WorldWideScience

Sample records for based time trends

  1. Piecewise Trend Approximation: A Ratio-Based Time Series Representation

    Directory of Open Access Journals (Sweden)

    Jingpei Dan

    2013-01-01

    Full Text Available A time series representation, piecewise trend approximation (PTA, is proposed to improve efficiency of time series data mining in high dimensional large databases. PTA represents time series in concise form while retaining main trends in original time series; the dimensionality of original data is therefore reduced, and the key features are maintained. Different from the representations that based on original data space, PTA transforms original data space into the feature space of ratio between any two consecutive data points in original time series, of which sign and magnitude indicate changing direction and degree of local trend, respectively. Based on the ratio-based feature space, segmentation is performed such that each two conjoint segments have different trends, and then the piecewise segments are approximated by the ratios between the first and last points within the segments. To validate the proposed PTA, it is compared with classical time series representations PAA and APCA on two classical datasets by applying the commonly used K-NN classification algorithm. For ControlChart dataset, PTA outperforms them by 3.55% and 2.33% higher classification accuracy and 8.94% and 7.07% higher for Mixed-BagShapes dataset, respectively. It is indicated that the proposed PTA is effective for high dimensional time series data mining.

  2. Symbolic representation based on trend features for knowledge discovery in long time series

    Institute of Scientific and Technical Information of China (English)

    Hong YIN; Shu-qiang YANG; Xiao-qian ZHU; Shao-dong MA; Lu-min ZHANG

    2015-01-01

    The symbolic representation of time series has attracted much research interest recently. The high dimensionality typical of the data is challenging, especially as the time series becomes longer. The wide distribution of sensors collecting more and more data exacerbates the problem. Representing a time series effectively is an essential task for decision-making activities such as classification, prediction, and knowledge discovery. In this paper, we propose a new symbolic representation method for long time series based on trend features, called trend feature symbolic approximation (TFSA). The method uses a two-step mechanism to segment long time series rapidly. Unlike some previous symbolic methods, it focuses on retaining most of the trend features and patterns of the original series. A time series is represented by trend symbols, which are also suitable for use in knowledge discovery, such as association rules mining. TFSA provides the lower bounding guarantee. Experimental results show that, compared with some previous methods, it not only has better segmentation efficiency and classification accuracy, but also is applicable for use in knowledge discovery from time series.

  3. Analysis of the Main Factors Influencing Food Production in China Based on Time Series Trend Chart

    Institute of Scientific and Technical Information of China (English)

    Shuangjin; WANG; Jianying; LI

    2014-01-01

    Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effective irrigation area,the affected area,total machinery power,food production cost index,food production price index,financial funds for supporting agriculture,farmers and countryside),and put them into categories of material input,resources and environment,and policy factors. Using the factor analysis,we carry out the multi-angle analysis of these typical influencing factors one by one through the time series trend chart. It is found that application rate of chemical fertilizer,the growing area of food crops and drought-affected area become the key factors affecting food production. On this basis,we set forth the corresponding recommendations for improving the comprehensive food production capacity.

  4. Modeling pollen time series using seasonal-trend decomposition procedure based on LOESS smoothing

    Science.gov (United States)

    Rojo, Jesús; Rivero, Rosario; Romero-Morte, Jorge; Fernández-González, Federico; Pérez-Badia, Rosa

    2016-08-01

    Analysis of airborne pollen concentrations provides valuable information on plant phenology and is thus a useful tool in agriculture—for predicting harvests in crops such as the olive and for deciding when to apply phytosanitary treatments—as well as in medicine and the environmental sciences. Variations in airborne pollen concentrations, moreover, are indicators of changing plant life cycles. By modeling pollen time series, we can not only identify the variables influencing pollen levels but also predict future pollen concentrations. In this study, airborne pollen time series were modeled using a seasonal-trend decomposition procedure based on LOcally wEighted Scatterplot Smoothing (LOESS) smoothing (STL). The data series—daily Poaceae pollen concentrations over the period 2006-2014—was broken up into seasonal and residual (stochastic) components. The seasonal component was compared with data on Poaceae flowering phenology obtained by field sampling. Residuals were fitted to a model generated from daily temperature and rainfall values, and daily pollen concentrations, using partial least squares regression (PLSR). This method was then applied to predict daily pollen concentrations for 2014 (independent validation data) using results for the seasonal component of the time series and estimates of the residual component for the period 2006-2013. Correlation between predicted and observed values was r = 0.79 (correlation coefficient) for the pre-peak period (i.e., the period prior to the peak pollen concentration) and r = 0.63 for the post-peak period. Separate analysis of each of the components of the pollen data series enables the sources of variability to be identified more accurately than by analysis of the original non-decomposed data series, and for this reason, this procedure has proved to be a suitable technique for analyzing the main environmental factors influencing airborne pollen concentrations.

  5. Analysis of the development trend of China’s business administration based on time series

    OpenAIRE

    Jiang Rui

    2016-01-01

    On the general direction of the economic system, China is in a crucial period of the establishment of the modern enterprise system and reform of the macroeconomic system, and a lot of high-quality business administration talents are required to make China’s economy be stably developed. This paper carries out time series analysis of the development situation of China’s business administration major: on the whole, the society currently presents an upward trend on the demand for the business adm...

  6. Multi-Sliding Time Windows Based Changing Trend of Mean Temperature and Its Association with the Global-Warming Hiatus

    Institute of Scientific and Technical Information of China (English)

    石岩; 翟盘茂; 江志红

    2016-01-01

    Based on three global annual mean surface temperature time series and three Chinese annual mean surface air temperature time series, climate change trends on multiple timescales are analyzed by using the trend estimation method of multi-sliding time windows. The results are used to discuss the so-called global-warming hiatus during 1998–2012. It is demonstrated that different beginning and end times have an obvious effect on the results of the trend estimation, and the implications are particularly large when using a short window. The global-warming hiatus during 1998–2012 is the result of viewing temperature series on short timescales;and the events similar to it, or the events with even cold tendencies, have actually occurred many times in history. Therefore, the global-warming hiatus is likely to be a periodical feature of the long-term temperature change. It mainly reflects the decadal variability of temperature, and such a phenomenon in the short term does not alter the overall warming trend in the long term.

  7. Multi-sliding time windows based changing trend of mean temperature and its association with the global-warming hiatus

    Science.gov (United States)

    Shi, Yan; Zhai, Panmao; Jiang, Zhihong

    2016-04-01

    Based on three global annual mean surface temperature time series and three Chinese annual mean surface air temperature time series, climate change trends on multiple timescales are analyzed by using the trend estimation method of multi-sliding time windows. The results are used to discuss the so-called global-warming hiatus during 1998-2012. It is demonstrated that different beginning and end times have an obvious effect on the results of the trend estimation, and the implications are particularly large when using a short window. The global-warming hiatus during 1998-2012 is the result of viewing temperature series on short timescales; and the events similar to it, or the events with even cold tendencies, have actually occurred many times in history. Therefore, the global-warming hiatus is likely to be a periodical feature of the long-term temperature change. It mainly reflects the decadal variability of temperature, and such a phenomenon in the short term does not alter the overall warming trend in the long term.

  8. Doctors’ enjoyment of their work and satisfaction with time available for leisure: UK time trend questionnaire-based study

    Science.gov (United States)

    Surman, Geraldine; Lambert, Trevor W; Goldacre, Michael

    2016-01-01

    Introduction Doctors’ job satisfaction is important to the health service to ensure commitment, effective training, service provision and retention. Job satisfaction matters to doctors for their personal happiness, fulfilment, service to patients and duty to employers. Monitoring job satisfaction trends informs workforce planning. Materials and methods We surveyed UK-trained doctors up to 5 years after graduation for six graduation year cohorts: 1996, 1999, 2002, 2005, 2008, 2012. Doctors scored their job enjoyment (Enjoyment) and satisfaction with time outside work (Leisure) on a scale from 1 (lowest enjoyment/satisfaction) to 10 (highest). Results Overall, 47% had a high level of Enjoyment (scores 8–10) 1 year after graduation and 56% after 5 years. For Leisure, the corresponding figures were 19% and 37% at 1 and 5 years, respectively. For Leisure at 1 year, high scores were given by about 10% in the 1990s, rising to about 25% in the mid-2000s. Low scores (1–3) for Enjoyment were given by 15% of qualifiers of 1996, falling to 5% by 2008; corresponding figures for Leisure were 42% and 19%. At 5 years, the corresponding figures were 6% and 4%, and 23% and 17%. Enjoyment and Leisure were scored higher by general practitioners than doctors in other specialties. Both measures varied little by sex, ethnicity or medical school attended. Conclusions Scores for Enjoyment were generally high; those for Leisure were lower. Policy initiatives should address why this aspect of satisfaction is low, particularly in the first year after graduation but also among hospital doctors 5 years after graduation. PMID:26783328

  9. Contrasting trends in light pollution across Europe based on satellite observed night time lights

    Science.gov (United States)

    Bennie, Jonathan; Davies, Thomas W.; Duffy, James P.; Inger, Richard; Gaston, Kevin J.

    2014-01-01

    Since the 1970s nighttime satellite images of the Earth from space have provided a striking illustration of the extent of artificial light. Meanwhile, growing awareness of adverse impacts of artificial light at night on scientific astronomy, human health, ecological processes and aesthetic enjoyment of the night sky has led to recognition of light pollution as a significant global environmental issue. Links between economic activity, population growth and artificial light are well documented in rapidly developing regions. Applying a novel method to analysis of satellite images of European nighttime lights over 15 years, we show that while the continental trend is towards increasing brightness, some economically developed regions show more complex patterns with large areas decreasing in observed brightness over this period. This highlights that opportunities exist to constrain and even reduce the environmental impact of artificial light pollution while delivering cost and energy-saving benefits.

  10. Doctors' enjoyment of their work and satisfaction with time available for leisure: UK time trend questionnaire-based study.

    OpenAIRE

    Surman, G; Lambert, TW; Goldacre, M

    2016-01-01

    Introduction Doctors’ job satisfaction is important to the health service to ensure commitment, effective training, service provision and retention. Job satisfaction matters to doctors for their personal happiness, fulfilment, service to patients and duty to employers. Monitoring job satisfaction trends informs workforce planning. Materials and methods We surveyed UK-trained doctors up to 5 years after graduation for six graduation year cohorts: 1996, 1999, 2002, 2005, 2008, 2012. Doctors sco...

  11. Trend prediction of chaotic time series

    Institute of Scientific and Technical Information of China (English)

    Li Aiguo; Zhao Cai; Li Zhanhuai

    2007-01-01

    To predict the trend of chaotic time series in time series analysis and time series data mining fields, a novel predicting algorithm of chaotic time series trend is presented, and an on-line segmenting algorithm is proposed to convert a time series into a binary string according to ascending or descending trend of each subsequence. The on-line segmenting algorithm is independent of the prior knowledge about time series. The naive Bayesian algorithm is then employed to predict the trend of chaotic time series according to the binary string. The experimental results of three chaotic time series demonstrate that the proposed method predicts the ascending or descending trend of chaotic time series with few error.

  12. Potentially avoidable hospitalizations in five European countries in 2009 and time trends from 2002 to 2009 based on administrative data

    DEFF Research Database (Denmark)

    Thygesen, Lau C; Christiansen, Terkel; Garcia-Armesto, Sandra;

    2015-01-01

    INTRODUCTION: Potentially avoidable hospitalizations in chronic conditions are used to evaluate health-care performance. However, evidence comparing different countries at small geographical areas is still scarce. The aim of the present study is to describe and discuss differences in rates and time......-trends across health-care areas from five European countries. METHODS: Observational, ecological study, on virtually all discharges produced in five European countries between 2002 and 2009. Potentially avoidable hospitalizations were operationally defined as a joint indicator composed of six chronic conditions...

  13. Time trends in human fecundability in Sweden

    DEFF Research Database (Denmark)

    Scheike, Thomas H; Rylander, Lars; Carstensen, Lisbeth;

    2008-01-01

    BACKGROUND: Trends in biologic fertility are elusive. Possible negative trends in male reproductive health are still debated, and their effect on human fertility might be negligible. Time-to-pregnancy (TTP) is a functional measure of couple fecundability. METHODS: We analyzed data on TTP among 832......,000 primiparous women 20 years of age and older in the nationwide Swedish Medical Birth Registry from 1983 through 2002. This age restriction led to an exclusion of 10% of primiparous pregnancies. Subfertility (TTP > or =1 year) was analyzed as a function of maternal age, calendar time at initiation of attempt...... increased with age, except that for women in their late 1930s, an apparent decrease was observed, particularly among the early cohorts. CONCLUSION: We found decreasing subfertility over time. We speculate that these patterns might be related to a Sweden-specific decrease over time in sexually transmitted...

  14. Trend prediction of chaotic time series

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Trend prediction of chaotic ti me series is anin-teresting probleminti me series analysis andti me se-ries data mining(TSDM)fields[1].TSDM-basedmethods can successfully characterize and predictcomplex,irregular,and chaotic ti me series.Somemethods have been proposed to predict the trend ofchaotic ti me series.In our knowledge,these meth-ods can be classified into t wo categories as follows.The first category is based on the embeddedspace[2-3],where rawti me series data is mapped to areconstructed phase spac...

  15. In search of functional association from time-series microarray data based on the change trend and level of gene expression

    Directory of Open Access Journals (Sweden)

    Zeng An-Ping

    2006-02-01

    Full Text Available Abstract Background The increasing availability of time-series expression data opens up new possibilities to study functional linkages of genes. Present methods used to infer functional linkages between genes from expression data are mainly based on a point-to-point comparison. Change trends between consecutive time points in time-series data have been so far not well explored. Results In this work we present a new method based on extracting main features of the change trend and level of gene expression between consecutive time points. The method, termed as trend correlation (TC, includes two major steps: 1, calculating a maximal local alignment of change trend score by dynamic programming and a change trend correlation coefficient between the maximal matched change levels of each gene pair; 2, inferring relationships of gene pairs based on two statistical extraction procedures. The new method considers time shifts and inverted relationships in a similar way as the local clustering (LC method but the latter is merely based on a point-to-point comparison. The TC method is demonstrated with data from yeast cell cycle and compared with the LC method and the widely used Pearson correlation coefficient (PCC based clustering method. The biological significance of the gene pairs is examined with several large-scale yeast databases. Although the TC method predicts an overall lower number of gene pairs than the other two methods at a same p-value threshold, the additional number of gene pairs inferred by the TC method is considerable: e.g. 20.5% compared with the LC method and 49.6% with the PCC method for a p-value threshold of 2.7E-3. Moreover, the percentage of the inferred gene pairs consistent with databases by our method is generally higher than the LC method and similar to the PCC method. A significant number of the gene pairs only inferred by the TC method are process-identity or function-similarity pairs or have well-documented biological

  16. A practical procedure for the selection of time-to-failure models based on the assessment of trends in maintenance data

    Energy Technology Data Exchange (ETDEWEB)

    Louit, D.M. [Komatsu Chile, Av. Americo Vespucio 0631, Quilicura, Santiago (Chile)], E-mail: rpascual@ing.puc.cl; Pascual, R. [Centro de Mineria, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, Santiago (Chile); Jardine, A.K.S. [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King' s College Road, Toronto, Ont., M5S 3G8 (Canada)

    2009-10-15

    Many times, reliability studies rely on false premises such as independent and identically distributed time between failures assumption (renewal process). This can lead to erroneous model selection for the time to failure of a particular component or system, which can in turn lead to wrong conclusions and decisions. A strong statistical focus, a lack of a systematic approach and sometimes inadequate theoretical background seem to have made it difficult for maintenance analysts to adopt the necessary stage of data testing before the selection of a suitable model. In this paper, a framework for model selection to represent the failure process for a component or system is presented, based on a review of available trend tests. The paper focuses only on single-time-variable models and is primarily directed to analysts responsible for reliability analyses in an industrial maintenance environment. The model selection framework is directed towards the discrimination between the use of statistical distributions to represent the time to failure ('renewal approach'); and the use of stochastic point processes ('repairable systems approach'), when there may be the presence of system ageing or reliability growth. An illustrative example based on failure data from a fleet of backhoes is included.

  17. Time Trends over 16 Years in Incidence-Rates of Autism Spectrum Disorders across the Lifespan Based on Nationwide Danish Register Data

    Science.gov (United States)

    Jensen, Christina Mohr; Steinhausen, Hans-Christoph; Lauritsen, Marlene Briciet

    2014-01-01

    This study investigated time trends and associated factors of incidence rates of diagnosed autism spectrum disorders (ASD) across the lifespan from 1995 to 2010, using data from the Danish Psychiatric Central Research Registry. First time diagnosis of childhood autism, atypical autism, Asperger's syndrome, or pervasive developmental…

  18. Seasonal adjustment methods and real time trend-cycle estimation

    CERN Document Server

    Bee Dagum, Estela

    2016-01-01

    This book explores widely used seasonal adjustment methods and recent developments in real time trend-cycle estimation. It discusses in detail the properties and limitations of X12ARIMA, TRAMO-SEATS and STAMP - the main seasonal adjustment methods used by statistical agencies. Several real-world cases illustrate each method and real data examples can be followed throughout the text. The trend-cycle estimation is presented using nonparametric techniques based on moving averages, linear filters and reproducing kernel Hilbert spaces, taking recent advances into account. The book provides a systematical treatment of results that to date have been scattered throughout the literature. Seasonal adjustment and real time trend-cycle prediction play an essential part at all levels of activity in modern economies. They are used by governments to counteract cyclical recessions, by central banks to control inflation, by decision makers for better modeling and planning and by hospitals, manufacturers, builders, transportat...

  19. Estimating Time-varying Trends from Geodetic Time Series

    Science.gov (United States)

    Didova, O.; Gunter, B. C.; Riva, R.; Klees, R.; Roese-Koerner, L.

    2015-12-01

    Modeling signal and noise in geodetic time series is crucial for the proper interpretation of the data. Depending on how the functional and stochastic models are defined, the estimated trend and corresponding uncertainties can vary significantly, emphasizing the need for a robust tool for their estimation. In this study, instead of using the traditional deterministic approach where seasonal signals are estimated with fixed amplitudes and phases and the trend is assumed to be linear, an alternate approach is presented in which these signals are modeled stochastically. The benefit of this approach is that it allows for physically natural variations of the various signal constituents over time. To accomplish this, state space models are defined and solved through the use of a Kalman filter. Since the appropriate choice of the noise parameters is at the heart of the proposed approach, a robust method for their estimation is developed. The performance of the methodology is demonstrated using Gravity Recovery and Climate Experiment (GRACE) and the Global Positioning System (GPS) data at the CAS1 station located in East Antarctica and compared to commonly used least-squares adjustment techniques. The results show that the developed technique allows for a more reliable trend estimation as well as for more physically valuable interpretations while validating independent geodetic observing systems. Moreover, the results suggest that the pursued methodology should become the standard in particular when analyzing climatologic data.

  20. Time Trends in Bullying Behavior in Italy

    Science.gov (United States)

    Vieno, Alessio; Lenzi, Michela; Gini, Gianluca; Pozzoli, Tiziana; Cavallo, Franco; Santinello, Massimo

    2015-01-01

    Background: Given the severity of outcomes associated with involvement in bullying and the resources spent in an effort to reduce its prevalence, it is important to investigate trends in the bullying's occurrence. The main aim of this study was to identify trends from 2002 to 2010 in prevalence of bullying and victimization among Italian…

  1. Recent secular trends in pubertal timing

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Mouritsen, Annette; Aksglaede, Lise;

    2012-01-01

    changes. The recent pubertal trends have resulted in a concomitant lowering of the lower limit of normality of the pubertal onset. However, evidence suggests that age at the gonadotropin and sex steroid surges have not changed. Thus, it looks as if an increasing proportion of contemporary early pubertal...

  2. Three measures of longevity: time trends and record values

    DEFF Research Database (Denmark)

    Canudas-Romo, V

    2010-01-01

    This article examines the trend over time in the measures of “typical” longevity experienced by members of a population: life expectancy at birth, and the median and modal ages at death. The article also analyzes trends in record values observed for all three measures. The record life expectancy...... time from a dominance of child mortality reductions to a dominance of adult mortality reductions, which became evident by studying trends in the record modal age at death....

  3. “Once upon a Time in the Mediterranean” Long Term Trends of Mediterranean Fisheries Resources Based on Fishers’ Traditional Ecological Knowledge

    Science.gov (United States)

    Damalas, Dimitrios; Maravelias, Christos D.; Osio, Giacomo C.; Maynou, Francesc; Sbrana, Mario; Sartor, Paolo

    2015-01-01

    We investigate long-term changes in the Mediterranean marine resources driving the trawl fisheries by analysing fishers’ perceptions (Traditional Ecological Knowledge, TEK) throughout the Mediterranean Sea during the last 80 years. To this end, we conducted an extended set of interviews with experienced fishers that enabled us to classify species (or taxa) as ‘decreasing’ or ‘increasing’ both in terms of abundance, as well as average size in the catch. The aspect that most clearly emerged in all the investigated areas over time was the notable increase of fishing capacity indicators, such as engine power and fishing depth range. Atlantic mackerel, poor cod, scorpionfishes, striped seabream, and John Dory demonstrated a decreasing trend in the fishers’ perceived abundance, while Mediterranean parrotfish, common pandora, cuttlefish, blue and red shrimp, and mullets gave indications of an increasing temporal trend. Although, as a rule, trawler captains did not report any cataclysmic changes (e.g. extinctions), when they were invited to estimate total catches, a clear decreasing pattern emerged; this being a notable finding taking into account the steep escalation of fishing efficiency during the past century. The overall deteriorating status of stocks in most Mediterranean regions calls for responsible management and design of rebuilding plans. This should include historical information accounting for past exploitation patterns that could help defining a baseline of fish abundance prior to heavy industrial fisheries exploitation. PMID:25781459

  4. JMS at 50 : trends over time.

    OpenAIRE

    Clark, T.; Wright, M; Iskoujina, Z.; Garnett, P

    2014-01-01

    We present an analysis of the articles published in the Journal of Management Studies since its inception to assess to what extent JMS has: maintained its leading international ranking; maintained its founding mission as a broad based management journal; and remained a broad based management journal compared to other general management journals. In terms of its impact factor and citations despite reaching a low point in 2001, we find that JMS today ranks higher than it has ever done throughou...

  5. Time trends and mechanisms of soil acidification.

    NARCIS (Netherlands)

    Wesselink, L.G.

    1994-01-01

    The effects of acid atmospheric deposition on forest ecosystems have been studied intensively in the past two decades. Measurements of element budgets in forested ecosystems throughout the world have shown that acid deposition may deplete stores of exchangeable base cations in the soil, decrease the

  6. Time Delay Systems Methods, Applications and New Trends

    CERN Document Server

    Vyhlídal, Tomáš; Niculescu, Silviu-Iulian; Pepe, Pierdomenico

    2012-01-01

    This volume is concerned with the control and dynamics of time delay systems; a research field with at least six-decade long history that has been very active especially in the past two decades. In parallel to the new challenges emerging from engineering, physics, mathematics, and economics, the volume covers several new directions including topology induced stability, large-scale interconnected systems, roles of networks in stability, and new trends in predictor-based control and consensus dynamics. The associated applications/problems are described by highly complex models, and require solving inverse problems as well as the development of new theories, mathematical tools, numerically-tractable algorithms for real-time control. The volume, which is targeted to present these developments in this rapidly evolving field, captures a careful selection of the most recent papers contributed by experts and collected under five parts: (i) Methodology: From Retarded to Neutral Continuous Delay Models, (ii) Systems, S...

  7. Time trend in diagnosing dementia in secondary care

    DEFF Research Database (Denmark)

    Phung, Thien Kieu Thi; Waltoft, Berit Lindum; Kessing, Lars Vedel;

    2010-01-01

    To study the trend of diagnosing dementia in the secondary health care sector over time, we conducted a nationwide longitudinal study of the incidence and prevalence of registered dementia diagnoses in the Danish national hospital registers.......To study the trend of diagnosing dementia in the secondary health care sector over time, we conducted a nationwide longitudinal study of the incidence and prevalence of registered dementia diagnoses in the Danish national hospital registers....

  8. Real-time trend monitoring of gas compressor stations

    Energy Technology Data Exchange (ETDEWEB)

    Van Hardeveld, T. (Nova, an Alberta Corp., AB (Canada))

    1991-02-01

    The authors' company has developed a machinery health monitoring system (MHealth) for short-term and long-term historical trending and analysis of data from its 40 gas compressor stations. The author discusses the benefits of real-time trending in troubleshooting operations, in preventative maintenance scheduling and cites specific applications in the startup operations of several new gas compressor/centrifugal compressor units.

  9. Time of emergence of trends in ocean biogeochemistry

    Science.gov (United States)

    Keller, Kathrin M.; Joos, Fortunat; Raible, Christoph C.

    2015-04-01

    The detection of forced trends in biogeochemical cycles and ecosystems is a challenge. A major issue is the presence of natural variability which has the potential to enhance or mask trends over decadal timescales. The successful detection of trend signals is thus a signal-to-noise (S/N) problem, i.e., the signal has to be of a magnitude that durably exceeds the envelope of background variability. One possible measure to estimate this is the time of emergence (ToE) of a signal, that is, the point in time at which the ratio S/N exceeds a certain threshold. We use historical simulations from 17 Earth System Models to investigate the ToE of trends in surface ocean biogeochemistry. For maximum comparability with the available observations, we focus on dissolved inorganic carbon (DIC), pCO2 and pH, and sea-surface temperature (SST). We find that signals in ocean biogeochemical variables emerge on much shorter timescales than the physical variable SST. The ToE patterns of pCO2 and pH are spatially very similar to DIC, yet the trends emerge much faster - after roughly 12 years for the majority of the global ocean area, compared to between 10-30 years for DIC and 45-90 years for SST. In general, the background noise is of higher importance in determining ToE than the strength of the trend signal. In areas with high natural variability, even strong trends both in the physical climate and carbon cycle system are masked by variability over decadal timescales. In contrast to the trend, natural variability is affected by the seasonal cycle. This has important implications for observations, since it implies that intra-annual variability could question the representativeness of irregularly seasonal sampled measurements for the entire year and, thus, the interpretation of observed trends.

  10. Trends in puberty timing in humans and environmental modifiers

    DEFF Research Database (Denmark)

    Toppari, Jorma; Juul, Anders

    2010-01-01

    Secular trends in timing of puberty appear to continue although under-nutrition has not been any longer a limiting factor for pubertal development. Now obesity and other environmental reasons have been suspected to cause this trend, and endocrine disrupting chemicals have become into focus as...... possible contributors. Epidemiological studies on endocrine disrupters are still scarce and show only weak associations between exposures and timing of puberty. Since genetic background explains 50-80% of variability in the timing of puberty, it is not surprising that the observed environmental effects are...... rather modest when individual exposures are assessed. Despite that, some exposures have been reported to be associated to early (e.g., polybrominated biphenyls) or delayed (e.g., lead) puberty. Here we shortly review the available data on recent trends in timing of puberty and the possible role of...

  11. Trends in puberty timing in humans and environmental modifiers

    DEFF Research Database (Denmark)

    Toppari, Jorma; Juul, Anders

    2010-01-01

    Secular trends in timing of puberty appear to continue although under-nutrition has not been any longer a limiting factor for pubertal development. Now obesity and other environmental reasons have been suspected to cause this trend, and endocrine disrupting chemicals have become into focus...... as possible contributors. Epidemiological studies on endocrine disrupters are still scarce and show only weak associations between exposures and timing of puberty. Since genetic background explains 50-80% of variability in the timing of puberty, it is not surprising that the observed environmental effects...... are rather modest when individual exposures are assessed. Despite that, some exposures have been reported to be associated to early (e.g., polybrominated biphenyls) or delayed (e.g., lead) puberty. Here we shortly review the available data on recent trends in timing of puberty and the possible role...

  12. Time trends in biological fertility in Western Europe

    DEFF Research Database (Denmark)

    Joffe, Michael; Holmes, Jane; Jensen, Tina Kold;

    2013-01-01

    analyses demonstrated that this rise was visible as a male cohort effect for both TTP and contraceptive failure. On the other hand, the female birth cohort effect showed a slight fall in the first half of the study period for both TTP and contraceptive failure. As a period effect, fertility remained...... generally stable, the slight trends in TTP and contraceptive failure being in opposite directions, likely indicating an artifact. The rising trend accords with most previous evidence. The increasing trend in male fertility does not contradict the previously reported semen quality deterioration, the effects......We investigated trends in biological fertility in a comprehensive analysis of 5 major European data sets with data on time to pregnancy (TTP) and proportion of contraceptive failures. In particular, we distinguished a period effect from a birth cohort effect (lifelong tendency) in both sexes...

  13. United States Forest Disturbance Trends Observed Using Landsat Time Series

    Science.gov (United States)

    Masek, Jeffrey G.; Goward, Samuel N.; Kennedy, Robert E.; Cohen, Warren B.; Moisen, Gretchen G.; Schleeweis, Karen; Huang, Chengquan

    2013-01-01

    Disturbance events strongly affect the composition, structure, and function of forest ecosystems; however, existing U.S. land management inventories were not designed to monitor disturbance. To begin addressing this gap, the North American Forest Dynamics (NAFD) project has examined a geographic sample of 50 Landsat satellite image time series to assess trends in forest disturbance across the conterminous United States for 1985-2005. The geographic sample design used a probability-based scheme to encompass major forest types and maximize geographic dispersion. For each sample location disturbance was identified in the Landsat series using the Vegetation Change Tracker (VCT) algorithm. The NAFD analysis indicates that, on average, 2.77 Mha/yr of forests were disturbed annually, representing 1.09%/yr of US forestland. These satellite-based national disturbance rates estimates tend to be lower than those derived from land management inventories, reflecting both methodological and definitional differences. In particular the VCT approach used with a biennial time step has limited sensitivity to low-intensity disturbances. Unlike prior satellite studies, our biennial forest disturbance rates vary by nearly a factor of two between high and low years. High western US disturbance rates were associated with active fire years and insect activity, while variability in the east is more strongly related to harvest rates in managed forests. We note that generating a geographic sample based on representing forest type and variability may be problematic since the spatial pattern of disturbance does not necessarily correlate with forest type. We also find that the prevalence of diffuse, non-stand clearing disturbance in US forests makes the application of a biennial geographic sample problematic. Future satellite-based studies of disturbance at regional and national scales should focus on wall-to-wall analyses with annual time step for improved accuracy.

