentian Great Lakes though levels are not associated with neurochemical biomarkers.

  3. Spatial and temporal trends from an air quality sensor network near a heavily trafficked intersection

    Science.gov (United States)

    Orlando, P.; Vo, D.; Giossi, C.; George, L.

    2017-12-01

    With the world-wide increase in urbanization and the increasing usage of combustion vehicles in urban areas, traffic-related air pollution is a growing health hazard. However, there are limited studies that examine the spatial and temporal impacts of traffic-related pollutants within cities. In particular, there are few studies that look at traffic management and its potential for pollution mitigation. In a previous study we examined roadway pollution and traffic parameters with one roadway station instrumented with standard measurement instruments. With the advent of low-cost air pollution sensors, we have expanded our work by observing multiple sites within a neighborhood to understand spatial and temporal exposures. We have deployed a high-density sensor network around urban arterial corridors in SE Portland, Oregon. This network consisted of ten nodes measuring CO, NO, NO2 and O3, and ten nodes measuring CO, CO2, VOC and PM2.5. The co-location of standard measurement instruments provided insight towards the utility of our low-cost sensor network, as the different nodes varied in cost, and potentially in quality. We have identified near-real-time temporal trends and local-scale spatial patterns during the summer of 2017. Meteorological and traffic data were included to further characterize these patterns, exploring the potential for pollution mitigation.

  4. Modelling spatial patterns and temporal trends of wildfires in Galicia (NW Spain

    Directory of Open Access Journals (Sweden)

    Jesús Barreal

    2015-08-01

    Full Text Available Aim of study: The goal of this paper is to analyse the importance of the main contributing factors to the occurrence of wildfires. Area of study: We employ data from the region of Galicia during 2001-2010; although the similarities shared between this area and other rural areas may allow extrapolation of the present results. Material and Methods: The spatial dependence is analysed by using the Moran’s I and LISA statistics. We also conduct an econometric analysis modelling both, the number of fires and the relative size of afflicted woodland area as dependent variables, which depend on the climatic, land cover variables, and socio-economic characteristics of the affected areas. Fixed effects and random effect models are estimated in order to control for the heterogeneity between the Forest Districts in Galicia. Main results: Moran’s I and LISA statistics show that there is spatial dependence in the occurrence of Galician wildfires. Econometrics models show that climatology, socioeconomic variables, and temporal trends are also important to study both, the number of wildfires and the burned-forest ratio. Research highlights: We conclude that in addition to direct forest actions, other agricultural or social public plans, can help to reduce wildfires in rural areas or wildland-urban areas. Based on these conclusions, a number of guidelines are provided that may foster the development of better forest management policies in order to reduce the occurrence of wildfires.

  5. Spatial and temporal trends in runoff at long-term streamgages within and near the Chesapeake Bay Watershed

    Science.gov (United States)

    Rice, Karen C.; Hirsch, Robert M.

    2012-01-01

    Long-term streamflow data within the Chesapeake Bay watershed and surrounding area were analyzed in an attempt to identify trends in streamflow. Data from 30 streamgages near and within the Chesapeake Bay watershed were selected from 1930 through 2010 for analysis. Streamflow data were converted to runoff and trend slopes in percent change per decade were calculated. Trend slopes for three runoff statistics (the 7-day minimum, the mean, and the 1-day maximum) were analyzed annually and seasonally. The slopes also were analyzed both spatially and temporally. The spatial results indicated that trend slopes in the northern half of the watershed were generally greater than those in the southern half. The temporal analysis was done by splitting the 80-year flow record into two subsets; records for 28 streamgages were analyzed for 1930 through 1969 and records for 30 streamgages were analyzed for 1970 through 2010. The mean of the data for all sites for each year were plotted so that the following datasets were analyzed: the 7-day minimum runoff for the north, the 7-day minimum runoff for the south, the mean runoff for the north, the mean runoff for the south, the 1-day maximum runoff for the north, and the 1-day maximum runoff for the south. Results indicated that the period 1930 through 1969 was statistically different from the period 1970 through 2010. For the 7-day minimum runoff and the mean runoff, the latter period had significantly higher streamflow than did the earlier period, although within those two periods no significant linear trends were identified. For the 1-day maximum runoff, no step trend or linear trend could be shown to be statistically significant for the north, although the south showed a mixture of an upward step trend accompanied by linear downtrends within the periods. In no case was a change identified that indicated an increasing rate of change over time, and no general pattern was identified of hydrologic conditions becoming "more extreme

  6. Spatial trends in leaf size of Amazonian rainforest trees

    Science.gov (United States)

    Malhado, A. C. M.; Malhi, Y.; Whittaker, R. J.; Ladle, R. J.; Ter Steege, H.; Phillips, O. L.; Butt, N.; Aragão, L. E. O. C.; Quesada, C. A.; Araujo-Murakami, A.; Arroyo, L.; Peacock, J.; Lopez-Gonzalez, G.; Baker, T. R.; Anderson, L. O.; Almeida, S.; Higuchi, N.; Killeen, T. J.; Monteagudo, A.; Neill, D.; Pitman, N.; Prieto, A.; Salomão, R. P.; Vásquez-Martínez, R.; Laurance, W. F.

    2009-08-01

    Leaf size influences many aspects of tree function such as rates of transpiration and photosynthesis and, consequently, often varies in a predictable way in response to environmental gradients. The recent development of pan-Amazonian databases based on permanent botanical plots has now made it possible to assess trends in leaf size across environmental gradients in Amazonia. Previous plot-based studies have shown that the community structure of Amazonian trees breaks down into at least two major ecological gradients corresponding with variations in soil fertility (decreasing from southwest to northeast) and length of the dry season (increasing from northwest to south and east). Here we describe the geographic distribution of leaf size categories based on 121 plots distributed across eight South American countries. We find that the Amazon forest is predominantly populated by tree species and individuals in the mesophyll size class (20.25-182.25 cm2). The geographic distribution of species and individuals with large leaves (>20.25 cm2) is complex but is generally characterized by a higher proportion of such trees in the northwest of the region. Spatially corrected regressions reveal weak correlations between the proportion of large-leaved species and metrics of water availability. We also find a significant negative relationship between leaf size and wood density.

  7. Spatial patterns and temporal trends in mercury concentrations, precipitation depths, and mercury wet deposition in the North American Great Lakes region, 2002–2008

    International Nuclear Information System (INIS)

    Risch, Martin R.; Gay, David A.; Fowler, Kathleen K.; Keeler, Gerard J.; Backus, Sean M.; Blanchard, Pierrette; Barres, James A.; Dvonch, J. Timothy

    2012-01-01

    Annual and weekly mercury (Hg) concentrations, precipitation depths, and Hg wet deposition in the Great Lakes region were analyzed by using data from 5 monitoring networks in the USA and Canada for a 2002–2008 study period. High-resolution maps of calculated annual data, 7-year mean data, and net interannual change for the study period were prepared to assess spatial patterns. Areas with 7-year mean annual Hg concentrations higher than the 12 ng per liter water-quality criterion were mapped in 4 states. Temporal trends in measured weekly data were determined statistically. Monitoring sites with significant 7-year trends in weekly Hg wet deposition were spatially separated and were not sites with trends in weekly Hg concentration. During 2002–2008, Hg wet deposition was found to be unchanged in the Great Lakes region and its subregions. Any small decreases in Hg concentration apparently were offset by increases in precipitation. - Highlights: ► Data from 5 Hg and precipitation networks in the USA and Canada were combined for the first time. ► High-resolution maps and statistical trends tests were used for spatial and temporal data analysis. ► Some 7-year mean annual Hg concentrations exceeded a 12 ng per liter water-quality criterion. ► Small, localized decreases in Hg concentration were offset by increases in precipitation. ► Hg wet deposition was unchanged in the Great Lakes region and its subregions during 2002–2008. - Analysis of monitoring data from 5 networks in the USA and Canada determined that mercury wet deposition was unchanged in the North American Great Lakes region during 2002–2008.

  8. Spatial trends of co-planar contaminants in lobster digestive gland from the Gulf of St. Lawrence

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, W.L.; Arsenault, J.T.; Comeau, M. [Department of Fisheries and Oceans, Moncton, NB (Canada)

    1997-05-01

    A study on spatial trends of contaminants in Canadian marine biota was conducted between 1993 and 1995. Lobster digestive glands were sampled from eight locations on the Gulf of St. Lawrence near New Brunswick and Nova Scotia. A total of 15 gland samples were analysed for dioxin, furan and co-planar PCB congeners. The five highest concentrations measured (5.8-12 pg/g wet-weight) were from samples taken from within the barrier island of Miramichi Bay in New Brunswick. This is an area of municipal and industrial development where contamination levels in marine biota is a continuing local concern.

  9. Spatial analysis of cattle and shoat population in Ethiopia: growth trend, distribution and market access.

    Science.gov (United States)

    Leta, Samson; Mesele, Frehiwot

    2014-01-01

    The livestock subsector has an enormous contribution to Ethiopia's national economy and livelihoods of many Ethiopians. The subsector contributes about 16.5% of the national Gross Domestic Product (GDP) and 35.6% of the agricultural GDP. It also contributes 15% of export earnings and 30% of agricultural employment. The livestock subsector currently support and sustain livelihoods for 80% of all rural population. The GDP of livestock related activities valued at 59 billion birr. Ethiopian livestock population trends, distribution and marketing vary considerably across space and time due to a variety of reasons. This study was aimed to assess cattle and shoat population growth trend, distribution and their access to market. Regression analysis was used to assess the cattle and shoat population growth trend and Geographic Information Systems (GIS) techniques were used to determine the spatial distribution of cattle and shoats, and their relative access to market. The data sets used are agricultural census (2001/02) and annual CSA agricultural sample survey (1995/96 to 2012/13). In the past eighteen years, the livestock population namely cattle, sheep and goat grew from 54.5 million to over 103.5 million with average annual increment of 3.4 million. The current average national cattle, sheep and goat population per km(2) are estimated to be 71, 33 and 29 respectively (excluding Addis Ababa, Afar and Somali regions). From the total livestock population the country owns about 46% cattle, 43% sheep and 40% goats are reared within 10 km radius from major livestock market centres and all-weather roads. On the other hand, three fourth of the country's land mass which comprises 15% of the cattle, 20% of the sheep and 21% of goat population is not accessible to market (greater than 30 km from major livestock market centres). It is found that the central highland regions account for the largest share of livestock population and also more accessible to market. Defining the

  10. TREND MECHANISMS IN CONTEMPORARY FASHION

    DEFF Research Database (Denmark)

    Mackinney-Valentin, Maria

    2013-01-01

    Explores a spatial approach to trend mechanisms that is argued to be more contemporary than the traditional temporal appraoch.......Explores a spatial approach to trend mechanisms that is argued to be more contemporary than the traditional temporal appraoch....

  11. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  12. Explaining NDVI trends in northern Burkina Faso

    DEFF Research Database (Denmark)

    Rasmussen, Kjeld; Fensholt, Rasmus; Fog, Bjarne

    2014-01-01

    by a distinct spatial pattern and strongly dominated by negative trends in Normalized Difference Vegetation Index (NDVI). The aim of the paper is to explain this distinct pattern. When studied over the period 2000–2012, using NDVI data from the MODIS sensor the spatial pattern of NDVI trends indicates that non......-climatic factors are involved. By relating NDVI trends to landscape elements and land use change we demonstrate that NDVI trends in the north-western parts of the study area are mostly related to landscape elements, while this is not the case in the south-eastern parts, where rapidly changing land use, including....... expansion of irrigation, plays a major role. It is inferred that a process of increased redistribution of fine soil material, water and vegetation from plateaus and slopes to valleys, possibly related to higher grazing pressure, may provide an explanation of the observed pattern of NDVI trends. Further work...

  13. Mortality and Case Fatality Due to Visceral Leishmaniasis in Brazil: A Nationwide Analysis of Epidemiology, Trends and Spatial Patterns

    Science.gov (United States)

    Martins-Melo, Francisco Rogerlândio; Lima, Mauricélia da Silveira; Ramos, Alberto Novaes; Alencar, Carlos Henrique; Heukelbach, Jorg

    2014-01-01

    Background Visceral leishmaniasis (VL) is a significant public health problem in Brazil and several regions of the world. This study investigated the magnitude, temporal trends and spatial distribution of mortality related to VL in Brazil. Methods We performed a study based on secondary data obtained from the Brazilian Mortality Information System. We included all deaths in Brazil from 2000 to 2011, in which VL was recorded as cause of death. We present epidemiological characteristics, trend analysis of mortality and case fatality rates by joinpoint regression models, and spatial analysis using municipalities as geographical units of analysis. Results In the study period, 12,491,280 deaths were recorded in Brazil. VL was mentioned in 3,322 (0.03%) deaths. Average annual age-adjusted mortality rate was 0.15 deaths per 100,000 inhabitants and case fatality rate 8.1%. Highest mortality rates were observed in males (0.19 deaths/100,000 inhabitants), Brazil over the period, with different patterns between regions: increasing mortality rates in the North (Annual Percent Change – APC: 9.4%; 95% confidence interval – CI: 5.3 to 13.6), and Southeast (APC: 8.1%; 95% CI: 2.6 to 13.9); and increasing case fatality rates in the Northeast (APC: 4.0%; 95% CI: 0.8 to 7.4). Spatial analysis identified a major cluster of high mortality encompassing a wide geographic range in North and Northeast Brazil. Conclusions Despite ongoing control strategies, mortality related to VL in Brazil is increasing. Mortality and case fatality vary considerably between regions, and surveillance and control measures should be prioritized in high-risk clusters. Early diagnosis and treatment are fundamental strategies for reducing case fatality of VL in Brazil. PMID:24699517

  14. The long-term spatial-temporal trends and burden of esophageal cancer in one high-risk area: A population-registered study in Feicheng, China.

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    Xiubin Sun

    Full Text Available Feicheng County is a high-risk area for esophageal cancer in Shandong province, China. It is important to determine the long-term spatio-temporal trends in epidemiological characteristics and the burden of esophageal cancer, especially since the implementation of the national esophageal cancer screening program for early detection and treatment in 2005.The data collected in Feicheng County from 2001 to 2012 was extracted from the whole-population cancer registry system. The incidence, mortality, disability-adjusted life years (DALY and changing trends in esophageal cancer according to age and sex were calculated and described.The incidence rate of esophageal cancer in Feicheng was consistently high, and increased significantly for male, but not for female from 2001 to 2012, according to the joinpoint regression analysis. The highest and lowest yearly crude incidence rates were 160.78 and 95.97 per 100000 for males, and 81.36 and 52.17 per 100000 for females. The highest and lowest crude yearly mortality rates were 122.26 and 94.40 per 100000 for males, and 60.75 and 49.35 per 100000for females. Esophageal squamous cell carcinoma was the main pathology type and the tumor location changed significantly from 2001 to 2012. Overall, the DALY remained roughly stable and was estimated as 11.50 for males and 4.90 for females per 1000 people. The burden was mainly caused by premature death. There is an obvious spatial pattern in the distribution of incidence density and burden.Esophageal cancer remains a public health issue in Feicheng County with a high incidence, mortality and disease burden. The incidence and burden have obvious spatial heterogeneity, and further studies should be conducted to identify geographical risk factors for precise local prevention and control measures.

  15. Spatial and temporal trends of reference crop evapotranspiration and its influential variables in Yangtze River Delta, eastern China

    Science.gov (United States)

    Xu, Yu; Xu, Youpeng; Wang, Yuefeng; Wu, Lei; Li, Guang; Song, Song

    2017-11-01

    Reference crop evapotranspiration (ETo) is one of the most important links in hydrologic circulation and greatly affects regional agricultural production and water resource management. Its variation has drawn more and more attention in the context of global warming. We used the Penman-Monteith method of the Food and Agriculture Organization, based on meteorological factors such as air temperature, sunshine duration, wind speed, and relative humidity to calculate the ETo over 46 meteorological stations located in the Yangtze River Delta, eastern China, from 1957 to 2014. The spatial distributions and temporal trends in ETo were analyzed based on the modified Mann-Kendall trend test and linear regression method, while ArcGIS software was employed to produce the distribution maps. The multiple stepwise regression method was applied in the analysis of the meteorological variable time series to identify the causes of any observed trends in ETo. The results indicated that annual ETo showed an obvious spatial pattern of higher values in the north than in the south. Annual increasing trends were found at 34 meteorological stations (73.91 % of the total), which were mainly located in the southeast. Among them, 12 (26.09 % of the total) stations showed significant trends. We saw a dominance of increasing trends in the monthly ETo except for January, February, and August. The high value zone of monthly ETo appeared in the northwest from February to June, mid-south area from July to August, and southeast coastal area from September to January. The research period was divided into two stages—stage I (1957-1989) and stage II (1990-2014)—to investigate the long-term temporal ETo variation. In stage I, almost 85 % of the total stations experienced decreasing trends, while more than half of the meteorological stations showed significant increasing trends in annual ETo during stage II except in February and September. Relative humidity, wind speed, and sunshine duration were

  16. Global Trends of Tropospheric NO2 Observed From Space

    Science.gov (United States)

    Schneider, P.; van der A, R. J.

    2012-04-01

    Nitrogen Dioxide (NO2) is one of the major atmospheric pollutants and is primarily emitted by industrial activity and transport. While observations of NO2 are frequently being carried out at air quality stations, such measurements are not able to provide a global perspective of spatial patterns in NO2 concentrations and their associated trends due to the stations' limited spatial representativity and an extremely sparse and often completely non-existent station coverage in developing countries. Satellite observations of tropospheric NO2 are able to overcome this issue and provide an unprecedented global view of spatial patterns in NO2 levels and due to their homogeneity are well suited for studying trends. Here we present results of a global trend analysis from nearly a decade of NO2 observations made by the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY) instrument onboard the Envisat satellite platform. Using only SCIAMACHY data allows for mapping global and regional trends at an unprecedented spatial resolution since no aggregation to the coarser resolution of other sensors is necessary. Monthly average tropospheric NO2 column data was acquired for the period between August 2002 and August 2011. A trend analysis was subsequently performed by fitting a statistical model including a seasonal cycle and linear trend to the time series extracted at each grid cell. The linear trend component and the trend uncertainty were then mapped spatially at both regional and global scales. The results show that spatially contiguous areas of significantly increasing NO2 levels are found primarily in Eastern China, with absolute trends of up to 4.05 (± 0.41) - 1015 molecules cm-2 yr-1 at the gridcell level and large areas showing rapid relative increases of 10-20 percent per year. In addition, many urban agglomerations in Asia and the Middle East similarly exhibit significantly increasing trends, with Dhaka in Bangladesh being the megacity with

  17. Trends and Spatial Distribution Characteristics of Sustainability in Eastern Anhui Province, China

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    Jian Zhang

    2014-11-01

    Full Text Available This study analyzes and evaluates the status and long-term trend of regional economic sustainability in eastern Anhui Province, China. Based on the triangle model and the definition of economic sustainable development, this study evaluates the interrelationship among regional economic development, resource-energy consumption, environmental pollution, and ecological performance. The sustainable and comprehensive utilization situation in the study region from 1975–2012 is examined. The results show that in 2012, the comprehensive development in the study region had a general status in terms of sustainability. The sustainable development trend of the seven administrative subunits inside the region had a weak and general status in terms of sustainability, while the status of sustainability in the southeastern part of the region was better than that in the northwest. During the period from 1975–1998, the study region’s comprehensive development presented a trend of general sustainability. In the period from 1998–2012, the region experienced a trend of very strong sustainability in its development. These statuses and trends have a certain relationship with the study region’s strong economic development and environmental protection over the past 37 years. The triangle method, as an intuitive platform for illustrating sustainability status and trends in economic development, seems to hold promise as an analytical management tool given its simplicity, ease of use, and flexibility.

  18. Spatial and temporal trends in alcohol consumption in Belgian cities: A wastewater-based approach.

    Science.gov (United States)

    Boogaerts, Tim; Covaci, Adrian; Kinyua, Juliet; Neels, Hugo; van Nuijs, Alexander L N

    2016-03-01

    In recent years, scientific evidence has emerged that wastewater-based epidemiology can deliver complementary information concerning the use of different substances of abuse. In this study, the potential of wastewater-based epidemiology in monitoring spatial and temporal trends in alcohol consumption in different populations in Belgium has been examined. Concentrations of ethyl sulphate, a minor Phase-II metabolite of ethanol, in 163 influent wastewater samples from eight wastewater treatment plants in Belgium in the period 2013-2015 were measured with liquid chromatography coupled to tandem mass spectrometry and used to estimate alcohol consumption. The highest levels of alcohol consumption were detected in the metropoles Antwerp and Brussels compared to smaller villages. Annual variations were detected, with a higher alcohol consumption measured in 2013 compared with 2014. The weekly pattern showed a clear week and weekend difference in alcohol use, with intermediate levels on Monday and Friday. The results were extrapolated and a use of 5.6L pure alcohol per year per inhabitant aged 15+ has been estimated in Belgium. The comparison with available information on drinking habits of the Belgian population further demonstrated the usefulness of the wastewater-based epidemiology approach. This is the largest wastewater-based epidemiology study monitoring alcohol consumption to date, demonstrating that objective and quick information on spatio-temporal trends in alcohol consumption on a local and (inter)national scale can be obtained. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Spatial-temporal trend for mother-to-child transmission of HIV up to infancy and during pre-Option B+ in western Kenya, 2007-13.

    Science.gov (United States)

    Waruru, Anthony; Achia, Thomas N O; Muttai, Hellen; Ng'ang'a, Lucy; Zielinski-Gutierrez, Emily; Ochanda, Boniface; Katana, Abraham; Young, Peter W; Tobias, James L; Juma, Peter; De Cock, Kevin M; Tylleskär, Thorkild

    2018-01-01

    Using spatial-temporal analyses to understand coverage and trends in elimination of mother-to-child transmission of HIV (e-MTCT) efforts may be helpful in ensuring timely services are delivered to the right place. We present spatial-temporal analysis of seven years of HIV early infant diagnosis (EID) data collected from 12 districts in western Kenya from January 2007 to November 2013, during pre-Option B+ use. We included in the analysis infants up to one year old. We performed trend analysis using extended Cochran-Mantel-Haenszel stratified test and logistic regression models to examine trends and associations of infant HIV status at first diagnosis with: early diagnosis (ever having breastfed, use of single dose nevirapine, and maternal antiretroviral therapy status. We examined these covariates and fitted spatial and spatial-temporal semiparametric Poisson regression models to explain HIV-infection rates using R-integrated nested Laplace approximation package. We calculated new infections per 100,000 live births and used Quantum GIS to map fitted MTCT estimates for each district in Nyanza region. Median age was two months, interquartile range 1.5-5.8 months. Unadjusted pooled positive rate was 11.8% in the seven-years period and declined from 19.7% in 2007 to 7.0% in 2013, p best in explaining geographical variation in MTCT. Improved EID uptake and reduced MTCT rates are indicators of progress towards e-MTCT. Cojoined analysis of time and covariates in a spatial context provides a robust approach for explaining differences in programmatic impact over time. During this pre-Option B+ period, the prevention of mother to child transmission program in this region has not achieved e-MTCT target of ≤50 infections per 100,000 live births. Geographical disparities in program achievements may signify gaps in spatial distribution of e-MTCT efforts and could indicate areas needing further resources and interventions.

  20. Spatio-temporal trends of rainfall across Indian river basins

    Science.gov (United States)

    Bisht, Deepak Singh; Chatterjee, Chandranath; Raghuwanshi, Narendra Singh; Sridhar, Venkataramana

    2018-04-01

    Daily gridded high-resolution rainfall data of India Meteorological Department at 0.25° spatial resolution (1901-2015) was analyzed to detect the trend in seasonal, annual, and maximum cumulative rainfall for 1, 2, 3, and 5 days. The present study was carried out for 85 river basins of India during 1901-2015 and pre- and post-urbanization era, i.e., 1901-1970 and 1971-2015, respectively. Mann-Kendall ( α = 0.05) and Theil-Sen's tests were employed for detecting the trend and percentage of change over the period of time, respectively. Daily extreme rainfall events, above 95 and 99 percentile threshold, were also analyzed to detect any trend in their magnitude and number of occurrences. The upward trend was found for the majority of the sub-basins for 1-, 2-, 3-, and 5-day maximum cumulative rainfall during the post-urbanization era. The magnitude of extreme threshold events is also found to be increasing in the majority of the river basins during the post-urbanization era. A 30-year moving window analysis further revealed a widespread upward trend in a number of extreme threshold rainfall events possibly due to urbanization and climatic factors. Overall trends studied against intra-basin trend across Ganga basin reveal the mixed pattern of trends due to inherent spatial heterogeneity of rainfall, therefore, highlighting the importance of scale for such studies.

  1. Spatial and Temporal Trends in the Location of the Lifetime Maximum Intensity of Tropical Cyclones

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    Sarah A. Tennille

    2017-10-01

    Full Text Available The climatology of tropical cyclones is an immediate research need, specifically to better understand their long-term patterns and elucidate their future in a changing climate. One important pattern that has recently been detected is the poleward shift of the lifetime maximum intensity (LMI of tropical cyclones. This study further assessed the recent (1977–2015 spatial changes in the LMI of tropical cyclones, specifically those of tropical storm strength or stronger in the North Atlantic and northern West Pacific basins. Analyses of moving decadal means suggested that LMI locations migrated south in the North Atlantic and north in the West Pacific. In addition to a linear trend, there is a cyclical migration of LMI that is especially apparent in the West Pacific. Relationships between LMI migration and intensity were explored, as well as LMI location relative to landfall. The southerly trend of LMI in the North Atlantic was most prevalent in the strongest storms, resulting in these storms reaching their LMI farther from land. The relationship between intensity and LMI migration in the West Pacific was not as clear, but the most intense storms have been reaching LMI closer to their eventual landfall location. This work adds to those emphasizing the importance of understanding the climatology of the most intense hurricanes and shows there are potential human impacts resulting from any migration of LMI.

  2. Spatial-temporal Evolution of Karst Rocky Desertification and Future Trends Based on CA-Markov Methods in Typical Karst Valley

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    CHEN Fei

    2018-02-01

    Full Text Available Karst rocky desertification(KRDhas become the most serious ecological disaster in Southwest China. It is very important and much-needed to explore the rule of spatial-temporal evolution of KRD for ecological restoration and sustainable development of the region. In this paper, the improved accurate remote sensing image interpreting method and CA-Markov prediction method were used to explore the spatial-temporal evolution rule of KRD in the study area from 1990 to 2021 based on the long time line remote sensing image of the year of 1990, 2004 and 2016. The results were as follows:the spatial -temporal evolution rule of KRD presented "first deterioration and then improvement" in the study area at nearly 30 years. The deterioration of KRD was affected by high intensity overload human activities and natural disasters in 1990-2004, which made the ecological environment deterioration. However, the KRD had gradually improved with the implementation of a series of governance projects, and a large number of rural labor forces were liberated from the land in 2004-2016, which made the natural environment restoration, and ecological system was getting better and better. At the same time, the trend of KRD evolution was showing improvement from the predicted years of 2016-2021 and the ecological environment in the region continued to become better.

  3. Googling trends in conservation biology.

    Science.gov (United States)

    Proulx, Raphaël; Massicotte, Philippe; Pépino, Marc

    2014-02-01

    Web-crawling approaches, that is, automated programs data mining the internet to obtain information about a particular process, have recently been proposed for monitoring early signs of ecosystem degradation or for establishing crop calendars. However, lack of a clear conceptual and methodological framework has prevented the development of such approaches within the field of conservation biology. Our objective was to illustrate how Google Trends, a freely accessible web-crawling engine, can be used to track changes in timing of biological processes, spatial distribution of invasive species, and level of public awareness about key conservation issues. Google Trends returns the number of internet searches that were made for a keyword in a given region of the world over a defined period. Using data retrieved online for 13 countries, we exemplify how Google Trends can be used to study the timing of biological processes, such as the seasonal recurrence of pollen release or mosquito outbreaks across a latitudinal gradient. We mapped the spatial extent of results from Google Trends for 5 invasive species in the United States and found geographic patterns in invasions that are consistent with their coarse-grained distribution at state levels. From 2004 through 2012, Google Trends showed that the level of public interest and awareness about conservation issues related to ecosystem services, biodiversity, and climate change increased, decreased, and followed both trends, respectively. Finally, to further the development of research approaches at the interface of conservation biology, collective knowledge, and environmental management, we developed an algorithm that allows the rapid retrieval of Google Trends data. © 2013 Society for Conservation Biology.

  4. Combined multivariate statistical techniques, Water Pollution Index (WPI) and Daniel Trend Test methods to evaluate temporal and spatial variations and trends of water quality at Shanchong River in the Northwest Basin of Lake Fuxian, China.

    Science.gov (United States)

    Wang, Quan; Wu, Xianhua; Zhao, Bin; Qin, Jie; Peng, Tingchun

    2015-01-01

    Understanding spatial and temporal variations in river water quality and quantitatively evaluating the trend of changes are important in order to study and efficiently manage water resources. In this study, an analysis of Water Pollution Index (WPI), Daniel Trend Test, Cluster Analysis and Discriminant Analysis are applied as an integrated approach to quantitatively explore the spatial and temporal variations and the latent sources of water pollution in the Shanchong River basin, Northwest Basin of Lake Fuxian, China. We group all field surveys into 2 clusters (dry season and rainy season). Moreover, 14 sampling sites have been grouped into 3 clusters for the rainy season (highly polluted, moderately polluted and less polluted sites) and 2 clusters for the dry season (highly polluted and less polluted sites) based on their similarities and the level of pollution during the two seasons. The results show that the main trend of pollution was aggravated during the transition from the dry to the rainy season. The Water Pollution Index of Total Nitrogen is the highest of all pollution parameters, whereas the Chemical Oxygen Demand (Chromium) is the lowest. Our results also show that the main sources of pollution are farming activities alongside the Shanchong River, soil erosion and fish culture at Shanchong River reservoir area and domestic sewage from scattered rural residential area. Our results suggest that strategies to prevent water pollutionat the Shanchong River basin need to focus on non-point pollution control by employing appropriate fertilizer formulas in farming, and take the measures of soil and water conservation at Shanchong reservoir area, and purifying sewage from scattered villages.

  5. Combined multivariate statistical techniques, Water Pollution Index (WPI and Daniel Trend Test methods to evaluate temporal and spatial variations and trends of water quality at Shanchong River in the Northwest Basin of Lake Fuxian, China.

    Directory of Open Access Journals (Sweden)

    Quan Wang

    Full Text Available Understanding spatial and temporal variations in river water quality and quantitatively evaluating the trend of changes are important in order to study and efficiently manage water resources. In this study, an analysis of Water Pollution Index (WPI, Daniel Trend Test, Cluster Analysis and Discriminant Analysis are applied as an integrated approach to quantitatively explore the spatial and temporal variations and the latent sources of water pollution in the Shanchong River basin, Northwest Basin of Lake Fuxian, China. We group all field surveys into 2 clusters (dry season and rainy season. Moreover, 14 sampling sites have been grouped into 3 clusters for the rainy season (highly polluted, moderately polluted and less polluted sites and 2 clusters for the dry season (highly polluted and less polluted sites based on their similarities and the level of pollution during the two seasons. The results show that the main trend of pollution was aggravated during the transition from the dry to the rainy season. The Water Pollution Index of Total Nitrogen is the highest of all pollution parameters, whereas the Chemical Oxygen Demand (Chromium is the lowest. Our results also show that the main sources of pollution are farming activities alongside the Shanchong River, soil erosion and fish culture at Shanchong River reservoir area and domestic sewage from scattered rural residential area. Our results suggest that strategies to prevent water pollutionat the Shanchong River basin need to focus on non-point pollution control by employing appropriate fertilizer formulas in farming, and take the measures of soil and water conservation at Shanchong reservoir area, and purifying sewage from scattered villages.

  6. Analyzing spatial and temporal trends in Aboveground Biomass within the Acadian New England Forests using the complete Landsat Archive

    Science.gov (United States)

    Kilbride, J. B.; Fraver, S.; Ayrey, E.; Weiskittel, A.; Braaten, J.; Hughes, J. M.; Hayes, D. J.

    2017-12-01

    Forests within the New England states and Canadian Maritime provinces, here described as the Acadian New England (ANE) forests, have undergone substantial disturbances due to insect, fire, and anthropogenic factors. Through repeated satellite observations captures by USGS's Landsat program, 45 years of disturbance information can be incorporated into modeling efforts to better understand the spatial and temporal trends in forest above ground biomass (AGB). Using Google's Earth Engine, annual mosaics were developed for the ANE study area and then disturbance and recovery metrics were developed using the temporal segmentation algorithm VeRDET. Normalization procedures were developed to incorporate the Landsat Multispectral Scanner (MSS, 1972 - 1985) data alongside the modern era of Landsat Thematic Mapper (TM, 1984-2013), Enhanced Thematic Mapper plus (ETM+, 1999 - present), and Operational Land Imager (OLI, 2013- present) data products. This has enabled the creation of a dataset with an unprecedented spatial and temporal view of forest landscape change. Model training was performed using was the Forest Inventory Analysis (FIA) and New Brunswick Permanent Sample Plot data datasets. Modeling was performed using parametric techniques such as mixed effects models and non-parametric techniques such as k-NN imputation and generalized boosted regression. We compare the biomass estimate and model accuracy to other inventory and modeling studies produced within this study area. The spatial and temporal patterns of stock changes are analyzed against resource policy, land ownership changes, and forest management.

  7. A spatial econometric analysis of land-use change with land cover trends data: an application to the Pacific Northwest

    Science.gov (United States)

    David J. Lewis; Ralph J. Alig

    2014-01-01

    This paper develops a plot-level spatial econometric land-use model and estimates it with U.S. Geological Survey Land Cover Trends (LCT) geographic information system panel data for the western halves of the states of Oregon and Washington. The discrete-choice framework we use models plot-scale choices of the three dominant land uses in this region: forest, agriculture...

  8. Spatial distributions and temporal trends in polybrominated diphenyl ethers in Detroit River suspended sediments.

    Science.gov (United States)

    Marvin, Chris; Waltho, Jasmine; Jia, Julia; Burniston, Debbie

    2013-05-01

    Suspended sediments from the Detroit River were collected using sediment traps at sites ranging from western Lake Erie to southern Lake St. Clair to assess spatial distributions and temporal trends of polybrominated diphenyl ethers (PBDEs). The distribution of PBDEs in suspended sediments in the Detroit River appeared influenced by shoreline-based contemporary urban and industrial activities, which stood in contrast to PCBs that were associated with areas of historic industrial activity. Temporal trend data indicate that total PBDE concentrations decreased in the period after 2000 in response to cessation of production of the penta- and octa BDE formulations. Concentrations of total PBDEs ranged from roughly 7 ng g(-1) (4 ng g(-1) BDE 209) in southern Lake St. Clair to several hundred ng g(-1) (60-180 ng g(-1) BDE 209) in the lower reaches of the Detroit River. The widespread occurrence of PBDEs in Detroit River suspended sediments suggests that large urban areas can act as diffuse sources of these chemicals that are used in modern industrial applications and consumer products. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  9. Spatial and Temporal Variability and Trends in 2001-2016 Global Fire Activity

    Science.gov (United States)

    Earl, Nick; Simmonds, Ian

    2018-03-01

    Fire regimes across the globe have great spatial and temporal variability, and these are influence by many factors including anthropogenic management, climate, and vegetation types. Here we utilize the satellite-based "active fire" product, from Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, to statistically analyze variability and trends in fire activity from the global to regional scales. We split up the regions by economic development, region/geographical land use, clusters of fire-abundant areas, or by religious/cultural influence. Weekly cycle tests are conducted to highlight and quantify part of the anthropogenic influence on fire regime across the world. We find that there is a strong statistically significant decline in 2001-2016 active fires globally linked to an increase in net primary productivity observed in northern Africa, along with global agricultural expansion and intensification, which generally reduces fire activity. There are high levels of variability, however. The large-scale regions exhibit either little change or decreasing in fire activity except for strong increasing trends in India and China, where rapid population increase is occurring, leading to agricultural intensification and increased crop residue burning. Variability in Canada has been linked to a warming global climate leading to a longer growing season and higher fuel loads. Areas with a strong weekly cycle give a good indication of where fire management is being applied most extensively, for example, the United States, where few areas retain a natural fire regime.

  10. AIDS in adults 50 years of age and over: characteristics, trends and spatial distribution of the risk1

    Science.gov (United States)

    Nogueira, Jordana de Almeida; Silva, Antônia Oliveira; de Sá, Laísa Ribeiro; de Almeida, Sandra Aparecida; Monroe, Aline Aparecida; Villa, Tereza Cristina Scatena

    2014-01-01

    Objective to analyze the sociodemographic characteristics, epidemic trend and spatial distribution of the risk of AIDS in adults 50 years of age and over. Method population-based, ecological study, that used secondary data from the Notifiable Disease Information System (Sinan/AIDS) of Paraíba state from the period January 2000 to December 2010. Results during the study period, 307 cases of AIDS were reported among people 50 years of age or over. There was a predominance of males (205/66, 8%), mixed race, and low education levels. The municipalities with populations above 100 thousand inhabitants reported 58.5% of the cases. There was a progressive increase in cases among women; an increasing trend in the incidence (positive linear correlation); and an advance in the geographical spread of the disease, with expansion to the coastal region and to the interior of the state, reaching municipalities with populations below 30 thousand inhabitants. In some locations the risk of disease was 100 times greater than the relative risk for the state. Conclusion aging, with the feminization and interiorization of the epidemic in adults 50 years of age and over, confirms the need for the induction of affirmative policies targeted toward this age group. PMID:25029044

  11. Stratospheric Temperature Trends Observed by TIMED/SABER

    Science.gov (United States)

    Xian, T.; Tan, R.

    2017-12-01

    Trends in the stratospheric temperature are studied based on the temperature profile observation from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). The spatially trends are evaluated in different time scales ranging from decadal to monthly resolved. The results indicate a signature of BDC acceleration. There are strong warming trends (up to 9 K/decade) in the middle to upper stratosphere in the high latitude spring, summer, and autumn seasons, accompanied by strong cooling trends in the lower stratosphere. Besides, strong warming trends occurs through the whole stratosphere over the Southern Hemisphere, which confirms Antarctic ozone layer healing since 2000. In addition, the results demonstrate a significant warming trends in the middle of tropical stratosphere, which becomes strongest during June-July-August.

  12. Spatial and temporal trends of contaminants in eggs of wading birds from San Francisco Bay, California

    Science.gov (United States)

    Hothem, R.L.; Roster, D.L.; King, K.A.; Keldsen, T.J.; Marois, Katherine C.; Wainwright, S.E.

    1995-01-01

    Between 1989 and 1991, reproduction by black-crowned night-herons (Nycticorax nycticorax) and snowy egrets (Egretta thula) was studied at sites in San Francisco Bay. Eggs were collected from these and other bay sites and from South Wilbur Flood Area, a reference site in California's San Joaquin Valley. Eggs were analyzed for inorganic trace elements, organochlorine pesticides, and polychlorinated biphenyls (PCBs). Results were compared among sites and years and with results of previous studies. There was some evidence of impaired reproduction, but concentrations of contaminants were generally lower than threshold levels for such effects. Egg hatchability was generally good, with predation being the factor that most limited reproductive success. Mean PCB concentrations were generally higher in eggs from the south end of San Francisco Bay than from the north, but the only temporal change, an increase, was observed at Alcatraz Island. There were spatial differences for p,p'-DDE in night-heron eggs in 1990, but the highest mean concentration of DDE was in night-heron eggs from South Wilbur in 1991. Temporal declines in maximum concentrations of DDE in eggs were observed in the bay, but means did not change significantly over time, At Bair Island in the southern end of the bay, mean concentrations of mercury decreased while selenium increased in night-heron eggs over time, but there were no clear bay-wide spatial or temporal trends for either element.

  13. Isotopic source signatures: Impact of regional variability on the δ13CH4 trend and spatial distribution

    Science.gov (United States)

    Feinberg, Aryeh I.; Coulon, Ancelin; Stenke, Andrea; Schwietzke, Stefan; Peter, Thomas

    2018-02-01

    The atmospheric methane growth rate has fluctuated over the past three decades, signifying variations in methane sources and sinks. Methane isotopic ratios (δ13CH4) differ between emission categories, and can therefore be used to distinguish which methane sources have changed. However, isotopic modelling studies have mainly focused on uncertainties in methane emissions rather than uncertainties in isotopic source signatures. We simulated atmospheric δ13CH4 for the period 1990-2010 using the global chemistry-climate model SOCOL. Empirically-derived regional variability in the isotopic signatures was introduced in a suite of sensitivity simulations. These simulations were compared to a baseline simulation with commonly used global mean isotopic signatures. We investigated coal, natural gas/oil, wetland, livestock, and biomass burning source signatures to determine whether regional variations impact the observed isotopic trend and spatial distribution. Based on recently published source signature datasets, our calculated global mean isotopic signatures are in general lighter than the commonly used values. Trends in several isotopic signatures were also apparent during the period 1990-2010. Tropical livestock emissions grew during the 2000s, introducing isotopically heavier livestock emissions since tropical livestock consume more C4 vegetation than midlatitude livestock. Chinese coal emissions, which are isotopically heavy compared to other coals, increase during the 2000s leading to higher global values of δ13CH4 for coal emissions. EDGAR v4.2 emissions disagree with the observed atmospheric isotopic trend for almost all simulations, confirming past doubts about this emissions inventory. The agreement between the modelled and observed δ13CH4 interhemispheric differences improves when regional source signatures are used. Even though the simulated results are highly dependent on the choice of methane emission inventories, they emphasize that the commonly used

  14. [Ecological risk assessment of land use based on exploratory spatial data analysis (ESDA): a case study of Haitan Island, Fujian Province].

    Science.gov (United States)

    Wu, Jian; Chen, Peng; Wen, Chao-Xiang; Fu, Shi-Feng; Chen, Qing-Hui

    2014-07-01

    As a novel environment management tool, ecological risk assessment has provided a new perspective for the quantitative evaluation of ecological effects of land-use change. In this study, Haitan Island in Fujian Province was taken as a case. Based on the Landsat TM obtained in 1990, SPOT5 RS images obtained in 2010, general layout planning map of Pingtan Comprehensive Experimental Zone in 2030, as well as the field investigation data, we established an ecological risk index to measure ecological endpoints. By using spatial autocorrelation and semivariance analysis of Exploratory Spatial Data Analysis (ESDA), the ecological risk of Haitan Island under different land-use situations was assessed, including the past (1990), present (2010) and future (2030), and the potential risk and its changing trend were analyzed. The results revealed that the ecological risk index showed obvious scale effect, with strong positive correlation within 3000 meters. High-high (HH) and low-low (LL) aggregations were predominant types in spatial distribution of ecological risk index. The ecological risk index showed significant isotropic characteristics, and its spatial distribution was consistent with Anselin Local Moran I (LISA) distribution during the same period. Dramatic spatial distribution change of each ecological risk area was found among 1990, 2010 and 2030, and the fluctuation trend and amplitude of different ecological risk areas were diverse. The low ecological risk area showed a rise-to-fall trend while the medium and high ecological risk areas showed a fall-to-rise trend. In the planning period, due to intensive anthropogenic disturbance, the high ecological risk area spread throughout the whole region. To reduce the ecological risk in land-use and maintain the regional ecological security, the following ecological risk control strategies could be adopted, i.e., optimizing the spatial pattern of land resources, protecting the key ecoregions and controlling the scale of

  15. Modeling Alaska boreal forests with a controlled trend surface approach

    Science.gov (United States)

    Mo Zhou; Jingjing Liang

    2012-01-01

    An approach of Controlled Trend Surface was proposed to simultaneously take into consideration large-scale spatial trends and nonspatial effects. A geospatial model of the Alaska boreal forest was developed from 446 permanent sample plots, which addressed large-scale spatial trends in recruitment, diameter growth, and mortality. The model was tested on two sets of...

  16. Spatial-temporal Evolution of Vegetation Coverage and Analysis of it’s Future Trends in Wujiang River Basin

    Science.gov (United States)

    Xiao, Jianyong; Bai, Xiaoyong; Zhou, Dequan; Qian, Qinghuan; Zeng, Cheng; Chen, Fei

    2018-01-01

    Vegetation coverage dynamics is affected by climatic, topography and human activities, which is an important indicator reflecting the regional ecological environment. Revealing the spatial-temporal characteristics of vegetation coverage is of great significance to the protection and management of ecological environment. Based on MODIS NDVI data and the Maximum Value Composites (MVC), we excluded soil spectrum interference to calculate Fractional Vegetation Coverage (FVC). Then the long-term FVC was used to calculate the spatial pattern and temporal variation of vegetation in Wujiang River Basin from 2000 to 2016 by using Trend analysis and Hurst index. The relationship between topography and spatial distribution of FVC was analyzed. The main conclusions are as follows: (1) The multi-annual mean vegetation coverage reveals a spatial distribution variation characteristic of low value in midstream and high level in other parts of the basin, owing a mean value of 0.6567. (2) From 2000 to 2016, the FVC of the Wujiang River Basin fluctuated between 0.6110 and 0.7380, and the overall growth rate of FVC was 0.0074/a. (3) The area of vegetation coverage tending to improve is more than that going to degrade in the future. Grass land, Arable land and Others improved significantly; karst rocky desertification comprehensive management project lead to persistent vegetation coverage improvement of Grass land, Arable land and Others. Residential land is covered with obviously degraded vegetation, resulting of urban sprawl; (4) The spatial distribution of FVC is positively correlated with TNI. Researches of spatial-temporal evolution of vegetation coverage have significant meaning for the ecological environment protection and management of the Wujiang River Basin.

  17. Temporal trends and spatial variation characteristics of primary air pollutants emissions from coal-fired industrial boilers in Beijing, China

    International Nuclear Information System (INIS)

    Xue, Yifeng; Tian, Hezhong; Yan, Jing; Zhou, Zhen; Wang, Junling; Nie, Lei; Pan, Tao; Zhou, Junrui; Hua, Shenbing; Wang, Yong; Wu, Xiaoqing

    2016-01-01

    Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007–2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM 10 , PM 2.5 , SO 2 , NO x , CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NO x and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. - Highlights: • A unit-based emission inventory of coal-fired industrial boilers is developed. • Temporal trend of historical period 2007–2013 and the future till 2030 is

  18. Zika pandemic online trends, incidence and health risk communication: a time trend study.

    Science.gov (United States)

    Adebayo, Gbenga; Neumark, Yehuda; Gesser-Edelsburg, Anat; Abu Ahmad, Wiessam; Levine, Hagai

    2017-01-01

    We aimed to describe the online search trends of Zika and examine their association with Zika incidence, assess the content of Zika-related press releases issued by leading health authorities and examine the association between online trends and press release timing. Using Google Trends, the 1 May 2015 to 30 May 2016 online trends of Zika and associated search terms were studied globally and in the five countries with the highest numbers of suspected cases. Correlations were then examined between online trends and Zika incidence in these countries. All Zika-related press releases issued by WHO/Pan America Health Organization (PAHO) and Centers for Disease Control and Prevention (CDC) during the study period were assessed for transparency, uncertainty and audience segmentation. Witte's Extended Parallel Process Model was applied to assess self-efficacy, response efficacy, susceptibility and severity. AutoRegressive Integrated Moving Average with an eXogenous predictor variable (ARIMAX) (p,d,q) regression modelling was used to quantify the association between online trends and the timing of press releases. Globally, Zika online search trends were low until the beginning of 2016, when interest rose steeply. Strong correlations (r=0.748-0.922; ponline trends and the number of suspected Zika cases in four of the five countries studied. Compared with press releases issued by WHO/PAHO, CDC press releases were significantly more likely to provide contact details and links to other resources, include figures/graphs, be risk-advisory in nature and be more readable and briefer. ARIMAX modelling results indicate that online trends preceded by 1 week press releases by WHO (stationary-R 2 =0.345; ponline trends can aid in pandemic surveillance. Identification of shortcomings in the content and timing of Zika press releases can help guide health communication efforts in the current pandemic and future public health emergencies.

  19. Spatial and temporal evaluation of long term trend (2005-2014) of OMI retrieved NO2 and SO2 concentrations in Henan Province, China

    Science.gov (United States)

    Zhang, Leishi; Lee, Chih Sheng; Zhang, Ruiqin; Chen, Liangfu

    2017-04-01

    Tropospheric NO2 and SO2 concentrations are of great importance with regard to air quality, atmospheric chemistry, and climate change. Due to lack of surface monitoring stations, this study analyzes long term trend of NO2 and SO2 levels (2005-2014), retrieved from Ozone Monitoring Instrument (OMI) board on the NASA's Aura satellite, in an important region of China - Henan Province. Henan Province, located in North China Plain, has encountered serious air pollution problems including extremely high PM2.5 concentrations and as one of the most polluted region in China. The satellite spatial images clearly show that high levels of both NO2 and SO2 are concentrated in north and northeastern regions with much lower levels observed in other parts of Henan. Both pollutants exhibit the highest levels in winter with the least in summer/spring. The temporal trend analysis based on moving average of deseasonalized and decyclic data indicates that for NO2, there is a continuous increasing pattern from 2005 to 2011 at 6.4% per year, thereafter, it shows a decreasing trend (10.6% per year). As for SO2, the increasing trend is about 16% per year from 2005 to 2007 with decreasing rate 7% per year from 2007 to 2014. The economic development with incredible annual 11% GDP growth in Henan is responsible for increasing levels of NO2 and SO2. The observed decreasing SO2 level starting in 2007 is due to reduced SO2 emission, utilization of flue gas desulfurization (FGD) devices and to some extent, in preparation of Beijing 2008 Olympic Games. On the other hand, increasing vehicle numbers (155% from 2006 to 2012) and coal consumption (37% during the same span), along with the lack of denitration process for removing flue/exhaust gas NOx are responsible for increasing NO2 trend until 2011. The ratio of SO2/NO2 started decreasing in 2007 and dropped significantly from 2011 to 2013 indicating good performance of FGD and ever increasing NOx contribution from mobile sources. Unlike those

  20. Drivers for spatial, temporal and long-term trends in atmospheric ammonia and ammonium in the UK

    Directory of Open Access Journals (Sweden)

    Y. S. Tang

    2018-01-01

    Full Text Available A unique long-term dataset from the UK National Ammonia Monitoring Network (NAMN is used here to assess spatial, seasonal and long-term variability in atmospheric ammonia (NH3: 1998–2014 and particulate ammonium (NH4+: 1999–2014 across the UK. Extensive spatial heterogeneity in NH3 concentrations is observed, with lowest annual mean concentrations at remote sites (< 0.2 µg m−3 and highest in the areas with intensive agriculture (up to 22 µg m−3, while NH4+ concentrations show less spatial variability (e.g. range of 0.14 to 1.8 µg m−3 annual mean in 2005. Temporally, NH3 concentrations are influenced by environmental conditions and local emission sources. In particular, peak NH3 concentrations are observed in summer at background sites (defined by 5 km grid average NH3 emissions < 1 kg N ha−1 yr−1 and in areas dominated by sheep farming, driven by increased volatilization of NH3 in warmer summer temperatures. In areas where cattle, pig and poultry farming is dominant, the largest NH3 concentrations are in spring and autumn, matching periods of manure application to fields. By contrast, peak concentrations of NH4+ aerosol occur in spring, associated with long-range transboundary sources. An estimated decrease in NH3 emissions by 16 % between 1998 and 2014 was reported by the UK National Atmospheric Emissions Inventory. Annually averaged NH3 data from NAMN sites operational over the same period (n =  59 show an indicative downward trend, although the reduction in NH3 concentrations is smaller and non-significant: Mann–Kendall (MK, −6.3 %; linear regression (LR, −3.1 %. In areas dominated by pig and poultry farming, a significant reduction in NH3 concentrations between 1998 and 2014 (MK: −22 %; LR: −21 %, annually averaged NH3 is consistent with, but not as large as the decrease in estimated NH3 emissions from this sector over the same period (−39 %. By contrast, in cattle

  1. Spatial and Temporal Inter-Relationship between Anomalies and Trends of Temperature, Moisture, Cloud Cover and OLR as Observed by AIRS/AMSU on Aqua

    Science.gov (United States)

    Susskind, Joel; Molnar, Gyula

    2009-01-01

    AIRS/AMSU is the advanced IR/MW atmospheric sounding system launched on EOS Aqua in May 2002. Products derived from AIRS/AMSU by the AIRS Science Team include surface skin temperature and atmospheric temperature profiled; atmospheric humidity profiles, fractional cloud clover and cloud top pressure, and OLR. Products covering the period September 2002 through the present have been derived from AIRS/AMSU using the AIRS Science Team Version 5 retrieval algorithm. In this paper, we will show results covering the time period September 2006 - November 2008. This time period is marked by a substantial warming trend of Northern Hemisphere Extra-tropical land surface skin temperatures, as well as pronounced El Nino - La Nina episodes. These both influence the spatial and temporal anomaly patterns of atmospheric temperature and moisture profiles, as well as of cloud cover and Clear Sky and All Sky OLR. The relationships between temporal and spatial anomalies of these parameters over this time period, as determined from AIRS/AMSU observations, will be shown with particular emphasis on which contribute significantly to OLR anomalies in each of the tropics and extra-tropics. Results will also be shown to evaluate the anomalies and trends of temperature profiles and OLR as determined from analysis of AIRS/AMSU data. Global and regional trends during the 6 1/3 year time period are not necessarily indicative of what has happened in the past, or what may happen in the future. Nevertheless, the inter-relationships of spatial and temporal anomalies of atmospheric geophysical parameters with those of surface skin temperature are indicative of climate processes, and can be used to test the performance of climate models when driven by changes in surface temperatures.

  2. Precipitation and Evaporation Trends in Texas

    Science.gov (United States)

    Dixon, R. W.

    2009-05-01

    Texas is a large land area with at least three different climate types. As such it is expected that the results of climate change will not be homogenous. This paper presents results of a study of long trends in Texas precipitation and evaporation using data from the US Historical Climatology Network and the Texas Water Development Board. It shows that the long term trends of these variables is not homogenous and exhibits great variability in both spatial extent and magnitude. This variability must be considered in planning for future water supply or other mitigation projects.

  3. An analysis of trends in spatial mobility of Dutch graduates

    NARCIS (Netherlands)

    Venhorst, Viktor; Van Dijk, Jouke; Van Wissen, Leo

    Considerable attention in the literature has been devoted to spatial mobility as a mechanism in the transition from study to work. In this paper, the relationships between migration and both regional economic circumstances and individual characteristics are investigated using a micro-dataset on

  4. Spatial and temporal trends in occurrence of emerging and legacy contaminants in the Lower Columbia River 2008-2010

    Science.gov (United States)

    Alvarez, David A.; Perkins, Stephanie D.; Nilsen, Elena B.; Morace, Jennifer L.

    2014-01-01

    The Lower Columbia River in Oregon and Washington, USA, is an important resource for aquatic and terrestrial organisms, agriculture, and commerce. An 86-mile stretch of the river was sampled over a 3 year period in order to determine the spatial and temporal trends in the occurrence and concentration of water-borne organic contaminants. Sampling occurred at 10 sites along this stretch and at 1 site on the Willamette River using the semipermeable membrane device (SPMD) and the polar organic chemical integrative sampler (POCIS) passive samplers. Contaminant profiles followed the predicted trends of lower numbers of detections and associated concentrations in the rural areas to higher numbers and concentrations at the more urbanized sites. Industrial chemicals, plasticizers, and PAHs were present at the highest concentrations. Differences in concentrations between sampling periods were related to the amount of rainfall during the sampling period. In general, water concentrations of wastewater-related contaminants decreased and concentrations of legacy contaminants slightly increased with increasing rainfall amounts.

  5. Spatio-temporal trend analysis of precipitation in Guizhou province based on GIS technology

    Science.gov (United States)

    Wu, Jianfeng; Zhang, Fengtai; Pan, Yuanfen; Li, Wei; Cao, Guangjie; An, Youzhi

    2018-02-01

    Precipitation changes are closely related to human production and life. Based on the data of Guizhou Province from 1998 to 2012, the temporal and spatial characteristics of precipitation in Guizhou Province were analyzed from the annual, seasonal and monthly scales by linear trend analysis and ArcGIS kriging spatial interpolation. The results show that the annual precipitation is mainly concentrated in the summer, accounting for 47.6% of the year, followed by spring accounted for 26.9%, autumn accounted for 18.6% in winter accounted for 6.9%. In the time, the precipitation in the study area shows a decreasing trend in the annual scale, seasonal scale and July. The overall spatial precipitation distribution shows a decreasing trend from the east to the west. The precipitation also in the south is higher than the northern region.

  6. Spatial patterns and recent trends in the climate of tropical rainforest regions.

    Science.gov (United States)

    Malhi, Yadvinder; Wright, James

    2004-03-29

    We present an analysis of the mean climate and climatic trends of tropical rainforest regions over the period 1960-1998, with the aid of explicit maps of forest cover and climatological databases. Until the mid-1970s most regions showed little trend in temperature, and the western Amazon experienced a net cooling probably associated with an interdecadal oscillation. Since the mid-1970s, all tropical rainforest regions have experienced a strong warming at a mean rate of 0.26 +/- 0.05 degrees C per decade, in synchrony with a global rise in temperature that has been attributed to the anthropogenic greenhouse effect. Over the study period, precipitation appears to have declined in tropical rainforest regions at a rate of 1.0 +/- 0.8% per decade (p Africa (at 3-4% per decade), declining marginally in tropical Asia and showing no significant trend in Amazonia. There is no evidence so far of a decline in precipitation in eastern Amazonia, a region thought vulnerable to climate-change-induced drying. The strong drying trend in Africa suggests that this should be a priority study region for understanding the impact of drought on tropical rainforests. We develop and use a dry-season index to study variations in the length and intensity of the dry season. Only African and Indian tropical rainforests appear to have seen a significant increase in dry-season intensity. In terms of interannual variability, the El Niño-Southern Oscillation (ENSO) is the primary driver of temperature variations across the tropics and of precipitation fluctuations for large areas of the Americas and southeast Asia. The relation between ENSO and tropical African precipitation appears less direct.

  7. Penguin Bank: A Loa-Trend Hawaiian Volcano

    Science.gov (United States)

    Xu, G.; Blichert-Toft, J.; Clague, D. A.; Cousens, B.; Frey, F. A.; Moore, J. G.

    2007-12-01

    Hawaiian volcanoes along the Hawaiian Ridge from Molokai Island in the northwest to the Big Island in the southeast, define two parallel trends of volcanoes known as the Loa and Kea spatial trends. In general, lavas erupted along these two trends have distinctive geochemical characteristics that have been used to define the spatial distribution of geochemical heterogeneities in the Hawaiian plume (e.g., Abouchami et al., 2005). These geochemical differences are well established for the volcanoes forming the Big Island. The longevity of the Loa- Kea geochemical differences can be assessed by studying East and West Molokai volcanoes and Penguin Bank which form a volcanic ridge perpendicular to the Loa and Kea spatial trends. Previously we showed that East Molokai volcano (~1.5 Ma) is exclusively Kea-like and that West Molokai volcano (~1.8 Ma) includes lavas that are both Loa- and Kea-like (Xu et al., 2005 and 2007).The submarine Penguin Bank (~2.2 Ma), probably an independent volcano constructed west of West Molokai volcano, should be dominantly Loa-like if the systematic Loa and Kea geochemical differences were present at ~2.2 Ma. We have studied 20 samples from Penguin Bank including both submarine and subaerially-erupted lavas recovered by dive and dredging. All lavas are tholeiitic basalt representing shield-stage lavas. Trace element ratios, such as Sr/Nb and Zr/Nb, and isotopic ratios of Sr and Nd clearly are Loa-like. On an ɛNd-ɛHf plot, Penguin Bank lavas fall within the field defined by Mauna Loa lavas. Pb isotopic data lie near the Loa-Kea boundary line defined by Abouchami et al. (2005). In conclusion, we find that from NE to SW, i.e., perpendicular to the Loa and Kea spatial trend, there is a shift from Kea-like East Molokai lavas to Loa-like Penguin Bank lavas with the intermediate West Molokai volcano having lavas with both Loa- and Kea-like geochemical features. Therefore, the Loa and Kea geochemical dichotomy exhibited by Big Island volcanoes

  8. Mixed model with spatial variance-covariance structure for accommodating of local stationary trend and its influence on multi-environmental crop variety trial assessment

    Energy Technology Data Exchange (ETDEWEB)

    Negash, A. W.; Mwambi, H.; Zewotir, T.; Eweke, G.

    2014-06-01

    The most common procedure for analyzing multi-environmental trials is based on the assumption that the residual error variance is homogenous across all locations considered. However, this may often be unrealistic, and therefore limit the accuracy of variety evaluation or the reliability of variety recommendations. The objectives of this study were to show the advantages of mixed models with spatial variance-covariance structures, and direct implications of model choice on the inference of varietal performance, ranking and testing based on two multi-environmental data sets from realistic national trials. A model comparison with a {chi}{sup 2}-test for the trials in the two data sets (wheat data set BW00RVTI and barley data set BW01RVII) suggested that selected spatial variance-covariance structures fitted the data significantly better than the ANOVA model. The forms of optimally-fitted spatial variance-covariance, ranking and consistency ratio test were not the same from one trial (location) to the other. Linear mixed models with single stage analysis including spatial variance-covariance structure with a group factor of location on the random model also improved the real estimation of genotype effect and their ranking. The model also improved varietal performance estimation because of its capacity to handle additional sources of variation, location and genotype by location (environment) interaction variation and accommodating of local stationary trend. (Author)

  9. Spatial configuration trends in coastal Louisiana from 1985 to 2010

    Science.gov (United States)

    Couvillion, Brady; Fischer, Michelle; Beck, Holly J.; Sleavin, William J.

    2016-01-01

    From 1932 to 2010, coastal Louisiana has experienced a net loss of 4877 km2 of wetlands. As the area of these wetlands has changed, so too has the spatial configuration of the landscape. The resulting landscape is a mosaic of patches of wetlands and open water. This study examined the spatial and temporal variability of trajectories of landscape configuration and the relation of those patterns to the trajectories of land change in wetlands during a 1985–2010 observation period. Spatial configuration was quantified using multi-temporal satellite imagery and an aggregation index (AI). The results of this analysis indicate that coastal Louisiana experienced a reduction in the AI of coastal wetlands of 1.07 %. In general, forested wetland and fresh marsh types displayed the highest aggregation and stability. The remaining marsh types, (intermediate, brackish, and saline) all experienced disaggregation during the time period, with increasing severity of disaggregation along an increasing salinity gradient. Finally, a correlation (r 2 = 0.5562) was found between AI and the land change rate for the subsequent period, indicating that fragmentation can increase the vulnerability of wetlands to further wetland loss. These results can help identify coastal areas which are susceptible to future wetland loss.

  10. Improved Density Based Spatial Clustering of Applications of Noise Clustering Algorithm for Knowledge Discovery in Spatial Data

    Directory of Open Access Journals (Sweden)

    Arvind Sharma

    2016-01-01

    Full Text Available There are many techniques available in the field of data mining and its subfield spatial data mining is to understand relationships between data objects. Data objects related with spatial features are called spatial databases. These relationships can be used for prediction and trend detection between spatial and nonspatial objects for social and scientific reasons. A huge data set may be collected from different sources as satellite images, X-rays, medical images, traffic cameras, and GIS system. To handle this large amount of data and set relationship between them in a certain manner with certain results is our primary purpose of this paper. This paper gives a complete process to understand how spatial data is different from other kinds of data sets and how it is refined to apply to get useful results and set trends to predict geographic information system and spatial data mining process. In this paper a new improved algorithm for clustering is designed because role of clustering is very indispensable in spatial data mining process. Clustering methods are useful in various fields of human life such as GIS (Geographic Information System, GPS (Global Positioning System, weather forecasting, air traffic controller, water treatment, area selection, cost estimation, planning of rural and urban areas, remote sensing, and VLSI designing. This paper presents study of various clustering methods and algorithms and an improved algorithm of DBSCAN as IDBSCAN (Improved Density Based Spatial Clustering of Application of Noise. The algorithm is designed by addition of some important attributes which are responsible for generation of better clusters from existing data sets in comparison of other methods.

  11. Studies of fracture network geometry of reservoir outcrop analogues from terrestrial lidar data: attempts to quantify spatial variations of fracture characteristics

    Science.gov (United States)

    Vsemirnova, E. A.; Jones, R. R.; McCaffrey, K. J. W.

    2012-04-01

    We describe studies analysing terrestrial lidar datasets of fracture systems from a range of reservoir analogues in clastic and carbonate lithologies that represent geological analogues of offshore hydrocarbon reservoirs for the UK continental shelf. As fracture networks (observed here from centimetre to kilometre scale) can significantly affect the permeability of a fractured reservoir, the definition of fracture network geometry at various scales has become an important goal of structural analysis. The main aim of the study has been to extend the investigation of fracture networks in order to quantify spatial variations in fracture parameters in a variety of lithologies. The datasets were pre-processed using RiSCAN PRO software, and then re-sampled and filtered to derive characteristics which are traditionally measured from outcrops, including size distributions, fracture spacing and clustering statistics. This type of analysis can significantly reduce the uncertainty associated with some field fracture network measurements. The digitised fracture networks datasets are then used to investigate various aspects of spatial heterogeneity. A series of fracture maps (joints and faults) were generated at different scales, and fracture trends were studied to test scale dependency of fracture orientations. Multiscale trend analysis was then applied to describe the trend structure of the fracture networks.

  12. Urban sprawl and fragmentation in Latin America: a dynamic quantification and characterization of spatial patterns.

    Science.gov (United States)

    Inostroza, Luis; Baur, Rolf; Csaplovics, Elmar

    2013-01-30

    South America is one of the most urbanized continents in the world, where almost 84% of the total population lives in cities, more urbanized than North America (82%) and Europe (73%). Spatial dynamics, their structure, main features, land consumption rates, spatial arrangement, fragmentation degrees and comparability, remain mostly unknown for most Latin American cities. Using satellite imagery the main parameters of sprawl are quantified for 10 Latin American cities over a period of 20 years by monitoring growth patterns and identifying spatial metrics to characterize urban development and sprawling features measured with GIS tools. This quantification contributes to a better understanding of urban form in Latin America. A pervasive spatial expansion has been observed, where most of the studied cities are expanding at fast rates with falling densities trend. Although important differences in the rates of land consumption and densities exist, there is an underlying fragmentation trend towards increasing sprawl. These trends of spatial discontinuity may eventually be intensified by further economic development. Urban Sprawl/Latin America/GIS metrics/spatial development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. A climatic deconstruction of recent drought trends in the United States

    International Nuclear Information System (INIS)

    Ficklin, Darren L; Maxwell, Justin T; Gholizadeh, Hamed; Letsinger, Sally L

    2015-01-01

    We present high spatial-resolution trends of the Palmer drought severity index (PDSI), potential evapotranspiration (PET), and selected climate variables from 1979–2013 for the contiguous United States in order to gain an understanding of recent drought trends and their climatic forcings. Based on a spatial grouping analysis, four regions of increasing (upper Midwest, Louisiana, southeastern United States (US), and western US) and decreasing (New England, Pacific Northwest, upper Great Plains, and Ohio River Valley) drought trends based on Mann–Kendall Z values were found. Within these regions, partial correlation and multiple regression for trends in climate variables and PDSI were performed to examine potential climatic controls on these droughts. As expected, there was a US-wide concurrence on drought forcing by precipitation. However, there was correspondence of recent PET trends with recent drought trends in many regions. For regions with an increase in recent droughts, average air temperature was generally the second most important variable after precipitation in determining recent drought trends. Across the regions where recent drought trends are decreasing, there was no clear ranking of climate-variable importance, where trends in average temperature, specific humidity and net radiation all played significant regional roles in determining recent drought trends. Deconstructing the trends in drought show that, while there are regions in the US showing positive and negative trends in drought conditions, the climate forcings for these drought trends are regionally specific. The results of this study allow for the interpretation of the role of the changing hydroclimatic cycle in recent drought trends, which also have implications for the current and impending results of climate change. (letter)

  14. Characterizing uncertainties in recent trends of global terrestrial net primary production through ensemble modeling

    Science.gov (United States)

    Wang, W.; Hashimoto, H.; Ganguly, S.; Votava, P.; Nemani, R. R.; Myneni, R. B.

    2010-12-01

    Large uncertainties exist in our understanding of the trends and variability in global net primary production (NPP) and its controls. This study attempts to address this question through a multi-model ensemble experiment. In particular, we drive ecosystem models including CASA, LPJ, Biome-BGC, TOPS-BGC, and BEAMS with a long-term climate dataset (i.e., CRU-NCEP) to estimate global NPP from 1901 to 2009 at a spatial resolution of 0.5 x 0.5 degree. We calculate the trends of simulated NPP during different time periods and test their sensitivities to climate variables of solar radiation, air temperature, precipitation, vapor pressure deficit (VPD), and atmospheric CO2 levels. The results indicate a large diversity among the simulated NPP trends over the past 50 years, ranging from nearly no trend to an increasing trend of ~0.1 PgC/yr. Spatial patterns of the NPP generally show positive trends in boreal forests, induced mainly by increasing temperatures in these regions; they also show negative trends in the tropics, although the spatial patterns are more diverse. These diverse trends result from different climatic sensitivities of NPP among the tested models. Depending the ecological processes (e.g., photosynthesis or respiration) a model emphasizes, it can be more or less responsive to changes in solar radiation, temperatures, water, or atmospheric CO2 levels. Overall, these results highlight the limit of current ecosystem models in simulating NPP, which cannot be easily observed. They suggest that the traditional single-model approach is not ideal for characterizing trends and variability in global carbon cycling.

  15. Spatial and topographic trends in forest expansion and biomass change, from regional to local scales.

    Science.gov (United States)

    Buma, Brian; Barrett, Tara M

    2015-09-01

    Natural forest growth and expansion are important carbon sequestration processes globally. Climate change is likely to increase forest growth in some regions via CO2 fertilization, increased temperatures, and altered precipitation; however, altered disturbance regimes and climate stress (e.g. drought) will act to reduce carbon stocks in forests as well. Observations of asynchrony in forest change is useful in determining current trends in forest carbon stocks, both in terms of forest density (e.g. Mg ha(-1) ) and spatially (extent and location). Monitoring change in natural (unmanaged) areas is particularly useful, as while afforestation and recovery from historic land use are currently large carbon sinks, the long-term viability of those sinks depends on climate change and disturbance dynamics at their particular location. We utilize a large, unmanaged biome (>135 000 km(2) ) which spans a broad latitudinal gradient to explore how variation in location affects forest density and spatial patterning: the forests of the North American temperate rainforests in Alaska, which store >2.8 Pg C in biomass and soil, equivalent to >8% of the C in contiguous US forests. We demonstrate that the regional biome is shifting; gains exceed losses and are located in different spatio-topographic contexts. Forest gains are concentrated on northerly aspects, lower elevations, and higher latitudes, especially in sheltered areas, whereas loss is skewed toward southerly aspects and lower latitudes. Repeat plot-scale biomass data (n = 759) indicate that within-forest biomass gains outpace losses (live trees >12.7 cm diameter, 986 Gg yr(-1) ) on gentler slopes and in higher latitudes. This work demonstrates that while temperate rainforest dynamics occur at fine spatial scales (biomass accumulation suggest the potential for relatively rapid biome shifts and biomass changes. © 2015 John Wiley & Sons Ltd.