  14. Analysis of the Time Trends of Precipitation over Mediterranean Region

    Directory of Open Access Journals (Sweden)

    Mourad Lazri

    2014-08-01

    Full Text Available Time trends of precipitation in the north of Algeria from meteorological radar are analysed. A probabilistic approach presented here proposes to study the evolution of the rainfall phenomenon in two distinct study areas, one located in sea and other located in ground. A decision criterion is established and based on radar reflectivity in order to classify the precipitation events located in both areas. At each radar observation, a state of precipitation is classified, either convective (heavy precipitation or stratiform (average precipitation both for the "sea" and for the "ground". In all, a time series of precipitation composed of three states; no raining, stratiform precipitation and convective precipitation, is obtained for each of the two areas. Thereby, we studied and characterized the behavior of precipitation in time by a Markov chain of order one with three states. Transition probabilities are calculated. The results show that rainfall is well described by a Markov chain of order one with three states. Indeed, the stationary probabilities, which are calculated by using the Markovian model, and the actual probabilities are almost identical.

  15. 多时间序列关联规则分析的论坛舆情趋势预测%Forum Sentiment Trend Prediction Based on Multi Time Series Association Rule Analysis

    Institute of Scientific and Technical Information of China (English)

    钱爱玲; 瞿彬彬; 卢炎生; 陈攀攀; 陈国栋

    2012-01-01

    为了预测论坛舆情及其动态演变趋势,基于多时间序列的关联分析,集中分析了论坛中3个量的时间序列之间的关联规则:活跃者之间的关系强度的时间序列、坚定支持者人数的时间序列以及坚定支持者成员的变化频度的时间序列.然后给出了一种新的基于多时间序列关联分析的论坛舆情预测算法(Forum sentiment trend prediction based on multi time series association rule analysis,TPMTSA),并在真实数据集和拟合数据集上进行了大量的实验.结果表明:TPMTSA算法具有有效性和较高的运行效率.研究结果可用于论坛舆情预警监控.%In order to predict the evolving trend of forum sentiment, based on the association analysis of multi time series, the association rules of three-quantity time series over forum sentiment are anlyzed, namely, the strength of relationship between actors, the number of pillars, and the changing frequency of pillars. Then a novel prediction algorithm, forum sentiment trend prediction based on multi time series association rule analysis (TPMTSA), is proposed. Extensive experiments over real and synthetic datasets are conducted. Results show the effectiveness and the efficiency of TPMTSA. The research results can be used to monitor the forum opinion.

  16. A school based study of time trends in food habits and their relation to socio-economic status among Norwegian adolescents, 2001–2009

    OpenAIRE

    Fismen, Anne-Siri; Smith, Robert; Torsheim, Torbjørn; Samdal, Oddrun

    2014-01-01

    Background: In recent years, adolescents’ food habits have become a major source of concern, and substantial policy and intervention efforts have been made to influence adolescents to consume more fruit and vegetables and less sweets and soft drink. Particular attention has been devoted to the social gradient in food habits, aiming to reduce dietary inequality. However, few internationally published studies have evaluated trends in teenagers’ food habits, or investigated how dieta...

  17. Ground-based observations of Saturn's auroral ionosphere over three days: Trends in H3+ temperature, density and emission with Saturn local time and planetary period oscillation

    Science.gov (United States)

    O'Donoghue, James; Melin, Henrik; Stallard, Tom S.; Provan, G.; Moore, Luke; Badman, Sarah V.; Cowley, Stan W. H.; Baines, Kevin H.; Miller, Steve; Blake, James S. D.

    2016-01-01

    On 19-21 April 2013, the ground-based 10-m W.M. Keck II telescope was used to simultaneously measure H3+ emissions from four regions of Saturn's auroral ionosphere: (1) the northern noon region of the main auroral oval; (2) the northern midnight main oval; (3) the northern polar cap and (4) the southern noon main oval. The H3+ emission from these regions was captured in the form of high resolution spectral images as the planet rotated. The results herein contain twenty-three H3+ temperatures, column densities and total emissions located in the aforementioned regions - ninety-two data points in total, spread over timescales of both hours and days. Thermospheric temperatures in the spring-time northern main oval are found to be cooler than their autumn-time southern counterparts by tens of K, consistent with the hypothesis that the total thermospheric heating rate is inversely proportional to magnetic field strength. The main oval H3+ density and emission is lower at northern midnight than it is at noon, in agreement with a nearby peak in the electron influx in the post-dawn sector and a minimum flux at midnight. Finally, when arranging the northern main oval H3+ parameters as a function of the oscillation period seen in Saturn's magnetic field - the planetary period oscillation (PPO) phase - we see a large peak in H3+ density and emission at ∼115° northern phase, with a full-width at half-maximum (FWHM) of ∼44°. This seems to indicate that the influx of electrons associated with the PPO phase at 90° is responsible at least in part for the behavior of all H3+ parameters. A combination of the H3+ production and loss timescales and the ±10° uncertainty in the location of a given PPO phase are likely, at least in part, to be responsible for the observed peaks in H3+ density and emission occurring at a later time than the peak precipitation expected at 90° PPO phase.

  18. Examination of US puberty-timing data from 1940 to 1994 for secular trends

    DEFF Research Database (Denmark)

    Euling, Susan Y; Herman-Giddens, Marcia E; Lee, Peter A;

    2008-01-01

    different methods. As a result, conclusions from data comparisons have not been consistent. An expert panel was asked to evaluate the weight of evidence for whether the data, collected from 1940 to 1994, are sufficient to suggest or establish a secular trend in the timing of puberty markers in US boys or......, although the magnitude of change considered adverse was not assessed. The panel recommended (1) additional analyses of existing puberty-timing data to examine secular trends and trends in the temporal sequence of pubertal events; (2) the development of biomarkers for pubertal timing and methods to......Whether children, especially girls, are entering and progressing through puberty earlier today than in the mid-1900s has been debated. Secular trend analysis, based on available data, is limited by data comparability among studies in different populations, in different periods of time, and using...

  19. Large scale variability, long-term trends and extreme events in total ozone over the northern mid-latitudes based on satellite time series

    Science.gov (United States)

    Rieder, H. E.; Staehelin, J.; Maeder, J. A.; Ribatet, M.; Davison, A. C.

    2009-04-01

    Various generations of satellites (e.g. TOMS, GOME, OMI) made spatial datasets of column ozone available to the scientific community. This study has a special focus on column ozone over the northern mid-latitudes. Tools from geostatistics and extreme value theory are applied to analyze variability, long-term trends and frequency distributions of extreme events in total ozone. In a recent case study (Rieder et al., 2009) new tools from extreme value theory (Coles, 2001; Ribatet, 2007) have been applied to the world's longest total ozone record from Arosa, Switzerland (e.g. Staehelin 1998a,b), in order to describe extreme events in low and high total ozone. Within the current study this analysis is extended to satellite datasets for the northern mid-latitudes. Further special emphasis is given on patterns and spatial correlations and the influence of changes in atmospheric dynamics (e.g. tropospheric and lower stratospheric pressure systems) on column ozone. References: Coles, S.: An Introduction to Statistical Modeling of Extreme Values, Springer Series in Statistics, ISBN:1852334592, Springer, Berlin, 2001. Ribatet, M.: POT: Modelling peaks over a threshold, R News, 7, 34-36, 2007. Rieder, H.E., Staehelin, J., Maeder, J.A., Ribatet, M., Stübi, R., Weihs, P., Holawe, F., Peter, T., and Davison, A.C.: From ozone mini holes and mini highs towards extreme value theory: New insights from extreme events and non stationarity, submitted to J. Geophys. Res., 2009. Staehelin, J., Kegel, R., and Harris, N. R.: Trend analysis of the homogenized total ozone series of Arosa (Switzerland), 1929-1996, J. Geophys. Res., 103(D7), 8389-8400, doi:10.1029/97JD03650, 1998a. Staehelin, J., Renaud, A., Bader, J., McPeters, R., Viatte, P., Hoegger, B., Bugnion, V., Giroud, M., and Schill, H.: Total ozone series at Arosa (Switzerland): Homogenization and data comparison, J. Geophys. Res., 103(D5), 5827-5842, doi:10.1029/97JD02402, 1998b.

  20. Time trends of perfluorinated compounds from the sediment core of Tokyo Bay, Japan (1950s-2004)

    Energy Technology Data Exchange (ETDEWEB)

    Zushi, Yasuyuki; Tamada, Masafumi [Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan); Kanai, Yutaka [Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba 305-8567 (Japan); Masunaga, Shigeki, E-mail: masunaga@ynu.ac.j [Graduate School of Environment and Information Sciences, Yokohama National University, 79-7 Tokiwadai, Hodogaya, Yokohama 240-8501 (Japan)

    2010-03-15

    Perfluorinated compounds (PFCs) were detected in sediment core samples collected in Tokyo Bay to reveal their time trends. The core sample deposited during 1950s-2004 was divided into two- to three-year intervals and the concentrations of 24 types of PFCs were determined. Perfluorooctane sulfonate (PFOS) decreased gradually from the early 1990s and its precursor decreased rapidly in the late 1990s, whereas perfluorooctanoic acid (PFOA) increased rapidly. The observed trends were regarded as a reflection of the shift from perfluorooctyl sulfonyl fluoride (PFOSF)-based products to telomer-based products after the phaseout of PFOSF-based products in 2001. The branched isomers of perfluoroundecanoic acid (PFUnDA) and perfluorotridecanoic acid (PFTrDA) were detected in the sample with its ratio of linear-isomer/branched-isomer concentrations decreasing. In this study, we revealed that the sediment core can serve as a tool for reconstructing the past pollution trend of PFCs and can provide interesting evidence concerning their environmental dynamics and time trend. - This study reports the time trends of the concentrations of 24 species of PFCs, including FTCA, FTUCA and FOSAA, in a sediment core of Tokyo Bay, Japan.

  1. Nutrient trends through time in Sweden's Baltic Drainage Area

    Science.gov (United States)

    Fischer, I.; Destouni, G.; Prieto, C.

    2015-12-01

    Changes in climate and land-use have and will continue to modify regional hydrology, in turn impacting environmental health, agricultural productivity and water resource quality and availability. The Baltic region is an area of interest as the coast spans nine countries- serving over 100 million people. The Baltic Sea contains one of the largest human caused hypoxic dead zones due to eutrophication driven by anthropogenic excess loading of nutrients. Policies to reduce these loads include also international directives and agreements, such as the EU Water Framework Directive, adopted in 2000 to protect and improve water quality throughout the European Union, and the Baltic Sea Action Plan under the Helsinki Commission aimed specifically at reducing the nutrient loading to and mitigating the eutrophication of the Baltic Sea. In light of these policies and amidst the number of studies on the Baltic Sea we ask, using the accessible nutrient and discharge data what does nutrient loading look like today? Are the most excessive loads going down? Observed nutrient and flow time series across Sweden allow for answering these questions, by spatial and temporal trend analysis of loads from various parts of Sweden to the Baltic Sea. Analyzing these observed time series in conjunction with the ecological health status classifications of the EU Water Framework Directive, allows in particular for answering the question if the loads into the water bodies with the poorest water quality, and from those to the Baltic Sea, are improving, being maintained or deteriorating. Such insight is required to contribute to relevant and efficient water and nutrient load management. Furthermore, empirically calculating nutrient loads, rather than only modeling, reveals that the water body health classification may not reflect what water bodies actually contribute the heaviest loads to the Baltic Sea. This work also underscores the importance of comprehensive analysis of all available data from

  2. Extracting Common Time Trends from Concurrent Time Series: Maximum Autocorrelation Factors with Application to Tree Ring Time Series Data

    OpenAIRE

    Haugen, Matz A.; Rajaratnam, Bala; Switzer, Paul

    2015-01-01

    Concurrent time series commonly arise in various applications, including when monitoring the environment such as in air quality measurement networks, weather stations, oceanographic buoys, or in paleo form such as lake sediments, tree rings, ice cores, or coral isotopes, with each monitoring or sampling site providing one of the time series. The goal in such applications is to extract a common time trend or signal in the observed data. Other examples where the goal is to extract a common time...

  3. Visualizing trends and clusters in ranked time-series data

    Science.gov (United States)

    Gousie, Michael B.; Grady, John; Branagan, Melissa

    2013-12-01

    There are many systems that provide visualizations for time-oriented data. Of those, few provide the means of finding patterns in time-series data in which rankings are also important. Fewer still have the fine granularity necessary to visually follow individual data points through time. We propose the Ranking Timeline, a novel visualization method for modestly-sized multivariate data sets that include the top ten rankings over time. The system includes two main visualization components: a ranking over time and a cluster analysis. The ranking visualization, loosely based on line plots, allows the user to track individual data points so as to facilitate comparisons within a given time frame. Glyphs represent additional attributes within the framework of the overall system. The user has control over many aspects of the visualization, including viewing a subset of the data and/or focusing on a desired time frame. The cluster analysis tool shows the relative importance of individual items in conjunction with a visualization showing the connection(s) to other, similar items, while maintaining the aforementioned glyphs and user interaction. The user controls the clustering according to a similarity threshold. The system has been implemented as a Web application, and has been tested with data showing the top ten actors/actresses from 1929-2010. The experiments have revealed patterns in the data heretofore not explored.

  4. Radioactive contamination in Norwegian fish and seafood 1960-2013: time trends and geographical trends

    International Nuclear Information System (INIS)

    Norwegian marine waters are home to some of the world's richest fishing grounds. In 2011, Norway was the world's twelfth largest fishery nation, and the world's second largest exporter of seafood. Knowledge and documentation of the levels of radioactive contamination in fish and seafood is therefore of major importance to Norwegian consumers and the fishery industry. Monitoring of radioactive pollution in Norwegian fish and seafood has been ongoing in various ways since the early 1960's. During the 1960's, different species of fish from the Barents Sea were analysed for 'total mean beta activity minus potassium-40 (40K)'. Although not directly comparable to current measurements, these were probably the highest observed concentrations in fish during the whole monitoring period. Contamination levels decreased substantially during the late 1960's as a result of the decrease in global fallout, biological elimination of the radioactive elements and the short physical half-lives of some beta-emitters. Monitoring was more or less terminated in the following years, and little data exists from the 1970's and early 1980's, though monitoring was resumed following the Chernobyl accident in 1986. Today, different species of commercially important fish and crustacean species (as well as other species), are sampled on a regular basis from the Barents Sea, the Norwegian Sea, the North Sea and Norwegian fjords. The samples are analysed mainly for cesium-137 (137Cs) and, additionally, a selection of the samples are analysed for technetium-99 (99Tc), plutonium-239,240 (239,240Pu) and polonium-210 (210Po). This study summarizes results from the monitoring during the period 1960 to 2013. Activity concentrations of 137Cs in fish and seafood from Norwegian marine waters have been generally low during the past 20 to 25 years (up to 0.15 Bq kg-1(fresh weight) in different species of fish in the Barents Sea in 2012). However, time trends and geographical trends are clearly evident in the

  5. Radioactive contamination in Norwegian fish and seafood 1960-2013: time trends and geographical trends

    Energy Technology Data Exchange (ETDEWEB)

    Heldal, Hilde Elise; Svaeren, Ingrid; Liebig, Penny Lee [Institute of Marine Research, P. O. Box 1870 Nordnes, N-5817 Bergen (Norway); Brungot, Anne Lene; Gaefvert, Torbjoern; Rudjord, Anne Liv [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Gwynn, Justin [Norwegian Radiation Protection Authority, The Fram Centre, N-9296 Tromsoe (Norway)

    2014-07-01

    Barents Sea in 2012). However, time trends and geographical trends are clearly evident in the datasets. For example, the impact of fallout from the Chernobyl accident could be observed, particularly in samples collected in coastal areas and the Kattegat/Skagerrak and the North Sea. In recent decades there has been a slow decrease in the activity concentrations of most anthropogenic radionuclides in fish and seafood as a result of decreasing discharges from European reprocessing plants for spent nuclear fuel and the reduced impact of fallout from the Chernobyl accident. In the case of {sup 99}Tc however, activity concentrations in seawater and certain biota increased to peak values around 2000 as a result of increased discharges from Sellafield (UK) in the 1990's. In open sea areas, the activity concentrations of {sup 137}Cs in fish and seafood have been highest in the Skagerrak and the North Sea due to the proximity to the reprocessing plants at Sellafield and Cap la Hague (France) and outflowing Chernobyl-contaminated seawater from the Baltic Sea. Activity concentrations of {sup 137}Cs in fish and seafood collected in fjords in mid-Norway are up to an order of magnitude higher than in the open sea areas due to terrestrial run-off from Chernobyl fallout in Norway. (authors)

  6. HESS Opinions "More efforts and scientific rigour are needed to attribute trends in flood time series"

    Directory of Open Access Journals (Sweden)

    Y. Hundecha

    2012-05-01

    Full Text Available The question whether the magnitude and frequency of floods have changed due to climate change or other drivers of change is of high interest. The number of flood trend studies is rapidly rising. When changes are detected, many studies link the identified change to the underlying causes, i.e. they attribute the changes in flood behaviour to certain drivers of change. We propose a hypothesis testing framework for trend attribution which consists of essential ingredients for a sound attribution: evidence of consistency, evidence of inconsistency, and provision of confidence statement. Further, we evaluate the current state-of-the-art of flood trend attribution. We assess how selected recent studies approach the attribution problem, and to which extent their attribution statements seem defendable. In our opinion, the current state of flood trend attribution is poor. Attribution statements are mostly based on qualitative reasoning or even speculation. Typically, the focus of flood trend studies is the detection of change, i.e. the statistical analysis of time series, and attribution is regarded as an appendix: (1 flood time series are analysed by means of trend tests, (2 if a significant change is detected, a hypothesis on the cause of change is given, and (3 explanations or published studies are sought which support the hypothesis. We believe that we need a change in perspective and more scientific rigour: detection should be seen as an integral part of the more challenging attribution problem, and detection and attribution should be placed in a sound hypothesis testing framework.

  7. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    Science.gov (United States)

    Aksoy, H.; Unal, N. E.; Eris, E.; Yuce, M. I.

    2013-06-01

    In the 1990s, water level in the closed-basin Lake Van located in the Eastern Anatolia, Turkey, has risen up about 2 m. Analysis of the hydrometeorological data shows that change in the water level is related to the water budget of the lake. In this study, stochastic models are proposed for simulating monthly water level data. Two models considering mono- and multiple-trend time series are developed. The models are derived after removal of trend and periodicity in the dataset. Trend observed in the lake water level time series is fitted by mono- and multiple-trend lines. In the so-called mono-trend model, the time series is treated as a whole under the hypothesis that the lake water level has an increasing trend. In the second model (so-called multiple-trend), the time series is divided into a number of segments to each a linear trend can be fitted separately. Application on the lake water level data shows that four segments, each fitted with a trend line, are meaningful. Both the mono- and multiple-trend models are used for simulation of synthetic lake water level time series under the hypothesis that the observed mono- and multiple-trend structure of the lake water level persist during the simulation period. The multiple-trend model is found better for planning the future infrastructural projects in surrounding areas of the lake as it generates higher maxima for the simulated lake water level.

  8. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    Directory of Open Access Journals (Sweden)

    H. Aksoy

    2013-06-01

    Full Text Available In the 1990s, water level in the closed-basin Lake Van located in the Eastern Anatolia, Turkey, has risen up about 2 m. Analysis of the hydrometeorological data shows that change in the water level is related to the water budget of the lake. In this study, stochastic models are proposed for simulating monthly water level data. Two models considering mono- and multiple-trend time series are developed. The models are derived after removal of trend and periodicity in the dataset. Trend observed in the lake water level time series is fitted by mono- and multiple-trend lines. In the so-called mono-trend model, the time series is treated as a whole under the hypothesis that the lake water level has an increasing trend. In the second model (so-called multiple-trend, the time series is divided into a number of segments to each a linear trend can be fitted separately. Application on the lake water level data shows that four segments, each fitted with a trend line, are meaningful. Both the mono- and multiple-trend models are used for simulation of synthetic lake water level time series under the hypothesis that the observed mono- and multiple-trend structure of the lake water level persist during the simulation period. The multiple-trend model is found better for planning the future infrastructural projects in surrounding areas of the lake as it generates higher maxima for the simulated lake water level.

  9. Space-time Trends in U.S. Meteorological Droughts

    CERN Document Server

    Ganguli, Poulomi

    2015-01-01

    Understanding droughts in a climate context remains a major challenge. Over the United States, different choices of observations and metrics have often produced diametrically opposite insights. This paper focuses on understanding and characterizing meteorological droughts from station measurements of precipitation. The Standardized Precipitation Index is computed and analyzed to obtain drought severity, duration and frequency. Average drought severity trends are found to be uncertain and data-dependent. Furthermore, the mean and spatial variance do not show any discernible non-stationary behavior. However, the spatial coverage of extreme meteorological droughts in the United States exhibits an increasing trend over nearly all of the last century. Furthermore, the coverage over the last half decade exceeds that of the dust bowl era. Previous literature suggests that climate extremes do not necessarily follow the trends or uncertainties exhibited by the averages. While this possibility has been suggested for dr...

  10. Time trends in physical activity in leisure time in the Danish population from 1987 to 2005

    DEFF Research Database (Denmark)

    Petersen, Christina Bjørk; Thygesen, Lau Caspar; Helge, Jørn Wulff;

    2010-01-01

    .05). CONCLUSIONS: During the past 20 years, physical activity in leisure time has increased. Younger generations seem to be more physically active in leisure time than older generations. Due to the stable socioeconomic inequality gap in physical activity, future intervention strategies should target these......-time physical activity (dichotomised into high versus low) and temporal changes according to year of birth, age, and calendar-year were estimated in an age-period-cohort logistic regression model. Time trends in socioeconomic differences in physical activity were analysed by testing interaction terms. RESULTS......: The odds ratio (OR) of being highly physically active in leisure time in 2005 compared to 1987 was 1.6 (95% CI: 1.3-1.9) among men and 1.8 (95% CI: 1.5-2.2) among women. The age- and calendar-year-adjusted probability of being highly physically active increased with year of birth. The OR of being...

  11. Analysing time-varying trends in stratospheric ozone time series using the state space approach

    Science.gov (United States)

    Laine, M.; Latva-Pukkila, N.; Kyrölä, E.

    2014-09-01

    We describe a hierarchical statistical state space model for ozone profile time series. The time series are from satellite measurements by the Stratospheric Aerosol and Gas Experiment (SAGE) II and the Global Ozone Monitoring by Occultation of Stars (GOMOS) instruments spanning the years 1984-2011. Vertical ozone profiles were linearly interpolated on an altitude grid with 1 km resolution covering 20-60 km. Monthly averages were calculated for each altitude level and 10° wide latitude bins between 60° S and 60° N. In the analysis, mean densities are studied separately for the 25-35, 35-45, and 45-55 km layers. Model variables include the ozone mean level, local trend, seasonal oscillations, and proxy variables for solar activity, the Quasi-Biennial Oscillation (QBO), and the El Niño-Southern Oscillation (ENSO). This is a companion paper to tet{erkkitime}, where a piecewise linear model was used together with the same proxies as in this work (excluding ENSO). The piecewise linear trend was allowed to change at the beginning of 1997 in all latitudes and altitudes. In the modelling of the present paper such an assumption is not needed as the linear trend is allowed to change continuously at each time step. This freedom is also allowed for the seasonal oscillations whereas other regression coefficients are taken independent of time. According to our analyses, the slowly varying ozone background shows roughly three general development patterns. A continuous decay for the whole period 1984-2011 is evident in the southernmost latitude belt 50-60° S in all altitude regions and in 50-60° N in the lowest altitude region 25-35 km. A second pattern, where a recovery after an initial decay is followed by a further decay, is found at northern latitudes from the equator to 50° N in the lowest altitude region (25-35 km) and between 40° N and 60° N in the 35-45 km altitude region. Further ozone loss occurred after 2007 in these regions. Everywhere else a decay is followed

  12. Non-target time trend screening: a data reduction strategy for detecting emerging contaminants in biological samples.

    Science.gov (United States)

    Plassmann, Merle M; Tengstrand, Erik; Åberg, K Magnus; Benskin, Jonathan P

    2016-06-01

    Non-targeted mass spectrometry-based approaches for detecting novel xenobiotics in biological samples are hampered by the occurrence of naturally fluctuating endogenous substances, which are difficult to distinguish from environmental contaminants. Here, we investigate a data reduction strategy for datasets derived from a biological time series. The objective is to flag reoccurring peaks in the time series based on increasing peak intensities, thereby reducing peak lists to only those which may be associated with emerging bioaccumulative contaminants. As a result, compounds with increasing concentrations are flagged while compounds displaying random, decreasing, or steady-state time trends are removed. As an initial proof of concept, we created artificial time trends by fortifying human whole blood samples with isotopically labelled standards. Different scenarios were investigated: eight model compounds had a continuously increasing trend in the last two to nine time points, and four model compounds had a trend that reached steady state after an initial increase. Each time series was investigated at three fortification levels and one unfortified series. Following extraction, analysis by ultra performance liquid chromatography high-resolution mass spectrometry, and data processing, a total of 21,700 aligned peaks were obtained. Peaks displaying an increasing trend were filtered from randomly fluctuating peaks using time trend ratios and Spearman's rank correlation coefficients. The first approach was successful in flagging model compounds spiked at only two to three time points, while the latter approach resulted in all model compounds ranking in the top 11 % of the peak lists. Compared to initial peak lists, a combination of both approaches reduced the size of datasets by 80-85 %. Overall, non-target time trend screening represents a promising data reduction strategy for identifying emerging bioaccumulative contaminants in biological samples. Graphical abstract

  13. Non-target time trend screening: a data reduction strategy for detecting emerging contaminants in biological samples.

    Science.gov (United States)

    Plassmann, Merle M; Tengstrand, Erik; Åberg, K Magnus; Benskin, Jonathan P

    2016-06-01

    Non-targeted mass spectrometry-based approaches for detecting novel xenobiotics in biological samples are hampered by the occurrence of naturally fluctuating endogenous substances, which are difficult to distinguish from environmental contaminants. Here, we investigate a data reduction strategy for datasets derived from a biological time series. The objective is to flag reoccurring peaks in the time series based on increasing peak intensities, thereby reducing peak lists to only those which may be associated with emerging bioaccumulative contaminants. As a result, compounds with increasing concentrations are flagged while compounds displaying random, decreasing, or steady-state time trends are removed. As an initial proof of concept, we created artificial time trends by fortifying human whole blood samples with isotopically labelled standards. Different scenarios were investigated: eight model compounds had a continuously increasing trend in the last two to nine time points, and four model compounds had a trend that reached steady state after an initial increase. Each time series was investigated at three fortification levels and one unfortified series. Following extraction, analysis by ultra performance liquid chromatography high-resolution mass spectrometry, and data processing, a total of 21,700 aligned peaks were obtained. Peaks displaying an increasing trend were filtered from randomly fluctuating peaks using time trend ratios and Spearman's rank correlation coefficients. The first approach was successful in flagging model compounds spiked at only two to three time points, while the latter approach resulted in all model compounds ranking in the top 11 % of the peak lists. Compared to initial peak lists, a combination of both approaches reduced the size of datasets by 80-85 %. Overall, non-target time trend screening represents a promising data reduction strategy for identifying emerging bioaccumulative contaminants in biological samples. Graphical abstract

  14. Trends in timing and magnitude of flow in the Upper Indus Basin

    OpenAIRE

    M. Sharif; Archer, D.R.; Fowler, H J; N. Forsythe

    2012-01-01

    River flow is a reflection of the input of moisture and its transformation in storage and transmission over the catchment. In the Upper Indus Basin (UIB), since high altitude climate measurement and observations of glacier mass balance are weak or absent, analysis of trends in magnitude and timing in river flow provides a window on trends and fluctuations in climate and glacier outflow. Trend analysis is carried out using a Mann-Kendall nonparametric trend test on records extending from ...

  15. Trends in timing and magnitude of flow in the Upper Indus Basin

    OpenAIRE

    M. Sharif; Archer, D.R.; Fowler, H J; N. Forsythe

    2013-01-01

    River flow is a reflection of the input of moisture and its transformation in storage and transmission over the catchment. In the Upper Indus Basin (UIB), since high-altitude climate measurement and observations of glacier mass balance are weak or absent, analysis of trends in magnitude and timing in river flow provides a window on trends and fluctuations in climate and glacier outflow. Trend analysis is carried out using a Mann–Kendall nonparametric trend test on records ex...

  16. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    Directory of Open Access Journals (Sweden)

    H. Aksoy

    2013-02-01

    Full Text Available In 1990s, water level in the closed-basin Lake Van located in the Eastern Anatolia, Turkey has risen up about 2 m. Analysis of the hydrometeorological shows that change in the water level is related to the water budget of the lake. In this study, a stochastic model is generated using the measured monthly water level data of the lake. The model is derived after removal of trend and periodicity in the data set. Trend observed in the lake water level time series is fitted by mono- and multiple-trend lines. For the multiple-trend, the time series is first divided into homogeneous segments by means of SEGMENTER, segmentation software. Four segments are found meaningful practically each fitted with a trend line. Two models considering mono- and multiple-trend time series are developed. The multiple-trend model is found better for planning future development in surrounding areas of the lake.