  16. Spatial and Temporal Trends of Global Pollination Benefit

    Science.gov (United States)

    Lautenbach, Sven; Seppelt, Ralf; Liebscher, Juliane; Dormann, Carsten F.

    2012-01-01

    Pollination is a well-studied and at the same time a threatened ecosystem service. A significant part of global crop production depends on or profits from pollination by animals. Using detailed information on global crop yields of 60 pollination dependent or profiting crops, we provide a map of global pollination benefits on a 5′ by 5′ latitude-longitude grid. The current spatial pattern of pollination benefits is only partly correlated with climate variables and the distribution of cropland. The resulting map of pollination benefits identifies hot spots of pollination benefits at sufficient detail to guide political decisions on where to protect pollination services by investing in structural diversity of land use. Additionally, we investigated the vulnerability of the national economies with respect to potential decline of pollination services as the portion of the (agricultural) economy depending on pollination benefits. While the general dependency of the agricultural economy on pollination seems to be stable from 1993 until 2009, we see increases in producer prices for pollination dependent crops, which we interpret as an early warning signal for a conflict between pollination service and other land uses at the global scale. Our spatially explicit analysis of global pollination benefit points to hot spots for the generation of pollination benefits and can serve as a base for further planning of land use, protection sites and agricultural policies for maintaining pollination services. PMID:22563427

  17. Recent change of vegetation growth trend in China

    International Nuclear Information System (INIS)

    Peng Shushi; Fang Jingyun; Piao Shilong; Chen, Anping; Xu Liang; Myneni, Ranga B; Cao Chunxiang; Pinzon, Jorge E; Tucker, Compton J

    2011-01-01

    Using satellite-derived normalized difference vegetation index (NDVI) data, several previous studies have indicated that vegetation growth significantly increased in most areas of China during the period 1982–99. In this letter, we extended the study period to 2010. We found that at the national scale the growing season (April–October) NDVI significantly increased by 0.0007 yr −1 from 1982 to 2010, but the increasing trend in NDVI over the last decade decreased in comparison to that of the 1982–99 period. The trends in NDVI show significant seasonal and spatial variances. The increasing trend in April and May (AM) NDVI (0.0013 yr −1 ) is larger than those in June, July and August (JJA) (0.0003 yr −1 ) and September and October (SO) (0.0008 yr −1 ). This relatively small increasing trend of JJA NDVI during 1982–2010 compared with that during 1982–99 (0.0012 yr −1 ) (Piao et al 2003 J. Geophys. Res.—Atmos. 108 4401) implies a change in the JJA vegetation growth trend, which significantly turned from increasing (0.0039 yr −1 ) to slightly decreasing ( − 0.0002 yr −1 ) in 1988. Regarding the spatial pattern of changes in NDVI, the growing season NDVI increased (over 0.0020 yr −1 ) from 1982 to 2010 in southern China, while its change was close to zero in northern China, as a result of a significant changing trend reversal that occurred in the 1990s and early 2000s. In northern China, the growing season NDVI significantly increased before the 1990s as a result of warming and enhanced precipitation, but decreased after the 1990s due to drought stress strengthened by warming and reduced precipitation. Our results also show that the responses of vegetation growth to climate change vary across different seasons and ecosystems.

  18. Recent Change of Vegetation Growth Trend in China

    Science.gov (United States)

    Peng, Shushi; Chen, Anping; Xu, Liang; Cao, Chunxiang; Fang, Jingyun; Myneni, Ranga B.; Pinzon, Jorge E.; Tucker, COmpton J.; Piao, Shilong

    2011-01-01

    Using satellite-derived normalized difference vegetation index (NDVI) data, several previous studies have indicated that vegetation growth significantly increased in most areas of China during the period 1982-99. In this letter, we extended the study period to 2010. We found that at the national scale the growing season (April-October) NDVI significantly increased by 0.0007/yr from 1982 to 2010, but the increasing trend in NDVI over the last decade decreased in comparison to that of the 1982-99 period. The trends in NDVI show significant seasonal and spatial variances. The increasing trend in April and May (AM) NDVI (0.0013/yr is larger than those in June, July and August (JJA) (0.0003/yr) and September and October (SO) (0.0008/yr). This relatively small increasing trend of JJA NDVI during 1982-2010 compared with that during 1982-99 (0.0012/yr) (Piao et al 2003 J. Geophys. Res.-Atmos. 108 4401) implies a change in the JJA vegetation growth trend, which significantly turned from increasing (0.0039/yr) to slightly decreasing (0:0002/yr) in 1988. Regarding the spatial pattern of changes in NDVI, the growing season NDVI increased (over 0.0020/yr) from 1982 to 2010 in southern China, while its change was close to zero in northern China, as a result of a significant changing trend reversal that occurred in the 1990s and early 2000s. In northern China, the growing season NDVI significantly increased before the 1990s as a result of warming and enhanced precipitation, but decreased after the 1990s due to drought stress strengthened by warming and reduced precipitation. Our results also show that the responses of vegetation growth to climate change vary across different seasons and ecosystems.

  19. Space-time trends in U.S. meteorological droughts

    Directory of Open Access Journals (Sweden)

    Poulomi Ganguli

    2016-12-01

    New hydrological insights for the region: The paper finds spatial coverage of extreme meteorological drought in the recent years (post-2010 exceeds that of the iconic droughts of the 1930s (the Dust Bowl era, and the 1950s. These results are in contrast with trends in spatial variance that does not exhibit any statistically significant trend. In addition, we find drought persistence remains relatively stationary over the last half century. The findings can inform drought monitoring and planning, and improve future drought resilience.

  20. A comprehensive emission inventory of multiple air pollutants from iron and steel industry in China: Temporal trends and spatial variation characteristics.

    Science.gov (United States)

    Wang, Kun; Tian, Hezhong; Hua, Shenbing; Zhu, Chuanyong; Gao, Jiajia; Xue, Yifeng; Hao, Jiming; Wang, Yong; Zhou, Junrui

    2016-07-15

    China has become the largest producer of iron and steel throughout the world since 1996. However, as an energy-and-pollution intensive manufacturing sector, a detailed comprehensive emission inventory of air pollutants for iron and steel industry of China is still not available. To obtain and better understand the temporal trends and spatial variation characteristics of typical hazardous air pollutants (HAPs) emissions from iron and steel production in China, a comprehensive emission inventory of multiple air pollutants, including size segregated particulate matter (TSP/PM10/PM2.5), gaseous pollutants (SO2, NOx, CO), heavy metals (Pb, Cd, Hg, As, Cr, Ni etc.), as well as the more dangerous PCDD/Fs, is established with the unit-based annual activity, specific dynamic emission factors for the historical period of 1978-2011, and the future potential trends till to 2050 are forecasted by using scenario analysis. Our results show that emissions of gaseous pollutants and particulate matter have experienced a gradual increase tendency since 2000, while emissions of priority-controlled heavy metals (Hg, Pb, As, Cd, Cr, and Ni) have exhibited a short-term fluctuation during the period of 1990 to 2005. With regard to the spatial distribution of HAPs emissions in base year 2011, Bohai economic circle is identified as the top emission intensity region where iron and steel smelting plants are densely built; within iron and steel industry, blast furnaces contribute the majority of PM emissions, sinter plants account for most of gaseous pollutants and the majority of PCDD/Fs, whereas steel making processes are responsible for the majority of heavy metal emissions. Moreover, comparisons of future emission trends under three scenarios indicate that advanced technologies and integrated whole process management strategies are in great need to further diminish various hazardous air pollutants from iron and steel industry in the future. Copyright © 2016 Elsevier B.V. All rights

  1. A retrospective study and predictive modelling of Newcastle Disease trends among rural poultry of eastern Zambia.

    Science.gov (United States)

    Mubamba, C; Ramsay, G; Abolnik, C; Dautu, G; Gummow, B

    2016-10-01

    Newcastle Disease (ND) is a highly infectious disease of poultry that seriously impacts on food security and livelihoods of livestock farmers and communities in tropical regions of the world. ND is a constant problem in the eastern province of Zambia which has more than 740 000 rural poultry. Very few studies give a situational analysis of the disease that can be used for disease control planning in the region. With this background in mind, a retrospective epidemiological study was conducted using Newcastle Disease data submitted to the eastern province headquarters for the period from 1989 to 2014. The study found that Newcastle Disease cases in eastern Zambia followed a seasonal and cyclic pattern with peaks in the hot dry season (Overall Seasonal Index 1.1) as well as cycles every three years with an estimated provincial incidence range of 0.16 to 1.7% per year. Annual trends were compared with major intervention policies implemented by the Zambian government, which often received donor support from the international community during the study period. Aid delivered through government programmes appeared to have no major impact on ND trends between 1989 and 2014 and reasons for this are discussed. There were apparent spatial shifts in districts with outbreaks over time which could be as a result of veterinary interventions chasing outbreaks rather than implementing uniform control. Data was also fitted to a predictive time series model for ND which could be used to plan for future ND control. Time series modelling showed an increasing trend in ND annual incidence over 25 years if existing interventions continue. A different approach to controlling the disease is needed if this trend is to be halted. Conversely, the positive trend may be a function of improved reporting by farmers as a result of more awareness of the disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Trends of precipitation characteristics in the Czech Republic over 1961–2012, their spatial patterns and links to temperature and the North Atlantic Oscillation

    Czech Academy of Sciences Publication Activity Database

    Beranová, Romana; Kyselý, Jan

    (2017) ISSN 0899-8418 R&D Projects: GA ČR(CZ) GA16-04676S Institutional support: RVO:68378289 Keywords : precipitation * trend analysis * spatial pattern * temperature * the North Atlantic Oscillation * the Czech Republic Subject RIV: DG - Athmosphere Sciences, Meteorology OBOR OECD: Meteorology and atmospheric sciences Impact factor: 3.760, year: 2016 http://onlinelibrary.wiley.com/doi/10.1002/joc.5392/full

  3. Persistent organic pollutants and mercury in marine biota of the Canadian Arctic: an overview of spatial and temporal trends.

    Science.gov (United States)

    Braune, B M; Outridge, P M; Fisk, A T; Muir, D C G; Helm, P A; Hobbs, K; Hoekstra, P F; Kuzyk, Z A; Kwan, M; Letcher, R J; Lockhart, W L; Norstrom, R J; Stern, G A; Stirling, I

    2005-12-01

    This review summarizes and synthesizes the significant amount of data which was generated on mercury (Hg) and persistent organic pollutants (POPs) in Canadian Arctic marine biota since the first Canadian Arctic Contaminants Assessment Report (CACAR) was published in 1997. This recent body of work has led to a better understanding of the current levels and spatial and temporal trends of contaminants in biota, including the marine food species that northern peoples traditionally consume. Compared to other circumpolar countries, concentrations of many organochlorines (OCs) in Canadian Arctic marine biota are generally lower than in the European Arctic and eastern Greenland but are higher than in Alaska, whereas Hg concentrations are substantially higher in Canada than elsewhere. Spatial coverage of OCs in ringed seals, beluga and seabirds remains a strength of the Arctic contaminant data set for Canada. Concentrations of OCs in marine mammals and seabirds remain fairly consistent across the Canadian Arctic although subtle differences from west to east and south to north are found in the proportions of various chemicals. The most significant development since 1997 is improvement in the temporal trend data sets, thanks to the use of archived tissue samples from the 1970s and 1980s, long-term studies using archeological material, as well as the continuation of sampling. These data cover a range of species and chemicals and also include retrospective studies on new chemicals such as polybrominated diphenyl ethers. There is solid evidence in a few species (beluga, polar bear, blue mussels) that Hg at some locations has significantly increased from pre-industrial times to the present; however, the temporal trends of Hg over the past 20-30 years are inconsistent. Some animal populations exhibited significant increases in Hg whereas others did not. Therefore, it is currently not possible to determine if anthropogenic Hg is generally increasing in Canadian Arctic biota. It is

  4. Spatial analysis of binary health indicators with local smoothing techniques The Viadana study.

    Science.gov (United States)

    Girardi, Paolo; Marcon, Alessandro; Rava, Marta; Pironi, Vanda; Ricci, Paolo; de Marco, Roberto

    2012-01-01

    When pollution data from a monitoring network is not available, mapping the spatial distribution of disease can be useful to identify populations at risk and to suggest a potential role for suspected emission sources. We aimed at obtaining a continuous spatial representation of the prevalence of symptoms that are potentially associated with the exposure to the pollutants emitted from the wood factories in the children who live in the district of Viadana (Northern Italy). In 2006, all the parents of the children aged 3-14 years residing in the Viadana district (n = 3854), filled in a questionnaire on respiratory symptoms, irritation symptoms of the eyes and skin, use of health services. The children's residential addresses were also collected and geocoded. Generalized additive models and local weighted regression (LOWESS) were used to estimate the distribution of the symptoms, to test for spatial trends of the symptoms' prevalence and to control for potential confounders. Permutation tests were used to identify the areas of significantly increased risk ("hot spots"). The prevalence of respiratory symptoms, eye symptoms and the use of health services showed a statistically significant spatial variation (p big chipboard industries were located. Hot spots were identified fairly near to one of the two chipboard industries in the district. The north-to-south trend in the prevalence of respiratory and eye symptoms, but not of skin symptoms, as well as the location of hot spots, are consistent with the potential exposure to air pollutants both emitted by the wood factories and related to traffic. In these "high risk areas" monitoring of pollution and preventive actions are clearly needed. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  5. Comparing Spatial Predictions

    KAUST Repository

    Hering, Amanda S.

    2011-11-01

    Under a general loss function, we develop a hypothesis test to determine whether a significant difference in the spatial predictions produced by two competing models exists on average across the entire spatial domain of interest. The null hypothesis is that of no difference, and a spatial loss differential is created based on the observed data, the two sets of predictions, and the loss function chosen by the researcher. The test assumes only isotropy and short-range spatial dependence of the loss differential but does allow it to be non-Gaussian, non-zero-mean, and spatially correlated. Constant and nonconstant spatial trends in the loss differential are treated in two separate cases. Monte Carlo simulations illustrate the size and power properties of this test, and an example based on daily average wind speeds in Oklahoma is used for illustration. Supplemental results are available online. © 2011 American Statistical Association and the American Society for Qualitys.

  6. Depth-time interpolation of feature trends extracted from mobile microelectrode data with kernel functions.

    Science.gov (United States)

    Wong, Stephen; Hargreaves, Eric L; Baltuch, Gordon H; Jaggi, Jurg L; Danish, Shabbar F

    2012-01-01

    Microelectrode recording (MER) is necessary for precision localization of target structures such as the subthalamic nucleus during deep brain stimulation (DBS) surgery. Attempts to automate this process have produced quantitative temporal trends (feature activity vs. time) extracted from mobile MER data. Our goal was to evaluate computational methods of generating spatial profiles (feature activity vs. depth) from temporal trends that would decouple automated MER localization from the clinical procedure and enhance functional localization in DBS surgery. We evaluated two methods of interpolation (standard vs. kernel) that generated spatial profiles from temporal trends. We compared interpolated spatial profiles to true spatial profiles that were calculated with depth windows, using correlation coefficient analysis. Excellent approximation of true spatial profiles is achieved by interpolation. Kernel-interpolated spatial profiles produced superior correlation coefficient values at optimal kernel widths (r = 0.932-0.940) compared to standard interpolation (r = 0.891). The choice of kernel function and kernel width resulted in trade-offs in smoothing and resolution. Interpolation of feature activity to create spatial profiles from temporal trends is accurate and can standardize and facilitate MER functional localization of subcortical structures. The methods are computationally efficient, enhancing localization without imposing additional constraints on the MER clinical procedure during DBS surgery. Copyright © 2012 S. Karger AG, Basel.

  7. Statistical trend of radiation chemical studies

    International Nuclear Information System (INIS)

    Yoshida, Hiroshi

    1980-01-01

    In the field of radiation chemistry, over 1,000 reports are published year after year. Attempt has been made to review the trends in this field for more than five years, by looking through the lists of papers statistically. As for the period from 1974 to 1978, Annual Cumulation with Keyword and Author Indexes in the Biweekly List of Papers on Radiation Chemistry was referred to. For 1979, because of the unavailability of the Cumulation, Chemical Abstracts Search by Japan Information Center of Science and Technology was referred to. The contents are as follows: how far radiation chemistry is studied, what the trends of radiation chemistry is in recent years, who contributes to the advance of radiation chemistry, and where, the trend radiation chemistry takes in 1979. (J.P.N.)

  8. Eye and Hand Movements during Reconstruction of Spatial Memory

    OpenAIRE

    Melanie Rose Burke; Richard Allen; Matilda Webster; Claudia Gonzalez

    2012-01-01

    Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (eg, Awh et al 2006, Trends in Cognitive Sciences 10, 124–130). This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change) from an array presented either simultaneously or sequentially. The time delay between tar...

  9. Trend analysis of hydro-climatic variables in the north of Iran

    Science.gov (United States)

    Nikzad Tehrani, E.; Sahour, H.; Booij, M. J.

    2018-04-01

    Trend analysis of climate variables such as streamflow, precipitation, and temperature provides useful information for understanding the hydrological changes associated with climate change. In this study, a nonparametric Mann-Kendall test was employed to evaluate annual, seasonal, and monthly trends of precipitation and streamflow for the Neka basin in the north of Iran over a 44-year period (1972 to 2015). In addition, the Inverse Distance Weight (IDW) method was used for annual seasonal, monthly, and daily precipitation trends in order to investigate the spatial correlation between precipitation and streamflow trends in the study area. Results showed a downward trend in annual and winter precipitation (Z basin decreased by 14% significantly, but the annual maximum daily flow increased by 118%. Results for the trend analysis of streamflow and climatic variables showed that there are statistically significant relationships between precipitation and streamflow (p value basins (Sefidchah, Gelvard, Abelu). In general, from a hydro-climatic point of view, the results showed that the study area is moving towards a situation with more severe drought events.

  10. Spatial Trends and Variability of Vertical Accretion Rates in the Barataria Basin, Louisiana, U.S.A. using Pb-210 and Cs-137 radiochemistry

    Science.gov (United States)

    Shrull, S.; Wilson, C.; Snedden, G.; Bentley, S. J.

    2017-12-01

    Barataria Basin on the south Louisiana coast is experiencing some of the greatest amounts of coastal land loss in the United States with rates as high as 23.1 km2 lost per year. In an attempt to help slow or reverse land loss, millions of dollars are being spent to create sediment diversions to increase the amount of available inorganic sediments to these vulnerable coastal marsh areas. A better understanding of the spatial trends and patterns of background accretion rates needs to be established in order to effectively implement such structures. Core samples from 25 Coastwide Reference Monitoring System (CRMS) sites spanning inland freshwater to coastal saline areas within the basin were extracted, and using vertical accretion rates from Cs-137 & Pb-210 radionuclide detection, mineral versus organic sediment composition, grain size distribution, and spatial trends of bulk densities, the controls on the accretion rates of the marsh soils will be constrained. Initial rates show a range from 0.31 cm/year to 1.02 cm/year with the average being 0.79 cm/year. Preliminary results suggest that location and proximity to an inorganic sediment source (i.e. river/tributary or open water) have a stronger influence on vertical accretion rates than marsh classification and salinity, with no clear relationship between vertical accretion and salinity. Down-core sediment composition and bulk density analyses observed at a number of the sites likely suggest episodic sedimentation and show different vertical accretion rates through time. Frequency and length of inundation (i.e. hydroperiod), and land/marsh classification from the CRMS data set will be further investigated to constrain the spatial variability in vertical accretion for the basin.

  11. Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds

    International Nuclear Information System (INIS)

    Roscales, Jose L.; Gonzalez-Solis, Jacob; Calabuig, Pascual; Jimenez, Begona

    2011-01-01

    PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels. - Highlights: → PAHs in pelagic seabirds show specific inter-species patterns related to trophic ecology. → Geographic origin shows a minor effect over PAH levels in pelagic seabirds. → Pelagic seabirds seem to be poor indicators of chronic PAH levels. - PAH levels in Atlantic and Mediterranean pelagic seabirds show specific inter-species patterns related to trophic ecology but a minor influence of their geographic origin.

  12. The Hierarchical Trend Model for property valuation and local price indices

    NARCIS (Netherlands)

    Francke, M.K.; Vos, G.A.

    2002-01-01

    This paper presents a hierarchical trend model (HTM) for selling prices of houses, addressing three main problems: the spatial and temporal dependence of selling prices and the dependency of price index changes on housing quality. In this model the general price trend, cluster-level price trends,

  13. Characteristics of Spatial Structural Patterns and Temporal Variability of Annual Precipitation in Ningxia

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the characteristics of the spatial structural patterns and temporal variability of annual precipitation in Ningxia.[Method] Using rotated empirical orthogonal function,the precipitation concentration index,wavelet analysis and Mann-Kendall rank statistic method,the characteristics of precipitation on the spatial-temporal variability and trend were analyzed by the monthly precipitation series in Ningxia during 1951-2008.[Result] In Ningxia,the spatial structural patterns of a...

  14. Temporal and spatial trends for trace metals in streams and rivers across Sweden (1996–2009

    Directory of Open Access Journals (Sweden)

    J. Fölster

    2011-07-01

    Full Text Available Long term data series (1996 through 2009 for trace metals were analyzed from a large number of streams and rivers across Sweden varying in tributary watershed size from 0.05 to 48 193 km2. The final data set included 139 stream sites with data for arsenic (As, cobalt (Co, copper (Cu, chromium (Cr, nickel (Ni, lead (Pb, zinc (Zn, and vanadium (V. Between 7 % and 46 % of the sites analyzed showed significant trends according to the seasonal Kendall test. However, in contrast to previous studies and depositional patterns, a substantial portion of the trends were positive, especially for V (100 %, As (95 %, and Pb (68 %. Other metals (Zn and Cr generally decreased, were mixed (Ni and Zn, or had very few trends (Co over the study period. Trends by region were also analyzed and some showed significant variation between the north and south of Sweden. Regional trends for both Cu and Pb were positive (60 % and 93 %, respectively in the southern region but strongly negative (93 % and 75 %, respectively in the northern region. Kendall's τ coefficients were used to determine dependence between metals and potential in-stream drivers including total organic carbon (TOC, iron (Fe, pH, and sulphate (SO42−. TOC and Fe correlated positively and strongly with As, V, Pb, and Co while pH and SO42− generally correlated weakly, or not at all with the metals studied.

  15. Leftward spatial bias in children's drawing placement: hemispheric activation versus directional hypotheses.

    Science.gov (United States)

    Picard, Delphine; Zarhbouch, Benaissa

    2014-01-01

    A leftward spatial bias in drawing placement was demonstrated by Heller (1991) using the draw-a-person test with right-handed American children. No such bias was observed in left-handed children who are assumed to be less lateralised than their right-handed peers. According to Heller the leftward spatial bias is primarily a reflection of the right hemisphere specialisation for spatial processing. However, an alternative explanation in terms of directional trends may be put forward. In the present study we first confirm Heller's findings of a handedness effect on drawing placement using the draw-a-tree task with a large sample of right- and left-handed French children aged 5-15 years (Exp. 1). We then provide evidence that a similar leftward bias occurs in right-handed Moroccan children aged 7-11 years with opposite script directionality and opposite preferred drawing movement directions (i.e., right-to-left directional trends) to the those of right-handed French children (Exp. 2). Taken together these findings suggest that directionality trends arising from learned cultural habits and motor preferences play little role in determining spatial bias in the centring of a single object drawn on a page. Rather there may be a cerebral origin for drawing single objects slightly on the left side of the graphic space.

  16. Gaseous and Freely-Dissolved PCBs in the Lower Great Lakes Based on Passive Sampling: Spatial Trends and Air-Water Exchange.

    Science.gov (United States)

    Liu, Ying; Wang, Siyao; McDonough, Carrie A; Khairy, Mohammed; Muir, Derek C G; Helm, Paul A; Lohmann, Rainer

    2016-05-17

    Polyethylene passive sampling was performed to quantify gaseous and freely dissolved polychlorinated biphenyls (PCBs) in the air and water of Lakes Erie and Ontario during 2011-2012. In view of differing physical characteristics and the impacts of historical contamination by PCBs within these lakes, spatial variation of PCB concentrations and air-water exchange across these lakes may be expected. Both lakes displayed statistically similar aqueous and atmospheric PCB concentrations. Total aqueous concentrations of 29 PCBs ranged from 1.5 pg L(-1) in the open lake of Lake Erie (site E02) in 2011 spring to 105 pg L(-1) in Niagara (site On05) in 2012 summer, while total atmospheric concentrations were 7.7-634 pg m(-3) across both lakes. A west-to-east gradient was observed for aqueous PCBs in Lake Erie. River discharge and localized influences (e.g., sediment resuspension and regional alongshore transport) likely dominated spatial trends of aqueous PCBs in both lakes. Air-water exchange fluxes of Σ7PCBs ranged from -2.4 (±1.9) ng m(-2) day(-1) (deposition) in Sheffield (site E03) to 9.0 (±3.1) ng m(-2) day(-1) (volatilization) in Niagara (site On05). Net volatilization of PCBs was the primary trend across most sites and periods. Almost half of variation in air-water exchange fluxes was attributed to the difference in aqueous concentrations of PCBs. Uncertainty analysis in fugacity ratios and mass fluxes in air-water exchange of PCBs indicated that PCBs have reached or approached equilibrium only at the eastern Lake Erie and along the Canadian shore of Lake Ontario sites, where air-water exchange fluxes dominated atmospheric concentrations.

  17. Space-time patterns of trends in stratospheric constituents derived from UARS measurements

    Science.gov (United States)

    Randel, William J.; Wu, Fei; Russell, James M.; Waters, Joe

    1999-02-01

    The spatial and temporal behavior of low-frequency changes (trends) in stratospheric constituents measured by instruments on the Upper Atmosphere Research Satellite (UARS) during 1991-98 is investigated. The data include CH4, H2O, HF, HCl, O3, and NO2 from the Halogen Occultation Experiment (HALOE), and O3, ClO, and HNO3 from the Microwave Limb Sounder (MLS). Time series of global anomalies are analyzed by linear regression and empirical orthogonal function analysis. Each of the constituents show significant linear trends over at least some region of the stratosphere, and the spatial patterns exhibit coupling between the different species. Several of the constituents (namely CH4, H2O, HF, HCl, O3, and NO2) exhibit a temporal change in trend rates, with strong changes prior to 1996 and weaker (or reversed) trends thereafter. Positive trends are observed in upper stratospheric ClO, with a percentage rate during 1993-97 consistent with stratospheric HCl increases and with tropospheric chlorine emission rates. Significant negative trends in ozone in the tropical middle stratosphere are found in both HALOE and MLS data during 1993-97, together with positive trends in the tropics near 25 km. These trends are very different from the decadal-scale ozone trends observed since 1979, and this demonstrates the variability of trends calculated over short time periods. Positive trends in NO2 are found in the tropical middle stratosphere, and spatial coincidence to the observed ozone decreases suggests the ozone is responding to the NO2 increase. Significant negative trends in HNO3 are found in the lower stratosphere of both hemispheres. These coupled signatures offer a fingerprint of chemical evolution in the stratosphere for the UARS time frame.

  18. Crash rates analysis in China using a spatial panel model

    Directory of Open Access Journals (Sweden)

    Wonmongo Lacina Soro

    2017-10-01

    Full Text Available The consideration of spatial externalities in traffic safety analysis is of paramount importance for the success of road safety policies. Yet, the quasi-totality of spatial dependence studies on crash rates is performed within the framework of single-equation spatial cross-sectional studies. The present study extends the spatial cross-sectional scheme to a spatial fixed-effects panel model estimated using the maximum likelihood method. The spatial units are the 31 administrative regions of mainland China over the period 2004–2013. The presence of neighborhood effects is evidenced through the Moran's I statistic. Consistent with previous studies, the analysis reveals that omitting the spatial effects in traffic safety analysis is likely to bias the estimation results. The spatial and error lags are all positive and statistically significant suggesting similarities of crash rates pattern in neighboring regions. Some other explanatory variables, such as freight traffic, the length of paved roads and the populations of age 65 and above are related to higher rates while the opposite trend is observed for the Gross Regional Product, the urban unemployment rate and passenger traffic.

  19. Regional precipitation trend analysis at the Langat River Basin, Selangor, Malaysia

    Science.gov (United States)

    Palizdan, Narges; Falamarzi, Yashar; Huang, Yuk Feng; Lee, Teang Shui; Ghazali, Abdul Halim

    2014-08-01

    Various hydrological and meteorological variables such as rainfall and temperature have been affected by global climate change. Any change in the pattern of precipitation can have a significant impact on the availability of water resources, agriculture, and the ecosystem. Therefore, knowledge on rainfall trend is an important aspect of water resources management. In this study, the regional annual and seasonal precipitation trends at the Langat River Basin, Malaysia, for the period of 1982-2011 were examined at the 95 % level of significance using the regional average Mann-Kendall (RAMK) test and the regional average Mann-Kendall coupled with bootstrap (RAMK-bootstrap) method. In order to identify the homogeneous regions respectively for the annual and seasonal scales, firstly, at-site mean total annual and separately at-site mean total seasonal precipitation were spatialized into 5 km × 5 km grids using the inverse distance weighting (IDW) algorithm. Next, the optimum number of homogeneous regions (clusters) is computed using the silhouette coefficient approach. Next, the homogeneous regions were formed using the K-mean clustering method. From the annual scale perspective, all three regions showed positive trends. However, the application of two methods at this scale showed a significant trend only in the region AC1. The region AC2 experienced a significant positive trend using only the RAMK test. On a seasonal scale, all regions showed insignificant trends, except the regions I1C1 and I1C2 in the Inter-Monsoon 1 (INT1) season which experienced significant upward trends. In addition, it was proven that the significance of trends has been affected by the existence of serial and spatial correlations.

  20. Trends and causes of historical wetland loss in coastal Louisiana

    Science.gov (United States)

    Bernier, Julie

    2013-01-01

    Wetland losses in the northern Gulf Coast region of the United States are so extensive that they represent critical concerns to government environmental agencies and natural resource managers. In Louisiana, almost 3,000 square kilometers (km2) of low-lying wetlands converted to open water between 1956 and 2004, and billions of dollars in State and Federal funding have been allocated for coastal restoration projects intended to compensate for some of those wetland losses. Recent research at the St. Petersburg Coastal and Marine Science Center (SPCMSC) focused on understanding the physical processes and human activities that contributed to historical wetland loss in coastal Louisiana and the spatial and temporal trends of that loss. The physical processes (land-surface subsidence and sediment erosion) responsible for historical wetland loss were quantified by comparing marsh-surface elevations, water depths, and vertical displacements of stratigraphic contacts at 10 study areas in the Mississippi River delta plain and 6 sites at Sabine National Wildlife Refuge (SNWR) in the western chenier plain. The timing and extent of land loss at the study areas was determined by comparing historical maps, aerial photographs, and satellite imagery; the temporal and spatial trends of those losses were compared with historical subsidence rates and hydrocarbon production trends.

  1. A verification study and trend analysis of simulated boundary layer wind fields over Europe

    Energy Technology Data Exchange (ETDEWEB)

    Lindenberg, Janna

    2011-07-01

    Simulated wind fields from regional climate models (RCMs) are increasingly used as a surrogate for observations which are costly and prone to homogeneity deficiencies. Compounding the problem, a lack of reliable observations makes the validation of the simulated wind fields a non trivial exercise. Whilst the literature shows that RCMs tend to underestimate strong winds over land these investigations mainly relied on comparisons with near surface measurements and extrapolated model wind fields. In this study a new approach is proposed using measurements from high towers and a robust validation process. Tower height wind data are smoother and thus more representative of regional winds. As benefit this approach circumvents the need to extrapolate simulated wind fields. The performance of two models using different downscaling techniques is evaluated. The influence of the boundary conditions on the simulation of wind statistics is investigated. Both models demonstrate a reasonable performance over flat homogeneous terrain and deficiencies over complex terrain, such as the Upper Rhine Valley, due to a too coarse spatial resolution ({proportional_to}50 km). When the spatial resolution is increased to 10 and 20 km respectively a benefit is found for the simulation of the wind direction only. A sensitivity analysis shows major deviations of international land cover data. A time series analysis of dynamically downscaled simulations is conducted. While the annual cycle and the interannual variability are well simulated, the models are less effective at simulating small scale fluctuations and the diurnal cycle. The hypothesis that strong winds are underestimated by RCMs is supported by means of a storm analysis. Only two-thirds of the observed storms are simulated by the model using a spectral nudging approach. In addition ''False Alarms'' are simulated, which are not detected in the observations. A trend analysis over the period 1961 - 2000 is conducted

  2. The impacts of emission trends of POPs on human concentration dynamics: Lessons learned from a longitudinal study in Norway (1979-2007).

    Science.gov (United States)

    Nøst, Therese Haugdahl; Sandanger, Torkjel Manning; Nieboer, Evert; Odland, Jon Øyvind; Breivik, Knut

    2017-06-01

    In this short communication, our focus is on the relationship between human concentrations of select persistent organic pollutants (POPs) and environmental emissions. It is based on a longitudinal study (1979-2007) conducted in Norway. Our aim was to extract general insights from observed and predicted temporal trends in human concentrations of 49 POPs to assist in the design and interpretation of future monitoring studies. Despite considerable decline for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) since 1986, the sum of the targeted POPs increased from 1979 until 2001, with per- and polyfluorinated alkyl substances (PFASs) dominating recent blood burden measurements. Specifically, the time trends in serum concentrations of POPs, exemplified by PCB-153, 1,1'-(2,2,2-Trichloroethane-1,1-diyl)bis(4-chlorobenzene) (DDT) and perfluorooctane sulfonic acid (PFOS), resembled the trends in available data on their emissions, production or use. These observations suggest that interpretations of human biomonitoring data on persistent compounds must consider historic emissions, which likely vary spatially across the globe. Based on the different temporal trends observed across POP groups, it is evident that generalizations regarding temporal aspects have limitations. The discussion herein underscores the importance of understanding temporal variations in environmental emissions when designing and interpreting human biomonitoring studies. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Epoch making NIRS studies seen through citation trends

    International Nuclear Information System (INIS)

    Dan, Ippeita

    2009-01-01

    Near-infrared spectroscopy (NIRS) studies through citation trends are investigated of literature concerning only the brain function measurement and its methodology together with NIRS principle, technological development, present state and future view. Investigation is conducted firstly for the survey of important author name of those concerned papers in Web of Science and Google Scholar with search words of NIRS, brain and optical topography as an option. Second, >100 papers of those authors citing any of them are picked up and their papers are ranked in accordance with Web of Science citation number, of which top-nineteen are presented here. Impact and epoch making papers are reviewed with explanations of: the establishment of measuring technology of cerebral blood flow change and subsequent brain function by NIRS; development with multi-channel detection; simultaneous measurement with other imaging modalities; examination of NIRS validity; spatial analysis of NIRS; and measurement of brain function. The highest times of citation are 1,238 of the paper by F. F. Jobsis in 'Science' (1977). It should be noted that 10 of top 19 papers are those by Japanese authors. However, review articles omitted in the present literature survey are mostly described by foreign authors: an effort to systemize the concerned fields might be required in this country. (K.T.)

  4. Spatial relationship between climatologies and changes in global vegetation activity.

    Science.gov (United States)

    de Jong, Rogier; Schaepman, Michael E; Furrer, Reinhard; de Bruin, Sytze; Verburg, Peter H

    2013-06-01

    Vegetation forms a main component of the terrestrial biosphere and plays a crucial role in land-cover and climate-related studies. Activity of vegetation systems is commonly quantified using remotely sensed vegetation indices (VI). Extensive reports on temporal trends over the past decades in time series of such indices can be found in literature. However, little remains known about the processes underlying these changes at large spatial scales. In this study, we aimed at quantifying the spatial relationship between changes in potential climatic growth constraints (i.e. temperature, precipitation and incident solar radiation) and changes in vegetation activity (1982-2008). We demonstrate an additive spatial model with 0.5° resolution, consisting of a regression component representing climate-associated effects and a spatially correlated field representing the combined influence of other factors, including land-use change. Little over 50% of the spatial variance could be attributed to changes in climatologies; conspicuously, many greening trends and browning hotspots in Argentina and Australia. The nonassociated model component may contain large-scale human interventions, feedback mechanisms or natural effects, which were not captured by the climatologies. Browning hotspots in this component were especially found in subequatorial Africa. On the scale of land-cover types, strongest relationships between climatologies and vegetation activity were found in forests, including indications for browning under warming conditions (analogous to the divergence issue discussed in dendroclimatology). © 2013 Blackwell Publishing Ltd.

  5. Study on temporal and spatial variations of urban land use based on land change data

    Science.gov (United States)

    Jiang, Ping; Liu, Yanfang; Fan, Min; Zhang, Yang

    2009-10-01

    With the rapid development of urbanization, demands of urban land increase in succession, hence, to analyze temporal and spatial variations of urban land use becomes more and more important. In this paper, the principle of trend surface analysis and formula of urban land sprawl index ( ULSI) are expatiated at first, and then based on land change data of Jiayu county, the author fits quadratic trend surface by choosing urban land area as dependent variable and urbanization and GDP as independent variables from 1996 to 2006, draws isoline of trend surface and residual values; and then urban land sprawl indexes of towns are calculated on the basis of urban land area of 1996 and 2006 and distribution map of ULSI is plotted. After analyzing those results, we can conclude that there is consanguineous relationship between urban land area and urbanization, economic level etc.

  6. Study of geographical trends of polycyclic aromatic hydrocarbons using pine needles

    Science.gov (United States)

    Amigo, José Manuel; Ratola, Nuno; Alves, Arminda

    2011-10-01

    In this work, pine needles were used as polycyclic aromatic hydrocarbons (PAHs) markers to study the PAHs distribution over several geographical locations in Portugal and over time. Four pine needle sampling campaigns (winter, spring, summer and autumn 2007) were carried out in 29 sites, covering the major urban centres, some industrial points, smaller cities, rural areas and remote locations. Needles from Pinus pinaster Ait. and Pinus pinea L. trees were collected from 2005 and 2006 shoots, corresponding to one up to three years of exposure. Spatial trends of the incidence of PAHs indicate an increase from the remote to the urban and industrial sites. The mean values for the sum of 16 PAHs ranged from 96 ± 30 ng g -1 (dry weight) for remote sites to 866 ± 304 ng g -1 (dw) for industrial sites for P. pinaster needles and from 188 ± 117 ng g -1 (dw) for rural sites to 337 ± 153 ng g -1 (dw) for urban sites for P. pinea. Geographic information system tools and principal component analysis revealed that the contamination patterns of PAHs are somehow related to several socio-geographic parameters of the sampling sites. The geographical trend for the PAHs is similar between seasons in terms of PAH levels, but some diverse behaviour is found on the separation of lighter and heavier PAHs. Differences between P. pinaster and P. pinea needles are stronger in terms of PAH uptake loads than in the site type fingerprints.

  7. Exploring the Mechanisms of Ecological Land Change Based on the Spatial Autoregressive Model: A Case Study of the Poyang Lake Eco-Economic Zone, China

    Directory of Open Access Journals (Sweden)

    Hualin Xie

    2013-12-01

    Full Text Available Ecological land is one of the key resources and conditions for the survival of humans because it can provide ecosystem services and is particularly important to public health and safety. It is extremely valuable for effective ecological management to explore the evolution mechanisms of ecological land. Based on spatial statistical analyses, we explored the spatial disparities and primary potential drivers of ecological land change in the Poyang Lake Eco-economic Zone of China. The results demonstrated that the global Moran’s I value is 0.1646 during the 1990 to 2005 time period and indicated significant positive spatial correlation (p < 0.05. The results also imply that the clustering trend of ecological land changes weakened in the study area. Some potential driving forces were identified by applying the spatial autoregressive model in this study. The results demonstrated that the higher economic development level and industrialization rate were the main drivers for the faster change of ecological land in the study area. This study also tested the superiority of the spatial autoregressive model to study the mechanisms of ecological land change by comparing it with the traditional linear regressive model.

  8. Spatial and Temporal Variability of Potential Evaporation across North American Forests

    Directory of Open Access Journals (Sweden)

    Robbie A. Hember

    2017-01-01

    Full Text Available Given the widespread ecological implications that would accompany any significant change in evaporative demand of the atmosphere, this study investigated spatial and temporal variation in several accepted expressions of potential evaporation (PE. The study focussed on forest regions of North America, with 1 km-resolution spatial coverage and a monthly time step, from 1951–2014. We considered Penman’s model (EPen, the Priestley–Taylor model (EPT, ‘reference’ rates based on the Penman–Monteith model for grasslands (ERG, and reference rates for forests that are moderately coupled (ERFu and well coupled (ERFc to the atmosphere. To give context to the models, we also considered a statistical fit (EPanFit to measurements of pan evaporation (EPan. We documented how each model compared with EPan, differences in attribution of variance in PE to specific driving factors, mean spatial patterns, and time trends from 1951–2014. The models did not agree strongly on the sensitivity to underlying drivers, zonal variation of PE, or on the magnitude of trends from 1951–2014. Sensitivity to vapour pressure deficit (Da differed among models, being absent from EPT and strongest in ERFc. Time trends in reference rates derived from the Penman–Monteith equation were highly sensitive to how aerodynamic conductance was set. To the extent that EPanFit accurately reflects the sensitivity of PE to Da over land surfaces, future trends in PE based on the Priestley–Taylor model may underestimate increasing evaporative demand, while reference rates for forests, that assume strong canopy-atmosphere coupling in the Penman–Monteith model, may overestimate increasing evaporative demand. The resulting historical database, covering the spectrum of different models of PE applied in modern studies, can serve to further investigate biosphere-hydroclimate relationships across North America.

  9. Exploration of Urban Spatial Planning Evaluation Based on Humanland Harmony

    Science.gov (United States)

    Hu, X. S.; Ma, Q. R.; Liang, W. Q.; Wang, C. X.; Xiong, X. Q.; Han, X. H.

    2017-09-01

    This study puts forward a new concept, "population urbanization level forecast - driving factor analysis - urban spatial planning analysis" for achieving efficient and intensive development of urbanization considering human-land harmony. We analyzed big data for national economic and social development, studied the development trends of population urbanization and its influencing factors using the grey system model in Chengmai county of Hainan province, China. In turn, we calculated the population of Chengmai coming years based on the forecasting urbanization rate and the corresponding amount of urban construction land, and evaluated the urban spatial planning with GIS spatial analysis method in the study area. The result shows that the proposed concept is feasible for evaluation of urban spatial planning, and is meaningful for guiding the rational distribution of urban space, controlling the scale of development, improving the quality of urbanization and thus promoting highly-efficient and intensive use of limited land resource.

  10. Development of Spatial Thinking in Process of Studying Stereometry

    Directory of Open Access Journals (Sweden)

    E I Sanina

    2013-12-01

    Full Text Available The article examines the development of spatial thinking while studying solid geometry. The key note of the study is to examine the selected levels of spatial thinking: the creation and manipulation of spatial images in the course of solving stereometric problems.

  11. Spatial analysis of precipitation time series over the Upper Indus Basin

    Science.gov (United States)

    Latif, Yasir; Yaoming, Ma; Yaseen, Muhammad

    2018-01-01

    The upper Indus basin (UIB) holds one of the most substantial river systems in the world, contributing roughly half of the available surface water in Pakistan. This water provides necessary support for agriculture, domestic consumption, and hydropower generation; all critical for a stable economy in Pakistan. This study has identified trends, analyzed variability, and assessed changes in both annual and seasonal precipitation during four time series, identified herein as: (first) 1961-2013, (second) 1971-2013, (third) 1981-2013, and (fourth) 1991-2013, over the UIB. This study investigated spatial characteristics of the precipitation time series over 15 weather stations and provides strong evidence of annual precipitation by determining significant trends at 6 stations (Astore, Chilas, Dir, Drosh, Gupis, and Kakul) out of the 15 studied stations, revealing a significant negative trend during the fourth time series. Our study also showed significantly increased precipitation at Bunji, Chitral, and Skardu, whereas such trends at the rest of the stations appear insignificant. Moreover, our study found that seasonal precipitation decreased at some locations (at a high level of significance), as well as periods of scarce precipitation during all four seasons. The observed decreases in precipitation appear stronger and more significant in autumn; having 10 stations exhibiting decreasing precipitation during the fourth time series, with respect to time and space. Furthermore, the observed decreases in precipitation appear robust and more significant for regions at high elevation (>1300 m). This analysis concludes that decreasing precipitation dominated the UIB, both temporally and spatially including in the higher areas.

  12. Mass fluxes and spatial trends of xenobiotics in the waters of the city of Halle, Germany

    International Nuclear Information System (INIS)

    Reinstorf, F.; Strauch, G.; Schirmer, K.; Glaeser, H.-R.; Moeder, M.; Wennrich, R.; Osenbrueck, K.; Schirmer, M.

    2008-01-01

    The behaviour and the effects of xenobiotics including pharmaceuticals and fragrances in the environment are widely unknown. In order to improve our knowledge, field investigations and modelling approaches for the entire area of the city of Halle/Saale, Germany, were performed. The distribution of the concentration values and mass fluxes are exemplified using indicators such as Bisphenol A, t-Nonylphenol, Carbamacepine, Galaxolide, Tonalide, Gadolinium and isotopes. Concentrations at a magnitude of ng/L to μg/L were found ubiquitously in the ground and surface waters. Using the concentration values, the impact of the city concerning the indicators was not always evident. Only the assessment of the mass fluxes shows significant urban impacts along the city passage. The calculation of the mass fluxes shows increasing values for all investigated xenobiotics during the city passage; only Bisphenol A stagnates. A balance model of water and indicator mass fluxes was built up for the entire city area. - Xenobiotics are ubiquitous in the investigated urban aquatic system and are quantified by a large scale mass balance to find spatial trends

  13. How does spatial study design influence density estimates from spatial capture-recapture models?

    Directory of Open Access Journals (Sweden)

    Rahel Sollmann

    Full Text Available When estimating population density from data collected on non-invasive detector arrays, recently developed spatial capture-recapture (SCR models present an advance over non-spatial models by accounting for individual movement. While these models should be more robust to changes in trapping designs, they have not been well tested. Here we investigate how the spatial arrangement and size of the trapping array influence parameter estimates for SCR models. We analysed black bear data collected with 123 hair snares with an SCR model accounting for differences in detection and movement between sexes and across the trapping occasions. To see how the size of the trap array and trap dispersion influence parameter estimates, we repeated analysis for data from subsets of traps: 50% chosen at random, 50% in the centre of the array and 20% in the South of the array. Additionally, we simulated and analysed data under a suite of trap designs and home range sizes. In the black bear study, we found that results were similar across trap arrays, except when only 20% of the array was used. Black bear density was approximately 10 individuals per 100 km(2. Our simulation study showed that SCR models performed well as long as the extent of the trap array was similar to or larger than the extent of individual movement during the study period, and movement was at least half the distance between traps. SCR models performed well across a range of spatial trap setups and animal movements. Contrary to non-spatial capture-recapture models, they do not require the trapping grid to cover an area several times the average home range of the studied species. This renders SCR models more appropriate for the study of wide-ranging mammals and more flexible to design studies targeting multiple species.

  14. Early Warning Signals of Ecological Transitions: Methods for Spatial Patterns

    Science.gov (United States)

    Brock, William A.; Carpenter, Stephen R.; Ellison, Aaron M.; Livina, Valerie N.; Seekell, David A.; Scheffer, Marten; van Nes, Egbert H.; Dakos, Vasilis

    2014-01-01

    A number of ecosystems can exhibit abrupt shifts between alternative stable states. Because of their important ecological and economic consequences, recent research has focused on devising early warning signals for anticipating such abrupt ecological transitions. In particular, theoretical studies show that changes in spatial characteristics of the system could provide early warnings of approaching transitions. However, the empirical validation of these indicators lag behind their theoretical developments. Here, we summarize a range of currently available spatial early warning signals, suggest potential null models to interpret their trends, and apply them to three simulated spatial data sets of systems undergoing an abrupt transition. In addition to providing a step-by-step methodology for applying these signals to spatial data sets, we propose a statistical toolbox that may be used to help detect approaching transitions in a wide range of spatial data. We hope that our methodology together with the computer codes will stimulate the application and testing of spatial early warning signals on real spatial data. PMID:24658137

  15. Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA Great Plains: Part I. Spatial trends

    Science.gov (United States)

    Kukal, M.; Irmak, S.

    2016-11-01

    Due to their substantial spatio-temporal behavior, long-term quantification and analyses of important hydrological variables are essential for practical applications in water resources planning, evaluating the water use of agricultural crop production and quantifying crop evapotranspiration patterns and irrigation management vs. hydrologic balance relationships. Observed data at over 800 sites across the Great Plains of USA, comprising of 9 states and 2,307,410 km2 of surface area, which is about 30% of the terrestrial area of the USA, were used to quantify and map large-scale and long-term (1968-2013) spatial trends of air temperatures, daily temperature range (DTR), precipitation, grass-reference evapotranspiration (ETo) and aridity index (AI) at monthly, growing season and annual time steps. Air temperatures had a strong north to south increasing trend, with annual average varying from -1 to 24 °C, and growing season average temperature varying from 8 to 30 °C. DTR gradually decreased from western to eastern parts of the region, with a regional annual and growing season averages of 14.25 °C and 14.79 °C, respectively. Precipitation had a gradual shift towards higher magnitudes from west to east, with the average annual and growing season (May-September) precipitation ranging from 163 to 1486 mm and from 98 to 746 mm, respectively. ETo had a southwest-northeast decreasing trend, with regional annual and growing season averages of 1297 mm and 823 mm, respectively. AI increased from west to east, indicating higher humidity (less arid) towards the east, with regional annual and growing season averages of 0.49 and 0.44, respectively. The spatial datasets and maps for these important climate variables can serve as valuable background for climate change and hydrologic studies in the Great Plains region. Through identification of priority areas from the developed maps, efforts of the concerned personnel and agencies and resources can be diverted towards development

  16. A global single-sensor analysis of 2002-2011 tropospheric nitrogen dioxide trends observed from space

    Science.gov (United States)

    Schneider, P.; van der A, R. J.

    2012-08-01

    A global nine-year archive of monthly tropospheric NO2 data acquired by the SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) instrument was analyzed with respect to trends between August 2002 and August 2011. In the past, similar studies relied on combining data from multiple sensors; however, the length of the SCIAMACHY data set now for the first time allows utilization of a consistent time series from just a single sensor for mapping NO2 trends at comparatively high horizontal resolution (0.25°). This study provides an updated analysis of global patterns in NO2 trends and finds that previously reported decreases in tropospheric NO2 over Europe and the United States as well as strong increases over China and several megacities in Asia have continued in recent years. Positive trends of up to 4.05 (±0.41) × 1015 molecules cm-2 yr-1 and up to 19.7 (±1.9) % yr-1 were found over China, with the regional mean trend being 7.3 (±3.1) % yr-1. The megacity with the most rapid relative increase was found to be Dhaka in Bangladesh. Subsequently focusing on Europe, the study further analyzes trends by country and finds significantly decreasing trends for seven countries ranging from -3.0 (±1.6) % yr-1 to -4.5 (±2.3) % yr-1. A comparison of the satellite data with station data indicates that the trends derived from both sources show substantial differences on the station scale, i.e., when comparing a station trend directly with the equivalent satellite-derived trend at the same location, but provide quite similar large-scale spatial patterns. Finally, the SCIAMACHY-derived NO2 trends are compared with equivalent trends in NO2concentration computed using the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP) model. The results show that the spatial patterns in trends computed from both data sources mostly agree in Central and Western Europe, whereas substantial differences

  17. The spatial comfort study of shophouse at Kampung Madras

    Science.gov (United States)

    Ginting, Y. U. U.; Ginting, N.; Zahrah, W.

    2018-03-01

    This Research comes from the increasing quantity of shophouse in downtown Medan and the suburban area. The condition of shophouse tend to have narrowly spaced rooms, the middle area of the house are poorly lighted, and lots of space left unused. This research is supported by many spatial issues from previous studies. This study is conducted to determine the level of comfort of shophouse as a function of living space and focused on the spatial aspect namely anthropometry, indoor space circulation, space requirement and function, spatial design and indoor visual. This study uses the descriptive method with the qualitative and quantitative approach. Data collection technique is done by field observation, questionnaire method is also used to get the respondent perception of the spatial comfort of a shophouse. The result indicates that the level of spatial comfort of the shophouse is an uncomfort. So the improvements in the circulation of access to the building, spatial design, lighting, and aeration are needed to improve the spatial comfort of a shophouse.

  18. Forecasting Temporal and Spatial Climatological Influence for Land Suitability Evaluation in Bentota Sri Lanka

    Directory of Open Access Journals (Sweden)

    Gayani Ranasinghe

    2017-01-01

    Full Text Available Climate change has raised much concern regarding its impacts on future land use planning, varying by region, time, and socio-economic development path. The principle purpose of land suitability evaluation is to predict the potential and limitation of the land for crop production and other land uses. This study was carried out to predict the temperature and rainfall trends as one of the major factor for evaluating land suitability. Climatic data such as monthly mean temperature, total monthly rainfall, maximum daily rainfall and total annual rainfall during last 30 years of all weather stations located in Bentota River basin was collected and analyzed applying time series analysis, correlation analysis and Manna Kendall trend test methods. Spatial distribution of forecast rainfall values was illustrated applying Arc GIS software. The findings revealed that monthly mean temperature and maximum daily rainfall had a general increasing trend whereas, total monthly rainfall and total annual rainfall showed a general decreasing trend in  Bentota area. It was indicated relatively high rainfall situations during May and October while low rainfall situations during January and February by occurring flood situation in once per five year. During Yala season the area will be received comparatively more rainfall (331mm than Maha season (300mm in future. Community and the farmers in this area can be aware about the anticipated spatial distribution of total monthly rainfall during two major seasons and flood occurrence periods. Decision makers should evaluate land suitability of Bentota area by considering above climatological influences and its spatial distribution pattern that identified as major outcome of this research. The approach and the methodology adopted in this study will be useful for other researchers, agriculturalist and planners to identify the future climatological influences and its spatial distribution pattern for land suitability evaluations

  19. An empirical study on the spatial distribution of the population, economy and water resources in Northeast China

    Science.gov (United States)

    Zhang, Conglin; Liu, Yu; Qiao, Haijuan

    The relationship among the population, economy and water resources is complex, and the contradictions and conflicts will appear and aggravate with the rapid development of economy and society in Northeast China. Based on the statistical analysis of the available data, this paper depicted the static distribution characteristics of the population, economy and water resources of Northeast China in 2011. It was found that the spatial distribution of the population, economy and water resources was unbalanced in Northeast China. The water resources mismatched with the population and economy. The population and economy were relatively dense and developed in the southwestern part of Northeast China respectively, while the water resources was relatively scarce. However, the situations in the northern part of Northeast China were opposite to those in the southwestern part. The population-economy inconsistence indexes of the cities in northern part of Northeast China showed a significant trend of spatial aggregation and heterogeneity. The cities with lower (1) inconsistence indexes all faced the problem of water resources shortage. Applying geometric gravity center method and grey correlation model, the result indicated that there was relatively high spatial relevance and the relative deviation among the spatial dynamic distributions of the population, economy and water resources was large. The gravity centers of economy and per capita average annual total water resources moved westward, while the gravity center of population gravity center moved eastward in the period of 1997-2011 in Northeast China. It must be noted that, the migration trend of the economy gravity center was more significant than those of the population and water resources.

  20. Mediterranean Ocean Colour Chlorophyll Trends.

    Science.gov (United States)

    Colella, Simone; Falcini, Federico; Rinaldi, Eleonora; Sammartino, Michela; Santoleri, Rosalia

    2016-01-01

    In being at the base of the marine food web, phytoplankton is particularly important for marine ecosystem functioning (e.g., biodiversity). Strong anthropization, over-exploitation of natural resources, and climate change affect the natural amount of phytoplankton and, therefore, represent a continuous threat to the biodiversity in marine waters. In particular, a concerning risks for coastal waters is the increase in nutrient inputs of terrestrial/anthropogenic origin that can lead to undesirable modifications of phytoplankton concentration (i.e., eutrophication). Monitoring chlorophyll (Chl) concentration, which is a proxy of phytoplankton biomass, is an efficient tool for recording and understanding the response of the marine ecosystem to human pressures and thus for detecting eutrophication. Here, we compute Chl trends over the Mediterranean Sea by using satellite data, also highlighting the fact that remote sensing may represent an efficient and reliable solution to synoptically control the "good environmental status" (i.e., the Marine Directive to achieve Good Environmental Status of EU marine waters by 2020) and to assess the application of international regulations and environmental directives. Our methodology includes the use of an ad hoc regional (i.e., Mediterranean) algorithm for Chl concentration retrieval, also accounting for the difference between offshore (i.e., Case I) and coastal (i.e., Case II) waters. We apply the Mann-Kendall test and the Sens's method for trend estimation to the Chl concentration de-seasonalized monthly time series, as obtained from the X-11 technique. We also provide a preliminary analysis of some particular trends by evaluating their associated inter-annual variability. The high spatial resolution of our approach allows a clear identification of intense trends in those coastal waters that are affected by river outflows. We do not attempt to attribute the observed trends to specific anthropogenic events. However, the trends

  1. Mediterranean Ocean Colour Chlorophyll Trends.

    Directory of Open Access Journals (Sweden)

    Simone Colella

    Full Text Available In being at the base of the marine food web, phytoplankton is particularly important for marine ecosystem functioning (e.g., biodiversity. Strong anthropization, over-exploitation of natural resources, and climate change affect the natural amount of phytoplankton and, therefore, represent a continuous threat to the biodiversity in marine waters. In particular, a concerning risks for coastal waters is the increase in nutrient inputs of terrestrial/anthropogenic origin that can lead to undesirable modifications of phytoplankton concentration (i.e., eutrophication. Monitoring chlorophyll (Chl concentration, which is a proxy of phytoplankton biomass, is an efficient tool for recording and understanding the response of the marine ecosystem to human pressures and thus for detecting eutrophication. Here, we compute Chl trends over the Mediterranean Sea by using satellite data, also highlighting the fact that remote sensing may represent an efficient and reliable solution to synoptically control the "good environmental status" (i.e., the Marine Directive to achieve Good Environmental Status of EU marine waters by 2020 and to assess the application of international regulations and environmental directives. Our methodology includes the use of an ad hoc regional (i.e., Mediterranean algorithm for Chl concentration retrieval, also accounting for the difference between offshore (i.e., Case I and coastal (i.e., Case II waters. We apply the Mann-Kendall test and the Sens's method for trend estimation to the Chl concentration de-seasonalized monthly time series, as obtained from the X-11 technique. We also provide a preliminary analysis of some particular trends by evaluating their associated inter-annual variability. The high spatial resolution of our approach allows a clear identification of intense trends in those coastal waters that are affected by river outflows. We do not attempt to attribute the observed trends to specific anthropogenic events. However

  2. A Comparison of Grizzly Bear Demographic Parameters Estimated from Non-Spatial and Spatial Open Population Capture-Recapture Models.

    Science.gov (United States)

    Whittington, Jesse; Sawaya, Michael A

    2015-01-01

    Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal's home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786-1.071) for females, 0.844 (0.703-0.975) for males, and 0.882 (0.779-0.981) for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758-1.024) for females, 0.825 (0.700-0.948) for males, and 0.863 (0.771-0.957) for both sexes. The combination of low densities, low reproductive rates, and predominantly negative population growth

  3. A Comparison of Grizzly Bear Demographic Parameters Estimated from Non-Spatial and Spatial Open Population Capture-Recapture Models.

    Directory of Open Access Journals (Sweden)

    Jesse Whittington

    Full Text Available Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal's home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786-1.071 for females, 0.844 (0.703-0.975 for males, and 0.882 (0.779-0.981 for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758-1.024 for females, 0.825 (0.700-0.948 for males, and 0.863 (0.771-0.957 for both sexes. The combination of low densities, low reproductive rates, and predominantly negative

  4. Temporal-spatial trends in heavy metal contents in sediment-derived soils along the Sea Scheldt river (Belgium)

    International Nuclear Information System (INIS)

    Vandecasteele, B.; Vos, B. de; Tack, F.M.G.

    2003-01-01

    The alluvial plain upstream in the Sea Scheldt was more affected by upland disposal of polluted sediments. - The aim of this study was to survey the alluvial plains of the Sea Scheldt river in Belgium for the presence of old sediment-derived soils, and to appraise the heavy metal contamination at these sites. Historically, sediments of periodical dredging operations have been disposed in the alluvial plain without concern for the potential presence of contaminants. Up to 96% of the areas that were affected by sediment disposal (ca. 120 ha) was found to be polluted by at least one of the metals Cd, Cr, Zn or Pb. Concentrations of Cd, Cr and Zn were, in 10% of the cases, higher than 14, 1400 and 2200 mg/kg DM, respectively. Based on the Flemish decree on soil sanitation, Cu and Ni concentrations were of less environmental concern on any site. The pollution in the Sea Scheldt alluvial plain nevertheless is lower than for the Upper Scheldt alluvial plain. The sediment-derived soils in the most upstream part near Ghent were used for disposal of sediments from dredging operations elsewhere. Metal concentrations were explored and both spatial and temporal trend were analysed. The pollution levels encountered warrant caution as most of the soils affected by historical dredged sediment disposal are currently in use for pasture

  5. Demographic Trends in Germany and their Economic Implications

    OpenAIRE

    Rembrandt Scholz; Carsten Schröder

    2012-01-01

    The present paper explores demographic trends in Germany, as well as the determinants of these trends, and the economic implications of these demographic changes for the country. A detailed spatial analysis reveals substantial differences in the speed and intensity of the processes of population aging and population decline across the German regions. The results indicate that these processes are particularly pronounced in the state of Mecklenburg Western-Pomerania. As a new contribution to th...

  6. Wet-bulb, dew point, and air temperature trends in Spain

    Science.gov (United States)

    Moratiel, R.; Soriano, B.; Centeno, A.; Spano, D.; Snyder, R. L.

    2017-10-01

    This study analyses trends of mean ( T m), maximum ( T x), minimum ( T n), dew point ( T d), and wet-bulb temperatures ( T w) on an annual, seasonal, and monthly time scale over Spain during the period 1981-2010. The main purpose was to determine how temperature and humidity changes are impacting on T w, which is probably a better measure of climate change than temperature alone. In this study, 43 weather stations were used to detect data trends using the nonparametric Mann-Kendall test and the Sen method to estimate the slope of trends. Significant linear trends observed for T m, T x, and T n versus year were 56, 58, and 47 % of the weather stations, respectively, with temperature ranges between 0.2 and 0.4 °C per decade. The months with bigger trends were April, May, June, and July with the highest trend for T x. The spatial behaviour of T d and T w was variable, with various locations showing trends from -0.6 to +0.3 °C per decade for T d and from -0.4 to +0.5 °C per decade for T w. Both T d and T w showed negative trends for July, August, September, November, and December. Comparing the trends versus time of each variable versus each of the other variables exhibited poor relationships, which means you cannot predict the trend of one variable from the trend of another variable. The trend of T x was not related to the trend of T n. The trends of T x, T m, and T n versus time were unrelated to the trends versus time of either T d or T w. The trend of T w showed a high coefficient of determination with the trend of T d with an annual value of R 2 = 0.86. Therefore, the T w trend is more related to changes in humidity than temperature.

  7. Mapping trends of large and medium size carnivores of conservation interest in Romania

    Directory of Open Access Journals (Sweden)

    Constantin Cazacu

    2014-07-01

    Full Text Available We analysed yearly estimates of population size data during 2001-2012 for five carnivores species of conservation interest (Ursus arctos, Canis lupus, Lynx lynx, Felis silvestris and Canis aureus. Population size estimations were done by the game management authorities and integrated by the competent authorities on the Ministry of Environment and Climate Change. Trends in data were detected using non-parametric Mann-Kendall test. This test was chosen considering the short length of data series and its usefulness for non-normal distributed data. The trend was tested at three spatial scales: game management units (n=1565, biogeographical region (n=5 and national. Trends depicted for each game management unit were plotted using ArcGIS, resulting species trend distribution maps. For the studied period increasing population trends were observed for Ursus arctos, Canis lupus, Canis aureus and Lynx lynx, while for Felis silvestris there was no trend recorded. Such an analysis in especially useful for conservation proposes, game management and reporting obligations under article 17 of the EC Habitat Directive, using population trend as a proxy for population dynamics. We conclude that the status of the five carnivore species is favourable during the study period.

  8. A study of spatial resolution in pollution exposure modelling

    Directory of Open Access Journals (Sweden)

    Gustafsson Susanna

    2007-06-01

    Full Text Available Abstract Background This study is part of several ongoing projects concerning epidemiological research into the effects on health of exposure to air pollutants in the region of Scania, southern Sweden. The aim is to investigate the optimal spatial resolution, with respect to temporal resolution, for a pollutant database of NOx-values which will be used mainly for epidemiological studies with durations of days, weeks or longer periods. The fact that a pollutant database has a fixed spatial resolution makes the choice critical for the future use of the database. Results The results from the study showed that the accuracy between the modelled concentrations of the reference grid with high spatial resolution (100 m, denoted the fine grid, and the coarser grids (200, 400, 800 and 1600 meters improved with increasing spatial resolution. When the pollutant values were aggregated in time (from hours to days and weeks the disagreement between the fine grid and the coarser grids were significantly reduced. The results also illustrate a considerable difference in optimal spatial resolution depending on the characteristic of the study area (rural or urban areas. To estimate the accuracy of the modelled values comparison were made with measured NOx values. The mean difference between the modelled and the measured value were 0.6 μg/m3 and the standard deviation 5.9 μg/m3 for the daily difference. Conclusion The choice of spatial resolution should not considerably deteriorate the accuracy of the modelled NOx values. Considering the comparison between modelled and measured values we estimate that an error due to coarse resolution greater than 1 μg/m3 is inadvisable if a time resolution of one day is used. Based on the study of different spatial resolutions we conclude that for urban areas a spatial resolution of 200–400 m is suitable; and for rural areas the spatial resolution could be coarser (about 1600 m. This implies that we should develop a pollutant

  9. Temporal and spatial variations of rainfall erosivity in Southern Taiwan

    Science.gov (United States)

    Lee, Ming-Hsi; Lin, Huan-Hsuan; Chu, Chun-Kuang

    2014-05-01

    Soil erosion models are essential in developing effective soil and water resource conservation strategies. Soil erosion is generally evaluated using the Universal Soil Loss Equation (USLE) with an appropriate regional scale description. Among factors in the USLE model, the rainfall erosivity index (R) provides one of the clearest indications of the effects of climate change. Accurate estimation of rainfall erosivity requires continuous rainfall data; however, such data rarely demonstrate good spatial and temporal coverage. The data set consisted of 9240 storm events for the period 1993 to 2011, monitored by 27 rainfall stations of the Central Weather Bureau (CWB) in southern Taiwan, was used to analyze the temporal-spatial variations of rainfall erosivity. The spatial distribution map was plotted based on rainfall erosivity by the Kriging interpolation method. Results indicated that rainfall erosivity is mainly concentrated in rainy season from June to November typically contributed 90% of the yearly R factor. The temporal variations of monthly rainfall erosivity during June to November and annual rainfall erosivity have increasing trend from 1993 to 2011. There is an increasing trend from southwest to northeast in spatial distribution of rainfall erosivity in southern Taiwan. The results further indicated that there is a higher relationship between elevation and rainfall erosivity. The method developed in this study may also be useful for sediment disasters on Climate Change.

  10. Exploring spatial-temporal dynamics of fire regime features in mainland Spain

    Science.gov (United States)

    Jiménez-Ruano, Adrián; Rodrigues Mimbrero, Marcos; de la Riva Fernández, Juan

    2017-10-01

    This paper explores spatial-temporal dynamics in fire regime features, such as fire frequency, burnt area, large fires and natural- and human-caused fires, as an essential part of fire regime characterization. Changes in fire features are analysed at different spatial - regional and provincial/NUTS3 - levels, together with summer and winter temporal scales, using historical fire data from Spain for the period 1974-2013. Temporal shifts in fire features are investigated by means of change point detection procedures - Pettitt test, AMOC (at most one change), PELT (pruned exact linear time) and BinSeg (binary segmentation) - at a regional level to identify changes in the time series of the features. A trend analysis was conducted using the Mann-Kendall and Sen's slope tests at both the regional and NUTS3 level. Finally, we applied a principal component analysis (PCA) and varimax rotation to trend outputs - mainly Sen's slope values - to summarize overall temporal behaviour and to explore potential links in the evolution of fire features. Our results suggest that most fire features show remarkable shifts between the late 1980s and the first half of the 1990s. Mann-Kendall outputs revealed negative trends in the Mediterranean region. Results from Sen's slope suggest high spatial and intra-annual variability across the study area. Fire activity related to human sources seems to be experiencing an overall decrease in the northwestern provinces, particularly pronounced during summer. Similarly, the Hinterland and the Mediterranean coast are gradually becoming less fire affected. Finally, PCA enabled trends to be synthesized into four main components: winter fire frequency (PC1), summer burnt area (PC2), large fires (PC3) and natural fires (PC4).

  11. Interrupted time-series analysis: studying trends in neurosurgery.

    Science.gov (United States)

    Wong, Ricky H; Smieliauskas, Fabrice; Pan, I-Wen; Lam, Sandi K

    2015-12-01

    OBJECT Neurosurgery studies traditionally have evaluated the effects of interventions on health care outcomes by studying overall changes in measured outcomes over time. Yet, this type of linear analysis is limited due to lack of consideration of the trend's effects both pre- and postintervention and the potential for confounding influences. The aim of this study was to illustrate interrupted time-series analysis (ITSA) as applied to an example in the neurosurgical literature and highlight ITSA's potential for future applications. METHODS The methods used in previous neurosurgical studies were analyzed and then compared with the methodology of ITSA. RESULTS The ITSA method was identified in the neurosurgical literature as an important technique for isolating the effect of an intervention (such as a policy change or a quality and safety initiative) on a health outcome independent of other factors driving trends in the outcome. The authors determined that ITSA allows for analysis of the intervention's immediate impact on outcome level and on subsequent trends and enables a more careful measure of the causal effects of interventions on health care outcomes. CONCLUSIONS ITSA represents a significant improvement over traditional observational study designs in quantifying the impact of an intervention. ITSA is a useful statistical procedure to understand, consider, and implement as the field of neurosurgery evolves in sophistication in big-data analytics, economics, and health services research.

  12. Denitrification potential of riparian soils in relation to multiscale spatial environmental factors: a case study of a typical watershed, China.

    Science.gov (United States)

    Wei, Jianbing; Feng, Hao; Cheng, Quanguo; Gao, Shiqian; Liu, Haiyan

    2017-02-01

    The objective of this study was to test the hypothesis that environmental regulators of riparian zone soil denitrification potential differ according to spatial scale within a watershed; consequently, a second objective was to provide spatial strategies for conserving and restoring the purification function of runoff in riparian ecosystems. The results show that soil denitrification in riparian zones was more heterogeneous at the profile scale than at the cross-section and landscape scales. At the profile scale, biogeochemical factors (including soil total organic carbon, total nitrogen, and nitrate-nitrogen) were the major direct regulators of the spatial distribution of soil denitrification enzyme activity (DEA). At the cross-section scale, factors included distance from river bank and vegetation density, while landscape-scale factors, including topographic index, elevation, and land use types, indirectly regulated the spatial distribution of DEA. At the profile scale, soil DEA was greatest in the upper soil layers. At the cross-section scale, maximum soil DEA occurred in the mid-part of the riparian zone. At the landscape scale, soil DEA showed an increasing trend towards downstream sites, except for those in urbanized areas.