  17. Modelling trends in climatic time series using the state space approach

    Science.gov (United States)

    Laine, Marko; Kyrölä, Erkki

    2014-05-01

    A typical feature of an atmospheric time series is that they are not stationary but exhibit both slowly varying and abrupt changes in the distributional properties. These are caused by external forcing such as changes in the solar activity or volcanic eruptions. Further, the data sampling is often nonuniform, there are data gaps, and the uncertainty of the observations can vary. When observations are combined from various sources there will be instrument and retrieval method related biases. The differences in sampling lead to uncertainties, also. Dynamic regression with state space representation of the underlying processes provides flexible tools for these challenges in the analysis. By explicitly allowing for variability in the regression coefficients we let the system properties change in time. This change in time can be modelled and estimated, also. Furthermore, the use of unobservable state variables allows modelling of the processes that are driving the observed variability, such as seasonality or external forcing, and we can explicitly allow for some modelling error. The state space approach provides a well-defined hierarchical statistical model for assessing trends defined as long term background changes in the time series. The modelling assumptions can be evaluated and the method provides realistic uncertainty estimates for the model based statements on the quantities of interest. We show that a linear dynamic model (DLM) provides very flexible tool for trend and change point analysis in time series. Given the structural parameters of the model, the Kalman filter and Kalman smoother formulas can be used to estimate the model states. Further, we provide an efficient way to account for the structural parameter uncertainty by using adaptive Markov chain Monte Carlo (MCMC) algorithm. Then, the trend related statistics can be estimated by simulating realizations of the estimated processes with fully quantified uncertainties. This presentation will provide a

  18. Trends in floods in West Africa: analysis based on 11 catchments in the region

    Science.gov (United States)

    Nka, B. N.; Oudin, L.; Karambiri, H.; Paturel, J. E.; Ribstein, P.

    2015-11-01

    After the drought of the 1970s in West Africa, the variability in rainfall and land use changes mostly affected flow, and recently flooding has been said to be an increasingly common occurrence throughout the whole of West Africa. These changes have raised many questions about the impact of climate change on the flood regimes in West African countries. This paper investigates whether floods are becoming more frequent or more severe and to what extent climate patterns have been responsible for these changes. We analyzed the trends in the floods occurring in 11 catchments within West Africa's main climate zones. The methodology includes two methods for sampling flood events, namely the AM (annual maximum) method and the POT (peak over threshold), and two perspectives of analysis are presented: long-term analysis based on two long flood time series and a regional perspective involving 11 catchments with shorter series. The Mann-Kendall trend test and the Pettitt break test were used to detect nonstationarities in the time series. The trends detected in flood time series were compared to the rainfall index trends and vegetation indices using contingency tables in order to identify the main driver of change in flood magnitude and flood frequency. The relation between the flood index and the physiographic index was evaluated through a success criterion and the Cramer criterion calculated from the contingency tables. The results show the existence of trends in flood magnitude and flood frequency time series, with two main patterns. Sahelian floods show increasing flood trends and one Sudanian. catchment presents decreasing flood trends. For the overall catchments studied, trends in the maximum 5-day consecutive rainfall index (R5d) show good coherence with trends in flood, while the trends in normalized difference vegetation indices (NDVIs) do not show a significant agreement with flood trends, meaning that this index has possibly no impact on the behavior of floods in

  19. Application of the Trend Filtering Algorithm for Photometric Time Series Data

    CERN Document Server

    Gopalan, Giri; van Eyken, Julian; Ciardi, David; von Braun, Kaspar; Kane, Stephen R

    2016-01-01

    Detecting transient light curves (e.g., transiting planets) requires high precision data, and thus it is important to effectively filter systematic trends affecting ground based wide field surveys. We apply an implementation of the Trend Filtering Algorithm (TFA) (Kovacs et al. 2005) to the 2MASS calibration catalog and select Palomar Transient Factory (PTF) photometric time series data. TFA is successful at reducing the overall dispersion of light curves, however it may over filter intrinsic variables and increase "instantaneous" dispersion when a template set is not judiciously chosen. In an attempt to rectify these issues we modify the original literature TFA by including measurement uncertainties in its computation, including ancillary data correlated with noise, and algorithmically selecting a template set using clustering algorithms as suggested by various authors. This approach may be particularly useful for appropriately accounting for variable photometric precision surveys and/or combined data-sets. ...

  20. Current trends in ground based solar magnetometry

    Science.gov (United States)

    Gosain, Sanjay

    2016-07-01

    Continuous observations of the sun, over more than a century, have led to several important discoveries in solar astronomy. These include the discovery of the solar magnetism and its cyclic modulation, active region formation and decay and their role in energetic phenomena such as fares and coronal mass ejections (CMEs), fine structure and dynamics of the sunspots and small-scale organization of the magnetic flux in the form of flux tubes and so forth. In this article we give a brief overview of advancements in solar observational techniques in recent decades and the results obtained from the such observations. These include techniques to achieve high angular resolution, high spectral and polarimetric sensitivity and innovative new detectors. A wide range of spatial, temporal and spectral domains exploited by solar astronomers to understand the solar phenomena are discussed. Many new upcoming telescopes and instruments that are designed to address different aspects of solar physics problems are briefly described. Finally, we discuss the advantages of observing from the ground and how they can complement space-based observations.

  1. Osteoporosis-Related Mortality: Time-Trends and Predictive Factors

    Directory of Open Access Journals (Sweden)

    Nelly Ziadé

    2014-07-01

    Full Text Available Osteoporosis is one of the leading causes of handicap worldwide and a major contributor to the global burden of diseases. In particular, osteoporosis is associated with excess mortality. We reviewed the impact of osteoporosis on mortality in a population by defining three categories: mortality following hip fractures, mortality following other sites of fractures, and mortality associated with low bone mineral density (BMD. Hip fractures, as well as other fractures at major sites are all associated with excess mortality, except at the forearm site. This excess mortality is higher during the first 3-6 months after the fracture and then declines over time, but remains higher than the mortality of the normal population up to 22 years after the fracture. Low BMD is also associated with high mortality, with hazard ratios of around 1.3 for every decrease in 1 standard deviation of bone density at 5 years, independently of fractures, reflecting a more fragile population. Finally predictors of mortality were identified and categorised in demographic known factors (age and male gender and in factors reflecting a poor general health status such as the number of comorbidities, low mental status, or level of social dependence. Our results indicate that the management of a patient with osteoporosis should include a multivariate approach that could be based on predictive models in the future.

  2. Time trends of mercury in feathers of West Greenland birds of prey during 1851-2003

    DEFF Research Database (Denmark)

    Dietz, Rune; Riget, Frank Farsø; Boertmann, David;

    2006-01-01

    Temporal trends of mercury (Hg) in West Greenland gyrfalcons, peregrine falcons, and white-tailed eagles were determined over 150 years from 1851 to 2003. Hg was measured in the fifth primary feather. Results showed that Hg increased in the order gyrfalcon (lowest)intermediate......) account in the temporal trend analysis. Of eight time trend analyses (three species and three age groups of which one was missing), seven showed an increase in primary feather concentrations. Of these...

  3. Time Series Analysis of Insar Data: Methods and Trends

    Science.gov (United States)

    Osmanoglu, Batuhan; Sunar, Filiz; Wdowinski, Shimon; Cano-Cabral, Enrique

    2015-01-01

    Time series analysis of InSAR data has emerged as an important tool for monitoring and measuring the displacement of the Earth's surface. Changes in the Earth's surface can result from a wide range of phenomena such as earthquakes, volcanoes, landslides, variations in ground water levels, and changes in wetland water levels. Time series analysis is applied to interferometric phase measurements, which wrap around when the observed motion is larger than one-half of the radar wavelength. Thus, the spatio-temporal ''unwrapping" of phase observations is necessary to obtain physically meaningful results. Several different algorithms have been developed for time series analysis of InSAR data to solve for this ambiguity. These algorithms may employ different models for time series analysis, but they all generate a first-order deformation rate, which can be compared to each other. However, there is no single algorithm that can provide optimal results in all cases. Since time series analyses of InSAR data are used in a variety of applications with different characteristics, each algorithm possesses inherently unique strengths and weaknesses. In this review article, following a brief overview of InSAR technology, we discuss several algorithms developed for time series analysis of InSAR data using an example set of results for measuring subsidence rates in Mexico City.

  4. Composite total solar irradiance time series show a secular 0.04 %/decade trend

    Science.gov (United States)

    Willson, R. C.; Mordvinov, A. V.

    2003-12-01

    The satellite total solar irradiance (TSI) observational database extends over the past 25 years with useful precision for solar physics and climatology investigations. Willson & Mordvinov (2003) reconciled the published results from various experiments to a common scale using overlapping comparisons to produce a composite TSI time series with sufficient precision to resolve a TSI trend of + 0.04 %/decade between successive solar activity minima. Key to this process is determining the relationship of the results of the non-overlapping ACRIM1 and ACRIM2 experiments. Two overlapping sets of results are available for this purpose: Nimbus7/ERB and the ERBS/ERBE. The ACRIM composite approach, using unaltered results published by the science teams of each experiment demonstrates a + 0.04 %/decade trend between the solar minima of 1986 and 1996 using the more precise Nimbus7/ERB data to relate ACRIM1 & 2 results. The use of ERBS/ERBE results instead produces a negligibly small trend. This is shown to be the effect of uncorrected ERBS/ERBE degradation during the 2 year ACRIM gap whose magnitude and direction account for the trend difference precisely. A further illustration of this difference is the PMOD composite TSI model of Frohlich & Lean (1998) which uses ERBS/ERBE results to relate ACRIM1 and ACRIM2. It differs from the ACRIM composite in two significant respects: a negligible trend between solar minima and lower TSI at solar maxima. Our findings indicate PMOD's lower trend and lower TSI during solar cycles 22 and 23 maxima result from their use of the ERBS/ERBE data and are therefore artifacts of its uncorrected degradation. Lower PMOD TSI during the maximum of cycle 21 is the result of the modifications of published Nimbus7/ERB and ACRIM1 data made to produce better agreement with a TSI solar proxy regression model. These modifications are not based on reevaluation of basic experiment data or algorithms and are therefore less likely to be correct than the analyses

  5. Current and Future Trends in Game-Based Learning

    Directory of Open Access Journals (Sweden)

    Carlos Vaz de Carvalho

    2014-05-01

    Full Text Available The first number of the second volume of the EAI Transactions on Serious Games focuses on the results presented on the European Conference on Game-Based Learning. This event, already on the 8th edition, has set standards in terms of presentation of research and practice and in the pointing out of new and future trends in the development of Game-Based Learning. As such, we are quite thrilled to be able to report them here.

  6. Space-Time-Isotopic Trends of Snake River Plain Basalts

    Science.gov (United States)

    Jean, M. M.; Hanan, B. B.; Shervais, J. W.

    2010-12-01

    plain high-K lavas ranges to > 99%, higher than low-K thoileiites (97-99%) from the same region. This trend is controlled by ancient cratonic lithosphere like that of the Wyoming province. This province superimposes its inherent isotopic composition on sublithospheric plume and/or asthenospheric melts. Seismic tomography and upper mantle velocity variations coupled with these results demonstrate that the sub-continental lithospheric mantle was thermally eroded and removed after this area passed over the Yellowstone plume (e.g. Humphreys and co-workers). Removal of the SCLM apparently allowed upwelling and decompression melting of residual plume material occupying the eroded plume channel. This resulted in a mantle source where the plume:SCLM ratio was greater for high-K basalts, than the low-K tholeiite source. The change in mantle source regions could have happened in as little as 200,000 years (e.g., Vetter and Shervais, 2009).

  7. A TREND DISPLACEMENT ANALYSIS FOR SPACE AND TIME ON XINTAN LANDSLIDE

    Institute of Scientific and Technical Information of China (English)

    贺可强

    1998-01-01

    This paper, having made systematic trend analysis on the front and rear segments ofXintan landslide for space and time respectively by using mathematical statistical principles,discovered that there is obvious trend displacement of the monitoring points in the rear marginarea of the slope and the rates of trend displacement gradually increase with time whereas thereis no trend displacement of the monitoring points in the front margin area. This result suggests thatthe rear margin area of segment is an area of overall sliding and is transforming towardsde.stabilization, whereas the front margin area is an area of relative stability. This analyticalresult well coincides with the conclusion of evaluation on dynamic stability. The analytical resultmentioned above shows that the medium to short term forecast and prediction of slope stabilitycan be made by using trend displacement analysis technique in order to achieve the goal of timelyevaluation and prevention.

  8. Fuzzy forecasting based on fuzzy-trend logical relationship groups.

    Science.gov (United States)

    Chen, Shyi-Ming; Wang, Nai-Yi

    2010-10-01

    In this paper, we present a new method to predict the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) based on fuzzy-trend logical relationship groups (FTLRGs). The proposed method divides fuzzy logical relationships into FTLRGs based on the trend of adjacent fuzzy sets appearing in the antecedents of fuzzy logical relationships. First, we apply an automatic clustering algorithm to cluster the historical data into intervals of different lengths. Then, we define fuzzy sets based on these intervals of different lengths. Then, the historical data are fuzzified into fuzzy sets to derive fuzzy logical relationships. Then, we divide the fuzzy logical relationships into FTLRGs for forecasting the TAIEX. Moreover, we also apply the proposed method to forecast the enrollments and the inventory demand, respectively. The experimental results show that the proposed method gets higher average forecasting accuracy rates than the existing methods.

  9. Linkwater catchment groundwater residence time, flow pattern, and hydrochemistry trends

    International Nuclear Information System (INIS)

    Water demand in the Marlborough Sounds Linkwater catchment is increasing due to pasture irrigation by dairy farmers. Little is known about the geology and the hydrology of the area. Resource management decisions are being made without a sound understanding of sustainable limits. Groundwater is the main potential source for irrigation water at Linkwater. Marlborough District Council requires a baseline hydrological assessment of the flow characteristics of the Linkwater catchment to guide day-to-day allocation practice and advice to Council. While this may be regarded as a baseline study, according to Marlborough District Council consent records, a significant amount of water (around 10,000 m3/day) has already been allocated at Linkwater. It is assumed that Linkwater catchment water is derived predominantly from local rainfall, either directly onto the flats or as surface run-off from the adjacent ranges via Cullens Creek and other smaller creeks. The variation in well depth at Linkwater suggests that there are different water-bearing formations, ranging from shallow flow through the alluvial gravels recharged by seepage from Cullens Creek or recent rainfall, to medium and deep aquifers that may contain older water. The objective of this study is to establish the hydrogeology of the Linkwater area, and groundwater flow patterns from the isotopic and chemical signature of the water, including the sources of catchment recharge and mean residence times of the water in the catchment. Tritium, chloroflurocarbons (CFCs) and sulphur hexafluoride (SF6) are used for age dating, and δ18O, N2, Ar, CH4 and a full chemical assessment at all sites (including arsenic, nutrients and heavy metals) are used along with the age data to identify flow characteristics. (author). 26 refs., 18 figs., 5 tabs

  10. Application of the Trend Filtering Algorithm for Photometric Time Series Data

    Science.gov (United States)

    Gopalan, Giri; Plavchan, Peter; van Eyken, Julian; Ciardi, David; von Braun, Kaspar; Kane, Stephen R.

    2016-08-01

    Detecting transient light curves (e.g., transiting planets) requires high-precision data, and thus it is important to effectively filter systematic trends affecting ground-based wide-field surveys. We apply an implementation of the Trend Filtering Algorithm (TFA) to the 2MASS calibration catalog and select Palomar Transient Factory (PTF) photometric time series data. TFA is successful at reducing the overall dispersion of light curves, however, it may over-filter intrinsic variables and increase “instantaneous” dispersion when a template set is not judiciously chosen. In an attempt to rectify these issues we modify the original TFA from the literature by including measurement uncertainties in its computation, including ancillary data correlated with noise, and algorithmically selecting a template set using clustering algorithms as suggested by various authors. This approach may be particularly useful for appropriately accounting for variable photometric precision surveys and/or combined data sets. In summary, our contributions are to provide a MATLAB software implementation of TFA and a number of modifications tested on synthetics and real data, summarize the performance of TFA and various modifications on real ground-based data sets (2MASS and PTF), and assess the efficacy of TFA and modifications using synthetic light curve tests consisting of transiting and sinusoidal variables. While the transiting variables test indicates that these modifications confer no advantage to transit detection, the sinusoidal variables test indicates potential improvements in detection accuracy.

  11. 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.

  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

    2016-07-01

    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. 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

    2016-07-15

    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. PMID:27418503

  14. Current and future trends in metagenomics : Development of knowledge bases

    Science.gov (United States)

    Mori, Hiroshi; Yamada, Takuji; Kurokawa, Ken

    Microbes are essential for every part of life on Earth. Numerous microbes inhabit the biosphere, many of which are uncharacterized or uncultivable. They form a complex microbial community that deeply affects against surrounding environments. Metagenome analysis provides a radically new way of examining such complex microbial community without isolation or cultivation of individual bacterial community members. In this article, we present a brief discussion about a metagenomics and the development of knowledge bases, and also discuss about the future trends in metagenomics.

  15. FURTHER CONSIDERATIONS ON SPREADSHEET-BASED AUTOMATIC TREND LINES

    Directory of Open Access Journals (Sweden)

    DANIEL HOMOCIANU

    2015-12-01

    Full Text Available Most of the nowadays business applications working with data sets allow exports to the spreadsheet format. This fact is related to the experience of common business users with such products and to the possibility to couple what they have with something containing many models, functions and possibilities to process and represent data, by that getting something in dynamics and much more than a simple static less useful report. The purpose of Business Intelligence is to identify clusters, profiles, association rules, decision trees and many other patterns or even behaviours, but also to generate alerts for exceptions, determine trends and make predictions about the future based on historical data. In this context, the paper shows some practical results obtained after testing both the automatic creation of scatter charts and trend lines corresponding to the user’s preferences and the automatic suggesting of the most appropriate trend for the tested data mostly based on the statistical measure of how close they are to the regression function.

  16. Time trends in heavy drinking among middle-aged and older adults in Denmark

    DEFF Research Database (Denmark)

    Bjørk, Christina; Thygesen, Lau Caspar; Vinther-Larsen, Mathilde;

    2008-01-01

    BACKGROUND: Studies have indicated an increasing proportion of heavy drinking among middle-aged and older Danes. Trends in consumption are often extremely sensitive to influence from various components of the time trends but only few have explored the age, period and cohort-related influences...... that the proportion of heavy drinking women increases in younger birth cohorts. This trend is not observed for men as their drinking pattern mainly increase slightly by calendar year. CONCLUSIONS: Our Danish observations for older aged individuals correspond to the social and cultural changes in the 1960s and 1970s...

  17. Degradation trend estimation of slewing bearing based on LSSVM model

    Science.gov (United States)

    Lu, Chao; Chen, Jie; Hong, Rongjing; Feng, Yang; Li, Yuanyuan

    2016-08-01

    A novel prediction method is proposed based on least squares support vector machine (LSSVM) to estimate the slewing bearing's degradation trend with small sample data. This method chooses the vibration signal which contains rich state information as the object of the study. Principal component analysis (PCA) was applied to fuse multi-feature vectors which could reflect the health state of slewing bearing, such as root mean square, kurtosis, wavelet energy entropy, and intrinsic mode function (IMF) energy. The degradation indicator fused by PCA can reflect the degradation more comprehensively and effectively. Then the degradation trend of slewing bearing was predicted by using the LSSVM model optimized by particle swarm optimization (PSO). The proposed method was demonstrated to be more accurate and effective by the whole life experiment of slewing bearing. Therefore, it can be applied in engineering practice.

  18. Mobile eHealth interventions for obesity: a timely opportunity to leverage convergence trends.

    Science.gov (United States)

    Tufano, James T; Karras, Bryant T

    2005-12-20

    Obesity is often cited as the most prevalent chronic health condition and highest priority public health problem in the United States. There is a limited but growing body of evidence suggesting that mobile eHealth behavioral interventions, if properly designed, may be effective in promoting and sustaining successful weight loss and weight maintenance behavior changes. This paper reviews the current literature on the successes and failures of public health, provider-administered, and self-managed behavioral health interventions for weight loss. The prevailing theories of health behavior change are discussed from the perspective of how this knowledge can serve as an evidence base to inform the design of mobile eHealth weight loss interventions. Tailored informational interventions, which, in recent years, have proven to be the most effective form of conventional health behavior intervention for weight loss, are discussed. Lessons learned from the success of conventional tailored informational interventions and the early successes of desktop computer-assisted self-help weight management interventions are presented, as are design principles suggested by Social Cognitive Theory and the Social Marketing Model. Relevant computing and communications technology convergence trends are also discussed. The recent trends in rapid advancement, convergence, and public adoption of Web-enabled cellular telephone and wireless personal digital assistant (PDA) devices provide timely opportunities to deliver the mass customization capabilities, reach, and interactivity required for the development, administration, and adoption of effective population-level eHealth tailored informational interventions for obesity.

  19. Temporal correlations in population trends: Conservation implications from time-series analysis of diverse animal taxa

    OpenAIRE

    Keith, D.; Akcakaya, H. R.; Butchart, S.H.M; Collen, B.; Dulvy, N. K.; Holmes, E.E.; Hutchings, J. A.; Keinath, D.; Schwartz, M K; Shelton, A. O.; Waples, R. S.

    2015-01-01

    Population trends play a large role in species risk assessments and conservation planning, and species are often considered threatened if their recent rate of decline meets certain thresholds, regardless how large the population is. But how reliable an indicator of extinction risk is a single estimate of population trend? Given the integral role this decline-based approach has played in setting conservation priorities, it is surprising that it has undergone little empirical scrutiny. We compi...

  20. A Genetic Algorithm Optimized Decision Tree-SVM based Stock Market Trend Prediction System

    Directory of Open Access Journals (Sweden)

    Binoy B. Nair

    2010-12-01

    Full Text Available Prediction of stock market trends has been an area of great interest both to researchers attempting to uncover the information hidden in the stock market data and for those who wish to profit by trading stocks. The extremely nonlinear nature of the stock market data makes it very difficult to design a system that can predict the future direction of the stock market with sufficient accuracy. This work presents a data mining based stock market trend prediction system, which produces highly accurate stock market forecasts. The proposed system is a genetic algorithm optimized decision tree-support vector machine (SVM hybrid, which can predict one-day-ahead trends in stockmarkets. The uniqueness of the proposed system lies in the use ofthe hybrid system which can adapt itself to the changing market conditions and in the fact that while most of the attempts at stockmarket trend prediction have approached it as a regression problem, present study converts the trend prediction task into a classification problem, thus improving the prediction accuracysignificantly. Performance of the proposed hybrid system isvalidated on the historical time series data from the Bombaystock exchange sensitive index (BSE-Sensex. The system performance is then compared to that of an artificial neural network (ANN based system and a naïve Bayes based system. It is found that the trend prediction accuracy is highest for the hybrid system and the genetic algorithm optimized decision tree- SVM hybrid system outperforms both the artificial neural network and the naïve bayes based trend prediction systems.

  1. Time-space trends in cancer incidence in The Netherlands in 1989–2003

    NARCIS (Netherlands)

    Siesling, Sabine; Aa, van der Maaike A.; Coebergh, Jan W.W.; Pukkala, Eero

    2008-01-01

    Incidence of cancer may vary within a country and over time because of previous differences in exposure to risk factors or interventions for early detection (screening). This study describes time-space trends of incidence of common cancer sites across the Netherlands during the period 1989–2003 and

  2. Geographical Variations in Sex Ratio Trends over Time in Multiple Sclerosis

    NARCIS (Netherlands)

    Trojano, Maria; Lucchese, Guglielmo; Graziano, Giusi; Taylor, Bruce V.; Simpson, Steve; Lepore, Vito; Grand'Maison, Francois; Duquette, Pierre; Izquierdo, Guillermo; Grammond, Pierre; Amato, Maria Pia; Bergamaschi, Roberto; Giuliani, Giorgio; Boz, Cavit; Hupperts, Raymond; Van Pesch, Vincent; Lechner-Scott, Jeannette; Cristiano, Edgardo; Fiol, Marcela; Oreja-Guevara, Celia; Laura Saladino, Maria; Verheul, Freek; Slee, Mark; Paolicelli, Damiano; Tortorella, Carla; D'Onghia, Mariangela; Iaffaldano, Pietro; Direnzo, Vita; Butzkueven, Helmut

    2012-01-01

    Background: A female/male (F/M) ratio increase over time in multiple sclerosis (MS) patients was demonstrated in many countries around the world. So far, a direct comparison of sex ratio time-trends among MS populations from different geographical areas was not carried out. Objective: In this paper

  3. Trend analysis of rainfall time series for Sindh river basin in India

    Science.gov (United States)

    Gajbhiye, Sarita; Meshram, Chandrashekhar; Mirabbasi, Rasoul; Sharma, S. K.

    2016-08-01

    The study of precipitation trends is critically important for a country like India whose food security and economy are dependent on the timely availability of water such as 83 % water used for agriculture sector, 12 % for industry sector and only 5 % for domestic sector. In this study, the historical rainfall data for the periods 1901-2002 and 1942-2002 of the Sindh river basin, India, were analysed for monthly, seasonal and annual trends. The conventional Mann-Kendall test (MK) and Mann-Kendall test (MMK), after the removal of the effect of all significant autocorrelation coefficients, and Sen's slope estimator were used to identify the trends. Kriging technique was used for interpolating the spatial pattern using Arc GIS 9.3. The analysis suggested significant increase in the trend of rainfall for seasonal and annual series in the Sindh basin during 1901-2002.

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

    International Nuclear Information System (INIS)

    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

  5. Worldwide incidence of malaria in 2009: estimates, time trends, and a critique of methods.

    Directory of Open Access Journals (Sweden)

    Richard E Cibulskis

    2011-12-01

    Full Text Available BACKGROUND: Measuring progress towards Millennium Development Goal 6, including estimates of, and time trends in, the number of malaria cases, has relied on risk maps constructed from surveys of parasite prevalence, and on routine case reports compiled by health ministries. Here we present a critique of both methods, illustrated with national incidence estimates for 2009. METHODS AND FINDINGS: We compiled information on the number of cases reported by National Malaria Control Programs in 99 countries with ongoing malaria transmission. For 71 countries we estimated the total incidence of Plasmodium falciparum and P. vivax by adjusting the number of reported cases using data on reporting completeness, the proportion of suspects that are parasite-positive, the proportion of confirmed cases due to each Plasmodium species, and the extent to which patients use public sector health facilities. All four factors varied markedly among countries and regions. For 28 African countries with less reliable routine surveillance data, we estimated the number of cases from model-based methods that link measures of malaria transmission with case incidence. In 2009, 98% of cases were due to P. falciparum in Africa and 65% in other regions. There were an estimated 225 million malaria cases (5th-95th centiles, 146-316 million worldwide, 176 (110-248 million in the African region, and 49 (36-68 million elsewhere. Our estimates are lower than other published figures, especially survey-based estimates for non-African countries. CONCLUSIONS: Estimates of malaria incidence derived from routine surveillance data were typically lower than those derived from surveys of parasite prevalence. Carefully interpreted surveillance data can be used to monitor malaria trends in response to control efforts, and to highlight areas where malaria programs and health information systems need to be strengthened. As malaria incidence declines around the world, evaluation of control efforts

  6. Advances and trends in ionophore-based chemical sensors

    Science.gov (United States)

    Mikhelson, K. N.; Peshkova, M. A.

    2015-06-01

    The recent advances in the theory and practice of potentiometric, conductometric and optical sensors based on ionophores are critically reviewed. The role of the heterogeneity of the sensor/sample systems is emphasized, and it is shown that due to this heterogeneity such sensors respond to the analyte activities rather than to concentrations. The basics of the origin of the response of all three kinds of ionophore-based sensors are briefly described. The use of novel sensor materials, new preparation and application techniques of the sensors as well as advances in theoretical treatment of the sensor response are analyzed using literature sources published mainly from 2012 to 2014. The basic achievements made in the past are also addressed when necessary for better understanding of the trends in the field of ionophore-based sensors. The bibliography includes 295 references.

  7. Time trends in total ankle arthroplasty in the USA: a study of the National Inpatient Sample.

    Science.gov (United States)

    Singh, Jasvinder A; Ramachandran, Rekha

    2016-01-01

    The objective of this study was to assess the time trends in utilization, clinical characteristics, and outcomes of patients undergoing total ankle arthroplasty (TAA) in the USA. We used the Nationwide Inpatient Sample (NIS) data from 1998 to 2010 to examine time trends in the utilization rates of TAA. We used the Cochran Armitage test for trend to assess time trends across the years and the analysis of variance (ANOVA), Wilcoxon test, or chi-squared test (as appropriate) to compare the first (1998-2000) and the last time periods (2009-2010). TAA utilization rate increased significant from 1998 to 2010: 0.13 to 0.84 per 100,000 overall, 0.14 to 0.88 per 100,000 in females, and from 0.11 to 0.81 per 100,000 in males (p  0.05). The utilization rate of TAA increased rapidly in the USA from 1998 to 2010, but post-arthroplasty mortality rate was stable. Underlying diagnosis and medical comorbidity changed over time and both can impact outcomes after TAA. Further studies should examine how the outcomes and complications of TAA have evolved over time.