  13. Trends and Variability in Temperature Sensitivity of Lilac Flowering Phenology

    Science.gov (United States)

    Wang, Huanjiong; Dai, Junhu; Rutishauser, This; Gonsamo, Alemu; Wu, Chaoyang; Ge, Quansheng

    2018-03-01

    The responses of plant phenology to temperature variability have many consequences for ecological processes, agriculture, forestry, and human health. Temperature sensitivity (ST) of phenology could measure how and to what degree plant could phenologically track climate change. The long-term trends and spatial patterns in ST have been well studied for vegetative phenology such as leaf unfolding, but trends to be expected for reproductive phenology in the future remain unknown. Here we investigate trends and factors driving the temporal variation of ST of first bloom date (FBD). Using the long-term FBD records during 1963-2013 for common lilac (Syringa vulgaris) from 613 stations in Europe, we compared changes in ST from the beginning to the end of the study period. The Spearman partial correlations were used to assess the importance of four influencing factors. The results showed that the temporal changes in ST of FBD varied considerably among time scales. Mean ST decreased significantly by 0.92 days °C-1 from 1963-1972 to 2004-2013 (P plant species in other climates and environments using similar methods to our study.

  14. Examining Spatiotemporal Urbanization Patterns in Kathmandu Valley, Nepal: Remote Sensing and Spatial Metrics Approaches

    Directory of Open Access Journals (Sweden)

    Rajesh Bahadur Thapa

    2009-09-01

    Full Text Available This paper examines the spatiotemporal pattern of urbanization in Kathmandu Valley using remote sensing and spatial metrics techniques. The study is based on 33-years of time series data compiled from satellite images. Along with new developments within the city fringes and rural villages in the valley, shifts in the natural environment and newly developed socioeconomic strains between residents are emerging. A highly dynamic spatial pattern of urbanization is observed in the valley. Urban built-up areas had a slow trend of growth in the 1960s and 1970s but have grown rapidly since the 1980s. The urbanization process has developed fragmented and heterogeneous land use combinations in the valley. However, the refill type of development process in the city core and immediate fringe areas has shown a decreasing trend in the neighborhood distances between land use patches, and an increasing trend towards physical connectedness, which indicates a higher probability of homogenous landscape development in the upcoming decades.

  15. Evaluating the consistency of the 1982-1999 NDVI trends in the Iberian Peninsula across four time-series derived from the AVHRR sensor: LTDR, GIMMS, FASIR, and PAL-II.

    Science.gov (United States)

    Alcaraz-Segura, Domingo; Liras, Elisa; Tabik, Siham; Paruelo, José; Cabello, Javier

    2010-01-01

    Successive efforts have processed the Advanced Very High Resolution Radiometer (AVHRR) sensor archive to produce Normalized Difference Vegetation Index (NDVI) datasets (i.e., PAL, FASIR, GIMMS, and LTDR) under different corrections and processing schemes. Since NDVI datasets are used to evaluate carbon gains, differences among them may affect nations' carbon budgets in meeting international targets (such as the Kyoto Protocol). This study addresses the consistency across AVHRR NDVI datasets in the Iberian Peninsula (Spain and Portugal) by evaluating whether their 1982-1999 NDVI trends show similar spatial patterns. Significant trends were calculated with the seasonal Mann-Kendall trend test and their spatial consistency with partial Mantel tests. Over 23% of the Peninsula (N, E, and central mountain ranges) showed positive and significant NDVI trends across the four datasets and an additional 18% across three datasets. In 20% of Iberia (SW quadrant), the four datasets exhibited an absence of significant trends and an additional 22% across three datasets. Significant NDVI decreases were scarce (croplands in the Guadalquivir and Segura basins, La Mancha plains, and Valencia). Spatial consistency of significant trends across at least three datasets was observed in 83% of the Peninsula, but it decreased to 47% when comparing across the four datasets. FASIR, PAL, and LTDR were the most spatially similar datasets, while GIMMS was the most different. The different performance of each AVHRR dataset to detect significant NDVI trends (e.g., LTDR detected greater significant trends (both positive and negative) and in 32% more pixels than GIMMS) has great implications to evaluate carbon budgets. The lack of spatial consistency across NDVI datasets derived from the same AVHRR sensor archive, makes it advisable to evaluate carbon gains trends using several satellite datasets and, whether possible, independent/additional data sources to contrast.

  16. Regional Trends in Electromobility - Regional Study North America

    OpenAIRE

    Turrentine, Tom; Garas, Dhalia

    2015-01-01

    The subproject “Regional Trends in Electro mobility” aims at identifying and analyzing major trends in the field of electro mobility. The trend analysis will monitor research effort and upcoming technologies, policies, products and market developments in different focus regions around the world continuously to enable a systematic analysis of global trends. The regional trend analysis for electro mobility is a major keystone for the project success and therefore cooperation with...

  17. Characterizing permafrost active layer dynamics and sensitivity to landscape spatial heterogeneity in Alaska

    Science.gov (United States)

    Yi, Yonghong; Kimball, John S.; Chen, Richard H.; Moghaddam, Mahta; Reichle, Rolf H.; Mishra, Umakant; Zona, Donatella; Oechel, Walter C.

    2018-01-01

    An important feature of the Arctic is large spatial heterogeneity in active layer conditions, which is generally poorly represented by global models and can lead to large uncertainties in predicting regional ecosystem responses and climate feedbacks. In this study, we developed a spatially integrated modeling and analysis framework combining field observations, local-scale ( ˜ 50 m resolution) active layer thickness (ALT) and soil moisture maps derived from low-frequency (L + P-band) airborne radar measurements, and global satellite environmental observations to investigate the ALT sensitivity to recent climate trends and landscape heterogeneity in Alaska. Modeled ALT results show good correspondence with in situ measurements in higher-permafrost-probability (PP ≥ 70 %) areas (n = 33; R = 0.60; mean bias = 1.58 cm; RMSE = 20.32 cm), but with larger uncertainty in sporadic and discontinuous permafrost areas. The model results also reveal widespread ALT deepening since 2001, with smaller ALT increases in northern Alaska (mean trend = 0.32±1.18 cm yr-1) and much larger increases (> 3 cm yr-1) across interior and southern Alaska. The positive ALT trend coincides with regional warming and a longer snow-free season (R = 0.60 ± 0.32). A spatially integrated analysis of the radar retrievals and model sensitivity simulations demonstrated that uncertainty in the spatial and vertical distribution of soil organic carbon (SOC) was the largest factor affecting modeled ALT accuracy, while soil moisture played a secondary role. Potential improvements in characterizing SOC heterogeneity, including better spatial sampling of soil conditions and advances in remote sensing of SOC and soil moisture, will enable more accurate predictions of active layer conditions and refinement of the modeling framework across a larger domain.

  18. Brominated flame retardants in mangrove sediments of the Pearl River Estuary, South China: spatial distribution, temporal trend and mass inventory.

    Science.gov (United States)

    Zhang, Zai-Wang; Sun, Yu-Xin; Sun, Kai-Feng; Xu, Xiang-Rong; Yu, Shen; Zheng, Tian-Ling; Luo, Xiao-Jun; Tian, Yun; Hu, Yong-Xia; Diao, Zeng-Hui; Mai, Bi-Xian

    2015-03-01

    Sediments were collected from three mangrove wetlands in the Pearl River Estuary (PRE) of South China to investigate spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE). Concentrations of ΣPBDEs, DBDPE and BTBPE in mangrove sediments of the PRE ranged from 1.25-206, 0.364-34.9, and not detected-0.794 ng g(-1) dry weight, respectively. The highest concentrations of ΣPBDEs, DBDPE and BTBPE were found at the mangrove wetland from Shenzhen, followed by Zhuhai and Guangzhou, showing the dependence on the proximity to urban areas. PBDEs were the predominant brominated flame retardants (BFRs) in mangrove sediments. The concentrations of ΣPBDEs, DBDPE and BTBPE in sediment cores showed an increasing trend from the bottom to top layers, reflecting the increasing usage of these BFRs. The inventories of ΣPBDEs, DBDPE and BTBPE in mangrove sediments were 1962, 245, and 4.10 ng cm(-2), respectively. This is the first study to report the occurrence of DBDPE and BTBPE in mangrove ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Greater sage-grouse population trends across Wyoming

    Science.gov (United States)

    Edmunds, David; Aldridge, Cameron L.; O'Donnell, Michael; Monroe, Adrian

    2018-01-01

    The scale at which analyses are performed can have an effect on model results and often one scale does not accurately describe the ecological phenomena of interest (e.g., population trends) for wide-ranging species: yet, most ecological studies are performed at a single, arbitrary scale. To best determine local and regional trends for greater sage-grouse (Centrocercus urophasianus) in Wyoming, USA, we modeled density-independent and -dependent population growth across multiple spatial scales relevant to management and conservation (Core Areas [habitat encompassing approximately 83% of the sage-grouse population on ∼24% of surface area in Wyoming], local Working Groups [7 regional areas for which groups of local experts are tasked with implementing Wyoming's statewide sage-grouse conservation plan at the local level], Core Area status (Core Area vs. Non-Core Area) by Working Groups, and Core Areas by Working Groups). Our goal was to determine the influence of fine-scale population trends (Core Areas) on larger-scale populations (Working Group Areas). We modeled the natural log of change in population size ( peak M lek counts) by time to calculate the finite rate of population growth (λ) for each population of interest from 1993 to 2015. We found that in general when Core Area status (Core Area vs. Non-Core Area) was investigated by Working Group Area, the 2 populations trended similarly and agreed with the overall trend of the Working Group Area. However, at the finer scale where Core Areas were analyzed separately, Core Areas within the same Working Group Area often trended differently and a few large Core Areas could influence the overall Working Group Area trend and mask trends occurring in smaller Core Areas. Relatively close fine-scale populations of sage-grouse can trend differently, indicating that large-scale trends may not accurately depict what is occurring across the landscape (e.g., local effects of gas and oil fields may be masked by increasing

  20. Spatio-temporal trends in monthly pan evaporation in Aguascalientes, Mexico

    Science.gov (United States)

    Ruiz-Alvarez, Osias; Singh, Vijay P.; Medina, Juan Enciso; Munster, Clyde; Kaiser, Ronald; Ontiveros-Capurata, Ronald Ernesto; Diaz-Garcia, Luis Antonio; dos Santos, Carlos Antonio Costa

    2018-05-01

    Emission of greenhouse gases is being alleged to be causing climate change in different regions of the world. The objective of this study was to analyze the spatio-temporal trends of monthly evaporation at 52 weather stations in the state of Aguascalientes (Mexico) which have hydrometeorological records of long periods. The autocorrelation was eliminated with an auto-regressive model, and the trend was determined using the Spearman (S) and Kendall (K) tests. The statistical significance of the trend was determined with the Spearman correlation coefficient (r s) and the Z statistic (the test statistic of the normal distribution) both indicated that that there were statistically significant trends in 107 time series, of these 88 series had negative trends and 19 series had positive trends. Negative trends were present in all months of the year, while positive trends occurred from February to May and from October to December only. The reduction of evaporation from - 4.10 to - 20.50 mm/month/year from June to September showed a hopeful future scenario for rainfed agriculture. Irrigated agriculture during dry months could have a reduction of irrigation requirements as a consequence of the reduction in reference and crop evapotranspiration. The evaporation increase during dry months could increase irrigation requirements and pumping, mainly in March, April, and November when there are trends with increases of about 26.90, 24.60, and 23.90 mm/month/year, respectively. The spatial variability of evaporation trend means that other effects of climate change could vary in different parts of the state. Results of this study will be useful for farmers and institutions in charge of the administration of water resources for developing adaptation and mitigation strategies to climate change.

  1. Trends in Middle East climate extreme indices from 1950 to 2003

    Science.gov (United States)

    Zhang, Xuebin; Aguilar, Enric; Sensoy, Serhat; Melkonyan, Hamlet; Tagiyeva, Umayra; Ahmed, Nader; Kutaladze, Nato; Rahimzadeh, Fatemeh; Taghipour, Afsaneh; Hantosh, T. H.; Albert, Pinhas; Semawi, Mohammed; Karam Ali, Mohammad; Said Al-Shabibi, Mansoor Halal; Al-Oulan, Zaid; Zatari, Taha; Al Dean Khelet, Imad; Hamoud, Saleh; Sagir, Ramazan; Demircan, Mesut; Eken, Mehmet; Adiguzel, Mustafa; Alexander, Lisa; Peterson, Thomas C.; Wallis, Trevor

    2005-11-01

    A climate change workshop for the Middle East brought together scientists and data for the region to produce the first area-wide analysis of climate extremes for the region. This paper reports trends in extreme precipitation and temperature indices that were computed during the workshop and additional indices data that became available after the workshop. Trends in these indices were examined for 1950-2003 at 52 stations covering 15 countries, including Armenia, Azerbaijan, Bahrain, Cyprus, Georgia, Iran, Iraq, Israel, Jordan, Kuwait, Oman, Qatar, Saudi Arabia, Syria, and Turkey. Results indicate that there have been statistically significant, spatially coherent trends in temperature indices that are related to temperature increases in the region. Significant, increasing trends have been found in the annual maximum of daily maximum and minimum temperature, the annual minimum of daily maximum and minimum temperature, the number of summer nights, and the number of days where daily temperature has exceeded its 90th percentile. Significant negative trends have been found in the number of days when daily temperature is below its 10th percentile and daily temperature range. Trends in precipitation indices, including the number of days with precipitation, the average precipitation intensity, and maximum daily precipitation events, are weak in general and do not show spatial coherence. The workshop attendees have generously made the indices data available for the international research community.

  2. Evaluating the Consistency of the 1982–1999 NDVI Trends in the Iberian Peninsula across Four Time-series Derived from the AVHRR Sensor: LTDR, GIMMS, FASIR, and PAL-II

    Science.gov (United States)

    Alcaraz-Segura, Domingo; Liras, Elisa; Tabik, Siham; Paruelo, José; Cabello, Javier

    2010-01-01

    Successive efforts have processed the Advanced Very High Resolution Radiometer (AVHRR) sensor archive to produce Normalized Difference Vegetation Index (NDVI) datasets (i.e., PAL, FASIR, GIMMS, and LTDR) under different corrections and processing schemes. Since NDVI datasets are used to evaluate carbon gains, differences among them may affect nations’ carbon budgets in meeting international targets (such as the Kyoto Protocol). This study addresses the consistency across AVHRR NDVI datasets in the Iberian Peninsula (Spain and Portugal) by evaluating whether their 1982–1999 NDVI trends show similar spatial patterns. Significant trends were calculated with the seasonal Mann-Kendall trend test and their spatial consistency with partial Mantel tests. Over 23% of the Peninsula (N, E, and central mountain ranges) showed positive and significant NDVI trends across the four datasets and an additional 18% across three datasets. In 20% of Iberia (SW quadrant), the four datasets exhibited an absence of significant trends and an additional 22% across three datasets. Significant NDVI decreases were scarce (croplands in the Guadalquivir and Segura basins, La Mancha plains, and Valencia). Spatial consistency of significant trends across at least three datasets was observed in 83% of the Peninsula, but it decreased to 47% when comparing across the four datasets. FASIR, PAL, and LTDR were the most spatially similar datasets, while GIMMS was the most different. The different performance of each AVHRR dataset to detect significant NDVI trends (e.g., LTDR detected greater significant trends (both positive and negative) and in 32% more pixels than GIMMS) has great implications to evaluate carbon budgets. The lack of spatial consistency across NDVI datasets derived from the same AVHRR sensor archive, makes it advisable to evaluate carbon gains trends using several satellite datasets and, whether possible, independent/additional data sources to contrast. PMID:22205868

  3. Explaining the evaporation paradox in Jiangxi Province of China: Spatial distribution and temporal trends in potential evapotranspiration of Jiangxi Province from 1961 to 2013

    Directory of Open Access Journals (Sweden)

    Xianghui Lu

    2016-03-01

    Full Text Available Evaporation acts as an important component and a key control factor in land hydrological processes. In order to analyze the trend of change on potential evapotranspiration from 1961 to 2013 and to discuss the existence of the evaporation paradox in Jiangxi province, China, monthly meteorological data spanning the years 1961–2013 were analyzed in this study, where the data were collected from 15 national meteorological stations in Jiangxi Province. The Penman–Monteith equation was employed to compute the potential evapotranspiration (ET0. Spatial interpolation and data mining technology were used to analyze the spatial and temporal changes of ET0 and air temperature, with the effort to explain the evaporation paradox. By solving the total differential and the partial derivatives coefficients of the independent variables in Penman–Monteith equation, the cause of the paradox was quantitatively evaluated. The results showed that the annual ET0 had been decreasing significantly in Jiangxi Province since 1979, whereas the air temperature had been rising significantly, presenting the evaporation paradox. The decreases in sunshine duration and wind speed reduced ET0 by 0.207 mm and 0.060 mm, respectively, accounting for 92.3% and 26.7% of the total ET0, respectively. It is concluded that sunshine duration and wind speed are the main causes to the decrease in potential evapotranspiration in Jiangxi Province.

  4. Vehicle emission trends and spatial distribution in Shandong province, China, from 2000 to 2014

    Science.gov (United States)

    Sun, Shida; Jiang, Wei; Gao, Weidong

    2016-12-01

    Vehicle emissions have become a major source of air pollution in Shandong province, which has experienced a sharp growth of vehicle numbers in recent years and now has the largest vehicle population in China. This paper combines the COPERT IV model with the vehicle age distribution to estimate the temporal trends and map the spatial distributions of vehicle emissions in Shandong province during the period ranging from 2000 to 2014. Both conventional air pollutants and greenhouse gases are included. In addition, a high-resolution vehicle emission inventory at the prefecture level is developed and mapped on a 0.05° × 0.05° grid based on road information. Our results show that the emissions of all of the conventional air pollutants have decreased to various extents over the recent past, but greenhouse gas emissions have continued to increase due to the lack of effective control strategies. The total emissions of CO, NMVOC, NOX, PM10, CO2, CH4 and N2O from the Shandong vehicle fleet changed from 1734.5 Gg, 277.9 Gg, 177.0 Gg, 12.4 Gg, 19239.7 Gg, 11.3 Gg and 0.6 Gg, respectively, in 2000 to 1723.3 Gg, 234.2 Gg, 513.8 Gg, 29.5 Gg, 138,419.5 Gg, 15.3 Gg and 3.9 Gg, respectively, in 2014. Vehicle emissions were mainly concentrated in cities and became more dispersed in Shandong province between 2000 and 2014.

  5. Spatial and Temporal Trends in Global Emissions of Nitrogen Oxides from 1960 to 2014.

    Science.gov (United States)

    Huang, Tianbo; Zhu, Xi; Zhong, Qirui; Yun, Xiao; Meng, Wenjun; Li, Bengang; Ma, Jianmin; Zeng, Eddy Y; Tao, Shu

    2017-07-18

    The quantification of nitrogen oxide (NO x ) emissions is critical for air quality modeling. Based on updated fuel consumption and emission factor databases, a global emission inventory was compiled with high spatial (0.1° × 0.1°), temporal (monthly), and source (87 sources) resolutions for the period 1960 to 2014. The monthly emission data have been uploaded online ( http://inventory.pku.edu.cn ), along with a number of other air pollutant and greenhouse gas data for free download. Differences in source profiles, not global total quantities, between our results and those reported previously were found. There were significant differences in total and per capita emissions and emission intensities among countries, especially between the developing and developed countries. Globally, the total annual NO x emissions finally stopped increasing in 2013 after continuously increasing over several decades, largely due to strict control measures taken in China in recent years. Nevertheless, the peak year of NO x emissions was later than for many other major air pollutants. Per capita emissions, either among countries or over years, follow typical inverted U-shaped environmental Kuznets curves, indicating that the emissions increased during the early stage of development and were restrained when socioeconomic development reached certain points. Although the trends are similar among countries, the turning points of developing countries appeared sooner than those of developed countries in terms of development status, confirming late-move advantages.

  6. Groundwater-quality data in 12 GAMA study units: Results from the 2006–10 initial sampling period and the 2008–13 trend sampling period, California GAMA Priority Basin Project

    Science.gov (United States)

    Mathany, Timothy M.

    2017-03-09

    The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey in cooperation with the California State Water Resources Control Board. From 2004 through 2012, the GAMA-PBP collected samples and assessed the quality of groundwater resources that supply public drinking water in 35 study units across the State. Selected sites in each study unit were sampled again approximately 3 years after initial sampling as part of an assessment of temporal trends in water quality by the GAMA-PBP. Twelve of the study units, initially sampled during 2006–11 (initial sampling period) and sampled a second time during 2008–13 (trend sampling period) to assess temporal trends, are the subject of this report.The initial sampling was designed to provide a spatially unbiased assessment of the quality of untreated groundwater used for public water supplies in the 12 study units. In these study units, 550 sampling sites were selected by using a spatially distributed, randomized, grid-based method to provide spatially unbiased representation of the areas assessed (grid sites, also called “status sites”). After the initial sampling period, 76 of the previously sampled status sites (approximately 10 percent in each study unit) were randomly selected for trend sampling (“trend sites”). The 12 study units sampled both during the initial sampling and during the trend sampling period were distributed among 6 hydrogeologic provinces: Coastal (Northern and Southern), Transverse Ranges and Selected Peninsular Ranges, Klamath, Modoc Plateau and Cascades, and Sierra Nevada Hydrogeologic Provinces. For the purposes of this trend report, the six hydrogeologic provinces were grouped into two hydrogeologic regions based on location: Coastal and Mountain.The groundwater samples were analyzed for a number of synthetic organic

  7. Overcoming trends in irregularly spaced locations by regional polish - exemplified by estimation of the range of influence between Salmonella Dublin-seropositive cattle herds

    DEFF Research Database (Denmark)

    Ersbøll, Annette Kjær; Ersbøll, Bjarne Kjær

    2010-01-01

    The aim of the study was to develop a procedure to remove spatial trends in irregularly spaced data, with trends partly due to regional differences. Median polish is often used on regularly spaced (lattice) data where column and row medians are removed. For irregularly spaced data a low-resolutio...

  8. A full Bayes before-after study accounting for temporal and spatial effects: Evaluating the safety impact of new signal installations.

    Science.gov (United States)

    Sacchi, Emanuele; Sayed, Tarek; El-Basyouny, Karim

    2016-09-01

    Recently, important advances in road safety statistics have been brought about by methods able to address issues other than the choice of the best error structure for modeling crash data. In particular, accounting for spatial and temporal interdependence, i.e., the notion that the collision occurrence of a site or unit times depend on those of others, has become an important issue that needs further research. Overall, autoregressive models can be used for this purpose as they can specify that the output variable depends on its own previous values and on a stochastic term. Spatial effects have been investigated and applied mostly in the context of developing safety performance functions (SPFs) to relate crash occurrence to highway characteristics. Hence, there is a need for studies that attempt to estimate the effectiveness of safety countermeasures by including the spatial interdependence of road sites within the context of an observational before-after (BA) study. Moreover, the combination of temporal dynamics and spatial effects on crash frequency has not been explored in depth for SPF development. Therefore, the main goal of this research was to carry out a BA study accounting for spatial effects and temporal dynamics in evaluating the effectiveness of a road safety treatment. The countermeasure analyzed was the installation of traffic signals at unsignalized urban/suburban intersections in British Columbia (Canada). The full Bayes approach was selected as the statistical framework to develop the models. The results demonstrated that zone variation was a major component of total crash variability and that spatial effects were alleviated by clustering intersections together. Finally, the methodology used also allowed estimation of the treatment's effectiveness in the form of crash modification factors and functions with time trends. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Automated simulation and study of spatial-structural design processes

    NARCIS (Netherlands)

    Davila Delgado, J.M.; Hofmeyer, H.; Stouffs, R.; Sariyildiz, S.

    2013-01-01

    A so-called "Design Process Investigation toolbox" (DPI toolbox), has been developed. It is a set of computational tools that simulate spatial-structural design processes. Its objectives are to study spatial-structural design processes and to support the involved actors. Two case-studies are

  10. Exploratory Temporal and Spatial Analysis of Myocardial Infarction Hospitalizations in Calgary, Canada

    Directory of Open Access Journals (Sweden)

    Xiaoxiao Liu

    2017-12-01

    Full Text Available Spatial and temporal analyses are critical to understand the pattern of myocardial infarction (MI hospitalizations over space and time, and to identify their underlying determinants. In this paper, we analyze MI hospitalizations in Calgary from 2004 to 2013, stratified by age and gender. First, a seasonal trend decomposition analyzes the seasonality; then a linear regression models the trend component. Moran’s I and hot spot analyses explore the spatial pattern. Though exploratory, results show that most age and gender groups feature a statistically significant decline over the 10 years, consistent with previous studies in Canada. Decline rates vary across ages and genders, with the slowest decline observed for younger males. Each gender exhibits a seasonal pattern with peaks in both winter and summer. Spatially, MI hot spots are identified in older communities, and in socioeconomically and environmentally disadvantaged communities. In the older communities, higher MI rates appear to be more highly associated with demographics. Conversely, worse air quality appears to be locally associated with higher MI incidence in younger age groups. The study helps identify areas of concern, where MI hot spots are identified for younger age groups, suggesting the need for localized public health policies to target local risk factors.

  11. Heat Energy Markets: Trends of Spatial Organization

    Directory of Open Access Journals (Sweden)

    Olga Valeryevna Dyomina

    2016-12-01

    Full Text Available The author reviews competing forms of heat supply. It is shown that in Finland, Denmark, China and Russia the dominant form of heat supply is district heating system; in the United States and Canada the dominant form of heat supply is individual one. Using the countries’ data the author allocates 4 models of heat energy markets. The analysis is based on combinations of the following characteristics: the type of market, the orientation of market, the stage of market development, forms of state support of district heating systems and the approach to pricing. The results identified the failure of the current model of heat energy market in Russia (noncompetitive, manufacturer-oriented and evolved market with massive state support of its district heating system. The ‘target’ model of heat energy market in Russia is a model of noncompetitive, customer-oriented and evolved market with no state support of its district heating system. However, the ‘target’ model takes into account spatial heterogeneity of local heat energy markets in Russia only technically

  12. Analysis of temporal and spatial trends of hydro-climatic variables in the Wei River Basin.

    Science.gov (United States)

    Zhao, Jing; Huang, Qiang; Chang, Jianxia; Liu, Dengfeng; Huang, Shengzhi; Shi, Xiaoyu

    2015-05-01

    The Wei River is the largest tributary of the Yellow River in China. The relationship between runoff and precipitation in the Wei River Basin has been changed due to the changing climate and increasingly intensified human activities. In this paper, we determine abrupt changes in hydro-climatic variables and identify the main driving factors for the changes in the Wei River Basin. The nature of the changes is analysed based on data collected at twenty-one weather stations and five hydrological stations in the period of 1960-2010. The sequential Mann-Kendall test analysis is used to capture temporal trends and abrupt changes in the five sub-catchments of the Wei River Basin. A non-parametric trend test at the basin scale for annual data shows a decreasing trend of precipitation and runoff over the past fifty-one years. The temperature exhibits an increase trend in the entire period. The potential evaporation was calculated based on the Penman-Monteith equation, presenting an increasing trend of evaporation since 1990. The stations with a significant decreasing trend in annual runoff mainly are located in the west of the Wei River primarily interfered by human activities. Regression analysis indicates that human activity was possibly the main cause of the decline of runoff after 1970. Copyright © 2015. Published by Elsevier Inc.

  13. North Atlantic cyclones; trends, impacts and links to large-scale variability

    Science.gov (United States)

    Trigo, R. M.; Trigo, I. F.; Ramos, A. M.; Paredes, D.; Garcia-Herrera, R.; Liberato, M. L. R.; Valente, M. A.

    2009-04-01

    Based on the cyclone detection and tracking algorithm previously developed (Trigo, 2006) we have assessed the inter-annual variability and cyclone frequency trends between 1960 and 2000 for the Euro-Atlantic sector using the highest spatial resolution available (1.125° x 1.125°) from the ERA-40 Surface Level Pressure. Additionally, trends for the u and v wind speed components are also computed at the monthly and seasonal scales, using the same dataset. All cyclone and wind speed trend maps were computed with the corresponding statistical significance field. Results reveal a significant frequency decrease (increase) in the western Mediterranean (Greenland and Scandinavia), particularly in December, February and March. Seasonal and monthly analysis of wind speed trends shows similar spatial patterns. We show that these changes in the frequency of low pressure centers and the associated wind patterns are partially responsible for trends of the significant height of waves. Throughout the extended winter months (ONDJFM), regions with positive (negative) wind magnitude trends, of up to 5 cm/s per year, often correspond to regions of positive (negative) significant wave height trends. The cyclone and wind speed trends computed for the JFM months are well matched by the corresponding trends in significant wave height, with February being the month with the highest trends (negative south of 50°N up to -3 cm/year, and positive up to 5cm/year just north of Scotland). Using precipitation data from ECMWF reanalyses and a CRU high resolution dataset we show the impact of these trends in cyclone frequencies upon the corresponding precipitation trends in the influenced areas. It is also shown that these changes are partially linked to major shifts on the indices of large-scale patterns modes, namely the North Atlantic Oscillation (NAO), the Eastern Atlantic (EA) and the Scandinavian Patterns (SCAN). Trigo, I. F. 2006: Climatology and Interannual Variability of Storm-Tracks in

  14. Ecosystem Services Evaluation and Its Spatial Characteristics in Central Asia’s Arid Regions: A Case Study in Altay Prefecture, China

    Directory of Open Access Journals (Sweden)

    Qi Fu

    2015-06-01

    Full Text Available Ecosystem services are important foundations to realize the sustainable development of economy and society. The question of how to quantitatively evaluate ecosystem services in a scientific way is a hot topic among international researchers. Studying the spatial characteristics of ecosystem services in arid regions can provide the theoretical and practical basis for coordinating a sustainable man-land relationship. Altay Prefecture of China, a typical arid region in Central Asia, was taken as the study area. It is on the Silk Road economic belt, which is a key region in the program of developing Western China. Three ecosystem services: water yield, soil conservation, and net primary productivity were quantitatively evaluated. The results show that (1 the spatial distribution pattern has a distinct characteristic of zonality; (2 mountain zone and mountain-oasis ecotone are the hotspots of ecosystem services; and (3 the correlation between water yield and net primary productivity shows a gradual increasing trend as altitude decreases. Objective analysis from the aspect of mechanism is given by discussing the causes of this particular pattern. It is found that altitude and slope have great influence on spatial distributions of ecosystem services, zones with the most amount of services are distributed in 1.5–2 km-altitude and 15–25°-slope. Different human activities in different regions and spatial distance decay of ecosystem services also contribute to the formation of spatial pattern. Thus, overgrazing, logging and mining are prohibited in mountain zones and mountain-oasis ecotones. Scholars are encouraged to focus on desert-ecosystem services in the future.

  15. Trends that FCS Education Should Address: A Delphi Study Reveals Top 16

    Science.gov (United States)

    Alexander, Karen L.; Davis, Kimberlee

    2011-01-01

    This study used the Delphi method to identify trends of importance to family and consumer sciences (FCS) education. A panel of 21 FCS education experts identified 16 trends and evaluated them by importance, desirability, feasibility, and confidence in validity of the trend. Nutrition appeared as a top priority, followed by consumer economics. The…

  16. Recent shifts in Himalayan vegetation activity trends in response to climatic change and environmental drivers

    Science.gov (United States)

    Mishra, N. B.; Mainali, K. P.

    2016-12-01

    Climatic changes along with anthropogenic disturbances are causing dramatic ecological impacts in mid to high latitude mountain vegetation including in the Himalayas which are ecologically sensitive environments. Given the challenges associated with in situ vegetation monitoring in the Himalayas, remote sensing based quantification of vegetation dynamics can provide essential ecological information on changes in vegetation activity that may consist of alternative sequence of greening and/or browning periods. This study utilized a trend break analysis procedure for detection of monotonic as well as abrupt (either interruption or reversal) trend changes in smoothed normalized difference vegetation index satellite time-series data over the Himalayas. Overall, trend breaks in vegetation greenness showed high spatio-temporal variability in distribution considering elevation, ecoregion and land cover/use stratifications. Interrupted greening was spatially most dominant in all Himalayan ecoregions followed by abrupt browning. Areas showing trend reversal and monotonic trends appeared minority. Trend type distribution was strongly dependent on elevation as majority of greening (with or without interruption) occurred at lower elevation areas at higher elevation were dominantly. Ecoregion based stratification of trend types highlighted some exception to this elevational dependence as high altitude ecoregions of western Himalayas showed significantly less browning compared to the ecoregions in eastern Himalaya. Land cover/use based analysis of trend distribution showed that interrupted greening was most dominant in closed needleleafed forest following by rainfed cropland and mosaic croplands while interrupted browning most dominant in closed to open herbaceous vegetation found at higher elevation areas followed by closed needleleafed forest and closed to open broad leafed evergreen forests. Spatial analysis of trend break timing showed that for majority of areas experiencing

  17. Nuclear scanning microprobe: state of the art, applications and progress trends

    International Nuclear Information System (INIS)

    Ponomarev, A.G.

    2011-01-01

    The physical principles of nuclear scanning microprobe are considered. The analysis of state of the art of the microprobe setup from point of view of its spatial resolution and sensitivity of microanalysis techniques is given. The regions of nuclear microprobe applications are reviewed. The ways of spatial resolution and data acquisition system improvement under consideration of microprobe setup progress trends are considered. (authors)

  18. Brominated flame retardants in the Arctic. An overview of spatial and temporal trends

    Energy Technology Data Exchange (ETDEWEB)

    Wit, C de [Institute of Applied Environmental Research, Stockholm (Sweden); Alaee, M; Muir, D [National Water Research Institute, Burlington, MA (United States)

    2004-09-15

    The Stockholm Convention on Persistent Organic Pollutants (POPs), which entered into force on May 17, 2004, includes wording that chemicals with the characteristics of POPs are those found in locations ''distant from sources'' and those for which ''monitoring data showing that long-range environmental transport of the chemical may have occurred''. Thus, the Arctic has become an important indicator region for assessment of persistence and bioaccumulation. The Arctic environment is well suited as a region in which to evaluate POPs. Some regions of thee Arctic, particularly the Barents Sea area north of Norway and western Russia are relatively close to source regions of POPs. Cold conditions favor persistence of POPs relative to temperate or tropical environments. The presence of fourth level carnivores (e.g. polar bears and seabirds), and storage of lipid as an energy source, make Arctic food webs vulnerable to bioaccumulative chemicals. Indigenous people in the Arctic utilizing a traditional diet, which is high in nutritionally beneficial fat, results in their elevated exposure to some POPs. The first indication that brominated flame retardants (BFRs) were reaching the Arctic was the detection by Jansson et al. of lower molecular weight polybrominated diphenyl ethers (PBDEs) in Svalbard Brunnichfs guillemots (130 ng/g lipid weight) and ringed seals (40 ng/g lw) collected in 1981. Whitefish collected from Lake Storvindeln in 1986, a pristine mountain lake in the Swedish mountains near Ammarnas, had {sigma}PBDE levels of 26 ng/g lw. Despite these early findings, only recently have the spatial and temporal trends of BFRs been studied in detail in the Arctic. The purpose of this paper is to review the new data on BFRs in the Arctic and assess whether this information supports the view that PBDEs and other BFRs of similar molecular weight are POPs and potential global pollutants. This review is based on a recent assessment of POPs in the Arctic combined with newer data

  19. Brominated flame retardants in the Arctic. An overview of spatial and temporal trends

    Energy Technology Data Exchange (ETDEWEB)

    Wit, C. de [Institute of Applied Environmental Research, Stockholm (Sweden); Alaee, M.; Muir, D. [National Water Research Institute, Burlington, MA (United States)

    2004-09-15

    The Stockholm Convention on Persistent Organic Pollutants (POPs), which entered into force on May 17, 2004, includes wording that chemicals with the characteristics of POPs are those found in locations ''distant from sources'' and those for which ''monitoring data showing that long-range environmental transport of the chemical may have occurred''. Thus, the Arctic has become an important indicator region for assessment of persistence and bioaccumulation. The Arctic environment is well suited as a region in which to evaluate POPs. Some regions of thee Arctic, particularly the Barents Sea area north of Norway and western Russia are relatively close to source regions of POPs. Cold conditions favor persistence of POPs relative to temperate or tropical environments. The presence of fourth level carnivores (e.g. polar bears and seabirds), and storage of lipid as an energy source, make Arctic food webs vulnerable to bioaccumulative chemicals. Indigenous people in the Arctic utilizing a traditional diet, which is high in nutritionally beneficial fat, results in their elevated exposure to some POPs. The first indication that brominated flame retardants (BFRs) were reaching the Arctic was the detection by Jansson et al. of lower molecular weight polybrominated diphenyl ethers (PBDEs) in Svalbard Brunnichfs guillemots (130 ng/g lipid weight) and ringed seals (40 ng/g lw) collected in 1981. Whitefish collected from Lake Storvindeln in 1986, a pristine mountain lake in the Swedish mountains near Ammarnas, had {sigma}PBDE levels of 26 ng/g lw. Despite these early findings, only recently have the spatial and temporal trends of BFRs been studied in detail in the Arctic. The purpose of this paper is to review the new data on BFRs in the Arctic and assess whether this information supports the view that PBDEs and other BFRs of similar molecular weight are POPs and potential global pollutants. This review is based on a recent assessment of POPs

  20. Memory and Trend of Precipitation in China during 1966-2013

    Science.gov (United States)

    Du, M.; Sun, F.; Liu, W.

    2017-12-01

    As climate change has had a significant impact on water cycle, the characteristic and variation of precipitation under climate change turned into a hotspot in hydrology. This study aims to analyze the trend and memory (both short-term and long-term) of precipitation in China. To do that, we apply statistical tests (including Mann-Kendall test, Ljung-Box test and Hurst exponent) to annual precipitation (P), frequency of rainy day (λ) and mean daily rainfall in days when precipitation occurs (α) in China (1966-2013). We also use a resampling approach to determine the field significance. From there, we evaluate the spatial distribution and percentages of stations with significant memory or trend. We find that the percentages of significant downtrends for λ and significant uptrends for α are significantly larger than the critical values at 95% field significance level, probably caused by the global warming. From these results, we conclude that extra care is necessary when significant results are obtained using statistical tests. This is because the null hypothesis could be rejected by chance and this situation is more likely to occur if spatial correlation is ignored according to the results of the resampling approach.

  1. Warming Trends and Bleaching Stress of the World’s Coral Reefs 1985-2012

    Science.gov (United States)

    Heron, Scott F.; Maynard, Jeffrey A.; van Hooidonk, Ruben; Eakin, C. Mark

    2016-12-01

    Coral reefs across the world’s oceans are in the midst of the longest bleaching event on record (from 2014 to at least 2016). As many of the world’s reefs are remote, there is limited information on how past thermal conditions have influenced reef composition and current stress responses. Using satellite temperature data for 1985-2012, the analysis we present is the first to quantify, for global reef locations, spatial variations in warming trends, thermal stress events and temperature variability at reef-scale (~4 km). Among over 60,000 reef pixels globally, 97% show positive SST trends during the study period with 60% warming significantly. Annual trends exceeded summertime trends at most locations. This indicates that the period of summer-like temperatures has become longer through the record, with a corresponding shortening of the ‘winter’ reprieve from warm temperatures. The frequency of bleaching-level thermal stress increased three-fold between 1985-91 and 2006-12 - a trend climate model projections suggest will continue. The thermal history data products developed enable needed studies relating thermal history to bleaching resistance and community composition. Such analyses can help identify reefs more resilient to thermal stress.

  2. Spatial analyses of mono, di and trinucleotide trends in plant genes.

    Directory of Open Access Journals (Sweden)

    Andrea Porceddu

    Full Text Available Genomic DNA sequences display compositional heterogeneity on many scales. In this paper we analyzed tendencies and anomalies in the occurence of mono, di and trinucleotides in structural regions of plant genes. Representation of these trends as a function of position along genic sequences highlighted compositional features peculiar of either monocots or eudicots that were remarkably uniform within these two evolutionary clades. The most evident of these features appeared in the form of gradient of base content along the direction of transcription. The robustness of such a representation was validated in sequences sub-datasets generated considering structural and compositional features such as total length of cds, overall GC content and genic orientation in the genome. Piecewise regression analyses indicated that the gradients could be conveniently approximated to a two segmented model where a first region featuring a steep slope is followed by a second segment fitting a milder variation. In general, monocots species showed steeper segments than eudicots. The guanine gradient was the most distinctive feature between the two evolutionary clades, being moderately increasing in eudicots and firmly decreasing in monocots. Single gene investigation revealed that a high proportion of genes show compositional trends compatible with a segmented model suggesting that these features are essential attributes of gene organization. Dinucleotide and trinucleotide biases were referred to expectation based on a random union of the component elements. The average bias at dinucleotide level identified a significant undererpresentation of some dinucleotide and the overrepresention of others. The bias at trinucleotide level was on average low. Finally, the analysis of bryophyte coding sequences showed mononucleotide, dinucleotide and trinucleotide compositional trends resembling those of higher plants. This finding suggested that the emergenge of compositional bias

  3. Use and Limitations of a Climate-Quality Data Record to Study Temperature Trends on the Greenland Ice Sheet

    Science.gov (United States)

    Hall, Dorothy K.; Comiso, Josefino C.; Shuman, Christopher A.; Koenig, Lora S.; DiGirolamo, Nicolo E.

    2011-01-01

    Enhanced melting of the Greenland Ice Sheet has been documented in recent literature along with surface-temperature increases measured using infrared satellite data since 1981. Using a recently-developed climate-quality data record, 11- and 12-year trends in the clear-sky ice-surface temperature (IST) of the Greenland Ice Sheet have been studied using the Moderate-Resolution Imaging Spectroradiometer (MODIS) IST product. Daily and monthly MODIS ISTs of the Greenland Ice Sheet beginning on 1 March 2000 and continuing through 31 December 2010 are now available at 6.25-km spatial resolution on a polar stereographic grid as described in Hall et al. (submitted). This record will be elevated in status to a climate-data record (CDR) when more years of data become available either from the MODIS on the Terra or Aqua satellites, or from the Visible Infrared Imager Radiometer Suite (VIIRS) to be launched in October 2011. Maps showing the maximum extent of melt for the entire ice sheet and for the six major drainage basins have been developed from the MODIS IST dataset. Twelve-year trends of the duration of the melt season on the ice sheet vary in different drainage basins with some basins melting progressively earlier over the course of the study period. Some (but not all) of the basins also show a progressively-longer duration of melt. IST 12-year trends are compared with in-situ data, and climate data from the Modern Era Retrospective-Analysis for Research and Applications (MERRA) Reanalysis.

  4. Evaluating the power to detect temporal trends in fishery independent surveys: A case study based on Gillnets Set in the Ohio waters of Lake Erie for walleye

    Science.gov (United States)

    Wagner, Tyler; Vandergoot, Christopher S.; Tyson, Jeff

    2009-01-01

    Fishery-independent (FI) surveys provide critical information used for the sustainable management and conservation of fish populations. Because fisheries management often requires the effects of management actions to be evaluated and detected within a relatively short time frame, it is important that research be directed toward FI survey evaluation, especially with respect to the ability to detect temporal trends. Using annual FI gill-net survey data for Lake Erie walleyes Sander vitreus collected from 1978 to 2006 as a case study, our goals were to (1) highlight the usefulness of hierarchical models for estimating spatial and temporal sources of variation in catch per effort (CPE); (2) demonstrate how the resulting variance estimates can be used to examine the statistical power to detect temporal trends in CPE in relation to sample size, duration of sampling, and decisions regarding what data are most appropriate for analysis; and (3) discuss recommendations for evaluating FI surveys and analyzing the resulting data to support fisheries management. This case study illustrated that the statistical power to detect temporal trends was low over relatively short sampling periods (e.g., 5–10 years) unless the annual decline in CPE reached 10–20%. For example, if 50 sites were sampled each year, a 10% annual decline in CPE would not be detected with more than 0.80 power until 15 years of sampling, and a 5% annual decline would not be detected with more than 0.8 power for approximately 22 years. Because the evaluation of FI surveys is essential for ensuring that trends in fish populations can be detected over management-relevant time periods, we suggest using a meta-analysis–type approach across systems to quantify sources of spatial and temporal variation. This approach can be used to evaluate and identify sampling designs that increase the ability of managers to make inferences about trends in fish stocks.

  5. Recent warming trend in the coastal region of Qatar

    Science.gov (United States)

    Cheng, Way Lee; Saleem, Ayman; Sadr, Reza

    2017-04-01

    The objective of this study was to analyze long-term temperature-related phenomena in the eastern portion of the Middle East, focusing on the coastal region of Qatar. Extreme temperature indices were examined, which were defined by the Expert Team on Climate Change Detection and Indices, for Doha, Qatar; these indices were then compared with those from neighboring countries. The trends were calculated for a 30-year period (1983-2012), using hourly data obtained from the National Climatic Data Center. The results showed spatially consistent warming trends throughout the region. For Doha, 11 of the 12 indices studied showed significant warming trends. In particular, the warming trends were represented by an increase in the number of warm days and nights and a decrease in the number of cool nights and days. The high-temperature extremes during the night have risen at more than twice the rate of their corresponding daytime extremes. The intensity and frequency of hot days have increased, and the minimum temperature indices exhibited a higher rate of warming. The climatic changes in Doha are consistent with the region-wide heat-up in recent decades across the Middle East. However, the rapid economic expansion, increase of population since the 1990s, and urban effects in the region are thought to have intensified the rapidly warming climate pattern observed in Doha since the turn of the century.

  6. Spatial Visualization as Mediating between Mathematics Learning Strategy and Mathematics Achievement among 8th Grade Students

    Science.gov (United States)

    Rabab'h, Belal; Veloo, Arsaythamby

    2015-01-01

    Jordanian 8th grade students revealed low achievement in mathematics through four periods (1999, 2003, 2007 & 2011) of Trends in International Mathematics and Science Study (TIMSS). This study aimed to determine whether spatial visualization mediates the affect of Mathematics Learning Strategies (MLS) factors namely mathematics attitude,…

  7. Recent trends and patterns of Nigeria's industrial development ...

    African Journals Online (AJOL)

    This paper analyzes recent trend and the spatial patterns of manufacturing in Nigeria. In particular, the paper shows that industrial development in the country involved considerable craft works firms in the early stages and grew progressively in number over the years to large-scale manufacturing. The contribution of ...

  8. Improvement of tool support of the spatial approach to regional planning: problems, specifics, trends

    Directory of Open Access Journals (Sweden)

    Nataliya Gennadievna Yushkova

    2015-01-01

    Full Text Available The emerging imperatives of innovation economic development in Russia determine the content of conceptual and institutional constraints to the development of regional economic systems (RES. They consider the regional planning system as a leading priority in its inseparable unity with modern public administration tasks. However, the practice of development of long-term plans in the RF subjects proves that the innovation challenges of economic policy are not reflected properly in them or they are significantly distorted. The following reasons reduce the effectiveness of modernization processes in the RF subjects and hamper the appropriate reaction of RES on their impact: the lack of coordination between socio-economic and spatial regional plans, the imbalance of interaction between state authorities engaged in long-term planning, the lack of real prerequisites for the implementation of innovation initiatives in the regions. Systematization and analysis of long-term plans make it possible to substantiate the consistency of the spatial approach to regional planning expressed in the dominance of the transformational function that synchronizes the configuration and parameters of RES, and to establish ways to integrate spatial components in the system of regional planning through optimization of its tool support. The change in the content of the instrumentation support is based on the synthesis of the predominant basic characteristics of the existing tools used in isolated subsystems of regional planning of socio-economic and territorial development. The study has established a system of tool support for regional planning that adapts to the changes in both internal and external factors in the development of RES. Three main groups of tools: organizing, regulating, and coordinating are defined by their typing in accordance with the groups of management functions. The article proposes the modeling of combinations of tools that are subordinated to the

  9. Spatial variability of soil pH based on GIS combined with geostatistics in Panzhihua tobacco area

    International Nuclear Information System (INIS)

    Du Wei; Wang Changquan; Li Bing; Li Qiquan; Du Qian; Hu Jianxin; Liu Chaoke

    2012-01-01

    GIS and geostatistics were utilized to study the spatial variability of soil pH in Panzhihua tobacco area. Results showed that pH values in this area ranged from 4.5 to 8.3, especially 5.5 to 6.5, and in few areas were lower than 5.0 or higher than 7.0 which can meet the need of high-quality tobacco production. The best fitting model of variogram was exponential model with the nugget/sill of soil pH in 13.61% indicating strong spatial correlation. The change process was 5.40 km and the coefficient of determination was 0.491. The spatial variability of soil pH was mainly caused by structural factors such as cane, topography and soil type. The soil pH in Panzhihua tobacco area also showed a increasing trend of northwest to southeast trend. The pH of some areas in Caochang, Gonghe and Yumen were lower, and in Dalongtan were slightly higher. (authors)

  10. Drivers of Global Vegetation Biomass Trends between 1988 and 2008

    KAUST Repository

    McCabe, Matthew; Liu, Yi; Evans, Jason; De Jeu, Richard; van Dijk, Albert

    2013-01-01

    Vegetation optical depth (VOD) is an indicator of the vegetation water content of both woody and leaf components in terrestrial biomass as derived from passive microwave observations. VOD is distinctly different from products derived from optical remote sensing: it is less prone to saturation in dense canopy; is sensitive to both photosynthetic and non-photosynthetic biomass; is less affected by atmospheric conditions; and is of coarser spatial resolution. Here, VOD retrievals from a series of sensors are blended to produce a time series from 1988 through to 2008, and a global analysis is undertaken to quantify and attribute global VOD trends over the same period. We conduct Mann-Kendall linear trend tests on annual average VOD to identify regions of significant change. Patterns for these regions were evaluated against independent datasets to diagnose the underlying cause of the observed trends. Results indicate that: (1) over grassland and shrubland, VOD patterns correspond strongly to temporal precipitation patterns; (2) over croplands, annual average VOD shows a general increase that corresponds to reported crop yield patterns and can be attributed to a combination of precipitation patterns and agricultural improvement; (3) over humid tropical forest, the spatial pattern of VOD decline agrees well with deforestation patterns identified in previous studies; and (4) over boreal forests, regional VOD declines can be attributed to a combination of fires and logging. We conclude that VOD can be used to estimate and interpret global changes in total above ground vegetation biomass. We expect that this new observationally based remote sensing data source will be of considerable interest to hydrological, agricultural, climate change and carbon cycle studies, and provide new insights into these and related process investigations.

  11. Drivers of Global Vegetation Biomass Trends between 1988 and 2008

    KAUST Repository

    McCabe, Matthew

    2013-12-01

    Vegetation optical depth (VOD) is an indicator of the vegetation water content of both woody and leaf components in terrestrial biomass as derived from passive microwave observations. VOD is distinctly different from products derived from optical remote sensing: it is less prone to saturation in dense canopy; is sensitive to both photosynthetic and non-photosynthetic biomass; is less affected by atmospheric conditions; and is of coarser spatial resolution. Here, VOD retrievals from a series of sensors are blended to produce a time series from 1988 through to 2008, and a global analysis is undertaken to quantify and attribute global VOD trends over the same period. We conduct Mann-Kendall linear trend tests on annual average VOD to identify regions of significant change. Patterns for these regions were evaluated against independent datasets to diagnose the underlying cause of the observed trends. Results indicate that: (1) over grassland and shrubland, VOD patterns correspond strongly to temporal precipitation patterns; (2) over croplands, annual average VOD shows a general increase that corresponds to reported crop yield patterns and can be attributed to a combination of precipitation patterns and agricultural improvement; (3) over humid tropical forest, the spatial pattern of VOD decline agrees well with deforestation patterns identified in previous studies; and (4) over boreal forests, regional VOD declines can be attributed to a combination of fires and logging. We conclude that VOD can be used to estimate and interpret global changes in total above ground vegetation biomass. We expect that this new observationally based remote sensing data source will be of considerable interest to hydrological, agricultural, climate change and carbon cycle studies, and provide new insights into these and related process investigations.

  12. Age trends in economically important traits of Merino ewes ...

    African Journals Online (AJOL)

    Schalk Cloete

    Schalkwyk et al., 1999a), temperature and spatial position in the incubator (Van ... the eggs was fitted as a random effect, while female age, month of lay and the .... The trend for eggshell structure mirrored that of evaporation rate (Figure 1), ...

  13. Spatial and temporal patterns in preterm birth in the United States.

    Science.gov (United States)

    Byrnes, John; Mahoney, Richard; Quaintance, Cele; Gould, Jeffrey B; Carmichael, Suzan; Shaw, Gary M; Showen, Amy; Phibbs, Ciaran; Stevenson, David K; Wise, Paul H

    2015-06-01

    Despite years of research, the etiologies of preterm birth remain unclear. In order to help generate new research hypotheses, this study explored spatial and temporal patterns of preterm birth in a large, total-population dataset. Data on 145 million US births in 3,000 counties from the Natality Files of the National Center for Health Statistics for 1971-2011 were examined. State trends in early (birth rates were compared. K-means cluster analyses were conducted to identify gestational age distribution patterns for all US counties over time. A weak association was observed between state trends in birth rates and the initial absolute birth rate. Significant associations were observed between trends in birth rates and between white and African American births. Periodicity was observed in county-level trends in birth rates. Cluster analyses identified periods of significant heterogeneity and homogeneity in gestational age distributional trends for US counties. The observed geographic and temporal patterns suggest periodicity and complex, shared influences among preterm birth rates in the United States. These patterns could provide insight into promising hypotheses for further research.

  14. Modeling Urban Spatial Growth in Mountainous Regions of Western China

    Directory of Open Access Journals (Sweden)

    Guoping Huang

    2017-08-01

    Full Text Available The scale and speed of urbanization in the mountainous regions of western China have received little attention from researchers. These cities are facing rapid population growth and severe environmental degradation. This study analyzed historical urban growth trends in this mountainous region to better understand the interaction between the spatial growth pattern and the mountainous topography. Three major factors—slope, accessibility, and land use type—were studied in light of their relationships with urban spatial growth. With the analysis of historical data as the basis, a conceptual urban spatial growth model was devised. In this model, slope, accessibility, and land use type together create resistance to urban growth, while accessibility controls the sequence of urban development. The model was tested and evaluated using historical data. It serves as a potential tool for planners to envision and assess future urban growth scenarios and their potential environmental impacts to make informed decisions.

  15. Spatial trends of polybrominated diphenyl ethers in avian species: Utilization of stored samples in the Environmental Specimen Bank of Ehime University (es-Bank)

    International Nuclear Information System (INIS)

    Kunisue, Tatsuya; Higaki, Yumi; Isobe, Tomohiko; Takahashi, Shin; Subramanian, Annamalai; Tanabe, Shinsuke

    2008-01-01

    The present study determined concentrations and patterns of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in specimens of open sea, and Japanese coastal and inland avian species, which have been stored in the Environmental Specimen Bank of Ehime University (es-Bank), to examine the spatial trends. PBDEs and PCBs were detected in all the muscle samples analyzed, suggesting that PBDE pollution has spread even to the remote open sea areas, as in the case of PCBs. Japanese coastal and inland birds accumulated higher concentrations of PBDEs than open sea birds. In addition, higher PBDE/PCB concentration ratios were observed in Japanese coastal and inland birds than in open sea birds, indicating the input of PBDEs into the Japanese terrestrial environment. Compositions of PBDEs varied among avian species with a predominance of BDE47 or BDE153. This could be due to differences in their habitat, food habit and/or biotransformation capacity of PBDEs. - Open sea birds have been exposed to PBDEs, but the accumulation levels were lower than those in Japanese coastal and inland birds

  16. PHYSICAL SPATIAL DEVELOPMENT: A GIS ANALYSIS WITH EMPHASIS ON ENVIRONMENTAL IMPACTS-CASE STUDY NALOS CITY, IRAN

    Directory of Open Access Journals (Sweden)

    F. Naghibi, H. Shirmohammadi

    2008-01-01

    Full Text Available Unplanned urban developments have led to changes in uncontrollable urban spatial structure. For this reasons, informed guidance, principle organization and spatial planning are necessary for urban sprawl and development. In this research, different forms of urban development were considered and development basic barriers including rivers, topography, geology, ecological conditions, facilities and industries were determined and the role of each one was surveyed. Development trends that are based on effective parameters especially environmental impacts were modeled with Geographic Information Systems. The quality of urban planning and management can be upgraded when available and valid data are handled in an advanced manner with the aid of Geographic Information Systems. The innovative technology can support planning and decision making by offering relatively quick response on analytical questions and monitoring issues. Experienced expert determined the degree and primacy of urban sprawl and development parameters generally and for nalos case study, these parameters and criteria and their weights were marked, then were modeled with Geographic Information Systems for nalos developments. With using GIS and it capabilities in calculation of land size forecasting for Nalos development and its positioning we could take a step in planning directions such as sustainable development achievements.

  17. Recent history of trends in vegetation greenness and large-scale ecosystem disturbances in Eurasia

    International Nuclear Information System (INIS)

    Potter, Christopher; Nemani, Ramakrishna; Kumar, Vipin; Klooster, Steven

    2007-01-01

    Recent patterns of land cover and vegetation dynamics on the Euasian continent have been linked to changes in the global carbon cycle. Our study was conducted to evaluate patterns in a 19-yr record of global satellite observations of terrestrial vegetation from the Advanced Very High Resolution Radiometer (AVHRR) as a means to characterize major trends in both vegetation 'greenness' and ecosystem disturbance. The fraction absorbed of photosynthetically active radiation (FPAR) by vegetation canopies worldwide has been computed from the AVHRR at a monthly time interval from 1982 to 2000 and gridded at a spatial resolution of 8 km globally. Unlike previous studies of the AVHRR multiyear time-series of vegetation dynamics, the 8-km spatial resolution makes it possible to compare disturbance events and greenness trends at the same level of spatial detail. Positive trends in FPAR were detected throughout a major greenbelt of central-eastern Europe starting in the mid-1980s. This Eurasian greenbelt extended in a wide swath over the Urals, into the vicinity of Lake Baykal south of the central Siberian plateau, mainly along a latitude belt from 55 deg N to 65 deg N. There was also significantly positive greening in relatively large areas of Great Britain, Italy, Greece, Turkey, the Caucasus and southern India. Nonetheless, a strong downward trend in the FPAR time-series over most of Eurasia was observed by the end of the 1990s. Throughout the 19-yr time period, Eurasia was also impacted by many notable droughts and other disturbance events that could have substantially offset decadal carbon gains attributed to satellite-observed greening. Large-scale ecosystems disturbance events were identified in the FPAR time-series by locating anomalously low values (FPAR-LO) that lasted longer than 12 consecutive months at any 8-km pixel. We find verifiable evidence of numerous disturbance types across Eurasia, including regional patterns of severe droughts, forest fires and insect

  18. Trends in environmental science using microscopic X-ray fluorescence

    International Nuclear Information System (INIS)

    Fittschen, Ursula Elisabeth Adriane; Falkenberg, Gerald

    2011-01-01

    Microscopic X-ray fluorescence (micro-XRF) is a versatile tool in environmental analysis. We review work done in this field from 2008 to 2010 and highlight new aspects. Overall, there is a strong trend to combine fluorescence data with other data like diffraction or absorption spectroscopy. Also, the use of laboratory based instrumentation has become wide spread as more commercial instruments are available. At laboratories and synchrotron sites the trend towards higher spatial resolution is still persistent hitting sub micrometer values in case of synchrotron set ups.

  19. Trends in environmental science using microscopic X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Fittschen, Ursula Elisabeth Adriane, E-mail: ursula.fittschen@chemie.uni-hamburg.de [Department of Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Falkenberg, Gerald [Deutsches Elektronen-Synchrotron, Notkestr. 85, 22603 Hamburg (Germany)

    2011-08-15

    Microscopic X-ray fluorescence (micro-XRF) is a versatile tool in environmental analysis. We review work done in this field from 2008 to 2010 and highlight new aspects. Overall, there is a strong trend to combine fluorescence data with other data like diffraction or absorption spectroscopy. Also, the use of laboratory based instrumentation has become wide spread as more commercial instruments are available. At laboratories and synchrotron sites the trend towards higher spatial resolution is still persistent hitting sub micrometer values in case of synchrotron set ups.

  20. Anthropometric geography applied to the analysis of socioeconomic disparities: cohort trends and spatial patterns of height and robustness in 20th-century Spain.

    Science.gov (United States)

    Camara, Antonio D; Roman, Joan Garcia

    2015-11-01

    Anthropometrics have been widely used to study the influence of environmental factors on health and nutritional status. In contrast, anthropometric geography has not often been employed to approximate the dynamics of spatial disparities associated with socioeconomic and demographic changes. Spain exhibited intense disparity and change during the middle decades of the 20 th century, with the result that the life courses of the corresponding cohorts were associated with diverse environmental conditions. This was also true of the Spanish territories. This paper presents insights concerning the relationship between socioeconomic changes and living conditions by combining the analysis of cohort trends and the anthropometric cartography of height and physical build. This analysis is conducted for Spanish male cohorts born 1934-1973 that were recorded in the Spanish military statistics. This information is interpreted in light of region-level data on GDP and infant mortality. Our results show an anthropometric convergence across regions that, nevertheless, did not substantially modify the spatial patterns of robustness, featuring primarily robust northeastern regions and weak Central-Southern regions. These patterns persisted until the 1990s (cohorts born during the 1970s). For the most part, anthropometric disparities were associated with socioeconomic disparities, although the former lessened over time to a greater extent than the latter. Interestingly, the various anthropometric indicators utilized here do not point to the same conclusions. Some discrepancies between height and robustness patterns have been found that moderate the statements from the analysis of cohort height alone regarding the level and evolution of living conditions across Spanish regions.

  1. Precipitation and temperature trends over central Italy (Abruzzo Region): 1951-2012

    Science.gov (United States)

    Scorzini, Anna Rita; Leopardi, Maurizio

    2018-02-01

    This study analyses spatial and temporal trends of precipitation and temperatures over Abruzzo Region (central Italy), using historical climatic data from a dense observation network. The results show a general, although not significant, negative trend in the regionally averaged annual precipitation (- 1.8% of the yearly mean rainfall per decade). This reduction is particularly evident in winter, especially at mountain stations (average - 3% change/decade). Despite this general decreasing trend, a partial rainfall recovery is observed after the 1980s. Furthermore, the majority of meteorological stations register a significant warming over the last 60 years, (mean annual temperature increase of + 0.15 °C/decade), which reflects a rise in both minimum and maximum temperatures, with the latter generally increasing at a faster rate. Spring and summer are the seasons which contribute most to the general temperature increase, in particular at high elevation sites, which exhibit a more pronounced warming (+ 0.24 °C/decade). However, this tendency has not been uniform over 1951-2012, but it has been characterised by a cooling phenomenon in the first 30 years (1951-1981), followed by an even stronger warming during the last three decades (1982-2012). Finally, correlations between the climatic variables and the dominant teleconnection patterns in the Mediterranean basin are analysed to identify the potential influence of large-scale atmospheric dynamics on observed trends in Abruzzo. The results highlight the dominant role of the East-Atlantic pattern on seasonal temperatures, while more spatially heterogeneous associations, depending on the complex topography of the region, are identified between winter precipitation and the North Atlantic Oscillation, East-Atlantic and East-Atlantic/Western Russian patterns.

  2. Spatial analysis and characteristics of pig farming in Thailand.

    Science.gov (United States)

    Thanapongtharm, Weerapong; Linard, Catherine; Chinson, Pornpiroon; Kasemsuwan, Suwicha; Visser, Marjolein; Gaughan, Andrea E; Epprech, Michael; Robinson, Timothy P; Gilbert, Marius

    2016-10-06

    In Thailand, pig production intensified significantly during the last decade, with many economic, epidemiological and environmental implications. Strategies toward more sustainable future developments are currently investigated, and these could be informed by a detailed assessment of the main trends in the pig sector, and on how different production systems are geographically distributed. This study had two main objectives. First, we aimed to describe the main trends and geographic patterns of pig production systems in Thailand in terms of pig type (native, breeding, and fattening pigs), farm scales (smallholder and large-scale farming systems) and type of farming systems (farrow-to-finish, nursery, and finishing systems) based on a very detailed 2010 census. Second, we aimed to study the statistical spatial association between these different types of pig farming distribution and a set of spatial variables describing access to feed and markets. Over the last decades, pig population gradually increased, with a continuously increasing number of pigs per holder, suggesting a continuing intensification of the sector. The different pig-production systems showed very contrasted geographical distributions. The spatial distribution of large-scale pig farms corresponds with that of commercial pig breeds, and spatial analysis conducted using Random Forest distribution models indicated that these were concentrated in lowland urban or peri-urban areas, close to means of transportation, facilitating supply to major markets such as provincial capitals and the Bangkok Metropolitan region. Conversely the smallholders were distributed throughout the country, with higher densities located in highland, remote, and rural areas, where they supply local rural markets. A limitation of the study was that pig farming systems were defined from the number of animals per farm, resulting in their possible misclassification, but this should have a limited impact on the main patterns revealed

  3. Trends in High Nature Value farmland studies: A systematic review

    Directory of Open Access Journals (Sweden)

    Benedetti Yanina

    2017-12-01

    Full Text Available Background. Since the High Nature Value (HNV concept was defined in the early 1990s, several studies on HNV farmland has been increasing over the past 30 years in Europe, highlighting the interest by scientific community of HNV farming systems supporting biodiversity conservation. The aim of this study was to evaluate the trends and main gaps on HNV farmland peer-reviewed publications in order to contribute to the effectiveness of future research in this field. Methods. Searches were conducted using the databases Web of SciencesTM and Scopus in order to identify only peer-reviewed articles on HNV farmland, published prior to July 2017. The inclusion and exclusion criteria were developed a priori. Data as year, country, type of document, subject area, taxa studied and biodiversity metrics assessed were extracted and explored in order to analyse the spatial and temporal distribution of the concept, including the main topics addressed in HNV farmland literature. Results. After screening 308 original articles, 90 were selected for this review. HNV farmland studies involved several disciplines, mainly biodiversity and conservation and environmental sciences and ecology. Most peer-reviewed articles focused on HNV farming were conducted in Spain, Italy, Ireland and Portugal. The main studied taxa were plants and birds. Taxonomic diversity was the biodiversity metric more often used to assess the biodiversity status on HNV farmland areas. A positive correlation was found between HNV farmland area and HNV farmland studies conducted in respective countries. Discussion. The HNV farmland research subject is a relative novel approach, and this systematic review provides a comprehensive overview about the main topics in the HNV farmland peer-reviewed literature contributing to highlight the main gaps and provide some considerations in order to assist the performance of HNV farming systems and conservation policies, addressed to sustain high levels of

  4. Research and development studies on human factors: new trends

    International Nuclear Information System (INIS)

    Llory, M.; Larchier-Boulanger, J.

    1988-01-01

    This paper is aimed at describing where the research work on human factors undertaken at EDF stands in relation to this European trend and to define the problematics of cognitive phenomena in relation to all (non cognitive) human phenomena, on the one hand, and to individual aspects as compared to collective and organizational aspects, on the other. Some important trends in the research and development studies will thus be examined one lay one: - analysis of operators' activity; - analysis of the activity cognitive aspects; - problem of the impact of non-cognitive aspects

  5. Analysis and prediction of rainfall trends over Bangladesh using Mann-Kendall, Spearman's rho tests and ARIMA model

    Science.gov (United States)

    Rahman, Mohammad Atiqur; Yunsheng, Lou; Sultana, Nahid

    2017-08-01

    In this study, 60-year monthly rainfall data of Bangladesh were analysed to detect trends. Modified Mann-Kendall, Spearman's rho tests and Sen's slope estimators were applied to find the long-term annual, dry season and monthly trends. Sequential Mann-Kendall analysis was applied to detect the potential trend turning points. Spatial variations of the trends were examined using inverse distance weighting (IDW) interpolation. AutoRegressive integrated moving average (ARIMA) model was used for the country mean rainfall and for other two stations data which depicted the highest and the lowest trend in the Mann-Kendall and Spearman's rho tests. Results showed that there is no significant trend in annual rainfall pattern except increasing trends for Cox's Bazar, Khulna, Satkhira and decreasing trend for Srimagal areas. For the dry season, only Bogra area represented significant decreasing trend. Long-term monthly trends demonstrated a mixed pattern; both negative and positive changes were found from February to September. Comilla area showed a significant decreasing trend for consecutive 3 months while Rangpur and Khulna stations confirmed the significant rising trends for three different months in month-wise trends analysis. Rangpur station data gave a maximum increasing trend in April whereas a maximum decreasing trend was found in August for Comilla station. ARIMA models predict +3.26, +8.6 and -2.30 mm rainfall per year for the country, Cox's Bazar and Srimangal areas, respectively. However, all the test results and predictions revealed a good agreement among them in the study.

  6. Mixed layer depth trends in the Bay of Biscay over the period 1975-2010.

    Directory of Open Access Journals (Sweden)

    Xurxo Costoya

    Full Text Available Wintertime trends in mixed layer depth (MLD were calculated in the Bay of Biscay over the period 1975-2010 using the Simple Ocean Data Assimilation (SODA package. The reliability of the SODA database was confirmed correlating its results with those obtained from the experimental Argo database over the period 2003-2010. An iso-thermal layer depth (TLD and an iso-pycnal layer depth (PLD were defined using the threshold difference method with ΔT = 0.5°C and Δσθ = 0.125 kg/m3. Wintertime trends of the MLD were calculated using winter extended (December-March anomalies and annual maxima. Trends calculated for the whole Bay of Biscay using both parameters (TLD and PLD showed to be dependent on the area. Thus, MLD became deeper in the southeastern corner and shallower in the rest of the area. Air temperature was shown to play a key role in regulating the different spatial behavior of the MLD. Negative air temperature trends localized in the southeastern corner coincide with MLD deepening in this area, while, positive air temperature trends are associated to MLD shoaling in the rest of the bay. Additionally, the temperature trend calculated along the first 700 m of the water column is in good agreement with the different spatial behavior revealed for the MLD trend.

  7. [Studying dysfunctional personality trends among sex offenders].

    Science.gov (United States)

    Perrot, M; Bénony, H; Chahraoui, K; Juif, C

    2014-10-01

    A review of the literature reveals a consensus on the high prevalence of personality disorders among sexual offenders. Studies show that there is no unique personality profile for sex offenders. In France, little research has been conducted on this population with standardized assessment tools. The objective of the present study is to identify the distribution of personality disorders among sexual offenders using a new French questionnaire, i.e. the TD12. In view of the literature, we postulate that this tool will identify the diversity of personality disorders observed by various authors, but with a higher proportion of cluster B disorders. This study was conducted among 56 men, including 28 sex offenders aged from 21 to 70 years old, and a control group of 28 men without psychiatric disorders. The sex offenders in this study are men convicted or charged with sex offenses of various kinds: exhibitionism, the recording, distribution and possession of pornography depicting minors, aggravated corruption of a minor, sexual assault of a minor, or rape of a minor. They were examined using an inventory of dysfunctional trends recently developed by Rolland and Pichot with the aim of assessing dysfunctional personality styles. The TD-12 questionnaire is composed of 140 items describing thoughts, feelings and behaviors. It is based on the diagnostic criteria of Axis II of DSM IV-TR and consists of twelve scales that match the personality disorders described in this diagnostic manual (ten officially recognized disorders and two additional disorders). From a categorical viewpoint, results indicate rigid dysfunctional trends with regard to avoidant personality disorder in sex offenders compared to the control group (Chi(2)=9.16; P=0.005). However, there were no significant differences between the two groups regarding the number of rigid dysfunctional trends. Potentially controllable dysfunctional personality trends are identified for the dependent personality (Chi(2

  8. Trend analyses in the health behaviour in school-aged children study

    DEFF Research Database (Denmark)

    Schnohr, Christina W; Molcho, Michal; Rasmussen, Mette

    2015-01-01

    are considered. When analysing trends, researchers must be able to assess whether a change in prevalence is an expression of an actual change in the observed outcome, whether it is a result of methodological artefacts, or whether it is due to changes in the conceptualization of the outcome by the respondents....... CONCLUSION: The article present recommendations to take a number of the considerations into account. The considerations imply methodological challenges, which are core issues in undertaking trend analyses....... collecting data from adolescents aged 11-15 years, on a broad variety of health determinants and health behaviours. RESULTS: A number of methodological challenges have stemmed from the growth of the HBSC-study, in particular given that the study has a focus on monitoring trends. Some of those challenges...

  9. Long-term trends in total inorganic nitrogen and sulfur deposition in the US from 1990 to 2010

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2018-06-01

    Full Text Available Excess deposition (including both wet and dry deposition of nitrogen and sulfur is detrimental to ecosystems. Recent studies have investigated the spatial patterns and temporal trends of nitrogen and sulfur wet deposition, but few studies have focused on dry deposition due to the scarcity of dry deposition measurements. Here, we use long-term model simulations from the coupled Weather Research and Forecasting and the Community Multiscale Air Quality (WRF-CMAQ model covering the period from 1990 to 2010 to study changes in spatial distribution as well as temporal trends in total (TDEP, wet (WDEP, and dry deposition (DDEP of total inorganic nitrogen (TIN and sulfur (TS in the United States (US. We first evaluate the model's performance in simulating WDEP over the US by comparing the model results with observational data from the US National Atmospheric Deposition Program. The coupled model generally underestimates the WDEP of both TIN (including both the oxidized nitrogen deposition, TNO3, and the reduced nitrogen deposition, NHx and TS, with better performance in the eastern US than the western US. The underestimation of the wet deposition by the model is mainly caused by the coarse model grid resolution, missing lightning NOx emissions, and the poor temporal and spatial representation of NH3 emissions. TDEP of both TIN and TS shows significant decreases over the US, especially in the east, due to the large emission reductions that occurred in that region. The decreasing trends of TIN TDEP are caused by decreases in TNO3, and the increasing trends of TIN deposition over the Great Plains and Tropical Wet Forests (Southern Florida Coastal Plain regions are caused by increases in NH3 emissions, although it should be noted that these increasing trends are not significant. TIN WDEP shows decreasing trends throughout the US, except for the Marine West Coast Forest region. TIN DDEP shows significant decreasing trends in the Eastern Temperate Forests

  10. Spatial data analysis for exploration of regional scale geothermal resources

    Science.gov (United States)

    Moghaddam, Majid Kiavarz; Noorollahi, Younes; Samadzadegan, Farhad; Sharifi, Mohammad Ali; Itoi, Ryuichi

    2013-10-01

    Defining a comprehensive conceptual model of the resources sought is one of the most important steps in geothermal potential mapping. In this study, Fry analysis as a spatial distribution method and 5% well existence, distance distribution, weights of evidence (WofE), and evidential belief function (EBFs) methods as spatial association methods were applied comparatively to known geothermal occurrences, and to publicly-available regional-scale geoscience data in Akita and Iwate provinces within the Tohoku volcanic arc, in northern Japan. Fry analysis and rose diagrams revealed similar directional patterns of geothermal wells and volcanoes, NNW-, NNE-, NE-trending faults, hotsprings and fumaroles. Among the spatial association methods, WofE defined a conceptual model correspondent with the real world situations, approved with the aid of expert opinion. The results of the spatial association analyses quantitatively indicated that the known geothermal occurrences are strongly spatially-associated with geological features such as volcanoes, craters, NNW-, NNE-, NE-direction faults and geochemical features such as hotsprings, hydrothermal alteration zones and fumaroles. Geophysical data contains temperature gradients over 100 °C/km and heat flow over 100 mW/m2. In general, geochemical and geophysical data were better evidence layers than geological data for exploring geothermal resources. The spatial analyses of the case study area suggested that quantitative knowledge from hydrothermal geothermal resources was significantly useful for further exploration and for geothermal potential mapping in the case study region. The results can also be extended to the regions with nearly similar characteristics.

  11. THE EFFECTS OF SPATIAL SMOOTHING ON SOLAR MAGNETIC HELICITY PARAMETERS AND THE HEMISPHERIC HELICITY SIGN RULE

    Energy Technology Data Exchange (ETDEWEB)

    Ocker, Stella Koch [Department of Physics, Oberlin College, Oberlin, OH 44074 (United States); Petrie, Gordon, E-mail: socker@oberlin.edu, E-mail: gpetrie@nso.edu [National Solar Observatory, Boulder, CO 80303 (United States)

    2016-12-01

    The hemispheric preference for negative/positive helicity to occur in the northern/southern solar hemisphere provides clues to the causes of twisted, flaring magnetic fields. Previous studies on the hemisphere rule may have been affected by seeing from atmospheric turbulence. Using Hinode /SOT-SP data spanning 2006–2013, we studied the effects of two spatial smoothing tests that imitate atmospheric seeing: noise reduction by ignoring pixel values weaker than the estimated noise threshold, and Gaussian spatial smoothing. We studied in detail the effects of atmospheric seeing on the helicity distributions across various field strengths for active regions (ARs) NOAA 11158 and NOAA 11243, in addition to studying the average helicities of 179 ARs with and without smoothing. We found that, rather than changing trends in the helicity distributions, spatial smoothing modified existing trends by reducing random noise and by regressing outliers toward the mean, or removing them altogether. Furthermore, the average helicity parameter values of the 179 ARs did not conform to the hemisphere rule: independent of smoothing, the weak-vertical-field values tended to be negative in both hemispheres, and the strong-vertical-field values tended to be positive, especially in the south. We conclude that spatial smoothing does not significantly affect the overall statistics for space-based data, and thus seeing from atmospheric turbulence seems not to have significantly affected previous studies’ ground-based results on the hemisphere rule.

  12. Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation.

    Science.gov (United States)

    Du, Hai-Wen; Wang, Yong; Zhuang, Da-Fang; Jiang, Xiao-San

    2017-08-07

    The nest flea index of Meriones unguiculatus is a critical indicator for the prevention and control of plague, which can be used not only to detect the spatial and temporal distributions of Meriones unguiculatus, but also to reveal its cluster rule. This research detected the temporal and spatial distribution characteristics of the plague natural foci of Mongolian gerbils by body flea index from 2005 to 2014, in order to predict plague outbreaks. Global spatial autocorrelation was used to describe the entire spatial distribution pattern of the body flea index in the natural plague foci of typical Chinese Mongolian gerbils. Cluster and outlier analysis and hot spot analysis were also used to detect the intensity of clusters based on geographic information system methods. The quantity of M. unguiculatus nest fleas in the sentinel surveillance sites from 2005 to 2014 and host density data of the study area from 2005 to 2010 used in this study were provided by Chinese Center for Disease Control and Prevention. The epidemic focus regions of the Mongolian gerbils remain the same as the hot spot regions relating to the body flea index. High clustering areas possess a similar pattern as the distribution pattern of the body flea index indicating that the transmission risk of plague is relatively high. In terms of time series, the area of the epidemic focus gradually increased from 2005 to 2007, declined rapidly in 2008 and 2009, and then decreased slowly and began trending towards stability from 2009 to 2014. For the spatial change, the epidemic focus regions began moving northward from the southwest epidemic focus of the Mongolian gerbils from 2005 to 2007, and then moved from north to south in 2007 and 2008. The body flea index of Chinese gerbil foci reveals significant spatial and temporal aggregation characteristics through the employing of spatial autocorrelation. The diversity of temporary and spatial distribution is mainly affected by seasonal variation, the human

  13. PM2.5 and gaseous pollutants in New York State during 2005-2016: Spatial variability, temporal trends, and economic influences

    Science.gov (United States)

    Squizzato, Stefania; Masiol, Mauro; Rich, David Q.; Hopke, Philip K.

    2018-06-01

    Over the past decades, mitigation strategies have been adopted both by federal and state agencies in the United States (US) to improve air quality. Between 2007 and 2009, the US faced a financial/economic crisis that lowered activity and reduced emissions. At the same time, changes in the prices of coal and natural gas drove a shift in fuels used for electricity generation. Seasonal patterns, diel cycles, spatial gradients, and trends in PM2.5 and gaseous pollutants concentrations (NOx, SO2, CO and O3) monitored in New York State (NYS) from 2005 to 2016 were examined. Relationships between ambient concentrations, changes in NYS emissions retrieved from the US EPA trends inventory, and economic indicators were studied. PM2.5 and primary gaseous pollutants concentrations decreased across NYS. By 2016, PM2.5 and SO2 attained relatively homogeneous concentrations across the state. PM2.5 concentrations decreased significantly at all sites. Similarly, SO2 concentrations declined at all sites within this period, with the highest slopes observed at the urban sites. Reductions in NOx emissions likely contributed to summertime average ozone reductions. NOx and VOCs controls reduced O3 peak concentrations as seen in significant relationships between the annual O3 4th-highest daily maximum 8-h concentrations and estimated NOx emissions at rural and suburban sites (r2 ∼ 0.7). Spring maxima were not reduced with most sites showing insignificant slopes or significant positive slopes (e.g., +2.6% y-1 and +2% y-1, at CCNY and PFI, respectively). Increases in autumn and winter ozone concentrations were found (e,g., 6.6 ± 0.4% y-1 on average in New York City). Significant relationships were observed between PM2.5, primary pollutants, and economic indicators. Overall, a decrease in electricity generation with coal, and the simultaneous increase in natural gas consumption for power generation, led to a decrease in PM2.5 and gaseous pollutants concentrations.

  14. Assessing trends in observed and modelled climate extremes over Australia in relation to future projections

    International Nuclear Information System (INIS)

    Alexander, Lisa

    2007-01-01

    Full text: Nine global coupled climate models were assessed for their ability to reproduce observed trends in a set of indices representing temperature and precipitation extremes over Australia. Observed trends for 1957-1999 were compared with individual and multi-modelled trends calculated over the same period. When averaged across Australia the magnitude of trends and interannual variability of temperature extremes were well simulated by most models, particularly for the warm nights index. Except for consecutive dry days, the majority of models also reproduced the correct sign of trend for precipitation extremes. A bootstrapping technique was used to show that most models produce plausible trends when averaged over Australia, although only heavy precipitation days simulated from the multi-model ensemble showed significant skill at reproducing the observed spatial pattern of trends. Two of the models with output from different forcings showed that only with anthropogenic forcing included could the models capture the observed areally averaged trend for some of the temperature indices, but the forcing made little difference to the models' ability to reproduce the spatial pattern of trends over Australia. Future projected changes in extremes using three emissions scenarios were also analysed. Australia shows a shift towards significant warming of temperature extremes with much longer dry spells interspersed with periods of increased extreme precipitation irrespective of the scenario used. More work is required to determine whether regional projected changes over Australia are robust

  15. Modelled long term trends of surface ozone over South Africa

    CSIR Research Space (South Africa)

    Naidoo, M

    2011-10-01

    Full Text Available timescale seeks to provide a spatially comprehensive view of trends while also creating a baseline for comparisons with future projections of air quality through the forcing of air quality models with modelled predicted long term meteorology. Previous...

  16. Temporal and spatial trends in sediment contaminants associated with toxicity in California watersheds

    International Nuclear Information System (INIS)

    Siegler, Katie; Phillips, Bryn M.; Anderson, Brian S.; Voorhees, Jennifer P.; Tjeerdema, Ron S.

    2015-01-01

    California's Stream Pollution Trends program (SPoT) assesses long-term water quality trends, using 100 base-of-the-watershed sampling sites. Annual statewide sediment surveys from 2008 to 2012 identified consistent levels of statewide toxicity (19%), using the freshwater amphipod Hyalella azteca. Significant contaminant trends included a decrease in PCBs, stable concentrations of metals and PAHs, and a statewide increase in detections and concentrations of pyrethroid pesticides. The pyrethroid pesticide bifenthrin was detected in 69% of samples (n = 410). Detection of toxicity increased in a subset of samples tested at a more environmentally relevant test temperature (15 °C), and the magnitude of toxicity was much greater, indicating pyrethroid pesticides as a probable cause. Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. Principal components analysis related pyrethroids, metals and total organic carbon to urban land use. - Highlights: • Toxicity and contaminant concentrations were higher in urban dominated watersheds. • Average and range of total pyrethroid concentrations increased between 2008 and 2012. • Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. - Detections and concentrations of current use pesticides are increasing in California urban watersheds, while legacy organochlorine contaminants are decreasing statewide.

  17. Attribution of the Regional Patterns of North American Climate Trends

    Science.gov (United States)

    Hoerling, M.; Kumar, A.; Karoly, D.; Rind, D.; Hegerl, G.; Eischeid, J.

    2007-12-01

    North American trends in surface temperature and precipitation during 1951-2006 exhibit large spatial and seasonal variations. We seek to explain these by synthesizing new information based on existing model simulations of climate and its forcing, and based on modern reanalyses that describe past and current conditions within the free atmosphere. The presentation focuses on current capabilities to explain the spatial variations and seasonal differences in North American climate trends. It will address whether various heterogeneities in space and time can be accounted for by the climate system's sensitivity to time evolving anthropogenic forcing, and examines the influences of non-anthropogenic processes. New findings are presented that indicate anthropogenic forcing alone was unlikely the cause for key regional and seasonal patterns of change, including the absence of summertime warming over the Great Plains of the United States, and the absence of warming during both winter and summer over the southern United States. Key regional features are instead attributed to trends in the principal patterns of atmospheric flow that affect North American climate. It is demonstrated that observed variations in global sea surface temperatures have significantly influenced these patterns of atmospheric flow.

  18. Inferring Anthropogenic Trends from Satellite Data for Water-sustainability of US Cities Near Artificial Reservoirs

    Science.gov (United States)

    Yigzaw, W. Y.; Hossain, F.

    2015-12-01

    Impact of anthropogenic activities on water cycle and water supply has different effects at global and regional spatial scales, ensuing the need for a design and water management approach that considers anthropogenic inputs. One of the major inputs in local-to-regional availability of water and the water cycle are land use land cover change as a result of urbanization, artificial reservoirs and irrigation activity. This study employed a multi-factorial approach involving population trends, water use (and demand), streamflow; and various satellite derived water-relevant variables. These variables are: daily precipitation (from TRMM, 3B42.V7), Normalized Difference Vegetation Index-NDVI (from MODIS-MOD13A1), land surface temperature-LST (from MODIS-MOD11A2), and land cover (MODIS-MCD12Q1). Long terms exhibited by such data were used to understand temporal and spatial trends in impounded watersheds hosting a large and growing city in its proximity. The selected cities are: City of Atlanta-Georgia and Buford dam; Columbia-South Carolina and Saluda dam; Columbus-Ohio and Alum Creek dam; Montgomery-Alabama and Jordan dam; Tulsa-Oklahoma and Keystone dam; Tuscaloosa-Alabama and Tuscaloosa dam were selected. our study reveals that daily mean stream flow has been decreasing in all but one (Tulsa) of the areas selected. Satellite data trends between 2000 and 2012 showed a steady decrease in precipitation and NDVI; while LST has gradually increased. We attribute the NDVI (i.e., gradual decrease in vegetation cover) to LST rather than precipitation trends. The results of this research suggested that future temperature projection from climate models can be used in understanding vegetation activity and water availability over the study areas. Cities with larger upstream watershed area are potentially more sustainable and resilient (than those with small watersheds) as a result of spatial variability of water resources' response to climate change. Inter-basin water resources

  19. Evaluating the power to detect temporal trends in fishery-independent time surveys: A case study based on gill nets set in the Ohio waters of Lake Erie for walleyes

    Science.gov (United States)

    Wagner, Tyler; Vandergoot, Christopher S.; Tyson, Jeff

    2011-01-01

    Fishery-independent (FI) surveys provide critical information used for the sustainable management and conservation of fish populations. Because fisheries management often requires the effects of management actions to be evaluated and detected within a relatively short time frame, it is important that research be directed toward FI survey evaluation, especially with respect to the ability to detect temporal trends. Using annual FI gill-net survey data for Lake Erie walleyes Sander vitreus collected from 1978 to 2006 as a case study, our goals were to (1) highlight the usefulness of hierarchical models for estimating spatial and temporal sources of variation in catch per effort (CPE); (2) demonstrate how the resulting variance estimates can be used to examine the statistical power to detect temporal trends in CPE in relation to sample size, duration of sampling, and decisions regarding what data are most appropriate for analysis; and (3) discuss recommendations for evaluating FI surveys and analyzing the resulting data to support fisheries management. This case study illustrated that the statistical power to detect temporal trends was low over relatively short sampling periods (e.g., 5–10 years) unless the annual decline in CPE reached 10–20%. For example, if 50 sites were sampled each year, a 10% annual decline in CPE would not be detected with more than 0.80 power until 15 years of sampling, and a 5% annual decline would not be detected with more than 0.8 power for approximately 22 years. Because the evaluation of FI surveys is essential for ensuring that trends in fish populations can be detected over management-relevant time periods, we suggest using a meta-analysis–type approach across systems to quantify sources of spatial and temporal variation. This approach can be used to evaluate and identify sampling designs that increase the ability of managers to make inferences about trends in fish stocks.

  20. Effect of permethrin-treated bed nets on the spatial distribution of malaria vectors in western Kenya

    NARCIS (Netherlands)

    Gimnig, John E.; Kolczak, Margarette S.; Hightower, Allen W.; Vulule, John M.; Schoute, Erik; Kamau, Luna; Phillips-Howard, Penelope A.; ter Kuile, Feiko O.; Nahlen, Bernard L.; Hawley, William A.

    2003-01-01

    The effect of insecticide (permethrin)-treated bed nets (ITNs) on the spatial distribution of malaria vectors in neighboring villages lacking ITNs was studied during a randomized controlled trial of ITNs in western Kenya. There was a trend of decreased abundance of Anopheles gambiae with decreasing

  1. Spatial patterns of antimicrobial resistance genes in a cross-sectional sample of pig farms with indoor non-organic production of finishers

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Ersbøll, Annette Kjær; Hisham Beshara Halasa, Tariq

    2017-01-01

    Antimicrobial resistance (AMR) in pig populations is a public health concern. There is a lack of information of spatial distributions of AMR genes in pig populations at large scales. The objective of the study was to describe the spatial pattern of AMR genes in faecal samples from pig farms...... spatial clusters were identified for ermB, ermF, sulII and tet(W). The broad spatial trends in AMR resistance evident in the risk maps were in agreement with the results of the cluster analysis. However, they also showed that there were only small scale spatial differences in the gene levels. We conclude...

  2. Spatial and temporal pattern of eastern U. S. haziness: a summary

    Energy Technology Data Exchange (ETDEWEB)

    Husar, R B; Holloway, J M; Patterson, D E; Wilson, W E

    1981-01-01

    One of the key features of the optical environment over the eastern U.S. is the frequent occurrence of regional haziness, particularly during the summer season. Four historical data bases were examined for estimation of the regional trend in haziness over the past 80 years: the surface visibility observations currently operated by the National Weather Service; historical visibility at Blue Hill, MA; the NOAA-WMO Turbidity network measuring the extinction of solar radiation with a sun photometer since the 1960's; and a set of direct solar radiation monitoring stations operated since 1910. In the 1970's the lowest visibility occurred in the region of the Ohio River. The strongest increase of haziness was noted in the states adjacent to the Smoky Mountains: the average visibility there has decreased from 24 to 10 km since 1948. That region also exhibits the highest turbidity (vertical optical depth of the aerosol). The spatial trends of coal consumption indicate a consistency with the spatial trends in haziness.

  3. Auditory and visual spatial impression: Recent studies of three auditoria

    Science.gov (United States)

    Nguyen, Andy; Cabrera, Densil

    2004-10-01

    Auditory spatial impression is widely studied for its contribution to auditorium acoustical quality. By contrast, visual spatial impression in auditoria has received relatively little attention in formal studies. This paper reports results from a series of experiments investigating the auditory and visual spatial impression of concert auditoria. For auditory stimuli, a fragment of an anechoic recording of orchestral music was convolved with calibrated binaural impulse responses, which had been made with the dummy head microphone at a wide range of positions in three auditoria and the sound source on the stage. For visual stimuli, greyscale photographs were used, taken at the same positions in the three auditoria, with a visual target on the stage. Subjective experiments were conducted with auditory stimuli alone, visual stimuli alone, and visual and auditory stimuli combined. In these experiments, subjects rated apparent source width, listener envelopment, intimacy and source distance (auditory stimuli), and spaciousness, envelopment, stage dominance, intimacy and target distance (visual stimuli). Results show target distance to be of primary importance in auditory and visual spatial impression-thereby providing a basis for covariance between some attributes of auditory and visual spatial impression. Nevertheless, some attributes of spatial impression diverge between the senses.

  4. Recent Trends and Patterns of Gasoline Consumption in Nigeria ...

    African Journals Online (AJOL)

    This article analyses recent trends and spatial patterns of gasoline consumption in Nigeria. In particular, it shows that the volume of gasoline consumption in the country fluctuates with changes in economic growth. The pattern of distribution of gasoline consumption indicates that the largest consumption centres are in the ...

  5. Trends in Educational Augmented Reality Studies: A Systematic Review

    Science.gov (United States)

    Sirakaya, Mustafa; Alsancak Sirakaya, Didem

    2018-01-01

    This study aimed to identify the trends in the studies conducted on Educational Augmented Reality (AR). 105 articles found in ERIC, EBSCOhost and ScienceDirect databases were reviewed with this purpose in mind. Analyses displayed that the number of educational AR studies has increased over the years. Quantitative methods were mostly preferred in…

  6. Local Vegetation Trends in the Sahel of Mali and Senegal Using Long Time Series FAPAR Satellite Products and Field Measurement (1982–2010

    Directory of Open Access Journals (Sweden)

    Martin Brandt

    2014-03-01

    Full Text Available Local vegetation trends in the Sahel of Mali and Senegal from Geoland Version 1 (GEOV1 (5 km and the third generation Global Inventory Modeling and Mapping Studies (GIMMS3g (8 km Fraction of Absorbed Photosynthetically Active Radiation (FAPAR time series are studied over 29 years. For validation and interpretation of observed greenness trends, two methods are applied: (1 a qualitative approach using in-depth knowledge of the study areas and (2 a quantitative approach by time series of biomass observations and rainfall data. Significant greening trends from 1982 to 2010 are consistently observed in both GEOV1 and GIMMS3g FAPAR datasets. Annual rainfall increased significantly during the observed time period, explaining large parts of FAPAR variations at a regional scale. Locally, GEOV1 data reveals a heterogeneous pattern of vegetation change, which is confirmed by long-term ground data and site visits. The spatial variability in the observed vegetation trends in the Sahel area are mainly caused by varying tree- and land-cover, which are controlled by human impact, soil and drought resilience. A large proportion of the positive trends are caused by the increment in leaf biomass of woody species that has almost doubled since the 1980s due to a tree cover regeneration after a dry-period. This confirms the re-greening of the Sahel, however, degradation is also present and sometimes obscured by greening. GEOV1 as compared to GIMMS3g made it possible to better characterize the spatial pattern of trends and identify the degraded areas in the study region.

  7. Spatial and temporal characteristics of droughts in Luanhe River basin, China

    Science.gov (United States)

    Wang, Yixuan; Zhang, Ting; Chen, Xu; Li, Jianzhu; Feng, Ping

    2018-02-01

    The spatial and temporal characteristics of drought are investigated for Luanhe River basin, using monthly precipitation data from 26 stations covering the common period of 1958-2011. The spatial pattern of drought was assessed by applying principal component analysis (PCA) to the Standardized Precipitation Index (SPI) computed on 3- and 12-month time scales. In addition, annual SPI and seasonal SPIs (including spring SPI, summer SPI, autumn SPI, and winter SPI) were also defined and considered in this study to characterize seasonal and annual drought conditions, respectively. For all seven SPI cases, three distinctive sub-regions with different temporal evolutions of droughts are well identified, respectively, representing the southeast, middle, and northwest of the Luanhe River basin. The Mann-Kendall (MK) trend test with a trend-free pre-whitening (TFPW) procedure and Sen's method were used to determine the temporal trends in the annual and seasonal SPI time series. The continuous wavelet transform (CWT) was employed for further detecting the periodical features of drought condition in each sub-region. Results of MK and Sen's tests show a general tendency of intensification in summer drought over the entire basin, while a significant mitigating trend in spring drought. On the whole, an aggravating trend of inter-annual drought is discovered across the basin. Based on the CWT, the drought variability in the basin is generally dominated by 16- to 64-month cycles, and the 2- to 6-year cycles appear to be obvious when concerned with annual and seasonal droughts. Furthermore, a cross wavelet analysis was performed to examine the possible links between the drought conditions and large-scale climate patterns. The teleconnections of ENSO, NAO, PDO, and AMO show significant influences on the regional droughts principally concentrated in the 16- to 64-month period, maybe responsible for the physical causes of the cyclical behavior of drought occurrences. PDO and AMO also

  8. Precipitation collector bias and its effects on temporal trends and spatial variability in National Atmospheric Deposition Program/National Trends Network data

    Science.gov (United States)

    Wetherbee, Gregory A.

    2017-01-01

    Precipitation samples have been collected by the National Atmospheric Deposition Program's (NADP) National Trends Network (NTN) using the Aerochem Metrics Model 301 (ACM) collector since 1978. Approximately one-third of the NTN ACM collectors have been replaced with N-CON Systems, Inc. Model ADS 00-120 (NCON) collectors. Concurrent data were collected over 6 years at 12 NTN sites using colocated ACM and NCON collectors in various precipitation regimes. Linear regression models of the colocated data were used to adjust for relative bias between the collectors. Replacement of ACM collectors with NCON collectors resulted in shifts in 10-year seasonal precipitation-weighted mean concentration (PWMC) trend slopes for: cations (−0.001 to −0.007 mgL−1yr−1), anions (−0.009 to −0.028 mgL−1yr−1), and hydrogen ion (+0.689 meqL-1yr−1). Larger shifts in NO3− and SO4−2 seasonal PWMC trend slopes were observed in the Midwest and Northeast US, where concentrations are generally higher than in other regions. Geospatial analysis of interpolated concentration rasters indicated regions of accentuated variability introduced by incorporation of NCON collectors into the NTN.

  9. A climate trend analysis of Kenya-August 2010

    Science.gov (United States)

    Funk, Christopher C.

    2010-01-01

    Introduction This brief report draws from a multi-year effort by the United States Agency for International Development's Famine Early Warning System Network (FEWS NET) to monitor and map rainfall and temperature trends over the last 50 years (1960-2009) in Kenya. Observations from seventy rainfall gauges and seventeen air temperature stations were analyzed for the long rains period, corresponding to March through June (MAMJ). The data were quality controlled, converted into 1960-2009 trend estimates, and interpolated using a rigorous geo-statistical technique (kriging). Kriging produces standard error estimates, and these can be used to assess the relative spatial accuracy of the identified trends. Dividing the trends by the associated errors allows us to identify the relative certainty of our estimates (Funk and others, 2005; Verdin and others, 2005; Brown and Funk, 2008; Funk and Verdin, 2009). Assuming that the same observed trends persist, regardless of whether or not these changes are due to anthropogenic or natural cyclical causes, these results can be extended to 2025, providing critical, and heretofore missing information about the types and locations of adaptation efforts that may be required to improve food security.

  10. The spatial diffusion of norovirus epidemics over three seasons in Tokyo.

    Science.gov (United States)

    Inaida, S; Shobugawa, Y; Matsuno, S; Saito, R; Suzuki, H

    2015-02-01

    We studied the spatial trend of norovirus (NoV) epidemics using sentinel gastroenteritis surveillance data for patients aged spreading pattern of NoV epidemics using sentinel surveillance data. Correlations of sentinel cases between the seasons and with demographic data were examined to identify the trend and related factors. A similar pattern of diffusion was observed over the seasons, and its mean correlation between seasons was significantly high. A higher number of cases were found in the peripheral area, which surrounds the most populated central area, and showed a correlation with the ratio of the children population (r = 0·321, P epidemic factor. Prevention with focus on the peripheral area is desirable.

  11. Evaluation of carbon fluxes and trends (2000-2008) in the Greater Platte River Basin: a sustainability study on the potential biofuel feedstock development

    Science.gov (United States)

    Gu, Yingxin; Wylie, Bruce K.; Zhang, Li; Gilmanov, Tagir G.

    2012-01-01

    This study evaluates the carbon fluxes and trends and examines the environmental sustainability (e.g., carbon budget, source or sink) of the potential biofuel feedstock sites identified in the Greater Platte River Basin (GPRB). A 9-year (2000–2008) time series of net ecosystem production (NEP), a measure of net carbon absorption or emission by ecosystems, was used to assess the historical trends and budgets of carbon flux for grasslands in the GPRB. The spatially averaged annual NEP (ANEP) for grassland areas that are possibly suitable for biofuel expansion (productive grasslands) was 71–169 g C m−2 year−1 during 2000–2008, indicating a carbon sink (more carbon is absorbed than released) in these areas. The spatially averaged ANEP for areas not suitable for biofuel feedstock development (less productive or degraded grasslands) was −47 to 69 g C m−2 year−1 during 2000–2008, showing a weak carbon source or a weak carbon sink (carbon emitted is nearly equal to carbon absorbed). The 9-year pre-harvest cumulative ANEP was 1166 g C m−2 for the suitable areas (a strong carbon sink) and 200 g C m−2 for the non-suitable areas (a weak carbon sink). Results demonstrate and confirm that our method of dynamic modeling of ecosystem performance can successfully identify areas desirable and sustainable for future biofuel feedstock development. This study provides useful information for land managers and decision makers to make optimal land use decisions regarding biofuel feedstock development and sustainability.

  12. Participative Spatial Scenario Analysis for Alpine Ecosystems

    Science.gov (United States)

    Kohler, Marina; Stotten, Rike; Steinbacher, Melanie; Leitinger, Georg; Tasser, Erich; Schirpke, Uta; Tappeiner, Ulrike; Schermer, Markus

    2017-10-01

    Land use and land cover patterns are shaped by the interplay of human and ecological processes. Thus, heterogeneous cultural landscapes have developed, delivering multiple ecosystem services. To guarantee human well-being, the development of land use types has to be evaluated. Scenario development and land use and land cover change models are well-known tools for assessing future landscape changes. However, as social and ecological systems are inextricably linked, land use-related management decisions are difficult to identify. The concept of social-ecological resilience can thereby provide a framework for understanding complex interlinkages on multiple scales and from different disciplines. In our study site (Stubai Valley, Tyrol/Austria), we applied a sequence of steps including the characterization of the social-ecological system and identification of key drivers that influence farmers' management decisions. We then developed three scenarios, i.e., "trend", "positive" and "negative" future development of farming conditions and assessed respective future land use changes. Results indicate that within the "trend" and "positive" scenarios pluri-activity (various sources of income) prevents considerable changes in land use and land cover and promotes the resilience of farming systems. Contrarily, reductions in subsidies and changes in consumer behavior are the most important key drivers in the negative scenario and lead to distinct abandonment of grassland, predominantly in the sub-alpine zone of our study site. Our conceptual approach, i.e., the combination of social and ecological methods and the integration of local stakeholders' knowledge into spatial scenario analysis, resulted in highly detailed and spatially explicit results that can provide a basis for further community development recommendations.

  13. Seasonal and annual precipitation time series trend analysis in North Carolina, United States

    Science.gov (United States)

    Sayemuzzaman, Mohammad; Jha, Manoj K.

    2014-02-01

    The present study performs the spatial and temporal trend analysis of the annual and seasonal time-series of a set of uniformly distributed 249 stations precipitation data across the state of North Carolina, United States over the period of 1950-2009. The Mann-Kendall (MK) test, the Theil-Sen approach (TSA) and the Sequential Mann-Kendall (SQMK) test were applied to quantify the significance of trend, magnitude of trend, and the trend shift, respectively. Regional (mountain, piedmont and coastal) precipitation trends were also analyzed using the above-mentioned tests. Prior to the application of statistical tests, the pre-whitening technique was used to eliminate the effect of autocorrelation of precipitation data series. The application of the above-mentioned procedures has shown very notable statewide increasing trend for winter and decreasing trend for fall precipitation. Statewide mixed (increasing/decreasing) trend has been detected in annual, spring, and summer precipitation time series. Significant trends (confidence level ≥ 95%) were detected only in 8, 7, 4 and 10 nos. of stations (out of 249 stations) in winter, spring, summer, and fall, respectively. Magnitude of the highest increasing (decreasing) precipitation trend was found about 4 mm/season (- 4.50 mm/season) in fall (summer) season. Annual precipitation trend magnitude varied between - 5.50 mm/year and 9 mm/year. Regional trend analysis found increasing precipitation in mountain and coastal regions in general except during the winter. Piedmont region was found to have increasing trends in summer and fall, but decreasing trend in winter, spring and on an annual basis. The SQMK test on "trend shift analysis" identified a significant shift during 1960 - 70 in most parts of the state. Finally, the comparison between winter (summer) precipitations with the North Atlantic Oscillation (Southern Oscillation) indices concluded that the variability and trend of precipitation can be explained by the

  14. Spatial heterogeneity study of vegetation coverage at Heihe River Basin

    Science.gov (United States)

    Wu, Lijuan; Zhong, Bo; Guo, Liyu; Zhao, Xiangwei

    2014-11-01

    Spatial heterogeneity of the animal-landscape system has three major components: heterogeneity of resource distributions in the physical environment, heterogeneity of plant tissue chemistry, heterogeneity of movement modes by the animal. Furthermore, all three different types of heterogeneity interact each other and can either reinforce or offset one another, thereby affecting system stability and dynamics. In previous studies, the study areas are investigated by field sampling, which costs a large amount of manpower. In addition, uncertain in sampling affects the quality of field data, which leads to unsatisfactory results during the entire study. In this study, remote sensing data is used to guide the sampling for research on heterogeneity of vegetation coverage to avoid errors caused by randomness of field sampling. Semi-variance and fractal dimension analysis are used to analyze the spatial heterogeneity of vegetation coverage at Heihe River Basin. The spherical model with nugget is used to fit the semivariogram of vegetation coverage. Based on the experiment above, it is found, (1)there is a strong correlation between vegetation coverage and distance of vegetation populations within the range of 0-28051.3188m at Heihe River Basin, but the correlation loses suddenly when the distance greater than 28051.3188m. (2)The degree of spatial heterogeneity of vegetation coverage at Heihe River Basin is medium. (3)Spatial distribution variability of vegetation occurs mainly on small scales. (4)The degree of spatial autocorrelation is 72.29% between 25% and 75%, which means that spatial correlation of vegetation coverage at Heihe River Basin is medium high.

  15. Spatial policy, planning and infrastructure investment: Lessons from ...

    African Journals Online (AJOL)

    More evidence, and better evidence, an understanding of spatial trends and the underlying forces that shape them, are needed to support planning and infrastructure investment. Urban simulation platforms offer valuable tools in this regard. Findings of simulation work in three metropolitan areas (eThekwini, Nelson Mandela ...

  16. [Spatial-temporal pattern and obstacle factors of cultivated land ecological security in major grain producing areas of northeast China: a case study in Jilin Province].

    Science.gov (United States)

    Zhao, Hong-Bo; Ma, Yan-Ji

    2014-02-01

    According to the cultivated land ecological security in major grain production areas of Northeast China, this paper selected 48 counties of Jilin Province as the research object. Based on the PSR-EES conceptual framework model, an evaluation index system of cultivated land ecological security was built. By using the improved TOPSIS, Markov chains, GIS spatial analysis and obstacle degree models, the spatial-temporal pattern of cultivated land ecological security and the obstacle factors were analyzed from 1995 to 2011 in Jilin Province. The results indicated that, the composite index of cultivated land ecological security appeared in a rising trend in Jilin Province from 1995 to 2011, and the cultivated land ecological security level changed from being sensitive to being general. There was a pattern of 'Club Convergence' in cultivated land ecological security level in each county and the spatial discrepancy tended to become larger. The 'Polarization' trend of cultivated land ecological security level was obvious. The distributions of sensitive level and critical security level with ribbon patterns tended to be dispersed, the general security level and relative security levels concentrated, and the distributions of security level scattered. The unstable trend of cultivated land ecological security level was more and more obvious. The main obstacle factors that affected the cultivated land ecological security level in Jilin Province were rural net income per capita, economic density, the proportion of environmental protection investment in GDP, degree of machinery cultivation and the comprehensive utilization rate of industrial solid wastes.

  17. Balancing geo-privacy and spatial patterns in epidemiological studies

    Directory of Open Access Journals (Sweden)

    Chien-Chou Chen

    2017-11-01

    Full Text Available To balance the protection of geo-privacy and the accuracy of spatial patterns, we developed a geo-spatial tool (GeoMasker intended to mask the residential locations of patients or cases in a geographic information system (GIS. To elucidate the effects of geo-masking parameters, we applied 2010 dengue epidemic data from Taiwan testing the tool’s performance in an empirical situation. The similarity of pre- and post-spatial patterns was measured by D statistics under a 95% confidence interval. In the empirical study, different magnitudes of anonymisation (estimated Kanonymity ≥10 and 100 were achieved and different degrees of agreement on the pre- and post-patterns were evaluated. The application is beneficial for public health workers and researchers when processing data with individuals’ spatial information.

  18. Elasmobranch spatial segregation in the western Mediterranean

    Directory of Open Access Journals (Sweden)

    Adam Gouraguine

    2011-07-01

    Full Text Available Basic information on the distribution and habitat preferences of ecologically important species is essential for their management and protection. This study focuses on the depth related trends and the geographic patterns that shape the community of the elasmobranch species in the Balearic Islands (Mediterranean Sea using data collected from 2001 to 2009. Non-metric Multi-Dimensional Scaling (MDS ordination was used to detect zonation patterns in the community. Generalized Additive Models (GAMs were applied to analyse spatial and temporal variation in elasmobranch community descriptors (abundance, biomass, mean fish weight, number of species and diversity, as well as the abundance and mean length of the four individual species (S. canicula, G. melastomus, R. clavata, R. miraletus. Depth was the main factor determining the assemblage composition, and the MDS analysis identified four main groups with 60% of the similarity found to correspond to the continental shelf, shelf break, upper slope and middle slope of the surveyed area. GAM analysis identified spatial patterns that were independent of the bathymetric distribution preference. Although depth was a strong predictor for all the analyses performed, the geographic variation in the elasmobranch abundance was also important. The results also show a reduction in the mean length of the elasmobranch species in the areas with high fishing intensity. Our study evidences a clear spatial segregation of the main species throughout the ontogeny because the geographic and bathymetric effects were highly size dependent, with clear differences between the bathymetric distributions of juveniles and adults but no clear spatial overlapping. This study sheds new light on the spatial distribution of the elasmobranch species off the Balearic Islands, which is essential information for protecting marine organisms along with their habitats and promoting ecosystem based management.

  19. Spatial data analysis and integration for regional-scale geothermal potential mapping, West Java, Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Carranza, Emmanuel John M.; Barritt, Sally D. [Department of Earth Systems Analysis, International Institute for Geo-information Science and Earth Observation (ITC), Enschede (Netherlands); Wibowo, Hendro; Sumintadireja, Prihadi [Laboratory of Volcanology and Geothermal, Geology Department, Institute of Technology Bandung (ITB), Bandung (Indonesia)

    2008-06-15

    Conceptual modeling and predictive mapping of potential for geothermal resources at the regional-scale in West Java are supported by analysis of the spatial distribution of geothermal prospects and thermal springs, and their spatial associations with geologic features derived from publicly available regional-scale spatial data sets. Fry analysis shows that geothermal occurrences have regional-scale spatial distributions that are related to Quaternary volcanic centers and shallow earthquake epicenters. Spatial frequency distribution analysis shows that geothermal occurrences have strong positive spatial associations with Quaternary volcanic centers, Quaternary volcanic rocks, quasi-gravity lows, and NE-, NNW-, WNW-trending faults. These geological features, with their strong positive spatial associations with geothermal occurrences, constitute spatial recognition criteria of regional-scale geothermal potential in a study area. Application of data-driven evidential belief functions in GIS-based predictive mapping of regional-scale geothermal potential resulted in delineation of high potential zones occupying 25% of West Java, which is a substantial reduction of the search area for further exploration of geothermal resources. The predicted high potential zones delineate about 53-58% of the training geothermal areas and 94% of the validated geothermal occurrences. The results of this study demonstrate the value of regional-scale geothermal potential mapping in: (a) data-poor situations, such as West Java, and (b) regions with geotectonic environments similar to the study area. (author)

  20. Spatial filtring and thermocouple spatial filter

    International Nuclear Information System (INIS)

    Han Bing; Tong Yunxian

    1989-12-01

    The design and study on thermocouple spatial filter have been conducted for the flow measurement of integrated reactor coolant. The fundamental principle of spatial filtring, mathematical descriptions and analyses of thermocouple spatial filter are given

  1. Spatial memory extinction: a c-Fos protein mapping study.

    Science.gov (United States)

    Méndez-Couz, M; Conejo, N M; Vallejo, G; Arias, J L

    2014-03-01

    While the neuronal basis of spatial memory consolidation has been thoroughly studied, the substrates mediating the process of extinction remain largely unknown. This study aimed to evaluate the functional contribution of selected brain regions during the extinction of a previously acquired spatial memory task in the Morris water maze. For that purpose, we used adult male Wistar rats trained in a spatial reference memory task. Learning-related changes in c-Fos inmunoreactive cells after training were evaluated in cortical and subcortical regions. Results show that removal of the hidden platform in the water maze induced extinction of the previously reinforced escape behavior after 16 trials, without spontaneous recovery 24h later. Extinction was related with significantly higher numbers of c-Fos positive nuclei in amygdala nuclei and prefrontal cortex. On the other hand, the lateral mammillary bodies showed higher number of c-Fos positive cells than the control group. Therefore, in contrast with the results obtained in studies of classical conditioning, we show the involvement of diencephalic structures mediating this kind of learning. In summary, our findings suggest that medial prefrontal cortex, the amygdala complex and diencephalic structures like the lateral mammillary nuclei are relevant for the extinction of spatial memory. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Prevailing climatic trends and runoff response from Hindukush–Karakoram–Himalaya, upper Indus Basin

    Directory of Open Access Journals (Sweden)

    S. U. Hasson

    2017-05-01

    Full Text Available Largely depending on the meltwater from the Hindukush–Karakoram–Himalaya, withdrawals from the upper Indus Basin (UIB contribute half of the surface water availability in Pakistan, indispensable for agricultural production systems, industrial and domestic use, and hydropower generation. Despite such importance, a comprehensive assessment of prevailing state of relevant climatic variables determining the water availability is largely missing. Against this background, this study assesses the trends in maximum, minimum and mean temperatures, diurnal temperature range and precipitation from 18 stations (1250–4500 m a.s.l. for their overlapping period of record (1995–2012 and, separately, from six stations of their long-term record (1961–2012. For this, a Mann–Kendall test on serially independent time series is applied to detect the existence of a trend, while its true slope is estimated using the Sen's slope method. Further, locally identified climatic trends are statistically assessed for their spatial-scale significance within 10 identified subregions of the UIB, and the spatially (field- significant climatic trends are then qualitatively compared with the trends in discharge out of corresponding subregions. Over the recent period (1995–2012, we find warming and drying of spring (field-significant in March and increasing early melt season discharge from most of the subregions, likely due to a rapid snowmelt. In stark contrast, most of the subregions feature a field-significant cooling within the monsoon period (particularly in July and September, which coincides well with the main glacier melt season. Hence, a decreasing or weakly increasing discharge is observed from the corresponding subregions during mid- to late melt season (particularly in July. Such tendencies, being largely consistent with the long-term trends (1961–2012, most likely indicate dominance of the nival but suppression of the glacial melt regime

  3. Prevailing climatic trends and runoff response from Hindukush-Karakoram-Himalaya, upper Indus Basin

    Science.gov (United States)

    Hasson, Shabeh ul; Böhner, Jürgen; Lucarini, Valerio

    2017-05-01

    Largely depending on the meltwater from the Hindukush-Karakoram-Himalaya, withdrawals from the upper Indus Basin (UIB) contribute half of the surface water availability in Pakistan, indispensable for agricultural production systems, industrial and domestic use, and hydropower generation. Despite such importance, a comprehensive assessment of prevailing state of relevant climatic variables determining the water availability is largely missing. Against this background, this study assesses the trends in maximum, minimum and mean temperatures, diurnal temperature range and precipitation from 18 stations (1250-4500 m a.s.l.) for their overlapping period of record (1995-2012) and, separately, from six stations of their long-term record (1961-2012). For this, a Mann-Kendall test on serially independent time series is applied to detect the existence of a trend, while its true slope is estimated using the Sen's slope method. Further, locally identified climatic trends are statistically assessed for their spatial-scale significance within 10 identified subregions of the UIB, and the spatially (field-) significant climatic trends are then qualitatively compared with the trends in discharge out of corresponding subregions. Over the recent period (1995-2012), we find warming and drying of spring (field-significant in March) and increasing early melt season discharge from most of the subregions, likely due to a rapid snowmelt. In stark contrast, most of the subregions feature a field-significant cooling within the monsoon period (particularly in July and September), which coincides well with the main glacier melt season. Hence, a decreasing or weakly increasing discharge is observed from the corresponding subregions during mid- to late melt season (particularly in July). Such tendencies, being largely consistent with the long-term trends (1961-2012), most likely indicate dominance of the nival but suppression of the glacial melt regime, altering overall hydrology of the UIB in

  4. Warming Trends and Bleaching Stress of the World’s Coral Reefs 1985–2012

    Science.gov (United States)

    Heron, Scott F.; Maynard, Jeffrey A.; van Hooidonk, Ruben; Eakin, C. Mark

    2016-01-01

    Coral reefs across the world’s oceans are in the midst of the longest bleaching event on record (from 2014 to at least 2016). As many of the world’s reefs are remote, there is limited information on how past thermal conditions have influenced reef composition and current stress responses. Using satellite temperature data for 1985–2012, the analysis we present is the first to quantify, for global reef locations, spatial variations in warming trends, thermal stress events and temperature variability at reef-scale (~4 km). Among over 60,000 reef pixels globally, 97% show positive SST trends during the study period with 60% warming significantly. Annual trends exceeded summertime trends at most locations. This indicates that the period of summer-like temperatures has become longer through the record, with a corresponding shortening of the ‘winter’ reprieve from warm temperatures. The frequency of bleaching-level thermal stress increased three-fold between 1985–91 and 2006–12 – a trend climate model projections suggest will continue. The thermal history data products developed enable needed studies relating thermal history to bleaching resistance and community composition. Such analyses can help identify reefs more resilient to thermal stress. PMID:27922080

  5. On the Nature of Trends

    DEFF Research Database (Denmark)

    Mackinney-Valentin, Maria

    2010-01-01

    A consolidation of the field Trend Studies through mapping, updating and developing trend theory.......A consolidation of the field Trend Studies through mapping, updating and developing trend theory....

  6. Eye and Hand Movements during Reconstruction of Spatial Memory

    Directory of Open Access Journals (Sweden)

    Melanie Rose Burke

    2012-05-01

    Full Text Available Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (eg, Awh et al 2006, Trends in Cognitive Sciences 10, 124–130. This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change from an array presented either simultaneously or sequentially. The time delay between target presentation and recall (0, 5, or 10s and the number of locations to be remembered (2–5 were also manipulated. Analysis of the response phase revealed subjects were less accurate (touch data and fixated longer (eye data when responding to sequentially presented targets. Fixation duration was also influenced by whether spatial location was initially signalled by colour or shape change. We conclude that attention and temporal delays during retention of a target play a minor role in motor behaviour during a corsi spatial memory task. In contrast, the type of memory required (ie, location and/or memory and number of items plays a key role on subject performance and behaviour.

  7. Spatio-temporal trends and risk factors for Shigella from 2001 to 2011 in Jiangsu Province, People's Republic of China.

    Science.gov (United States)

    Tang, Fenyang; Cheng, Yuejia; Bao, Changjun; Hu, Jianli; Liu, Wendong; Liang, Qi; Wu, Ying; Norris, Jessie; Peng, Zhihang; Yu, Rongbin; Shen, Hongbing; Chen, Feng

    2014-01-01

    This study aimed to describe the spatial and temporal trends of Shigella incidence rates in Jiangsu Province, People's Republic of China. It also intended to explore complex risk modes facilitating Shigella transmission. County-level incidence rates were obtained for analysis using geographic information system (GIS) tools. Trend surface and incidence maps were established to describe geographic distributions. Spatio-temporal cluster analysis and autocorrelation analysis were used for detecting clusters. Based on the number of monthly Shigella cases, an autoregressive integrated moving average (ARIMA) model successfully established a time series model. A spatial correlation analysis and a case-control study were conducted to identify risk factors contributing to Shigella transmissions. The far southwestern and northwestern areas of Jiangsu were the most infected. A cluster was detected in southwestern Jiangsu (LLR = 11674.74, PHighways and water sources potentially caused spatial variation in Shigella development in Jiangsu. The case-control study confirmed not washing hands before dinner (OR = 3.64) and not having access to a safe water source (OR = 2.04) as the main causes of Shigella in Jiangsu Province. Improvement of sanitation and hygiene should be strengthened in economically developed counties, while access to a safe water supply in impoverished areas should be increased at the same time.

  8. Towards understanding temporal and spatial dynamics of seagrass landscapes using time-series remote sensing

    Science.gov (United States)

    Lyons, Mitchell B.; Roelfsema, Chris M.; Phinn, Stuart R.

    2013-03-01

    The spatial and temporal dynamics of seagrasses have been well studied at the leaf to patch scales, however, the link to large spatial extent landscape and population dynamics is still unresolved in seagrass ecology. Traditional remote sensing approaches have lacked the temporal resolution and consistency to appropriately address this issue. This study uses two high temporal resolution time-series of thematic seagrass cover maps to examine the spatial and temporal dynamics of seagrass at both an inter- and intra-annual time scales, one of the first globally to do so at this scale. Previous work by the authors developed an object-based approach to map seagrass cover level distribution from a long term archive of Landsat TM and ETM+ images on the Eastern Banks (≈200 km2), Moreton Bay, Australia. In this work a range of trend and time-series analysis methods are demonstrated for a time-series of 23 annual maps from 1988 to 2010 and a time-series of 16 monthly maps during 2008-2010. Significant new insight was presented regarding the inter- and intra-annual dynamics of seagrass persistence over time, seagrass cover level variability, seagrass cover level trajectory, and change in area of seagrass and cover levels over time. Overall we found that there was no significant decline in total seagrass area on the Eastern Banks, but there was a significant decline in seagrass cover level condition. A case study of two smaller communities within the Eastern Banks that experienced a decline in both overall seagrass area and condition are examined in detail, highlighting possible differences in environmental and process drivers. We demonstrate how trend and time-series analysis enabled seagrass distribution to be appropriately assessed in context of its spatial and temporal history and provides the ability to not only quantify change, but also describe the type of change. We also demonstrate the potential use of time-series analysis products to investigate seagrass growth and

  9. Key Directions of Sectoral and Spatial Changes in the Russian Industry

    Directory of Open Access Journals (Sweden)

    Chasovsky Vladimir

    2015-09-01

    Full Text Available This article considers major trends in the spatial and sectoral structure of national production and analyses the patterns of transformation of industrial systems into integrated industrial complexes, which show higher efficiency in transit condiétions. The author presents a new approach to studying the structural transformation of industrial systems during the transition of the national economy, which will make it possible to identify major trends in national production. The article seeks to draw attention to the methodology of developing and implementing industrial policy and devising an algorithm of effective transition of Russian industries in the modern conditions of international division of labor. The modernization and transnationalization of national production rests on a number of methods that make it possible for the corporate management to react rapidly to changes in the global market situation. These methods include strategic segmentation, analyzing the ability to adapt to the expected conditions, devising a company’s entrepreneurial strategy, and changes in the spatial and industrial structure of production. The transformation of national industry is associated with the introduction of mechanisms of industrial integration structures using single organizational production modules capable of rational combination and transformation of the elements of national production structure to create competitive transnational production associations, such as clusters and other production forms serving as ‘growth poles’ and becoming elements of the emerging framework for national production. This methodology makes it possible to develop new approaches, methods, and principles for analyzing the transformation of the national spatial and industrial system during economic transition. Current factors, features, patterns and trends in the transformation of national industrial systems are identified; a mechanism for devising and implementing a

  10. Assessing satellite-based start-of-season trends in the US High Plains

    International Nuclear Information System (INIS)

    Lin, X; Sassenrath, G F; Hubbard, K G; Mahmood, R

    2014-01-01

    To adequately assess the effects of global warming it is necessary to address trends and impacts at the local level. This study examines phenological changes in the start-of-season (SOS) derived from satellite observations from 1982–2008 in the US High Plains region. The surface climate-based SOS was also evaluated. The averaged profiles of SOS from 37° to 49°N latitude by satellite- and climate-based methods were in reasonable agreement, especially for areas where croplands were masked out and an additional frost date threshold was adopted. The statistically significant trends of satellite-based SOS show a later spring arrival ranging from 0.1 to 4.9 days decade −1 over nine Level III ecoregions. We found the croplands generally exhibited larger trends (later arrival) than the non-croplands. The area-averaged satellite-based SOS for non-croplands (i.e. mostly grasslands) showed no significant trends. We examined the trends of temperatures, precipitation, and standardized precipitation index (SPI), as well as the strength of correlation between the satellite-based SOS and these climatic drivers. Our results indicate that satellite-based SOS trends are spatially and primarily related to annual maximum normalized difference vegetation index (NDVI, mostly in summertime) and/or annual minimum NDVI (mostly in wintertime) and these trends showed the best correlation with six-month SPI over the period 1982–2008 in the US High Plains region. (letter)

  11. Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

    Science.gov (United States)

    Jiao, L. M.; Tang, X.; Liu, X. P.

    2017-09-01

    Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  12. Global trends in satellite-based emergency mapping

    Science.gov (United States)

    Voigt, Stefan; Giulio-Tonolo, Fabio; Lyons, Josh; Kučera, Jan; Jones, Brenda; Schneiderhan, Tobias; Platzeck, Gabriel; Kaku, Kazuya; Hazarika, Manzul Kumar; Czaran, Lorant; Li, Suju; Pedersen, Wendi; James, Godstime Kadiri; Proy, Catherine; Muthike, Denis Macharia; Bequignon, Jerome; Guha-Sapir, Debarati

    2016-01-01

    Over the past 15 years, scientists and disaster responders have increasingly used satellite-based Earth observations for global rapid assessment of disaster situations. We review global trends in satellite rapid response and emergency mapping from 2000 to 2014, analyzing more than 1000 incidents in which satellite monitoring was used for assessing major disaster situations. We provide a synthesis of spatial patterns and temporal trends in global satellite emergency mapping efforts and show that satellite-based emergency mapping is most intensively deployed in Asia and Europe and follows well the geographic, physical, and temporal distributions of global natural disasters. We present an outlook on the future use of Earth observation technology for disaster response and mitigation by putting past and current developments into context and perspective.

  13. Extreme Drought-induced Trend Changes in MODIS EVI Time Series in Yunnan, China

    International Nuclear Information System (INIS)

    Huang, Kaicheng; Zhou, Tao; Zhao, Xiang

    2014-01-01

    Extreme climatic events triggered by global climate change are expected to increase significantly hence research into vegetation response is crucial to evaluate environmental risk. Yunnan province, locating in southwest China, experienced an extreme drought event (from autumn of 2009 to spring of 2010), with the lowest percentage rainfall anomaly and the longest non-rain days in the past 50 years. This study aimed to explore the characteristics and differences in the response to drought of four land cover types in Yunnan province, including forest, grassland, shrub, and cropland during the period 2001-2011. We used remote sensing data, MODIS-derived EVI (Enhanced Vegetation Index) to study the vegetation responses to this extreme drought event. The EVI time series were decomposed into trend, seasonal and remainder components using BFAST (Breaks For Additive Seasonal and Trend) which accounts for seasonality and enables the detection of trend changes within the time series. The preliminary results showed that: (1) BFAST proved to be capable of detecting drought-induced trend changes in EVI time series. (2) Changes in the trend component over time consisted of both gradual and abrupt changes. (3) Different spatial patterns were found for abrupt and gradual changes. (4) Cropland exhibited an abrupt change, due to its sensitivity to severe drought, while the forest seemed least affected by the extreme drought

  14. Trends into rainfall time series of two andes basins of Valle del Cauca (Colombia

    Directory of Open Access Journals (Sweden)

    Faisury Cardona-Guerrero

    2014-01-01

    Full Text Available With the goal of detecting changes or trends in registered data of daily rainfall in the basins of rivers Dagua and Cali, located in the south-west of Colombia, in the Valle del Cauca, nine climate extremes indices were calculated using the RClimDex software. For this, precipitation trends were analyzed in 18 rain gauges located in the study area with historical series ranging between 21 and 56 years. Homogeneity tests were made to data to ensure consistency in the information. The results show changes in rainfall, dominated by the increasing trends for almost all indices; however most of the trends do not show high statistical significance. Also, a significant increase in the average annual total rainfall of 15.2 mm (Dagua river basin and 9.1 mm (Cali river basin in the stations located below 1500 msnm was obtained. Moreover, in the stations located at higher elevations, decreases were observed. There is a homogeneous spatial distribution for the most of the indices and similar patterns were found located in defined areas of the study zone, which may affect the runoff production in watersheds in the coming years.

  15. Study of spatial resolution in three-dimensional rotational angiography

    International Nuclear Information System (INIS)

    Enoki, Takuya; Nasada, Toshiya; Matsumoto, Kazuma; Umehara, Takayoshi

    2006-01-01

    In interventional radiology (IVR) of cerebral aneurysms, it is important to understand the form and physical relationships between the cerebral aneurysm and the surrounding vessels. However, because the vessels in the head area are highly complex, it can be difficult to comprehend the structure using conventional angiography. Therefore, three-dimensional rotational angiography (3D-RA) has been used in recent years. This article discusses studies of the spatial resolution of 3D-RA. We reconstructed 3D-RA of an acrylic slit phantom (slit widths: 0.5, 0.75, 1.0, 1.5 mm) and examined spatial resolution by visual evaluation and profile curves. When the slit phantom was arranged to avoid the effect of beam hardening, the spatial resolution of 3D-RA was found to be as high as 0.75 mm. When the slit phantom was placed orthogonal to the rotational axis of the C-arm, the spatial resolution of 3D-RA was decreased because of the cone angle effect of X-rays. However, it was considered within the allowable range for clinical study. Consequently, 3D-RA is valuable in IVR. (author)

  16. Performance of some biotic indices in the real variable world: A case study at different spatial scales in North-Western Mediterranean Sea

    International Nuclear Information System (INIS)

    Tataranni, Mariella; Lardicci, Claudio

    2010-01-01

    The aim of this study was to analyse the variability of four different benthic biotic indices (AMBI, BENTIX, H', M-AMBI) in two marine coastal areas of the North-Western Mediterranean Sea. In each coastal area, 36 replicates were randomly selected according to a hierarchical sampling design, which allowed estimating the variance components of the indices associated with four different spatial scales (ranging from metres to kilometres). All the analyses were performed at two different sampling periods in order to evaluate if the observed trends were consistent over the time. The variance components of the four indices revealed complex trends and different patterns in the two sampling periods. These results highlighted that independently from the employed index, a rigorous and appropriate sampling design taking into account different scales should always be used in order to avoid erroneous classifications and to develop effective monitoring programs. - How heterogeneous distribution of macrobenthos can affect the performance of some biotic indices.

  17. Exploring spatial patterns and hotspots of diarrhea in Chiang Mai, Thailand

    Directory of Open Access Journals (Sweden)

    Tripathi Nitin K

    2009-06-01

    Full Text Available Abstract Background Diarrhea is a major public health problem in Thailand. The Ministry of Public Health, Thailand, has been trying to monitor and control this disease for many years. The methodology and the results from this study could be useful for public health officers to develop a system to monitor and prevent diarrhea outbreaks. Methods The objective of this study was to analyse the epidemic outbreak patterns of diarrhea in Chiang Mai province, Northern Thailand, in terms of their geographical distributions and hotspot identification. The data of patients with diarrhea at village level and the 2001–2006 population censuses were collected to achieve the objective. Spatial analysis, using geographic information systems (GIS and other methods, was used to uncover the hidden phenomena from the data. In the data analysis section, spatial statistics such as quadrant analysis (QA, nearest neighbour analysis (NNA, and spatial autocorrelation analysis (SAA, were used to identify the spatial patterns of diarrhea in Chiang Mai province. In addition, local indicators of spatial association (LISA and kernel density (KD estimation were used to detect diarrhea hotspots using data at village level. Results The hotspot maps produced by the LISA and KD techniques showed spatial trend patterns of diarrhea diffusion. Villages in the middle and northern regions revealed higher incidences. Also, the spatial patterns of diarrhea during the years 2001 and 2006 were found to represent spatially clustered patterns, both at global and local scales. Conclusion Spatial analysis methods in GIS revealed the spatial patterns and hotspots of diarrhea in Chiang Mai province from the year 2001 to 2006. To implement specific and geographically appropriate public health risk-reduction programs, the use of such spatial analysis tools may become an integral component in the epidemiologic description, analysis, and risk assessment of diarrhea.

  18. Determining New Trends with Regard to the Studies in Curricula and Instruction Field

    Science.gov (United States)

    Hursen, Cigdem; Koruroglu, Ayten; Bahali, Sultan; Mercan, Naziyet

    2016-01-01

    The aim of this study is to determine the new trends concerning curricula and instruction. The articles that are published in journals of SSCI and ERIC databases are taken into the scope of this study. The new trends regarding relevant literature are tried to be identified by analysing 3079 articles in total through the content analysis method.…

  19. Spatial and Temporal Variability of Rainfall over the South-West Coast of Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Sarwar Hossain

    2014-04-01

    Full Text Available This study examined the spatial and temporal rainfall variability from the 1940s to 2007 in the south west coastal region of Bangladesh. Time series statistical tests were applied to examine the spatial and temporal trends in three time segments (1948–1970, 1971–1990 and 1991–2007 and four seasons (Pre-monsoon; Monsoon; Post-Monsoon and Winter, during the period 1948–2007. Eight weather stations were divided into two zones: exposed (exposed to sea and interior (distant to sea. Overall, rainfall increased during the period 1948–2007, while the trends intensified during post-1990s. Post-monsoon and winter rainfall was observed to follow significant positive trends at most weather stations during the time period 1948–2007. The rate of change was found in exposed zone and interior zone are +12.51 and +4.86 mm/year, respectively, over post monsoon and +0.9 and +1.86 mm/year, respectively, over winter. These trends intensified both in the exposed zone (+45.81 mm/year and the interior zone (+27.09 mm/year 1990 onwards. Winter rainfall does not exhibit significant change (p > 0.1 over the exterior or interior zone, though individual stations like Jessore, Satkhira and Bhola show significant negative trends after 1990s. Although the trends were observed to weaken in the monsoon and pre-monsoon seasons, they are not significant. Moreover, an 11-year cyclicity was found within these two seasons, whilst no cyclicity was observed in the post-monsoon and winter seasons. Sequential Mann Kendal test reveals that the changes in two zones rainfall trends are started around mid-80s, where step change found only for fours season in Khulna stations and also for winter seasons in all weather stations. These changes may have a detrimental effect on rain-fed agriculture in Bangladesh. The application of palaeo-environmental techniques, threshold determination and rainfall analysis across the whole country could be useful to support adaptation planning of

  20. A Study of the Groundwater Level Spatial Variability in the Messara Valley of Crete

    Science.gov (United States)

    Varouchakis, E. A.; Hristopulos, D. T.; Karatzas, G. P.

    2009-04-01

    trend model was constructed that accounted for the distance of the wells from the river bed. The spatial dependence of the fluctuations was studied by fitting isotropic and anisotropic empirical variograms with classical models, the Matérn model and the Spartan variogram family (Hristopulos, 2003; Hristopoulos and Elogne, 2007). The most accurate results, mean absolute prediction error of 4.57 masl, were obtained using the modified Box-Cox transform of the original data. The exponential and the isotropic Spartan variograms provided the best fits to the experimental variogram. Using Ordinary Kriging with either variogram function gave a mean absolute estimation error of 4.57 masl based on leave-one-out cross validation. The bias error of the predictions was calculated equal to -0.38 masl and the correlation coefficient of the predictions with respect of the original data equal to 0.8. The estimates located on the borders of the study domain presented a higher prediction error that varies from 8 to 14 masl due to the limited number of neighbor data. The maximum estimation error, observed at the extreme low value calculation, was 23 masl. The method of locally weighted regression (LWR), (NIST/SEMATECH 2009) was also investigated as an alternative approach for spatial modeling. The trend calculated from a second order LWR method showed a remarkable fit to the original data marked by a mean absolute estimation error of 4.4 masl. The bias prediction error was calculated equal to -0.16 masl and the correlation coefficient between predicted and original data equal to 0.88 masl. Higher estimation errors were found at the same locations and vary within the same range. The extreme low value calculation error has improved to 21 masl. Plans for future research include the incorporation of spatial anisotropy in the kriging algorithm, the investigation of kernel functions other than the tricube in LWR, as well as the use of locally adapted bandwidth values. Furthermore, pumping rates

  1. Mobile Air Monitoring Data Processing Strategies and Effects on Spatial Air Pollution Trends

    Science.gov (United States)

    The collection of real-time air quality measurements while in motion (i.e., mobile monitoring) is currently conducted worldwide to evaluate in situ emissions, local air quality trends, and air pollutant exposure. This measurement strategy pushes the limits of traditional data an...

  2. Evaluation of reported NOx emission trends between 2005 and 2013 by assimilation of OMI-NO2 data into LOTOS-EUROS

    Science.gov (United States)

    Schaap, Martijn; Segers, Arjo; Curier, Lyana; Timmermans, Renske

    2016-04-01

    Consistent and long time series of remotely sensed trace gas levels may provide a useful tool to estimate surface emissions and emission trends. We use the OMI-NO2 product in conjunction with the LOTOS-EUROS CTM to estimate European emission trends through correction of the OMI-time series for meteorological variability as well as through assimilation using an ensemble kalman filter system (EnKF). The chemistry transport model captures a large fraction of the variability in NO2 columns at a synoptic timescale, although a seasonal signal in the bias between the modeled and retrieved column data remains. Prior to the assimilation, the OMI-NO2 data have been analyzed to establish the spatially variable temporal and spatial correlation lengths, required for the settings in the EnKF system. The assimilation run for 2005-2013 was performed using constant 2005 emissions to be able to quantify the emission change. The assimilation reduces the model-observation differences considerably. Significant negative trends of 2-3 % per year (as compared to 2005) were found in highly industrialized areas across Western Europe. The assimilation system also identifies the areas with major emission reductions in e.g. northern Spain as identified in earlier studies. Comparison of the trends derived from the assimilation and the data itself shows a high level of agreement, both the trends found in this way are smaller than those reported.

  3. Case studies in intelligent computing achievements and trends

    CERN Document Server

    Issac, Biju

    2014-01-01

    Although the field of intelligent systems has grown rapidly in recent years, there has been a need for a book that supplies a timely and accessible understanding of this important technology. Filling this need, Case Studies in Intelligent Computing: Achievements and Trends provides an up-to-date introduction to intelligent systems.This edited book captures the state of the art in intelligent computing research through case studies that examine recent developments, developmental tools, programming, and approaches related to artificial intelligence (AI). The case studies illustrate successful ma

  4. Spatial normalization of array-CGH data

    Directory of Open Access Journals (Sweden)

    Brennetot Caroline

    2006-05-01

    Full Text Available Abstract Background Array-based comparative genomic hybridization (array-CGH is a recently developed technique for analyzing changes in DNA copy number. As in all microarray analyses, normalization is required to correct for experimental artifacts while preserving the true biological signal. We investigated various sources of systematic variation in array-CGH data and identified two distinct types of spatial effect of no biological relevance as the predominant experimental artifacts: continuous spatial gradients and local spatial bias. Local spatial bias affects a large proportion of arrays, and has not previously been considered in array-CGH experiments. Results We show that existing normalization techniques do not correct these spatial effects properly. We therefore developed an automatic method for the spatial normalization of array-CGH data. This method makes it possible to delineate and to eliminate and/or correct areas affected by spatial bias. It is based on the combination of a spatial segmentation algorithm called NEM (Neighborhood Expectation Maximization and spatial trend estimation. We defined quality criteria for array-CGH data, demonstrating significant improvements in data quality with our method for three data sets coming from two different platforms (198, 175 and 26 BAC-arrays. Conclusion We have designed an automatic algorithm for the spatial normalization of BAC CGH-array data, preventing the misinterpretation of experimental artifacts as biologically relevant outliers in the genomic profile. This algorithm is implemented in the R package MANOR (Micro-Array NORmalization, which is described at http://bioinfo.curie.fr/projects/manor and available from the Bioconductor site http://www.bioconductor.org. It can also be tested on the CAPweb bioinformatics platform at http://bioinfo.curie.fr/CAPweb.

  5. Quantitative assessment of industrial VOC emissions in China: Historical trend, spatial distribution, uncertainties, and projection

    Science.gov (United States)

    Zheng, Chenghang; Shen, Jiali; Zhang, Yongxin; Huang, Weiwei; Zhu, Xinbo; Wu, Xuecheng; Chen, Linghong; Gao, Xiang; Cen, Kefa

    2017-02-01

    The temporal trends of industrial volatile organic compound (VOC) emissions was comprehensively summarized for the 2011 to 2013 period, and the projections for 2020 to 2050 for China were set. The results demonstrate that industrial VOC emissions in China increased from 15.3 Tg in 2011 to 29.4 Tg in 2013 at an annual average growth rate of 38.3%. Guangdong (3.45 Tg), Shandong (2.85 Tg), and Jiangsu (2.62 Tg) were the three largest contributors collectively accounting for 30.4% of the national total emissions in 2013. The top three average industrial VOC emissions per square kilometer were Shanghai (247.2 ton/km2), Tianjin (62.8 ton/km2), and Beijing (38.4 ton/km2), which were 12-80 times of the average level in China. The data from the inventory indicate that the use of VOC-containing products, as well as the production and use of VOCs as raw materials, as well as for storage and transportation contributed 75.4%, 10.3%, 9.1%, and 5.2% of the total emissions, respectively. ArcGIS was used to display the remarkable spatial distribution variation by allocating the emission into 1 km × 1 km grid cells with a population as surrogate indexes. Combined with future economic development and population change, as well as implementation of policy and upgrade of control technologies, three scenarios (scenarios A, B, and C) were set to project industrial VOC emissions for the years 2020, 2030, and 2050, which present the industrial VOC emissions in different scenarios and the potential of reducing emissions. Finally, the result shows that the collaborative control policies considerably influenced industrial VOC emissions.