  8. Analysis of hydrological trend for radioactivity content in bore-hole water samples using wavelet based denoising

    International Nuclear Information System (INIS)

    A wavelet transform based denoising methodology has been applied to detect the presence of any discernable trend in 137Cs and 90Sr activity levels in bore-hole water samples collected four times a year over a period of eight years, from 2002 to 2009, in the vicinity of typical nuclear facilities inside the restricted access zones. The conventional non-parametric methods viz., Mann–Kendall and Spearman rho, along with linear regression when applied for detecting the linear trend in the time series data do not yield results conclusive for trend detection with a confidence of 95% for most of the samples. The stationary wavelet based hard thresholding data pruning method with Haar as the analyzing wavelet was applied to remove the noise present in the same data. Results indicate that confidence interval of the established trend has significantly improved after pre-processing to more than 98% compared to the conventional non-parametric methods when applied to direct measurements. -- Highlights: ► Environmental trend analysis with wavelet pre-processing was carried out. ► Removal of local fluctuations to obtain the trend in a time series with various mother wavelets. ► Theoretical validation of the methodology with model outputs. ► Efficient detection of trend for 137Cs, 90Sr in bore-hole water samples improves the associated confidence interval to more than 98%. ► Wavelet based pre-processing reduces the indecisive nature of the detected trend

  9. State Disparities in Time Trends of Adolescent Body Mass Index Percentile and Weight-Related Behaviors in the United States

    OpenAIRE

    Taber, Daniel R.; Stevens, June; Poole, Charles; Maciejewski, Matthew L.; Evenson, Kelly R.; Ward, Dianne S

    2012-01-01

    Evidence is conflicting as to whether youth obesity prevalence has reached a plateau in the United States overall. Trends vary by state, and experts recommend exploring whether trends in weight-related behaviors are associated with changes in weight status trends. Thus, our objective was to estimate between-state variation in time trends of adolescent body mass index (BMI) percentile and weight-related behaviors from 2001 to 2007. A time series design combined cross-sectional Youth Risk Behav...

  10. 45-Year trends in women's use of time and household management energy expenditure.

    Directory of Open Access Journals (Sweden)

    Edward Archer

    Full Text Available CONTEXT: Relationships between socio-environmental factors and obesity are poorly understood due to a dearth of longitudinal population-level research. The objective of this analysis was to examine 45-year trends in time-use, household management (HM and energy expenditure in women. DESIGN AND PARTICIPANTS: Using national time-use data from women 19-64 years of age, we quantified time allocation and household management energy expenditure (HMEE from 1965 to 2010. HM was defined as the sum of time spent in food preparation, post-meal cleaning activities (e.g., dish-washing, clothing maintenance (e.g., laundry, and general housework. HMEE was calculated using body weights from national surveys and metabolic equivalents. RESULTS: The time allocated to HM by women (19-64 yrs decreased from 25.7 hr/week in 1965 to 13.3 hr/week in 2010 (P<0.001, with non-employed women decreasing by 16.6 hr/week and employed women by 6.7 hr/week (P<0.001. HMEE for non-employed women decreased 42% from 25.1 Mj/week (6004 kilocalories per week in 1965 to 14.6 Mj/week (3486 kcal/week in 2010, a decrement of 10.5 Mj/week or 1.5 Mj/day (2518 kcal/week; 360 kcal/day (P<0.001, whereas employed women demonstrated a 30% decrement of 3.9 Mj/week, 0.55 Mj/day (923 kcal/week, 132 kcal/day (P<0.001. The time women spent in screen-based media use increased from 8.3 hr/week in 1965 to 16.5 hr/week in 2010 (P<0.001, with non-employed women increasing 9.6 hr/week and employed women 7.5 hr/week (P<0.001. CONCLUSIONS: From 1965 to 2010, there was a large and significant decrease in the time allocated to HM. By 2010, women allocated 25% more time to screen-based media use than HM (i.e., cooking, cleaning, and laundry combined. The reallocation of time from active pursuits (i.e., housework to sedentary pastimes (e.g., watching TV has important health consequences. These results suggest that the decrement in HMEE may have contributed to the increasing prevalence of obesity in women during

  11. Trend analysis of the 20 years time series of stratospheric ozone profiles observed by the GROMOS microwave radiometer at Bern

    Directory of Open Access Journals (Sweden)

    L. Moreira

    2015-06-01

    Full Text Available The ozone radiometer GROMOS (GROund-based Millimeterwave Ozone Spectrometer performs continuous observations of stratospheric ozone profiles since 1994 above Bern, Switzerland. GROMOS is part of the Network for the Detection of Atmospheric Composition Change (NDACC. From November 1994 to October 2011, the ozone line spectra were measured by a filter bench (FB. In July 2009, a Fast-Fourier-Transform spectrometer (FFTS has been added as backend to GROMOS. The new FFTS and the original FB measured in parallel for over two years. The ozone profiles retrieved separately from the ozone line spectra of FB and FFTS agree within 5 % at pressure levels from 30 to 0.5 hPa, from October 2009 to August 2011. A careful harmonisation of both time series has been carried out by taking the FFTS as the reference instrument for the FB. This enables us to assess the long-term trend derived from more than 20 years of stratospheric ozone observations at Bern. The trend analysis has been performed by using a robust multilinear parametric trend model which includes a linear term, the solar variability, the El Niño–Southern Oscillation (ENSO index, the quasi-biennial oscillation (QBO, the annual and semi-annual oscillation and several harmonics with period lengths between 3 and 24 months. Over the last years, some experimental and modelling trend studies have shown that the stratospheric ozone trend is levelling off or even turning positive. With our observed ozone profiles, we are able to support this statement by reporting a statistically significant trend of +3.14 % decade-1 at 4.36 hPa, covering the period from January 1997 to January 2015, above Bern. Additionally, we have estimated a negative trend over this period of −3.94 % decade-1 at 0.2 hPa.

  12. Preterm birth time trends in Europe: A study of 19 countries

    NARCIS (Netherlands)

    Zeitlin, J.; Szamotulska, K.; Drewniak, N.; Mohangoo, A.D.; Chalmers, J.; Sakkeus, L.; Irgens, L.; Gatt, M.; Gissler, M.; Blondel, B.

    2013-01-01

    Objective To investigate time trends in preterm birth in Europe by multiplicity, gestational age, and onset of delivery. Design Analysis of aggregate data from routine sources. Setting Nineteen European countries. Population Live births in 1996, 2000, 2004, and 2008. Methods Annual risk ratios of pr

  13. Examination of US puberty-timing data from 1940 to 1994 for secular trends

    DEFF Research Database (Denmark)

    Euling, Susan Y; Herman-Giddens, Marcia E; Lee, Peter A;

    2008-01-01

    girls. A majority of the panelists agreed that data are sufficient to suggest a trend toward an earlier breast development onset and menarche in girls but not for other female pubertal markers. A minority of panelists concluded that the current data on girls' puberty timing for any marker are...

  14. A Google Trends-based approach for monitoring NSSI

    Directory of Open Access Journals (Sweden)

    Bragazzi NL

    2013-12-01

    Full Text Available Nicola Luigi Bragazzi DINOGMI, Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, Section of Psychiatry, University of Genoa, Genoa, Italy Abstract: Non-suicidal self-injury (NSSI is an intentional, direct, and socially unacceptable behavior resulting in the destruction of one's own body tissues with no intention of dying or committing suicide, even though it is associated with a higher risk of attempted, planned, or just considered suicide. In this preliminary report, we introduce the concept of “NSSI 2.0”; that is to say, the study of the Internet usage by subjects with NSSI, and we introduce a Google Trends-based approach for monitoring NSSI, called NSSI infodemiology and infoveillance. Despite some limitations, Google Trends has already proven to be reliable for infectious diseases monitoring, and here we extend its application and potentiality in the field of suicidology. Ad hoc web portals and surveys could be designed in light of the reported results for helping people with NSSI. Keywords: infodemiology, infoveillance, Internet, non-suicidal self-injury

  15. Trends in TIMSS Responses over Time: Evidence of Global Forces in Education?

    Science.gov (United States)

    Rutkowski, Leslie; Rutkowski, David

    2009-01-01

    In this article, the influence of global processes on international mathematics curricula as evidenced by item responses to 3 Trends in International Mathematics and Science Study (TIMSS) administrations (1995, 1999, and 2003) is considered. Based on Dale's (2000) argument, we set out to test 2 plausible impacts of global processes on education.…

  16. Bayes Methods for Trending Multiple Time Series with an Empirical Application to the US Economy

    OpenAIRE

    Phillips, Peter C. B.

    1992-01-01

    Multiple time series models with stochastic regressors are considered and primary attention is given to vector autoregressions (VAR's) with trending mechanisms that may be stochastic, deterministic or both. In a Bayesian framework, the data density in such a system implies the existence of a time series "Bayes model" and "Bayes measure" of the data. These are predictive models and measures for the next period observation given the historical trajectory to the present. Issues of model selectio...

  17. Prevalence of dementia in East Asia: a synthetic review of time trends

    OpenAIRE

    Wu, Yu-Tzu; Brayne, Carol; Matthews, Fiona E.

    2015-01-01

    Objective This study aims to synthesise evidence on time trends of dementia prevalence in East Asian countries including Japan, China, South Korea and Taiwan and assess the impact of the societal changes on future prevalence. Method Relevant reviews and recent nationwide studies in East Asia were identified to investigate changes in prevalence of dementia over time taking into account the potential impact of methodological factors and study designs. Results The robust evidence that has been i...

  18. Mindfulness-based cognitive therapy for depression: trends and developments

    Directory of Open Access Journals (Sweden)

    MacKenzie MB

    2016-05-01

    Full Text Available Meagan B MacKenzie,1 Nancy L Kocovski21Department of Psychology, Ryerson University, Toronto, ON, Canada; 2Department of Psychology, Wilfrid Laurier University, Waterloo, ON, CanadaAbstract: Mindfulness-based cognitive therapy (MBCT was developed as a psychological intervention for individuals at risk of depressive relapse. Possible mechanisms of change for this intervention are in line with its theoretical underpinnings, and include increases in mindfulness and/or decreases in negative repetitive thoughts. This review provides an overview of current trends in MBCT research, including efficacy and questions regarding the specific effects of MBCT in light of recent comparisons with structurally equivalent control conditions, mechanisms of change, and moderators of treatment outcome. In addition, future directions are discussed, such as challenges with training an adequate number of therapists and disseminating this therapy.Keywords: MBCT, efficacy, mechanisms of change, dissemination, moderators

  19. A global perspective on trends in nature-based tourism.

    Science.gov (United States)

    Balmford, Andrew; Beresford, James; Green, Jonathan; Naidoo, Robin; Walpole, Matt; Manica, Andrea

    2009-06-30

    Reports of rapid growth in nature-based tourism and recreation add significant weight to the economic case for biodiversity conservation but seem to contradict widely voiced concerns that people are becoming increasingly isolated from nature. This apparent paradox has been highlighted by a recent study showing that on a per capita basis, visits to natural areas in the United States and Japan have declined over the last two decades. These results have been cited as evidence of "a fundamental and pervasive shift away from nature-based recreation"-but how widespread is this phenomenon? We address this question by looking at temporal trends in visitor numbers at 280 protected areas (PAs) from 20 countries. This more geographically representative dataset shows that while PA visitation (whether measured as total or per capita visit numbers) is indeed declining in the United States and Japan, it is generally increasing elsewhere. Total visit numbers are growing in 15 of the 20 countries for which we could get data, with the median national rate of change unrelated to the national rate of population growth but negatively associated with wealth. Reasons for this reversal of growth in the richest countries are difficult to pin down with existing data, but the pattern is mirrored by trends in international tourist arrivals as a whole and so may not necessarily be caused by disaffection with nature. Irrespective of the explanation, it is clear that despite important downturns in some countries, nature-related tourism is far from declining everywhere, and may still have considerable potential both to generate funds for conservation and to shape people's attitudes to the environment.

  20. Improving stratospheric transport trend analysis based on SF6 and CO2 measurements

    Science.gov (United States)

    Ray, Eric A.; Moore, Fred L.; Rosenlof, Karen H.; Davis, Sean M.; Sweeney, Colm; Tans, Pieter; Wang, Tao; Elkins, James W.; Bönisch, Harald; Engel, Andreas; Sugawara, Satoshi; Nakazawa, T.; Aoki, S.

    2014-12-01

    In this study we reexamine nearly four decades of in situ balloon-based stratospheric observations of SF6 and CO2 with an idealized model and reanalysis products. We use new techniques to account for the spatial and temporal inhomogeneity of the sparse balloon profiles and to calculate stratospheric mean ages of air more consistently from the observations with the idealized model. By doing so we are able to more clearly show and account for the variability of mean age of air throughout the bulk of the depth of the stratosphere. From an idealized model guided by the observations, we identify variability in the mean age due to the seasonal cycle of stratospheric transport, the quasi-biennial oscillation in tropical zonal winds, major volcanic eruptions, and linear trends that vary significantly with altitude. We calculate a negative mean age trend in the lowest 5 km of the stratosphere that agrees within uncertainties with a trend calculated from a set of chemistry climate model mean ages in this layer. The mean age trends reverse sign in the middle and upper stratosphere and are in agreement with a previous positive trend estimate using the same observational data set, although we have substantially reduced the uncertainty on the trend. Our analysis shows that a long time series of in situ profile measurements of trace gases such as SF6 and CO2 can be a unique and useful indicator of stratospheric circulation variability on a range of time scales and an important contributor to help validate the stratospheric portion of global chemistry climate models. However, with only SF6 and CO2 measurements, the competing effects on mean age between mean circulation and mixing (tropical entrainment) are not uniquely separable.

  1. Trends in Flow-based Biosensing Systems for Pesticide Assessment

    Directory of Open Access Journals (Sweden)

    Jean-Louis Marty

    2006-10-01

    Full Text Available This review gives a survey on the state of the art of pesticide detection usingflow-based biosensing systems for sample screening. Although immunosensor systems havebeen proposed as powerful pesticide monitoring tools, this review is mainly focused onenzyme-based biosensors, as they are the most commonly employed when using a flowsystem. Among the different detection methods able to be integrated into flow-injectionanalysis (FIA systems, the electrochemical ones will be treated in more detail, due to theirhigh sensitivity, simple sample pretreatment, easy operational procedures and real-timedetection. During the last decade, new trends have been emerging in order to increase theenzyme stability, the sensitivity and selectivity of the measurements, and to lower thedetection limits. These approaches are based on (i the design of novel matrices for enzymeimmobilisation, (ii new manifold configurations of the FIA system, sometimes includingminiaturisation or lab-on-chip protocols thanks to micromachining technology, (iii the useof cholinesterase enzymes either from various commercial sources or genetically modifiedwith the aim of being more sensitive, (iv the incorporation of other highly specificenzymes, such as organophosphate hydrolase (OPH or parathion hydrolase (PH and (v thecombination of different electrochemical methods of detection. This article discusses thesenovel strategies and their advantages and limitations.

  2. Mapping Mountain Pine Beetle Mortality through Growth Trend Analysis of Time-Series Landsat Data

    Directory of Open Access Journals (Sweden)

    Lu Liang

    2014-06-01

    Full Text Available Disturbances are key processes in the carbon cycle of forests and other ecosystems. In recent decades, mountain pine beetle (MPB; Dendroctonus ponderosae outbreaks have become more frequent and extensive in western North America. Remote sensing has the ability to fill the data gaps of long-term infestation monitoring, but the elimination of observational noise and attributing changes quantitatively are two main challenges in its effective application. Here, we present a forest growth trend analysis method that integrates Landsat temporal trajectories and decision tree techniques to derive annual forest disturbance maps over an 11-year period. The temporal trajectory component successfully captures the disturbance events as represented by spectral segments, whereas decision tree modeling efficiently recognizes and attributes events based upon the characteristics of the segments. Validated against a point set sampled across a gradient of MPB mortality, 86.74% to 94.00% overall accuracy was achieved with small variability in accuracy among years. In contrast, the overall accuracies of single-date classifications ranged from 37.20% to 75.20% and only become comparable with our approach when the training sample size was increased at least four-fold. This demonstrates that the advantages of this time series work flow exist in its small training sample size requirement. The easily understandable, interpretable and modifiable characteristics of our approach suggest that it could be applicable to other ecoregions.

  3. Mapping mountain pine beetle mortality through growth trend analysis of time-series landsat data

    Science.gov (United States)

    Liang, Lu; Chen, Yanlei; Hawbaker, Todd J.; Zhu, Zhi-Liang; Gong, Peng

    2014-01-01

    Disturbances are key processes in the carbon cycle of forests and other ecosystems. In recent decades, mountain pine beetle (MPB; Dendroctonus ponderosae) outbreaks have become more frequent and extensive in western North America. Remote sensing has the ability to fill the data gaps of long-term infestation monitoring, but the elimination of observational noise and attributing changes quantitatively are two main challenges in its effective application. Here, we present a forest growth trend analysis method that integrates Landsat temporal trajectories and decision tree techniques to derive annual forest disturbance maps over an 11-year period. The temporal trajectory component successfully captures the disturbance events as represented by spectral segments, whereas decision tree modeling efficiently recognizes and attributes events based upon the characteristics of the segments. Validated against a point set sampled across a gradient of MPB mortality, 86.74% to 94.00% overall accuracy was achieved with small variability in accuracy among years. In contrast, the overall accuracies of single-date classifications ranged from 37.20% to 75.20% and only become comparable with our approach when the training sample size was increased at least four-fold. This demonstrates that the advantages of this time series work flow exist in its small training sample size requirement. The easily understandable, interpretable and modifiable characteristics of our approach suggest that it could be applicable to other ecoregions.

  4. NOAA Laboratory for Satellite Altimetry Sea Level Rise Products: Global and regional sea level time series and trend maps for the major ocean basins and marginal seas, based on measurements from satellite radar altimeters, from 1992-12-17 to 2016-09-15 (NCEI Accession 0125535)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains global and regional mean sea level time series and trend maps calculated on a continual basis since December 1992 by Laboratory for...

  5. Geo-mapping of time trends in childhood caries risk--a method for assessment of preventive care

    DEFF Research Database (Denmark)

    Strömberg, Ulf; Holmn, Anders; Magnusson, Kerstin;

    2012-01-01

    Dental caries is unevenly distributed within populations with a higher burden in low socio-economy groups. Several attempts have been made to allocate resources to those that need them the most; there is a need for convenient approaches to population-based monitoring of caries risk over time....... The aim of this study was to develop the geo-map concept, addressing time trends in caries risk, and demonstrate the novel approach by analyzing epidemiological data from preschool residents in the region of Halland, Sweden....

  6. Arresting Strategy Based on Dynamic Criminal Networks Changing over Time

    Directory of Open Access Journals (Sweden)

    Junqing Yuan

    2013-01-01

    Full Text Available We investigate a sequence of dynamic criminal networks on a time series based on the dynamic network analysis (DNA. According to the change of networks’ structure, networks’ variation trend is analyzed to forecast its future structure. Finally, an optimal arresting time and priority list are designed based on our analysis. Better results can be expected than that based on social network analysis (SNA.

  7. Analysing time-varying trends in stratospheric ozone time series using the state space approach

    OpenAIRE

    M. Laine; N. Latva-Pukkila; E. Kyrölä

    2014-01-01

    We describe a hierarchical statistical state space model for ozone profile time series. The time series are from satellite measurements by the Stratospheric Aerosol and Gas Experiment (SAGE) II and the Global Ozone Monitoring by Occultation of Stars (GOMOS) instruments spanning the years 1984–2011. Vertical ozone profiles were linearly interpolated on an altitude grid with 1 km resolution covering 20–60 km. Monthly averages were calculated for each altitude level and 10° wid...

  8. Time trend by region of suicides and suicidal thoughts among Greenland Inuit

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Larsen, Christina Viskum Lytken

    2015-01-01

    and suicidal thoughts among the Inuit in Greenland. DESIGN: Data included the Greenland registry of causes of death for 1970-2011 and 2 cross-sectional health surveys carried out in 1993-1994 and 2005-2010 with 1,580 and 3,102 Inuit participants, respectively. RESULTS: Suicide rates were higher among men than......BACKGROUND: Suicides remain a major public health problem in Greenland. Their increase coincides with the modernization since 1950. Serious suicidal thoughts are reported by a significant proportion of participants in countrywide surveys. OBJECTIVE: To analyze the time trend by region of suicides...... women while the prevalence of suicidal thoughts was higher among women. Suicide rates for men and women together increased from 1960 to 1980 and have remained around 100 per 100,000 person-years since then. The regional pattern of time trend for suicide rates varied with an early peak in the capital...

  9. Time series requirements and trends of temperature and precipitation extremes over Italy

    Science.gov (United States)

    Fioravanti, Guido; Desiato, Franco; Fraschetti, Piero; Perconti, Walter; Piervitali, Emanuela

    2013-04-01

    Extreme climate events have strong impacts on society and economy; accordingly,the knowledge of their trends on long period is crucial for the definition and implementation of a national adaptation strategy to climate change. The Research Programme on Climate Variability and Predictability (CLIVAR) identified a set of temperature and precipitation indices suited to investigate variability and trends of climate extremes. It is well known that extreme indices calculation is more demanding than first and second order statistics are: daily temperature and precipitation data are required and strict constrains in terms of continuity and completeness must be met. In addition, possible dishomogeneities affecting time series must be identified and adjusted before indices calculation. When metadata are not available, statistical methods can provide scientist a relevant support for homogeneity check; however, ad-hoc decision criteria (sometimes subjective) must be applied whenever contradictory results characterize different statistical homogeneity tests. In this work, a set of daily (minimum and maximum) temperature and precipitation time series for the period 1961-2011 were selected in order to guarantee a quite uniform spatial distribution of the stations over the Italian territory and according to the afore-said continuity and completeness criteria. Following the method described by Vincent, the homogeneity check of temperature time series was run at annual level. Two well-documented tests were employed (F-test and T-test), both implemented in the free R-package RHtestV3. The Vincent method was also used for a further investigation of time series homogeneity. Temperature dishomogeneous series were discarded. For precipitation series, no homogeneity check was run. The selected series were employed at daily level to calculate a reliable set of extreme indices. For each station, a linear model was employed for indices trend estimation. Finally, single station results were

  10. Evaluation of tropospheric and stratospheric ozone trends over Western Europe from ground-based FTIR network observations

    Directory of Open Access Journals (Sweden)

    C. Vigouroux

    2008-12-01

    Full Text Available Within the European project UFTIR (Time series of Upper Free Troposphere observations from an European ground-based FTIR network, six ground-based stations in Western Europe, from 79° N to 28° N, all equipped with Fourier Transform infrared (FTIR instruments and part of the Network for the Detection of Atmospheric Composition Change (NDACC, have joined their efforts to evaluate the trends of several direct and indirect greenhouse gases over the period 1995–2004. The retrievals of CO, CH4, C2H6, N2O, CHClF2, and O3 have been optimized. Using the optimal estimation method, some vertical information can be obtained in addition to total column amounts. A bootstrap resampling method has been implemented to determine annual partial and total column trends for the target gases. The present work focuses on the ozone results. The retrieved time series of partial and total ozone columns are validated with ground-based correlative data (Brewer, Dobson, UV-Vis, ozonesondes, and Lidar. The observed total column ozone trends are in agreement with previous studies: 1 no total column ozone trend is seen at the lowest latitude station Izaña (28° N; 2 slightly positive total column trends are seen at the two mid-latitude stations Zugspitze and Jungfraujoch (47° N, only one of them being significant; 3 the highest latitude stations Harestua (60° N, Kiruna (68° N and Ny-Ålesund (79° N show significant positive total column trends. Following the vertical information contained in the ozone FTIR retrievals, we provide partial columns trends for the layers: ground-10 km, 10–18 km, 18–27 km, and 27–42 km, which helps to distinguish the contributions from dynamical and chemical changes on the total column ozone trends. We obtain no statistically significant trends in the ground-10 km layer for five out of the six ground-based stations. We find significant positive trends for the lowermost

  11. Evaluation of tropospheric and stratospheric ozone trends over Western Europe from ground-based FTIR network observations

    Directory of Open Access Journals (Sweden)

    C. Vigouroux

    2008-03-01

    Full Text Available Within the European project UFTIR (Time series of Upper Free Troposphere observations from an European ground-based FTIR network, six ground-based stations in Western Europe, from 79° N to 28° N, all equipped with Fourier Transform infrared (FTIR instruments and part of the Network for the Detection of Atmospheric Composition Change (NDACC, have joined their efforts to evaluate the trend of several direct and indirect greenhouse gases over the period 1995–2004. The retrievals of CO, CH4, C2H6, N2O, CHClF2, and O3 have been optimized. Using the optimal estimation method, some vertical information can be obtained in addition to total column amounts. A bootstrap resampling method has been implemented to determine annual partial and total column trends for the target gases. The present work focuses on the ozone results. The retrieved time series of partial and total ozone columns are validated with ground-based correlative data (Brewer, Dobson, UV-Vis, ozonesondes, and Lidar. The observed total column ozone trends are in agreement with previous studies: 1 no total column ozone trend is seen at the lowest latitude station Izaña (28° N; 2 slightly positive total column trends are seen at the two mid-latitude stations Zugspitze and Jungfraujoch (47° N, only one of them being significant; 3 the highest latitude stations Harestua (60° N, Kiruna (68° N and Ny-Ålesund (79° N show significant positive total column trends. Following the vertical information contained in the ozone FTIR retrievals, we provide partial columns trends for the layers: ground-10 km, 10–18 km, 18–27 km, and 27–42 km, which helps to distinguish the contributions from dynamical and chemical changes on the total column ozone trends. We obtain no statistically significant trends in the ground–10 km layer for five out of the six ground-based stations. We find significant positive trends for the lowermost

  12. Time-related trends in variability of cIMT changes in statin trials.

    Science.gov (United States)

    Davidson, Michael H; Tomassini, Joanne E; Jensen, Erin; Neff, David; Polis, Adam B; Tershakovec, Andrew M

    2016-03-01

    This brief article provides complementary data supporting the results reported in "Changing Characteristics of Statin-related cIMT Trials from 1988 to 2006" [1]. That article described time-related trends in baseline factors and study characteristics that may have influenced the variability of carotid intima media thickness (cIMT) endpoints (mean of mean and maximum common carotid artery [CCA]/cIMT) in published statin trials. In this brief report, additional details for the studies included in the analysis, and further supporting data, including mean of the maximum CCA/cIMT changes and subgroup data (mean and maximum CCA/cIMT) are provided. For the analysis, study-level data was extracted from 17 statin cIMT trials conducted during 1988-2006, selected on the basis of having at least one statin monotherapy arm in the absence of mixed therapy, and baseline- and study-end values for mean mean and mean maximum CCA/cIMT endpoints. The baseline mean CCA/cIMT, maximum mean CCA/cIMT and LDL-C levels, and annualized cIMT changes were estimated for the overall studies, those conducted before/after 2000, and in risk-based subgroups. Interestingly, all 8 studies conducted before 2000 were significant for cIMT change in which patients did not receive prior LLT; whereas after 2000, the results were more variable and in 4 of 6 trials that did not show a significant cIMT change, patients had received prior treatment. Baseline mean maximum cIMT and LDL-C levels, and annualized changes in studies conducted before 2000 were higher than those conducted after 2000, similar to the results reported in the original article for the mean mean cIMT endpoint. These findings were consistent across study populations of patients with CHD risk versus those without, and in studies with greater LDL-C reductions and with thickened baseline cIMT at study entry for both mean and maximum cIMT changes. Taken together, these results are consistent with trends in recent years toward greater use of lipid

  13. Time-related trends in variability of cIMT changes in statin trials

    Directory of Open Access Journals (Sweden)

    Michael H. Davidson

    2016-03-01

    Full Text Available This brief article provides complementary data supporting the results reported in “Changing Characteristics of Statin-related cIMT Trials from 1988 to 2006” [1]. That article described time-related trends in baseline factors and study characteristics that may have influenced the variability of carotid intima media thickness (cIMT endpoints (mean of mean and maximum common carotid artery [CCA]/cIMT in published statin trials. In this brief report, additional details for the studies included in the analysis, and further supporting data, including mean of the maximum CCA/cIMT changes and subgroup data (mean and maximum CCA/cIMT are provided. For the analysis, study-level data was extracted from 17 statin cIMT trials conducted during 1988–2006, selected on the basis of having at least one statin monotherapy arm in the absence of mixed therapy, and baseline- and study-end values for mean mean and mean maximum CCA/cIMT endpoints. The baseline mean CCA/cIMT, maximum mean CCA/cIMT and LDL-C levels, and annualized cIMT changes were estimated for the overall studies, those conducted before/after 2000, and in risk-based subgroups. Interestingly, all 8 studies conducted before 2000 were significant for cIMT change in which patients did not receive prior LLT; whereas after 2000, the results were more variable and in 4 of 6 trials that did not show a significant cIMT change, patients had received prior treatment. Baseline mean maximum cIMT and LDL-C levels, and annualized changes in studies conducted before 2000 were higher than those conducted after 2000, similar to the results reported in the original article for the mean mean cIMT endpoint. These findings were consistent across study populations of patients with CHD risk versus those without, and in studies with greater LDL-C reductions and with thickened baseline cIMT at study entry for both mean and maximum cIMT changes. Taken together, these results are consistent with trends in recent years

  14. Time-related trends in variability of cIMT changes in statin trials.

    Science.gov (United States)

    Davidson, Michael H; Tomassini, Joanne E; Jensen, Erin; Neff, David; Polis, Adam B; Tershakovec, Andrew M

    2016-03-01

    This brief article provides complementary data supporting the results reported in "Changing Characteristics of Statin-related cIMT Trials from 1988 to 2006" [1]. That article described time-related trends in baseline factors and study characteristics that may have influenced the variability of carotid intima media thickness (cIMT) endpoints (mean of mean and maximum common carotid artery [CCA]/cIMT) in published statin trials. In this brief report, additional details for the studies included in the analysis, and further supporting data, including mean of the maximum CCA/cIMT changes and subgroup data (mean and maximum CCA/cIMT) are provided. For the analysis, study-level data was extracted from 17 statin cIMT trials conducted during 1988-2006, selected on the basis of having at least one statin monotherapy arm in the absence of mixed therapy, and baseline- and study-end values for mean mean and mean maximum CCA/cIMT endpoints. The baseline mean CCA/cIMT, maximum mean CCA/cIMT and LDL-C levels, and annualized cIMT changes were estimated for the overall studies, those conducted before/after 2000, and in risk-based subgroups. Interestingly, all 8 studies conducted before 2000 were significant for cIMT change in which patients did not receive prior LLT; whereas after 2000, the results were more variable and in 4 of 6 trials that did not show a significant cIMT change, patients had received prior treatment. Baseline mean maximum cIMT and LDL-C levels, and annualized changes in studies conducted before 2000 were higher than those conducted after 2000, similar to the results reported in the original article for the mean mean cIMT endpoint. These findings were consistent across study populations of patients with CHD risk versus those without, and in studies with greater LDL-C reductions and with thickened baseline cIMT at study entry for both mean and maximum cIMT changes. Taken together, these results are consistent with trends in recent years toward greater use of lipid

  15. Time trends in educational inequalities in cancer mortality in Colombia, 1998–2012

    Science.gov (United States)

    Arroyave, Ivan; Pardo, Constanza

    2016-01-01

    Objectives To evaluate trends in premature cancer mortality in Colombia by educational level in three periods: 1998–2002 with low healthcare insurance coverage, 2003–2007 with rapidly increasing coverage and finally 2008–2012 with almost universal coverage (2008–2012). Setting Colombian population-based, national secondary mortality data. Participants We included all (n=188 091) cancer deaths occurring in the age group 20–64 years between 1998 and 2012, excluding only cases with low levels of quality of registration (n=2902, 1.5%). Primary and secondary outcome measures In this descriptive study, we linked mortality data of ages 20–64 years to census data to obtain age-standardised cancer mortality rates by educational level. Using Poisson regression, we modelled premature mortality by educational level estimating rate ratios (RR), relative index of inequality (RII) and the Slope Index of Inequality (SII). Results Relative measures showed increased risks of dying among the lower educated compared to the highest educated; this tendency was stronger in women (RRprimary 1.49; RRsecondary 1.22, both p<0.0001) than in men (RRprimary 1.35; RRsecondary 1.11, both p<0.0001). In absolute terms (SII), cancer caused a difference per 100 000 deaths between the highest and lowest educated of 20.5 in males and 28.5 in females. RII was significantly higher among women and the younger age categories. RII decreased between the first and second periods; afterwards (2008–2012), it increased significantly back to their previous levels. Among women, no significant increases or declines in cancer mortality over time were observed in recent periods in the lowest educated group, whereas strong recent declines were observed in those with secondary education or higher. Conclusions Educational inequalities in cancer mortality in Colombia are increasing in absolute and relative terms, and are concentrated in young age categories. This trend was not curbed by increases in

  16. The Knowledge-based Economy: Trends and Implications for Pakistan

    OpenAIRE

    Rukhsana Kalim; Suleman Aziz Lodhi

    2002-01-01

    Economic history has witnessed transformation from Agriculture based to Manufacturing based economies over the time. This transformation had its effects on social structure of the communities, as new types of jobs were created in the manufacturing industries, and new life styles of metropolitan culture evolved. A similar transformation is now taking place as; business has grown global over the last years, making the present business atmosphere further competitive, fast and fluid. Technologica...

  17. On the time-varying trend in global-mean surface temperature

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zhaohua [Florida State University, Department of Meteorology and Center for Ocean-Atmospheric Prediction Studies, Tallahassee, FL (United States); Huang, Norden E. [National Central University, Research Center for Adaptive Data Analysis Center, Chungli (China); Wallace, John M.; Smoliak, Brian V. [University of Washington, Department of Atmospheric Sciences, Seattle, WA (United States); Chen, Xianyao [State Oceanic Administration, The First Institute of Oceanography, Qingdao (China)

    2011-08-15

    The Earth has warmed at an unprecedented pace in the decades of the 1980s and 1990s (IPCC in Climate change 2007: the scientific basis, Cambridge University Press, Cambridge, 2007). In Wu et al. (Proc Natl Acad Sci USA 104:14889-14894, 2007) we showed that the rapidity of the warming in the late twentieth century was a result of concurrence of a secular warming trend and the warming phase of a multidecadal ({proportional_to}65-year period) oscillatory variation and we estimated the contribution of the former to be about 0.08 C per decade since {proportional_to}1980. Here we demonstrate the robustness of those results and discuss their physical links, considering in particular the shape of the secular trend and the spatial patterns associated with the secular trend and the multidecadal variability. The shape of the secular trend and rather globally-uniform spatial pattern associated with it are both suggestive of a response to the buildup of well-mixed greenhouse gases. In contrast, the multidecadal variability tends to be concentrated over the extratropical Northern Hemisphere and particularly over the North Atlantic, suggestive of a possible link to low frequency variations in the strength of the thermohaline circulation. Depending upon the assumed importance of the contributions of ocean dynamics and the time-varying aerosol emissions to the observed trends in global-mean surface temperature, we estimate that up to one third of the late twentieth century warming could have been a consequence of natural variability. (orig.)

  18. Time trends in the aetiology of prosthetic joint infections: a multicentre cohort study.

    Science.gov (United States)

    Benito, N; Franco, M; Ribera, A; Soriano, A; Rodriguez-Pardo, D; Sorlí, L; Fresco, G; Fernández-Sampedro, M; Dolores Del Toro, M; Guío, L; Sánchez-Rivas, E; Bahamonde, A; Riera, M; Esteban, J; Baraia-Etxaburu, J M; Martínez-Alvarez, J; Jover-Sáenz, A; Dueñas, C; Ramos, A; Sobrino, B; Euba, G; Morata, L; Pigrau, C; Coll, P; Mur, I; Ariza, J

    2016-08-01

    It is important to know the spectrum of the microbial aetiology of prosthetic joint infections (PJIs) to guide empiric treatment and establish antimicrobial prophylaxis in joint replacements. There are no available data based on large contemporary patient cohorts. We sought to characterize the causative pathogens of PJIs and to evaluate trends in the microbial aetiology. We hypothesized that the frequency of antimicrobial-resistant organisms in PJIs has increased in the recent years. We performed a cohort study in 19 hospitals in Spain, from 2003 to 2012. For each 2-year period (2003-2004 to 2011-2012), the incidence of microorganisms causing PJIs and multidrug-resistant bacteria was assessed. Temporal trends over the study period were evaluated. We included 2524 consecutive adult patients with a diagnosis of PJI. A microbiological diagnosis was obtained for 2288 cases (90.6%). Staphylococci were the most common cause of infection (1492, 65.2%). However, a statistically significant rising linear trend was observed for the proportion of infections caused by Gram-negative bacilli, mainly due to the increase in the last 2-year period (25% in 2003-2004, 33.3% in 2011-2012; p 0.024 for trend). No particular species contributed disproportionally to this overall increase. The percentage of multidrug-resistant bacteria PJIs increased from 9.3% in 2003-2004 to 15.8% in 2011-2012 (p 0.008), mainly because of the significant rise in multidrug-resistant Gram-negative bacilli (from 5.3% in 2003-2004 to 8.2% in 2011-2012; p 0.032). The observed trends have important implications for the management of PJIs and prophylaxis in joint replacements. PMID:27181408

  19. Time trends of incidence of digestive system cancers in changle of China during :1988-2002

    Institute of Scientific and Technical Information of China (English)

    Jun Tian; Jian-Shun Chen

    2006-01-01

    AIM: To analyze the incidence of digestive system cancer in Changle of China over a 15-year period.METHODS: The datasets were presented as timeseries of China-standardized annual incidence during 1988-2002. Linear regression model was used to analyze the incidence of stomach, liver, esophagus and colorectal cancers.RESULTS: Linear regression models for the time-series of stomach and esophagus cancer incidences for both men and women were statistically significant (P<0.05);Regression models for liver cancer and for colorectal cancer were statistically significant for men (P<0.05).CONCLUSION: The incidence rates of stomach and esophagus cancers for both men and women had down tendencies. For men, liver cancer had a down trend of the incidence and colorectal cancer had an upward trend of the incidence rate.

  20. Clinical signs indicative of temporomandibular disorders in adults: time trends and associated factors.

    Science.gov (United States)

    Köhler, Alkisti Anastassaki; Hugoson, Anders; Magnusson, Tomas

    2013-01-01

    The study aimed to examine possible time trends in the prevalence of clinical signs indicative of temporomandibular disorder (TMD) in an adult population, to analyse possible associations between TMD signs and associated factors and to estimate the need for TMD treatment. Three independent, stratified and randomly selected samples of around 100 individuals in the age groups of 20, 30, 40, 50, 60 and 70 years participated in the Jönköping studies in 1983,1993 and 2003. The study material consisted of 1,693 subjects who, after answering a questionnaire and being interviewed about the presence of TMD symptoms, were clinically examined in terms of the presence of TMD signs according to the Clinical Dysfunction Index (Di) by Helkimo. Associations between clinical signs and the Di as dependent variables and each of the independent variables of age group, gender, reported bruxism, trauma, self-perceived healthiness and the year of investigation were analysed in binary logistic regression models. Estimates of the need for TMD treatment were based on the presence of a combination of severe symptoms and clinical signs. The prevalence of severely impaired jaw movement capacity, relating to horizontal movements, had increased in 2003. The prevalence of muscle pain and temporomandibular joint pain upon posterior palpation was found to vary statistically significantly between 1993 and 2003. Gender differences were noted in these changes overtime. Female gender, advancing age, awareness of bruxism, self-perceived health impairment and the wearing of complete dentures were associated with TMD signs and a higher degree of clinical dysfunction. The estimated need for TMD treatment increased from 5% in 1983 to 8% in 2003 and was higher in women than in men. In conclusion, the results indicate that the prevalence of some TMD signs and of estimated treatment need increased during the period 1983-2003.

  1. Defining a Trend for a Time Series Which Makes Use of the Intrinsic Time-Scale Decomposition

    CERN Document Server

    Restrepo, Juan M; Comeau, Darin; Flaschka, Hermann

    2014-01-01

    We propose criteria that define a trend for time series with inherent multi-scale features. We call this trend the {\\it tendency} of a time series. The tendency is defined empirically by a set of criteria and captures the large-scale temporal variability of the original signal as well as the most frequent events in its histogram. Among other properties, the tendency has a variance no larger than that of the original signal; the histogram of the difference between the original signal and the tendency is as symmetric as possible; and with reduced complexity, the tendency captures essential features of the signal. To find the tendency we first use the Intrinsic Time-Scale Decomposition (ITD) of the signal, introduced in 2007 by Frei and Osorio, to produce a set of candidate tendencies. We then apply the criteria to each of the candidates to single out the one that best agrees with them. While the criteria for the tendency are independent of the signal decomposition scheme, it is found that the ITD is a simple an...

  2. Fast or slow food? Explaining trends in food-related time in the Netherlands, 1975–2005

    OpenAIRE

    Mandemakers, J. J.; Roeters, Anne

    2014-01-01

    The current study analysed trends in the time spent preparing and consuming food and the frequency of outsourcing (going out for dinner and take-out) in the Netherlands from 1975 to 2005. We investigated differences between trends on week and weekend days and for different socio-demographic groups. Analyses using pooled data from the Dutch Time Use Survey (N¼13,421) revealed a downward trend in minutes preparing and consuming food and an increase in outsourcing. This overall downward trend co...

  3. Fuzzy forecasting based on two-factors second-order fuzzy-trend logical relationship groups and the probabilities of trends of fuzzy logical relationships.

    Science.gov (United States)

    Chen, Shyi-Ming; Chen, Shen-Wen

    2015-03-01

    In this paper, we present a new method for fuzzy forecasting based on two-factors second-order fuzzy-trend logical relationship groups and the probabilities of trends of fuzzy-trend logical relationships. Firstly, the proposed method fuzzifies the historical training data of the main factor and the secondary factor into fuzzy sets, respectively, to form two-factors second-order fuzzy logical relationships. Then, it groups the obtained two-factors second-order fuzzy logical relationships into two-factors second-order fuzzy-trend logical relationship groups. Then, it calculates the probability of the "down-trend," the probability of the "equal-trend" and the probability of the "up-trend" of the two-factors second-order fuzzy-trend logical relationships in each two-factors second-order fuzzy-trend logical relationship group, respectively. Finally, it performs the forecasting based on the probabilities of the down-trend, the equal-trend, and the up-trend of the two-factors second-order fuzzy-trend logical relationships in each two-factors second-order fuzzy-trend logical relationship group. We also apply the proposed method to forecast the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) and the NTD/USD exchange rates. The experimental results show that the proposed method outperforms the existing methods.

  4. Temporal trends in non-occupational sedentary behaviours from Australian Time Use Surveys 1992, 1997 and 2006

    OpenAIRE

    Chau Josephine Y; Merom Dafna; Grunseit Anne; Rissel Chris; Bauman Adrian E; van der Ploeg Hidde P

    2012-01-01

    Abstract Background Current epidemiological data highlight the potential detrimental associations between sedentary behaviours and health outcomes, yet little is known about temporal trends in adult sedentary time. This study used time use data to examine population trends in sedentary behaviours in non-occupational domains and more specifically during leisure time. Methods We conducted secondary analysis of population representative data from the Australian Time Use Surveys 1992, 1997 and 20...

  5. Recent Trends in Field-Effect Transistors-Based Immunosensors

    Directory of Open Access Journals (Sweden)

    Ana Carolina Mazarin de Moraes

    2016-10-01

    Full Text Available Immunosensors are analytical platforms that detect specific antigen-antibody interactions and play an important role in a wide range of applications in biomedical clinical diagnosis, food safety, and monitoring contaminants in the environment. Field-effect transistors (FET immunosensors have been developed as promising alternatives to conventional immunoassays, which require complicated processes and long-time data acquisition. The electrical signal of FET-based immunosensors is generated as a result of the antigen-antibody conjugation. FET biosensors present real-time and rapid response, require small sample volume, and exhibit higher sensitivity and selectivity. This review brings an overview on the recent literature of FET-based immunosensors, highlighting a diversity of nanomaterials modified with specific receptors as immunosensing platforms for the ultrasensitive detection of various biomolecules.

  6. Forecasting long-run coal price in China: a shifting trend time-series approach

    Energy Technology Data Exchange (ETDEWEB)

    Dong, B.M.; Li, X.F.; Lin, B.Q. [Xiamen University, Xiamen (China)

    2010-08-15

    The paper studies the behavior of mid- to long-run real coal price in the Chinese market. The problem is of great importance because the coal takes a 70% share in China's energy mix, and China is the world's second largest carbon emitter. An accurate forecast in coal price is crucial in predicting China's future energy consumption mix as well as the private sector's energy-type-related investment decisions. In estimation and forecasting, the shifting trend time-series model suggested by Robert Pindyck is used to capture the technological progress that is unobservable to the econometrician. It is found that the shifting trend model with continuous and random changes in price level and trend outperforms plain vanilla ARIMA models. It is argued that the model postulated by Pindyck is robust even in a transition economy where energy prices are subject to relatively rigid regulatory control. Out-of-sample forecasts are provided.

  7. Twenty four year time trends in fats and cholesterol intake by adolescents. Warsaw Adolescents Study

    Directory of Open Access Journals (Sweden)

    Charzewska Jadwiga

    2015-06-01

    Full Text Available The objective of this study was to determine time trends (1982–2006 in total fat intake and changes in fatty acid structure intake in adolescents from Warsaw in view of increasing prevalence of obesity. Data come from four successive surveys randomly selected samples of adolescents (aged 11–15 years old, from Warsaw region. In total 9747 pupils have been examined, with response rate varying from 55% to 87% depending on year. Surveys were done always in the spring season of the year. Food intake was assessed by using 24 hours recall method of consumption by the pupils all products, including enriched, dishes and beverages as well as diet supplements, in the last 24 hours preceding the examination. The content of energy and nutrients was calculated by means of own computer softwares (DIET 2 and 4, taking into account successive revisions of the tables of food composition and nutritional values, as well as current Polish DRI. A significant decreasing trend was found in intake of total fat, of saturated fatty acids (SFA and cholesterol. The percentage of energy from total fat, also decreased both in boys (to 35,1% and girls (to 33,7%, what failed to reach the desired level below 30% of energy from fat which is recommended. Also significant decrease of SFA consumption was not satisfactory enough to approach the values <10% of energy recommended as was from 13% to 15%. Decreasing trends in fat intake was not in accordance with the trend in obesity prevalence in the adolescents as average BMI is going up. To stabilize the health-oriented changes especially in the diets of adolescents, further activity is desired from professionals working with prevention of adolescents obesity.

  8. Pattern recognition of Landsat data based upon temporal trend analysis

    Science.gov (United States)

    Engvall, J. L.; Tubbs, J. D.; Holmes, Q. A.

    1977-01-01

    The Delta Classifier defined as an agricultural crop classification scheme employing a temporal trend procedure is applied to more than 100 different Landsat data sets collected during the 1974-1975 growing season throughout the major wheat-producing regions of the United States. The classification approach stresses examination of temporal trends of the Landsat mean vectors of crops in the absence of corresponding ground truth information. It is shown that the resulting classifications compare favorably to ground truth estimates for wheat proportion in those cases where ground truth is available, and that the temporal trend procedure yields estimates of the wheat proportion that are comparable to the best results from maximum likelihood classification with photointerpreter-defined training fields.

  9. 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.

  10. Long term trends in prevalence of neural tube defects in Europe: population based study

    Science.gov (United States)

    Loane, Maria; de Walle, Hermien; Arriola, Larraitz; Addor, Marie-Claude; Barisic, Ingeborg; Beres, Judit; Bianchi, Fabrizio; Dias, Carlos; Draper, Elizabeth; Garne, Ester; Gatt, Miriam; Haeusler, Martin; Klungsoyr, Kari; Latos-Bielenska, Anna; Lynch, Catherine; McDonnell, Bob; Nelen, Vera; Neville, Amanda J; O’Mahony, Mary T; Queisser-Luft, Annette; Rankin, Judith; Rissmann, Anke; Ritvanen, Annukka; Rounding, Catherine; Sipek, Antonin; Tucker, David; Verellen-Dumoulin, Christine; Wellesley, Diana; Dolk, Helen

    2015-01-01

    Study question What are the long term trends in the total (live births, fetal deaths, and terminations of pregnancy for fetal anomaly) and live birth prevalence of neural tube defects (NTD) in Europe, where many countries have issued recommendations for folic acid supplementation but a policy for mandatory folic acid fortification of food does not exist? Methods This was a population based, observational study using data on 11 353 cases of NTD not associated with chromosomal anomalies, including 4162 cases of anencephaly and 5776 cases of spina bifida from 28 EUROCAT (European Surveillance of Congenital Anomalies) registries covering approximately 12.5 million births in 19 countries between 1991 and 2011. The main outcome measures were total and live birth prevalence of NTD, as well as anencephaly and spina bifida, with time trends analysed using random effects Poisson regression models to account for heterogeneities across registries and splines to model non-linear time trends. Summary answer and limitations Overall, the pooled total prevalence of NTD during the study period was 9.1 per 10 000 births. Prevalence of NTD fluctuated slightly but without an obvious downward trend, with the final estimate of the pooled total prevalence of NTD in 2011 similar to that in 1991. Estimates from Poisson models that took registry heterogeneities into account showed an annual increase of 4% (prevalence ratio 1.04, 95% confidence interval 1.01 to 1.07) in 1995-99 and a decrease of 3% per year in 1999-2003 (0.97, 0.95 to 0.99), with stable rates thereafter. The trend patterns for anencephaly and spina bifida were similar, but neither anomaly decreased substantially over time. The live birth prevalence of NTD generally decreased, especially for anencephaly. Registration problems or other data artefacts cannot be excluded as a partial explanation of the observed trends (or lack thereof) in the prevalence of NTD. What this study adds In the absence of mandatory fortification

  11. Methodological issues in analyzing time trends in biologic fertility: protection bias

    DEFF Research Database (Denmark)

    Key, Jane; Best, Nicky; Joffe, Michael;

    2009-01-01

    One method of assessing biologic fertility is to measure time to pregnancy (TTP). Accidental pregnancies do not generate a valid TTP value and lead to nonrandom missing data if couples experiencing accidental pregnancies are more fertile than the general population. If factors affecting the rate of...... accidental pregnancies, such as availability of effective contraception and induced abortion, vary over time, then the result may be protection bias in the estimates of fertility time trends. Six European data sets were analyzed to investigate whether evidence of protection bias exists in TTP studies of...... simulated data. Where protection bias is suspected, the authors demonstrate use of 2 multiple imputation methods to generate realizations for the missing TTP values for accidental pregnancies. Simulation studies show that both methods successfully reduce or eliminate protection bias. The authors also...

  12. Gender-Based Violence in India: Long-Term Trends

    Science.gov (United States)

    Simister, John; Mehta, Parnika S.

    2010-01-01

    This article examines long-term trends in Indian society regarding domestic violence between husband and wife, and attitudes to such violence. This article analyzes crime data and uses data from several Indian household surveys: "Work Attitudes and Spending" surveys (1992 to 2007); "World Values Survey" (1990, 1995, 2001, and 2006); and…

  13. Trends in hydrodesulfurization catalysis based on realistic surface models

    DEFF Research Database (Denmark)

    Moses, P.G.; Grabow, L.C.; Fernandez Sanchez, Eva;

    2014-01-01

    Trends in hydrodesulfurization (HDS) activity are investigated on the basis of surface properties calculated by density functional theory for a series of HDS catalysts. It is shown that approximately linear correlations exist between HS group binding energies and activation barriers of key elemen...

  14. Fast or slow food? Explaining trends in food-related time in the Netherlands, 1975-2005

    NARCIS (Netherlands)

    Mandemakers, J.J.; Roeters, A.

    2015-01-01

    The current study analysed trends in the time spent preparing and consuming food and the frequency of outsourcing (going out for dinner and take-out) in the Netherlands from 1975 to 2005. We investigated differences between trends on week and weekend days and for different socio-demographic groups.

  15. Fast or slow food? Explaining trends in food-related time in the Netherlands, 1975–2005

    NARCIS (Netherlands)

    Mandemakers, J.J.; Roeters, Anne

    2014-01-01

    The current study analysed trends in the time spent preparing and consuming food and the frequency of outsourcing (going out for dinner and take-out) in the Netherlands from 1975 to 2005. We investigated differences between trends on week and weekend days and for different socio-demographic groups.

  16. Demonstrating trend reversal of groundwater quality in relation to time of recharge determined by 3H/3He

    NARCIS (Netherlands)

    Visser, A.; Broers, H.P.; Grift, B. van der; Bierkens, M.F.P.

    2007-01-01

    Recent EU legislation is directed to reverse the upward trends in the concentrations of agricultural pollutants in groundwater. However, uncertainty of the groundwater travel time towards the screens of the groundwater quality monitoring networks complicates the demonstration of trend reversal. We i

  17. Effects of dating errors on nonparametric trend analyses of speleothem time series

    Directory of Open Access Journals (Sweden)

    M. Mudelsee

    2012-10-01

    Full Text Available A fundamental problem in paleoclimatology is to take fully into account the various error sources when examining proxy records with quantitative methods of statistical time series analysis. Records from dated climate archives such as speleothems add extra uncertainty from the age determination to the other sources that consist in measurement and proxy errors. This paper examines three stalagmite time series of oxygen isotopic composition (δ18O from two caves in western Germany, the series AH-1 from the Atta Cave and the series Bu1 and Bu4 from the Bunker Cave. These records carry regional information about past changes in winter precipitation and temperature. U/Th and radiocarbon dating reveals that they cover the later part of the Holocene, the past 8.6 thousand years (ka. We analyse centennial- to millennial-scale climate trends by means of nonparametric Gasser–Müller kernel regression. Error bands around fitted trend curves are determined by combining (1 block bootstrap resampling to preserve noise properties (shape, autocorrelation of the δ18O residuals and (2 timescale simulations (models StalAge and iscam. The timescale error influences on centennial- to millennial-scale trend estimation are not excessively large. We find a "mid-Holocene climate double-swing", from warm to cold to warm winter conditions (6.5 ka to 6.0 ka to 5.1 ka, with warm–cold amplitudes of around 0.5‰ δ18O; this finding is documented by all three records with high confidence. We also quantify the Medieval Warm Period (MWP, the Little Ice Age (LIA and the current warmth. Our analyses cannot unequivocally support the conclusion that current regional winter climate is warmer than that during the MWP.

  18. Variability and trends of ocean acidification in the Southern California Current System: A time series from Santa Monica Bay

    Science.gov (United States)

    Leinweber, A.; Gruber, N.

    2013-07-01

    We investigate the temporal variability and trends of pH and of the aragonite saturation state, Ωarag, in the southern California Current System on the basis of a 6 year time series from Santa Monica Bay, using biweekly observations of dissolved inorganic carbon and combined calculated and measured alkalinity. Median values of pH and Ωarag in the upper 20 m are comparable to observations from the subtropical gyres, but the temporal variability is at least a factor of 5 larger, primarily driven by short-term upwelling events and mesoscale processes. Ωarag and pH decrease rapidly with depth, such that the saturation horizon is reached already at 130 m, on average, but it occasionally shoals to as low as 30 m. No statistically significant linear trends emerge in the upper 100 m, but Ωarag and pH decrease, on average, at rates of -0.009±0.006 yr-1 and -0.004±0.003 yr-1 in the 100-250 m depth range. These are somewhat larger, but not statistically different from the expected trends based on the recent increase in atmospheric CO2. About half of the variability in the deseasonalized data can be explained by the El Niño Southern Oscillation, with warm phases (El Niño) being associated with above normal pH and Ωarag. The observed variability and trend in Ωarag and pH is well captured by a multiple linear regression model on the basis of a small number of readily observable independent variables. This permits the estimation of these variables for related sites in the region.

  19. Simulation of Change Trend of Drought in Shaanxi Province in Future Based on PRECIS Model

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to predict the change trend of drought in Shaanxi Province in future. [Method] Based on the regional climate model PRECIS from Hadley Climate Center, British Meteorological Bureau, taking precipitation anomaly percentage as assessment index, the change trend of drought in Shaanxi Province in reference years (1971-1990) was simulated, and the change trend of drought in Shaanxi Province from 2071 to 2100 was predicted. [Result] The simulated value of drought frequency in reference year...

  20. Time trend and clinical pattern of extrapulmonary tuberculosis in Serbia, 1993-2007

    Directory of Open Access Journals (Sweden)

    Pešut Dragica P.

    2012-01-01

    Full Text Available Background/Aim. Increased incidence of extrapulmonary tuberculosis (XPTB is reported worldwide. Serbia is a country in socio-economic transition period with lowmiddle HIV prevalence and intermediate-to-low tuberculosis (TB incidence rate, 100% directly observed treatment (DOT coverage, and mandatory BCG vaccination at birth. The aim of the study was to examine the incidence trend and clinical features of XPTB in Serbia during a 15-year period. Methods. This retrospective observational study included XPTB cases diagnosed in the period between 1st January 1993 and 31st Decembre 2007, according to the reports of the National Referral Institute of Lung Diseases and Tuberculosis in Belgrade and Central Tuberculosis Register. Population estimates with extrapolations were based on 1991 and 2002 census data. Results. While the overall TB incidence rate showed a slight, not significant decreasing trend (p = 0.535, a significant increase was found for XPTB (y = 1.7996 + 0.089x; R2 = 0.4141; p = 0.01. A total of 2,858 XPTB cases (newly diagnosed and 10% relapses gave an average age specific incidence rate of 2.51/100,000 population (95% confidence interval, SD = 0.6182 with 8.9% annual increase. The male-to-female ratio was 0.54. Lymph nodes were most frequently affected site (48.5% followed by genitourinary (20.5%, pleural (12%, and osseo-arthicular (10.3% TB. Treatment outcome was successful in 88.29% of patients (cured and completed, 3.64% died, 5.18% interrupted, 0.57% displaced, and 2.3% unknown. Conclusion. Increasing trend of XPTB incidence rate may be a result of increased morbidity due to still present risk factors, possible higher detection rate in Serbia and better notification. A high coverage of newborns with BCG vaccination at birth might contribute to a decreased number and rare XPTB cases in children.

  1. Time trends in socioeconomic inequalities in stunting prevalence: analyses of repeated national surveys

    Science.gov (United States)

    Restrepo-Méndez, María Clara; Barros, Aluísio JD; Black, Robert E; Victora, Cesar G

    2016-01-01

    Objective Much is known about national trends in child undernutrition, but there is little information on how socioeconomic inequalities are evolving over time. We aimed to assess socioeconomic inequalities in stunting prevalence over time. Setting Nationally representative household surveys from 25 low and middle income countries. Design We selected nationally representative surveys carried out since the mid-1990s for which information was available on asset indices and on child anthropometry. We identified twenty-five countries which had at least two surveys over an interval of 10 or more years, totaling 87 surveys. Stunting prevalence was calculated according to wealth quintiles. Absolute and relative inequalities were calculated, and time trends were obtained by regression. Results National prevalence declined significantly in 22 of the 25 countries. In 18 out of 25 countries, relative reductions among the rich than among the poor. Overall, there was no indication that inequalities improved. Striking examples are Nepal, with a 17·0 percent points decline in stunting per decade, but where inequalities increased sharply, and Brazil where stunting fell by 6·7 percent points and inequalities were all but eliminated. Conclusions Global progress in reducing stunting has not been accompanied by improved equity, but countries varied markedly in how successful they were in reducing prevalence among the poorest children. It is important to document how some countries were able to reduce inequalities, so that these lessons can be used to foster global progress, particularly in light of the increased importance of within-country inequalities in the post-2015 agenda. PMID:25521530

  2. Time trend in hospitalised chronic lower respiratory diseases among Danish building and construction workers, 1981-2009

    DEFF Research Database (Denmark)

    Tüchsen, Finn; Hannerz, Harald; Mølgaard, Ellen Fisher;

    2012-01-01

    To show trends in age-standardised hospital admission ratios (SHR) for chronic lower respiratory diseases, estimated for Danish construction workers over three time periods (1981-1990, 1991-2000, 2001-2009).......To show trends in age-standardised hospital admission ratios (SHR) for chronic lower respiratory diseases, estimated for Danish construction workers over three time periods (1981-1990, 1991-2000, 2001-2009)....