  6. 0.1 Trend analysis of δ18O composition of precipitation in Germany: Combining Mann-Kendall trend test and ARIMA models to correct for higher order serial correlation

    Science.gov (United States)

    Klaus, Julian; Pan Chun, Kwok; Stumpp, Christine

    2015-04-01

    Spatio-temporal dynamics of stable oxygen (18O) and hydrogen (2H) isotopes in precipitation can be used as proxies for changing hydro-meteorological and regional and global climate patterns. While spatial patterns and distributions gained much attention in recent years the temporal trends in stable isotope time series are rarely investigated and our understanding of them is still limited. These might be a result of a lack of proper trend detection tools and effort for exploring trend processes. Here we make use of an extensive data set of stable isotope in German precipitation. In this study we investigate temporal trends of δ18O in precipitation at 17 observation station in Germany between 1978 and 2009. For that we test different approaches for proper trend detection, accounting for first and higher order serial correlation. We test if significant trends in the isotope time series based on different models can be observed. We apply the Mann-Kendall trend tests on the isotope series, using general multiplicative seasonal autoregressive integrate moving average (ARIMA) models which account for first and higher order serial correlations. With the approach we can also account for the effects of temperature, precipitation amount on the trend. Further we investigate the role of geographic parameters on isotope trends. To benchmark our proposed approach, the ARIMA results are compared to a trend-free prewhiting (TFPW) procedure, the state of the art method for removing the first order autocorrelation in environmental trend studies. Moreover, we explore whether higher order serial correlations in isotope series affects our trend results. The results show that three out of the 17 stations have significant changes when higher order autocorrelation are adjusted, and four stations show a significant trend when temperature and precipitation effects are considered. Significant trends in the isotope time series are generally observed at low elevation stations (≤315 m a

  7. Historical spatial reconstruction of a spawning-aggregation fishery.

    Science.gov (United States)

    Buckley, Sarah M; Thurstan, Ruth H; Tobin, Andrew; Pandolfi, John M

    2017-12-01

    Aggregations of individual animals that form for breeding purposes are a critical ecological process for many species, yet these aggregations are inherently vulnerable to exploitation. Studies of the decline of exploited populations that form breeding aggregations tend to focus on catch rate and thus often overlook reductions in geographic range. We tested the hypothesis that catch rate and site occupancy of exploited fish-spawning aggregations (FSAs) decline in synchrony over time. We used the Spanish mackerel (Scomberomorus commerson) spawning-aggregation fishery in the Great Barrier Reef as a case study. Data were compiled from historical newspaper archives, fisher knowledge, and contemporary fishery logbooks to reconstruct catch rates and exploitation trends from the inception of the fishery. Our fine-scale analysis of catch and effort data spanned 103 years (1911-2013) and revealed a spatial expansion of fishing effort. Effort shifted offshore at a rate of 9.4 nm/decade, and 2.9 newly targeted FSAs were reported/decade. Spatial expansion of effort masked the sequential exploitation, commercial extinction, and loss of 70% of exploited FSAs. After standardizing for improvements in technological innovations, average catch rates declined by 90.5% from 1934 to 2011 (from 119.4 to 11.41 fish/vessel/trip). Mean catch rate of Spanish mackerel and occupancy of exploited mackerel FSAs were not significantly related. Our study revealed a special kind of shifting spatial baseline in which a contraction in exploited FSAs occurred undetected. Knowledge of temporally and spatially explicit information on FSAs can be relevant for the conservation and management of FSA species. © 2017 Society for Conservation Biology.

  8. ANALYSIS OF SPATIAL PATTERN AND INFLUENCING FACTORS OF E-COMMERCE

    OpenAIRE

    Y. Zhang; J. Chen; S. Zhang

    2017-01-01

    This paper aims to study the relationship between e-commerce development and geographical characteristics using data of e-commerce, economy, Internet, express delivery and population from 2011 to 2015. Moran’s I model and GWR model are applied to analyze the spatial pattern of E-commerce and its influencing factors. There is a growth trend of e-commerce from west to east, and it is obvious to see that e-commerce development has a space-time clustering, especially around the Yangtze R...

  9. Spatially Resolved Isotopic Source Signatures of Wetland Methane Emissions

    Science.gov (United States)

    Ganesan, A. L.; Stell, A. C.; Gedney, N.; Comyn-Platt, E.; Hayman, G.; Rigby, M.; Poulter, B.; Hornibrook, E. R. C.

    2018-04-01

    We present the first spatially resolved wetland δ13C(CH4) source signature map based on data characterizing wetland ecosystems and demonstrate good agreement with wetland signatures derived from atmospheric observations. The source signature map resolves a latitudinal difference of 10‰ between northern high-latitude (mean -67.8‰) and tropical (mean -56.7‰) wetlands and shows significant regional variations on top of the latitudinal gradient. We assess the errors in inverse modeling studies aiming to separate CH4 sources and sinks by comparing atmospheric δ13C(CH4) derived using our spatially resolved map against the common assumption of globally uniform wetland δ13C(CH4) signature. We find a larger interhemispheric gradient, a larger high-latitude seasonal cycle, and smaller trend over the period 2000-2012. The implication is that erroneous CH4 fluxes would be derived to compensate for the biases imposed by not utilizing spatially resolved signatures for the largest source of CH4 emissions. These biases are significant when compared to the size of observed signals.

  10. Current trends in Bayesian methodology with applications

    CERN Document Server

    Upadhyay, Satyanshu K; Dey, Dipak K; Loganathan, Appaia

    2015-01-01

    Collecting Bayesian material scattered throughout the literature, Current Trends in Bayesian Methodology with Applications examines the latest methodological and applied aspects of Bayesian statistics. The book covers biostatistics, econometrics, reliability and risk analysis, spatial statistics, image analysis, shape analysis, Bayesian computation, clustering, uncertainty assessment, high-energy astrophysics, neural networking, fuzzy information, objective Bayesian methodologies, empirical Bayes methods, small area estimation, and many more topics.Each chapter is self-contained and focuses on

  11. Spatial and verbal working memory: A functional magnetic resonance imaging study

    Directory of Open Access Journals (Sweden)

    Blaž Koritnik

    2004-08-01

    Full Text Available According to numerous studies, working memory is not a unitary system. Baddeley's model of working memory includes besides central executive also two separate systems for verbal and visuo-spatial information processing. A modality- and process-specific specialization presumably exists in working memory system of the frontal lobes. In our preliminary study, we have used functional magnetic resonance imaging to study the pattern of cortical activation during spatial and verbal n-back task in six healthy subjects. A bilateral fronto-parietal cortical network was activated in both tasks. There was larger activation of right parietal and bilateral occipital areas in spatial than in vebal task. Activation of left sensorimotor area was larger in verbal compared to spatial task. No task-specific differences were found in the prefrontal cortex. Our results support the assumption that modality-specific processes exist within the working-memory system.

  12. Secular trends in monthly heating and cooling demands in Croatia

    Science.gov (United States)

    Cvitan, Lidija; Sokol Jurković, Renata

    2016-08-01

    This paper analyzes long-term heating and cooling trends for five locations in Croatia from 1901 to 2008 to assist in the revision of Croatia's heating and cooling energy policy. Trends in monthly heating degree-days (HDD) and cooling degree-days (CDD) were determined for three related temperature threshold values each and analyzed to provide insight into the influence of desired thermal comfort on the extent of changes in energy consumption. Monthly trends in the corresponding number of heating days (HD) and cooling days (CD) were also analyzed. A basic investigation of HDD, HD, CDD, and CD trends proved to be essential to the development of a complete description of important climate-related conditions that impact energy demands associated with heating and cooling. In a few cases, the dependence of the trends on the implemented temperature thresholds was rather pronounced and was reflected in great spatial and temporal variations in monthly trends. The statistical significance of the detected monthly trends illustrated a diverse range of possible impacts of climate changes on heating and cooling energy consumption both across and within three main climate regions in Croatia (continental, mountainous, and maritime). It is confirmed that the applied monthly scale for analyses is suitable for assessing heating and cooling practices.

  13. How noise and coupling influence leading indicators of population extinction in a spatially extended ecological system.

    Science.gov (United States)

    O'Regan, Suzanne M

    2018-12-01

    Anticipating critical transitions in spatially extended systems is a key topic of interest to ecologists. Gradually declining metapopulations are an important example of a spatially extended biological system that may exhibit a critical transition. Theory for spatially extended systems approaching extinction that accounts for environmental stochasticity and coupling is currently lacking. Here, we develop spatially implicit two-patch models with additive and multiplicative forms of environmental stochasticity that are slowly forced through population collapse, through changing environmental conditions. We derive patch-specific expressions for candidate indicators of extinction and test their performance via a simulation study. Coupling and spatial heterogeneities decrease the magnitude of the proposed indicators in coupled populations relative to isolated populations, and the noise regime and the degree of coupling together determine trends in summary statistics. This theory may be readily applied to other spatially extended ecological systems, such as coupled infectious disease systems on the verge of elimination.

  14. Encouraging Spatial Talk: Using Children's Museums to Bolster Spatial Reasoning

    Science.gov (United States)

    Polinsky, Naomi; Perez, Jasmin; Grehl, Mora; McCrink, Koleen

    2017-01-01

    Longitudinal spatial language intervention studies have shown that greater exposure to spatial language improves children's performance on spatial tasks. Can short naturalistic, spatial language interactions also evoke improved spatial performance? In this study, parents were asked to interact with their child at a block wall exhibit in a…

  15. Understanding Evapotranspiration Trends and their Driving Mechanisms: An investigation across CONUS based on numerical modeling

    Science.gov (United States)

    Parr, D.; Wang, G.; Fu, C.

    2015-12-01

    As shown by climate models, increasing global temperatures and enhanced greenhouse gas concentration such as CO2 have had major effects on the dynamics of the hydrologic cycle and the surface energy budget, in particular, on evapotranspiration (ET). ET has significant decadal variations whether it be regionally or globally and variations of ET have major environmental and socioeconomic impacts. A number of recent studies have found a global increase in annual mean ET around 7mm per year per decade from about 1982 to the late 1990s. These results correspond with what is expected from an intensification of the hydrological cycle. However, the increasing ET trend did not continue after 1998 and from 1998-2008 this global trend was replaced with a decreasing trend of similar magnitude. This study uses numerical modeling to investigate if similar changing ET trends emerge in the continental U.S and part of northern Mexico. After validating model simulated evaporative fluxes and comparing spatial patterns to the aforementioned studies, various changing trends of different signs are identified across the U.S., and specific regions with strong signals of change are chosen for further examination with the purpose of identifying the root causes of these changing trends and which variables are most influential towards change. Experimental simulations conducted to isolate the most influential factors towards ET reveal that precipitation amount as well as its characteristics have the greatest impact on the ET trends discovered, with other factors like wind and air temperatures displaying less influence over inter-annual trends. This study helps better understand terrestrial ET and it's interactions which will help facilitate better predictions of change in surface climate such as heatwaves and droughts as well as impacts on water resources.

  16. Household size and urban spatial change: end of an era?

    Directory of Open Access Journals (Sweden)

    Robert Sinclair

    2004-12-01

    Full Text Available A dominant demographic trend of the last few decades has been the declining size of house-holds in Western industrialized countries. Following closely upon the Baby Boom, the development became a major topic of discussion for almost two decades. The basis for, and consequences of, these changes have been well covered in the demographic literature, but their spatial implications have received less attention. Yet the, phenomenon has had a pro-found spatial impact at every level of the urban system. Recent statistics indicate that house-hold size continues to decline, but does so at a rapidly decreasing rate. The present paper considers the spatial repercussions of this trend. More specifically, the paper has three aims. (1 The paper summarizes and puts into present-day perspective, a volume of research con-ducted a decade ago upon the spatial impact of declining household size upon the U.S. urban system (Sinclair, 1991. (2 Considers more recent demographic developments, ask-ing whether the impact of declining household size upon the urban system is declining or coming to a close, (3 Considers other demographic developments which might he taking the place of declining household size in driving the urban system. In sum, the paper at-tempts to answer the question. Is an era, which has signifycantly impacted the U.S. urban system, coming to a close?

  17. Trends in atmospheric deposition fluxes of sulphur and nitrogen in Czech forests

    International Nuclear Information System (INIS)

    Hůnová, Iva; Maznová, Jana; Kurfürst, Pavel

    2014-01-01

    We present the temporal trends and spatial changes of deposition of sulphur and nitrogen in Czech forests based on records from long-term monitoring. A statistically significant trend for sulphur was detected at most of the sites measuring for wet, dry, and total deposition fluxes and at many of these the trend was also present for the period after 2000. The spatial pattern of the changes in sulphur deposition flux between 1995 and 2011 shows the decrease over the entire forested area in a wide range of 18.1–0.2 g m −2 year −1 with the most pronounced improvement in formerly most impacted regions. Nitrogen still represents a considerable stress in many areas. The value of nitrogen deposition flux of 1 g m −2 year −1 is exceeded over a significant portion of the country. On an equivalent basis, the ion ratios of NO 3 − /SO 4 2− and NH 4 + /SO 4 2− in precipitation show significantly increasing trends in time similarly to those of pH. -- Highlights: • Significant decrease of sulphur deposition at most of sites has been recorded. • Nitrogen deposition still represents a considerable stress in Czech forests. • Significantly increasing trends of NO 3 − /SO 4 2− , NH 4 + /SO 4 2− , and pH in precipitation. -- While sulphur deposition significantly decreased with the highest improvement in formerly most affected areas, nitrogen deposition still represents a considerable stress in Czech forests

  18. Trend analysis of evapotranspiration over India: Observed from long-term satellite measurements

    Science.gov (United States)

    Goroshi, Sheshakumar; Pradhan, Rohit; Singh, Raghavendra P.; Singh, K. K.; Parihar, Jai Singh

    2017-12-01

    Owing to the lack of consistent spatial time series data on actual evapotranspiration ( ET), very few studies have been conducted on the long-term trend and variability in ET at a national scale over the Indian subcontinent. The present study uses biome specific ET data derived from NOAA satellite's advanced very high resolution radiometer to investigate the trends and variability in ET over India from 1983 to 2006. Trend analysis using the non-parametric Mann-Kendall test showed that the domain average ET decreased during the period at a rate of 0.22 mm year^{-1}. A strong decreasing trend (m = -1.75 mm year^{-1}, F = 17.41, P 0.01) was observed in forest regions. Seasonal analyses indicated a decreasing trend during southwest summer monsoon (m= -0.320 mm season^{-1} year^{-1}) and post-monsoon period (m= -0.188 mm season^{-1 } year^{-1}). In contrast, an increasing trend was observed during northeast winter monsoon (m = 0.156 mm season^{-1 } year^{-1}) and pre-monsoon (m = 0.068 mm season^{-1 } year^{-1}) periods. Despite an overall net decline in the country, a considerable increase ( 4 mm year^{-1}) was observed over arid and semi-arid regions. Grid level correlation with various climatic parameters exhibited a strong positive correlation (r >0.5) of ET with soil moisture and precipitation over semi-arid and arid regions, whereas a negative correlation (r -0.5) occurred with temperature and insolation in dry regions of western India. The results of this analysis are useful for understanding regional ET dynamics and its relationship with various climatic parameters over India. Future studies on the effects of ET changes on the hydrological cycle, carbon cycle, and energy partitioning are needed to account for the feedbacks to the climate.

  19. Global long-term ozone trends derived from different observed and modelled data sets

    Science.gov (United States)

    Coldewey-Egbers, M.; Loyola, D.; Zimmer, W.; van Roozendael, M.; Lerot, C.; Dameris, M.; Garny, H.; Braesicke, P.; Koukouli, M.; Balis, D.

    2012-04-01

    The long-term behaviour of stratospheric ozone amounts during the past three decades is investigated on a global scale using different observed and modelled data sets. Three European satellite sensors GOME/ERS-2, SCIAMACHY/ENVISAT, and GOME-2/METOP are combined and a merged global monthly mean total ozone product has been prepared using an inter-satellite calibration approach. The data set covers the 16-years period from June 1995 to June 2011 and it exhibits an excellent long-term stability, which is required for such trend studies. A multiple linear least-squares regression algorithm using different explanatory variables is applied to the time series and statistically significant positive trends are detected in the northern mid latitudes and subtropics. Global trends are also estimated using a second satellite-based Merged Ozone Data set (MOD) provided by NASA. For few selected geographical regions ozone trends are additionally calculated using well-maintained measurements of individual Dobson/Brewer ground-based instruments. A reasonable agreement in the spatial patterns of the trends is found amongst the European satellite, the NASA satellite, and the ground-based observations. Furthermore, two long-term simulations obtained with the Chemistry-Climate Models E39C-A provided by German Aerospace Center and UMUKCA-UCAM provided by University of Cambridge are analysed.

  20. Assessment of trend and seasonality in road accident data: an Iranian case study.

    Science.gov (United States)

    Razzaghi, Alireza; Bahrampour, Abbas; Baneshi, Mohammad Reza; Zolala, Farzaneh

    2013-06-01

    Road traffic accidents and their related deaths have become a major concern, particularly in developing countries. Iran has adopted a series of policies and interventions to control the high number of accidents occurring over the past few years. In this study we used a time series model to understand the trend of accidents, and ascertain the viability of applying ARIMA models on data from Taybad city. This study is a cross-sectional study. We used data from accidents occurring in Taybad between 2007 and 2011. We obtained the data from the Ministry of Health (MOH) and used the time series method with a time lag of one month. After plotting the trend, non-stationary data in mean and variance were removed using Box-Cox transformation and a differencing method respectively. The ACF and PACF plots were used to control the stationary situation. The traffic accidents in our study had an increasing trend over the five years of study. Based on ACF and PACF plots gained after applying Box-Cox transformation and differencing, data did not fit to a time series model. Therefore, neither ARIMA model nor seasonality were observed. Traffic accidents in Taybad have an upward trend. In addition, we expected either the AR model, MA model or ARIMA model to have a seasonal trend, yet this was not observed in this analysis. Several reasons may have contributed to this situation, such as uncertainty of the quality of data, weather changes, and behavioural factors that are not taken into account by time series analysis.

  1. Assessment of Trend and Seasonality in Road Accident Data: An Iranian Case Study

    Directory of Open Access Journals (Sweden)

    Farzaneh Zolala

    2013-05-01

    Full Text Available Road traffic accidents and their related deaths have become a major concern, particularly in developing countries. Iran has adopted a series of policies and interventions to control the high number of accidents occurring over the past few years. In this study we used a time series model to understand the trend of accidents, and ascertain the viability of applying ARIMA models on data from Taybad city. Methods This study is a cross-sectional study. We used data from accidents occurring in Taybad between 2007 and 2011. We obtained the data from the Ministry of Health (MOH and used the time series method with a time lag of one month. After plotting the trend, non stationary data in mean and variance were removed using Box-Cox transformation and a differencing method respectively. The ACF and PACF plots were used to control the stationary situation. Results The traffic accidents in our study had an increasing trend over the five years of study. Based on ACF and PACF plots gained after applying Box-Cox transformation and differencing, data did not fit to a time series model. Therefore, neither ARIMA model nor seasonality were observed. Conclusion Traffic accidents in Taybad have an upward trend. In addition, we expected either the AR model, MA model or ARIMA model to have a seasonal trend, yet this was not observed in this analysis. Several reasons may have contributed to this situation, such as uncertainty of the quality of data, weather changes, and behavioural factors that are not taken into account by time series analysis.

  2. Study of the spatial resolution for binary readout detectors

    Energy Technology Data Exchange (ETDEWEB)

    Yonamine, R., E-mail: ryo.yonamine@ulb.ac.be; Maerschalk, T.; Lentdecker, G. De

    2016-07-11

    Often the binary readout is proposed for high granularity detectors to reduce the generated data volume to be readout at the price of a somewhat reduced spatial resolution compared to an analogue readout. We have been studying single hit resolutions obtained with a binary readout using simulations as well as analytical approaches. In this note we show that the detector geometry could be optimized to offer an equivalent spatial resolution than with an analogue readout.

  3. Real-time distribution of pelagic fish: combining hydroacoustics, GIS and spatial modelling at a fine spatial scale.

    Science.gov (United States)

    Muška, Milan; Tušer, Michal; Frouzová, Jaroslava; Mrkvička, Tomáš; Ricard, Daniel; Seďa, Jaromír; Morelli, Federico; Kubečka, Jan

    2018-03-29

    Understanding spatial distribution of organisms in heterogeneous environment remains one of the chief issues in ecology. Spatial organization of freshwater fish was investigated predominantly on large-scale, neglecting important local conditions and ecological processes. However, small-scale processes are of an essential importance for individual habitat preferences and hence structuring trophic cascades and species coexistence. In this work, we analysed the real-time spatial distribution of pelagic freshwater fish in the Římov Reservoir (Czechia) observed by hydroacoustics in relation to important environmental predictors during 48 hours at 3-h interval. Effect of diurnal cycle was revealed of highest significance in all spatial models with inverse trends between fish distribution and predictors in day and night in general. Our findings highlighted daytime pelagic fish distribution as highly aggregated, with general fish preferences for central, deep and highly illuminated areas, whereas nighttime distribution was more disperse and fish preferred nearshore steep sloped areas with higher depth. This turnover suggests prominent movements of significant part of fish assemblage between pelagic and nearshore areas on a diel basis. In conclusion, hydroacoustics, GIS and spatial modelling proved as valuable tool for predicting local fish distribution and elucidate its drivers, which has far reaching implications for understanding freshwater ecosystem functioning.

  4. Temporal and spatial distribution of human cryptosporidiosis in the west of Ireland 2004-2007.

    LENUS (Irish Health Repository)

    Callaghan, Mary

    2009-01-01

    BACKGROUND: Cryptosporidiosis is increasingly recognised as a cause of gastrointestinal infection in Ireland and has been implicated in several outbreaks. This study aimed to investigate the spatial and temporal distribution of human cryptosporidiosis in the west of Ireland in order to identify high risk seasons and areas and to compare Classically Calculated (CC) and Empirical Bayesian (EB) incidence rates. Two spatial scales of analysis were used with a view to identifying the best one in assessing geographical patterns of infection. Global Moran\\'s I and Local Moran\\'s I tests of autocorrelation were used to test for evidence of global and local spatial clustering. RESULTS: There were statistically significant seasonal patterns of cryptosporidiosis with peaks in spring and an increasing temporal trend. Significant (p < 0.05) global spatial clustering was observed in CC rates at the Electoral Division (ED) level but not in EB rates at the same level. Despite variations in disease, ED level was found to provide the most accurate account of distribution of cryptosporidiosis in the West of Ireland but required spatial EB smoothing of cases. There were a number of areas identified with significant local clustering of cryptosporidiosis rates. CONCLUSION: This study identified spatial and temporal patterns in cryptosporidiosis distribution. The study also showed benefit in performing spatial analyses at more than one spatial scale to assess geographical patterns in disease distribution and that smoothing of disease rates for mapping in small areas enhances visualisation of spatial patterns. These findings are relevant in guiding policy decisions on disease control strategies.

  5. Generalized index for spatial data sets as a measure of complete spatial randomness

    Science.gov (United States)

    Hackett-Jones, Emily J.; Davies, Kale J.; Binder, Benjamin J.; Landman, Kerry A.

    2012-06-01

    Spatial data sets, generated from a wide range of physical systems can be analyzed by counting the number of objects in a set of bins. Previous work has been limited to equal-sized bins, which are inappropriate for some domains (e.g., circular). We consider a nonequal size bin configuration whereby overlapping or nonoverlapping bins cover the domain. A generalized index, defined in terms of a variance between bin counts, is developed to indicate whether or not a spatial data set, generated from exclusion or nonexclusion processes, is at the complete spatial randomness (CSR) state. Limiting values of the index are determined. Using examples, we investigate trends in the generalized index as a function of density and compare the results with those using equal size bins. The smallest bin size must be much larger than the mean size of the objects. We can determine whether a spatial data set is at the CSR state or not by comparing the values of a generalized index for different bin configurations—the values will be approximately the same if the data is at the CSR state, while the values will differ if the data set is not at the CSR state. In general, the generalized index is lower than the limiting value of the index, since objects do not have access to the entire region due to blocking by other objects. These methods are applied to two applications: (i) spatial data sets generated from a cellular automata model of cell aggregation in the enteric nervous system and (ii) a known plant data distribution.

  6. Analysis of reference evapotranspiration (ET0) trends under climate change in Bangladesh using observed and CMIP5 data sets

    Science.gov (United States)

    Rahman, Mohammad Atiqur; Yunsheng, Lou; Sultana, Nahid; Ongoma, Victor

    2018-03-01

    ET0 is an important hydro-meteorological phenomenon, which is influenced by changing climate like other climatic parameters. This study investigates the present and future trends of ET0 in Bangladesh using 39 years' historical and downscaled CMIP5 daily climatic data for the twenty-first century. Statistical Downscaling Model (SDSM) was used to downscale the climate data required to calculate ET0. Penman-Monteith formula was applied in ET0 calculation for both the historical and modelled data. To analyse ET0 trends and trend changing patterns, modified Mann-Kendall and Sequential Mann-Kendall tests were, respectively, done. Spatial variations of ET0 trends are presented by inverse distance weighting interpolation using ArcGIS 10.2.2. Results show that RCP8.5 (2061-2099) will experience the highest amount of ET0 totals in comparison to the historical and all other scenarios in the same time span of 39 years. Though significant positive trends were observed in the mid and last months of year from month-wise trend analysis of representative concentration pathways, significant negative trends were also found for some months using historical data in similar analysis. From long-term annual trend analysis, it was found that major part of the country represents decreasing trends using historical data, but increasing trends were observed for modelled data. Theil-Sen estimations of ET0 trends in the study depict a good consistency with the Mann-Kendall test results. The findings of the study would contribute in irrigation water management and planning of the country and also in furthering the climate change study using modelled data in the context of Bangladesh.

  7. Bridging Glaciological and Hydrological Trends in the Pamir Mountains, Central Asia

    Directory of Open Access Journals (Sweden)

    Malte Knoche

    2017-06-01

    Full Text Available With respect to meteorological changes and glacier evolution, the southern Pamir Mountains are a transition zone between the Pamirs, Hindu Kush and Karakoram, which are water towers of Central Asia. In this study, we compare runoff and climate trends in multiple time periods with glacial changes reported in the literature. Recent glacier evolution in the Southern Pamirs and its contribution to river runoff are studied in detail. Uncertainties of estimating glacier retreat contribution to runoff are addressed. Runoff trends in the Pamir-Hindu Kush-Karakoram region appear to be a strong proxy for glacier evolution because they exhibit the same spatial pattern as glacial change. There is an anomaly in the North-West Pamirs and Northern Karakoram, showing decreasing runoff trends. In the opposite way, there is a glacier and hydrological change experienced in the Southern Pamirs and Hindu Kush. The prevailing hypothesis for the Karakoram Anomaly, decreasing summer temperatures along with increasing precipitation rates, seems to be valid for the North-Western Pamirs, as well. In the Southern Pamirs, temperature trends have been rising since 1950. Here, the unique water cycle of exclusively winter precipitation does not protect glaciers from accelerated retreat. Snow cover is preset to melt within the seasonal water cycle, due to much lower precipitation amounts falling on glaciers. Therefore, a probable increase in westerly precipitation in both regions causes glacier mass gain in the Northern Pamirs and rising river flows in the Southern Pamirs.

  8. Contrasting runoff trends between dry and wet parts of eastern Tibetan Plateau.

    Science.gov (United States)

    Wang, Yuanyuan; Zhang, Yongqiang; Chiew, Francis H S; McVicar, Tim R; Zhang, Lu; Li, Hongxia; Qin, Guanghua

    2017-11-13

    As the "Asian Water Tower", the Tibetan Plateau (TP) provides water resources for more than 1.4 billion people, but suffers from climatic and environmental changes, followed by the changes in water balance components. We used state-of-the-art satellite-based products to estimate spatial and temporal variations and trends in annual precipitation, evapotranspiration and total water storage change across eastern TP, which were then used to reconstruct an annual runoff variability series for 2003-2014. The basin-scale reconstructed streamflow variability matched well with gauge observations for five large rivers. Annual runoff increased strongly in dry part because of increases in precipitation, but decreased in wet part because of decreases in precipitation, aggravated by noticeable increases in evapotranspiration in the north of wet part. Although precipitation primarily governed temporal-spatial pattern of runoff, total water storage change contributed greatly to runoff variation in regions with wide-spread permanent snow/ice or permafrost. Our study indicates that the contrasting runoff trends between the dry and wet parts of eastern TP requires a change in water security strategy, and attention should be paid to the negative water resources impacts detected for southwestern part which has undergone vast glacier retreat and decreasing precipitation.

  9. Seasonal and spatial distribution of metals in surface sediment of an urban estuary

    International Nuclear Information System (INIS)

    Buggy, Conor J.; Tobin, John M.

    2008-01-01

    Aquatic pollution by metals is of concern because of various toxic effects to marine life. The Tolka Estuary, Co. Dublin, Ireland, is a typical Irish urban estuary. It has a significant metal loading originating from the urban environment. Results of a 25 month analysis of cadmium, copper, lead and zinc spatial and temporal distribution over 10 sample locations in this estuary are presented in this paper. Metal concentrations were analysed using differential pulse polarography. Significant seasonal and spatial trends in metal distribution were observed over the 25 months. Sediment metal concentrations gradually increased (30-120%) in spring to a maximum at the end of summer which was followed by a decrease in winter months (30-60%). Sediment organic matter (OM) concentrations exhibited similar seasonal trends and a positive correlation between OM and metal distributions was observed, implying OM had an influence on metal distributions over time. - Assessment and correlation of the seasonal and spatial distribution of metals and organic matter in surface sediment of an urban estuary

  10. Multifractal spatial patterns and diversity in an ecological succession.

    Directory of Open Access Journals (Sweden)

    Leonardo Ariel Saravia

    Full Text Available We analyzed the relationship between biodiversity and spatial biomass heterogeneity along an ecological succession developed in the laboratory. Periphyton (attached microalgae biomass spatial patterns at several successional stages were obtained using digital image analysis and at the same time we estimated the species composition and abundance. We show that the spatial pattern was self-similar and as the community developed in an homogeneous environment the pattern is self-organized. To characterize it we estimated the multifractal spectrum of generalized dimensions D(q. Using D(q we analyze the existence of cycles of heterogeneity during succession and the use of the information dimension D(1 as an index of successional stage. We did not find cycles but the values of D(1 showed an increasing trend as the succession developed and the biomass was higher. D(1 was also negatively correlated with Shannon's diversity. Several studies have found this relationship in different ecosystems but here we prove that the community self-organizes and generates its own spatial heterogeneity influencing diversity. If this is confirmed with more experimental and theoretical evidence D(1 could be used as an index, easily calculated from remote sensing data, to detect high or low diversity areas.

  11. Exploring spatial evolution of economic clusters: A case study of Beijing

    Science.gov (United States)

    Yang, Zhenshan; Sliuzas, Richard; Cai, Jianming; Ottens, Henk F. L.

    2012-10-01

    An identification of economic clusters and analysing their changing spatial patterns is important for understanding urban economic space dynamics. Previous studies, however, suffer from limitations as a consequence of using fixed geographically areas and not combining functional and spatial dynamics. The paper presents an approach, based on local spatial statistics and the case of Beijing to understand the spatial clustering of industries that are functionally interconnected by common or complementary patterns of demand or supply relations. Using register data of business establishments, it identifies economic clusters and analyses their pattern based on postcodes at different time slices during the period 1983-2002. The study shows how the advanced services occupy the urban centre and key sub centres. The Information and Communication Technology (ICT) cluster is mainly concentrated in the north part of the city and circles the urban centre, and the main manufacturing clusters are evolved in the key sub centers. This type of outcomes improves understanding of urban-economic dynamics, which can support spatial and economic planning.

  12. 1987 wet deposition temporal and spatial patterns in North America

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.C.; Olsen, A.R.

    1990-03-01

    The focus of this report is on North American wet deposition temporal patterns from 1979 to 1987 and spatial patterns for 1987. The report investigates the patterns of annual precipitation-weighted average concentration and annual deposition for nine ion species: hydrogen, sulfate, nitrate, ammonium, calcium, chloride, sodium, potassium, and magnesium. Data are from the Acid Deposition System (ADS) for the statistical reporting of North American deposition data which includes the National Atmospheric Deposition Program/National Trends Network (NADP/NTN), the MAP3S precipitation chemistry network, the Utility Acid Precipitation Study Program (UAPSP), the Canadian Precipitation Monitoring Network (CAPMoN), and the daily and 4-weekly Acidic Precipitation in Ontario Study (APIOS-D and APIOS-C). Mosaic maps, based on surface estimation using kriging, display concentration and deposition spatial patterns of pH, hydrogen, sulfate, nitrate, ammonium, and calcium ion species for 1987 annual, winter, and summer periods. The temporal pattern analyses use a subset of 39 sites over a 9-year (1979--1987) period and an expanded subset of 140 sites with greater spatial coverage over a 6-year (1982--1987) period. 68 refs., 15 figs., 15 tabs.

  13. Estimation of Spatial Trends in LAI in Heterogeneous Semi-arid Ecosystems using Full Waveform Lidar

    Science.gov (United States)

    Glenn, N. F.; Ilangakoon, N.; Spaete, L.; Dashti, H.

    2017-12-01

    Leaf area index (LAI) is a key structural trait that is defined by the plant functional type (PFT) and controlled by prevailing climate- and human-driven ecosystem stresses. Estimates of LAI using remote sensing techniques are limited by the uncertainties of vegetation inter and intra-gap fraction estimates; this is especially the case in sparse, low stature vegetated ecosystems. Small footprint full waveform lidar digitizes the total amount of return energy with the direction information as a near continuous waveform at a high vertical resolution (1 ns). Thus waveform lidar provides additional data matrices to capture vegetation gaps as well as PFTs that can be used to constrain the uncertainties of LAI estimates. In this study, we calculated a radiometrically calibrated full waveform parameter called backscatter cross section, along with other data matrices from the waveform to estimate vegetation gaps across plots (10 m x 10 m) in a semi-arid ecosystem in the western US. The LAI was then estimated using empirical relationships with directional gap fraction. Full waveform-derived gap fraction based LAI showed a high correlation with field observed shrub LAI (R2 = 0.66, RMSE = 0.24) compared to discrete return lidar based LAI (R2 = 0.01, RMSE = 0.5). The data matrices derived from full waveform lidar classified a number of deciduous and evergreen tree species, shrub species, and bare ground with an overall accuracy of 89% at 10 m. A similar analysis was performed at 1m with overall accuracy of 80%. The next step is to use these relationships to map the PFTs LAI at 10 m spatial scale across the larger study regions. The results show the exciting potential of full waveform lidar to identify plant functional types and LAI in low-stature vegetation dominated semi-arid ecosystems, an ecosystem in which many other remote sensing techniques fail. These results can be used to assess ecosystem state, habitat suitability as well as to constrain model uncertainties in

  14. THE STUDY OF SOCIALIZATION TRENDS WITH THE HELP OF THE DIACHRONIC APPROACH

    Directory of Open Access Journals (Sweden)

    Альфия Равилевна Вагапова

    2013-12-01

    Full Text Available  The article studies various socialization trends in the Russian society and the use of the diachronic approach in the study of socialization. It presents a description and the idea of the main socialization trends and studies the reason why they appeared. A number of methodologies and techniques was used to detect the most popular trends and values in teenage, youth and young adult social environment, which are: 1 - social success and self-presentation (the study of the teenagers’ ideas of social success (n=40 has shown that like adults teenagers search the information space for successful models of self-presentation, which could lead to good social standing in the future; 2 - professional success (the study of the views of psychology students on their future career (n=51 showed the demand for successful young professionals existing in the society and possible solutions to the controversial problems and difficulties of present-day Russian society; 3 - the choice of the sphere of self-fulfillment (the author presents comparative data on family values among the sampling of students and young workers (n=56, studies the trends of self-fulfillment among the youth in various aspects of life and discovers that family is only viewed as one of the numerous opportunities and is less important than successful career. The author concludes that socialization is inseparable from the person’s social activity, personal identity and self-fulfillment in the society. The results of the study can be of practical use for psychological consultants and for devising socialization programmes. DOI: http://dx.doi.org/10.12731/2218-7405-2013-9-60

  15. Identification of trend in long term precipitation and reference evapotranspiration over Narmada river basin (India)

    Science.gov (United States)

    Pandey, Brij Kishor; Khare, Deepak

    2018-02-01

    Precipitation and reference evapotranspiration are key parameters in hydro-meteorological studies and used for agricultural planning, irrigation system design and management. Precipitation and evaporative demand are expected to be alter under climate change and affect the sustainable development. In this article, spatial variability and temporal trend of precipitation and reference evapotranspiration (ETo) were investigated over Narmada river basin (India), a humid tropical climatic region. In the present study, 12 and 28 observatory stations were selected for precipitation and ETo, respectively of 102-years period (1901-2002). A rigorous analysis for trend detection was carried out using non parametric tests such as Mann-Kendall (MK) and Spearman Rho (SR). Sen's slope estimator was used to analyze the rate of change in long term series. Moreover, all the stations of basin exhibit positive trend for annual ETo, while 8% stations indicate significant negative trend for mean annual precipitation, respectively. Change points of annual precipitation were identified around the year 1962 applying Buishand's and Pettit's test. Annual mean precipitation reduced by 9% in upper part while increased maximum by 5% in lower part of the basin due temporal changes. Although annual mean ETo increase by 4-12% in most of the region. Moreover, results of the study are very helpful in planning and development of agricultural water resources.

  16. a Study on Variations of Shoreline Changes and Temporal-Spatial Potentiality for Cloud Seeding at Urumia Lake

    Science.gov (United States)

    Agha Taher, R.; Jafari, M.; Fallah, M.; Alavi, A.

    2015-12-01

    time period has been used. In order to reach better results, images from MODIS satellite has been used as auxiliary data for the images that are with an error margin. Initial classification on the images was conducted to distinguish water and non water applications. Neural network classification was applied with specific scales on the images and the two major applications were thereby extracted. Then, in order to authenticate the proceedings, Error matrix and Kappa coefficient has been applied on the classified images. Base pixel method of neural network was used for the purpose of information extraction while authenticity of that was evaluated too. The outcomes display the trend of Urmia shoreline has been approximately constant between the years of 1976 to 1995 and has experienced very low variations. In 1998 the lake experienced increase of water and therefore advancement of the shoreline of the lake due to increase of precipitation and the volume of inflowing water to the basin. During 2000 to 20125, however, the lake's shoreline has experienced a downward trend, which was intensified in 2007 and reached to its most critical level ever since, that is decreasing to about one third. Further, temporal and spatial potentiality evaluation of clouds seeding in Urmia lake zone has been studied as a solution for improvement and recovery of the current status of the lake, and an algorithm was proposed for optimized temporal- spatial study on could seeding. Ecological, meteorological and synoptic data were used for timing study of the cloud's seeding plan, which upon study; it is easy to evaluate precipitation potential and quality of the system. At the next step, the rate of humidity and also stability of the precipitating system can be analyzed using radar acquired data. Whereas extracted date from MODIS images are expressing the spatial position, therefore in order to study the location of the cloud's seeding, MODIS images of the selected time intervals along with

  17. A STUDY ON VARIATIONS OF SHORELINE CHANGES AND TEMPORAL-SPATIAL POTENTIALITY FOR CLOUD SEEDING AT URUMIA LAKE

    Directory of Open Access Journals (Sweden)

    R. Agha Taher

    2015-12-01

    + sensors in the 35 time period has been used. In order to reach better results, images from MODIS satellite has been used as auxiliary data for the images that are with an error margin. Initial classification on the images was conducted to distinguish water and non water applications. Neural network classification was applied with specific scales on the images and the two major applications were thereby extracted. Then, in order to authenticate the proceedings, Error matrix and Kappa coefficient has been applied on the classified images. Base pixel method of neural network was used for the purpose of information extraction while authenticity of that was evaluated too. The outcomes display the trend of Urmia shoreline has been approximately constant between the years of 1976 to 1995 and has experienced very low variations. In 1998 the lake experienced increase of water and therefore advancement of the shoreline of the lake due to increase of precipitation and the volume of inflowing water to the basin. During 2000 to 20125, however, the lake’s shoreline has experienced a downward trend, which was intensified in 2007 and reached to its most critical level ever since, that is decreasing to about one third. Further, temporal and spatial potentiality evaluation of clouds seeding in Urmia lake zone has been studied as a solution for improvement and recovery of the current status of the lake, and an algorithm was proposed for optimized temporal- spatial study on could seeding. Ecological, meteorological and synoptic data were used for timing study of the cloud’s seeding plan, which upon study; it is easy to evaluate precipitation potential and quality of the system. At the next step, the rate of humidity and also stability of the precipitating system can be analyzed using radar acquired data. Whereas extracted date from MODIS images are expressing the spatial position, therefore in order to study the location of the cloud’s seeding, MODIS images of the selected time

  18. Causes of spring vegetation greenness trends in the northern mid-high latitudes from 1982 to 2004

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Jiafu [ORNL; Shi, Xiaoying [ORNL; Thornton, Peter E [ORNL; Shilong, Dr. Piao [Peking University; Xuhui, Dr. Wang [Peking University

    2012-01-01

    The Community Land Model version 4 (CLM4) is applied to explore the spatial temporal patterns of spring (April May) vegetation growth trends over the northern mid high latitudes (NMH) (>25 N) between 1982 and 2004. During the spring season through the 23 yr period, both the satellite-derived and simulated normalized difference vegetation index (NDVI) anomalies show a statistically significant correlation and an overall greening trend within the study area. Consistently with the observed NDVI temperature relation, the CLM4 NDVI shows a significant positive association with the spring temperature anomaly for the NMH, North America and Eurasia. Large study areas experience temperature discontinuity associated with contrasting NDVI trends. Before and after the turning point (TP) of the temperature trends, climatic variability plays a dominant role, while the other environmental factors exert minor effects on the NDVI tendencies. Simulated vegetation growth is broadly stimulated by the increasing atmospheric CO2. Trends show that nitrogen deposition increases NDVI mostly in southeastern China, and decreases NDVI mainly in western Russia after the temperature TP. Furthermore, land use-induced NDVI trends vary roughly with the respective changes in land management practices (crop areas and forest coverage). Our results highlight how non-climatic factors mitigate or exacerbate the impact of temperature on spring vegetation growth, particularly across regions with intensive human activity.

  19. Oklahoma Study of Educator Supply and Demand: Trends and Projections

    Science.gov (United States)

    Berg-Jacobson, Alex; Levin, Jesse

    2015-01-01

    In June 2014, the Oklahoma State Regents of Higher Education (OSRHE) commissioned American Institutes for Research (AIR) to conduct a study to better understand both historical and future predicted trends of educator supply and demand across Oklahoma. OSRHE commissioned the study in partnership with the Oklahoma Commission for Teacher Preparation…

  20. Epidemiological Trends of Spine Trauma: An Australian Level 1 Trauma Centre Study

    Science.gov (United States)

    Tee, J. W.; Chan, C. H. P.; Fitzgerald, M. C. B.; Liew, S. M.; Rosenfeld, J. V.

    2013-01-01

    Knowledge of current epidemiology and spine trauma trends assists in public resource allocation, fine-tuning of primary prevention methods, and benchmarking purposes. Data on all patients with traumatic spine injuries admitted to the Alfred Hospital, Melbourne between May 1, 2009, and January 1, 2011, were collected from the Alfred Trauma Registry, Alfred Health medical database, and Victorian Orthopaedic Trauma Outcomes Registry. Epidemiological trends were analyzed as a general cohort, with comparison cohorts of nonsurvivors versus survivors and elderly versus nonelderly. Linear regression analysis was utilized to demonstrate trends with statistical significance. There were 965 patients with traumatic spine injuries with 2,333 spine trauma levels. The general cohort showed a trimodal age distribution, male-to-female ratio of 2:2, motor vehicle accidents as the primary spine trauma mechanism, 47.7% patients with severe polytrauma as graded using the Injury Severity Score (ISS), 17.3% with traumatic brain injury (TBI), the majority of patients with one spine injury level, 7% neurological deficit rate, 12.8% spine trauma operative rate, and 5.2% mortality rate. Variables with statistical significance trending toward mortality were the elderly, motor vehicle occupants, severe ISS, TBI, C1–2 dissociations, and American Spinal Injury Association (ASIA) A, B, and C neurological grades. Variables with statistical significance trending toward the elderly were females; low falls; one spine injury level; type 2 odontoid fractures; subaxial cervical spine distraction injuries; ASIA A, B, and C neurological grades; and patients without neurological deficits. Of the general cohort, 50.3% of spine trauma survivors were discharged home, and 48.1% were discharged to rehabilitation facilities. This study provides baseline spine trauma epidemiological data. The trimodal age distribution of patients with traumatic spine injuries calls for further studies and intervention targeted

  1. Exploring the effects of spatial autocorrelation when identifying key drivers of wildlife crop-raiding.

    Science.gov (United States)

    Songhurst, Anna; Coulson, Tim

    2014-03-01

    Few universal trends in spatial patterns of wildlife crop-raiding have been found. Variations in wildlife ecology and movements, and human spatial use have been identified as causes of this apparent unpredictability. However, varying spatial patterns of spatial autocorrelation (SA) in human-wildlife conflict (HWC) data could also contribute. We explicitly explore the effects of SA on wildlife crop-raiding data in order to facilitate the design of future HWC studies. We conducted a comparative survey of raided and nonraided fields to determine key drivers of crop-raiding. Data were subsampled at different spatial scales to select independent raiding data points. The model derived from all data was fitted to subsample data sets. Model parameters from these models were compared to determine the effect of SA. Most methods used to account for SA in data attempt to correct for the change in P-values; yet, by subsampling data at broader spatial scales, we identified changes in regression estimates. We consequently advocate reporting both model parameters across a range of spatial scales to help biological interpretation. Patterns of SA vary spatially in our crop-raiding data. Spatial distribution of fields should therefore be considered when choosing the spatial scale for analyses of HWC studies. Robust key drivers of elephant crop-raiding included raiding history of a field and distance of field to a main elephant pathway. Understanding spatial patterns and determining reliable socio-ecological drivers of wildlife crop-raiding is paramount for designing mitigation and land-use planning strategies to reduce HWC. Spatial patterns of HWC are complex, determined by multiple factors acting at more than one scale; therefore, studies need to be designed with an understanding of the effects of SA. Our methods are accessible to a variety of practitioners to assess the effects of SA, thereby improving the reliability of conservation management actions.

  2. Modeling trends of health and health related indicators in Ethiopia (1995-2008: a time-series study

    Directory of Open Access Journals (Sweden)

    Nigatu Tilahun H

    2009-12-01

    Full Text Available Abstract Background The Federal Ministry of Health of Ethiopia has been publishing Health and Health related indicators of the country annually since 1987 E.C. These indicators have been of high importance in indicating the status of health in the country in those years. However, the trends/patterns of these indicators and the factors related to the trends have not yet been investigated in a systematic manner. In addition, there were minimal efforts to develop a model for predicting future values of Health and Health related indicators based on the current trend. Objectives The overall aim of this study was to analyze trends of and develop model for prediction of Health and Health related indicators. More specifically, it described the trends of Health and Health related indicators, identified determinants of mortality and morbidity indicators and developed model for predicting future values of MDG indicators. Methods This study was conducted on Health and Health related indicators of Ethiopia from the year 1987 E.C to 2000 E.C. Key indicators of Mortality and Morbidity, Health service coverage, Health systems resources, Demographic and socio-economic, and Risk factor indicators were extracted and analyzed. The trends in these indicators were established using trend analysis techniques. The determinants of the established trends were identified using ARIMA models in STATA. The trend-line equations were then used to predict future values of the indicators. Results Among the mortality indicators considered in this study, it was only Maternal Mortality Ratio that showed statistically significant decrement within the study period. The trends of Total Fertility Rate, physician per 100,000 population, skilled birth attendance and postnatal care coverage were found to have significant association with Maternal Mortality Ratio trend. There was a reversal of malaria parasite prevalence in 1999 E.C from Plasmodium Falciparum to Plasmodium Vivax. Based on

  3. The Spatial Variability of Beryllium-7 Depth Distribution Study

    International Nuclear Information System (INIS)

    Jalal Sharib; Zainudin Othman; Dainee Nor Fardzila Ahmad Tugi; Noor Fadzilah Yusof; Mohd Tarmizi Ishak

    2015-01-01

    The objective of this paper is to study the spatial variability of 7 Be depth evolution in soil profile at two different sampling sites. The soil samples have been collected by using metal core in bare area in Bangi, Selangor and Timah Tasoh, Perlis , Malaysia. Two composite core samples for each sampling sites has been sectioned into 2 mm increments to a depth of 4 cm and oven dried at 45- 60 degree Celsius and gently desegregated. These two composite spatial samples are passed through a < 2 mm sieve and packed into proper geometry plastic container for 7 Be analysis by using gamma spectrometry with a 24-hour count time. From the findings, the 7 Be content in the soil samples from Bangi, Selangor study area is distributed lower depth penetration into the soil profile than Timah Tasoh, Perlis catchment due to many factors such as precipitation (fallout) and others. However, the spatial variability from both samples study area is also decreases exponentially with depth and is confined within the top few centimeters and similar with other works been reported (Blake et al., (2000) and Walling et al.,(2008). Furthermore, a detailed discussion from this study findings will be in full papers. (author)

  4. Temporal and Spatial Melanoma Trends in Austria: An Ecological Study

    Directory of Open Access Journals (Sweden)

    Daniela Haluza

    2014-01-01

    Full Text Available Annual solar ultraviolet radiation (UVR is mostly determined by latitude and altitude. Over the last decades, increasing UVR ground levels have been observed. Exposure to UVR is associated with a life-time risk to develop melanoma, a malign skin cancer. Thus, we hypothesized that melanoma incidence in Austria is associated with altitude of place of living and time of diagnosis. We investigated this hypothesis in an ecological study by district and year for Austrian melanoma incidence (1990–2010 and mortality (1970–2011 data. As expected, incidence rates increased with altitude (about 2% per 10 m and year (about 2%. Additionally, melanoma incidence rates were about 50% higher in urban than in rural districts. In contrast, mortality rates decreased with altitude (for males: 0.4% per 10 m, for women: 0.7% per 10 m, respectively. The observed discrepancy between incidence and mortality data could partly be explained by melanoma diagnosis at earlier tumor stage in districts with higher altitude. Possible reasons for this finding include higher awareness of patients, better diagnostic performance of medical professionals working at higher altitudes, or slower tumor growth due to protective effects of sun light-associated vitamin D synthesis.

  5. Temporal and Spatial Melanoma Trends in Austria: An Ecological Study

    Science.gov (United States)

    Haluza, Daniela; Simic, Stana; Moshammer, Hanns

    2014-01-01

    Annual solar ultraviolet radiation (UVR) is mostly determined by latitude and altitude. Over the last decades, increasing UVR ground levels have been observed. Exposure to UVR is associated with a life-time risk to develop melanoma, a malign skin cancer. Thus, we hypothesized that melanoma incidence in Austria is associated with altitude of place of living and time of diagnosis. We investigated this hypothesis in an ecological study by district and year for Austrian melanoma incidence (1990–2010) and mortality (1970–2011) data. As expected, incidence rates increased with altitude (about 2% per 10 m) and year (about 2%). Additionally, melanoma incidence rates were about 50% higher in urban than in rural districts. In contrast, mortality rates decreased with altitude (for males: 0.4% per 10 m, for women: 0.7% per 10 m, respectively). The observed discrepancy between incidence and mortality data could partly be explained by melanoma diagnosis at earlier tumor stage in districts with higher altitude. Possible reasons for this finding include higher awareness of patients, better diagnostic performance of medical professionals working at higher altitudes, or slower tumor growth due to protective effects of sun light-associated vitamin D synthesis. PMID:24398911

  6. Different trends in extreme and median surface aerosol extinction coefficients over China inferred from quality-controlled visibility data

    Science.gov (United States)

    Li, Jing; Li, Chengcai; Zhao, Chunsheng

    2018-03-01

    Although the temporal changes in aerosol properties have been widely investigated, the majority of studies has focused on average conditions without much emphasis on the extremes. However, the latter can be more important in terms of human health and climate change. This study uses a previously validated, quality-controlled visibility dataset to investigate the long-term trends (expressed in terms of relative changes) in extreme surface aerosol extinction coefficient (AEC) over China and compares them with the median trends. Two methods are used to independently evaluate the trends, which arrive at consistent results. The signs of extreme and median trends are generally coherent, whereas their magnitudes show distinct spatial and temporal differences. In the 1980s, an overall positive trend is found throughout China with the extreme trend exceeding the mean trend, except for northwest China and the North China Plain. In the 1990s, AEC over northeast and northwest China started to decline while the rest of the country still exhibited an increase. The extreme trends continued to dominate in the south while they yielded to the mean trend in the north. After the year 2000, the extreme trend became weaker than the mean trend overall in terms of both the magnitude and significance level. The annual trend can be primarily attributed to winter and fall trends. The results suggest that the decadal changes in pollution in China may be governed by different mechanisms. Synoptic conditions that often result in extreme air quality changes might have dominated in the 1980s, whereas emission increase might have been the main factor for the 2000s.

  7. Estimates and 25-year trends of the global burden of disease attributable to ambient air pollution : an analysis of data from the Global Burden of Diseases Study 2015

    NARCIS (Netherlands)

    Cohen, Aaron J; Brauer, Michael; Burnett, Richard; Anderson, H Ross; Frostad, Joseph; Estep, Kara; Balakrishnan, Kalpana; Brunekreef, Bert|info:eu-repo/dai/nl/067548180; Dandona, Lalit; Dandona, Rakhi; Feigin, Valery; Freedman, Greg; Hubbell, Bryan; Jobling, Amelia; Kan, Haidong; Knibbs, Luke; Liu, Yang|info:eu-repo/dai/nl/411298119; Martin, Randall; Morawska, Lidia; Pope, C Arden; Shin, Hwashin; Straif, Kurt; Shaddick, Gavin; Thomas, Matthew; van Dingenen, Rita; van Donkelaar, Aaron; Vos, Theo; Murray, Christopher J L; Forouzanfar, Mohammad H

    BACKGROUND: Exposure to ambient air pollution increases morbidity and mortality, and is a leading contributor to global disease burden. We explored spatial and temporal trends in mortality and burden of disease attributable to ambient air pollution from 1990 to 2015 at global, regional, and country

  8. A representation of place attachment: A study of spatial cognition in Latvia

    Science.gov (United States)

    Skilters, Jurgis; Zarina, Liga; Raita, Liva

    2017-04-01

    Perception of geographical space is reflected in place attachment, i.e., a multidimensional cognitive-affective link between humans and their spatial environment. Place attachment balances emotions, conception of proximity. It is both social and spatial cognitive structure. Place attachment has an impact on people's actions, which in turn reversibly affect the environment in which people live. Place attachment provides emotional regulation for humans linking local - neighborhood-scale and country and world-scale environments. In Latvia a large-scale spatial cognition study has been conducted within participatory research project „Telpas pavasaris" ("Spatial Spring") by foundation Viegli. In the study 1523 respondents reported their associations characterizing certain type of places (e.g., safe place, dangerous place, far place, close place, dear place). The answers were analyzed according to several cognitive-affective categories including modes of experience, emotional valence, geographical distance, and perceptual modality. The current results indicate that socio-cognitive and affective information are primary in respect to purely spatial information (referring to spatial objects or regions and their relations). However, different types of geographical places and spatial objects (natural or artefactual) have to be distinguished and are significant to a different degree. Our results are important for environmental and urban planning because they show the ways how socio-cognitive and affective knowledge shapes the spatial cognition of geographic environment.

  9. Application and Analysis of Measurement Model for Calibrating Spatial Shear Surface in Triaxial Test

    Science.gov (United States)

    Zhang, Zhihua; Qiu, Hongsheng; Zhang, Xiedong; Zhang, Hang

    2017-12-01

    Discrete element method has great advantages in simulating the contacts, fractures, large displacement and deformation between particles. In order to analyze the spatial distribution of the shear surface in the three-dimensional triaxial test, a measurement model is inserted in the numerical triaxial model which is generated by weighted average assembling method. Due to the non-visibility of internal shear surface in laboratory, it is largely insufficient to judge the trend of internal shear surface only based on the superficial cracks of sheared sample, therefore, the measurement model is introduced. The trend of the internal shear zone is analyzed according to the variations of porosity, coordination number and volumetric strain in each layer. It shows that as a case study on confining stress of 0.8 MPa, the spatial shear surface is calibrated with the results of the rotated particle distribution and the theoretical value with the specific characteristics of the increase of porosity, the decrease of coordination number, and the increase of volumetric strain, which represents the measurement model used in three-dimensional model is applicable.

  10. Trends in mercury wet deposition and mercury air concentrations across the U.S. and Canada

    Science.gov (United States)

    Weiss-Penzias, Peter S.; Gay, David A.; Brigham, Mark E.; Parsons, Matthew T.; Gustin, Mae S.; ter Shure, Arnout

    2016-01-01

    This study examined the spatial and temporal trends of mercury (Hg) in wet deposition and air concentrations in the United States (U.S.) and Canada between 1997 and 2013. Data were obtained from the National Atmospheric Deposition Program (NADP) and Environment Canada monitoring networks, and other sources. Of the 19 sites with data records from 1997–2013, 53% had significant negative trends in Hg concentration in wet deposition, while no sites had significant positive trends, which is in general agreement with earlier studies that considered NADP data up until about 2010. However, for the time period 2007–2013 (71 sites), 17% and 13% of the sites had significant positive and negative trends, respectively, and for the time period 2008–2013 (81 sites) 30% and 6% of the sites had significant positive and negative trends, respectively. Non-significant positive tendencies were also widespread. Regional trend analyses revealed significant positive trends in Hg concentration in the Rocky Mountains, Plains, and Upper Midwest regions for the recent time periods in addition to significant positive trends in Hg deposition for the continent as a whole. Sulfate concentration trends in wet deposition were negative in all regions, suggesting a lower importance of local Hg sources. The trend in gaseous elemental Hg from short-term datasets merged as one continuous record was broadly consistent with trends in Hg concentration in wet deposition, with the early time period (1998–2007) producing a significantly negative trend (− 1.5 ± 0.2% year− 1) and the recent time period (2008–2013) displaying a flat slope (− 0.3 ± 0.1% year− 1, not significant). The observed shift to more positive or less negative trends in Hg wet deposition primarily seen in the Central-Western regions is consistent with the effects of rising Hg emissions from regions outside the U.S. and Canada and the influence of long-range transport in the free troposphere.

  11. Influence of macular pigment optical density spatial distribution on intraocular scatter.

    Science.gov (United States)

    Putnam, Christopher M; Bland, Pauline J; Bassi, Carl J

    This study evaluated the summed measures of macular pigment optical density (MPOD) spatial distribution and their effects on intraocular scatter using a commercially available device (C-Quant, Oculus, USA). A customized heterochromatic flicker photometer (cHFP) device was used to measure MPOD spatial distribution across the central 16° using a 1° stimulus. MPOD was calculated as a discrete measure and summed measures across the central 1°, 3.3°, 10° and 16° diameters. Intraocular scatter was determined as a mean of 5 trials in which reliability and repeatability measures were met using the C-Quant. MPOD spatial distribution maps were constructed and the effects of both discrete and summed values on intraocular scatter were examined. Spatial mapping identified mean values for discrete MPOD [0.32 (s.d.=0.08)], MPOD summed across central 1° [0.37 (s.d.=0.11)], MPOD summed across central 3.3° [0.85 (s.d.=0.20)], MPOD summed across central 10° [1.60 (s.d.=0.35)] and MPOD summed across central 16° [1.78 (s.d.=0.39)]. Mean intraocular scatter was 0.83 (s.d.=0.16) log units. While there were consistent trends for an inverse relationship between MPOD and scatter, these relationships were not statistically significant. Correlations between the highest and lowest quartiles of MPOD within the central 1° were near significance. While there was an overall trend of decreased intraocular forward scatter with increased MPOD consistent with selective short wavelength visible light attenuation, neither discrete nor summed values of MPOD significantly influence intraocular scatter as measured by the C-Quant device. Published by Elsevier España, S.L.U.

  12. CHANGING TRENDS IN CAESAREAN DELIVERY - A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Annappa Shetty

    2016-10-01

    Full Text Available BACKGROUND Today, there is a concern over the rising caesarean delivery both in the developed and developing countries across the world. It has been observed that both primary and repeat caesarean deliveries have been increasing at an alarming rate. Indications for caesarean deliveries also shows changing trends in the present scenario. The main aim of this study is to compare the caesarean delivery rates over the last one decade. The objective behind the study is to understand the contributing factors for the new trends. MATERIALS AND METHODS For this study, the data was collected in a retrospective manner from all the deliveries that occurred between July 1, 2005, to June 30, 2006, and July 2015 to June 30, 2016, in the Department of Obstetrics and Gynaecology, Karwar Institute of Medical Science, Karwar. A cohort of 2752 delivered women were studied. Among the caesarean births, the indications for both the primary and repeat caesarean sections were studied. After analysing the caesarean births from total live births, the rate for both primary and repeat caesarean were calculated. RESULTS The caesarean delivery rate is increased from 167 to 263 for 1000 live births with increase in primary caesarean delivery rate from 101 (10.1% to 187 (18.7% per 1000 live births in last one decade. Foetal distress, cephalopelvic disproportion, arrest of descent, multiple gestations, breech presentation contributed to this increase. CONCLUSION There is an increase in the total caesarean rate with significant rise in the primary caesarean rate in the last one decade.

  13. Mapping cycling patterns and trends using Strava Metro data in the city of Johannesburg, South Africa.

    Science.gov (United States)

    Musakwa, Walter; Selala, Kadibetso M

    2016-12-01

    Plans for smart mobility through cycling are often hampered by lack of information on cycling patterns and trends, particularly in cities of the developing world such as Johannesburg. Similarly, traditional methods of data collection such as bicycle counts are often expensive, cover a limited spatial extent and not up-to-date. Consequently, the dataset presented in this paper illustrates the spatial and temporal coverage of cycling patterns and trends in Johannesburg for the year 2014 derived from the geolocation based mobile application Strava. To the best knowledge of the authors, there is little or no comprehensive dataset that describes cycling patterns in Johannesburg. Perhaps this dataset is a tool that will support evidence based transportation planning and smart mobility.

  14. Comparison of Three Plot Selection Methods for Estimating Change in Temporally Variable, Spatially Clustered Populations.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William L. [Bonneville Power Administration, Portland, OR (US). Environment, Fish and Wildlife

    2001-07-01

    Monitoring population numbers is important for assessing trends and meeting various legislative mandates. However, sampling across time introduces a temporal aspect to survey design in addition to the spatial one. For instance, a sample that is initially representative may lose this attribute if there is a shift in numbers and/or spatial distribution in the underlying population that is not reflected in later sampled plots. Plot selection methods that account for this temporal variability will produce the best trend estimates. Consequently, I used simulation to compare bias and relative precision of estimates of population change among stratified and unstratified sampling designs based on permanent, temporary, and partial replacement plots under varying levels of spatial clustering, density, and temporal shifting of populations. Permanent plots produced more precise estimates of change than temporary plots across all factors. Further, permanent plots performed better than partial replacement plots except for high density (5 and 10 individuals per plot) and 25% - 50% shifts in the population. Stratified designs always produced less precise estimates of population change for all three plot selection methods, and often produced biased change estimates and greatly inflated variance estimates under sampling with partial replacement. Hence, stratification that remains fixed across time should be avoided when monitoring populations that are likely to exhibit large changes in numbers and/or spatial distribution during the study period. Key words: bias; change estimation; monitoring; permanent plots; relative precision; sampling with partial replacement; temporary plots.

  15. Integrating Spatial and Attribute Characteristics of Extended Voronoi Diagrams in Spatial Patterning Research: A Case Study of Wuhan City in China

    Directory of Open Access Journals (Sweden)

    Zuohua Miao

    2016-07-01

    Full Text Available Rapid urbanization has caused numerous problems, and the urban spatial structure has been a hot topic in sustainable development management. Urban spatial structure is affected by a series of factors. Thus, the research model should synthetically consider the spatial and non-spatial relationship of every element. Here, we propose an extended Voronoi diagram for exploring the urban land spatial pattern. In essence, we first used a principal component analysis method to construct attribute evaluation indicators and obtained the attribute distance for each indicator. Second, we integrated spatial and attribute distances to extend the comparison distance for Voronoi diagrams, and then, we constructed the Voronoi aggregative homogeneous map of the study area. Finally, we make a spatial autocorrelation analysis by using GeoDA and SPSS software. Results show that: (1 the residential land cover aggregation is not significant, but spatial diffusion is obvious; (2 the commercial land cover aggregation is considerable; and (3 the spatial agglomeration degree of the industrial land cover is increased and mainly located in urban fringes. According to the neo-Marxist theory, we briefly analyzed the driving forces for shaping the urban spatial structure. To summarize, our approach yields important insights into the urban spatial structure characterized by attribute similarity with geospatial proximity, which contributes to a better understanding of the urban growth mechanism. In addition, it explicitly identifies ongoing urban transformations, potentially supporting the planning for sustainable urban land use and protection.

  16. World-wide trend of long-lived radionuclides transmutation studies

    International Nuclear Information System (INIS)

    Kim, Young Hwan; Lee, Il Hee; Yoo, Jae Hyung

    1997-01-01

    The objective of this study is to review the concepts of partitioning and transmutation studies which are being conducted in several countries. This review was focused on the analysis of such areas as radiotoxicities of radwaste containing long-lived radionuclides, transmutation by reactors or accelerators, and separation of minor actinides. The world-wide trend of partitioning and transmutation studies was also investigated on the basis of each country's R and D activities in this area. (author). 5 refs., 4 tabs., 3 figs

  17. [Comparison of application of Cochran-Armitage trend test and linear regression analysis for rate trend analysis in epidemiology study].

    Science.gov (United States)

    Wang, D Z; Wang, C; Shen, C F; Zhang, Y; Zhang, H; Song, G D; Xue, X D; Xu, Z L; Zhang, S; Jiang, G H

    2017-05-10

    We described the time trend of acute myocardial infarction (AMI) from 1999 to 2013 in Tianjin incidence rate with Cochran-Armitage trend (CAT) test and linear regression analysis, and the results were compared. Based on actual population, CAT test had much stronger statistical power than linear regression analysis for both overall incidence trend and age specific incidence trend (Cochran-Armitage trend P valuelinear regression P value). The statistical power of CAT test decreased, while the result of linear regression analysis remained the same when population size was reduced by 100 times and AMI incidence rate remained unchanged. The two statistical methods have their advantages and disadvantages. It is necessary to choose statistical method according the fitting degree of data, or comprehensively analyze the results of two methods.

  18. Trend analysis of the aerosol optical depth from fusion of MISR and MODIS retrievals over China

    International Nuclear Information System (INIS)

    Guo, Jing; Gu, Xingfa; Yu, Tao; Cheng, Tianhai; Chen, Hao

    2014-01-01

    Atmospheric aerosol plays an important role in the climate change though direct and indirect processes. In order to evaluate the effects of aerosols on climate, it is necessary to have a research on their spatial and temporal distributions. Satellite aerosol remote sensing is a developing technology that may provide good temporal sampling and superior spatial coverage to study aerosols. The Moderate Resolution Imaging Spectroradiometer (MODIS) and Multi-angle Imaging Spectroradiometer (MISR) have provided aerosol observations since 2000, with large coverage and high accuracy. However, due to the complex surface, cloud contamination, and aerosol models used in the retrieving process, the uncertainties still exist in current satellite aerosol products. There are several observed differences in comparing the MISR and MODIS AOD data with the AERONET AOD. Combing multiple sensors could reduce uncertainties and improve observational accuracy. The validation results reveal that a better agreement between fusion AOD and AERONET AOD. The results confirm that the fusion AOD values are more accurate than single sensor. We have researched the trend analysis of the aerosol properties over China based on nine-year (2002-2010) fusion data. Compared with trend analysis in Jingjintang and Yangtze River Delta, the accuracy has increased by 5% and 3%, respectively. It is obvious that the increasing trend of the AOD occurred in Yangtze River Delta, where human activities may be the main source of the increasing AOD

  19. A two-dimensional model study of past trends in global ozone

    International Nuclear Information System (INIS)

    Wuebbles, D.J.; Kinnison, D.E.

    1988-08-01

    Emissions and atmospheric concentrations of several trace gases important to atmospheric chemistry are known to have increased substantially over recent decades. Solar flux variations and the atmospheric nuclear test series are also likely to have affected stratospheric ozone. In this study, the LLNL two-dimensional chemical-radiative-transport model of the troposphere and stratosphere has been applied to an analysis of the effects that these natural and anthropogenic influences may have had on global ozone concentrations over the last three decades. In general, model determined species distributions and the derived ozone trends agree well with published analyses of land-based and satellite-based observations. Also, the total ozone and ozone distribution trends derived from CFC and other trace gas effects have a different response with latitude than the derived trends from solar flux variations, thus providing a ''signature'' for anthropogenic effects on ozone. 24 refs., 5 figs

  20. Policy Implementation Study on Spatial Planning for Environmental Conflict (Study Location: Rembang Regency)

    Science.gov (United States)

    Kusyuniadi, Indraya

    2018-02-01

    This study aims to see the impact and benefits as an outcome of a policy, where this policy is in the form of spatial planning (Regional Planning). As known RTRW is a product that can be regarded as "the book of development" in every region both in the provincial and regional levels. One of them is as a decision tool for investors (investors) in increasing local development investment, spatial planning (RTRW) is also expected to maintain the environment, in order to support the sustainability of regional development. In reality, there are still many conflicts of interest in the implementation process of regional development, especially between economic and environmental interests. Often the interests of regional sustainability are placed at a lower level (less priority) than investment / economy. Land conversion that is inconsistent with district / city spatial planning RTRW is relatively still occurring, especially for economic purposes. Lack of policy called spatial plan in this case RTRW Province and Regency in responding to existing condition in field. How can a product that is said to be "Scripture" a regional planning is powerless in fulfilling the space for investment in the form of industry, commercial, housing and so forth. There are several results that can be concluded in this study. Basically, the importance of the environment at least can be used as the basis or priority of the main decision makers above economic interests and other politic interests. The current Spatial Plan / RTRW document still holds a big question whether at the time of compilation it follows the norms and rules in a plan (data accuracy, through input process from the community).

  1. Policy Implementation Study on Spatial Planning for Environmental Conflict (Study Location: Rembang Regency

    Directory of Open Access Journals (Sweden)

    Kusyuniadi Indraya

    2018-01-01

    Full Text Available This study aims to see the impact and benefits as an outcome of a policy, where this policy is in the form of spatial planning (Regional Planning. As known RTRW is a product that can be regarded as "the book of development" in every region both in the provincial and regional levels. One of them is as a decision tool for investors (investors in increasing local development investment, spatial planning (RTRW is also expected to maintain the environment, in order to support the sustainability of regional development. In reality, there are still many conflicts of interest in the implementation process of regional development, especially between economic and environmental interests. Often the interests of regional sustainability are placed at a lower level (less priority than investment / economy. Land conversion that is inconsistent with district / city spatial planning RTRW is relatively still occurring, especially for economic purposes. Lack of policy called spatial plan in this case RTRW Province and Regency in responding to existing condition in field. How can a product that is said to be "Scripture" a regional planning is powerless in fulfilling the space for investment in the form of industry, commercial, housing and so forth. There are several results that can be concluded in this study. Basically, the importance of the environment at least can be used as the basis or priority of the main decision makers above economic interests and other politic interests. The current Spatial Plan / RTRW document still holds a big question whether at the time of compilation it follows the norms and rules in a plan (data accuracy, through input process from the community.