  3. Ozone balloon soundings at Payerne (Switzerland): Reevaluation of the time series 1967-2002 and trend analysis

    Science.gov (United States)

    Jeannet, P.; Stübi, R.; Levrat, G.; Viatte, P.; Staehelin, J.

    2007-06-01

    This study documents the history of the Payerne (Switzerland) ozone series obtained with the Brewer-Mast sonde from the end of 1966 until the change to the electrochemical concentration cell (ECC) sonde in autumn 2002, as well as the reevaluation of the original data. Several corrections were made in order to improve the homogeneity and the quality of the time series. We furthermore derived long-term trends for the reevaluated time series using atmospheric variables in a stepwise regression model. In the stratosphere, trends over the 1970-2002 period remain nearly the same as over periods ending a few years earlier. For tropospheric ozone trends, a hockey stick model allowing for a change in trend in 1990 was used and a sensitivity analysis with different data sets was carried out. Besides the standard World Meteorological Organization (WMO) data evaluation procedure, we used alternative data sets (1) accounting for the preflight laboratory calibrations, or (2) ignoring the total ozone normalization, (3) as well as correcting for chemical interference with SO2. With all data sets, tropospheric trends were strongly positive in all seasons over the 1967-1989 period. In the 1990-2002 period, winter trends remained positive over the whole troposphere with all data sets, whereas in the other seasons, trends were generally negative near the ground and shifted to zero or positive values with increasing altitude in the troposphere. The alternative evaluation procedures strongly affect the derived tropospheric trends in the 1990-2002 period and their uncertainties.

  4. Interfractional trend analysis of dose differences based on 2D transit portal dosimetry

    Science.gov (United States)

    Persoon, L. C. G. G.; Nijsten, S. M. J. J. G.; Wilbrink, F. J.; Podesta, M.; Snaith, J. A. D.; Lustberg, T.; van Elmpt, W. J. C.; van Gils, F.; Verhaegen, F.

    2012-10-01

    Dose delivery of a radiotherapy treatment can be influenced by a number of factors. It has been demonstrated that the electronic portal imaging device (EPID) is valuable for transit portal dosimetry verification. Patient related dose differences can emerge at any time during treatment and can be categorized in two types: (1) systematic—appearing repeatedly, (2) random—appearing sporadically during treatment. The aim of this study is to investigate how systematic and random information appears in 2D transit dose distributions measured in the EPID plane over the entire course of a treatment and how this information can be used to examine interfractional trends, building toward a methodology to support adaptive radiotherapy. To create a trend overview of the interfractional changes in transit dose, the predicted portal dose for the different beams is compared to a measured portal dose using a γ evaluation. For each beam of the delivered fraction, information is extracted from the γ images to differentiate systematic from random dose delivery errors. From the systematic differences of a fraction for a projected anatomical structures, several metrics are extracted like percentage pixels with |γ| > 1. We demonstrate for four example cases the trends and dose difference causes which can be detected with this method. Two sample prostate cases show the occurrence of a random and systematic difference and identify the organ that causes the difference. In a lung cancer case a trend is shown of a rapidly diminishing atelectasis (lung fluid) during the course of treatment, which was detected with this trend analysis method. The final example is a breast cancer case where we show the influence of set-up differences on the 2D transit dose. A method is presented based on 2D portal transit dosimetry to record dose changes throughout the course of treatment, and to allow trend analysis of dose discrepancies. We show in example cases that this method can identify the causes of

  5. Predicting magnetostructural trends in FeRh-based ternary systems

    Science.gov (United States)

    Barua, Radhika; Jiménez-Villacorta, Félix; Lewis, L. H.

    2013-09-01

    Correlations between magnetic transition temperatures and the average weighted valence band electron concentration ((s + d) electrons/atom) have led to the development of a phenomenological model that predicts the influence of elemental substitution on the magnetostructural response of bulk B2-ordered Fe(Rh1-xMx) or (Fe1-xMx)Rh alloys (M = transition elements; x FeRh with Cu and Au additions. The data and associated trends indicate that the lattice and electronic free energies are both equally important in driving the magnetostructural transition in the bulk FeRh system.

  6. Prediction of time trends in recovery of cognitive function after mild head injury

    DEFF Research Database (Denmark)

    Müller, Kay; Ingebrigtsen, Tor; Wilsgaard, Tom;

    2009-01-01

    OBJECTIVE: To investigate relations between predictors and outcomes, and especially to identify predictors influencing the time trend in recovery after mild traumatic brain injury. METHODS: We included 59 patients with mild head injury in a prospective study. They underwent comprehensive assessment...... change. RESULTS: A Glasgow Coma Scale score of less than 15, traumatic brain injury demonstrated with computed tomography, magnetic resonance imaging, and serum S-100B greater than 0.14 microg/L predicted impaired cognitive performance both at baseline and after 6 months; APOE genotype did not....... There was significant improvement of performance after 6 months. APOE-epsilon4 genotype was the only independent factor significantly predicting less improvement. CONCLUSION: The presence of the APOE-epsilon4 allele predicts less recovery of cognitive function after mild head injury....

  7. Measuring trends in performance across time: providing information to cancer patients.

    Science.gov (United States)

    Fitch, Margaret I; McAndrew, Alison; Harth, Tamara

    2013-01-01

    Providing relevant, up-to-date information is identified as a quality standard of cancer care. Cancer programs need to be able to evaluate whether they are meeting the standard and to monitor their performance on an ongoing basis. Routine collection of clearly defined data, using reliable and valid measures, provides cancer program leaders with dependable information upon which to make decisions and monitor trends in performance over time. This article describes one cancer centre's experience in using standardized data collection regarding provision of patient information. The Cancer Patient Information Importance-Satisfaction Scale has been administered routinely in an outpatient setting over eight years. The profile we create from the data assists us in making informed decisions about patient education initiatives.

  8. Regression analysis of time trends in perinatal mortality in Germany 1980-1993.

    Science.gov (United States)

    Scherb, H; Weigelt, E; Brüske-Hohlfeld, I

    2000-02-01

    Numerous investigations have been carried out on the possible impact of the Chernobyl accident on the prevalence of anomalies at birth and on perinatal mortality. In many cases the studies were aimed at the detection of differences of pregnancy outcome measurements between regions or time periods. Most authors conclude that there is no evidence of a detrimental physical effect on congenital anomalies or other outcomes of pregnancy following the accident. In this paper, we report on statistical analyses of time trends of perinatal mortality in Germany. Our main intention is to investigate whether perinatal mortality, as reflected in official records, was increased in 1987 as a possible effect of the Chernobyl accident. We show that, in Germany as a whole, there was a significantly elevated perinatal mortality proportion in 1987 as compared to the trend function. The increase is 4.8% (p = 0.0046) of the expected perinatal death proportion for 1987. Even more pronounced levels of 8.2% (p = 0. 0458) and 8.5% (p = 0.0702) may be found in the higher contaminated areas of the former German Democratic Republic (GDR), including West Berlin, and of Bavaria, respectively. To investigate the impact of statistical models on results, we applied three standard regression techniques. The observed significant increase in 1987 is independent of the statistical model used. Stillbirth proportions show essentially the same behavior as perinatal death proportions, but the results for all of Germany are nonsignificant due to the smaller numbers involved. Analysis of the association of stillbirth proportions with the (137)Cs deposition on a district level in Bavaria discloses a significant relationship. Our results are in contrast to those of many analyses of the health consequences of the Chernobyl accident and contradict the present radiobiologic knowledge. As we are dealing with highly aggregated data, other causes or artifacts may explain the observed effects. Hence, the findings

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

    International Nuclear Information System (INIS)

    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)

  10. Accounting for heterogeneity among treatment sites and time trends in developing crash modification functions.

    Science.gov (United States)

    Sacchi, Emanuele; Sayed, Tarek

    2014-11-01

    Collision modification factors (CMFs) are commonly used to quantify the impact of safety countermeasures. The CMFs obtained from observational before-after (BA) studies are usually estimated by averaging the safety impact (i.e., index of effectiveness) for a group of treatment sites. The heterogeneity among the treatment locations, in terms of their characteristics, and the effect of this heterogeneity on safety treatment effectiveness are usually ignored. This is in contrast to treatment evaluations in other fields like medical statistics where variations in the magnitude (or in the direction) of response to the same treatment given to different patients are considered. This paper introduces an approach for estimating a CMFunction from BA safety studies that account for variable treatment location characteristics (heterogeneity). The treatment sites heterogeneity was incorporated into the CMFunction using fixed-effects and random-effects regression models. In addition to heterogeneity, the paper also advocates the use of CMFunctions with a time variable to acknowledge that the safety treatment (intervention) effects do not occur instantaneously but are spread over future time. This is achieved using non-linear intervention (Koyck) models, developed within a hierarchical full Bayes (FB) context. To demonstrate the approach, a case study is presented to evaluate the safety effectiveness of the "Signal Head Upgrade Program" recently implemented in the city of Surrey (British Columbia, Canada), where signal visibility was improved at several urban signalized intersections. The results demonstrated the importance of considering treatment sites heterogeneity and time trends when developing CMFunctions. PMID:25033279

  11. The Living Planet Index: using species population time series to track trends in biodiversity

    OpenAIRE

    Loh, Jonathan; Green, Rhys E; Ricketts, Taylor; Lamoreux, John; Jenkins, Martin; Kapos, Valerie; Randers, Jorgen

    2005-01-01

    The Living Planet Index was developed to measure the changing state of the world's biodiversity over time. It uses time-series data to calculate average rates of change in a large number of populations of terrestrial, freshwater and marine vertebrate species. The dataset contains about 3000 population time series for over 1100 species. Two methods of calculating the index are outlined: the chain method and a method based on linear modelling of log-transformed data. The dataset is analysed to ...

  12. Historical time trends in red blood cell usage in the Netherlands

    Directory of Open Access Journals (Sweden)

    van Hoeven LR

    2016-06-01

    Full Text Available Loan R van Hoeven,1,2 Maria MW Koopman,3 Hendrik Koffijberg,4 Kit CB Roes,1 Mart P Janssen1,2 1Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, 2Transfusion Technology Assessment Department, Sanquin Research, 3Department of Transfusion Medicine, Sanquin Blood Bank, Amsterdam, 4Department of Health Technology and Services Research, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, the Netherlands Background: While the number of hospitalized patients in Dutch hospitals has increased since 1997, the demand for red blood cell units (RBCs has simultaneously decreased. This implies a dramatic change in transfusion practice toward fewer blood transfusions on average per patient.Objectives: In order to explain the RBC reduction, different patient groups (surgical, medical, obstetrical, and specific age groups were studied retrospectively in relation to RBC use. In addition, the use of combinations of RBCs, fresh frozen plasma, and platelets during a transfusion episode was examined for trends over time.Materials and methods: Data from the PROTON database, containing information on all transfusions in twelve Dutch hospitals in the period 1996–2005, including corresponding patient data (age, diagnosis, treatment, and hospitalizations and blood unit data (type, amount, and date were analyzed.Results: The proportion of RBCs used for surgical patients declined from 50% in 1996 to 40% in 2005, whereas medical use increased from 47% to 58% (the remaining 2%–3% went to obstetrical patients. Changes were more marked in the higher age groups. Also, a trend was observed toward the use of only one or two RBCs during a transfusion episode rather than three or more. Among surgical patients who received blood, the use of combinations of blood units, as compared to RBCs only, increased from 32% to 39%.Conclusion: The results suggest a more restrictive transfusion policy

  13. New gridded daily climatology of Finland: Permutation-based uncertainty estimates and temporal trends in climate

    Science.gov (United States)

    Aalto, Juha; Pirinen, Pentti; Jylhä, Kirsti

    2016-04-01

    Long-term time series of key climate variables with a relevant spatiotemporal resolution are essential for environmental science. Moreover, such spatially continuous data, based on weather observations, are commonly used in, e.g., downscaling and bias correcting of climate model simulations. Here we conducted a comprehensive spatial interpolation scheme where seven climate variables (daily mean, maximum, and minimum surface air temperatures, daily precipitation sum, relative humidity, sea level air pressure, and snow depth) were interpolated over Finland at the spatial resolution of 10 × 10 km2. More precisely, (1) we produced daily gridded time series (FMI_ClimGrid) of the variables covering the period of 1961-2010, with a special focus on evaluation and permutation-based uncertainty estimates, and (2) we investigated temporal trends in the climate variables based on the gridded data. National climate station observations were supplemented by records from the surrounding countries, and kriging interpolation was applied to account for topography and water bodies. For daily precipitation sum and snow depth, a two-stage interpolation with a binary classifier was deployed for an accurate delineation of areas with no precipitation or snow. A robust cross-validation indicated a good agreement between the observed and interpolated values especially for the temperature variables and air pressure, although the effect of seasons was evident. Permutation-based analysis suggested increased uncertainty toward northern areas, thus identifying regions with suboptimal station density. Finally, several variables had a statistically significant trend indicating a clear but locally varying signal of climate change during the last five decades.

  14. Comparison of three vertically resolved ozone data bases: climatology, trends and radiative forcings

    Directory of Open Access Journals (Sweden)

    B. Hassler

    2012-10-01

    Full Text Available Climate models that do not simulate changes in stratospheric ozone concentrations require ozone input fields to accurately calculate UV fluxes and stratospheric heating rates. In this study, three different global ozone time series that are available for this purpose are compared: the data set of Randel and Wu (2007 (RW07, Cionni et al. (2011 (SPARC, and Bodeker et al. (2012 (BDBP. The latter is a very recent data set, based on the comprehensive ozone measurement database described by Hassler et al. (2008. All three data sets represent multiple-linear regression fits to vertically resolved ozone observations, resulting in a patially and temporally continuous stratospheric ozone field covering at least the period from 1979 to 2005. The main difference between the data sets result from using different observations and including different basis functions for the regression model fits. These three regression-based data sets are compared against observations from ozonesondes and satellites to compare how the data sets represent concentrations, trends, and interannual variability. In the Southern Hemisphere polar region, RW07 and SPARC underestimate the ozone depletion in spring as seen in ozonesonde measurements. A piecewise linear trend regression is performed to estimate the 1979–1996 ozone decrease globally, covering a period of extreme depletion in most regions. BDBP seems to overestimate Arctic and tropical ozone loss over this period somewhat relative to the available measurements, whereas these appear to be underestimated in RW07 and SPARC. In most regions, the three data sets yield ozone values that are within the range of the different observations that serve as input to the regressions. However, the differences among the three suggest that there are large uncertainties in ozone trends. These result in differences of almost a factor of four in radiative forcing, which is important for the resulting climate changes.

  15. Examining time trends in the Oldowan technology at Beds I and II, Olduvai Gorge.

    Science.gov (United States)

    Kimura, Yuki

    2002-09-01

    The lithic analysis of the Bed I and II assemblages from Olduvai Gorge reveals both static and dynamic time trends in early hominids' technology from 1.8 to 1.2 m.y.a. The Bed I Oldowan (1.87-1.75 m.y.a.) is characterized by the least effort strategy in terms of raw material exploitation and tool production. The inclusion of new raw material, chert, for toolmaking in the following Developed Oldowan A (DOA, 1.65-1.53 m.y.a.) facilitated more distinctive and variable flaking strategies depending on the kind of raw materials. The unique characters of DOA are explainable by this raw material factor, rather than technological development of hominids. The disappearance of chert in the subsequent Developed Oldowan B and Acheulian (1.53-1.2 m.y.a.) necessitated a shift in tool production strategy more similar to that of Bed I Oldowan than DOA. However, the evidence suggests that Bed II hominids might have been more skillful toolmakers, intensive tool-users, and engaged in more active transport of stone tools than the Bed I predecessors. Koobi Fora hominids maintained a more static tool-using behavior than their Olduvai counterparts due mainly to a stable supply of raw materials. They differed from Olduvai hominids in terms of less battering of cores, consistent transport behavior, and few productions of side-struck flakes, indicating a regional variation of toolmaking and using practice. However, they shared with Olduvai hominids a temporal trend toward the production of larger flakes from larger cores after 1.6 m.y.a. Increased intake of animal resources and the expansion of ranging area of Homo ergaster would have led to the development of technological organization. Technological changes in the Oldowan industry are attested at Olduvai Gorge, Koobi Fora, and Sterkfontein, suggesting that it was a pan-African synchronous phenomenon, beginning at 1.5 m.y.a. PMID:12234546

  16. Temporal trends in non-occupational sedentary behaviours from Australian Time Use Surveys 1992, 1997 and 2006

    Directory of Open Access Journals (Sweden)

    Chau Josephine Y

    2012-06-01

    Full Text Available Abstract Background Current epidemiological data highlight the potential detrimental associations between sedentary behaviours and health outcomes, yet little is known about temporal trends in adult sedentary time. This study used time use data to examine population trends in sedentary behaviours in non-occupational domains and more specifically during leisure time. Methods We conducted secondary analysis of population representative data from the Australian Time Use Surveys 1992, 1997 and 2006 involving respondents aged 20 years and over with completed time use diaries for two days. Weighted samples for each survey year were: n = 5851 (1992, n = 6419 (1997 and n = 5505 (2006. We recoded all primary activities by domain (sleep, occupational, transport, leisure, household, education and intensity (sedentary, light, moderate. Adjusted multiple linear regressions tested for differences in time spent in non-occupational sedentary behaviours in 1992 and 1997 with 2006 as the reference year. Results Total non-occupational sedentary time was slightly lower in 1997 than in 2006 (mean = 894 min/2d and 906 min/2d, respectively; B = −11.2; 95%CI: -21.5, -0.9. Compared with 2006, less time was spent in 1997 in sedentary transport (B-6.7; 95%CI: -10.4, -3.0 and sedentary education (B = −6.3; 95%CI: -10.5, -2.2 while household and leisure sedentary time remained stable. Time engaged in different types of leisure-time sedentary activities changed between 1997 and 2006: leisure-time computer use increased (B = −26.7; 95%CI: -29.5, -23.8, while other leisure-time sedentary behaviours (e.g., reading, listening to music, hobbies and crafts showed small concurrent reductions. In 1992, leisure screen time was lower than in 2006: TV-viewing (B = −24.2; 95%CI: -31.2, -17.2, computer use (B = −35.3; 95%CI: -37.7, -32.8. In 2006, 90 % of leisure time was spent sedentary, of which 53 % was screen time. Conclusions Non

  17. [Time trend study of firearm mortality in Argentina, 1980-2012].

    Science.gov (United States)

    Spinelli, Hugo; Santoro, Adrián; Guevel, Carlos; Alazraqui, Marcio

    2015-06-01

    This work analyzes the impact of firearm mortality between 1980 and 2012 in Argentina. For this purpose a descriptive epidemiological time trend study was carried out including the following variables: sex, age group, intentionality and jurisdiction. Data was obtained from the Office of Health Statistics and Information of the Argentine Ministry of Health. A total of 87,671 deaths due to firearms were discovered, of which 85.7% occurred in men. The highest mortality rate due to firearms corresponded to the year 2002, reaching 21.2 deaths per 100,000 inhabitants. The age group concentrating the largest number of deaths due to firearms was that of 20-29 years, accounting for 25.6% of all deaths. The highest adjusted rates corresponded to the years 2000-2002, with values of 10.0 to 11.6 deaths per 100,000 inhabitants. This time period coincides with the institutional-economic crisis the country experienced. The province of Buenos Aires was the place of residence of 49.1% of the deceased. In the discussion, political-economic and ideological-cultural dimensions of the relations among firearms, violence, science and society are considered.

  18. The Sentiment Trend Analysis of Twitter Based on Set Pair Contact Degree

    Directory of Open Access Journals (Sweden)

    Chunying Zhang

    2013-01-01

    Full Text Available Sentiment trend of twitter users have a great influence on their friends and the crowd listened. This paper directs at the user sentiment state of twitter, the unique medium, and applies set pair analysis method for trend analysis. First, we begin with set pair contact degree, then based on set pair affective computing model to make comparison with the size relationship of same degree, difference degree, opposition degree of the emotion, to build the user sentiment trend analysis model; Secondly, we analyze the influence for the user's own sentiment trend when the value changed of difference coefficient ; thirdly, after analyze to obtain one user's sentiment orientation threshold as prerequisite for user behavior prediction. Finally, setting an example to calculate the sentiment trend of one twitter, then to get the conclusion is that the analysis of user emotion from a three-dimensional angle is more realistic than the single angle.

  19. Whims of the Winds of Time? Emerging Trends in Biodiversity Conservation and Protected Area Management

    NARCIS (Netherlands)

    B.E. Büscher (Bram); W. Whande (Webster)

    2007-01-01

    textabstractThis article reviews narratives and trends in biodiversity conservation and protected area (PA) management and examines contestations within and among them in the light of developments within the global political economy. Its argument starts with the assumption that trends in biodiversit

  20. Contrasting time trends of organic contaminants in Antarctic pelagic and benthic food webs

    NARCIS (Netherlands)

    Brink, van den N.W.; Riddle, M.J.; Heuvel-Greve, van den M.J.; Franeker, van J.A.

    2011-01-01

    We demonstrate that pelagic Antarctic seabirds show significant decreases in concentrations of some persistent organic pollutants. Trends in Adélie penguins and Southern fulmars fit in a general pattern revealed by a broad literature review. Downward trends are also visible in pelagic fish, contrast

  1. An Effective Time Series Analysis for Stock Trend Prediction Using ARIMA Model for Nifty Midcap-50

    Directory of Open Access Journals (Sweden)

    B.Uma Devi

    2013-01-01

    Full Text Available The data mining and its tool has played a vital role in exploring the data from different ware houses. Using data mining tools and analytical technologies we do a quantifiable amount of research to explore new approach for the investment decisions .The market with huge volume of investor with good enough knowledge and have a prediction as well as control over their investments. The stock market some time fails to attract new investor. The reason states that non-aware and also people don’t want to come forward to fall in to the risk. An approach with adequate expertise is designed to help investors to ascertain veiled patterns from the historic data that have feasible predictive ability in their investment decisions. In this paper the NSE – Nifty Midcap50 companies among them top 4 companies having max Midcap value has been selected for analysis. The historical data has a significant role in, helping the investing people to get an overview about the market behavior during the past decade. The stock data for the past five years has been collected and trained using ARIMA model with different parameters. The test criterions like Akaike Information Criterion Bayesian Information Criterion (AICBIC are applied to predict the accuracy of the model. The performance of the trained model is analyzed and it also tested to find the trend and the market behavior for future forecast.

  2. Global Markets and Time-Based Competition

    OpenAIRE

    Elisa Rancati

    2005-01-01

    Time becomes the benchmark that defines a company's strategic behaviour, extensively revamping the entire company by reinterpreting the time dimension in a different, extremely dynamic context. Marketing activities always presuppose time-based competition. From a marketing perspective, oriented to analysis of the competition, time-based competition can be defined as a strategy based on immediate response to the customer's needs. In the competitive conditions of over-supply, the time dimension...

  3. Trends in Statin Use in Seniors 1999 to 2013: Time Series Analysis

    Science.gov (United States)

    Corkum, Amber; Sketris, Ingrid; Fisher, Judith; Zhang, Ying; Saleh, Ahmed

    2016-01-01

    Purpose To examine HMG-CoA reductase inhibitor (statin) drug dispensing patterns to Nova Scotia Seniors' Pharmacare program (NSSPP) beneficiaries over a 14-year period in response to: 1) rosuvastatin market entry in 2003, 2) JUPITER trial publication in 2008, and 3) generic atorvastatin availability in 2010. Methods All NSSPP beneficiaries who redeemed at least one prescription for a statin from April 1, 1999 to March 31, 2013 were included. Aggregated, anonymous monthly prescription counts were extracted by the Nova Scotia Department of Health and Wellness (Nova Scotia, Canada) and changes in dispensing patterns of statins were measured. Data were analyzed using descriptive analyses and interrupted time series methods. Results The percentage of NSSPP beneficiaries dispensed any statin increased from 5.3% in April 1999 to 20.7% in March 2013. In 1999, most NSSPP beneficiaries were dispensed either simvastatin (29.5%) or atorvastatin (28.7%). When rosuvastatin was added to the NSSPP Formulary in August 2003, prescriptions dispensed for simvastatin, lovastatin, pravastatin, and fluvastatin declined significantly (slope change, -0.0027; 95% confidence interval (CI), (-0.0046, -0.0009)). This significant decline continued following the publication of JUPITER (level change, -0.1974; 95% CI, (-0.2991, -0.0957)) and the availability of generic atorvastatin (level change, -0.2436; 95% CI, (-0.3314, -0.1558)). Atorvastatin was not significantly affected by any of the three interventions, although it maintained an overall decreasing trend. Only upon the availability of generic atorvastatin did the upward trend in rosuvastatin use decrease significantly (slope change, -0.0010, 95% CI, (-0.0015, -0.0005)). Conclusions The type and rate of statins dispensed to NSSPP beneficiaries changed from 1999 to 2013 in response to the availability of new agents and publication of the JUPITER trial. The overall proportion of NSSPP beneficiaries dispensed a statin increased approximately 4

  4. Trends in Statin Use in Seniors 1999 to 2013: Time Series Analysis.

    Directory of Open Access Journals (Sweden)

    Laura V Minard

    Full Text Available To examine HMG-CoA reductase inhibitor (statin drug dispensing patterns to Nova Scotia Seniors' Pharmacare program (NSSPP beneficiaries over a 14-year period in response to: 1 rosuvastatin market entry in 2003, 2 JUPITER trial publication in 2008, and 3 generic atorvastatin availability in 2010.All NSSPP beneficiaries who redeemed at least one prescription for a statin from April 1, 1999 to March 31, 2013 were included. Aggregated, anonymous monthly prescription counts were extracted by the Nova Scotia Department of Health and Wellness (Nova Scotia, Canada and changes in dispensing patterns of statins were measured. Data were analyzed using descriptive analyses and interrupted time series methods.The percentage of NSSPP beneficiaries dispensed any statin increased from 5.3% in April 1999 to 20.7% in March 2013. In 1999, most NSSPP beneficiaries were dispensed either simvastatin (29.5% or atorvastatin (28.7%. When rosuvastatin was added to the NSSPP Formulary in August 2003, prescriptions dispensed for simvastatin, lovastatin, pravastatin, and fluvastatin declined significantly (slope change, -0.0027; 95% confidence interval (CI, (-0.0046, -0.0009. This significant decline continued following the publication of JUPITER (level change, -0.1974; 95% CI, (-0.2991, -0.0957 and the availability of generic atorvastatin (level change, -0.2436; 95% CI, (-0.3314, -0.1558. Atorvastatin was not significantly affected by any of the three interventions, although it maintained an overall decreasing trend. Only upon the availability of generic atorvastatin did the upward trend in rosuvastatin use decrease significantly (slope change, -0.0010, 95% CI, (-0.0015, -0.0005.The type and rate of statins dispensed to NSSPP beneficiaries changed from 1999 to 2013 in response to the availability of new agents and publication of the JUPITER trial. The overall proportion of NSSPP beneficiaries dispensed a statin increased approximately 4-fold during the study period. In

  5. Time trends of cancer mortality among elderly in Italy, 1970–2008: an observational study

    Directory of Open Access Journals (Sweden)

    Bidoli Ettore

    2012-10-01

    Full Text Available Abstract Background The aging of the Italian population will unavoidably lead to a growing number of persons diagnosed and living with cancer. A comprehensive description of the burden of cancer mortality among Italian elderly (65-84 years of age in the last four decades has not been carried out yet. Cancer mortality rates were used to describe time trends between 1970-2008. Methods Mortality counts, provided by the Italian National Institute of Statistics, were grouped according to data availability: in quinquennia from 1970-74 through 1995-99, and in 2000-03 and 2006-08 groups. Age-standardized rates (world population were computed by calendar periods while annual percent changes (APCs were computed for elderly and middle aged (35-64 years people for the period 1995-2008. Results The number of cancer deaths in elderly nearly doubled between 1970-74 (31,400 deaths/year in men, and 24,000 in women and 2006-08 (63,000 deaths/year in men, and 42,000 in women. Overall cancer mortality rates peaked during the quinquennia 1985-89 and 1990-94 (about 1,500/100,000 in men and 680 in women and declined thereafter. Throughout 1995-2008 cancer mortality rates decreased by -1.6%/year in men and -0.9%/year in women. These decreases were mainly driven by cancers of the stomach, bladder, prostate, and lung (APC = -3.3%, -2.7%, -2.5%, -2.2%, respectively in men, and by cancers of the stomach, bladder, and breast (APC = -3.5%, -1.9%, -1.1%, respectively in women. Conversely, increases in mortality rates between 1995 and 2008 were recorded for lung cancer (APC = +0.6% in women, cutaneous melanoma (APC = +1.7% in men, and pancreatic cancer (APC = +0.6% in men and +0.9% in women. Conclusions Overall favorable trends in cancer mortality were observed among Italian elderly between 1995 and 2008. Early diagnosis, improved efficacy of anti-cancer treatments and management of comorbidities are the most likely explanations of these positive

  6. Groundwater level and nitrate concentration trends on Mountain Home Air Force Base, southwestern Idaho

    Science.gov (United States)

    Williams, Marshall L.

    2014-01-01

    Mountain Home Air Force Base in southwestern Idaho draws most of its drinking water from the regional aquifer. The base is located within the State of Idaho's Mountain Home Groundwater Management Area and is adjacent to the State's Cinder Cone Butte Critical Groundwater Area. Both areas were established by the Idaho Department of Water Resources in the early 1980s because of declining water levels in the regional aquifer. The base also is listed by the Idaho Department of Environmental Quality as a nitrate priority area. The U.S. Geological Survey, in cooperation with the U.S. Air Force, began monitoring wells on the base in 1985, and currently monitors 25 wells for water levels and 17 wells for water quality, primarily nutrients. This report provides a summary of water-level and nitrate concentration data collected primarily between 2001 and 2013 and examines trends in those data. A Regional Kendall Test was run to combine results from all wells to determine an overall regional trend in water level. Groundwater levels declined at an average rate of about 1.08 feet per year. Nitrate concentration trends show that 3 wells (18 percent) are increasing in nitrate concentration trend, 3 wells (18 percent) show a decreasing nitrate concentration trend, and 11 wells (64 percent) show no nitrate concentration trend. Six wells (35 percent) currently exceed the U.S. Environmental Protection Agency's maximum contaminant limit of 10 milligrams per liter for nitrate (nitrite plus nitrate, measured as nitrogen).

  7. A sensitivity analysis of secular trends in risk factors and mortality based on cohort studies

    DEFF Research Database (Denmark)

    Prescott, E; Andersen, P K; Osler, M;

    1999-01-01

    biased. In a sensitivity analysis, the observed person-years of nonresponders were distributed among six categories of persons with respect to smoking behavior (never-smokers; ex-smokers; noninhaling current smokers; and current smokers of 1-14, 15-24, and > or =25 gm tobacco per day) according to preset...... secular trend in mortality. By applying different assumptions regarding smoking habits among nonresponders, we explored the effect of the assumptions on the adjusted secular trend in mortality. We conclude that secular trends in mortality based on responders in a cohort study are likely to be biased...

  8. Pulmonary tuberculosis space-time clustering and spatial variation in temporal trends in Portugal, 2000-2010: an updated analysis.

    Science.gov (United States)

    Areias, C; Briz, T; Nunes, C

    2015-11-01

    Portugal, a medium- to low-level endemic country (21·6 cases/100 000 population in 2012), has one of the highest European Union tuberculosis (TB) incidences. Although incidence is declining progressively, the country's heterogeneity in both regional endemics and their evolution suggests the importance of a better understanding of subnational epidemiology to customize TB control efforts. We aimed to update knowledge on municipality-years pulmonary TB incidence clustering, identify areas with different time trends, and show the potential of combining complementary clustering methods in control of infectious diseases. We used national surveillance municipality-level data (mainland Portugal, 2000-2010). Space-time clustering and spatial variation in temporal trends methods were applied. Space-time critical clusters identified (P < 0·001) were still the Lisbon and Oporto regions. The global incidence declined at a 5·81% mean annual percentage change, with high space-time heterogeneity and distinct time trend clusters (P < 0·001). Municipalities with incidences declining more rapidly belonged to critical areas. In particular, the Oporto trend cluster had a consistent -8·98% mean annual percentage change. Large space-time heterogeneities were identified, with critical incidences in the greater Lisbon and Oporto regions, but declining more rapidly in these regions. Oporto showed a consistent, steeper decrease and could represent a good example of local control strategy. Combining results from these approaches gives promise for prospects for infectious disease control and the design of more effective, focused interventions.

  9. Time Trends in Total Ankle Arthroplasty in the U.S.: A Study of the Nationwide Inpatient Sample

    Science.gov (United States)

    Singh, Jasvinder A.; Ramachandaran, Rekha

    2014-01-01

    Objective To assess the time-trends in utilization, clinical characteristics and outcomes of patients undergoing total ankle arthroplasty (TAA) in the U.S. Methods We used the Nationwide Inpatient Sample (NIS) data from 1998 to 2010 to examine time-trends in the utilization rates of TAA. We used the Cochran Armitage test for trend to assess time-trends across the years and the analysis of variance (ANOVA), Wilcoxon test or chi-squared test (as appropriate) to compare the first (1998–2000) and the last time periods (2009–10). Results TAA utilization rate increased significant from 1998 to 2010: 0.13 to 0.84 per 100,000 overall, 0.14 to 0.88 per 100,000 in females and from 0.11 to 0.81 per 100,000 in males (p0.05). Conclusions The utilization rate of TAA increased rapidly in the U.S. from 1998 to 2010, but post-arthroplasty mortality rate was stable. Underlying diagnosis and medical comorbidity changed over time and both can impact outcomes after TAA. Further studies should examine how the outcomes and complications of TAA have evolved over time. PMID:24907036

  10. De-trending of wind speed variance based on first-order and second-order statistical moments only

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Hansen, Kurt Schaldemose

    2014-01-01

    The lack of efficient methods for de-trending of wind speed resource data may lead to erroneous wind turbine fatigue and ultimate load predictions. The present paper presents two models, which quantify the effect of an assumed linear trend on wind speed standard deviations as based on available...... statistical data only. The first model is a pure time series analysis approach, which quantifies the effect of non-stationary characteristics of ensemble mean wind speeds on the estimated wind speed standard deviations as based on mean wind speed statistics only. This model is applicable to statistics...... of arbitrary types of time series. The second model uses the full set of information and includes thus additionally observed wind speed standard deviations to estimate the effect of ensemble mean non-stationarities on wind speed standard deviations. This model takes advantage of a simple physical relationship...

  11. Comparison of two regression-based approaches for determining nutrient and sediment fluxes and trends in the Chesapeake Bay watershed

    Science.gov (United States)

    Moyer, Douglas; Hirsch, Robert M.; Hyer, Kenneth

    2012-01-01

    Nutrient and sediment fluxes and changes in fluxes over time are key indicators that water resource managers can use to assess the progress being made in improving the structure and function of the Chesapeake Bay ecosystem. The U.S. Geological Survey collects annual nutrient (nitrogen and phosphorus) and sediment flux data and computes trends that describe the extent to which water-quality conditions are changing within the major Chesapeake Bay tributaries. Two regression-based approaches were compared for estimating annual nutrient and sediment fluxes and for characterizing how these annual fluxes are changing over time. The two regression models compared are the traditionally used ESTIMATOR and the newly developed Weighted Regression on Time, Discharge, and Season (WRTDS). The model comparison focused on answering three questions: (1) What are the differences between the functional form and construction of each model? (2) Which model produces estimates of flux with the greatest accuracy and least amount of bias? (3) How different would the historical estimates of annual flux be if WRTDS had been used instead of ESTIMATOR? One additional point of comparison between the two models is how each model determines trends in annual flux once the year-to-year variations in discharge have been determined. All comparisons were made using total nitrogen, nitrate, total phosphorus, orthophosphorus, and suspended-sediment concentration data collected at the nine U.S. Geological Survey River Input Monitoring stations located on the Susquehanna, Potomac, James, Rappahannock, Appomattox, Pamunkey, Mattaponi, Patuxent, and Choptank Rivers in the Chesapeake Bay watershed. Two model characteristics that uniquely distinguish ESTIMATOR and WRTDS are the fundamental model form and the determination of model coefficients. ESTIMATOR and WRTDS both predict water-quality constituent concentration by developing a linear relation between the natural logarithm of observed constituent

  12. Contrasting time trends of organic contaminants in Antarctic pelagic and benthic food webs.

    Science.gov (United States)

    van den Brink, Nico W; Riddle, Martin J; van den Heuvel-Greve, Martine; van Franeker, Jan Andries

    2011-01-01

    We demonstrate that pelagic Antarctic seabirds show significant decreases in concentrations of some persistent organic pollutants. Trends in Adélie penguins and Southern fulmars fit in a general pattern revealed by a broad literature review. Downward trends are also visible in pelagic fish, contrasting sharply with steady or increasing concentrations in Antarctic benthic organisms. Transfer of contaminants between Antarctic pelagic and benthic food webs is associated with seasonal sea-ice dynamics which may influence the balance between the final receptors of contaminants under different climatic conditions. This complicates the predictability of future trends of emerging compounds in the Antarctic ecosystem, such as of the brominated compounds that we detected in Antarctic petrels. The discrepancy in trends between pelagic and benthic organisms shows that Antarctic biota are still final receptors of globally released organic contaminants and it remains questionable whether the total environmental burden of contaminants in the Antarctic ecosystem is declining.

  13. Using earth observation-based dry season NDVI trends for assessment of changes in tree cover in the Sahel

    DEFF Research Database (Denmark)

    Horion, Stéphanie Marie Anne F; Fensholt, Rasmus; Tagesson, Håkan Torbern;

    2014-01-01

    as a proxy for tree cover in the Sahel, two factors that could potentially influence dry season NDVImin estimates were analysed: the total biomass accumulated during the preceding growing season and the percentage of burned area observed during the dry season. Time series of dry season NDVImin derived from...... low-resolution satellite time series were found to be uncorrelated to dry grass residues from the preceding growing season and to seasonal fire frequency and timing over most of the Sahel (88%), suggesting that NDVImin can serve as a proxy for assessing changes in tree cover. Good agreement (R2= 0.......79) between significant NDVImin trends (ptime series over the Western Sahel, whereas trends based on GIMMS data were negative for the greater part of the Sahel. EO...

  14. Ontology Based Document Annotation: Trends and Open Research Problems

    OpenAIRE

    Corcho, Oscar

    2006-01-01

    Metadata is used to describe documents and applications, improving information seeking and retrieval and its understanding and use. Metadata can be expressed in a wide variety of vocabularies and languages, and can be created and maintained with a variety of tools. Ontology based annotation refers to the process of creating metadata using ontologies as their vocabularies. We present similarities and differences with respect to other approaches for metadata creation, and describe languages and...

  15. Mindfulness-based cognitive therapy for depression: trends and developments

    OpenAIRE

    MacKenzie MB; Kocovski NL

    2016-01-01

    Meagan B MacKenzie,1 Nancy L Kocovski21Department of Psychology, Ryerson University, Toronto, ON, Canada; 2Department of Psychology, Wilfrid Laurier University, Waterloo, ON, CanadaAbstract: Mindfulness-based cognitive therapy (MBCT) was developed as a psychological intervention for individuals at risk of depressive relapse. Possible mechanisms of change for this intervention are in line with its theoretical underpinnings, and include increases in mindfulness and/or decreases in nega...

  16. Future Trends in Reliability-Based Bridge Management

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Future bridge management systems will be based on simple stochastic models predicting the residual strength of structural elements. The current deterministic management systems are not effective in optimizing e.g. the life cycle cost of a bridge or a system of bridges. A number of important facto...... are so uncertain that they cannot be modelled satisfactorily by deterministic techniques. In recent years several researchers have studied stochastic modelling of e.g. deterioration, inspection, reliability, and repair but real applications are only reported in a few cases....

  17. Did FDA Decisionmaking Affect Anti-Psychotic Drug Prescribing in Children?: A Time-Trend Analysis.

    Directory of Open Access Journals (Sweden)

    Bo Wang

    Full Text Available Following Food and Drug Administration (FDA approval, many drugs are prescribed for non-FDA-approved ("off-label" uses. If substantial evidence supports the efficacy and safety of off-label indications, manufacturers can pursue formal FDA approval through supplemental new drug applications (sNDAs. We evaluated the effect of FDA determinations on pediatric sNDAs for antipsychotic drugs on prescribing of these products in children.Retrospective, segmented time-series analysis using new prescription claims during 2003-2012 for three atypical antipsychotics (olanzapine, quetiapine, ziprasidone. FDA approved the sNDAs for pediatric use of olanzapine and quetiapine in December 2009, but did not approve the sNDA for pediatric use of ziprasidone.During the months before FDA approval of its pediatric sNDA, new prescriptions of olanzapine decreased for both children and adults. After FDA approval, the increase in prescribing trends was similar for both age groups (P = 0.47 for schizophrenia and bipolar disorder; P = 0.37 for other indications. Comparable decreases in use of quetiapine were observed between pediatrics and adults following FDA approval of its pediatric sNDA (P = 0.88; P = 0.63. Prescribing of ziprasidone decreased similarly for pediatric and adult patients after FDA non-approval of its pediatric sNDA (P = 0.61; P = 0.79.The FDA's sNDA determinations relating to use of antipsychotics in children did not result in changes in use that favored the approved sNDAs and disfavored the unapproved sNDA. Improved communication may help translate the agency's expert judgments to clinical practice.

  18. New Trends in Agent-Based Complex Automated Negotiations

    CERN Document Server

    Zhang, Minjie; Robu, Valentin; Fatima, Shaheen; Matsuo, Tokuro

    2012-01-01

    Complex Automated Negotiations represent an important, emerging area in the field of Autonomous Agents and Multi-Agent Systems. Automated negotiations can be complex, since there are a lot of factors that characterize such negotiations. These factors include the number of issues, dependencies between these issues,  representation of utilities, the negotiation protocol, the number of parties in the negotiation (bilateral or multi-party), time constraints, etc. Software agents can support automation or simulation of such complex negotiations on the behalf of their owners, and can provide them with efficient bargaining strategies. To realize such a complex automated negotiation, we have to incorporate advanced Artificial Intelligence technologies includes search, CSP, graphical utility models, Bayes nets, auctions, utility graphs, predicting and learning methods. Applications could include e-commerce tools, decision-making support tools, negotiation support tools, collaboration tools, etc. This book aims to pro...

  19. Assessment of land degradation using time series trend analysis of vegetation indictors in Otindag Sandy land

    International Nuclear Information System (INIS)

    Land condition assessment is a basic prerequisite for finding the degradation of a territory, which might lead to desertification under climatic and human pressures. The temporal change in vegetation productivity is a key indicator of land degradation. In this paper, taking the Otindag Sandy Land as a case, the mean normalized difference vegetation index (NDVIa), net primary production (NPP) and vegetation rain use efficiency (RUE) dynamic trends during 2001–2010 were analysed. The Mann-Kendall test and the Correlation Analysis method were used and their sensitivities to land degradation were evaluated. The results showed that the three vegetation indicators (NDVIa, NPP and RUE) showed a downward trend with the two methods in the past 10 years and the land was degraded. For the analysis of the three vegetation indicators (NDVIa, NPP and RUE), it indicated a decreasing trend in 62.57%, 74.16% and 88.56% of the study area according to the Mann-Kendall test and in 57.85%, 68.38% and 85.29% according to the correlation analysis method. However, the change trends were not significant, the significant trends at the 95% confidence level only accounted for a small proportion. Analysis of NDVIa, NPP and RUE series showed a significant decreasing trend in 9.21%, 4.81% and 6.51% with the Mann-Kendall test. The NPP change trends showed obvious positive link with the precipitation in the study area. While the effect of the inter-annual variation of the precipitation for RUE was small, the vegetation RUE can provide valuable insights into the status of land condition and had best sensitivity to land degradation

  20. Multi-annual changes of NOx emissions in megacity regions: nonlinear trend analysis of satellite measurement based estimates

    Directory of Open Access Journals (Sweden)

    J. P. Burrows

    2010-04-01

    Full Text Available Hazardous impact of air pollutant emissions from megacities on atmospheric composition on regional and global scales is currently an important issue in atmospheric research. However, the quantification of emissions and related effects is frequently a difficult task, especially in the case of developing countries, due to the lack of reliable data and information. This study examines possibilities to retrieve multi-annual NOx emissions changes in megacity regions from satellite measurements of nitrogen dioxide and to quantify them in terms of linear and nonlinear trends. By combining the retrievals of the GOME and SCIAMACHY satellite instrument data with simulations performed by the CHIMERE chemistry transport model, we obtain the time series of NOx emission estimates for the 12 largest urban agglomerations in Europe and the Middle East in the period from 1996 to 2008. We employ then a novel method allowing estimation of a nonlinear trend in a noisy time series of an observed variable. The method is based on the probabilistic approach and the use of artificial neural networks; it does not involve any quantitative a priori assumptions. As a result, statistically significant nonlinearities in the estimated NOx emission trends are detected in 5 megacities (Bagdad, Madrid, Milan, Moscow and Paris. Statistically significant upward linear trends are detected in Istanbul and Tehran, while downward linear trends are revealed in Berlin, London and the Ruhr agglomeration. The presence of nonlinearities in NOx emission changes in Milan, Paris and Madrid is confirmed by comparison of simulated NOx concentrations with independent air quality monitoring data. A good quantitative agreement between the linear trends in the simulated and measured near surface NOx concentrations is found in London.

  1. Multi-annual changes of NOx emissions in megacity regions: nonlinear trend analysis of satellite measurement based estimates

    Directory of Open Access Journals (Sweden)

    J. P. Burrows

    2010-09-01

    Full Text Available Hazardous impact of air pollutant emissions from megacities on atmospheric composition on regional and global scales is currently an important issue in atmospheric research. However, the quantification of emissions and related effects is frequently a difficult task, especially in the case of developing countries, due to the lack of reliable data and information. This study examines possibilities to retrieve multi-annual NOx emissions changes in megacity regions from satellite measurements of nitrogen dioxide and to quantify them in terms of linear and nonlinear trends. By combining the retrievals of the GOME and SCIAMACHY satellite instrument data with simulations performed by the CHIMERE chemistry transport model, we obtain the time series of NOx emission estimates for the 12 largest urban agglomerations in Europe and the Middle East in the period from 1996 to 2008. We employ then a novel method allowing estimation of a nonlinear trend in a noisy time series of an observed variable. The method is based on the probabilistic approach and the use of artificial neural networks; it does not involve any quantitative a priori assumptions. As a result, statistically significant nonlinearities in the estimated NOx emission trends are detected in 5 megacities (Bagdad, Madrid, Milan, Moscow and Paris. Statistically significant upward linear trends are detected in Istanbul and Tehran, while downward linear trends are revealed in Berlin, London and the Ruhr agglomeration. The presence of nonlinearities in NOx emission changes in Milan, Paris and Madrid is confirmed by comparison of simulated NOx concentrations with independent air quality monitoring data. A good quantitative agreement between the linear trends in the simulated and measured near surface NOx concentrations is found in London.

  2. Current Trends in Nanomaterial-Based Amperometric Biosensors

    Directory of Open Access Journals (Sweden)

    Akhtar Hayat

    2014-12-01

    Full Text Available The last decade has witnessed an intensive research effort in the field of electrochemical sensors, with a particular focus on the design of amperometric biosensors for diverse analytical applications. In this context, nanomaterial integration in the construction of amperometric biosensors may constitute one of the most exciting approaches. The attractive properties of nanomaterials have paved the way for the design of a wide variety of biosensors based on various electrochemical detection methods to enhance the analytical characteristics. However, most of these nanostructured materials are not explored in the design of amperometric biosensors. This review aims to provide insight into the diverse properties of nanomaterials that can be possibly explored in the construction of amperometric biosensors.

  3. Levels, fluxes and time trends of persistent organic pollutants in Lake Thun, Switzerland: Combining trace analysis and multimedia modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bogdal, Christian [Institute for Chemical and Bioengineering, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zuerich (Switzerland); Empa, Swiss Federal Laboratories for Materials Testing and Research, Uberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Scheringer, Martin, E-mail: scheringer@chem.ethz.ch [Institute for Chemical and Bioengineering, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zuerich (Switzerland); Schmid, Peter [Empa, Swiss Federal Laboratories for Materials Testing and Research, Uberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Blaeuenstein, Markus [Institute for Chemical and Bioengineering, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zuerich (Switzerland); Kohler, Martin [State Food Law Enforcement Authority, Werkhofstrasse 5, CH-4509 Solothurn (Switzerland); Hungerbuehler, Konrad [Institute for Chemical and Bioengineering, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zuerich (Switzerland)

    2010-08-01

    Levels, mass fluxes, and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Lake Thun, a peri-Alpine lake, are investigated. We present measurements of PBDEs and PCBs in air, lake water, lake sediment, and tributary water. These measurements are combined with a multimedia fate model, based on site-specific environmental parameters from the lake catchment. Measured loadings of PBDEs and PCBs in air and tributaries were used to drive the model. The model satisfactorily reproduces PBDE and PCB congener patterns in water and sediment, but it tends to yield concentrations in water below the measurements and concentrations in sediment exceeding the measurements. A sensitivity analysis reveals that partitioning of PBDEs and PCBs between the aqueous dissolved phase and suspended particulate matter in the water column strongly affects the model results, in particular the concentrations in water and sediment. For lower-brominated PBDEs, approximately 70% and 30% of input into the lake stems from atmospheric deposition and from tributaries, respectively. For heavier PBDEs and all PCBs, rivers appear to deliver the major load (64-92%). Waste water effluents are of minor importance. 50-90% of the total input is buried in the permanent sediment. Sediment burial makes PBDEs and PCBs less available for recycling in the environment, and reduces concentrations in the outflowing river. If use of deca-BDE increases in the future, levels in Lake Thun will follow the same trend. If the use and resulting environmental emissions decrease, concentrations in water will rapidly decline, according to our calculations, while sediment levels will decrease at a considerably slower rate.

  4. Levels, fluxes and time trends of persistent organic pollutants in Lake Thun, Switzerland: Combining trace analysis and multimedia modeling

    International Nuclear Information System (INIS)

    Levels, mass fluxes, and time trends of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Lake Thun, a peri-Alpine lake, are investigated. We present measurements of PBDEs and PCBs in air, lake water, lake sediment, and tributary water. These measurements are combined with a multimedia fate model, based on site-specific environmental parameters from the lake catchment. Measured loadings of PBDEs and PCBs in air and tributaries were used to drive the model. The model satisfactorily reproduces PBDE and PCB congener patterns in water and sediment, but it tends to yield concentrations in water below the measurements and concentrations in sediment exceeding the measurements. A sensitivity analysis reveals that partitioning of PBDEs and PCBs between the aqueous dissolved phase and suspended particulate matter in the water column strongly affects the model results, in particular the concentrations in water and sediment. For lower-brominated PBDEs, approximately 70% and 30% of input into the lake stems from atmospheric deposition and from tributaries, respectively. For heavier PBDEs and all PCBs, rivers appear to deliver the major load (64-92%). Waste water effluents are of minor importance. 50-90% of the total input is buried in the permanent sediment. Sediment burial makes PBDEs and PCBs less available for recycling in the environment, and reduces concentrations in the outflowing river. If use of deca-BDE increases in the future, levels in Lake Thun will follow the same trend. If the use and resulting environmental emissions decrease, concentrations in water will rapidly decline, according to our calculations, while sediment levels will decrease at a considerably slower rate.

  5. Secular trends and seasonality in first-time hospitalization for acute myocardial infarction

    DEFF Research Database (Denmark)

    Fischer, Thomas; Lundbye-Christensen, Søren; Johnsen, Søren Paaske;

    2004-01-01

    The incidence of acute myocardial infarction has declined in several Western countries during the last decades. The incidence and mortality of acute myocardial infarction follow a seasonal pattern. We examined if changes in the incidence of acute myocardial infarction were associated with any...... changes in seasonality. Methods: The study was based on 17,989 patients hospitalized with first-time acute myocardial infarction identified in the Hospital Discharge Registry of the County of North Jutland, Denmark, from 1 January 1983 to 31 December 1999. The seasonality of acute myocardial infarction...... of these seasonal patterns remained stable throughout the study period despite the decline in hospitalizations for acute myocardial infarction. Conclusion> Hospitalizations for first-time acute myocardial infarction decreased from 1983 to 1999, but the seasonal pattern remained stable over time....

  6. Time trend in access to the waiting list and renal transplantation: a comparison of four European countries.

    NARCIS (Netherlands)

    Stel, V.S.; Kramar, R.; Leivestad, T.; Hoitsma, A.J.; Metcalfe, W.; Smits, J.M.M.; Ravani, P.; Jager, K.J.

    2012-01-01

    Background To examine the time trend and international differences in access to the waiting list and renal transplantation of patients with end-stage kidney disease. Methods We included all patients (n = 30 961) from Austria, Norway, the Netherlands and Scotland who started renal replacement therapy

  7. Dialysis-requiring acute kidney injury in Denmark 2000-2012: time trends of incidence and prevalence of risk factors

    DEFF Research Database (Denmark)

    Carlson, Nicholas; Hommel, Kristine; Olesen, Jonas Bjerring;

    2016-01-01

    INTRODUCTION: Dialysis-requiring acute kidney injury is a severe illness associated with poor prognosis. However, information pertaining to incidence rates and prevalence of risk factors remains limited in spite of increasing focus. We evaluate time trends of incidence rates and changing patterns...

  8. Modelling Patterns of Improvement over Time: Value Added Trends in English Secondary School Performance across Ten Cohorts

    Science.gov (United States)

    Thomas, Sally; Peng, Wen Jung; Gray, John

    2007-01-01

    This paper looks at underlying patterns of school effectiveness through analysing a GCSE examination data-set over a period of ten cohorts (1993-2002) in one very large English school district. Both value added and raw score approaches were explored by employing different statistical multilevel models to examine time trends of school and pupil…

  9. The Ireland of Asia: trends in marriage timing in Sri Lanka.

    Science.gov (United States)

    De Silva, W I

    1997-06-01

    This study examines marriage patterns among ever married women in Sri Lanka. Data are obtained from the 1987 and 1993 Sri Lanka Demographic and Health Surveys and population censuses during 1946-81. The greatest change in marriage patterns in Sri Lanka is the shift from arranged marriages to individual choice of partners. The individual attributes of the nuclear family have replaced household attributes, such the primacy of the family and hard work. Increased educational levels are desired for a marriage partner. Premarital sex behavior resulted in premarital first births among 1 in 6 married women 20-24 years old at the time of the survey. The singulate mean age of marriage increased from 18.3 years to 25.1 years during 1901-75, which means a long exposure to potential sexual activity. During 1975-80, SMAM has declined for both sexes, and then increased by 1 year. Rates of divorce and widowhood were quite low. The proportion of never married steadily increased over the decades. During 1946-93, the proportion of never married among women 15-19 years old increased from 75% to 93%. Among women 20-24 years old, the proportion increased from 29% to 61%. Marriage timing patterns in Sri Lanka are dissimilar to other South Asian countries and similar to Ireland's patterns. The age at first marriage increased from 20.8 years in the oldest cohort to 24.3 years in the cohort 35-39 years old. Cohorts younger than 35 years show a declining trend in marriage age. It is argued that marriage was delayed during the mid-1970s due to dowry, housing, and wedding expenses. Late marriage was due to the marriage squeeze and socioeconomic change. Mortality declined during the anti-malarial campaign of the late 1940s, with the result that more females were born during 1947-51 than males were born during 1942-46. First marriage ages range from 15 to 29 years for females and from 20 to 34 years for males.

  10. Analysis of stratospheric NO2 trends above Jungfraujoch using ground-based UV-visible, FTIR, and satellite nadir observations

    Directory of Open Access Journals (Sweden)

    R. Stübi

    2012-09-01

    Full Text Available The trend in stratospheric NO2 column at the NDACC (Network for the Detection of Atmospheric Composition Change station of Jungfraujoch (46.5° N, 8.0° E is assessed using ground-based FTIR and zenith-scattered visible sunlight SAOZ measurements over the period 1990 to 2009 as well as a composite satellite nadir data set constructed from ERS-2/GOME, ENVISAT/SCIAMACHY, and METOP-A/GOME-2 observations over the 1996–2009 period. To calculate the trends, a linear least squares regression model including explanatory variables for a linear trend, the mean annual cycle, the quasi-biennial oscillation (QBO, solar activity, and stratospheric aerosol loading is used. For the 1990–2009 period, statistically indistinguishable trends of −3.7 ± 1.1% decade−1 and −3.6 ± 0.9% decade−1 are derived for the SAOZ and FTIR NO2 column time series, respectively. SAOZ, FTIR, and satellite nadir data sets show a similar decrease over the 1996–2009 period, with trends of −2.4 ± 1.1% decade−1, −4.3 ± 1.4% decade−1, and −3.6 ± 2.2% decade−1, respectively. The fact that these declines are opposite in sign to the globally observed +2.5% decade−1 trend in N2O, suggests that factors other than N2O are driving the evolution of stratospheric NO2 at northern mid-latitudes. Possible causes of the decrease in stratospheric NO2 columns have been investigated. The most likely cause is a change in the NO2/NO partitioning in favor of NO, due to a possible stratospheric cooling and a decrease in stratospheric chlorine content, the latter being further confirmed by the negative trend in the ClONO2 column derived from FTIR observations at Jungfraujoch. Decreasing ClO concentrations slows the NO + ClO → NO2 + Cl reaction and a stratospheric cooling slows the NO + O3 → NO2 + O2 reaction, leaving more NOx in the form of NO. The slightly positive trends in ozone estimated from ground- and satellite-based data sets are also consistent with the decrease of

  11. Trends in web-based HIV behavioural surveillance among gay and bisexual men in New Zealand: complementing location-based surveillance.

    Science.gov (United States)

    Saxton, Peter J W; Dickson, Nigel P; Hughes, Anthony J

    2015-01-01

    Most HIV behavioural surveillance programmes for gay, bisexual and other men who have sex with men (MSM) sample from location-based (offline) or web-based (online) populations, but few combine these two streams. MSM sampled online have been found to differ demographically and behaviourally from those sampled offline, meaning trends identified in one system may not hold for the other. The aim was to examine trends among MSM responding to supplementary repeat online behavioural surveillance surveys who had not participated in offline surveillance earlier that year in the same city, to see whether trends were parallel, converged or diverged. We recruited a total of 1613 MSM from an Internet dating site in Auckland, New Zealand in 2006, 2008 and 2011 using identical questionnaires and eligibility criteria to offline surveillance. Condom use was stable over time, HIV testing rates rose, the proportion reporting over 20 recent male partners declined, and anal intercourse rates increased, consistent with trends in offline surveillance conducted concomitantly and reported elsewhere. Variant trends included greater stability in condom use with casual partners among online-recruited MSM, and a rise in regular fuckbuddy partnering not identified among offline-recruited MSM. Among MSM recruited online, the frequency of checking Internet dating profiles increased between 2008 and 2011. In conclusion, supplementary web-based behavioural surveillance among MSM generally corroborates trends identified in offline surveillance. There are however some divergent trends, that would have been overlooked if only one form of surveillance had been conducted. As MSM populations increasingly shift their socialising patterns online and diversify, multiple forms of HIV behavioural monitoring may be required. PMID:25599259

  12. Aircraft emission inventories for scheduled air traffic for the 1976-92 time period. Historical trends

    Energy Technology Data Exchange (ETDEWEB)

    Baughcum, S.L.; Henderson, S.C.; Tritz, T.G. [Boeing Co., Seattle, WA (United States)

    1997-12-31

    Emission inventories of fuel burned, NO{sub x}, CO, and hydrocarbons have been calculated for scheduled air traffic in 1976, 1984, 1990 and 1992 on a 1 deg latitude x 1 deg longitude x 1 km pressure altitude grid. Using this database, the seasonal variation and historical trends in aircraft emissions have been calculated for selected geographical regions (e.g., North Atlantic, Europe, North America, North Pacific). The trend in emissions is a combination of the effects of passenger demand growth, improved aircraft efficiency, changes in combustor characteristics, and aircraft size. (author) 8 refs.