  2. A simple spatial working memory and attention test on paired symbols shows developmental deficits in schizophrenia patients.

    Science.gov (United States)

    Song, Wei; Zhang, Kai; Sun, Jinhua; Ma, Lina; Jesse, Forrest Fabian; Teng, Xiaochun; Zhou, Ying; Bao, Hechen; Chen, Shiqing; Wang, Shuai; Yang, Beimeng; Chu, Xixia; Ding, Wenhua; Du, Yasong; Cheng, Zaohuo; Wu, Bin; Chen, Shanguang; He, Guang; He, Lin; Chen, Xiaoping; Li, Weidong

    2013-01-01

    People with neuropsychiatric disorders such as schizophrenia often display deficits in spatial working memory and attention. Evaluating working memory and attention in schizophrenia patients is usually based on traditional tasks and the interviewer's judgment. We developed a simple Spatial Working Memory and Attention Test on Paired Symbols (SWAPS). It takes only several minutes to complete, comprising 101 trials for each subject. In this study, we tested 72 schizophrenia patients and 188 healthy volunteers in China. In a healthy control group with ages ranging from 12 to 60, the efficiency score (accuracy divided by reaction time) reached a peak in the 20-27 age range and then declined with increasing age. Importantly, schizophrenia patients failed to display this developmental trend in the same age range and adults had significant deficits compared to the control group. Our data suggests that this simple Spatial Working Memory and Attention Test on Paired Symbols can be a useful tool for studies of spatial working memory and attention in neuropsychiatric disorders.

  3. Spatial Econometric Research on the Relationship between Highway Construction and Regional Economic Growth in China: Evidence from the Nationwide Panel Data

    Science.gov (United States)

    Ye, N. J.; Li, W. J.; Li, Y.; Bai, Y. F.

    2017-12-01

    Based on spatial panel data from 2010 to 2016 in China, this paper makes an empirical analysis on the relationship between highway construction and regional economic growth by means of spatial econometric model. The results show that there is positive spatial correlation on regional economic growth in China, and strong spatial dependences between some provinces and cities appear, specifically, Hebei, Beijing, Tianjin, Shanghai, Zhejiang and other eastern coastal areas show high-high agglomeration trend, the Pearl River Delta region presents high-low agglomeration trend; In terms of nationwide provinces and municipalities, a province’s highway construction investment for their own province and the neighboring provinces has pulling effect on economic growth to a certain extent, and the direct effect is more obvious.

  4. Spatial and Decadal Variations in Potential Evapotranspiration of China Based on Reanalysis Datasets during 1982–2010

    Directory of Open Access Journals (Sweden)

    Yunjun Yao

    2014-10-01

    Full Text Available Potential evapotranspiration (PET is an important indicator of atmospheric evaporation demand and has been widely used to characterize hydrological change. However, sparse observations of pan evaporation (EP prohibit the accurate characterization of the spatial and temporal patterns of PET over large spatial scales. In this study, we have estimated PET of China using the Penman-Monteith (PM method driven by gridded reanalysis datasets to analyze the spatial and decadal variations of PET in China during 1982–2010. The results show that the estimated PET has decreased on average by 3.3 mm per year (p < 0.05 over China during 1982–1993, while PET began to increase since 1994 by 3.4 mm per year (p < 0.05. The spatial pattern of the linear trend in PET of China illustrates that a widely significant increasing trend in PET appears during 1982–2010 in Northwest China, Central China, Northeast China and South China while there are no obvious variations of PET in other regions. Our findings illustrate that incident solar radiation (Rs is the largest contributor to the variation of PET in China, followed by vapor pressure deficit (VPD, air temperature (Tair and wind speed (WS. However, WS is the primary factor controlling inter-annual variation of PET over Northwest China.

  5. Spatial analysis for prevalence of type 2 diabetes mellitus - A state investigation

    Science.gov (United States)

    Zainal, Siti Salsabilah Nabilah; Masnan, Maz Jamilah; Amin, Nor Azrita Mohd; Mohamed, Nordin

    2017-11-01

    Type 2 Diabetes Mellitus (T2DM) is a chronic and non-communicable disease, which is characterized as the cause of premature deaths in the world. Unfortunately, Malaysia is one of the many countries facing this epidemic. Based on the increasing current trend of T2DM patients' cases from the National Diabetes Registry (NDR) Report from 2009 to 2012, there were approximately 2.6 million adults aged 18 years and above living with diabetes disease in Malaysia. Thus, this study aims to (i) perform preliminary spatial analysis for the prevalence of T2DM patients based on some factors, (ii) map the findings of the analyses according to some spatial properties, and (iii) analyze the pattern of diagnosed T2DM patients based on the studied factors. The studied population is one of the highest prevalence states of T2DM in Malaysia. This study is expected to reveal some demographic patterns that probably significant to this alarming epidemic.

  6. Time-Spatial Convergence of Air Pollution and Regional Economic Growth in China

    Directory of Open Access Journals (Sweden)

    Zhengning Pu

    2017-07-01

    Full Text Available The haze pollution caused by fine particulate matter (PM 2.5 emissions has become one of the most crucial topics of sustainable environmental governance in China. Using the average concentration of PM 2.5 in China’s key cities from 2000 to 2012, as measured by aerosol optical depth, this study tested the time-spatial convergence of fine particulate matter pollution in China. The results show that there is a trend of absolute convergence between timespan and China’s PM 2.5 emissions. At the same time, in the geographic areas divided by the east, middle and west zones, there is a significant difference in the convergence rate of PM 2.5. The growth rate of PM 2.5 in the middle and west zones is significantly higher than that of the east zone. The correlation test between regional economic growth and PM 2.5 emissions suggest a significant positive N-type Environmental Kuznets Curve (EKC after considering spatial lag and spatial error effect.

  7. Temporal and spatial variations in the magnitude of completeness ...

    Indian Academy of Sciences (India)

    mogenic zones keeping in view the spatial variations in earthquake occurrence and prevalent tectonics. Mc, 'b' and 'a' values have been estimated with respect to each zone, and the ..... ing largely EW trends and deeper events depict relatively higher 'b' values of 0.88 and 0.78, respec- tively. Seismogenic zones, VII and ...

  8. Infrastructure Mega projects and Spatial Polarization in Rio de Janeiro

    DEFF Research Database (Denmark)

    Silva, Victor; Ribeiro, Gustavo

    2008-01-01

    This paper looks at a prominent example of planning for sustainable development in Rio de Janeiro, namely the Guanabara Bay Clean-up Programme. We examine the role of the Guanabara Bay Clean-up Programme against the background of socio-economic and spatial trends in the last decade, identifying......-way containing the main traffic towards Rio de Janeiro International Airport. The Guanabara Bay Clean-up Programme interventions in both areas have contributed to perpetuate and reinforce existing patterns of spatial segregation, both between neighbourhoods of different socio-economic status and between...

  9. Household size and urban spatial change: end of an era?

    Directory of Open Access Journals (Sweden)

    Robert Sinclair

    2004-01-01

    Full Text Available A dominant demographic trend of the last few decades has been the declining size of householdsin Western industrialized countries. Following closely upon the Baby Boom, thedevelopment became a major topic of discussion for almost two decades. The basis for, andconsequences of, these changes have been well covered in the demographic literature, buttheir spatial implications have received less attention. Yet the, phenomenon has had a profoundspatial impact at every level of the urban system. Recent statistics indicate that householdsize continues to decline, but does so at a rapidly decreasing rate. The present paperconsiders the spatial repercussions of this trend. More specifically, the paper has three aims.(1 The paper summarizes and puts into present-day perspective, a volume of research conducteda decade ago upon the spatial impact of declining household size upon the U.S.urban system (Sinclair, 1991. (2 Considers more recent demographic developments, askingwhether the impact of declining household size upon the urban system is declining orcoming to a close, (3 Considers other demographic developments which might he takingthe place of declining household size in driving the urban system. In sum, the paper attemptsto answer the question. Is an era, which has signifycantly impacted the U.S. urbansystem, coming to a close?

  10. Spatiotemporal trends in extreme rainfall and temperature indices over Upper Tapi Basin, India

    Science.gov (United States)

    Sharma, Priyank J.; Loliyana, V. D.; S. R., Resmi; Timbadiya, P. V.; Patel, P. L.

    2017-12-01

    The flood risk across the globe is intensified due to global warming and subsequent increase in extreme temperature and precipitation. The long-term trends in extreme rainfall (1944-2013) and temperature (1969-2012) indices have been investigated at annual, seasonal, and monthly time scales using nonparametric Mann-Kendall (MK), modified Mann-Kendall (MMK), and Sen's slope estimator tests. The extreme rainfall and temperature indices, recommended by the Expert Team on Climate Change Detection Monitoring Indices (ETCCDMI), have been analyzed at finer spatial scales for trend detection. The results of trend analyses indicate decreasing trend in annual total rainfall, significant decreasing trend in rainy days, and increasing trend in rainfall intensity over the basin. The seasonal rainfall has been found to decrease for all the seasons except postmonsoon, which could affect the rain-fed agriculture in the basin. The 1- and 5-day annual maximum rainfalls exhibit mixed trends, wherein part of the basin experiences increasing trend, while other parts experience a decreasing trend. The increase in dry spells and concurrent decrease in wet spells are also observed over the basin. The extreme temperature indices revealed increasing trends in hottest and coldest days, while decreasing trends in coldest night are found over most parts of the basin. Further, the diurnal temperature range is also found to increase due to warming tendency in maximum temperature (T max) at a faster rate compared to the minimum temperature (T min). The increase in frequency and magnitude of extreme rainfall in the basin has been attributed to the increasing trend in maximum and minimum temperatures, reducing forest cover, rapid pace of urbanization, increase in human population, and thereby increase in the aerosol content in the atmosphere. The findings of the present study would significantly help in sustainable water resource planning, better decision-making for policy framework, and setting up

  11. CiteSpace II: Idiom Studies Development Trends

    Directory of Open Access Journals (Sweden)

    Wenyu Liu Ph.D.

    2013-06-01

    Full Text Available Idioms, frequently used in daily language, are a typical metaphorical language and may be a cue to uncover the universal language processing mechanism. For the purpose of better mastery of the trends and front of idioms studies, CiteSpace II, an application designed to detect and visualize the development process within a scientific field, is adopted for comprehensive literature review. It is found that (1 idioms studies have thrived since 1990s with American scholars contributing the most, especially those from University of California; (2 suppositions on idiom comprehension mechanism have been inspired by different scholars including Lakoff, Swinney and Gibbs; (3 the exploration of the neurological bases for idiom comprehension has become the pursuit of researchers across different domains.

  12. Distribution and trends of mercury in deciduous tree cores

    International Nuclear Information System (INIS)

    Siwik, Eden I.H.; Campbell, Linda M.; Mierle, Gregory

    2010-01-01

    The distribution of total mercury (THg) within common deciduous trees and the applicability of tree cores as biomonitors of historical environmental THg trends were assessed for both contaminated and reference sites around Kingston, Ontario. Samples were collected from Acer spp., Quercus spp. Populus spp. and Salix spp. Bark and wood THg concentrations were found to be highly correlated whereas soil and wood THg concentrations were not. There were no temporal relationships for THg in dated tree rings corresponding with any other known environmental Hg trends. The shoreline speciess, Populus and Salix spp., had the greatest bark and wood Hg concentrations reaching 18 ng/g, significantly higher than for inland trees Quercus and Acer spp. with maximum values of 7 and 1.2 ng/g for bark and wood respectively. While tree cores cannot be reliably used as temporal THg biomonitors, there is promise for tree species such as Populus spp and Salix spp as spatial indicators of local long-term Hg contamination. - Total mercury trends in several deciduous trees did not follow expected environmental trends. Shoreline species (willow and popular) had higher wood THg than inland species (oak and maple).

  13. Spatial autocorrelation analysis of tourist arrivals using municipal data: A Serbian example

    Directory of Open Access Journals (Sweden)

    Stankov Uglješa

    2017-01-01

    Full Text Available Spatial autocorrelation methodologies can be used to reveal patterns and temporal changes of different spatial variables, including tourism arrivals. The research adopts a GIS-based approach to spatially analyse tourist arrivals in Serbia, using Global Moran's I and Anselin's Local Moran's I statistics applied on the level of municipalities. To assess feasibility of this approach the article discusses spatial changes of tourist arrivals in order to identify potentially significant trends of interest for tourism development policy in Serbia. There is a significant spatial inequality in the distribution of tourism arrivals in Serbia that is not adequately addressed in tourism development plans. The results of global autocorrelation suggest the existence of low and decreasing spatial clustering for domestic tourist arrivals and high, relatively stable spatial clustering for international tourists. Local autocorrelation statistics revealed different of domestic and international tourism arrivals. In order to assess feasibility of this approach these results are discussed in their significance to tourism development policy in Serbia.

  14. [Spatial analysis of autumn-winter type scrub typhus in Shandong province, 2006-2014].

    Science.gov (United States)

    Yang, H; Bi, Z W; Kou, Z Q; Zheng, L; Zhao, Z T

    2016-05-01

    To discuss the spatial-temporal distribution and epidemic trends of autumn-winter type scrub typhus in Shandong province, and provide scientific evidence for further study for the prevention and control of the disease. The scrub typhus surveillance data during 2006-2014 were collected from Shandong Disease Reporting Information System. The data was analyzed by using software ArcGIS 9.3(ESRI Inc., Redlands, CA, USA), GeoDa 0.9.5-i and SatScan 9.1.1. The Moran' s I, log-likelihood ratio(LLR), relative risk(RR)were calculated and the incidence choropleth maps, local indicators of spatial autocorrelation cluster maps and space scaning cluster maps were drawn. A total of 4 453 scrub typhus cases were reported during 2006-2014, and the annual incidence increased with year. Among the 17 prefectures(municipality)in Shandong, 13 were affected by scrub typhus. The global Moran's I index was 0.501 5(Pscrub typhus in Shandong. Since 2006, the epidemic area of the disease has expanded and the number of high-risk areas has increased. Moreover, the eastward moving and periodically expanding trends of high-risk clusters were detected.

  15. Special study for the statistical evaluation of groundwater data trends. Final report

    International Nuclear Information System (INIS)

    1993-05-01

    Analysis of trends over time in the concentrations of chemicals in groundwater at Uranium Mill Tailings Remedial Action (UMTRA) Project sites can provide valuable information for monitoring the performance of disposal cells and the effectiveness of groundwater restoration activities. Random variation in data may obscure real trends or may produce the illusion of a trend where none exists, so statistical methods are needed to reliably detect and estimate trends. Trend analysis includes both trend detection and estimation. Trend detection uses statistical hypothesis testing and provides a yes or no answer regarding the existence of a trend. Hypothesis tests try to reach a balance between false negative and false positive conclusions. To quantify the magnitude of a trend, estimation is required. This report presents the statistical concepts that are necessary for understanding trend analysis. The types of patterns most likely to occur in UMTRA data sets are emphasized. Two general approaches to analyzing data for trends are proposed and recommendations are given to assist UMTRA Project staff in selecting an appropriate method for their site data. Trend analysis is much more difficult when data contain values less than the reported laboratory detection limit. The complications that arise are explained. This report also discusses the impact of data collection procedures on statistical trend methods and offers recommendations to improve the efficiency of the methods and reduce sampling costs. Guidance for determining how many sampling rounds might be needed by statistical methods to detect trends of various magnitudes is presented. This information could be useful in planning site monitoring activities

  16. Trends analysis of rainfall and rainfall extremes in Sarawak, Malaysia using modified Mann-Kendall test

    Science.gov (United States)

    Sa'adi, Zulfaqar; Shahid, Shamsuddin; Ismail, Tarmizi; Chung, Eun-Sung; Wang, Xiao-Jun

    2017-11-01

    This study assesses the spatial pattern of changes in rainfall extremes of Sarawak in recent years (1980-2014). The Mann-Kendall (MK) test along with modified Mann-Kendall (m-MK) test, which can discriminate multi-scale variability of unidirectional trend, was used to analyze the changes at 31 stations. Taking account of the scaling effect through eliminating the effect of autocorrelation, m-MK was employed to discriminate multi-scale variability of the unidirectional trends of the annual rainfall in Sarawak. It can confirm the significance of the MK test. The annual rainfall trend from MK test showed significant changes at 95% confidence level at five stations. The seasonal trends from MK test indicate an increasing rate of rainfall during the Northeast monsoon and a decreasing trend during the Southwest monsoon in some region of Sarawak. However, the m-MK test detected an increasing trend in annual rainfall only at one station and no significant trend in seasonal rainfall at any stations. The significant increasing trends of the 1-h maximum rainfall from the MK test are detected mainly at the stations located in the urban area giving concern to the occurrence of the flash flood. On the other hand, the m-MK test detected no significant trend in 1- and 3-h maximum rainfalls at any location. On the contrary, it detected significant trends in 6- and 72-h maximum rainfalls at a station located in the Lower Rajang basin area which is an extensive low-lying agricultural area and prone to stagnant flood. These results indicate that the trends in rainfall and rainfall extremes reported in Malaysia and surrounding region should be verified with m-MK test as most of the trends may result from scaling effect.

  17. Climate Risk and Vulnerability in the Caribbean and Gulf of Mexico Region: Interactions with Spatial Population and Land Cover Change

    Science.gov (United States)

    Chen, R. S.; Levy, M.; Baptista, S.; Adamo, S.

    2010-12-01

    Vulnerability to climate variability and change will depend on dynamic interactions between different aspects of climate, land-use change, and socioeconomic trends. Measurements and projections of these changes are difficult at the local scale but necessary for effective planning. New data sources and methods make it possible to assess land-use and socioeconomic changes that may affect future patterns of climate vulnerability. In this paper we report on new time series data sets that reveal trends in the spatial patterns of climate vulnerability in the Caribbean/Gulf of Mexico Region. Specifically, we examine spatial time series data for human population over the period 1990-2000, time series data on land use and land cover over 2000-2009, and infant mortality rates as a proxy for poverty for 2000-2008. We compare the spatial trends for these measures to the distribution of climate-related natural disaster risk hotspots (cyclones, floods, landslides, and droughts) in terms of frequency, mortality, and economic losses. We use these data to identify areas where climate vulnerability appears to be increasing and where it may be decreasing. Regions where trends and patterns are especially worrisome include coastal areas of Guatemala and Honduras.

  18. How well do regional or national Breeding Bird Survey data predict songbird population trends at an intact boreal site?

    Directory of Open Access Journals (Sweden)

    Craig S. Machtans

    2014-06-01

    Full Text Available A study to monitor boreal songbird trends was initiated in 1998 in a relatively undisturbed and remote part of the boreal forest in the Northwest Territories, Canada. Eight years of point count data were collected over the 14 years of the study, 1998-2011. Trends were estimated for 50 bird species using generalized linear mixed-effects models, with random effects to account for temporal (repeat sampling within years and spatial (stations within stands autocorrelation and variability associated with multiple observers. We tested whether regional and national Breeding Bird Survey (BBS trends could, on average, predict trends in our study area. Significant increases in our study area outnumbered decreases by 12 species to 6, an opposite pattern compared to Alberta (6 versus 15, respectively and Canada (9 versus 20. Twenty-two species with relatively precise trend estimates (precision to detect > 30% decline in 10 years; observed SE ≤ 3.7%/year showed nonsignificant trends, similar to Alberta (24 and Canada (20. Precision-weighted trends for a sample of 19 species with both reliable trends at our site and small portions of their range covered by BBS in Canada were, on average, more negative for Alberta (1.34% per year lower and for Canada (1.15% per year lower relative to Fort Liard, though 95% credible intervals still contained zero. We suggest that part of the differences could be attributable to local resource pulses (insect outbreak. However, we also suggest that the tendency for BBS route coverage to disproportionately sample more southerly, developed areas in the boreal forest could result in BBS trends that are not representative of range-wide trends for species whose range is centred farther north.

  19. Spatial and temporal variations in shallow wetland groundwater quality

    Science.gov (United States)

    Schot, Paul P.; Pieber, Simone M.

    2012-02-01

    SummaryWetlands worldwide are threatened by environmental change. Differences in groundwater composition is one of the factors affecting wetland terrestrial floristic biodiversity. However, few studies discuss variations in wetland groundwater composition. This study presents an analysis of local-scale spatial and short-term temporal variations in 15 groundwater composition parameters of the 7 km2 Naardermeer wetland nature reserve in The Netherlands. Data is available from a network of 35 groundwater wells with 2-4 filters each, at depths between 50 and 800 cm, which were sampled about monthly over a 1-year period, totalling 1042 chemical analysis from 103 filter screens. Relative standard deviations indicate large differences in variation between parameters. Largest spatial and temporal variations were found for nutrients (NO3-, PO43-, NH4+) and redox sensitive parameters (Fe, Mn), and lowest variations for macroions and SiO2. A horizontal zonation in groundwater concentrations has been found related to soil type and soil wetness, with largest horizontal decrease in NO3- and SO42-, and largest increase in Fe and SiO2, going in the groundwater flow direction from dry sandy soils to wet peat/clay soils. No clear horizontal patterns have been found for the macroions. Spatial zonations in the north-south direction and with depth are absent for all parameters. Spatial and temporal variations were found to be related. 3D-maps indicate highest temporal fluctuations at filter screens with lowest median concentrations for NO3-, SO42- and Fe, but the reverse pattern for SiO2. High temporal variations of nutrients and redox sensitive parameters could not be traced back to a seasonal trend. The spatial and temporal variability of groundwater quality parameters as presented in this study, together with their reported effects on different vegetation types, may be used to design efficient monitoring schemes by nature managers having set specific vegetation development targets

  20. Spatio-temporal trends and risk factors for Shigella from 2001 to 2011 in Jiangsu Province, People's Republic of China.

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    Fenyang Tang

    Full Text Available This study aimed to describe the spatial and temporal trends of Shigella incidence rates in Jiangsu Province, People's Republic of China. It also intended to explore complex risk modes facilitating Shigella transmission.County-level incidence rates were obtained for analysis using geographic information system (GIS tools. Trend surface and incidence maps were established to describe geographic distributions. Spatio-temporal cluster analysis and autocorrelation analysis were used for detecting clusters. Based on the number of monthly Shigella cases, an autoregressive integrated moving average (ARIMA model successfully established a time series model. A spatial correlation analysis and a case-control study were conducted to identify risk factors contributing to Shigella transmissions.The far southwestern and northwestern areas of Jiangsu were the most infected. A cluster was detected in southwestern Jiangsu (LLR = 11674.74, P<0.001. The time series model was established as ARIMA (1, 12, 0, which predicted well for cases from August to December, 2011. Highways and water sources potentially caused spatial variation in Shigella development in Jiangsu. The case-control study confirmed not washing hands before dinner (OR = 3.64 and not having access to a safe water source (OR = 2.04 as the main causes of Shigella in Jiangsu Province.Improvement of sanitation and hygiene should be strengthened in economically developed counties, while access to a safe water supply in impoverished areas should be increased at the same time.

  1. Spatializing 6,000 years of global urbanization from 3700 BC to AD 2000

    Science.gov (United States)

    Reba, Meredith; Reitsma, Femke; Seto, Karen C.

    2016-06-01

    How were cities distributed globally in the past? How many people lived in these cities? How did cities influence their local and regional environments? In order to understand the current era of urbanization, we must understand long-term historical urbanization trends and patterns. However, to date there is no comprehensive record of spatially explicit, historic, city-level population data at the global scale. Here, we developed the first spatially explicit dataset of urban settlements from 3700 BC to AD 2000, by digitizing, transcribing, and geocoding historical, archaeological, and census-based urban population data previously published in tabular form by Chandler and Modelski. The dataset creation process also required data cleaning and harmonization procedures to make the data internally consistent. Additionally, we created a reliability ranking for each geocoded location to assess the geographic uncertainty of each data point. The dataset provides the first spatially explicit archive of the location and size of urban populations over the last 6,000 years and can contribute to an improved understanding of contemporary and historical urbanization trends.

  2. Spatial Evolution of Producer Service Sectors and Its Influencing Factors in Cities: A Case Study of Hangzhou, China

    Directory of Open Access Journals (Sweden)

    Yizhou Wu

    2018-03-01

    Full Text Available Producer service industries are an important feature in the current development of a metropolis. Researchers from different countries are increasingly concerned about location changes and the motives of producer service sectors in cities. Given the rapid development of producer service sectors in developing countries, this study examines changes in the distribution of producer service sectors over the past decade and factors influencing them in a case study using the city of Hangzhou in China. Results show that Hangzhou’s producer service sector is still mainly concentrated in the central business district (CBD. However, a distinct trend of diffusion to suburban areas was observed, which formed several secondary clusters on the periphery of the city. Locations of the CBD, sub-centers, and professional clusters of producer service sectors established by the government are the most important factors that affect the spatial distribution of producer service sectors. The main influencing factors for the spatial evolution of producer service sectors are: (1 the high development cost and residential suburbanization of the central areas of the city promote the development of producer service sectors toward the periphery; (2 city planning has guided the clustering of producer service sectors on the city’s CBD and secondary city centers; (3 city renewal has provided personalized and diversified development space for producer service sectors; (4 incentive policies introduced by the government, such as rentals, and taxes have enhanced the orderly aggregation of producer service sectors.

  3. Trend Change Detection in NDVI Time Series: Effects of Inter-Annual Variability and Methodology

    Science.gov (United States)

    Forkel, Matthias; Carvalhais, Nuno; Verbesselt, Jan; Mahecha, Miguel D.; Neigh, Christopher S.R.; Reichstein, Markus

    2013-01-01

    Changing trends in ecosystem productivity can be quantified using satellite observations of Normalized Difference Vegetation Index (NDVI). However, the estimation of trends from NDVI time series differs substantially depending on analyzed satellite dataset, the corresponding spatiotemporal resolution, and the applied statistical method. Here we compare the performance of a wide range of trend estimation methods and demonstrate that performance decreases with increasing inter-annual variability in the NDVI time series. Trend slope estimates based on annual aggregated time series or based on a seasonal-trend model show better performances than methods that remove the seasonal cycle of the time series. A breakpoint detection analysis reveals that an overestimation of breakpoints in NDVI trends can result in wrong or even opposite trend estimates. Based on our results, we give practical recommendations for the application of trend methods on long-term NDVI time series. Particularly, we apply and compare different methods on NDVI time series in Alaska, where both greening and browning trends have been previously observed. Here, the multi-method uncertainty of NDVI trends is quantified through the application of the different trend estimation methods. Our results indicate that greening NDVI trends in Alaska are more spatially and temporally prevalent than browning trends. We also show that detected breakpoints in NDVI trends tend to coincide with large fires. Overall, our analyses demonstrate that seasonal trend methods need to be improved against inter-annual variability to quantify changing trends in ecosystem productivity with higher accuracy.

  4. 5th Regional Study on Cadastre and Spatial Data Infrastructure

    Directory of Open Access Journals (Sweden)

    Ivica Skender

    2012-12-01

    Full Text Available In the aftermath of the 5th Regional Conference on Cadastre and Spatial Data Infrastructure (Banja Luka and Laktaši, Bosnia and Herzegovina, June 6–8, 2012, the Republic Authority for Geodetic and Property Affairs of the Republic of Srpska and the Federal Administration for Geodetic and Real Property Affairs published the 5th Regional Study on Cadastre and Spatial Data Infrastructure. The study was produced in the frame of the Project INSPIRATION – Spatial Data Infrastructure in the Western Balkans, which is being realized for the benefit and with cooperation of representatives of eight geodetic administrations in the region (Albania, Bosnia and Herzegovina, Montenegro, Croatia, Kosovo, Macedonia, Serbia by consortium led by German company GFA of Hamburg, in cooperation with GDi GISDATA of Zagreb, experts from the Austrian Environmental Agency and German company con terra GmbH and financed from the European Union IPA funding programme for 2010.

  5. Spatial Temporal Modelling of Particulate Matter for Health Effects Studies

    Science.gov (United States)

    Hamm, N. A. S.

    2016-10-01

    Epidemiological studies of the health effects of air pollution require estimation of individual exposure. It is not possible to obtain measurements at all relevant locations so it is necessary to predict at these space-time locations, either on the basis of dispersion from emission sources or by interpolating observations. This study used data obtained from a low-cost sensor network of 32 air quality monitoring stations in the Dutch city of Eindhoven, which make up the ILM (innovative air (quality) measurement system). These stations currently provide PM10 and PM2.5 (particulate matter less than 10 and 2.5 m in diameter), aggregated to hourly means. The data provide an unprecedented level of spatial and temporal detail for a city of this size. Despite these benefits the time series of measurements is characterized by missing values and noisy values. In this paper a space-time analysis is presented that is based on a dynamic model for the temporal component and a Gaussian process geostatistical for the spatial component. Spatial-temporal variability was dominated by the temporal component, although the spatial variability was also substantial. The model delivered accurate predictions for both isolated missing values and 24-hour periods of missing values (RMSE = 1.4 μg m-3 and 1.8 μg m-3 respectively). Outliers could be detected by comparison to the 95% prediction interval. The model shows promise for predicting missing values, outlier detection and for mapping to support health impact studies.

  6. Spatial relationships and movement patterns of the air cargo industry in airport regions

    Directory of Open Access Journals (Sweden)

    Petrus J. van V. Coetzee

    2017-05-01

    Full Text Available Background: During the past few years, with the increase in air traffic and the expansion of airports, very few industries had such a large spatial development and movement impact as that of airport-related clusters or airport regions. Although much research was done on the various impacts of the airport industry, very little research was done on the air cargo industry in airport regions. Objectives: This article specifically explored the unique spatial relationships, impacts, trends and movement patterns of the air cargo industry within a typical airport region. Method: The article focused on the OR Tambo International Airport in Gauteng, South Africa, as a case study and was informed by an extensive quantitative spatial and land use analysis and modelling of the study area. Results: The article presented findings and insights on the movement patterns and relationships between (1 the airport facility and (2 the spatial configuration of air cargo industries in the particular airport region. These findings also provided some framework for a possible spatial model and guideline that could assist in steering and managing development and movement patterns in airport regions. Conclusion: The article provided new insights and understanding on the spatial dynamics of airport regions and the air cargo industry, ultimately addressing some gaps in this knowledge field. The article in the end highlighted the need for a different and novel approach to the planning and management of the air cargo industry in airport regions and a basis for further research.

  7. Trends in stream nitrogen concentrations for forested reference catchments across the USA

    International Nuclear Information System (INIS)

    Argerich, A; Greathouse, E; Johnson, S L; Sebestyen, S D; Rhoades, C C; Knoepp, J D; Adams, M B; Likens, G E; Campbell, J L; McDowell, W H; Scatena, F N; Ice, G G

    2013-01-01

    To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among sites across the USA. We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations. At a subset of the catchments, we found that the length and period of analysis influenced whether trends were positive, negative or non-significant. Trends also differed among neighboring catchments within several Experimental Forests, suggesting the importance of catchment-specific factors in determining nutrient exports. Over the longest time periods, trends were more consistent among catchments within sites, although there are fewer long-term records for analysis. These findings highlight the critical value of long-term, uninterrupted stream chemistry monitoring at a network of sites across the USA to elucidate patterns of change in nutrient concentrations at minimally disturbed forested sites. (letter)

  8. Children's Spatial Thinking: Does Talk about the Spatial World Matter?

    Science.gov (United States)

    Pruden, Shannon M.; Levine, Susan C.; Huttenlocher, Janellen

    2011-01-01

    In this paper we examine the relations between parent spatial language input, children's own production of spatial language, and children's later spatial abilities. Using a longitudinal study design, we coded the use of spatial language (i.e. words describing the spatial features and properties of objects; e.g. big, tall, circle, curvy, edge) from…

  9. Integrated flood disaster management and spatial information : Case studies of Netherlands and India

    NARCIS (Netherlands)

    Ghawana, T. (T.); Kaur, A. (A.); Neuvel, J.M.M. (J.M.M.); Ziatanova, Z. (Z.)

    2014-01-01

    Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XL-8, 147-154, 2014www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XL-8/147/2014/doi:10.5194/isprsarchives-XL-8-147-2014Integrated flood disaster management and spatial information: Case studies ofNetherlands and IndiaS. Zlatanova1, T.

  10. The influence of caffeine on spatial-selective attention : an event-related potential study

    NARCIS (Netherlands)

    de Ruiter, MB; Snel, J; Lorist, MM; Ruijter, J

    2000-01-01

    Objectives: Following the indications of previous studies that caffeine might have a specific effect on the processing of spatial information compared with other types of information, the present study investigated the influence of caffeine on an often used spatial-selective attention task. Methods:

  11. Recent trends in paralytic shellfish toxins in Puget Sound, relationships to climate, and capacity for prediction of toxic events

    Science.gov (United States)

    Stephanie K. Moore; Nathan J. Mantua; Barbara M. Hickey; Vera L. Trainer

    2009-01-01

    Temporal and spatial trends in paralytic shellfish toxins (PSTs) in Puget Sound shellfish and their relationships with climate are investigated using long-term monitoring data since 1957. Data are selected for trend analyses based on the sensitivity of shellfish species to PSTs and their depuration rates, and the frequency of sample collection at individual sites....

  12. Factors challenging our ability to detect long-term trends in ocean chlorophyll

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    C. Beaulieu

    2013-04-01

    Full Text Available Global climate change is expected to affect the ocean's biological productivity. The most comprehensive information available about the global distribution of contemporary ocean primary productivity is derived from satellite data. Large spatial patchiness and interannual to multidecadal variability in chlorophyll a concentration challenges efforts to distinguish a global, secular trend given satellite records which are limited in duration and continuity. The longest ocean color satellite record comes from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS, which failed in December 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS ocean color sensors are beyond their originally planned operational lifetime. Successful retrieval of a quality signal from the current Visible Infrared Imager Radiometer Suite (VIIRS instrument, or successful launch of the Ocean and Land Colour Instrument (OLCI expected in 2014 will hopefully extend the ocean color time series and increase the potential for detecting trends in ocean productivity in the future. Alternatively, a potential discontinuity in the time series of ocean chlorophyll a, introduced by a change of instrument without overlap and opportunity for cross-calibration, would make trend detection even more challenging. In this paper, we demonstrate that there are a few regions with statistically significant trends over the ten years of SeaWiFS data, but at a global scale the trend is not large enough to be distinguished from noise. We quantify the degree to which red noise (autocorrelation especially challenges trend detection in these observational time series. We further demonstrate how discontinuities in the time series at various points would affect our ability to detect trends in ocean chlorophyll a. We highlight the importance of maintaining continuous, climate-quality satellite data records for climate-change detection and attribution studies.

  13. Spatial and Semantic Processing between Audition and Vision: An Event-Related Potential Study

    Directory of Open Access Journals (Sweden)

    Xiaoxi Chen

    2011-10-01

    Full Text Available Using a crossmodal priming paradigm, this study investigated how the brain bound the spatial and semantic features in multisensory processing. The visual stimuli (pictures of animals were presented after the auditory stimuli (sounds of animals, and the stimuli from different modalities may match spatially (or semantically or not. Participants were required to detect the head orientation of the visual target (an oddball paradigm. The event-related potentials (ERPs to the visual stimuli was enhanced by spatial attention (150–170 ms irrespectively of semantic information. The early crossmodal attention effect for the visual stimuli was more negative in the spatial-congruent condition than in the spatial-incongruent condition. By contrast, the later effects of spatial ERPs were significant only for the semantic- congruent condition (250–300 ms. These findings indicated that spatial attention modulated early visual processing, and semantic and spatial features were simultaneously used to orient attention and modulate later processing stages.

  14. Recovery trends in marine mammal populations.

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    Anna M Magera

    Full Text Available Marine mammals have greatly benefitted from a shift from resource exploitation towards conservation. Often lauded as symbols of conservation success, some marine mammal populations have shown remarkable recoveries after severe depletions. Others have remained at low abundance levels, continued to decline, or become extinct or extirpated. Here we provide a quantitative assessment of (1 publicly available population-level abundance data for marine mammals worldwide, (2 abundance trends and recovery status, and (3 historic population decline and recent recovery. We compiled 182 population abundance time series for 47 species and identified major data gaps. In order to compare across the largest possible set of time series with varying data quality, quantity and frequency, we considered an increase in population abundance as evidence of recovery. Using robust log-linear regression over three generations, we were able to classify abundance trends for 92 spatially non-overlapping populations as Significantly Increasing (42%, Significantly Decreasing (10%, Non-Significant Change (28% and Unknown (20%. Our results were comparable to IUCN classifications for equivalent species. Among different groupings, pinnipeds and other marine mammals (sirenians, polar bears and otters showed the highest proportion of recovering populations, likely benefiting from relatively fast life histories and nearshore habitats that provided visibility and protective management measures. Recovery was less frequent among cetaceans, but more common in coastal than offshore populations. For marine mammals with available historical abundance estimates (n = 47, larger historical population declines were associated with low or variable recent recoveries so far. Overall, our results show that many formerly depleted marine mammal populations are recovering. However, data-deficient populations and those with decreasing and non-significant trends require attention. In particular

  15. Spatial correlations, clustering and percolation-like transitions in homicide crimes

    Science.gov (United States)

    Alves, L. G. A.; Lenzi, E. K.; Mendes, R. S.; Ribeiro, H. V.

    2015-07-01

    The spatial dynamics of criminal activities has been recently studied through statistical physics methods; however, models and results have been focusing on local scales (city level) and much less is known about these patterns at larger scales, e.g. at a country level. Here we report on a characterization of the spatial dynamics of the homicide crimes along the Brazilian territory using data from all cities (˜5000) in a period of more than thirty years. Our results show that the spatial correlation function in the per capita homicides decays exponentially with the distance between cities and that the characteristic correlation length displays an acute increasing trend in the latest years. We also investigate the formation of spatial clusters of cities via a percolation-like analysis, where clustering of cities and a phase-transition-like behavior describing the size of the largest cluster as a function of a homicide threshold are observed. This transition-like behavior presents evolutive features characterized by an increasing in the homicide threshold (where the transitions occur) and by a decreasing in the transition magnitudes (length of the jumps in the cluster size). We believe that our work sheds new light on the spatial patterns of criminal activities at large scales, which may contribute for better political decisions and resources allocation as well as opens new possibilities for modeling criminal activities by setting up fundamental empirical patterns at large scales.

  16. Spatial Visualization ability improves with and without studying Technical Drawing.

    Science.gov (United States)

    Contreras, María José; Escrig, Rebeca; Prieto, Gerardo; Elosúa, M Rosa

    2018-03-27

    The results of several studies suggest that spatial ability can be improved through direct training with tasks similar to those integrated in the tests used to measure the ability. However, there is a greater interest in analyzing the effectiveness of indirect training such as games or of learning subjects that involve spatial processes to a certain extent. Thus, the objective of the present study was to analyze whether the indirect training in Technical Drawing improved the Spatial Visualization ability of Architecture students. For this purpose, a group of students enrolled in Fundamentals of Architecture were administered two tests, a Spatial Visualization task and an Abstract Reasoning task, at the beginning and the end of a semester, after having received training through the subjects "Technical Drawing I: Geometry and Perception" and "Projects I." The results of this group were compared with those of a control group of students enrolled in a Mathematics degree, who were also pre-post evaluated but had not received the training in Technical Drawing. The study showed a significant pre-post improvement in both, Visualization and reasoning. However, this improvement occurred in both groups, thereby concluding that this improvement was not due to indirect training. Furthermore, no significant differences were found between men and women in any of the groups or conditions. These results clarify those of an earlier study where improvement in Visualization after training in Technical Drawing was found but did not include a comparison with a control condition. The control condition has proved to be important in order to consider the limitations of the effect of Technical Drawing on said improvement.

  17. Spatially explicit trends in the global conservation status of vertebrates.

    Science.gov (United States)

    Rodrigues, Ana S L; Brooks, Thomas M; Butchart, Stuart H M; Chanson, Janice; Cox, Neil; Hoffmann, Michael; Stuart, Simon N

    2014-01-01

    The world's governments have committed to preventing the extinction of threatened species and improving their conservation status by 2020. However, biodiversity is not evenly distributed across space, and neither are the drivers of its decline, and so different regions face very different challenges. Here, we quantify the contribution of regions and countries towards recent global trends in vertebrate conservation status (as measured by the Red List Index), to guide action towards the 2020 target. We found that>50% of the global deterioration in the conservation status of birds, mammals and amphibians is concentrated in nations (e.g. Cook Islands, Fiji, Mauritius, Seychelles, and Tonga), have achieved net improvements. Per capita wealth does not explain these patterns, with two of the richest countries - United States and Australia - fairing conspicuously poorly. Different countries were affected by different combinations of threats. Reducing global rates of biodiversity loss will require investment in the regions and countries with the highest responsibility for the world's biodiversity, focusing on conserving those species and areas most in peril and on reducing the drivers with the highest impacts.

  18. The study on the spatial-temporal changes of land use pattern in eastern Sichuan basin based on RS/GIS

    Science.gov (United States)

    Sun, Siqi; Xiao, Yi; Guo, Luo

    2018-02-01

    Eastern Sichuan Basin is one of the areas sensitive to global climate change. Due to impacts from human disturbance, the farmland in the study area has been degrading, and the desertification of land has been expanding rapidly. Based on the data of Landsat TM/ETM image in 1990, 1995, 2000, 2005 and 2010, this thesis analysed the spatial characteristics and dynamic trends of land use pattern in eastern Sichuan basin using software for remote sense and geographical information system. The driving factors of land-use change in study area were also discussed. The results indicated that: (i) the area of farmland has significantly decreased because of degradation and conversion from grassland into building land; (ii) farmland patches have changed into fragmented and isolated ones; (iii) the main landscapes in study area, are farmland and forests; (iv) land-use change is significantly associated with the human activities. This study provides a strong theoretical and technical basis for the policy-making of environmental protection and management in Eastern Sichuan Basin of Sichuan Province in china.

  19. Remanence of lead pollution in an urban river system: a multi-scale temporal and spatial study in the Seine River basin, France.

    Science.gov (United States)

    Ayrault, S; Le Pape, P; Evrard, O; Priadi, C R; Quantin, C; Bonté, P; Roy-Barman, M

    2014-03-01

    Total lead (Pb) concentration and Pb isotopic ratio ((206)Pb/(20)7Pb) were determined in 140 samples from the Seine River basin (France), covering a period of time from 1945 to 2011 and including bed sediments (bulk and size fractionated samples), suspended particulate matter (SPM), sediment cores, and combined sewer overflow (CSO) particulate matter to constrain the spatial and temporal variability of the lead sources at the scale of the contaminated Seine River basin. A focus on the Orge River subcatchment, which exhibits a contrasted land-use pattern, allows documenting the relation between hydrodynamics, urbanization, and contamination sources. The study reveals that the Pb contamination due to leaded gasoline that peaked in the 1980s has a very limited impact in the river nowadays. In the upstream Seine River, the isotopic ratio analysis suggests a pervasive contamination which origin (coal combustion and/or gasoline lead) should be clarified. The current SPM contamination trend follows the urbanization/industrialization spatial trend. Downstream of Paris, the lead from historical use originating from the Rio Tinto mine, Spain ((206)Pb/(207)Pb=1.1634 ± 0.0001) is the major Pb source. The analysis of the bed sediments (bulk and grain size fractionated) highlights the diversity of the anthropogenic lead sources in relation with the diversity of the human activities that occurred in this basin over the years. The "urban" source, defined by waste waters including the CSO samples ((206)Pb/(207)Pb=1.157 ± 0.003), results of a thorough mixing of leaded gasoline with "historical" lead over the years. Finally, a contamination mixing scheme related to hydrodynamics is proposed.

  20. Observation-Driven Estimation of the Spatial Variability of 20th Century Sea Level Rise

    Science.gov (United States)

    Hamlington, B. D.; Burgos, A.; Thompson, P. R.; Landerer, F. W.; Piecuch, C. G.; Adhikari, S.; Caron, L.; Reager, J. T.; Ivins, E. R.

    2018-03-01

    Over the past two decades, sea level measurements made by satellites have given clear indications of both global and regional sea level rise. Numerous studies have sought to leverage the modern satellite record and available historic sea level data provided by tide gauges to estimate past sea level rise, leading to several estimates for the 20th century trend in global mean sea level in the range between 1 and 2 mm/yr. On regional scales, few attempts have been made to estimate trends over the same time period. This is due largely to the inhomogeneity and quality of the tide gauge network through the 20th century, which render commonly used reconstruction techniques inadequate. Here, a new approach is adopted, integrating data from a select set of tide gauges with prior estimates of spatial structure based on historical sea level forcing information from the major contributing processes over the past century. The resulting map of 20th century regional sea level rise is optimized to agree with the tide gauge-measured trends, and provides an indication of the likely contributions of different sources to regional patterns. Of equal importance, this study demonstrates the sensitivities of this regional trend map to current knowledge and uncertainty of the contributing processes.

  1. Differentiating Spatial Memory from Spatial Transformations

    Science.gov (United States)

    Street, Whitney N.; Wang, Ranxiao Frances

    2014-01-01

    The perspective-taking task is one of the most common paradigms used to study the nature of spatial memory, and better performance for certain orientations is generally interpreted as evidence of spatial representations using these reference directions. However, performance advantages can also result from the relative ease in certain…

  2. Analysis of Spatial Pattern and Influencing Factors of E-Commerce

    Science.gov (United States)

    Zhang, Y.; Chen, J.; Zhang, S.

    2017-09-01

    This paper aims to study the relationship between e-commerce development and geographical characteristics using data of e-commerce, economy, Internet, express delivery and population from 2011 to 2015. Moran's I model and GWR model are applied to analyze the spatial pattern of E-commerce and its influencing factors. There is a growth trend of e-commerce from west to east, and it is obvious to see that e-commerce development has a space-time clustering, especially around the Yangtze River delta. The comprehensive factors caculated through PCA are described as fundamental social productivity, resident living standard and population sex structure. The first two factors have positive correlation with e-commerce, and the intensity of effect increases yearly. However, the influence of population sex structure on the E-commerce development is not significant. Our results suggest that the clustering of e-commerce has a downward trend and the impact of driving factors on e-commerce is observably distinct from year to year in space.

  3. A Comparative Study of Trade Relations and the Spatial-Temporal Evolution of Geo-Economy between China and Vietnam

    Directory of Open Access Journals (Sweden)

    Teng Ma

    2017-06-01

    Full Text Available With the increasing economic importance of the Asia-Pacific Region, the economic interdependence among countries in the region has gradually enhanced. With the continuous opening up of the two countries, Sino-Vietnamese economic relations have also been deepened. However, the export trade between Vietnam and China has been competitive. China and Vietnam seek to dominate or join an agreement that is conducive to their own trade, which also exacerbates the trade competition between the two countries. This paper compares China and Vietnam and analyzes their foreign trade data from 2005 to 2014. By analyzing the competitiveness of export commodities, the trade division effect and spatio-temporal changes of the geo-economic relationship in the Asia-Pacific Region, this study explores Sino-Vietnamese trade relations and compares the pattern of geo-economic evolution between the two countries. The findings show that China and Vietnam have similarities and substitutability in textiles, apparel and footwear in terms of commodity structure. There is already a trade diversion effect between Vietnam and China on these commodities, but it is not substantial. From a geographic perspective, China’s geo-economic relations in the Pacific Rim present an increasingly dispersed trend. However, the spatial pattern of Vietnam’s geo-economy has maintained a low-level and stable spatial agglomeration over the last decade.

  4. Trends in birth asphyxia, obstetric interventions and perinatal mortality among term singletons: a nationwide cohort study

    NARCIS (Netherlands)

    Ensing, Sabine; Abu-Hanna, Ameen; Schaaf, Jelle M.; Mol, Ben Willem J.; Ravelli, Anita C. J.

    2015-01-01

    The objective of the present study is to investigate trends in birth asphyxia and perinatal mortality in the Netherlands over the last decade. A nationwide cohort study among women with a term singleton pregnancy. We assessed trends in birth asphyxia in relation to obstetric interventions for fetal

  5. Flipped Classroom Research and Trends from Different Fields of Study

    Science.gov (United States)

    Zainuddin, Zamzami; Halili, Siti Hajar

    2016-01-01

    This paper aims to analyse the trends and contents of flipped classroom research based on 20 articles that report on flipped learning classroom initiatives from 2013-2015. The content analysis was used as a methodology to investigate methodologies, area of studies, technology tools or online platforms, the most frequently used keywords and works…

  6. Spatial trends and impairment assessment of mercury in sport fish in the Sacramento-San Joaquin Delta watershed

    International Nuclear Information System (INIS)

    Melwani, A.R.; Bezalel, S.N.; Hunt, J.A.; Grenier, J.L.; Ichikawa, G.; Heim, W.; Bonnema, A.; Foe, C.; Slotton, D.G.; Davis, J.A.

    2009-01-01

    A three-year study was conducted to examine mercury in sport fish from the Sacramento-San Joaquin Delta. More than 4000 fish from 31 species were collected and analyzed for total mercury in individual muscle filets. Largemouth bass and striped bass were the most contaminated, averaging 0.40 μg/g, while redear sunfish, bluegill and rainbow trout exhibited the lowest (<0.15 μg/g) concentrations. Spatial variation in mercury was evaluated with an analysis of covariance model, which accounted for variability due to fish size and regional hydrology. Significant regional differences in mercury were apparent in size-standardized largemouth bass, with concentrations on the Cosumnes and Mokelumne rivers significantly higher than the central and western Delta. Significant prey-predator mercury correlations were also apparent, which may explain a significant proportion of the spatial variation in the watershed. - Regional differences in sport fish mercury were found in the Sacramento-San Joaquin Delta.

  7. Accounting for and predicting the influence of spatial autocorrelation in water quality modeling

    Science.gov (United States)

    Miralha, L.; Kim, D.

    2017-12-01

    Although many studies have attempted to investigate the spatial trends of water quality, more attention is yet to be paid to the consequences of considering and ignoring the spatial autocorrelation (SAC) that exists in water quality parameters. Several studies have mentioned the importance of accounting for SAC in water quality modeling, as well as the differences in outcomes between models that account for and ignore SAC. However, the capacity to predict the magnitude of such differences is still ambiguous. In this study, we hypothesized that SAC inherently possessed by a response variable (i.e., water quality parameter) influences the outcomes of spatial modeling. We evaluated whether the level of inherent SAC is associated with changes in R-Squared, Akaike Information Criterion (AIC), and residual SAC (rSAC), after accounting for SAC during modeling procedure. The main objective was to analyze if water quality parameters with higher Moran's I values (inherent SAC measure) undergo a greater increase in R² and a greater reduction in both AIC and rSAC. We compared a non-spatial model (OLS) to two spatial regression approaches (spatial lag and error models). Predictor variables were the principal components of topographic (elevation and slope), land cover, and hydrological soil group variables. We acquired these data from federal online sources (e.g. USGS). Ten watersheds were selected, each in a different state of the USA. Results revealed that water quality parameters with higher inherent SAC showed substantial increase in R² and decrease in rSAC after performing spatial regressions. However, AIC values did not show significant changes. Overall, the higher the level of inherent SAC in water quality variables, the greater improvement of model performance. This indicates a linear and direct relationship between the spatial model outcomes (R² and rSAC) and the degree of SAC in each water quality variable. Therefore, our study suggests that the inherent level of

  8. Spatiotemporal Dynamics and Spatial Determinants of Urban Growth in Suzhou, China

    Directory of Open Access Journals (Sweden)

    Ling Zhang

    2017-03-01

    Full Text Available This paper analyzes the spatiotemporal dynamics of urban growth and models its spatial determinants in China through a case study of Suzhou, a rapidly industrializing and globalizing city. We conducted spatial analysis on land use data derived from multi-temporal remote sensing images of Suzhou from 1986 to 2008. Three urban growth types, namely infilling, edge-expansion, and leapfrog, were identified. We used landscape metrics to quantify the temporal trend of urban growth in Suzhou. During these 22 years, Suzhou’s urbanization changed from bottom-up rural urbanization to city-based top-down urban expansion. The underlying mechanism changed from TVE (town village enterprise driven rural industrialization to FDI (foreign direct investment driven development zone fever. Furthermore, we employed both global and local logistic regressions to model the probability of urban land conversion against a set of spatial variables. The global logistic regression model found the significance of proximity, neighborhood conditions, and socioeconomic factors. The logistic geographically weighted regression (GWR model improved the global regression model with better model goodness-of-fit and higher prediction accuracy. More importantly, the local parameter estimates of variables enabled us to exam spatial variations of the influences of variables on urban growth in Suzhou.

  9. Socio-demographic, ecological factors and dengue infection trends in Australia.

    Science.gov (United States)

    Akter, Rokeya; Naish, Suchithra; Hu, Wenbiao; Tong, Shilu

    2017-01-01

    Dengue has been a major public health concern in Australia. This study has explored the spatio-temporal trends of dengue and potential socio- demographic and ecological determinants in Australia. Data on dengue cases, socio-demographic, climatic and land use types for the period January 1999 to December 2010 were collected from Australian National Notifiable Diseases Surveillance System, Australian Bureau of Statistics, Australian Bureau of Meteorology, and Australian Bureau of Agricultural and Resource Economics and Sciences, respectively. Descriptive and linear regression analyses were performed to observe the spatio-temporal trends of dengue, socio-demographic and ecological factors in Australia. A total of 5,853 dengue cases (both local and overseas acquired) were recorded across Australia between January 1999 and December 2010. Most the cases (53.0%) were reported from Queensland, followed by New South Wales (16.5%). Dengue outbreak was highest (54.2%) during 2008-2010. A highest percentage of overseas arrivals (29.9%), households having rainwater tanks (33.9%), Indigenous population (27.2%), separate houses (26.5%), terrace house types (26.9%) and economically advantage people (42.8%) were also observed during 2008-2010. Regression analyses demonstrate that there was an increasing trend of dengue incidence, potential socio-ecological factors such as overseas arrivals, number of households having rainwater tanks, housing types and land use types (e.g. intensive uses and production from dryland agriculture). Spatial variation of socio-demographic factors was also observed in this study. In near future, significant increase of temperature was also projected across Australia. The projected increased temperature as well as increased socio-ecological trend may pose a future threat to the local transmission of dengue in other parts of Australia if Aedes mosquitoes are being established. Therefore, upgraded mosquito and disease surveillance at different ports should

  10. DEFINING SPATIAL VIOLENCE. BUCHAREST AS A STUDY CASE

    Directory of Open Access Journals (Sweden)

    Celia GHYKA

    2015-05-01

    Full Text Available The paper looks at the spatial manifestations of violence, aiming to define the category of spatial violence by focusing on the recent urban history of Bucharest; it establishes links with the longer history of natural and inflicted disasters that defined the city, and it explores the spatial, urban, social and symbolical conflicts that occured during the last 25 years, pointing at their consequences on the social and urban substance of the city.

  11. A Spatially Resolved Study of the GRB 020903 Host Galaxy

    Science.gov (United States)

    Thorp, Mallory D.; Levesque, Emily M.

    2018-03-01

    GRB 020903 is a long-duration gamma-ray burst with a host galaxy close enough and extended enough for spatially resolved observations, making it one of less than a dozen GRBs where such host studies are possible. GRB 020903 lies in a galaxy host complex that appears to consist of four interacting components. Here we present the results of spatially resolved spectroscopic observations of the GRB 020903 host. By taking observations at two different position angles, we were able to obtain optical spectra (3600–9000 Å) of multiple regions in the galaxy. We confirm redshifts for three regions of the host galaxy that match that of GRB 020903. We measure the metallicity of these regions, and find that the explosion site and the nearby star-forming regions both have comparable subsolar metallicities. We conclude that, in agreement with past spatially resolved studies of GRBs, the GRB explosion site is representative of the host galaxy as a whole rather than localized in a metal-poor region of the galaxy.

  12. Trends and periodicity of daily temperature and precipitation extremes during 1960-2013 in Hunan Province, central south China

    Science.gov (United States)

    Chen, Ajiao; He, Xinguang; Guan, Huade; Cai, Yi

    2018-04-01

    In this study, the trends and periodicity in climate extremes are examined in Hunan Province over the period 1960-2013 on the basis of 27 extreme climate indices calculated from daily temperature and precipitation records at 89 meteorological stations. The results show that in the whole province, temperature extremes exhibit a warming trend with more than 50% stations being statistically significant for 7 out of 16 temperature indices, and the nighttime temperature increases faster than the daytime temperature at the annual scale. The changes in most extreme temperature indices show strongly coherent spatial patterns. Moreover, the change rates of almost all temperature indices in north Hunan are greater than those of other regions. However, the statistically significant changes in indices of extreme precipitation are observed at fewer stations than in extreme temperature indices, forming less spatially coherent patterns. Positive trends in indices of extreme precipitation show that the amount and intensity of extreme precipitation events are generally increasing in both annual and seasonal scales, whereas the significant downward trend in consecutive wet days indicates that the precipitation becomes more even over the study period. Analysis of changes in probability distributions of extreme indices for 1960-1986 and 1987-2013 also demonstrates a remarkable shift toward warmer condition and increasing tendency in the amount and intensity of extreme precipitation during the past decades. The variations in extreme climate indices exhibit inconstant frequencies in the wavelet power spectrum. Among the 16 temperature indices, 2 of them show significant 1-year periodic oscillation and 7 of them exhibit significant 4-year cycle during some certain periods. However, significant periodic oscillations can be found in all of the precipitation indices. Wet-day precipitation and three absolute precipitation indices show significant 1-year cycle and other seven provide

  13. Spring onset variations and long-term trends from new hemispheric-scale products and remote sensing

    Science.gov (United States)

    Dye, D. G.; Li, X.; Ault, T.; Zurita-Milla, R.; Schwartz, M. D.

    2015-12-01

    Spring onset is commonly characterized by plant phenophase changes among a variety of biophysical transitions and has important implications for natural and man-managed ecosystems. Here, we present a new integrated analysis of variability in gridded Northern Hemisphere spring onset metrics. We developed a set of hemispheric temperature-based spring indices spanning 1920-2013. As these were derived solely from meteorological data, they are used as a benchmark for isolating the climate system's role in modulating spring "green up" estimated from the annual cycle of normalized difference vegetation index (NDVI). Spatial patterns of interannual variations, teleconnections, and long-term trends were also analyzed in all metrics. At mid-to-high latitudes, all indices exhibit larger variability at interannual to decadal time scales than at spatial scales of a few kilometers. Trends of spring onset vary across space and time. However, compared to long-term trend, interannual to decadal variability generally accounts for a larger portion of the total variance in spring onset timing. Therefore, spring onset trends identified from short existing records may be aliased by decadal climate variations due to their limited temporal depth, even when these records span the entire satellite era. Based on our findings, we also demonstrated that our indices have skill in representing ecosystem-level spring phenology and may have important implications in understanding relationships between phenology, atmosphere dynamics and climate variability.

  14. Monitor of spatial plans. Feasibility study

    International Nuclear Information System (INIS)

    Bollen, M.J.S.; Ritsema van Eck, J.; Farjon, J.M.J.

    2008-01-01

    The national government needs assessments of consequences of building projects in relation to spatial policy objectives such as the prevention of urban sprawl or the development of landscape qualities. Normally the effects of spatial policies appear after several years. Spatial plans can possibly indicate these effects earlier. To allow policies to be adapted to unwanted developments, the assessments should be available in the early planning stages of these building projects. The Dutch Minister of VROM has asked the Netherlands Environmental Assessment Agency to investigate the feasibility of a monitoring system based on building plans. As building projects take a long period from conception until realization, a monitoring system for these projects should include all plans for the next ten to fifteen years with an indication of the chance that these plans are realized. The existing databases in the Netherlands provide sufficient information to assess consequences of plans for those objectives that are directly related to the urbanization pattern. However, an improvement of these databases is necessary, amongst other things by coordination of these databases [nl

  15. Observing climate change trends in ocean biogeochemistry: when and where.

    Science.gov (United States)

    Henson, Stephanie A; Beaulieu, Claudie; Lampitt, Richard

    2016-04-01

    Understanding the influence of anthropogenic forcing on the marine biosphere is a high priority. Climate change-driven trends need to be accurately assessed and detected in a timely manner. As part of the effort towards detection of long-term trends, a network of ocean observatories and time series stations provide high quality data for a number of key parameters, such as pH, oxygen concentration or primary production (PP). Here, we use an ensemble of global coupled climate models to assess the temporal and spatial scales over which observations of eight biogeochemically relevant variables must be made to robustly detect a long-term trend. We find that, as a global average, continuous time series are required for between 14 (pH) and 32 (PP) years to distinguish a climate change trend from natural variability. Regional differences are extensive, with low latitudes and the Arctic generally needing shorter time series (ocean surface. Our results present a quantitative framework for assessing the adequacy of current and future ocean observing networks for detection and monitoring of climate change-driven responses in the marine ecosystem. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  16. Reference Data as a Basis for National Spatial Data Infrastructure

    Directory of Open Access Journals (Sweden)

    Tomáš Mildorf

    2012-12-01

    Full Text Available Spatial data are increasingly being used for a range of applications beyond their, traditional uses. Collection of such data and their update constitute a substantial part of the total costs for their maintenance. In order to ensure sustainable development in the area of geographic information systems, efficient data custody and coordination mechanisms for data sharing must be put in place. This paper shows the importance of reference data as a basis for national spatial data infrastructure that serves as a platform for decision making processes in society. There are several European initiatives supporting the wider use of spatial data. An example is the INSPIRE Directive. Its principles and the main world trends in data integration pave the way to successful SDI driven by stakeholders and coordinated by national mapping agencies.

  17. Regional trend analysis of surface ozone observations from monitoring networks in eastern North America, Europe and East Asia

    Science.gov (United States)

    Chang, K. L.; Petropavlovskikh, I. V.; Cooper, O. R.; Schultz, M.; Wang, T.

    2017-12-01

    Surface ozone is a greenhouse gas and pollutant detrimental to human health and crop and ecosystem productivity. The Tropospheric Ozone Assessment Report (TOAR) is designed to provide the research community with an up-to-date observation-based overview of tropospheric ozone's global distribution and trends. The TOAR Surface Ozone Database contains ozone metrics at thousands of monitoring sites around the world, densely clustered across mid-latitude North America, western Europe and East Asia. Calculating regional ozone trends across these locations is challenging due to the uneven spacing of the monitoring sites across urban and rural areas. To meet this challenge we conducted a spatial and temporal trend analysis of several TOAR ozone metrics across these three regions for summertime (April-September) 2000-2014, using the generalized additive mixed model (GAMM). Our analysis indicates that East Asia has the greatest human and plant exposure to ozone pollution among investigating regions, with increasing ozone levels through 2014. The results also show that ozone mixing ratios continue to decline significantly over eastern North America and Europe, however, there is less evidence for decreases of daytime average ozone at urban sites. The present-day spatial coverage of ozone monitors in East Asia (South Korea and Japan) and eastern North America is adequate for estimating regional trends by simply taking the average of the individual trends at each site. However the European network is more sparsely populated across its northern and eastern regions and therefore a simple average of the individual trends at each site does not yield an accurate regional trend. This analysis demonstrates that the GAMM technique can be used to assess the regional representativeness of existing monitoring networks, indicating those networks for which a regional trend can be obtained by simply averaging the trends of all individual sites and those networks that require a more

  18. Collective behavior in the spatial spreading of obesity

    Science.gov (United States)

    Gallos, Lazaros K.; Barttfeld, Pablo; Havlin, Shlomo; Sigman, Mariano; Makse, Hernán A.

    2012-06-01

    Obesity prevalence is increasing in many countries at alarming levels. A difficulty in the conception of policies to reverse these trends is the identification of the drivers behind the obesity epidemics. Here, we implement a spatial spreading analysis to investigate whether obesity shows spatial correlations, revealing the effect of collective and global factors acting above individual choices. We find a regularity in the spatial fluctuations of their prevalence revealed by a pattern of scale-free long-range correlations. The fluctuations are anomalous, deviating in a fundamental way from the weaker correlations found in the underlying population distribution indicating the presence of collective behavior, i.e., individual habits may have negligible influence in shaping the patterns of spreading. Interestingly, we find the same scale-free correlations in economic activities associated with food production. These results motivate future interventions to investigate the causality of this relation providing guidance for the implementation of preventive health policies.

  19. A Simple Spatial Working Memory and Attention Test on Paired Symbols Shows Developmental Deficits in Schizophrenia Patients

    Directory of Open Access Journals (Sweden)

    Wei Song

    2013-01-01

    Full Text Available People with neuropsychiatric disorders such as schizophrenia often display deficits in spatial working memory and attention. Evaluating working memory and attention in schizophrenia patients is usually based on traditional tasks and the interviewer’s judgment. We developed a simple Spatial Working Memory and Attention Test on Paired Symbols (SWAPS. It takes only several minutes to complete, comprising 101 trials for each subject. In this study, we tested 72 schizophrenia patients and 188 healthy volunteers in China. In a healthy control group with ages ranging from 12 to 60, the efficiency score (accuracy divided by reaction time reached a peak in the 20–27 age range and then declined with increasing age. Importantly, schizophrenia patients failed to display this developmental trend in the same age range and adults had significant deficits compared to the control group. Our data suggests that this simple Spatial Working Memory and Attention Test on Paired Symbols can be a useful tool for studies of spatial working memory and attention in neuropsychiatric disorders.

  20. Photography activities for developing students’ spatial orientation and spatial visualization

    Science.gov (United States)

    Hendroanto, Aan; van Galen, Frans; van Eerde, D.; Prahmana, R. C. I.; Setyawan, F.; Istiandaru, A.

    2017-12-01

    Spatial orientation and spatial visualization are the foundation of students’ spatial ability. They assist students’ performance in learning mathematics, especially geometry. Considering its importance, the present study aims to design activities to help young learners developing their spatial orientation and spatial visualization ability. Photography activity was chosen as the context of the activity to guide and support the students. This is a design research study consisting of three phases: 1) preparation and designing 2) teaching experiment, and 3) retrospective analysis. The data is collected by tests and interview and qualitatively analyzed. We developed two photography activities to be tested. In the teaching experiments, 30 students of SD Laboratorium UNESA, Surabaya were involved. The results showed that the activities supported the development of students’ spatial orientation and spatial visualization indicated by students’ learning progresses, answers, and strategies when they solved the problems in the activities.

  1. [Spatial regimes: dynamics of intentional homicides in the city of São Paulo between 2000 and 2008].

    Science.gov (United States)

    Nery, Marcelo Batista; Peres, Maria Fernanda Tourinho; Cardia, Nancy; Vicentin, Diego; Adorno, Sérgio

    2012-12-01

    To identify the existence of spatial and temporal patterns in the occurrence of intentional homicides in the municipality of São Paulo (MSP), Brazil, and to discuss the analytical value of taking such patterns into account when designing studies that address the dynamics and factors associated with the incidence of homicides. A longitudinal ecological study was conducted, having as units of analysis 13 205 census tracts and the 96 census districts that congregate these sectors in São Paulo. All intentional homicides reported in the city between 2000 and 2008 were analyzed. The gross homicide rates per 100 000 population was calculated as well as the global and local Bayesian estimates for each census tract during the study period. To verify the possibility of identifying different patterns of the spatial distribution of homicides, we used BoxMap and Moran's I index. The homicide trends in the city of São Paulo in the last decade were not homogeneous and systematic. Instead, seven patterns of spatial distribution were identified; that is, seven spatial regimes for the occurrence of intentional homicides, considering the homicide rates within each census tract as well as the rates in adjacent tracts. These spatial distribution regimes were not contained within the limits of the census tracts and districts. The results show the importance of analyzing the spatial distribution of social phenomena without restriction of political and administrative boundaries.

  2. Study of the spatial and temporal variability of local ecosystems and glaciers of the Antisana Volcano

    Directory of Open Access Journals (Sweden)

    Mauricio Valladares Borja

    2014-12-01

    Full Text Available (Received: 2014/10/31 - Accepted: 2014/12/15The scientific interest in climate change allowed to uncover evidence demonstrating a general warming trend caused by human activities. Facts such as rising sea levels, extreme weather events and retreat of glaciers, are indicators of the presence of alterations of normal weather patterns. In Ecuador, the Antisana is a stratovolcano of strategic importance affecting the climate of the region, in the functioning of the surrounding ecosystems. It is also a reserve of water for the population of the Metropolitan District of Quito (DMQ. The glaciers of the tropical volcano are also suffering the effects of global warming. Its decline over time is of concern and should be analyzed. The present research work performed a spatial and temporal study based on historical series of aerial photographs taken between 1956 and 2011, through geo-processing capabilities of geographic information systems (GIS. The results show a significant decrease in the glaciers of the Antisana Volcano and significant changes in the surrounding local ecological formations.

  3. Integrative Spatial Data Analytics for Public Health Studies of New York State.

    Science.gov (United States)

    Chen, Xin; Wang, Fusheng

    2016-01-01

    Increased accessibility of health data made available by the government provides unique opportunity for spatial analytics with much higher resolution to discover patterns of diseases, and their correlation with spatial impact indicators. This paper demonstrated our vision of integrative spatial analytics for public health by linking the New York Cancer Mapping Dataset with datasets containing potential spatial impact indicators. We performed spatial based discovery of disease patterns and variations across New York State, and identify potential correlations between diseases and demographic, socio-economic and environmental indicators. Our methods were validated by three correlation studies: the correlation between stomach cancer and Asian race, the correlation between breast cancer and high education population, and the correlation between lung cancer and air toxics. Our work will allow public health researchers, government officials or other practitioners to adequately identify, analyze, and monitor health problems at the community or neighborhood level for New York State.

  4. Time series evaluation of landscape dynamics using annual Landsat imagery and spatial statistical modeling: Evidence from the Phoenix metropolitan region

    Science.gov (United States)

    Fan, Chao; Myint, Soe W.; Rey, Sergio J.; Li, Wenwen

    2017-06-01

    Urbanization is a natural and social process involving simultaneous changes to the Earth's land systems, energy flow, demographics, and the economy. Understanding the spatiotemporal pattern of urbanization is increasingly important for policy formulation, decision making, and natural resource management. A combination of satellite remote sensing and patch-based models has been widely adopted to characterize landscape changes at various spatial and temporal scales. Nevertheless, the validity of this type of framework in identifying long-term changes, especially subtle or gradual land modifications is seriously challenged. In this paper, we integrate annual image time series, continuous spatial indices, and non-parametric trend analysis into a spatiotemporal study of landscape dynamics over the Phoenix metropolitan area from 1991 to 2010. We harness local indicators of spatial dependence and modified Mann-Kendall test to describe the monotonic trends in the quantity and spatial arrangement of two important land use land cover types: vegetation and built-up areas. Results suggest that declines in vegetation and increases in built-up areas are the two prevalent types of changes across the region. Vegetation increases mostly occur at the outskirts where new residential areas are developed from natural desert. A sizable proportion of vegetation declines and built-up increases are seen in the central and southeast part. Extensive land conversion from agricultural fields into urban land use is one important driver of vegetation declines. The xeriscaping practice also contributes to part of vegetation loss and an increasingly heterogeneous landscape. The quantitative framework proposed in this study provides a pathway to effective landscape mapping and change monitoring from a spatial statistical perspective.

  5. Secular trends in menarcheal age in India-evidence from the Indian human development survey.

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Pathak

    Full Text Available Evidence from a number of countries in Europe and North America point towards the secular declining trend in menarcheal age with considerable spatial variations over the past two centuries. Similar trends were reported in several developing countries from Asia, Africa and Latin America. However, data corroborating any secular trend in the menarcheal age of the Indian population remained sparse and inadequately verified.We examined secular trends, regional heterogeneity and association of socioeconomic, anthropometric and contextual factors with menarcheal age among ever-married women (15-49 years in India. Using the pseudo cohort data approach, we fit multiple linear regression models to estimate secular trends in menarcheal age of 91394 ever-married women using the Indian Human Development Survey.The mean age at menarche among Indian women was 13.76 years (95 % CI: 13.75, 13.77 in 2005. It declined by three months from 13.83 years (95% CI: 13.81, 13.85 among women born prior to 1955-1964, to nearly 13.62 years (95% CI: 13.58, 13.67 among women born during late 1985-1989. However, these aggregate national figures mask extensive spatial heterogeneity as mean age at menarche varied from 15.0 years in Himachal Pradesh during 1955-1964 (95% CI: 14.89-15.11 to about 12.1 years in Assam (95% CI: 11.63-12.56 during 1985-1989.The regression analysis established a reduction of nearly one month per decade, suggesting a secular decline in age at menarche among Indian women. Notably, the menarcheal age was significantly associated with the area of residence, geographic region, linguistic groups, educational attainment, wealth status, caste and religious affiliations among Indian women.

  6. Stability analysis and trend study of a balloon tethered in a wind, with experimental comparisons

    Science.gov (United States)

    Redd, L. T.; Bland, S. R.; Bennett, R. M.

    1973-01-01

    A stability analysis and trend study for a balloon tethered in a steady wind are presented. The linearized, stability-derivative type analysis includes balloon aerodynamics, buoyancy, mass (including apparent mass), and static forces resulting from the tether cable. The analysis has been applied to a balloon 7.64 m in length, and the results are compared with those from tow tests of this balloon. This comparison shows that the analysis gives reasonable predictions for the damping, frequencies, modes of motion, and stability boundaries exhibited by the balloon. A trend study for the 7.64-m balloon was made to illustrate how the stability boundaries are affected by changes in individual stability parameters. The trends indicated in this study may also be applicable to many other tethered-balloon systems.

  7. Spatial accessibility to specific sport facilities and corresponding sport practice: the RECORD Study.

    Science.gov (United States)

    Karusisi, Noëlla; Thomas, Frédérique; Méline, Julie; Chaix, Basile

    2013-04-20

    Physical activity is considered as a major component of a healthy lifestyle. However, few studies have examined the relationships between the spatial accessibility to sport facilities and sport practice with a sufficient degree of specificity. The aim of this study was to investigate the associations between the spatial accessibility to specific types of sports facilities and the practice of the corresponding sports after carefully controlling for various individual socio-demographic characteristics and neighborhood socioeconomic variables. Data from the RECORD Study involving 7290 participants recruited in 2007-2008, aged 30-79 years, and residing in the Paris metropolitan area were analyzed. Four categories of sports were studied: team sports, racket sports, swimming and related activities, and fitness. Spatial accessibility to sport facilities was measured with two complementary approaches that both take into account the street network (distance to the nearest facility and count of facilities around the dwelling). Associations between the spatial accessibility to sport facilities and the practice of the corresponding sports were assessed using multilevel logistic regression after adjusting for individual and contextual characteristics. High individual education and high household income were associated with the practice of racket sports, swimming or related activities, and fitness over the previous 7 days. The spatial accessibility to swimming pools was associated with swimming and related sports, even after adjustment for individual/contextual factors. The spatial accessibility to facilities was not related to the practice of other sports. High neighborhood income was associated with the practice of a racket sport and fitness. Accessibility is a multi-dimensional concept that integrates educational, financial, and geographical aspects. Our work supports the evidence that strategies to increase participation in sport activities should improve the spatial and

  8. RADSS: an integration of GIS, spatial statistics, and network service for regional data mining

    Science.gov (United States)

    Hu, Haitang; Bao, Shuming; Lin, Hui; Zhu, Qing

    2005-10-01

    spatial statistics. The tool also includes some fundamental spatial and non-spatial database in regional population and environment, which can be updated by external database via CD or network. Utilizing this data mining and exploratory analytical tool, the users can easily and quickly analyse the huge mount of the interrelated regional data, and better understand the spatial patterns and trends of the regional development, so as to make a credible and scientific decision. Moreover, it can be used as an educational tool for spatial data analysis and environmental studies. In this paper, we also present a case study on Poyang Lake Basin as an application of the tool and spatial data mining in complex environmental studies. At last, several concluding remarks are discussed.

  9. Decreasing child mortality, spatial clustering and decreasing disparity in North-Western Burkina Faso.

    Science.gov (United States)

    Becher, Heiko; Müller, Olaf; Dambach, Peter; Gabrysch, Sabine; Niamba, Louis; Sankoh, Osman; Simboro, Seraphin; Schoeps, Anja; Stieglbauer, Gabriele; Yé, Yazoume; Sié, Ali

    2016-04-01

    Within relatively small areas, there exist high spatial variations of mortality between villages. In rural Burkina Faso, with data from 1993 to 1998, clusters of particularly high child mortality were identified in the population of the Nouna Health and Demographic Surveillance System (HDSS), a member of the INDEPTH Network. In this paper, we report child mortality with respect to temporal trends, spatial clustering and disparity in this HDSS from 1993 to 2012. Poisson regression was used to describe village-specific child mortality rates and time trends in mortality. The spatial scan statistic was used to identify villages or village clusters with higher child mortality. Clustering of mortality in the area is still present, but not as strong as before. The disparity of child mortality between villages has decreased. The decrease occurred in the context of an overall halving of child mortality in the rural area of Nouna HDSS between 1993 and 2012. Extrapolated to the Millennium Development Goals target period 1990-2015, this yields an estimated reduction of 54%, which is not too far off the aim of a two-thirds reduction. © 2016 John Wiley & Sons Ltd.

  10. Trends in stream nitrogen concentrations for forested reference catchments across the USA

    Science.gov (United States)

    A. Argerich; S.L. Johnson; S.D. Sebestyen; C.C. Rhoades; E. Greathouse; J.D. Knoepp; M.B. Adams; G.E. Likens; J.L. Campbell; W.H. McDowell; F.N. Scatena; G.G. Ice

    2013-01-01

    To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among...

  11. Decentralization as a Cause of Spatial Segregation

    Directory of Open Access Journals (Sweden)

    Jasarovic Ema Alihodzic

    2016-01-01

    Full Text Available City represents an incomplete dynamic process prone to the expansion with a causal link between urban expansion and socio-spatial segregation. The socio-spatial distribution in the city is mostly related to the increased social polarization and inequality. There is a clear connection between divided society and divided city: if society is divided, urban space must be divided. It is the question of the relations between the social inequalities on one hand, and spatial segregation on the other. In the last 10 years, Podgorica is the city that shows alarming statistic values when it comes to demographic trends and the influx of the residents from the northern municipalities, which necessarily causes the city sprawl. Past experiences show that city is unevenly expanding, creating new functions and zones expressed by socio-spatial differences. The beginning of this process lies in modernist conception of the city, by which city was mostly developed, while the current functional organization is based on the same concept. With the first urban plans, which carried similarproblems mentioned in previous section, Podgorica was divided into three clearly differentiated zones: Stara Varoš, Nova Varoš and Novi grad, which became a platform for hierarchical divisions within the space, reflecting them in the society.

  12. Long-term trend analysis on total and extreme precipitation over Shasta Dam watershed.

    Science.gov (United States)

    Toride, Kinya; Cawthorne, Dylan L; Ishida, Kei; Kavvas, M Levent; Anderson, Michael L

    2018-06-01

    California's interconnected water system is one of the most advanced water management systems in the world, and understanding of long-term trends in atmospheric and hydrologic behavior has increasingly being seen as vital to its future well-being. Knowledge of such trends is hampered by the lack of long-period observation data and the uncertainty surrounding future projections of atmospheric models. This study examines historical precipitation trends over the Shasta Dam watershed (SDW), which lies upstream of one of the most important components of California's water system, Shasta Dam, using a dynamical downscaling methodology that can produce atmospheric data at fine time-space scales. The Weather Research and Forecasting (WRF) model is employed to reconstruct 159years of long-term hourly precipitation data at 3km spatial resolution over SDW using the 20th Century Reanalysis Version 2c dataset. Trend analysis on this data indicates a significant increase in total precipitation as well as a growing intensity of extreme events such as 1, 6, 12, 24, 48, and 72-hour storms over the period of 1851 to 2010. The turning point of the increasing trend and no significant trend periods is found to be 1940 for annual precipitation and the period of 1950 to 1960 for extreme precipitation using the sequential Mann-Kendall test. Based on these analysis, we find the trends at the regional scale do not necessarily apply to the watershed-scale. The sharp increase in the variability of annual precipitation since 1970s is also detected, which implies an increase in the occurrence of extreme wet and dry conditions. These results inform long-term planning decisions regarding the future of Shasta Dam and California's water system. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Trend Analysis of Pahang River Using Non-Parametric Analysis: Mann Kendalls Trend Test

    International Nuclear Information System (INIS)

    Nur Hishaam Sulaiman; Mohd Khairul Amri Kamarudin; Mohd Khairul Amri Kamarudin; Ahmad Dasuki Mustafa; Muhammad Azizi Amran; Fazureen Azaman; Ismail Zainal Abidin; Norsyuhada Hairoma

    2015-01-01

    Flood is common in Pahang especially during northeast monsoon season from November to February. Three river cross station: Lubuk Paku, Sg. Yap and Temerloh were selected as area of this study. The stream flow and water level data were gathered from DID record. Data set for this study were analysed by using non-parametric analysis, Mann-Kendall Trend Test. The results that obtained from stream flow and water level analysis indicate that there are positively significant trend for Lubuk Paku (0.001) and Sg. Yap (<0.0001) from 1972-2011 with the p-value < 0.05. Temerloh (0.178) data from 1963-2011 recorded no trend for stream flow parameter but negative trend for water level parameter. Hydrological pattern and trend are extremely affected by outside factors such as north east monsoon season that occurred in South China Sea and affected Pahang during November to March. There are other factors such as development and management of the areas which can be considered as factors affected the data and results. Hydrological Pattern is important to indicate the river trend such as stream flow and water level. It can be used as flood mitigation by local authorities. (author)

  14. TREND OF PRECIPITATION VARIATION IN HUBEI PROVINCE SINCE THE 1960S

    Institute of Scientific and Technical Information of China (English)

    CHEN Zheng-hong; QIN Jun

    2003-01-01

    Through linear regression analysis to the trend of annual, seasonal and monthly precipitation of 72 meteorological stations in Hubei Province from 1961 to 1995, it is revealed that: l) annual precipitation was increasing by 61.0mm/10a in the eastern part of Hubei (112°E as a dividing line) and decreasing by 34.9mm/10a in the western part; 2) precipitation in winter and summer (January, February, March, June and July) was increasing in almost whole province which usually with non-uniformity of precipitation distribution from the south to the north. The precipitation in spring, autumn and winter (April, September, November and December) was decreasing in most of the areas which usually with non-uniformity of precipitation distribution from the east to the west. March and December were transition periods between two spatial distribution pattems mentioned above; 3) the eastem part of Hubei has beome one of precipitation increasing centers in China. The results was consistent with the trend that more frequent flood and drought events happened in Hubei Province which are more different in spatial and temporal scales.

  15. Research trends in studies of medical students' characteristics: a scoping review.

    Science.gov (United States)

    Jung, Sung Soo; Park, Kwi Hwa; Roh, HyeRin; Yune, So Jung; Lee, Geon Ho; Chun, Kyunghee

    2017-09-01

    The purpose of this study is to investigate domestic and international research trends in studies of medical students' characteristics by using the scoping review methods. This study adopted the scoping review to assess papers on the characteristics of medical students. The procedure of research was carried out according to the five steps of the scoping review. The full texts of 100 papers are obtained and are read closely, after which suitable 88 papers are extracted by us for this research. The review is mapped by the year of the study, source, location, author, research design, research subject, objective, and key results. The frequency is analyzed by using Microsoft Excel and SPSS. We found 70 papers (79.5%) on a single medical school, 15 (17.0%) on multiple medical schools, and three (3.4%) on mixed schools, including medical and nonmedical schools. Sixty-nine (79.5%) were cross-sectional studies and 18 (20.5%) were longitudinal studies. Eighty-two papers (93.2%) adopted questionnaire surveys. We summarized research trends of studies on medical students in Korea and overseas by topic, and mapped them into physical health, mental health, psychological characteristics, cognitive characteristics, social characteristics, and career. This study provides insights into the future directions of research for the characteristics of medical students.

  16. Research trends in studies of medical students’ characteristics: a scoping review

    Science.gov (United States)

    2017-01-01

    The purpose of this study is to investigate domestic and international research trends in studies of medical students’ characteristics by using the scoping review methods. This study adopted the scoping review to assess papers on the characteristics of medical students. The procedure of research was carried out according to the five steps of the scoping review. The full texts of 100 papers are obtained and are read closely, after which suitable 88 papers are extracted by us for this research. The review is mapped by the year of the study, source, location, author, research design, research subject, objective, and key results. The frequency is analyzed by using Microsoft Excel and SPSS. We found 70 papers (79.5%) on a single medical school, 15 (17.0%) on multiple medical schools, and three (3.4%) on mixed schools, including medical and nonmedical schools. Sixty-nine (79.5%) were cross-sectional studies and 18 (20.5%) were longitudinal studies. Eighty-two papers (93.2%) adopted questionnaire surveys. We summarized research trends of studies on medical students in Korea and overseas by topic, and mapped them into physical health, mental health, psychological characteristics, cognitive characteristics, social characteristics, and career. This study provides insights into the future directions of research for the characteristics of medical students. PMID:28870017

  17. Research trends in studies of medical students’ characteristics: a scoping review

    Directory of Open Access Journals (Sweden)

    Sung Soo Jung

    2017-09-01

    Full Text Available The purpose of this study is to investigate domestic and international research trends in studies of medical students’ characteristics by using the scoping review methods. This study adopted the scoping review to assess papers on the characteristics of medical students. The procedure of research was carried out according to the five steps of the scoping review. The full texts of 100 papers are obtained and are read closely, after which suitable 88 papers are extracted by us for this research. The review is mapped by the year of the study, source, location, author, research design, research subject, objective, and key results. The frequency is analyzed by using Microsoft Excel and SPSS. We found 70 papers (79.5% on a single medical school, 15 (17.0% on multiple medical schools, and three (3.4% on mixed schools, including medical and nonmedical schools. Sixty-nine (79.5% were cross-sectional studies and 18 (20.5% were longitudinal studies. Eighty-two papers (93.2% adopted questionnaire surveys. We summarized research trends of studies on medical students in Korea and overseas by topic, and mapped them into physical health, mental health, psychological characteristics, cognitive characteristics, social characteristics, and career. This study provides insights into the future directions of research for the characteristics of medical students.

  18. Spatial scan statistics to assess sampling strategy of antimicrobial resistance monitoring programme

    DEFF Research Database (Denmark)

    Vieira, Antonio; Houe, Hans; Wegener, Henrik Caspar

    2009-01-01

    Pie collection and analysis of data on antimicrobial resistance in human and animal Populations are important for establishing a baseline of the occurrence of resistance and for determining trends over time. In animals, targeted monitoring with a stratified sampling plan is normally used. However...... sampled by the Danish Integrated Antimicrobial Resistance Monitoring and Research Programme (DANMAP), by identifying spatial Clusters of samples and detecting areas with significantly high or low sampling rates. These analyses were performed for each year and for the total 5-year study period for all...... by an antimicrobial monitoring program....

  19. Quantitative studies with the gamma-camera: correction for spatial and energy distortion

    International Nuclear Information System (INIS)

    Soussaline, F.; Todd-Pokropek, A.E.; Raynaud, C.

    1977-01-01

    The gamma camera sensitivity distribution is an important source of error in quantitative studies. In addition, spatial distortion produces apparent variations in count density which degrades quantitative studies. The flood field image takes into account both effects and is influenced by the pile-up of the tail distribution. It is essential to measure separately each of these parameters. These were investigated using a point source displaced by a special scanning table with two X, Y stepping motors of 10 micron precision. The spatial distribution of the sensitivity, spatial distortion and photopeak in the field of view were measured and compared for different setting-up of the camera and PM gains. For well-tuned cameras, the sensitivity is fairly constant, while the variations appearing in the flood field image are primarily due to spatial distortion, the former more dependent than the latter on the energy window setting. This indicates why conventional flood field uniformity correction must not be applied. A correction technique to improve the results in quantitative studies has been tested using a continuously matched energy window at every point within the field. A method for correcting spatial distortion is also proposed, where, after an adequately sampled measurement of this error, a transformation can be applied to calculate the true position of events. The knowledge of the magnitude of these parameters is essential in the routine use and design of detector systems

  20. Trends in soil erosion and woody shrub encroachment in Ngqushwa district, Eastern Cape Province, South Africa.

    Science.gov (United States)

    Manjoro, Munyaradzi; Kakembo, Vincent; Rowntree, Kate M

    2012-03-01

    Woody shrub encroachment severely impacts on the hydrological and erosion response of rangelands and abandoned cultivated lands. These processes have been widely investigated at various spatial scales, using mostly field experimentation. The present study used remote sensing to investigate spatial and temporal patterns of soil erosion and encroachment by a woody shrub species, Pteronia incana, in a catchment in Ngqushwa district, Eastern Cape Province, South Africa between 1998 and 2008. The extreme categories of soil erosion and shrub encroachment were mapped with higher accuracy than the intermediate ones, particularly where lower spatial resolution data were used. The results showed that soil erosion in the worst category increased simultaneously with dense woody shrub encroachment on the hill slopes. This trend is related to the spatial patterning of woody shrub vegetation that increases bare soil patches--leading to runoff connectivity and concentration of overland flow. The major changes in soil erosion and shrub encroachment analysed during the 10-year period took place in the 5-9° slope category and on the concave slope form. Multi-temporal analyses, based on remote sensing, can extend our understanding of the dynamics of soil erosion and woody shrub encroachment. They may help benchmark the processes and assist in upscaling field studies.

  1. Temporal and spatial trends studied by lichen analysis: atmospheric deposition of trace elements in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Aspiazu, J.; Cervantes, L.; Ramirez, J.; Lopez, J.; Villasenor, P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Ramos, R.; Munoz, R. [Secretaria del Medio Ambiente, Gestion Ambiental del Aire, Mexico City (Mexico)

    2007-07-01

    Ball moss on Tillandsia recurvata (Bromeliaceae), collected in an area previously identified as unpolluted, was transplanted to thirteen bio-monitoring sites in the downtown and metropolitan areas of Mexico City (which cover a surface of 9,560 km{sup 2}) during the periods August 2002 - January 2003 and July 2003 - October 2003. A total of 52 lichens (weighing 300 g) were transplanted to each place. Two were analysed as zero or reference, El Chico National Park, a location 100 Km upwind from the city and the remaining 26 were hung in nylon net bags in order to be able to collect two transplanted tree month, out of every season over a one-year period. The concentrations were measured by the quantitative PIXE method based on an extemal beam facility. The atmospheric deposition for trace elements was inferred by its concentration in lichen samples collected in 2002 from 13 sites in Mexico and compared with data from a similar survey in 2003. The concentration of Cr, Cu, Co, Fe, Mn, Ni, Pb and Zn and other elements was determined for each sample. Maps for each element were drawn after a geostatistical estimate of the metal concentration in the sample was made. Maps were drawn for all elements with the estimated values. Geographical distribution patterns were obtained for the different metals, reflecting the contribution of natural and anthropogenic emission sources. The deposition patterns of V, As, Se, Cd and Pb are substantially influenced by long-range transport from other parts of Mexico City. For Cr, Fe, Co, Ni, and Cu, the deposition patterns are largely determined by contribution from point sources within Mexico and in the metropolitan area. The lichen data for Br and, in part, Se reflect an airborne supply from the environment. Contributions to trace element concentrations in lichen sources other than atmospheric deposition are identified and discussed. The Spatial and temporal variations in the distribution of metal concentration are discussed. (Author)

  2. Temporal and spatial trends studied by lichen analysis: atmospheric deposition of trace elements in Mexico

    International Nuclear Information System (INIS)

    Aspiazu, J.; Cervantes, L.; Ramirez, J.; Lopez, J.; Villasenor, P.; Ramos, R.; Munoz, R.

    2007-01-01

    Ball moss on Tillandsia recurvata (Bromeliaceae), collected in an area previously identified as unpolluted, was transplanted to thirteen bio-monitoring sites in the downtown and metropolitan areas of Mexico City (which cover a surface of 9,560 km 2 ) during the periods August 2002 - January 2003 and July 2003 - October 2003. A total of 52 lichens (weighing 300 g) were transplanted to each place. Two were analysed as zero or reference, El Chico National Park, a location 100 Km upwind from the city and the remaining 26 were hung in nylon net bags in order to be able to collect two transplanted tree month, out of every season over a one-year period. The concentrations were measured by the quantitative PIXE method based on an extemal beam facility. The atmospheric deposition for trace elements was inferred by its concentration in lichen samples collected in 2002 from 13 sites in Mexico and compared with data from a similar survey in 2003. The concentration of Cr, Cu, Co, Fe, Mn, Ni, Pb and Zn and other elements was determined for each sample. Maps for each element were drawn after a geostatistical estimate of the metal concentration in the sample was made. Maps were drawn for all elements with the estimated values. Geographical distribution patterns were obtained for the different metals, reflecting the contribution of natural and anthropogenic emission sources. The deposition patterns of V, As, Se, Cd and Pb are substantially influenced by long-range transport from other parts of Mexico City. For Cr, Fe, Co, Ni, and Cu, the deposition patterns are largely determined by contribution from point sources within Mexico and in the metropolitan area. The lichen data for Br and, in part, Se reflect an airborne supply from the environment. Contributions to trace element concentrations in lichen sources other than atmospheric deposition are identified and discussed. The Spatial and temporal variations in the distribution of metal concentration are discussed. (Author)

  3. SPATIAL CLUSTER AND OUTLIER IDENTIFICATION OF GEOCHEMICAL ASSOCIATION OF ELEMENTS: A CASE STUDY IN JUIRUI COPPER MINING AREA

    Directory of Open Access Journals (Sweden)

    Tien Thanh NGUYEN

    2016-12-01

    Full Text Available Spatial clusters and spatial outliers play an important role in the study of the spatial distribution patterns of geochemical data. They characterize the fundamental properties of mineralization processes, the spatial distribution of mineral deposits, and ore element concentrations in mineral districts. In this study, a new method for the study of spatial distribution patterns of multivariate data is proposed based on a combination of robust Mahalanobis distance and local Moran’s Ii. In order to construct the spatial matrix, the Moran's I spatial correlogram was first used to determine the range. The robust Mahalanobis distances were then computed for an association of elements. Finally, local Moran’s Ii statistics was used to measure the degree of spatial association and discover the spatial distribution patterns of associations of Cu, Au, Mo, Ag, Pb, Zn, As, and Sb elements including spatial clusters and spatial outliers. Spatial patterns were analyzed at six different spatial scales (2km, 4 km, 6 km, 8 km, 10 km and 12 km for both the raw data and Box-Cox transformed data. The results show that identified spatial cluster and spatial outlier areas using local Moran’s Ii and the robust Mahalanobis accord the objective reality and have a good conformity with known deposits in the study area.

  4. Trends in size of tropical deforestation events signal increasing dominance of industrial-scale drivers

    Science.gov (United States)

    Austin, Kemen G.; González-Roglich, Mariano; Schaffer-Smith, Danica; Schwantes, Amanda M.; Swenson, Jennifer J.

    2017-05-01

    Deforestation continues across the tropics at alarming rates, with repercussions for ecosystem processes, carbon storage and long term sustainability. Taking advantage of recent fine-scale measurement of deforestation, this analysis aims to improve our understanding of the scale of deforestation drivers in the tropics. We examined trends in forest clearings of different sizes from 2000-2012 by country, region and development level. As tropical deforestation increased from approximately 6900 kha yr-1 in the first half of the study period, to >7900 kha yr-1 in the second half of the study period, >50% of this increase was attributable to the proliferation of medium and large clearings (>10 ha). This trend was most pronounced in Southeast Asia and in South America. Outside of Brazil >60% of the observed increase in deforestation in South America was due to an upsurge in medium- and large-scale clearings; Brazil had a divergent trend of decreasing deforestation, >90% of which was attributable to a reduction in medium and large clearings. The emerging prominence of large-scale drivers of forest loss in many regions and countries suggests the growing need for policy interventions which target industrial-scale agricultural commodity producers. The experience in Brazil suggests that there are promising policy solutions to mitigate large-scale deforestation, but that these policy initiatives do not adequately address small-scale drivers. By providing up-to-date and spatially explicit information on the scale of deforestation, and the trends in these patterns over time, this study contributes valuable information for monitoring, and designing effective interventions to address deforestation.

  5. Investigating Snow Cover and Hydrometeorological Trends in Contrasting Hydrological Regimes of the Upper Indus Basin

    Directory of Open Access Journals (Sweden)

    Iqra Atif

    2018-04-01

    Full Text Available The Upper Indus basin (UIB is characterized by contrasting hydrometeorological behaviors; therefore, it has become pertinent to understand hydrometeorological trends at the sub-watershed level. Many studies have investigated the snow cover and hydrometeorological modeling at basin level but none have reported the spatial variability of trends and their magnitude at a sub-basin level. This study was conducted to analyze the trends in the contrasting hydrological regimes of the snow and glacier-fed river catchments of the Hunza and Astore sub-basins of the UIB. Mann-Kendall and Sen’s slope methods were used to study the main trends and their magnitude using MODIS snow cover information (2001–2015 and hydrometeorological data. The results showed that in the Hunza basin, the river discharge and temperature were significantly (p ≤ 0.05 decreased with a Sen’s slope value of −2.541 m3·s−1·year−1 and −0.034 °C·year−1, respectively, while precipitation data showed a non-significant (p ≥ 0.05 increasing trend with a Sen’s slope value of 0.023 mm·year−1. In the Astore basin, the river discharge and precipitation are increasing significantly (p ≤ 0.05 with a Sen’s slope value of 1.039 m3·s−1·year−1 and 0.192 mm·year−1, respectively. The snow cover analysis results suggest that the Western Himalayas (the Astore basin had a stable trend with a Sen’s slope of 0.07% year−1 and the Central Karakoram region (the Hunza River basin shows a slightly increasing trend with a Sen’s slope of 0.394% year−1. Based on the results of this study it can be concluded that since both sub-basins are influenced by different climatological systems (monsoon and westerly, the results of those studies that treat the Upper Indus basin as one unit in hydrometeorological modeling should be used with caution. Furthermore, it is suggested that similar studies at the sub-basin level of the UIB will help in a better understanding of the

  6. Study of storm surge trends in typhoon-prone coastal areas based on observations and surge-wave coupled simulations

    Science.gov (United States)

    Feng, Xingru; Li, Mingjie; Yin, Baoshu; Yang, Dezhou; Yang, Hongwei

    2018-06-01

    This is a study of the storm surge trends in some of the typhoon-prone coastal areas of China. An unstructured-grid, storm surge-wave-tide coupled model was established for the coastal areas of Zhejiang, Fujian and Guangdong provinces. The coupled model has a high resolution in coastal areas, and the simulated results compared well with the in situ observations and satellite altimeter data. The typhoon-induced storm surges along the coast of the study areas were simulated based on the established coupled model for the past 20 years (1997-2016). The simulated results were used to analyze the trends of the storm surges in the study area. The extreme storm surge trends along the central coast of Fujian Province reached up to 0.06 m/y, significant at the 90% confidence level. The duration of the storm surges greater than 1.0 and 0.7 m had an increasing trend along the coastal area of northern Fujian Province, significant at confidence levels of 70%-91%. The simulated trends of the extreme storm surges were also validated by observations from two tide gauge stations. Further studies show that the correlation coefficient (RTE) between the duration of the storm surge greater than 1 m and the annual ENSO index can reach as high as 0.62, significant at the 99% confidence level. This occurred in a location where the storm surge trend was not significant. For the areas with significant increasing storm surge trends, RTE was small and not significant. This study identified the storm surge trends for the full complex coastline of the study area. These results are useful both for coastal management by the government and for coastal engineering design.

  7. Study fidelity spatial contours of industrial robots

    Directory of Open Access Journals (Sweden)

    A. V. Ivanova

    2014-01-01

    Full Text Available The purpose of this paper to identify deviations fidelity spatial contours of industrial robots, determine the error pattern detected, and define the ways to solve the problem.The paper presents the research results of fidelity spatial contours done by Fanuc M- 710iC/50 industrial robot when moving along a predetermined path. The proposed method uses a QC20-W ballbar wireless system of Renishaw company, designed to diagnose the state of the measurement and playback linear and angular displacements of the CNC.The solutions to adapt the QC20-W ballbar system to the constructive peculiarities of industrial robots with five or more independently controlled axes are given. The stages of the preparation of diagnostic systems and software robot movements are described.According to study results of errors that arise while playing back the programmed motions of a fixed point of robot capture in three mutually perpendicular planes its practical accuracy has been defined when performing movements in a given region of the working area, thereby allowing us, eventually, to draw a conclusion on the possibility to use a robot in one technological process or another.The study has resulted in emerging the guidelines for the operation of industrial robots with five or more independently controlled axes. Using these guidelines enables us to increase the playback accuracy of the industrial robot to 0.01 mm.

  8. Shielding studies and LMFBR development achievements and future trends

    International Nuclear Information System (INIS)

    Salvatores, M.

    1990-01-01

    Shielding studies in the last decade have been performed in cooperation with several European countries. Shielding has become a mature discipline that takes advantage of improvements in data and methods and supplies the designer with a better set of tools to tackle much stricter requirements. The paper describes achievements to date and the Super Phenix start-up experiments. The present trends to design (a) reduced axial/radial shields, (b) cores that allow internal storage of irradiated sub-assemblies, and (c) cores with specific axial/radial peripheral core zone architectures to improve sodium void reactivity effects require further studies and experimental validation

  9. A thirty year, fine-scale, characterization of area burned in Canadian forests shows evidence of regionally increasing trends in the last decade.

    Science.gov (United States)

    Coops, Nicholas C; Hermosilla, Txomin; Wulder, Michael A; White, Joanne C; Bolton, Douglas K

    2018-01-01

    Fire as a dominant disturbance has profound implications on the terrestrial carbon cycle. We present the first ever multi-decadal, spatially-explicit, 30 meter assessment of fire regimes across the forested ecoregions of Canada at an annual time-step. From 1985 to 2015, 51 Mha burned, impacting over 6.5% of forested ecosystems. Mean annual area burned was 1,651,818 ha and varied markedly (σ = 1,116,119), with 25% of the total area burned occurring in three years: 1989, 1995, and 2015. Boreal forest types contained 98% of the total area burned, with the conifer-dominated Boreal Shield containing one-third of all burned area. While results confirm no significant national trend in burned area for the period of 1985 to 2015, a significant national increasing trend (α = 0.05) of 11% per year was evident for the past decade (2006 to 2015). Regionally, a significant increasing trend in total burned area from 1985 to 2015 was observed in the Montane Cordillera (2.4% increase per year), while the Taiga Plains and Taiga Shield West displayed significant increasing trends from 2006 to 2015 (26.1% and 12.7% increases per year, respectively). The Atlantic Maritime, which had the lowest burned area of all ecozones (0.01% burned per year), was the only ecozone to display a significant negative trend (2.4% decrease per year) from 1985 to 2015. Given the century-long fire return intervals in many of these ecozones, and large annual variability in burned area, short-term trends need to be interpreted with caution. Additional interpretive cautions are related to year used for trend initiation and the nature and extents of spatial regionalizations used for summarizing findings. The results of our analysis provide a baseline for monitoring future national and regional trends in burned area and offer spatially and temporally detailed insights to inform science, policy, and management.

  10. Trend analysis of air temperature and precipitation time series over Greece: 1955-2010

    Science.gov (United States)

    Marougianni, G.; Melas, D.; Kioutsioukis, I.; Feidas, H.; Zanis, P.; Anandranistakis, E.

    2012-04-01

    In this study, a database of air temperature and precipitation time series from the network of Hellenic National Meteorological Service has been developed in the framework of the project GEOCLIMA, co-financed by the European Union and Greek national funds through the Operational Program "Competitiveness and Entrepreneurship" of the Research Funding Program COOPERATION 2009. Initially, a quality test was applied to the raw data and then missing observations have been imputed with a regularized, spatial-temporal expectation - maximization algorithm to complete the climatic record. Next, a quantile - matching algorithm was applied in order to verify the homogeneity of the data. The processed time series were used for the calculation of temporal annual and seasonal trends of air temperature and precipitation. Monthly maximum and minimum surface air temperature and precipitation means at all available stations in Greece were analyzed for temporal trends and spatial variation patterns for the longest common time period of homogenous data (1955 - 2010), applying the Mann-Kendall test. The majority of the examined stations showed a significant increase in the summer maximum and minimum temperatures; this could be possibly physically linked to the Etesian winds, because of the less frequent expansion of the low over the southeastern Mediterranean. Summer minimum temperatures have been increasing at a faster rate than that of summer maximum temperatures, reflecting an asymmetric change of extreme temperature distributions. Total annual precipitation has been significantly decreased at the stations located in western Greece, as well as in the southeast, while the remaining areas exhibit a non-significant negative trend. This reduction is very likely linked to the positive phase of the NAO that resulted in an increase in the frequency and persistence of anticyclones over the Mediterranean.

  11. Longitudinal study of spatial working memory development in young children.

    Science.gov (United States)

    Tsujii, Takeo; Yamamoto, Eriko; Masuda, Sayako; Watanabe, Shigeru

    2009-05-27

    This study longitudinally compared activity in the frontal cortex during a spatial working memory task between 5-year-old and 7-year-old children using near-infrared spectroscopy. Eight children participated in this study twice, once at 5 years and once at 7 years of age. Behavioral analysis showed that older children performed the working memory task more precisely and more rapidly than younger children. Near-infrared spectroscopy analysis showed that right hemisphere dominance was observed in older children, whereas no hemispheric difference was apparent in younger children. Children with strengthened lateralization showed improved performance from 5 to 7 years. We therefore offer the first demonstration of the developmental changes in frontal cortical activation during spatial working memory tasks during the preschool period.

  12. Spatial and temporal variability of fluoride concentrations in groundwater resources of Larestan and Gerash regions in Iran from 2003 to 2010.

    Science.gov (United States)

    Amini, Hassan; Haghighat, Gholam Ali; Yunesian, Masud; Nabizadeh, Ramin; Mahvi, Amir Hossein; Dehghani, Mohammad Hadi; Davani, Rahim; Aminian, Abd-Rasool; Shamsipour, Mansour; Hassanzadeh, Naser; Faramarzi, Hossein; Mesdaghinia, Alireza

    2016-02-01

    There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in groundwater resources of Larestan and Gerash regions in Iran were analyzed from 2003 to 2010 using a geospatial information system and the Mann-Kendall trend test. The mean concentrations of fluoride for the 8-year period in the eight cities and 31 villages were 1.6 and 2.0 mg/l, respectively; the maximum values were 2.4 and 3.8 mg/l, respectively. Spatial, temporal, and spatiotemporal variability of fluoride in overall groundwater resources were relatively constant over the years. However, results of the Mann-Kendall trend test revealed a monotonic trend in the time series of one city and 11 villages for the 8-year period. Specifically, one city and three villages showed positive significant Kendall's Tau values, suggesting an upward trend in fluoride concentrations over the 8-year period. In contrast, seven villages displayed negative significant Kendall's Tau values, arguing for a downward trend in fluoride concentrations over the years. From 2003 to 2010, approximately 52 % of the Larestan and Gerash areas have had fluoride concentrations above the maximum permissible Iranian drinking water standard fluoride level (1.4 mg/l), and about 116,000 people were exposed to such excess amounts. Therefore, our study supports for a close monitoring of fluoride concentrations from health authorities in monthly intervals, especially in villages and cities that showed positive trend in fluoride concentrations. Moreover, we recommend simultaneous implementation of cost-effective protective measures or interventions until a standard fluoride level is achieved.

  13. Spatial distribution of ozone over Indonesia (Study case: Forest fire event 2015)

    Science.gov (United States)

    Muslimah, Sri; Buce Saleh, Muhamad; Hidayat, Rahmat

    2018-05-01

    Tropospheric ozone is known as surface ozone and caused several health impact. The objective of this study was to analysis spatial distribution of tropospheric ozone over Indonesia case study forest fire event in 2015. Monthly observation measured by Ozone Monitoring Instrument (OMI) have been analysed from January – December 2015 to study spatial distribution of tropospheric ozone related to forest fire event 2015. The study discovered high level of tropospheric column ozone (TCO) from October to November 2015. The result shows increasing average of TCO from September to October almost 6 DU. Meanwhile, monthly number of hotspot is higher in September 2015 with total number 257 hotspot which is acquired by Moderate Resolution Imaging Spectrometer (MODIS) Terra version 6.1 with confidence level same or more than 90%. The hotspot distribution compared with spatial TCO distribution and shows interesting time lag with respect to hotspot distribution, one month. Further study for daily comparison of TCO and forest fire event needed. This result suggested that the tropospheric ozone over the Indonesian region increases in 2015 were remarkable and corresponded to forest fire event.

  14. Addressing trend-related changes within cumulative effects studies in water resources planning

    International Nuclear Information System (INIS)

    Canter, L.W.; Chawla, M.K.; Swor, C.T.

    2014-01-01

    Summarized herein are 28 case studies wherein trend-related causative physical, social, or institutional changes were connected to consequential changes in runoff, water quality, and riparian and aquatic ecological features. The reviewed cases were systematically evaluated relative to their identified environmental effects; usage of analytical frameworks, and appropriate models, methods, and technologies; and the attention given to mitigation and/or management of the resultant causative and consequential changes. These changes also represent important considerations in project design and operation, and in cumulative effects studies associated therewith. The cases were grouped into five categories: institutional changes associated with legislation and policies (seven cases); physical changes from land use changes in urbanizing watersheds (eight cases); physical changes from land use changes and development projects in watersheds (four cases); physical, institutional, and social changes from land use and related policy changes in river basins (three cases); and multiple changes within a comprehensive study of land use and policy changes in the Willamette River Basin in Oregon (six cases). A tabulation of 110 models, methods and technologies used in the studies is also presented. General observations from this review were that the features were unique for each case; the consequential changes were logically based on the causative changes; the analytical frameworks provided relevant structures for the studies, and the identified methods and technologies were pertinent for addressing both the causative and consequential changes. One key lesson was that the cases provide useful, “real-world” illustrations of the importance of addressing trend-related changes in cumulative effects studies within water resources planning. Accordingly, they could be used as an “initial tool kit” for addressing trend-related changes

  15. Addressing trend-related changes within cumulative effects studies in water resources planning

    Energy Technology Data Exchange (ETDEWEB)

    Canter, L.W., E-mail: envimptr@aol.com [University of Oklahoma, Norman, Oklahoma and President, Canter Associates, Inc., Horseshoe Bay, TX (United States); Chawla, M.K. [ERDC-CERL, U.S. Army Corps of Engineers, Champaign, IL (United States); Swor, C.T. [Canter Associates, Inc., Frankewing, TN (United States)

    2014-01-15

    Summarized herein are 28 case studies wherein trend-related causative physical, social, or institutional changes were connected to consequential changes in runoff, water quality, and riparian and aquatic ecological features. The reviewed cases were systematically evaluated relative to their identified environmental effects; usage of analytical frameworks, and appropriate models, methods, and technologies; and the attention given to mitigation and/or management of the resultant causative and consequential changes. These changes also represent important considerations in project design and operation, and in cumulative effects studies associated therewith. The cases were grouped into five categories: institutional changes associated with legislation and policies (seven cases); physical changes from land use changes in urbanizing watersheds (eight cases); physical changes from land use changes and development projects in watersheds (four cases); physical, institutional, and social changes from land use and related policy changes in river basins (three cases); and multiple changes within a comprehensive study of land use and policy changes in the Willamette River Basin in Oregon (six cases). A tabulation of 110 models, methods and technologies used in the studies is also presented. General observations from this review were that the features were unique for each case; the consequential changes were logically based on the causative changes; the analytical frameworks provided relevant structures for the studies, and the identified methods and technologies were pertinent for addressing both the causative and consequential changes. One key lesson was that the cases provide useful, “real-world” illustrations of the importance of addressing trend-related changes in cumulative effects studies within water resources planning. Accordingly, they could be used as an “initial tool kit” for addressing trend-related changes.

  16. Spread of porcine circovirus associated disease (PCVAD in Ontario (Canada swine herds: Part I. Exploratory spatial analysis

    Directory of Open Access Journals (Sweden)

    Young Beth

    2010-12-01

    Full Text Available Abstract Background The systemic form of porcine circovirus associated disease (PCVAD, also known as postweaning multisystemic wasting syndrome (PMWS was initially detected in the early 1990s. Starting in 2004, the Canadian swine industry experienced considerable losses due to PCVAD, concurrent with a shift in genotype of porcine circovirus type 2 (PCV2. Objectives of the current study were to explore spatial characteristics of self-reported PCVAD distribution in Ontario between 2004 and 2008, and to investigate the existence and nature of local spread. Results The study included 278 swine herds from a large disease-monitoring project that included porcine reproductive and respiratory syndrome (PRRS virus-positive herds identified by the diagnostic laboratory, and PRRS virus-negative herds directly from the target population. Herds were included if they had growing pigs present on-site and available geographical coordinates for the sampling site. Furthermore, herds were defined as PCVAD-positive if a producer reported an outbreak of circovirus associated disease, or as PCVAD-negative if no outbreak was noted. Spatial trend was investigated using generalized additive models and time to PCVAD outbreak in a herd using Cox's proportional hazard model; spatial and spatio-temporal clustering was explored using K-functions; and location of most likely spatial and spatio-temporal clusters was investigated using scan statistics. Over the study period, the risk of reporting a PCVAD-positive herd tended to be higher in the eastern part of the province after adjustment for herd PRRS status (P = 0.05. This was partly confirmed for spread (Partial P P = 0.06 existence of spatio-temporal clustering of PCVAD and detection of a spatio-temporal cluster (P = 0.04. Conclusions In Ontario, PCVAD has shown a general trend, spreading from east-to-west. We interpret the existence of spatio-temporal clustering as evidence of spatio-temporal aggregation of PCVAD

  17. Mapping and Evaluation of NDVI Trends from Synthetic Time Series Obtained by Blending Landsat and MODIS Data around a Coalfield on the Loess Plateau

    Directory of Open Access Journals (Sweden)

    Kun Wang

    2013-09-01

    Full Text Available The increasingly intensive and extensive coal mining activities on the Loess Plateau pose a threat to the fragile local ecosystems. Quantifying the effects of coal mining activities on environmental conditions is of great interest for restoring and managing the local ecosystems and resources. This paper generates dense NDVI (Normalized Difference Vegetation Index time series between 2000 and 2011 at a spatial resolution of 30 m by blending Landsat and MODIS (Moderate Resolution Imaging Spectroradiometer data using the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM and further evaluates its capability for mapping vegetation trends around a typical coalfield on the Loss Plateau. Synthetic NDVI images were generated using (1 STARFM-generated NIR (near infrared and red band reflectance data (scheme 1 and (2 Landsat and MODIS NDVI images directly as inputs for STARFM (scheme 2. By comparing the synthetic NDVI images with the corresponding Landsat NDVI, we found that scheme 2 consistently generated better results (0.70 < R2 < 0.76 than scheme 1 (0.56 < R2 < 0.70 in this study area. Trend analysis was then performed with the synthetic dense NDVI time series and the annual maximum NDVI (NDVImax time series. The accuracy of these trends was evaluated by comparing to those from the corresponding MODIS time series, and it was concluded that both the trends from synthetic/MODIS NDVI dense time series and synthetic/MODIS NDVImax time series (2000–2011 were highly consistent. Compared to trends from MODIS time series, trends from synthetic time series are better able to capture fine scale vegetation changes. STARFM-generated synthetic NDVI time series could be used to quantify the effects of mining activities on vegetation, but the test areas should be selected with caution, as the trends derived from synthetic and MODIS time series may be significantly different in some areas.

  18. Spatial variability and trends in Younger Dryas equilibrium line altitudes across the European Alps using a hypsometrically based ELA model: results and implications

    Science.gov (United States)

    Keeler, D. G.; Rupper, S.; Schaefer, J. M.; Finkel, R. C.; Maurer, J. M.

    2016-12-01

    Alpine glaciers constitute an important component of terrestrial paleoclimate records due to, among other characteristics, their high sensitivity to climate change, near global extent, and their integration of myriad climate variables into a single, easily detected signal. Because the glacier equilibrium line altitude (ELA) provides a more explicit representation of climate than many other glacier properties, ELA methods allow for more direct comparisons of multiple glaciers within or between regions. Such comparisons allow for more complete investigations of the ultimate causes of mountain glaciation during specific events. Many studies however tend to focus on a limited number of sites, and employ a large variety of different techniques for ELA reconstruction between studies, making wider climate implications more tenuous. Methods of ELA reconstruction that can be rapidly and consistently applied to an arbitrary number of paleo-glaciers would provide a more accurate portrayal of the changes in climate across a given region. Here we present ELA reconstructions from Egesen Stadial moraines across the European Alps using an ELA model accounting for differences in glacier width, glacier shape, bed topography, ice thickness, and glacier length, including several glaciers constrained to the Younger Dryas using surface exposure dating techniques. We compare reconstructed Younger Dryas ELA values to modern ELA values using the same model, or using end of summer snowline estimates where no glacier is currently present. We further provide uncertainty estimates on the ΔELA using bootstrapped Monte Carlo simulations for the various input parameters. Preliminary results compare favorably to previous glacier studies of the European Younger Dryas, but provide greater context from many glaciers across the region as a whole. Such results allow for a more thorough investigation of the spatial variability and trends in climate during the Younger Dryas across the European Alps, and

  19. Spatial and temporal variability of precipitation in Serbia for the period 1961-2010

    Science.gov (United States)

    Milovanović, Boško; Schuster, Phillip; Radovanović, Milan; Vakanjac, Vesna Ristić; Schneider, Christoph

    2017-10-01

    Monthly, seasonal and annual sums of precipitation in Serbia were analysed in this paper for the period 1961-2010. Latitude, longitude and altitude of 421 precipitation stations and terrain features in their close environment (slope and aspect of terrain within a radius of 10 km around the station) were used to develop a regression model on which spatial distribution of precipitation was calculated. The spatial distribution of annual, June (maximum values for almost all of the stations) and February (minimum values for almost all of the stations) precipitation is presented. Annual precipitation amounts ranged from 500 to 600 mm to over 1100 mm. June precipitation ranged from 60 to 140 mm and February precipitation from 30 to 100 mm. The validation results expressed as root mean square error (RMSE) for monthly sums ranged from 3.9 mm in October (7.5% of the average precipitation for this month) to 6.2 mm in April (10.4%). For seasonal sums, RMSE ranged from 10.4 mm during autumn (6.1% of the average precipitation for this season) to 20.5 mm during winter (13.4%). On the annual scale, RMSE was 68 mm (9.5% of the average amount of precipitation). We further analysed precipitation trends using Sen's estimation, while the Mann-Kendall test was used for testing the statistical significance of the trends. For most parts of Serbia, the mean annual precipitation trends fell between -5 and +5 and +5 and +15 mm/decade. June precipitation trends were mainly between -8 and +8 mm/decade. February precipitation trends generally ranged from -3 to +3 mm/decade.

  20. Water vapour trends at several tropospheric levels over South America between 1973 and 2003

    International Nuclear Information System (INIS)

    Morales, L.; Mattar, C.; Da-Silva, L.; Abarca, R.

    2009-01-01

    In this paper water vapour trends were analyzed at several tropospheric levels over South America between 1973 and 2003. It was carried out using in situ values retrieved by 15 radiosonde stations and NCEP NCAR Reanalysis data (NNR). NNR and radiosonde water vapour data were linked to Koeppen-Geiger climatic zones to calculate anomalies, trends, and the non-parametric statistical significance for each mandatory level. A methodology used to process radiosonde data is shown. Water vapour trends in tropical climates presented positive decadal trends. This is statistically significant for the first mandatory levels retrieved by radiosonde. The highest values are presented in average with NNR; the decadal magnitude for climate Af being 0.15 g kg -1 for 1000 and 925 h Pa, and for climate As 0.27 g kg -1 for 925 and 850 h Pa. For non-tropical climates the magnitude trends of specific humidity are affected by the spatial resolution of NNR, which is seen when comparing the results received by the radiosondes. Finally, this paper shows the initial results of water vapour content trends in the last three decades over South America. Strong climatic events and synoptic oscillations were not commented upon.

  1. Comparative study between ultrahigh spatial frequency algorithm and high spatial frequency algorithm in high-resolution CT of the lungs

    International Nuclear Information System (INIS)

    Oh, Yu Whan; Kim, Jung Kyuk; Suh, Won Hyuck

    1994-01-01

    To date, the high spatial frequency algorithm (HSFA) which reduces image smoothing and increases spatial resolution has been used for the evaluation of parenchymal lung diseases in thin-section high-resolution CT. In this study, we compared the ultrahigh spatial frequency algorithm (UHSFA) with the high spatial frequency algorithm in the assessment of thin section images of the lung parenchyma. Three radiologists compared the UHSFA and HSFA on identical CT images in a line-pair resolution phantom, one lung specimen, 2 patients with normal lung and 18 patients with abnormal lung parenchyma. Scanning of a line-pair resolution phantom demonstrated no difference in resolution between two techniques but it showed that outer lines of the line pairs with maximal resolution looked thicker on UHSFA than those on HSFA. Lung parenchymal detail with UHSFA was judged equal or superior to HSFA in 95% of images. Lung parenchymal sharpness was improved with UHSFA in all images. Although UHSFA resulted in an increase in visible noise, observers did not found that image noise interfered with image interpretation. The visual CT attenuation of normal lung parenchyma is minimally increased in images with HSFA. The overall visual preference of the images reconstructed on UHSFA was considered equal to or greater than that of those reconstructed on HSFA in 78% of images. The ultrahigh spatial frequency algorithm improved the overall visual quality of the images in pulmonary parenchymal high-resolution CT

  2. Study of urban spatial utilization on socio-cultural and environment based on sustainability index (study in Denpasar city)

    Science.gov (United States)

    Wiryananda, N. G. A. K.; Hasibuan, H. S.; Madiasworo, T.

    2018-03-01

    The rapid development of tourism and population growth in Denpasar City stimulated the dynamic changes in the spatial utilization. This study aims to analyse the impact of spatial utilization on sociocultural and environment and formulate the sustainable spatial utilization that accommodate both social and environmental aspects. This research uses methods of spatial analysis and sustainability index. The results showed that during the period of 2011 to 2015 there was an increase of settlement and tourism land uses, meanwhile at the same period the paddy field decreased. The impact of spatial utilization on sociocultural leads to unsustainable, that showed by the decreasing of the sociocultural index from 1.038 in 2011 to 1.036 in 2015. The low of sociocultural index was stated by the increasing poverty, the obedience of traditional rules of purity radius of Temple and the height limit of the building. The impact of spatial utilization on environmental leads to unsustainable, with the environmental index of 1.065 in 2011 decreased to 1.056 in 2015. The decline of environmental index is due to reduced green open space and paddy field. The strategy formulation of sustainable spatial utilization is done by integrating traditional rules into spatial planning, plan the vertical building, strengthening implementation of traditional rules, implementation of perennial paddy field, and the establishment of traditional task control unit of spatial control.

  3. Temporal trends in human vulnerability to excessive heat

    Science.gov (United States)

    Sheridan, Scott C.; Allen, Michael J.

    2018-04-01

    Over recent decades, studies have examined various morbidity and mortality outcomes associated with heat exposure. This review explores the collective knowledge of the temporal trends of heat on human health, with regard to the hypothesis that humans are less vulnerable to heat events presently than in the past. Using Web of Science and Scopus, the authors identified all peer-reviewed articles that contained keywords on human impact (e.g. mortality, morbidity) and meteorological component (e.g. heat, heatwave). After sorting, a total of 71 articles, both case studies and epidemiological studies, contained explicit assessments of temporal trends in human vulnerability, and thus were used in this review. Most of the studies utilized mortality data, focused on the developed world, and showed a general decrease in heat sensitivity. Factors such as the implementation of a heat warning system, increased awareness, and improved quality of life were cited as contributing factors that led to the decreased impact of heat. Despite the overall recent decreases in heat vulnerability, spatial variability was shown, and differences with respect to health outcomes were also discussed. Several papers noted increases in heat’s impact on human health, particularly when unprecedented conditions occurred. Further, many populations, from outdoor workers to rural residents, in addition to the populations in much of the developing world, have been significantly underrepresented in research to date, and temporal changes in their vulnerability should be assessed in future studies. Moreover, continued monitoring and improvement of heat intervention is needed; with projected changes in the frequency, duration, and intensity of heat events combined with shifts in demographics, heat will remain a major public health issue moving forward.

  4. Disentangling the Role of the MEC and LEC in the Processing of Spatial and Non-Spatial Information: Contribution of Lesion Studies

    Directory of Open Access Journals (Sweden)

    Etienne Save

    2017-10-01

    Full Text Available It is now widely accepted that the entorhinal cortex (EC plays a pivotal role in the processing of spatial information and episodic memory. The EC is segregated into two sub-regions, the medial EC (MEC and the lateral EC (LEC but a comprehensive understanding of their roles across multiple behavioral contexts remains unclear. Considering that it is still useful to investigate the impact of lesions of EC on behavior, we review the contribution of lesion approach to our knowledge of EC functions. We show that the MEC and LEC play different roles in the processing of spatial and non-spatial information. The MEC is necessary to the use of distal but not proximal landmarks during navigation and is crucial for path integration, in particular integration of linear movements. Consistent with predominant hypothesis, the LEC is important for combining the spatial and non-spatial aspects of the environment. However, object exploration studies suggest that the functional segregation between the MEC and the LEC is not as clearly delineated and is dependent on environmental and behavioral factors. Manipulation of environmental complexity and therefore of cognitive demand shows that the MEC and the LEC are not strictly necessary to the processing of spatial and non-spatial information. In addition we suggest that the involvement of these sub-regions can depend on the kind of behavior, i.e., navigation or exploration, exhibited by the animals. Thus, the MEC and the LEC work in a flexible manner to integrate the “what” and “where” information in episodic memory upstream the hippocampus.

  5. Study of trends in the trucking market in modern conditions

    Directory of Open Access Journals (Sweden)

    P.Popovych

    2016-08-01

    Full Text Available The article analyzes the features of the transport services market in accordance with its segmentation from the position of statistics on the field of automotive freight. The tendencies of development dynamics and road trucking transport market structure, and particularly the impact of transportation logistics market, including foreign trade cargo traffic of road transport, on the basic trends and the impact of logistics infrastructure development for aggregate indicators of development of transport communications, the size and dynamics of development, market compatibility on investment attractiveness. Balance of consumer, wholesale and logistics market in Ukraine, having similar development trends are established. Market logistics of trucking transport services have a steady trend of development in an objective decline in growth. The necessity of modernization policies in the transport sector at the state level as a software-oriented transport sector investment resources of the economy, taking into account that the share of road transport in the transport system of the country demonstrates the dynamic development with a positive trend in demand for transportation of goods.

  6. Trend Analysis of Droughts during Crop Growing Seasons of Nigeria

    Directory of Open Access Journals (Sweden)

    Mohammed Sanusi Shiru

    2018-03-01

    Full Text Available This study assesses the impacts of recent climate changes on drought-affected areas and the occurrence of droughts during different cropping seasons of Nigeria using the standardized precipitation evapotranspiration index (SPEI. The crop growing seasons are considered because the droughts for those periods are more destructive to national agricultural production. The Mann–Kendall test and binary logistic regression were used to quantify the trends in drought-affected areas and the occurrence of crop droughts with different areal extents, respectively. Gauge-based gridded rainfall and temperature data for the period 1961–2010 with spatial resolutions of 0.5° were used. Results showed an increase in the areal extent of droughts during some of the cropping seasons. The occurrences of droughts, particularly moderate droughts with smaller areal extents, were found to increase for all of the seasons. The SPEI values calculated decreased mostly in the regions where rainfall was decreasing. That is, the recent changes in climate were responsible for the increase in the occurrences of droughts with smaller areal extents. These trends in climate indicate that the occurrence of larger areal extent droughts may happen more frequently in Nigeria in the future.

  7. Quantifying Forest Spatial Pattern Trends at Multiple Extents: An Approach to Detect Significant Changes at Different Scales

    Directory of Open Access Journals (Sweden)

    Ludovico Frate

    2014-09-01

    Full Text Available We propose a procedure to detect significant changes in forest spatial patterns and relevant scales. Our approach consists of four sequential steps. First, based on a series of multi-temporal forest maps, a set of geographic windows of increasing extents are extracted. Second, for each extent and date, specific stochastic simulations that replicate real-world spatial pattern characteristics are run. Third, by computing pattern metrics on both simulated and real maps, their empirical distributions and confidence intervals are derived. Finally, multi-temporal scalograms are built for each metric. Based on cover maps (1954, 2011 with a resolution of 10 m we analyze forest pattern changes in a central Apennines (Italy reserve at multiple spatial extents (128, 256 and 512 pixels. We identify three types of multi-temporal scalograms, depending on pattern metric behaviors, describing different dynamics of natural reforestation process. The statistical distribution and variability of pattern metrics at multiple extents offers a new and powerful tool to detect forest variations over time. Similar procedures can (i help to identify significant changes in spatial patterns and provide the bases to relate them to landscape processes; (ii minimize the bias when comparing pattern metrics at a single extent and (iii be extended to other landscapes and scales.

  8. Trends in marketing library services in urban areas: A case study of ...

    African Journals Online (AJOL)

    This article presents the findings of a study that was undertaken in Kampala City, Uganda, in nine libraries belonging to the private sector, government, academic and diplomatic- related institutions. The aim of the study was to establish trends in marketing library services in urban areas with a view to identify marketing ...

  9. Spatiotemporal characteristics of aerosols and their trends over mainland China with the recent Collection 6 MODIS and OMI satellite datasets.

    Science.gov (United States)

    Hu, Kang; Kumar, Kanike Raghavendra; Kang, Na; Boiyo, Richard; Wu, Jinwen

    2018-03-01

    With the rapid development of China's economy and high rate of industrialization, environmental pollution has become a major challenge for the country. The present study is aimed at analyzing spatiotemporal heterogeneities and changes in trends of different aerosol optical properties observed over China. To achieve this, Collection 6 Level 3 data retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS; 2002-2016) and Ozone Monitoring Instrument (OMI; 2005-2016) sensors were used to investigate aerosol optical depth (AOD 550 ), Ångstrӧm exponent (AE 470-660 ), and Absorption Aerosol Index (AAI). The spatial distribution of annual mean AOD 550 was noticed to be high over economically and industrialized regions of the east, south, and northeast of China, while low aerosol loadings were located over rural and less-developed areas of the west and northeast of China. High AE 470-660 (> 1.0) values were characterized by the abundance of fine-mode particles and vice versa, likely attributed to large anthropogenic activities. Similarly, high AOD with corresponding high AE and low AAI was characterized over the urban-industrialized regions of the central, east, and south of China during most of the months, being more pronounced in June and July. On seasonal scale, AOD values were found to be high during spring, followed by the summer and autumn, and low during the winter season. It is also evident that all aerosol parameters showed a single-peak frequency distribution in all seasons over entire China. Further, the annual, monthly, and seasonal spatial trends revealed a decreasing trend in AOD over most regions of China, except in the southwest of China, which showed a positive increasing trend. Significant increasing trends were noted in AAI for all the seasons, particularly during autumn and winter, resulting in a large amount of the absorbing type of aerosols produced from biomass burning and desert dust.

  10. A Study on the Spatial Abilities of Prospective Social Studies Teachers: A Mixed Method Research

    Science.gov (United States)

    Yurt, Eyüp; Tünkler, Vural

    2016-01-01

    This study investigated prospective social studies teachers' spatial abilities. It was conducted with 234 prospective teachers attending Social Studies Teaching departments at Education Faculties of two universities in Central and Southern Anatolia. This study, designed according to the explanatory-sequential design, is a mixed research method,…

  11. Comprehensive Status and Trends of Nitrogen Loads to Estuaries in the Conterminous United States: Pacific Coast Results

    Science.gov (United States)

    We applied regional SPARROW (SPAtially Referenced Regressions On Watershed attributes) models to estimate status and trends of potential nitrogen loads to estuaries of the conterminous United States. The original Regional SPARROW models predict average detrended loads by source ...

  12. Spatial-temporal cluster analysis of mortality from road traffic injuries using geographic information systems in West of Iran during 2009-2014.

    Science.gov (United States)

    Zangeneh, Alireza; Najafi, Farid; Karimi, Saeed; Saeidi, Shahram; Izadi, Neda

    2018-04-01

    Road traffic injuries (RTIs) are considered as one of the most important health problems endangering people's life. The examination of the geographical distribution of RTIs could help policymakers in better planning to reduce RTIs. This study, therefore, aimed to determine the spatial-temporal clustering of mortality from RTIs in West of Iran. Deaths from RTIs, registered in Forensic Medicine Organization of Kermanshah province over a period of six years (2009-2014), were used. Using negative binomial regression, the mortality trend was investigated. In order to investigate the spatial distribution of RTIs, we used ArcGIS. (Version 10.3). The median age of the 3231 people died in RTIs was 37 (IQR = 31) year, 78.4% were male. The 6-year average mortality rate from RTIs was 27.8/100,000 deaths, and the average rate had a declining trend. The dispersion of RTIs showed that most deaths occurred in Kermanshah, Islamabad, Bisotun, and Harsin road axes, respectively. The mean center of all deaths from RTIs occurred in Kermanshah province, the central area of Kermanshah district. The spatial trend of such deaths has moved to the northeast-southwest, and such deaths were geographically centralized. Results of Moran's I with respect to cluster analysis also indicated positive spatial autocorrelations. The results showed that the mortality rate from RTIs, despite the decline in recent years, is still high when compared with other countries. The clustering of accidents raises the concern that road infrastructure in certain locations may also be a factor. Regarding the results related to the temporal analysis, it is suggested that the enforcement of traffic rules be stricter at rush hours. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  13. Stable isotopes and maize consumption in Central Western Argentina: Temporal and Spatial trends

    International Nuclear Information System (INIS)

    Gil, Adolfo F; Neme, Gustavo A; Tykof, Roben H

    2010-01-01

    This work explores the chronological and spatial variability of collagen and apatite δ 13 C and collagen δ 15 N values for human remains, in order to evaluate the incorporation of corn in the diet in central-western Argentina, the pre-Hispanic Southern limit of American agriculture. The study includes 104 samples of archaeological human remains recovered from sites between 32 o and 40 o S and with chronologies spanning the last 6,000 years. The research also presents information on the isotopic ecology of the region. The δ 13 C results show a low correlation with both latitude and time. The individuals who appear to have a significant amount of maize in the diet are from the northemmost sector and date to the last 1,500 years. Despite that tendency, however, there is extensive variability among all individuals, including those from the same time and place. The results weaken the supposed gradual dispersion in space and time of corn, showing instead a high degree of heterogeneity for the importance of maize near the southern limit of its agricultural diffusion [es

  14. Structure and Origins of Trends in Hydrological Measures over the western United States

    Energy Technology Data Exchange (ETDEWEB)

    Das, T; Hidalgo, H G; Dettinger, M D; Cayan, D R; Pierce, D W; Bonfils, C; Barnett, T P; Bala, G; Mirin, A

    2008-08-22

    This study examines, at 1/8 degree spatial resolution, the geographic structure of observed trends in key hydrologically relevant variables across the western United States (U.S.) over the period 1950-1999, and investigates whether these trends are statistically significantly different from trends associated with natural climate variations. A number of variables were analyzed, including late winter and spring temperature, winter-total snowy days as a fraction of winter-total wet days, 1st April Snow Water Equivalent (SWE) as a fraction of October through March precipitation total (P{sub ONDJFM}), and seasonal (January-February-March; JFM) accumulated runoff as a fraction of water year accumulated runoff. The observed changes were compared to natural internal climate variability simulated by an 850-year control run of the CCSM3-FV climate model, statistically downscaled to a 1/8 degree grid using the method of Constructed Analogues. Both observed and downscaled temperature and precipitation data were then used to drive the Variable Infiltration Capacity (VIC) hydrological model to obtain the hydrological variables analyzed in this study. Large trends (magnitudes found less than 5% of the time in the long control run) are common in the observations, and occupy substantial part of the area (37-42%) over the mountainous western U.S. These trends are strongly related to the large scale warming that appears over 89% of the domain. The strongest changes in the hydrologic variables, unlikely to be associated with natural variability alone, have occurred at medium elevations (750 m to 2500 m for JFM runoff fractions and 500 m-3000 m for SWE/PONDJFM) where warming has pushed temperatures from slightly below to slightly above freezing. Further analysis using the data on selected catchments across the simulation domain indicated that hydroclimatic variables must have changed significantly (at 95% confidence level) over at least 45% of the total catchment area to achieve a

  15. Hedonic approaches based on spatial econometrics and spatial statistics: application to evaluation of project benefits

    Science.gov (United States)

    Tsutsumi, Morito; Seya, Hajime

    2009-12-01

    This study discusses the theoretical foundation of the application of spatial hedonic approaches—the hedonic approach employing spatial econometrics or/and spatial statistics—to benefits evaluation. The study highlights the limitations of the spatial econometrics approach since it uses a spatial weight matrix that is not employed by the spatial statistics approach. Further, the study presents empirical analyses by applying the Spatial Autoregressive Error Model (SAEM), which is based on the spatial econometrics approach, and the Spatial Process Model (SPM), which is based on the spatial statistics approach. SPMs are conducted based on both isotropy and anisotropy and applied to different mesh sizes. The empirical analysis reveals that the estimated benefits are quite different, especially between isotropic and anisotropic SPM and between isotropic SPM and SAEM; the estimated benefits are similar for SAEM and anisotropic SPM. The study demonstrates that the mesh size does not affect the estimated amount of benefits. Finally, the study provides a confidence interval for the estimated benefits and raises an issue with regard to benefit evaluation.

  16. Comparison of spatial and temporal trends of methoxylated PBDEs, PBDEs, and hexabromocyclododecane in herring along the Swedish coast

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, L.; Nylund, K. [ITM, Stockholm Univ. (Sweden); Bignert, A. [Swedish Museum of Natural History, Stockholm (Sweden)

    2004-09-15

    Some brominated flame retardants, for example poly brominated diphenyl ethers (PBDEs) have been identified as ubiquitous environmental contaminants. The use of the technical PentaBDE product in the European Union has been drastically reduced in the last years and is banned from 2004, while another brominated flame retardant, hexabromocyclododecane (HBCD), continues to be used. In addition to the commercial BFR products, methoxylated PBDEs (MeO-PBDEs) have been identified in biota in the aquatic environment. The origin of the MeO-PBDEs is under discussion. To our knowledge, neither OH-PBDEs nor MeO-PBDEs are commercially produced, nor have they been reported as impurities in brominated technical products or formed as byproducts in any industrial process. However, MeO-PBDEs has been reported to be natural products formed in the marine environment. As regards MeO-PBDEs detected in Baltic fish several factors points in the direction of a natural origin. On the other hand, certain MeO-PBDEs detected in environmental samples could also be metabolites/environmental transformation products of PBDEs. Knowledge of the spatial and temporal trends of the flame retardants in biota can be very useful in identifying sources of emission to the environment and in evaluating the impacts of voluntary restrictions / bans (PBDEs) and ongoing use (HBCD) on environmental contamination. In addition, this knowledge could provide valuable help in identifying the origin of the MeO-PBDEs. To this end, the Swedish Environmental Monitoring Programme on Contaminants in Biota (SEMPC) has incorporated these 3 substance groups into its monitoring of organic contaminants in herring (Clupea harengus). In this contribution we report on the results of the first 4 years.

  17. Temporal and spatial patterns of micropollutants in urban receiving waters

    Energy Technology Data Exchange (ETDEWEB)

    Musolff, Andreas, E-mail: andreas.musolff@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Leschik, Sebastian, E-mail: sebastian.leschik@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Moeder, Monika, E-mail: monika.moeder@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstr. 15, 04318 Leipzig (Germany); Strauch, Gerhard, E-mail: gerhard.strauch@ufz.d [UFZ - Helmholtz Centre for Environmental Research, Department of Hydrogeology, Permoserstr. 15, 04318 Leipzig (Germany); Reinstorf, Frido, E-mail: frido.reinstorf@hs-magdeburg.d [University of Applied Sciences Magdeburg-Stendal, Department of Water and Waste Management, Breitscheidstr. 2, 39114 Magdeburg (Germany); Schirmer, Mario, E-mail: mario.schirmer@eawag.c [Eawag, The Swiss Federal Institute of Aquatic Science and Technology, Department of Water Resources and Drinking Water, Ueberlandstr. 133, 8600 Duebendorf (Switzerland)

    2009-11-15

    Based on a monitoring program over the course of a year, we characterize the temporal and spatial distribution of selected micropollutants in an urban watershed within the city of Leipzig, Germany. Micropollutants revealed a ubiquitous presence in untreated and treated wastewater, surface water and groundwater. The loads of 4-nonylphenol in the effluents of the municipal wastewater treatment plant followed a seasonal trend, whereas the loads of all other micropollutants were highly variable and not correlated to seasons. In the surface water, load seasonality of caffeine, galaxolide and tonalide resulted from a rapid removal with increased water temperature. The loads of 4-nonylphenol and of caffeine in the colder months increased when rainfall occurred. In the groundwater, complex spatial and temporal patterns were apparent and were related to varying input, retardation and removal processes. As a consequence, an assessment of micropollutants in urban waters should consider different micropollutants' temporal and spatial variability. - Micropollutants in urban receiving waters are characterized by variable temporal and spatial concentration and load patterns that have to be considered in risk assessments.

  18. ANALYSIS OF SPATIAL PATTERN AND INFLUENCING FACTORS OF E-COMMERCE

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2017-09-01

    Full Text Available This paper aims to study the relationship between e-commerce development and geographical characteristics using data of e-commerce, economy, Internet, express delivery and population from 2011 to 2015. Moran’s I model and GWR model are applied to analyze the spatial pattern of E-commerce and its influencing factors. There is a growth trend of e-commerce from west to east, and it is obvious to see that e-commerce development has a space-time clustering, especially around the Yangtze River delta. The comprehensive factors caculated through PCA are described as fundamental social productivity, resident living standard and population sex structure. The first two factors have positive correlation with e-commerce, and the intensity of effect increases yearly. However, the influence of population sex structure on the E-commerce development is not significant. Our results suggest that the clustering of e-commerce has a downward trend and the impact of driving factors on e-commerce is observably distinct from year to year in space.

  19. Multiscale analysis of the spatial variability of heavy metals and organic matter in soils and groundwater across Spain

    Science.gov (United States)

    Luque-Espinar, J. A.; Pardo-Igúzquiza, E.; Grima-Olmedo, J.; Grima-Olmedo, C.

    2018-06-01

    During the last years there has been an increasing interest in assessing health risks caused by exposure to contaminants found in soil, air, and water, like heavy metals or emerging contaminants. This work presents a study on the spatial patterns and interaction effects among relevant heavy metals (Sb, As and Pb) that may occur together in different minerals. Total organic carbon (TOC) have been analyzed too because it is an essential component in the regulatory mechanisms that control the amount of metal in soils. Even more, exposure to these elements is associated with a number of diseases and environmental problems. These metals can have both natural and anthropogenic origins. A key component of any exposure study is a reliable model of the spatial distribution the elements studied. A geostatistical analysis have been performed in order to show that selected metals are auto-correlated and cross-correlated and type and magnitude of such cross-correlation varies depending on the spatial scale under consideration. After identifying general trends, we analyzed the residues left after subtracting the trend from the raw variables. Three scales of variability were identified (compounds or factors) with scales of 5, 35 and 135 km. The first factor (F1) basically identifies anomalies of natural origin but, in some places, of anthropogenics origin as well. The other two are related to geology (F2 and F3) although F3 represents more clearly geochemical background related to large lithological groups. Likewise, mapping of two major structures indicates that significant faults have influence on the distribution of the studied elements. Finally, influence of soil and lithology on groundwater by means of contingency analysis was assessed.

  20. Controlling for unmeasured confounding and spatial misalignment in long?term air pollution and health studies

    OpenAIRE

    Lee, Duncan; Sarran, Christophe

    2015-01-01

    The health impact of long?term exposure to air pollution is now routinely estimated using spatial ecological studies, owing to the recent widespread availability of spatial referenced pollution and disease data. However, this areal unit study design presents a number of statistical challenges, which if ignored have the potential to bias the estimated pollution?health relationship. One such challenge is how to control for the spatial autocorrelation present in the data after accounting for the...

  1. Visuo-Spatial Imagery Impairment in Posterior Cortical Atrophy: A Cognitive and SPECT Study

    Directory of Open Access Journals (Sweden)

    Simona Gardini

    2011-01-01

    Full Text Available This study investigated the cognitive profile and the cerebral perfusion pattern in a highly educated 70 year old gentleman with posterior cortical atrophy (PCA. Visuo-perceptual abilities, spatial memory, spatial representation and navigation, visuo-spatial mental imagery, semantic and episodic-autobiographical memory were assessed. Regional cerebral blood flow (rCBF was imaged with SPECT. Cognitive testing showed visual-perceptual impairment, apperceptive visual and landmark agnosia, topographical disorientation with way-finding deficits, impaired map learning and poor mental image generation. Semantic memory was normal, while episodic-autobiographical memory was impaired. Reduced rCBF was found mainly in the right hemisphere, in the precentral gyrus, posterior cingulate and middle temporal gyri, cuneus and precuneus, in the left superior temporal and lingual gyri and in the parahippocampus bilaterally. Hypoperfusion in occipito-parietal regions was associated with visuo-spatial deficits, whereas deficits in visuo-spatial mental imagery might reflect dysfunction related to hypoperfusion in the parahippocampus and precuneus, structures which are responsible for spatial and imagery processing. Dissociating performance between preserved semantic memory and poor episodic-autobiographical recall is consistent with a pattern of normal perfusion in frontal and anterior temporal regions but abnormal rCBF in the parahippocampi. The present findings indicate that PCA involves visuo-spatial imagery deficits and provide further validation to current neuro-cognitive models of spatial representation and topographical disorientation.

  2. Spatial accessibility to specific sport facilities and corresponding sport practice: the RECORD Study

    OpenAIRE

    Karusisi, No?lla; Thomas, Fr?d?rique; M?line, Julie; Chaix, Basile

    2013-01-01

    International audience; BACKGROUND: Physical activity is considered as a major component of a healthy lifestyle. However, few studies have examined the relationships between the spatial accessibility to sport facilities and sport practice with a sufficient degree of specificity. The aim of this study was to investigate the associations between the spatial accessibility to specific types of sports facilities and the practice of the corresponding sports after carefully controlling for various i...

  3. Temporal trend of the snow-related variables in Sierra Nevada in the last years: An analysis combining Earth Observation and hydrological modelling

    Science.gov (United States)

    Pérez-Luque, Antonio J.; Herrero, Javier; Bonet, Francisco J.; Pérez-Pérez, Ramón

    2016-04-01

    Climate change is causing declines in snow-cover extent and duration in European mountain ranges. This is especially important in Mediterranean mountain ranges where the observed trends towards precipitation and higher temperatures can provoke problems of water scarcity. In this work, we analyzed temporal trends (2000 to 2014) of snow-related variables obtained from satellite and modelling data in Sierra Nevada, a Mediterranean high-mountain range located in Southern Spain, at 37°N. Snow cover indicators (snow-cover duration, snow-cover onset dates and snow-cover melting dates) were obtained by processing images of MOD10A2 MODIS product using an automated workflow. Precipitation data were obtained using WiMMed, a complete and fully distributed hydrological model that is used to map the annual rainfall and snowfall with a resolution of 30x30 m over the whole study area. It uses expert algorithms to interpolate precipitation and temperature at an hourly scale, and simulates partition of precipitation into snowfall with several methods. For each snow-related indicator (snow-covers and snowfall), a trend analysis was applied at the MODIS pixel scale during the study period (2000-2014). We applied Mann-Kendall test and Theil-Sen slope estimation in each of the pixels comprising Sierra Nevada. The trend analysis assesses the intensity, magnitude and degree of statistical significance during the period analysed. The spatial pattern of these trends was explored according to elevation ranges. Finally, we explored the relationship between trends of snow-cover related indicators and precipitation trends. Our results show that snow-cover has undergone significant changes in the last 14 years. 80 % of the pixels covering Sierra Nevada showed a negative trend in the duration of snow-cover. We also observed a delay in the snow-cover onset date (68.03 % pixels showing a positive trend in the snow-cover onset date) and an advance in the melt date (80.72 % of pixels followed a

  4. Experimental study of spatial distribution of Ar glow discharge plasma

    International Nuclear Information System (INIS)

    Guo, X.M.; Zhou, T.D.; Pai, S.T.

    1996-01-01

    The characteristics of the spatial distribution of Ar glow discharge plasma were experimentally investigated. By means of direct comparisons between theory and experiment, the effects of the variation of gap separation, gas pressure, and electrode radius on the spatial distributions of electron density and electric field were studied. Results indicate that the maximum electron density moves toward the cathode as the gap separation or gas pressure increases while variation of electrode radius produces little effect. Predictions from a theoretical model have been experimentally verified. General agreements between theory and experiment were found to be reasonably good except in the cathode region, where discrepancy exists. copyright 1996 American Institute of Physics

  5. Observed trends of soil fauna in the Antarctic Dry Valleys: early signs of shifts predicted under climate change.

    Science.gov (United States)

    Andriuzzi, W S; Adams, B J; Barrett, J E; Virginia, R A; Wall, D H

    2018-02-01

    Long-term observations of ecological communities are necessary for generating and testing predictions of ecosystem responses to climate change. We investigated temporal trends and spatial patterns of soil fauna along similar environmental gradients in three sites of the McMurdo Dry Valleys, Antarctica, spanning two distinct climatic phases: a decadal cooling trend from the early 1990s through the austral summer of February 2001, followed by a shift to the current trend of warming summers and more frequent discrete warming events. After February 2001, we observed a decline in the dominant species (the nematode Scottnema lindsayae) and increased abundance and expanded distribution of less common taxa (rotifers, tardigrades, and other nematode species). Such diverging responses have resulted in slightly greater evenness and spatial homogeneity of taxa. However, total abundance of soil fauna appears to be declining, as positive trends of the less common species so far have not compensated for the declining numbers of the dominant species. Interannual variation in the proportion of juveniles in the dominant species was consistent across sites, whereas trends in abundance varied more. Structural equation modeling supports the hypothesis that the observed biological trends arose from dissimilar responses by dominant and less common species to pulses of water availability resulting from enhanced ice melt. No direct effects of mean summer temperature were found, but there is evidence of indirect effects via its weak but significant positive relationship with soil moisture. Our findings show that combining an understanding of species responses to environmental change with long-term observations in the field can provide a context for validating and refining predictions of ecological trends in the abundance and diversity of soil fauna. © 2018 by the Ecological Society of America.

  6. Agricultural Set-aside Programs and Grassland Birds: Insights from Broad-scale Population Trends

    Directory of Open Access Journals (Sweden)

    S. Riffell

    2008-10-01

    Full Text Available The Conservation Reserve Program (CRP is a voluntary set-aside program in the United States designed to amelioratesoil erosion, control crop overproduction, enhance water quality, and provide wildlife habitat by replacing crops with other forms of land cover. Because CRP includes primarily grass habitats, it has great potential to benefitdeclining North American grassland bird populations. We looked at the change in national and state population trends of grassland birds and related changes to cover-specific CRP variables (previous research grouped all CRP practices. Changes in national trends after the initiation of the CRP were inconclusive, but we observed signficant bird-CRP relations at the state level. Most bird-CRP relations were positive, except for some species associated with habitats that CRP replaced. Practice- and configuration-specific CRP variables were related to grassland bird trends, rather than a generic measure of all CRP types combined. Considering all CRP land as a single, distinct habitat type may obscure actual relations between birds and set-aside characteristics. Understanding and predictingthe effects of set-aside programs (like CRP or agri-environment schemes on grassland birds is complex and difficult. Because available broad-scale datasets are less than adequate, studies should be conducted at a variety of spatial and temporal scales.

  7. Spatial and temporal trends of bat-borne rabies in Chile.

    Science.gov (United States)

    Escobar, L E; Restif, O; Yung, V; Favi, M; Pons, D J; Medina-Vogel, G

    2015-05-01

    In Chile, while dog rabies has decreased markedly over the last 30 years, bat rabies is still reported frequently. In order to shed new light on the spatiotemporal trends of these reports, we analysed active and passive data from years 1985 and 2012, which included 61 076 samples from 289 counties of Chile. We found that from 1994 to 2012, more than 15 000 bat samples were submitted for diagnostics through passive surveillance, 9·5% of which tested positive for rabies. By contrast, the prevalence of infection was only ~0·4% among the nearly 12 000 bat samples submitted through active surveillance. We found that the prevalence of dog rabies dropped steadily over the same period, with just a single confirmed case since 1998. None of the 928 samples from wild animals, other than bats, were positive for rabies. Although there has been only one confirmed case of human rabies in Chile since 1985, and a single confirmed case in a dog since 1998, bats remain a reservoir for rabies viruses. While active surveillance indicates that rabies prevalence is low in bat colonies, the high proportion of positive bats submitted through passive surveillance is a concern. To prevent human rabies, local public health agencies should increase research on the basic ecology of bats and the role of stray dogs and cats as potential rabies amplifiers.

  8. Spatial behavior of prices in the Russian Federation in 2003–2012

    Directory of Open Access Journals (Sweden)

    Anna Vladimirovna Stupnikova

    2014-07-01

    Full Text Available The heterogeneity of economic development and specifics of the spatial position of regions implies that the regional markets in the country are characterized by varying degrees and trends of price dynamics. The multidirectional and disproportionate changes in the prices in the regional markets, in turn, show that integration in the national market is poor. The work presents the results of research into the spatial behavior of prices in the Russian Federation in 2003–2012, carried out mainly using the descriptive analysis of consumer prices based on the identification of the measures of dispersion of price indicators – standard deviation and the range of variation. The analysis of consumer price indices dynamics shows that the year 2008 is a period of greatest price growth, and also proves that the prices for services and foodstuffs are subject to the highest fluctuations. The analysis of the prices for the fixed set of goods and services shows that consumer prices in the Russian Federation subjects during the analyzed period changed unevenly; however, beginning from 2009 there is a positive trend of reducing fluctuations in their growth rates. The assessment of the spatial dynamics of consumer prices in Russia in 2003–2012 reveals the regions that deviate from the general trend of price behavior to the greatest extent. Judging by the results of the assessment, the greatest differences in prices were observed in the subjects of the Far Eastern Federal District (FEFD. Another important fact is as follows: the high volatility of food prices was observed not only in the remote regions, but also in the neighboring subjects of the Far Eastern Federal District; it allows us to assume that the integration of the food market of the border regions of the district at the national level is poor

  9. Directional semivariogram analysis to identify and rank controls on the spatial variability of fracture networks

    Science.gov (United States)

    Hanke, John R.; Fischer, Mark P.; Pollyea, Ryan M.

    2018-03-01

    In this study, the directional semivariogram is deployed to investigate the spatial variability of map-scale fracture network attributes in the Paradox Basin, Utah. The relative variability ratio (R) is introduced as the ratio of integrated anisotropic semivariogram models, and R is shown to be an effective metric for quantifying the magnitude of spatial variability for any two azimuthal directions. R is applied to a GIS-based data set comprising roughly 1200 fractures, in an area which is bounded by a map-scale anticline and a km-scale normal fault. This analysis reveals that proximity to the fault strongly influences the magnitude of spatial variability for both fracture intensity and intersection density within 1-2 km. Additionally, there is significant anisotropy in the spatial variability, which is correlated with trends of the anticline and fault. The direction of minimum spatial correlation is normal to the fault at proximal distances, and gradually rotates and becomes subparallel to the fold axis over the same 1-2 km distance away from the fault. We interpret these changes to reflect varying scales of influence of the fault and the fold on fracture network development: the fault locally influences the magnitude and variability of fracture network attributes, whereas the fold sets the background level and structure of directional variability.

  10. Urban Land Use Planning Trend and Sustainable Challenges in Socio-Economic Development

    Directory of Open Access Journals (Sweden)

    Muhammad Yousif Mangi

    2018-04-01

    Full Text Available Land use planning is a technical approach for developing and managing the land into various public interests to endorse sustainable socio-economic development. This paper focuses on socio-economic problems by improper allocations of urban land uses particularly in vertical development (High rise buildings. Taluka Qasimabad Town was selected as a case study to observe the existing urban land use trends. Spatial and Quantitative data were collected through detailed land use survey and formal interviews. The ArcGIS and SPSS (Statistical Package for Social Science online software were used to analyze spatial and quantitative data. LRM (Linear Regression Model was used for predicting urban land use change particularly in vertical development by the year 2050. In this context, yearly code and land use change variables were applied in LRM to predict land use change since 2007. The results were found that rapid change in land uses occurred in the study area, by which inhabitants are facing problems like privacy, insecurity, property devaluation, and orientation nearby their accommodations. This research can lead to suggest several ways to improve and enhance urban land use planning approaches for betterment of urban communities.

  11. Can data from disparate long-term fish monitoring programs be used to increase our understanding of regional and continental trends in large river assemblages?

    Science.gov (United States)

    Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian S.; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.

    2018-01-01

    Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers. PMID:29364953

  12. Can data from disparate long-term fish monitoring programs be used to increase our understanding of regional and continental trends in large river assemblages?

    Science.gov (United States)

    Counihan, Timothy D.; Waite, Ian R.; Casper, Andrew F.; Ward, David L.; Sauer, Jennifer S.; Irwin, Elise R.; Chapman, Colin G.; Ickes, Brian; Paukert, Craig P.; Kosovich, John J.; Bayer, Jennifer M.

    2018-01-01

    Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers.

  13. Spatial aspects of planning logistical centres: The case of the economic centre Feniks in the Posavje Region

    Directory of Open Access Journals (Sweden)

    Jure Zavrtanik

    2009-01-01

    Full Text Available Spatial planning of logistics centres follows specific spatial and infrastructural requirements, conditioned by desired traffic flux and scope. Spatial and environmental limitations of the usual freight handling sites are forcing logistical activities to search for areas that can ensure undisturbed expansion and practically unlimited traffic flows. The consequence of this trend is suburbanisation coupled with all the spatial and environmental effects. Within this framework, set against the awareness of the uniqueness of any particular site, the article points out the significance of a comprehensive and timely spatial and environmental planning of logistical centres. Therefore clear spatial objectives, transparent analytical starting blocks and adequate planning regulation prove to be the imperative in the spatial planning of logistical centres and formulation of the spatial concept. Simultaneously, and with respect to the complexity of spatial developments, the significance of territorial cohesion is emphasised, which is manifested as territorial identity, territorial quality and territorial efficiency.

  14. Trend patterns in global sea surface temperature

    DEFF Research Database (Denmark)

    Barbosa, S.M.; Andersen, Ole Baltazar

    2009-01-01

    Isolating long-term trend in sea surface temperature (SST) from El Nino southern oscillation (ENSO) variability is fundamental for climate studies. In the present study, trend-empirical orthogonal function (EOF) analysis, a robust space-time method for extracting trend patterns, is applied to iso...

  15. The Spatial Politics of Spatial Representation

    DEFF Research Database (Denmark)

    Olesen, Kristian; Richardson, Tim

    2011-01-01

    spatial planning in Denmark reveals how fuzzy spatial representations and relational spatial concepts are being used to depoliticise strategic spatial planning processes and to camouflage spatial politics. The paper concludes that, while relational geography might play an important role in building......This paper explores the interplay between the spatial politics of new governance landscapes and innovations in the use of spatial representations in planning. The central premise is that planning experiments with new relational approaches become enmeshed in spatial politics. The case of strategic...

  16. Spatial Analysis and Safety Assessment of Social and Economic Development of Small and Medium Cities

    Directory of Open Access Journals (Sweden)

    Elena Anatolyevna Orekhova

    2016-12-01

    Full Text Available The article discusses the spatial patterns of socio-economic development of small and medium-sized cities in the Volgograd region. We know that small and medium-sized cities as spatial socio-economic systems are not only the support frame of settlement, but the main “engine” of innovative impulses for the surrounding periphery. The scientific novelty of the study consists in the effort to implement a spatial approach to the assessment of the economic security of small and medium-sized cities (SCR. The content of the economic security of cities is determined by two system characteristics of the socio-economic system: economic activity (EA and quality of life (QL of the urban population, or SCR = F (EA; QL. For finding spatial patterns in GIS, great interest is in investigating the environment of each city by calculating the local statistical characteristics of geo-variability which allow assessing trends of spatial variation of the six components of security (human security, technosphere safety, environmental safety, etc., local variations in emissions and their values indicators Ki. The successful solution of these problems is possible with the use of tools of exploratory spatial data analysis (ESDA in ARCGIS, and in particular, the Voronoy maps. The spatial approach has allowed to perform an integrated assessment of the economic security and to evaluate safety risks in small and medium-sized cities of the Volgograd region with the security system of indicators.

  17. New insights into survival trend analyses in cancer population-based studies: the SUDCAN methodology.

    Science.gov (United States)

    Uhry, Zoé; Bossard, Nadine; Remontet, Laurent; Iwaz, Jean; Roche, Laurent

    2017-01-01

    The main objective of the SUDCAN study was to compare, for 15 cancer sites, the trends in net survival and excess mortality rates from cancer 5 years after diagnosis between six European Latin countries (Belgium, France, Italy, Portugal, Spain and Switzerland). The data were extracted from the EUROCARE-5 database. The study period ranged from 6 (Portugal, 2000-2005) to 18 years (Switzerland, 1989-2007). Trend analyses were carried out separately for each country and cancer site; the number of cases ranged from 1500 to 104 000 cases. We developed an original flexible excess rate modelling strategy that accounts for the continuous effects of age, year of diagnosis, time since diagnosis and their interactions. Nineteen models were constructed; they differed in the modelling of the effect of the year of diagnosis in terms of linearity, proportionality and interaction with age. The final model was chosen according to the Akaike Information Criterion. The fit was assessed graphically by comparing model estimates versus nonparametric (Pohar-Perme) net survival estimates. Out of the 90 analyses carried out, the effect of the year of diagnosis on the excess mortality rate depended on age in 61 and was nonproportional in 64; it was nonlinear in 27 out of the 75 analyses where this effect was considered. The model fit was overall satisfactory. We analysed successfully 15 cancer sites in six countries. The refined methodology proved necessary for detailed trend analyses. It is hoped that three-dimensional parametric modelling will be used more widely in net survival trend studies as it has major advantages over stratified analyses.

  18. Assessing the Effect of Spatial Proximity on Urban Growth

    Directory of Open Access Journals (Sweden)

    Eduardo Gomes

    2018-04-01

    Full Text Available Land-Use/Cover Change (LUCC reacts to demographic pressures, economic trends, or improved transport networks. Urban growth with implications on LUCC patterns can be measured using a diversity of methods. Our study derives from Tobler’s first law of geography: ‘everything is related to everything else, but near things are more related than distant ones’. We identified and measured the influence of neighbouring distance on urban growth from the edge of existing urban areas. For that, we have developed a method, built using the NetLogo software tool, which we called Land-use chAnge and Neighbouring Distance (LAND. We selected Torres Vedras (Portugal to conduct our case study due to its increasing urban development in the past few years. The periods of analysis were 1995–2010, 1995–2007, and 2007–2010. The results have shown the influence and the effect of strong spatial correlation between the proximity of existing artificial surfaces and the emergence of new ones. The understanding of the patterns of urban growth is helpful to plan forward land developments. This method can be used to write guidelines for decision makers to monitor urban expansion and define spatial planning priorities.

  19. Mapping and spatial-temporal modeling of Bromus tectorum invasion in central Utah

    Science.gov (United States)

    Jin, Zhenyu

    Cheatgrass, or Downy Brome, is an exotic winter annual weed native to the Mediterranean region. Since its introduction to the U.S., it has become a significant weed and aggressive invader of sagebrush, pinion-juniper, and other shrub communities, where it can completely out-compete native grasses and shrubs. In this research, remotely sensed data combined with field collected data are used to investigate the distribution of the cheatgrass in Central Utah, to characterize the trend of the NDVI time-series of cheatgrass, and to construct a spatially explicit population-based model to simulate the spatial-temporal dynamics of the cheatgrass. This research proposes a method for mapping the canopy closure of invasive species using remotely sensed data acquired at different dates. Different invasive species have their own distinguished phenologies and the satellite images in different dates could be used to capture the phenology. The results of cheatgrass abundance prediction have a good fit with the field data for both linear regression and regression tree models, although the regression tree model has better performance than the linear regression model. To characterize the trend of NDVI time-series of cheatgrass, a novel smoothing algorithm named RMMEH is presented in this research to overcome some drawbacks of many other algorithms. By comparing the performance of RMMEH in smoothing a 16-day composite of the MODIS NDVI time-series with that of two other methods, which are the 4253EH, twice and the MVI, we have found that RMMEH not only keeps the original valid NDVI points, but also effectively removes the spurious spikes. The reconstructed NDVI time-series of different land covers are of higher quality and have smoother temporal trend. To simulate the spatial-temporal dynamics of cheatgrass, a spatially explicit population-based model is built applying remotely sensed data. The comparison between the model output and the ground truth of cheatgrass closure demonstrates

  20. Spatial-temporal consistency between gross primary productivity and solar-induced chlorophyll fluorescence of vegetation in China during 2007-2014

    Science.gov (United States)

    Ma, J.; Xiao, X.; Zhang, Y.; Chen, B.; Zhao, B.

    2017-12-01

    Great significance exists in accurately estimating spatial-temporal patterns of gross primary production (GPP) because of its important role in global carbon cycle. Satellite-based light use efficiency (LUE) models are regarded as an efficient tool in simulating spatially time-sires GPP. However, the estimation of the accuracy of GPP simulations from LUE at both spatial and temporal scales is still a challenging work. In this study, we simulated GPP of vegetation in China during 2007-2014 using a LUE model (Vegetation Photosynthesis Model, VPM) based on MODIS (moderate-resolution imaging spectroradiometer) images of 8-day temporal and 500-m spatial resolutions and NCEP (National Center for Environmental Prediction) climate data. Global Ozone Monitoring Instrument 2 (GOME-2) solar-induced chlorophyll fluorescence (SIF) data were used to compare with VPM simulated GPP (GPPVPM) temporally and spatially using linear correlation analysis. Significant positive linear correlations exist between monthly GPPVPM and SIF data over both single year (2010) and multiple years (2007-2014) in China. Annual GPPVPM is significantly positive correlated with SIF (R2>0.43) spatially for all years during 2007-2014 and all seasons in 2010 (R2>0.37). GPP dynamic trends is high spatial-temporal heterogeneous in China during 2007-2014. The results of this study indicate that GPPVPM is temporally and spatially in line with SIF data, and space-borne SIF data have great potential in validating and parameterizing GPP estimation of LUE-based models.

  1. Trends and Variability of North Pacific Polar Lows

    Directory of Open Access Journals (Sweden)

    Fei Chen

    2013-01-01

    Full Text Available The 6-hourly 1948–2010 NCEP 1 reanalyses have been dynamically downscaled for the region of the North Pacific. With a detecting-and-tracking algorithm, the climatology of North Pacific Polar Lows has been constructed. This derived climatology is consistent with the limited observational evidence in terms of frequency and spatial distribution. The climatology exhibits strong year-to-year variability but weak decadal variability and a small positive trend. A canonical correlation analysis describes the conditioning of the formation of Polar Lows by characteristic seasonal mean flow regimes, which favor, or limit, cold air outbreaks and upper air troughs.

  2. Common Ground for Spatial Cognition? A Behavioral and fMRI Study of Sex Differences in Mental Rotation and Spatial Working Memory

    Directory of Open Access Journals (Sweden)

    Sarah L. Levin

    2005-01-01

    Full Text Available Sex differences in spatial cognition are well documented; males typically outperform females on tasks dealing with mental rotation and spatial navigation, while females tend to outperform males on tasks dealing with object location, relational object location memory, or spatial working memory. Here we investigated both behavioral and neural sex differences in sex-specific spatial abilities. In Experiment 1, sixty-six (30 males, 36 females participants completed computerized mental rotation (MR and spatial working memory (SWM tasks. In Experiment 2, twelve (6 males, 6 females participants were given slightly modified versions of the same tasks during functional magnetic resonance imaging (fMRI. In both experiments, males outperformed females on the MR task, but no behavioral sex difference was observed on the SWM task. Males showed more activation in left parahippocampal gyrus, right medial frontal gyrus, inferior parietal lobe, inferior frontal gyrus in the MR task. Females showed activation in the left parahippocampal gyrus only. For the study condition of the spatial working memory task, females showed activation in left inferior frontal gyrus, while males activated left inferior parietal and medial frontal areas. In the test conditions, females showed activation in the right inferior frontal gyrus, left middle temporal gyrus, and left parahippocampal gyrus. Males activated right medial frontal gyrus and inferior parietal lobe. Interestingly, similar regions – parahippocampal gyrus, inferior parietal lobe, and middle temporal gyrus - were found to be active when males solved mental rotation tasks and females solved spatial working memory tasks. Further, performance was modulated by activation in the parahippocampal gyrus and middle temporal gyrus for males and the middle temporal gyrus and inferior frontal gyrus for females. These data extend previous claims for sex differences in sex specific spatial cognitive abilities by demonstrating

  3. Trend analysis

    International Nuclear Information System (INIS)

    Smith, M.; Jones, D.R.

    1991-01-01

    The goal of exploration is to find reserves that will earn an adequate rate of return on the capital invested. Neither exploration nor economics is an exact science. The authors must therefore explore in those trends (plays) that have the highest probability of achieving this goal. Trend analysis is a technique for organizing the available data to make these strategic exploration decisions objectively and is in conformance with their goals and risk attitudes. Trend analysis differs from resource estimation in its purpose. It seeks to determine the probability of economic success for an exploration program, not the ultimate results of the total industry effort. Thus the recent past is assumed to be the best estimate of the exploration probabilities for the near future. This information is combined with economic forecasts. The computer software tools necessary for trend analysis are (1) Information data base - requirements and sources. (2) Data conditioning program - assignment to trends, correction of errors, and conversion into usable form. (3) Statistical processing program - calculation of probability of success and discovery size probability distribution. (4) Analytical processing - Monte Carlo simulation to develop the probability distribution of the economic return/investment ratio for a trend. Limited capital (short-run) effects are analyzed using the Gambler's Ruin concept in the Monte Carlo simulation and by a short-cut method. Multiple trend analysis is concerned with comparing and ranking trends, allocating funds among acceptable trends, and characterizing program risk by using risk profiles. In summary, trend analysis is a reality check for long-range exploration planning

  4. The influence of caffeine on spatial-selective attention: an event-related potential study.

    Science.gov (United States)

    Ruijter, J; de Ruiter, M B; Snel, J; Lorist, M M

    2000-12-01

    Following the indications of previous studies that caffeine might have a specific effect on the processing of spatial information compared with other types of information, the present study investigated the influence of caffeine on an often used spatial-selective attention task. Event-related potentials (ERPs) were recorded from 11 participants under conditions of caffeine (250 mg) and placebo. Spatial-selective attention effects were reflected in the ERPs as more positive going occipital P1 and broadly distributed P2 components, and more negative going occipital-temporal N1 and broadly distributed N2 components. A treatment effect was found as a more positive going frontal P2 component in the caffeine condition, whereas interactions between treatment and attention were observed for P2 and N2 components, but not for P1 and N1 components. This pattern of results suggests that caffeine has no specific influence on spatial-selective attention, but rather, has a more general facilitating effect on perceptual processing, as well as a possible effect on the frontal control mechanisms, i.e. focusing attention and increasing selectivity.

  5. Study of the epicentral trends and depth sections for aftershocks of ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    2001-01-26

    Jan 26, 2001 ... war trend and ENE-WSW Satpura trend as shown in figure 1. The NE-SW ... and terminates in the Gulf of Kutch. A few more lineaments along this ..... mitting us to present this paper in the international seminar at New Delhi.

  6. Hydro-meteorological trends in the Gidabo catchment of the Rift Valley Lakes Basin of Ethiopia

    Science.gov (United States)

    Belihu, Mamuye; Abate, Brook; Tekleab, Sirak; Bewket, Woldeamlak

    2018-04-01

    The global and regional variability and changes of climate and stream flows are likely to have significant influence on water resource availability. The magnitude and impacts of climate variability and change differs spatially and temporally. This study examines the long term hydroclimatic changes, analyses of the hydro-climate variability and detect whether there exist significant trend or not in the Gidabo catchment, rift valley lakes basin of Ethiopia. Precipitation, temperature and stream flow time series data were used in monthly, seasonal and annual time scales. The precipitation and temperature data span is between 1982 and 2014 and that of stream flow is between 1976 and 2006. To detect trends the analysis were done by using Mann Kendal (MK), Sen's graphical method and to detect change point using the Pettit test. The comparison of trend analysis between MK trend test and Sen graphical method results depict mostly similar pattern. The annual rainfall trends exhibited a significant decrease by about 12 mm per year in the upstream, which is largely driven by the significant decrease in the peak season rainfall. The Pettit test revealed that the years 1997 and 2007 were the change points. It is noted that the rise of temperature over a catchment might have decreased the availability of soil moisture which resulted in less runoff. The temperature analyses also revealed that the catchment was getting warmer; particularly in the upstream. The minimum temperature trend showed a significant increase about 0.08°c per annum. There is generally a decreasing trend in stream flow. The monthly stream flow also exhibited a decreasing trend in February, March and September. The decline in annual and seasonal rainfall and the increase in temperature lead to more evaporation and directly affecting the stream flow negatively. This trend compounded with the growth of population and increasing demand for irrigation water exacerbates the competing demand for water resources. It

  7. Using nestling plasma to assess long-term spatial and temporal concentrations of organochlorine compounds in bald eagles within Voyageurs National Park, Minnesota, USA

    Science.gov (United States)

    H. Tyler Pittman; William W. Bowerman; Leland H. Grim; Teryl G. Grubb; William C. Bridges; Michael R. Wierda

    2015-01-01

    The bald eagle (Haliaeetus leucocephalus) population at Voyageurs National Park (VNP) provides an opportunity to assess long-term temporal and spatial trends of persistent environmental contaminants. Nestling bald eagle plasma samples collected from 1997 to 2010 were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides. Trends of total PCBs,...

  8. Characterizing short-range vs. long-range spatial correlations in dislocation distributions

    International Nuclear Information System (INIS)

    Chevy, Juliette; Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent; Bastie, Pierre; Duval, Paul

    2010-01-01

    Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

  9. Characterizing short-range vs. long-range spatial correlations in dislocation distributions

    Energy Technology Data Exchange (ETDEWEB)

    Chevy, Juliette, E-mail: juliette.chevy@gmail.com [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)] [Laboratoire Science et Ingenierie des Materiaux et Procedes, Grenoble INP-CNRS-UJF, BP 75, 38402 St. Martin d' Heres Cedex (France); Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent [Laboratoire de Physique et Mecanique des Materiaux, Universite Paul Verlaine-Metz/CNRS, Ile du Saulcy, 57045 Metz Cedex (France); Bastie, Pierre [Laboratoire de Spectrometrie Physique, BP 87, 38402 St. Martin d' Heres Cedex (France)] [Institut Laue Langevin, BP 156, 38042 Grenoble Cedex 9 (France); Duval, Paul [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)

    2010-03-15

    Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

  10. State Support of Small and Medium Enterprises in Russia: Spatial Issues

    Directory of Open Access Journals (Sweden)

    Vitaliy Victorovich Aleshchenko

    2015-03-01

    Full Text Available The article is prepared by results of the researches executed at the expense of budgetary funds on the Government task of Financial University, 2014. The paper analyses the spatial asymmetry of the development level of small and medium enterprises (SMEs and its support by the state in Russian regions. Using the integrated assessments of the development level and per capita state support for SMEs the author makes grouping of subjects of the Russian Federation by 5 taxa: «very high development», «high development», «moderate development», «low development» and «very low development». The researcher also composes two-dimensional matrices based on above indicators (SME development and its state support for conditions of 2012 and the forecast to 2015 (under the current trend. The study shows that the asymmetry of the development level will persist over time; and maintaining the existing policy of state support for SMEs will only increase differences in the development level between the Russian territories. Moreover, the stability of matrix of the spatial asymmetry of SMEs does not presuppose stable positive changes. This suggests that the existing mechanism of state support for SMEs does not regulate the processes of spatial development

  11. Understanding the Seasonal Greenness Trends and Controls in South Asia Using Satellite Based Observations

    Science.gov (United States)

    Sarmah, S.; Jia, G.; Zhang, A.; Singha, M.

    2017-12-01

    South Asia (SA) is one of the most remarkable regions in changing vegetation greenness along with its major expansion of agricultural activity, especially irrigated farming. However, SA is predicted to be a vulnerable agricultural regions to future climate changes. The influence of monsoon climate on the seasonal trends and anomalies of vegetation greenness are not well understood in the region which can provide valuable information about climate-ecosystem interaction. This study analyzed the spatio-temporal patterns of seasonal vegetation trends and variability using satellite vegetation indices (VI) including AVHRR Normalized Difference Vegetation Index (NDVI) (1982-2013) and MODIS Enhanced Vegetation Index (EVI) (2000-2013) in summer monsoon (SM) (June-Sept) and winter monsoon (WM) (Dec-Apr) seasons among irrigated cropland (IC), rainfed cropland (RC) and natural vegetation (NV). Seasonal VI variations with climatic factors (precipitation and temperature) and LULC changes have been investigated to identify the forcings behind the vegetation trends and variability. We found that major greening occurred in the last three decades due to the increase in IC productivity noticeably in WM, however, recent (2000-2013) greening trends were lower than the previous decades (1982-1999) in both the IC and RC indicating the stresses on them. The browning trends, mainly concentrated in NV areas were prominent during WM and rigorous since 2000, confirmed from the moderate resolution EVI and LULC datasets. Winter time maximal temperature had been increasing tremendously whereas precipitation trend was not significant over SA. Both the climate variability and LULC changes had integrated effects on the vegetation changes in NV areas specifically in hilly regions. However, LULC impact was intensified since 2000, mostly in north east India. This study also revealed a distinct seasonal variation in spatial distribution of correlation between VI's and climate anomalies over SA

  12. Keeping Up With Fashion: Recent Trends in the Subfields of Study of Doctoral Students in Economics

    OpenAIRE

    Sheng Guo; Jungmin Lee

    2011-01-01

    We conduct an analysis of recent trends on the subfields of study that doctoral students in economics choose for their dissertations. By investigating data on the JEL classification codes of dissertations reported by the Journal of Economic Literature from 1991 to 2007, we find that the trends in the subfields of study of doctoral dissertations follow those of articles published at five major general-interest journals (American Economic Review, Quarterly Journal of Economics, Journal of Polit...

  13. Spatially explicit inference for open populations: estimating demographic parameters from camera-trap studies.

    Science.gov (United States)

    Gardner, Beth; Reppucci, Juan; Lucherini, Mauro; Royle, J Andrew

    2010-11-01

    We develop a hierarchical capture-recapture model for demographically open populations when auxiliary spatial information about location of capture is obtained. Such spatial capture-recapture data arise from studies based on camera trapping, DNA sampling, and other situations in which a spatial array of devices records encounters of unique individuals. We integrate an individual-based formulation of a Jolly-Seber type model with recently developed spatially explicit capture-recapture models to estimate density and demographic parameters for survival and recruitment. We adopt a Bayesian framework for inference under this model using the method of data augmentation which is implemented in the software program WinBUGS. The model was motivated by a camera trapping study of Pampas cats Leopardus colocolo from Argentina, which we present as an illustration of the model in this paper. We provide estimates of density and the first quantitative assessment of vital rates for the Pampas cat in the High Andes. The precision of these estimates is poor due likely to the sparse data set. Unlike conventional inference methods which usually rely on asymptotic arguments, Bayesian inferences are valid in arbitrary sample sizes, and thus the method is ideal for the study of rare or endangered species for which small data sets are typical.

  14. Studies of 21st-Century Precipitation Trends Over West Africa

    Science.gov (United States)

    Druyan, Leonard M.

    2010-01-01

    West Africa includes a semi-arid zone between the Sahara Desert and the humid Gulf of Guinea coast, approximately between 10 N and 20 N, which is irrigated by summer monsoon rains. This article refers to the region as the Sahel. Rain-fed agriculture is the primary sustenance for Sahel populations, and severe droughts (in the 1970s and 1980s), therefore, have devastating negative societal impacts. The future frequency of Sahel droughts and the evolution of its hydrological balance are therefore of great interest. The article reviews 10 recent research studies that attempt to discover how climate changes will affect the hydrology of the Sahel throughout the 21st century. All 10 studies rely on atmosphere ocean global climate model (AOGCM) simulations based on a range of greenhouse gas emissions scenarios. Many of the simulations are contained in the Intergovernmental Panel on Climate Change archives for Assessment Reports #3 and #4. Two of the studies use AOGCM data to drive regional climate models. Seven studies make projections for the first half of the 21st century and eight studies make projections for the second half. Some studies make projections of wetter conditions and some predict more frequent droughts, and each describes the atmospheric processes associated with its prediction. Only one study projects more frequent droughts before 2050, and that is only for continent-wide degradation in vegetation cover. The challenge to correctly simulate Sahel rainfall decadal trends is particularly daunting because multiple physical mechanisms compete to drive the trend upwards or downwards. A variety of model deficiencies, regarding the simulation of one or more of these physical processes, taints models climate change projections. Consequently, no consensus emerges regarding the impact of anticipated greenhouse gas forcing on the hydrology of the Sahel in the second half of the 21st century.

  15. The traveling salesrat: insights into the dynamics of efficient spatial navigation in the rodent

    Science.gov (United States)

    Watkins de Jong, Laurel; Gereke, Brian; Martin, Gerard M.; Fellous, Jean-Marc

    2011-10-01

    Rodent spatial navigation requires the dynamic evaluation of multiple sources of information, including visual cues, self-motion signals and reward signals. The nature of the evaluation, its dynamics and the relative weighting of the multiple information streams are largely unknown and have generated many hypotheses in the field of robotics. We use the framework of the traveling salesperson problem (TSP) to study how this evaluation may be achieved. The TSP is a classical artificial intelligence NP-hard problem that requires an agent to visit a fixed set of locations once, minimizing the total distance traveled. We show that after a few trials, rats converge on a short route between rewarded food cups. We propose that this route emerges from a series of local decisions that are derived from weighing information embedded in the context of the task. We study the relative weighting of spatial and reward information and establish that, in the conditions of this experiment, when the contingencies are not in conflict, rats choose the spatial or reward optimal solution. There was a trend toward a preference for space when the contingencies were in conflict. We also show that the spatial decision about which cup to go to next is biased by the orientation of the animal. Reward contingencies are also shown to significantly and dynamically modulate the decision-making process. This paradigm will allow for further neurophysiological studies aimed at understanding the synergistic role of brain areas involved in planning, reward processing and spatial navigation. These insights will in turn suggest new neural-like architectures for the control of mobile autonomous robots.

  16. Statistical analysis of trends in monthly precipitation at the Limbang River Basin, Sarawak (NW Borneo), Malaysia

    Science.gov (United States)

    Krishnan, M. V. Ninu; Prasanna, M. V.; Vijith, H.

    2018-05-01

    Effect of climate change in a region can be characterised by the analysis of rainfall trends. In the present research, monthly rainfall trends at Limbang River Basin (LRB) in Sarawak, Malaysia for a period of 45 years (1970-2015) were characterised through the non-parametric Mann-Kendall and Spearman's Rho tests and relative seasonality index. Statistically processed monthly rainfall of 12 well distributed rain gauging stations in LRB shows almost equal amount of rainfall in all months. Mann-Kendall and Spearman's Rho tests revealed a specific pattern of rainfall trend with a definite boundary marked in the months of January and August with positive trends in all stations. Among the stations, Limbang DID, Long Napir and Ukong showed positive (increasing) trends in all months with a maximum increase of 4.06 mm/year (p = 0.01) in November. All other stations showed varying trends (both increasing and decreasing). Significant (p = 0.05) decreasing trend was noticed in Ulu Medalam and Setuan during September (- 1.67 and - 1.79 mm/year) and October (- 1.59 and - 1.68 mm/year) in Mann-Kendall and Spearman's Rho tests. Spatial pattern of monthly rainfall trends showed two clusters of increasing rainfalls (maximas) in upper and lower part of the river basin separated with a dominant decreasing rainfall corridor. The results indicate a generally increasing trend of rainfall in Sarawak, Borneo.

  17. Investigation of Spatial and Temporal Trends in Water Quality in Daya Bay, South China Sea

    Science.gov (United States)

    Wu, Mei-Lin; Wang, You-Shao; Dong, Jun-De; Sun, Cui-Ci; Wang, Yu-Tu; Sun, Fu-Lin; Cheng, Hao

    2011-01-01

    The objective is to identify the spatial and temporal variability of the hydrochemical quality of the water column in a subtropical coastal system, Daya Bay, China. Water samples were collected in four seasons at 12 monitoring sites. The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on water quality in Daya Bay. In the spatial pattern, two groups have been identified, with the help of multidimensional scaling analysis and cluster analysis. Cluster I consisted of the sites S3, S8, S10 and S11 in the west and north coastal parts of Daya Bay. Cluster I is mainly related to anthropogenic activities such as fish-farming. Cluster II consisted of the rest of the stations in the center, east and south parts of Daya Bay. Cluster II is mainly related to seawater exchange from South China Sea. PMID:21776234

  18. A comparison of methods to estimate vertical land motion trends from GNSS and altimetry at tide gauge stations

    Science.gov (United States)

    Kleinherenbrink, Marcel; Riva, Riccardo; Frederikse, Thomas

    2018-03-01

    Tide gauge (TG) records are affected by vertical land motion (VLM), causing them to observe relative instead of geocentric sea level. VLM can be estimated from global navigation satellite system (GNSS) time series, but only a few TGs are equipped with a GNSS receiver. Hence, (multiple) neighboring GNSS stations can be used to estimate VLM at the TG. This study compares eight approaches to estimate VLM trends at 570 TG stations using GNSS by taking into account all GNSS trends with an uncertainty smaller than 1 mm yr-1 within 50 km. The range between the methods is comparable with the formal uncertainties of the GNSS trends. Taking the median of the surrounding GNSS trends shows the best agreement with differenced altimetry-tide gauge (ALT-TG) trends. An attempt is also made to improve VLM trends from ALT-TG time series. Only using highly correlated along-track altimetry and TG time series reduces the SD of ALT-TG time series by up to 10 %. As a result, there are spatially coherent changes in the trends, but the reduction in the root mean square (RMS) of differences between ALT-TG and GNSS trends is insignificant. However, setting correlation thresholds also acts like a filter to remove problematic TG time series. This results in sets of ALT-TG VLM trends at 344-663 TG locations, depending on the correlation threshold. Compared to other studies, we decrease the RMS of differences between GNSS and ALT-TG trends (from 1.47 to 1.22 mm yr-1), while we increase the number of locations (from 109 to 155), Depending on the methods the mean of differences between ALT-TG and GNSS trends vary between 0.1 and 0.2 mm yr-1. We reduce the mean of the differences by taking into account the effect of elastic deformation due to present-day mass redistribution. At varying ALT-TG correlation thresholds, we provide new sets of trends for 759 to 939 different TG stations. If both GNSS and ALT-TG trend estimates are available, we recommend using the GNSS trend estimates because residual

  19. Spatial and temporal stability of temperature in the first-level basins of China during 1951-2013

    Science.gov (United States)

    Cheng, Yuting; Li, Peng; Xu, Guoce; Li, Zhanbin; Cheng, Shengdong; Wang, Bin; Zhao, Binhua

    2018-05-01

    In recent years, global warming has attracted great attention around the world. Temperature change is not only involved in global climate change but also closely linked to economic development, the ecological environment, and agricultural production. In this study, based on temperature data recorded by 756 meteorological stations in China during 1951-2013, the spatial and temporal stability characteristics of annual temperature in China and its first-level basins were investigated using the rank correlation coefficient method, the relative difference method, rescaled range (R/S) analysis, and wavelet transforms. The results showed that during 1951-2013, the spatial variation of annual temperature belonged to moderate variability in the national level. Among the first-level basins, the largest variation coefficient was 114% in the Songhuajiang basin and the smallest variation coefficient was 10% in the Huaihe basin. During 1951-2013, the spatial distribution pattern of annual temperature presented extremely strong spatial and temporal stability characteristics in the national level. The variation range of Spearman's rank correlation coefficient was 0.97-0.99, and the spatial distribution pattern of annual temperature showed an increasing trend. In the national level, the Liaohe basin, the rivers in the southwestern region, the Haihe basin, the Yellow River basin, the Yangtze River basin, the Huaihe basin, the rivers in the southeastern region, and the Pearl River basin all had representative meteorological stations for annual temperature. In the Songhuajiang basin and the rivers in the northwestern region, there was no representative meteorological station. R/S analysis, the Mann-Kendall test, and the Morlet wavelet analysis of annual temperature showed that the best representative meteorological station could reflect the variation trend and the main periodic changes of annual temperature in the region. Therefore, strong temporal stability characteristics exist for

  20. Spatial characterization of long-term hydrological change in the Arkavathy watershed adjacent to Bangalore, India

    Science.gov (United States)

    Penny, Gopal; Srinivasan, Veena; Dronova, Iryna; Lele, Sharachchandra; Thompson, Sally

    2018-01-01

    The complexity and heterogeneity of human water use over large spatial areas and decadal timescales can impede the understanding of hydrological change, particularly in regions with sparse monitoring of the water cycle. In the Arkavathy watershed in southern India, surface water inflows to major reservoirs decreased over a 40-year period during which urbanization, groundwater depletion, modification of the river network, and changes in agricultural practices also occurred. These multiple, interacting drivers combined with limited hydrological monitoring make attribution of the causes of diminishing water resources in the watershed challenging and impede effective policy responses. To mitigate these challenges, we developed a novel, spatially distributed dataset to understand hydrological change by characterizing the residual trends in surface water extent that remain after controlling for precipitation variations and comparing the trends with historical land use maps to assess human drivers of change. Using an automated classification approach with subpixel unmixing, we classified water extent in nearly 1700 man-made lakes, or tanks, in Landsat images from 1973 to 2010. The classification results compared well with a reference dataset of water extent of tanks (R2 = 0.95). We modeled the water extent of 42 clusters of tanks in a multiple regression on simple hydrological covariates (including precipitation) and time. Inter-annual variability in precipitation accounted for 63 % of the predicted variability in water extent. However, precipitation did not exhibit statistically significant trends in any part of the watershed. After controlling for precipitation variability, we found statistically significant temporal trends in water extent, both positive and negative, in 13 of the clusters. Based on a water balance argument, we inferred that these trends likely reflect a non-stationary relationship between precipitation and watershed runoff. Independently of

  1. Evaluation and adjustment of altimeter measurement and numerical hindcast in wave height trend estimation in China's coastal seas

    Science.gov (United States)

    Li, Shuiqing; Guan, Shoude; Hou, Yijun; Liu, Yahao; Bi, Fan

    2018-05-01

    A long-term trend of significant wave height (SWH) in China's coastal seas was examined based on three datasets derived from satellite measurements and numerical hindcasts. One set of altimeter data were obtained from the GlobWave, while the other two datasets of numerical hindcasts were obtained from the third-generation wind wave model, WAVEWATCH III, forced by wind fields from the Cross-Calibrated Multi-Platform (CCMP) and NCEP's Climate Forecast System Reanalysis (CFSR). The mean and extreme wave trends were estimated for the period 1992-2010 with respect to the annual mean and the 99th-percentile values of SWH, respectively. The altimeter wave trend estimates feature considerable uncertainties owing to the sparse sampling rate. Furthermore, the extreme wave trend tends to be overestimated because of the increasing sampling rate over time. Numerical wave trends strongly depend on the quality of the wind fields, as the CCMP waves significantly overestimate the wave trend, whereas the CFSR waves tend to underestimate the trend. Corresponding adjustments were applied which effectively improved the trend estimates from the altimeter and numerical data. The adjusted results show generally increasing mean wave trends, while the extreme wave trends are more spatially-varied, from decreasing trends prevailing in the South China Sea to significant increasing trends mainly in the East China Sea.

  2. Trends of particulate matter in four cities in India

    Science.gov (United States)

    Gupta, Indrani; Kumar, Rakesh

    Particulate matter (PM) in all the four Metropolitan cities in India are higher than the prescribed standards of Central Pollution Control Board, India as well as WHO guidelines. Over last 10 years various changes in fuel quality, vehicle technologies, industrial fuel mix and domestic fuel mix have taken place resulting in changes in air quality in these cities. A set of time series analysis methods viz. t-test adjusted for seasonality, Seasonal Kendall test and Intervention analysis have been applied to identify and estimate the trend in PM 10 and total suspended particles (TSP) levels monitored for about 10 years at three monitoring sites at each of the four cities in India. These tests have indicated that overall PM 10 levels in all four metro cities have been decreasing or stationary. The distinct trends for the monthly averages of PM 10 concentrations at Parel, Kalbadevi in Mumbai and Thiruvattiyar in Chennai for the period 1993-2003 were declining by 10%, 6% and 5% per annum, respectively. This is ascribed to a shift in the magnitude and spatial distribution of emissions in the city. However, the monthly averages of TSP do not have a clear trend over the period 1991-2003.

  3. Quantifying spatial and temporal patterns of flow intermittency using spatially contiguous runoff data

    Science.gov (United States)

    Yu (于松延), Songyan; Bond, Nick R.; Bunn, Stuart E.; Xu, Zongxue; Kennard, Mark J.

    2018-04-01

    temporal extent of flow intermittency varied dramatically inter-annually from 1900 to 2016, with the proportion of intermittent (weakly and strongly intermittent) streams ranging in length from 3% to nearly 100% of the river network, but there was no evidence of an increasing trend towards flow intermittency over this period. Our approach to generating spatially explicit and catchment-wide estimates of streamflow intermittency can facilitate improved ecological understanding and management of intermittent streams in Australia and around the world.

  4. Online Marketing Trends

    OpenAIRE

    Horecká, Ivana

    2015-01-01

    This thesis deals with online marketing trends. Its main goal is to define the latest online marketing trends, create a website with the free online marketing trends, and analyse their effectiveness. The theoretical part brings a thorough description of the latest online marketing trends. Moreover, it provides an insight into the latest trends in the website development. The chosen online marketing trends defined in the theoretical part are subsequently applied on a newly created website. All...

  5. Analysis of The Planning Education in the Light of the Contemporary Trends in Planning

    Science.gov (United States)

    Husar, Milan; Ceren Varis, Sila; Ondrejicka, Vladimir

    2017-12-01

    This paper examines the way the planning education is taught and examines the recent trends in the curricula of planning education institutions. The introduction of changing economic systems and planning in the field of education is discussed against these changes. Additionally, the evolution in the planner’s role and how it affects the planning education is discussed. The paper is addressing trends and challenges the countries and their planning changes are facing in 21st century. The trends such as increasing globalization, fuzziness of spatial structures and their borders, complexity and uncertainty and the growing interconnectedness of the world are discussed. Another aim is to prepare a common ground, a platform at the university level for scientific cooperation in the field of planning. This study aims at examining the situation of planning in the contemporary world. The identified challenges include the need for more flexibility in planning and planning education, the emergence of innovations and creativity in planners and planning projects, the necessity of promoting soft skills while keeping the existing technical nature of planning and lastly, the need for more interdisciplinary work. The final part of the paper is discussing the future planning education and recommendations on how the schools of planning should reflect these changes.

  6. Analysis of the spatial distribution of infant mortality by cause of death in Austria in 1984 to 2006

    Directory of Open Access Journals (Sweden)

    Heinzl Harald

    2008-05-01

    Full Text Available Abstract Background In Austria, over the last 20 years infant mortality declined from 11.2 per 1,000 life births (1985 to 4.7 per 1,000 in1997 but remained rather constant since then. In addition to this time trend we already reported a non-random spatial distribution of infant mortality rates in a recent study covering the time period 1984 to 2002. This present study includes four additional years and now covers about 1.9 million individual birth certificates. It aimes to elucidate the observed non-random spatial distribution in more detail. We split up infant mortality into six groups according to the underlying cause of death. The underlying spatial distribution of standardized mortality ratios (SMR is estimated by univariate models as well as by two models incorporating all six groups simultaneously. Results We observe strong correlations between the individual spatial patterns of SMR's except for "Sudden Infant Death Syndrome" and to some extent for "Peripartal Problems". The spatial distribution of SMR's is non-random with an area of decreased risk in the South-East of Austria. The group "Sudden Infant Death Syndrome" clearly and the group "Peripartal Problems" slightly show deviations from the common pattern. When comparing univariate and multivariate SMR estimates we observe that the resulting spatial distributions are very similar. Conclusion We observe different non-random spatial distributions of infant mortality rates when grouped by cause of death. The models applied were based on individual data thereby avoiding ecological regression bias. The estimated spatial distributions do not substantially depend on the employed estimation method. The observed non-random spatial patterns of Austrian infant mortality remain to appear ambiguous.

  7. Eigenvector Spatial Filtering Regression Modeling of Ground PM2.5 Concentrations Using Remotely Sensed Data

    Directory of Open Access Journals (Sweden)

    Jingyi Zhang

    2018-06-01

    Full Text Available This paper proposes a regression model using the Eigenvector Spatial Filtering (ESF method to estimate ground PM2.5 concentrations. Covariates are derived from remotely sensed data including aerosol optical depth, normal differential vegetation index, surface temperature, air pressure, relative humidity, height of planetary boundary layer and digital elevation model. In addition, cultural variables such as factory densities and road densities are also used in the model. With the Yangtze River Delta region as the study area, we constructed ESF-based Regression (ESFR models at different time scales, using data for the period between December 2015 and November 2016. We found that the ESFR models effectively filtered spatial autocorrelation in the OLS residuals and resulted in increases in the goodness-of-fit metrics as well as reductions in residual standard errors and cross-validation errors, compared to the classic OLS models. The annual ESFR model explained 70% of the variability in PM2.5 concentrations, 16.7% more than the non-spatial OLS model. With the ESFR models, we performed detail analyses on the spatial and temporal distributions of PM2.5 concentrations in the study area. The model predictions are lower than ground observations but match the general trend. The experiment shows that ESFR provides a promising approach to PM2.5 analysis and prediction.

  8. Eigenvector Spatial Filtering Regression Modeling of Ground PM2.5 Concentrations Using Remotely Sensed Data.

    Science.gov (United States)

    Zhang, Jingyi; Li, Bin; Chen, Yumin; Chen, Meijie; Fang, Tao; Liu, Yongfeng

    2018-06-11

    This paper proposes a regression model using the Eigenvector Spatial Filtering (ESF) method to estimate ground PM 2.5 concentrations. Covariates are derived from remotely sensed data including aerosol optical depth, normal differential vegetation index, surface temperature, air pressure, relative humidity, height of planetary boundary layer and digital elevation model. In addition, cultural variables such as factory densities and road densities are also used in the model. With the Yangtze River Delta region as the study area, we constructed ESF-based Regression (ESFR) models at different time scales, using data for the period between December 2015 and November 2016. We found that the ESFR models effectively filtered spatial autocorrelation in the OLS residuals and resulted in increases in the goodness-of-fit metrics as well as reductions in residual standard errors and cross-validation errors, compared to the classic OLS models. The annual ESFR model explained 70% of the variability in PM 2.5 concentrations, 16.7% more than the non-spatial OLS model. With the ESFR models, we performed detail analyses on the spatial and temporal distributions of PM 2.5 concentrations in the study area. The model predictions are lower than ground observations but match the general trend. The experiment shows that ESFR provides a promising approach to PM 2.5 analysis and prediction.

  9. Change of spatial information under rescaling: A case study using multi-resolution image series

    Science.gov (United States)

    Chen, Weirong; Henebry, Geoffrey M.

    portrayed by pixels are equally weighted regardless of the shape and extent of the underlying scene objects, the rescaled image retains more of the original spatial information than would occur through direct observation at a coarser sensor spatial resolution. In contrast, for the observed images, due to the effect of the modulation transfer function (MTF) of the imaging system, high frequency features like edges are blurred or lost as the pixel size increases, resulting in greater variation in spatial structure. Successive applications of a low-pass spatial convolution filter are shown to mimic a MTF. Accordingly, it is recommended that such a procedure be applied prior to rescaling by simple block averaging, if insufficient image metadata exist to replicate the net MTF of the imaging system, as might be expected in land cover change analysis studies using historical imagery.

  10. Villes et structures spatiales élémentaires du KwaZulu-Natal

    Directory of Open Access Journals (Sweden)

    Fabrice Folio

    2004-12-01

    Full Text Available However significant the legacy of former segregational policies in the spatial organisation of South African cities, it is important to include other basic spatial structures that have often been minimised. That is the aim of this paper. The towns in KwaZulu-Natal province provide a strong illustration of this point. The urban entities in the province can be differentiated by several criteria – either historical or contemporary – that are not always related to apartheid policy. The towns are underpinned by basic structures that organise the province. These structures are determined not only by racial discrimination, but also by economics. Recent developments seem to reinforce this trend.

  11. Spatiotemporal trend analysis of metal concentrations in sediments of a residential California stream with toxicity and regulatory implications.

    Science.gov (United States)

    Hall, Lenwood W; Anderson, Ronald D; Killen, William D

    2017-06-07

    The objective of this study was to determine if concentrations of arsenic, cadmium, chromium, copper, lead, nickel and zinc measured in the sediments of a residential stream in California (Pleasant Grove Creek) have changed temporally or spatially from 2006 to 2016. Threshold Effect Levels (TELs), conservative ecological effects benchmarks, and exceedances for the seven metals were also evaluated over the 11-year time period to provide insight into potential metal toxicity to resident benthic communities. In addition, the bioavailability of metals in sediments was also determined by calculating Simultaneous Extracted Metal/Acid Volatle Sulfide (SEM/AVS) ratios to allow an additional assessment of toxicity. Regulatory implications of this data set and the role of metal toxicity are also discussed. Stream-wide temporal trend analysis showed no statistically significant trends for any of the metals. However, spatial analysis for several sites located near storm drains did show a significant increase for most metals over the 11-year period. TEL exceedances during the 7 years of sampling, spanning 2006-2016, were reported for all metals with the number of exceedances ranging from 47 for copper and zinc to 1 for lead. A spatial analysis showed that the highest number of TEL exceedances and the highest number of SEM/AVS ratios greater than one with at least one metal exceeding a TEL occurred at upstream sites. The potentially toxic metal concentrations reported in Pleasant Grove Creek should be used in the 303 (d) listing process for impaired water bodies in California.

  12. Spatial Variability of Soil-Water Storage in the Southern Sierra Critical Zone Observatory: Measurement and Prediction

    Science.gov (United States)

    Oroza, C.; Bales, R. C.; Zheng, Z.; Glaser, S. D.

    2017-12-01

    Predicting the spatial distribution of soil moisture in mountain environments is confounded by multiple factors, including complex topography, spatial variably of soil texture, sub-surface flow paths, and snow-soil interactions. While remote-sensing tools such as passive-microwave monitoring can measure spatial variability of soil moisture, they only capture near-surface soil layers. Large-scale sensor networks are increasingly providing soil-moisture measurements at high temporal resolution across a broader range of depths than are accessible from remote sensing. It may be possible to combine these in-situ measurements with high-resolution LIDAR topography and canopy cover to estimate the spatial distribution of soil moisture at high spatial resolution at multiple depths. We study the feasibility of this approach using six years (2009-2014) of daily volumetric water content measurements at 10-, 30-, and 60-cm depths from the Southern Sierra Critical Zone Observatory. A non-parametric, multivariate regression algorithm, Random Forest, was used to predict the spatial distribution of depth-integrated soil-water storage, based on the in-situ measurements and a combination of node attributes (topographic wetness, northness, elevation, soil texture, and location with respect to canopy cover). We observe predictable patterns of predictor accuracy and independent variable ranking during the six-year study period. Predictor accuracy is highest during the snow-cover and early recession periods but declines during the dry period. Soil texture has consistently high feature importance. Other landscape attributes exhibit seasonal trends: northness peaks during the wet-up period, and elevation and topographic-wetness index peak during the recession and dry period, respectively.

  13. FASHION TREND FOR A SILHOUETTE: BALENCIAGA CASE

    OpenAIRE

    ERTÜRK, Nilay; özüdoğru, şakir

    2014-01-01

    Fashion, in broad and accepted definition, is any temporary preference or a temporary new thing in any area of human life, which prevails for a certain period of time. The issue of how fashionable products would look like in a particular season is discussed under the concept of fashion trends. The main purpose of this study is to discuss the concept of fashion trends and the studies on predictions in fashion trends, to conduct a sample trend survey for a silhouette and observe whether or not ...

  14. Evaluation and application of multi-decadal visibility data for trend analysis of atmospheric haze

    Directory of Open Access Journals (Sweden)

    C. Li

    2016-03-01

    Full Text Available There are few multi-decadal observations of atmospheric aerosols worldwide. This study applies global hourly visibility (Vis observations at more than 3000 stations to investigate historical trends in atmospheric haze over 1945–1996 for the US, and over 1973–2013 for Europe and eastern Asia. A comprehensive data screening and processing framework is developed and applied to minimize uncertainties and construct monthly statistics of inverse visibility (1/Vis. This data processing includes removal of relatively clean cases with high uncertainty, and change point detection to identify and separate methodological discontinuities such as the introduction of instrumentation. Although the relation between 1/Vis and atmospheric extinction coefficient (bext varies across different stations, spatially coherent trends of the screened 1/Vis data exhibit consistency with the temporal evolution of collocated aerosol measurements, including the bext trend of −2.4 % yr−1 (95 % CI: −3.7, −1.1 % yr−1 vs. 1/Vis trend of −1.6 % yr−1 (95 % CI: −2.4, −0.8 % yr−1 over the US for 1989–1996, and the fine aerosol mass (PM2.5 trend of −5.8 % yr−1 (95 % CI: −7.8, −4.2 % yr−1 vs. 1/Vis trend of −3.4 % yr−1 (95 % CI: −4.4, −2.4 % yr−1 over Europe for 2006–2013. Regional 1/Vis and Emissions Database for Global Atmospheric Research (EDGAR sulfur dioxide (SO2 emissions are significantly correlated over the eastern US for 1970–1995 (r = 0.73, over Europe for 1973–2008 (r ∼ 0.9 and over China for 1973–2008 (r ∼ 0.9. Consistent "reversal points" from increasing to decreasing in SO2 emission data are also captured by the regional 1/Vis time series (e.g., late 1970s for the eastern US, early 1980s for western Europe, late 1980s for eastern Europe, and mid 2000s for China. The consistency of 1/Vis trends with other in situ measurements and emission data demonstrates promise in applying these quality assured 1/Vis data

  15. Chemical trends in ocean islands explained by plume–slab interaction

    Science.gov (United States)

    Dannberg, Juliane; Gassmöller, Rene

    2018-04-01

    Earth's surface shows many features, of which the genesis can be understood only through their connection with processes in Earth's deep interior. Recent studies indicate that spatial geochemical patterns at oceanic islands correspond to structures in the lowermost mantle inferred from seismic tomographic models. This suggests that hot, buoyant upwellings can carry chemical heterogeneities from the deep lower mantle toward the surface, providing a window to the composition of the lowermost mantle. The exact nature of this link between surface and deep Earth remains debated and poorly understood. Using computational models, we show that subducted slabs interacting with dense thermochemical piles can trigger the ascent of hot plumes that inherit chemical gradients present in the lowermost mantle. We identify two key factors controlling this process: (i) If slabs induce strong lower-mantle flow toward the edges of these piles where plumes rise, the pile-facing side of the plume preferentially samples material originating from the pile, and bilaterally asymmetric chemical zoning develops. (ii) The composition of the melt produced reflects this bilateral zoning if the overlying plate moves roughly perpendicular to the chemical gradient in the plume conduit. Our results explain some of the observed geochemical trends of oceanic islands and provide insights into how these trends may originate.

  16. A Comparative Study of Spatial Aggregation Methodologies under the BioEarth Framework

    Science.gov (United States)

    Chandrasekharan, B.; Rajagopalan, K.; Malek, K.; Stockle, C. O.; Adam, J. C.; Brady, M.

    2014-12-01

    The increasing probability of water resource scarcity due to climate change has highlighted the need for adopting an economic focus in modelling water resource uses. Hydro-economic models, developed by integrating economic optimization with biophysical crop models, are driven by the economic value of water, revealing it's most efficient uses and helping policymakers evaluate different water management strategies. One of the challenges in integrating biophysical models with economic models is the difference in the spatial scales in which they operate. Biophysical models that provide crop production functions typically run at smaller scale than economic models, and substantial spatial aggregation is required. However, any aggregation introduces a bias, i.e., a discrepancy between the functional value at the higher spatial scale and the value at the spatial scale of the aggregated units. The objective of this work is to study the sensitivity of net economic benefits in the Yakima River basin (YRB) to different spatial aggregation methods for crop production functions. The spatial aggregation methodologies that we compare involve agro-ecological zones (AEZs) and aggregation levels that reflect water management regimes (e.g. irrigation districts). Aggregation bias can distort the underlying data and result in extreme solutions. In order to avoid this we use an economic optimization model that incorporates the synthetic and historical crop mixes approach (Onal & Chen, 2012). This restricts the solutions between the weighted averages of historical and simulated feasible planting decisions, with the weights associated with crop mixes being treated as endogenous variables. This study is focused on 5 major irrigation districts of the YRB in the Pacific Northwest US. The biophysical modeling framework we use, BioEarth, includes the coupled hydrology and crop growth model, VIC-Cropsyst and an economic optimization model. Preliminary findings indicate that the standard approach

  17. Spatial analysis for the epidemiological study of cardiovascular diseases: A systematic literature search.

    Science.gov (United States)

    Mena, Carlos; Sepúlveda, Cesar; Fuentes, Eduardo; Ormazábal, Yony; Palomo, Iván

    2018-05-07

    Cardiovascular diseases (CVDs) are the primary cause of death and disability in de world, and the detection of populations at risk as well as localization of vulnerable areas is essential for adequate epidemiological management. Techniques developed for spatial analysis, among them geographical information systems and spatial statistics, such as cluster detection and spatial correlation, are useful for the study of the distribution of the CVDs. These techniques, enabling recognition of events at different geographical levels of study (e.g., rural, deprived neighbourhoods, etc.), make it possible to relate CVDs to factors present in the immediate environment. The systemic literature presented here shows that this group of diseases is clustered with regard to incidence, mortality and hospitalization as well as obesity, smoking, increased glycated haemoglobin levels, hypertension physical activity and age. In addition, acquired variables such as income, residency (rural or urban) and education, contribute to CVD clustering. Both local cluster detection and spatial regression techniques give statistical weight to the findings providing valuable information that can influence response mechanisms in the health services by indicating locations in need of intervention and assignment of available resources.

  18. A Correlational Study of Seven Projective Spatial Structures with Regard to the Phases of the MOON^

    Science.gov (United States)

    Wellner, Karen Linette

    1995-01-01

    This study investigated the relationship between projective spatial structures and the ability to construct a scientific model. In addition, gender-related performance and the influence of prior astronomy experience on task success were evaluated. Sixty-one college science undergraduates were individually administered Piagetian tasks to assess for projective spatial structures and the ability to set up a phases of the moon model. The spatial tasks included: (a) Mountains task (coordination of perspectives); (b) Railroad task (size and intervals of objects with increasing distance); (c) Telephone Poles task (masking and ordering objects); and (d) Shadows task (spatial relationships between an object and its shadow, dependent upon the object's orientation). Cramer coefficient analyses indicated that significant relationships existed between Moon task and spatial task success. In particular, the Shadows task, requiring subjects to draw shadows of objects in different orientations, proved most difficult and was most strongly associated with with a subject's understanding of lunar phases. Chi-square tests for two independent samples were used to analyze gender performance differences on each of the Ave tasks. Males performed significantly better at a.05 significance level in regard to the Shadows task and the Moon task. Chi-square tests for two independent samples showed no significant difference in Moon task performance between subjects with astronomy or Earth science coursework, and those without such science classroom experience. Overall, only six subjects passed all seven projective spatial structure tasks. Piaget (1967) contends that concrete -operational spatial structures must be established before an individual is able to develop formal-operational patterns of thinking. The results of this study indicate that 90% of the interviewed science majors are still operating at the concrete-operational level. Several educational implications were drawn from this study

  19. Relation between trends in late middle age mortality and trends in old age mortality--is there evidence for mortality selection?

    NARCIS (Netherlands)

    Janssen, F.; Peeters, A.; Mackenbach, J. P.; Kunst, A. E.

    2005-01-01

    STUDY OBJECTIVE: To test whether mortality selection was a dominant factor in determining trends in old age mortality, by empirically studying the existence of a negative correlation between trends in late middle age mortality and trends in old age mortality among the same cohorts. DESIGN AND

  20. Spatial-temporal variations of natural suitability of human settlement environment in the Three Gorges Reservoir Area—A case study in Fengjie County, China

    Science.gov (United States)

    Luo, Jieqiong; Zhou, Tinggang; Du, Peijun; Xu, Zhigang

    2018-01-01

    With rapid environmental degeneration and socio-economic development, the human settlement environment (HSE) has experienced dramatic changes and attracted attention from different communities. Consequently, the spatial-temporal evaluation of natural suitability of the human settlement environment (NSHSE) has become essential for understanding the patterns and dynamics of HSE, and for coordinating sustainable development among regional populations, resources, and environments. This study aims to explore the spatialtemporal evolution of NSHSE patterns in 1997, 2005, and 2009 in Fengjie County near the Three Gorges Reservoir Area (TGRA). A spatially weighted NSHSE model was established by integrating multi-source data (e.g., census data, meteorological data, remote sensing images, DEM data, and GIS data) into one framework, where the Ordinary Least Squares (OLS) linear regression model was applied to calculate the weights of indices in the NSHSE model. Results show that the trend of natural suitability has been first downward and then upward, which is evidenced by the disparity of NSHSE existing in the south, north, and central areas of Fengjie County. Results also reveal clustered NSHSE patterns for all 30 townships. Meanwhile, NSHSE has significant influence on population distribution, and 71.49% of the total population is living in moderate and high suitable districts.