  13. Agenda Trending: Reciprocity and the Predictive Capacity of Social Networking Sites in Intermedia Agenda Setting across Topics over Time

    OpenAIRE

    Jacob Groshek; Megan Clough Groshek

    2013-01-01

    In the contemporary converged media environment, agenda setting is being transformed by the dramatic growth of audiences that are simultaneously media users and producers. The study reported here addresses related gaps in the literature by first comparing the topical agendas of two leading traditional media outlets (New York Times and CNN) with the most frequently shared stories and trending topics on two widely popular Social Networking Sites (Facebook and Twitter). Time-series analyses of t...

  14. Adaptive Wavelets Based on Second Generation Wavelet Transform and Their Applications to Trend Analysis and Prediction

    Institute of Scientific and Technical Information of China (English)

    DUAN Chen-dong; JIANG Hong-kai; HE Zheng-jia

    2004-01-01

    In order to make trend analysis and prediction to acquisition data in a mechanical equipment condition monitoring system, a new method of trend feature extraction and prediction of acquisition data is proposed which constructs an adaptive wavelet on the acquisition data by means of second generation wavelet transform (SGWT). Firstly, taking the vanishing moment number of the predictor as a constraint, the linear predictor and updater are designed according to the acquisition data by using symmetrical interpolating scheme. Then the trend of the data is obtained through doing SGWT decomposition, threshold processing and SGWT reconstruction. Secondly, under the constraint of the vanishing moment number of the predictor, another predictor based on the acquisition data is devised to predict the future trend of the data using a non-symmetrical interpolating scheme. A one-step prediction algorithm is presented to predict the future evolution trend with historical data. The proposed method obtained a desirable effect in peak-to-peak value trend analysis for a machine set in an oil refinery.

  15. Obesity prevalence and time trend among youngsters in China, 1982-2002

    NARCIS (Netherlands)

    Li, Y.P.; Schouten, E.G.; Hu, X.Q.; Cui, Z.H.; Luan, D.C.; Guansheng Ma,

    2008-01-01

    Purpose of present study is to describe the prevalence and trend of overweight and obesity, as well as its coexistence with stunting, among youngsters in China, from 1982 to 2002. Data from children 7-17 years of age from three cross-sectional national surveys: 1982 China National Nutrition Survey (

  16. Time trends in educational inequalities in cancer mortality in Colombia, 1998-2012

    NARCIS (Netherlands)

    E. de Vries (Esther); I. Arroyave (Ivan); C. Pardo (Constanza)

    2016-01-01

    textabstractObjectives: To evaluate trends in premature cancer mortality in Colombia by educational level in three periods: 1998-2002 with low healthcare insurance coverage, 2003-2007 with rapidly increasing coverage and finally 2008-2012 with almost universal coverage (2008-2012). Setting: Colombia

  17. 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.

  18. Historical Trends in Ground-Based Optical Space Surveillance System Design

    Science.gov (United States)

    Shoemaker, M.; Shroyer, L.

    In the spirit of the 50th anniversary of the launch of the first man-made satellite, an historical overview of ground-based optical space surveillance systems is provided. Specific emphasis is given on gathering metrics to analyze design trends. The subject of space surveillance spans the history of spaceflight: from the early tracking cameras at missile ranges, the first observations of Sputnik, to the evolution towards highly capable commercial off-the-shelf (COTS) systems, and much in between. Whereas previous reviews in the literature have been limited in scope to specific time periods, operational programs, countries, etc., a broad overview of a wide range of sources is presented. This review is focused on systems whose primary design purpose can be classified as Space Object Identification (SOI) or Orbit Determination (OD). SOI systems are those that capture images or data to determine information about the satellite itself, such as attitude, features, and material composition. OD systems are those that produce estimates of the satellite position, usually in the form of orbital elements or a time history of tracking angles. Systems are also categorized based on the orbital regime in which their targets reside, which has been simplified in this study to either Low Earth Orbit (LEO) or Geosynchronous Earth Orbit (GEO). The systems are further classified depending on the industry segment (government/commercial or academic), and whether the program is foreign or domestic. In addition to gathering metrics on systems designed solely for man-made satellite observations, it is interesting to find examples of other systems being similarly used. Examples include large astronomical telescopes being used for GEO debris surveys and anomaly resolution for deep-space probes. Another interesting development is the increase in number and capability of COTS systems, some of which are specifically marketed to consumers as satellite trackers. After describing the results of the

  19. Infodemiology of status epilepticus: A systematic validation of the Google Trends-based search queries.

    Science.gov (United States)

    Bragazzi, Nicola Luigi; Bacigaluppi, Susanna; Robba, Chiara; Nardone, Raffaele; Trinka, Eugen; Brigo, Francesco

    2016-02-01

    People increasingly use Google looking for health-related information. We previously demonstrated that in English-speaking countries most people use this search engine to obtain information on status epilepticus (SE) definition, types/subtypes, and treatment. Now, we aimed at providing a quantitative analysis of SE-related web queries. This analysis represents an advancement, with respect to what was already previously discussed, in that the Google Trends (GT) algorithm has been further refined and correlational analyses have been carried out to validate the GT-based query volumes. Google Trends-based SE-related query volumes were well correlated with information concerning causes and pharmacological and nonpharmacological treatments. Google Trends can provide both researchers and clinicians with data on realities and contexts that are generally overlooked and underexplored by classic epidemiology. In this way, GT can foster new epidemiological studies in the field and can complement traditional epidemiological tools.

  20. Trends in evolution of 5S rRNA of deuterostomes: bases and homogeneous clusters

    Directory of Open Access Journals (Sweden)

    Sandra Maria Rodrigues Subacius

    2002-01-01

    Full Text Available Evolution of metazoan 5S rRNA sequences was analyzed through base composition and types, location and frequency of clustered bases. Characters from sequences of protostomes did not show regular trends as compared with paleontology dating or organism complexity. Trends of increasing G and C, stronger in G clusters, and decreasing A and U, were detected in deuterostomes, in parallel with evolution of complexity. The multifunctional domain 71-104 was highlighted among conserved stretches. Clusters of C were typical of helices. Those of G were longer, extending from helices into loops or related to bulges, which is suggestive of functional significance. Deuterostomian trends were installed early in the lineage and reached full development in aquatic organisms, not increasing further after reptiles. It can be suggested that ribosomal RNA structures participated in deuterostomian high regulatory complexity, either specifically or as part of the widespread processes of chromosomal regionalization.

  1. Investigating international time trends in the incidence and prevalence of atopic eczema 1990-2010: a systematic review of epidemiological studies.

    Directory of Open Access Journals (Sweden)

    Ivette A G Deckers

    Full Text Available The prevalence of atopic eczema has been found to have increased greatly in some parts of the world. Building on a systematic review of global disease trends in asthma, our objective was to study trends in incidence and prevalence of atopic eczema. Disease trends are important for health service planning and for generating hypotheses regarding the aetiology of chronic disorders. We conducted a systematic search for high quality reports of cohort, repeated cross-sectional and routine healthcare database-based studies in seven electronic databases. Studies were required to report on at least two measures of the incidence and/or prevalence of atopic eczema between 1990 and 2010 and needed to use comparable methods at all assessment points. We retrieved 2,464 citations, from which we included 69 reports. Assessing global trends was complicated by the use of a range of outcome measures across studies and possible changes in diagnostic criteria over time. Notwithstanding these difficulties, there was evidence suggesting that the prevalence of atopic eczema was increasing in Africa, eastern Asia, western Europe and parts of northern Europe (i.e. the UK. No clear trends were identified in other regions. There was inadequate study coverage worldwide, particularly for repeated measures of atopic eczema incidence. Further epidemiological work is needed to investigate trends in what is now one of the most common long-term disorders globally. A range of relevant measures of incidence and prevalence, careful use of definitions and description of diagnostic criteria, improved study design, more comprehensive reporting and appropriate interpretation of these data are all essential to ensure that this important field of epidemiological enquiry progresses in a scientifically robust manner.

  2. 'Failure limited' data and TTT-based trend tests in multiple repairable systems

    Energy Technology Data Exchange (ETDEWEB)

    Caroni, C., E-mail: ccar@math.ntua.g [Department of Mathematics, School of Applied Mathematical and Physical Sciences, National Technical University of Athens (NTUA), 9 Iroon Polytechniou, Zografou 157 80, Athens (Greece)

    2010-06-15

    Tests for trend in multiple repairable systems based on the total time on test (introduced by Kvaloy and Lindqvist) are valid for data that end at a failure time only if data collection was planned to continue until a predetermined number of failures had occurred. They are not valid for a commoner form of data that end with the last of a random number of failures within a predetermined observation period. The necessary modification to the analysis is given here and appropriate terminology is suggested.

  3. Trend analysis of performance parameters of pre-packed columns for protein chromatography over a time span of ten years.

    Science.gov (United States)

    Scharl, Theresa; Jungreuthmayer, Christian; Dürauer, Astrid; Schweiger, Susanne; Schröder, Tim; Jungbauer, Alois

    2016-09-23

    Pre-packed small scale chromatography columns are increasingly used for process development, for determination of design space in bioprocess development, and for post-licence process verifications. The packing quality of 30,000 pre-packed columns delivered to customers over a period 10 years has been analyzed by advanced statistical tools. First, the data were extracted and checked for inconsistencies, and then were tabulated and made ready for statistical processing using the programming language Perl (https://www.perl.org/) and the statistical computing environment R (https://www.r-project.org/). Reduced HETP and asymmetry were plotted over time to obtain a trend of packing quality over 10 years. The obtained data were used as a visualized coefficient of variation analysis (VCVA), a process that has often been applied in other industries such as semiconductor manufacturing. A typical fluctuation of reduced HETP was seen. A Tsunami effect in manufacturing, the effect of propagation of manufacturing deviations leading to out-of-specification products, was not observed with these pre-packed columns. Principal component analysis (PCA) showed that all packing materials cluster. Our data analysis showed that the current commercially available chromatography media used for biopharmaceutical manufacturing can be reproducibly and uniformly packed in polymer-based chromatography columns, which are designed for ready-to-use purposes. Although the number of packed columns has quadrupled over one decade the packing quality has remained stable.

  4. Trends of phytoplankton characteristics and their communities in pre- and post-liming time in Lake Orta (1984-1998

    Directory of Open Access Journals (Sweden)

    Pierisa PANZANI

    2001-02-01

    Full Text Available This paper is an assessment of the changing properties of Lake Orta phytoplankton in the period 1984-1998, which includes the large-scale liming carried out in the lake in 1989 and 1990. The phytoplankton is analysed first in its general properties (abundance, biovolume, chlorophyll-a concentration, average cell size, diversity by means of time courses of the mentioned variables based on monthly data through the entire period, and by correlations between the same variables. Moreover, through clustering techniques, the evolution of the species composition has been studied, showing the gradual decrease of chlorophytes after the liming and the noticeable increase of the diatom population, both as biovolume and diversity. Although the assemblage of the dominant species still mirrors the presence of some residual toxic compounds into the lake water, in the most recent period the evolution of the algal populations showed a clear trend towards a species assemblage more similar to those observed in the other deep italian subalpine lakes. After the improving of the chemical environment, the main abiotic factor that in the next years could play a major role in modifying the species assemblage is probably the phosphorus supply, whose in-lake concentration is low, despite the high annual load from the basin. A better understanding of the mechanisms underlying the phosphorus dynamics represent the basis to make reliable hypotheses about the future evolution of the phytoplankton assemblage.

  5. Trend analysis of performance parameters of pre-packed columns for protein chromatography over a time span of ten years.

    Science.gov (United States)

    Scharl, Theresa; Jungreuthmayer, Christian; Dürauer, Astrid; Schweiger, Susanne; Schröder, Tim; Jungbauer, Alois

    2016-09-23

    Pre-packed small scale chromatography columns are increasingly used for process development, for determination of design space in bioprocess development, and for post-licence process verifications. The packing quality of 30,000 pre-packed columns delivered to customers over a period 10 years has been analyzed by advanced statistical tools. First, the data were extracted and checked for inconsistencies, and then were tabulated and made ready for statistical processing using the programming language Perl (https://www.perl.org/) and the statistical computing environment R (https://www.r-project.org/). Reduced HETP and asymmetry were plotted over time to obtain a trend of packing quality over 10 years. The obtained data were used as a visualized coefficient of variation analysis (VCVA), a process that has often been applied in other industries such as semiconductor manufacturing. A typical fluctuation of reduced HETP was seen. A Tsunami effect in manufacturing, the effect of propagation of manufacturing deviations leading to out-of-specification products, was not observed with these pre-packed columns. Principal component analysis (PCA) showed that all packing materials cluster. Our data analysis showed that the current commercially available chromatography media used for biopharmaceutical manufacturing can be reproducibly and uniformly packed in polymer-based chromatography columns, which are designed for ready-to-use purposes. Although the number of packed columns has quadrupled over one decade the packing quality has remained stable. PMID:27575920

  6. The Living Planet Index: using species population time series to track trends in biodiversity.

    Science.gov (United States)

    Loh, Jonathan; Green, Rhys E; Ricketts, Taylor; Lamoreux, John; Jenkins, Martin; Kapos, Valerie; Randers, Jorgen

    2005-02-28

    The Living Planet Index was developed to measure the changing state of the world's biodiversity over time. It uses time-series data to calculate average rates of change in a large number of populations of terrestrial, freshwater and marine vertebrate species. The dataset contains about 3000 population time series for over 1100 species. Two methods of calculating the index are outlined: the chain method and a method based on linear modelling of log-transformed data. The dataset is analysed to compare the relative representation of biogeographic realms, ecoregional biomes, threat status and taxonomic groups among species contributing to the index. The two methods show very similar results: terrestrial species declined on average by 25% from 1970 to 2000. Birds and mammals are over-represented in comparison with other vertebrate classes, and temperate species are over-represented compared with tropical species, but there is little difference in representation between threatened and non-threatened species. Some of the problems arising from over-representation are reduced by the way in which the index is calculated. It may be possible to reduce this further by post-stratification and weighting, but new information would first need to be collected for data-poor classes, realms and biomes.

  7. Forty years trends in timing of pubertal growth spurt in 157,000 Danish school children

    DEFF Research Database (Denmark)

    Aksglæde, Lise; Olsen, Lina Wøhlk; Sørensen, Thorkild I.A.;

    2008-01-01

    study was to determine if the age at onset of pubertal growth spurt (OGS) and at peak height velocity (PHV) during puberty show secular trends during four decades in a large cohort of school children. METHODS AND FINDINGS: Annual measurements of height were available in all children born from 1930...... to 1969 who attended primary school in the Copenhagen Municipality. 135,223 girls and 21,612 boys fulfilled the criteria for determining age at OGS and age at PHV. These physiological events were used as markers of pubertal development in our computerized method in order to evaluate any secular trends....... The decline was non-linear with a levelling off in the children born between 1940 and 1955. The duration of puberty, as defined by the difference between age at OGS and age at PHV, increased slightly in boys, whereas it decreased in girls. CONCLUSION: Our finding of declining age at OGS and at PHV indicates...

  8. Information-time based futures pricing

    Science.gov (United States)

    Yen, Simon; Wang, Jai Jen

    2009-09-01

    This study follows Clark [P.K. Clark, A subordinated stochastic process model with finite variance for speculative prices, Econometrica 41 (1973) 135-155] and Chang, Chang and Lim [C.W. Chang, S.K. Chang, K.G. Lim, Information-time option pricing: Theory and empirical evidence, Journal of Financial Economics 48 (1998) 211-242] to subordinate an information-time based directing process into calendar-time based parent processes. A closed-form futures pricing formula is derived after taking into account the information-time setting and the stochasticity of the spot price, interest rate, and convenience yield. According to the empirical results on the TAIEX and TFETX data from 1998/7/21 to 2003/12/31, the information-time based model performs better than its calendar-time based counterpart and the cost of carry model, especially when the information arrival intensity estimates become larger.

  9. Educational Inequalities in Obesity among Mexican Women: Time-Trends from 1988 to 2012.

    OpenAIRE

    Carolina Perez Ferrer; Anne McMunn; Juan A Rivera Dommarco; Brunner, Eric J

    2014-01-01

    BACKGROUND: Obesity is one of the leading causes of global morbidity and mortality. Trends in educational inequalities in obesity prevalence among Mexican women have not been analysed systematically to date. METHODS: Data came from four nationally representative surveys (1988, 1999, 2006, and 2012) of a total of 51 220 non-pregnant women aged 20 to 49. Weight and height were measured during home visits. Education level (higher education, high school, secondary, primary or less) was self-repor...

  10. Characterization of Land Transitions Patterns from Multivariate Time Series Using Seasonal Trend Analysis and Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Benoit Parmentier

    2014-12-01

    Full Text Available Characterizing biophysical changes in land change areas over large regions with short and noisy multivariate time series and multiple temporal parameters remains a challenging task. Most studies focus on detection rather than the characterization, i.e., the manner by which surface state variables are altered by the process of changes. In this study, a procedure is presented to extract and characterize simultaneous temporal changes in MODIS multivariate times series from three surface state variables the Normalized Difference Vegetation Index (NDVI, land surface temperature (LST and albedo (ALB. The analysis involves conducting a seasonal trend analysis (STA to extract three seasonal shape parameters (Amplitude 0, Amplitude 1 and Amplitude 2 and using principal component analysis (PCA to contrast trends in change and no-change areas. We illustrate the method by characterizing trends in burned and unburned pixels in Alaska over the 2001–2009 time period. Findings show consistent and meaningful extraction of temporal patterns related to fire disturbances. The first principal component (PC1 is characterized by a decrease in mean NDVI (Amplitude 0 with a concurrent increase in albedo (the mean and the annual amplitude and an increase in LST annual variability (Amplitude 1. These results provide systematic empirical evidence of surface changes associated with one type of land change, fire disturbances, and suggest that STA with PCA may be used to characterize many other types of land transitions over large landscape areas using multivariate Earth observation time series.

  11. Unified Methodology for Detecting Trend Changes and Outliers in Time Series: application to Ground Deformation in the Virunga Volcanic Province.

    Science.gov (United States)

    Arjona, A.; d'Oreye, N.

    2014-12-01

    Detecting trend changes and outliers are common needs in applied time series analysis. Here we propose a tool combining various robust methods to perform simultaneously these two tasks. Such a unified tool is well adapted to the analysis of extensive databases. We use it to analyze ground deformations associated to volcanic activity in the Virunga Volcanic Province. Trend changes are estimated using weighted moving average filter, locally weighted scatterplot smoothers and smoothing splines. Significance of detected trend changes is estimated using parametric and non-parametric statistical tests such as Mann-Kendall, Spearmans Rho and Pearson correlation methods. Outliers are detected using both standardized residuals from best-fit model and Chebyshev's inequality. On one side observations that have a studentized residual outside the ± 2 range are considered statistically significant at the 95% a level and potential outliers. On the other hand Chebyshev's inequality gives a bound of what percentage of the data falls outside of k standard deviations from the mean calculating upper and lower outlier detection limits. When multiple components of displacements are available (such as vertical, North-South and East-West GPS time series), the outliers detection is performed on each component separately, then jointly. The effectiveness of the tool is demonstrated by analyzing 5 years of data recorded by the permanent GNSS volcano monitoring network in Goma as well as the extensive amount of MSBAS Multidimensional InSAR time series (Samsonov and dOreye, 2012) recorded in the Virunga during 2003-2013 time period.

  12. THE EFFECT OF DECOMPOSITION METHOD AS DATA PREPROCESSING ON NEURAL NETWORKS MODEL FOR FORECASTING TREND AND SEASONAL TIME SERIES

    Directory of Open Access Journals (Sweden)

    Subanar Subanar

    2006-01-01

    Full Text Available Recently, one of the central topics for the neural networks (NN community is the issue of data preprocessing on the use of NN. In this paper, we will investigate this topic particularly on the effect of Decomposition method as data processing and the use of NN for modeling effectively time series with both trend and seasonal patterns. Limited empirical studies on seasonal time series forecasting with neural networks show that some find neural networks are able to model seasonality directly and prior deseasonalization is not necessary, and others conclude just the opposite. In this research, we study particularly on the effectiveness of data preprocessing, including detrending and deseasonalization by applying Decomposition method on NN modeling and forecasting performance. We use two kinds of data, simulation and real data. Simulation data are examined on multiplicative of trend and seasonality patterns. The results are compared to those obtained from the classical time series model. Our result shows that a combination of detrending and deseasonalization by applying Decomposition method is the effective data preprocessing on the use of NN for forecasting trend and seasonal time series.

  13. The Diverge of Liquidity and Inflation in the After-Crisis Time--Based on the Trend of Inflation Over Time%后危机时代流动性过剩与通货膨胀的偏离--基于长期通货膨胀趋势的解释视角

    Institute of Scientific and Technical Information of China (English)

    栗亮

    2014-01-01

    The paper argues the reason why the liquidity excess did not lead to the acceleration of inflation in the present time is because that inflation rate will drop over time. However, the asset price plays some roles in short term. We try to explain that why the liquidity excess did not raise the inflation, and we think the most mainly reasons are inflation targeting, the independence of central bank and the globalization.%本文认为此轮流动性过剩没有导致通货膨胀率明显上升的主要原因在长期来看应该是通货膨胀率不断降低的一般规律,在短期来看,资产价格起到了一定作用。本文试图从目标通货膨胀制、央行独立性和全球化的角度解释尽管目前全球出现普遍性的流动性过剩,但是通货膨胀却保持在相对平稳水平的原因。

  14. Complementary feeding patterns in the first year of life in the city of Rio de Janeiro, Brazil: time trends from 1998 to 2008

    Directory of Open Access Journals (Sweden)

    Daniel Alves de Oliveira

    2014-08-01

    Full Text Available This study aimed to analyze time trends in complementary feeding practices among children under one year of age in the city of Rio de Janeiro, Brazil, from 1998 to 2008. Based on comparable questions on food consumption in five surveys conducted in representative randomized samples of children in 1998 (n = 3,762, 2000 (n = 3,670, 2003 (n = 4,305, 2006 (n = 3,686, and 2008 (n = 2,621, 16 complementary feeding indicators were constructed. The percentage frequency of all indicators was estimated for each year of the study. Linear trend analyses were also conducted by means of multivariate regression models. All indicators of early complementary feeding decreased from 1998 to 2008. In the 6-11.9 month age group, there was a significant downward trend in the proportion of children receiving food with adequate consistency for their age, consumption of iron-rich foods, and overall adequacy of the diet. A significant upward trend in fruit consumption was observed. There was a decrease in the early complementary feeding, and generally a worsening of complementary feeding practices in children aged 6-11.9 months in Rio de Janeiro during the period studied.

  15. Inevitable end-of-21st-century trends toward earlier surface runoff timing in California's Sierra Nevada Mountains

    Science.gov (United States)

    Schwartz, M. A.; Hall, A. D.; Sun, F.; Walton, D.; Berg, N.

    2015-12-01

    Hybrid dynamical-statistical downscaling is used to produce surface runoff timing projections for California's Sierra Nevada, a high-elevation mountain range with significant seasonal snow cover. First, future climate change projections (RCP8.5 forcing scenario, 2081-2100 period) from five CMIP5 global climate models (GCMs) are dynamically downscaled. These projections reveal that future warming leads to a shift toward earlier snowmelt and surface runoff timing throughout the Sierra Nevada region. Relationships between warming and surface runoff timing from the dynamical simulations are used to build a simple statistical model that mimics the dynamical model's projected surface runoff timing changes given GCM input or other statistically-downscaled input. This statistical model can be used to produce surface runoff timing projections for other GCMs, periods, and forcing scenarios to quantify ensemble-mean changes, uncertainty due to intermodel variability and consequences stemming from choice of forcing scenario. For all CMIP5 GCMs and forcing scenarios, significant trends toward earlier surface runoff timing occur at elevations below 2500m. Thus, we conclude that trends toward earlier surface runoff timing by the end-of-the-21st century are inevitable. The changes to surface runoff timing diagnosed in this study have implications for many dimensions of climate change, including impacts on surface hydrology, water resources, and ecosystems.

  16. Estimated and forecasted trends in domain specific time-use and energy expenditure among adults in Russia

    OpenAIRE

    Dearth-Wesley, Tracy; Popkin, Barry M; Ng, Shu Wen

    2014-01-01

    Background Examination of historical trends and projections in estimated energy expenditure in Russia is important given the country’s economic downturns and growth. Methods Nationally representative data from the Russia Longitudinal Monitoring Survey (RLMS) from 1995–2011 was used to determine the metabolic equivalents of task (MET)-hours per week from occupational, domestic, travel, and active leisure physical activity (PA) domains, as well as sedentary leisure time (hours per week) among a...

  17. Time trends and sex differences in associations between socioeconomic status indicators and overweight-obesity in Mexico (2006–2012)

    OpenAIRE

    Quezada, Amado D.; Lozada-Tequeanes, Ana L.

    2015-01-01

    Background Although the associations between specific socioeconomic status (SES) indicators and overweight or obesity (OWOB) have been studied in different countries, fewer evidence exists for these associations when multiple SES indicators are considered simultaneously. Furthermore, there are few studies investigating time trends in OWOB and their relation with SES in upper-middle income countries, especially for men. The present study contributes to a better understanding of the nature and ...

  18. Systematic review of time trends in the prevalence of Helicobacter pylori infection in China and the USA.

    Science.gov (United States)

    Nagy, Peter; Johansson, Saga; Molloy-Bland, Michael

    2016-01-01

    It has been suggested that the prevalence of Helicobacter pylori infection has stabilized in the USA and is decreasing in China. We conducted a systematic literature analysis to test this hypothesis. PubMed and Embase searches were conducted up to 19 January 2015. Trends in the prevalence of H. pylori infection over time were assessed by regression analysis using Microsoft Excel. Overall, 25 Chinese studies (contributing 28 datasets) and 11 US studies (contributing 11 datasets) were included. There was a significant decrease over time in the H. pylori infection prevalence for the Chinese studies overall (p = 0.00018) and when studies were limited to those that used serum immunoglobulin G (IgG) assays to detect H. pylori infection (p = 0.014; 20 datasets). The weighted mean prevalence of H. pylori infection was 66 % for rural Chinese populations and 47 % for urban Chinese populations. There was a significant trend towards a decreasing prevalence of H. pylori infection for studies that included only urban populations (p = 0.04; 9 datasets). This trend was no longer statistically significant when these studies were further restricted to those that used serum IgG assays to detect H. pylori infection, although this may have been because of low statistical power due to the small number of datasets available for this analysis (p = 0.28; 6 datasets). There were no significant trends in terms of changes in the prevalence of H. pylori infection over time for studies conducted in the USA. In conclusion, the prevalence of H. pylori infection is most likely decreasing in China, due to a combination of increasing urbanization, which we found to be associated with lower H. pylori infection rates, and possibly also decreasing rates of H. pylori infection within urban populations. This will probably result in a gradual decrease in peptic ulcer and gastric cancer rates in China over time.

  19. PREVALENCE OF CHILD MARRIAGE AMONG BANGLADESHI WOMEN AND TREND OF CHANGE OVER TIME.

    Science.gov (United States)

    Hossain, Md Golam; Mahumud, Rashidul Alam; Saw, Aik

    2016-08-01

    Many Bangladeshi women marry early, and many marry before the legal age of 18 years. This practice has been associated with a higher risk of health and medical morbidities, and also early pregnancy with higher pre- and postnatal complications. The aim of this study was to determine the prevalence, and factors associated with, child marriage among Bangladeshi women using multiple binary logistic regression analysis of data from the BDHS-2011. Further analysis on the trend of age at first marriage was performed with additional data sets from previous surveys. The mean and median of ages at first marriage of Bangladeshi women in 2011 were 15.69±2.97 and 15.00 years, respectively. A remarkably high percentage (78.2%) married before the age of 18; of these, 5.5% married at a very early age (before 13 years of age). Binary logistic regression analysis demonstrated that uneducated women were more likely to be married early (pmarriage was especially pronounced among women with uneducated husbands, Muslims, those with poor economic backgrounds and those living in rural areas. Further analysis including data from previous BDHS surveys showed that child marriage among Bangladeshi women had a decreasing trend from 1993-94 to 2011. These results show that child marriage was very common in Bangladesh, and closely associated with low level of education and low economic status. The decreasing trend in child marriage indicates an improvement over the past two decades but more effort is needed to further reduce and eventually eliminate the practice. PMID:26286142

  20. The development trend of animation character style design in new times

    Institute of Scientific and Technical Information of China (English)

    罗淞译

    2015-01-01

    Animation industry in the new period had achieved optimized development, which is stimulating to transform animation character modeling design thought, forming more diversified animation industry pattern. Animation industry in China must adhere to the road of reform and innovation so that it could realize upgrading of industrial structure and sustainable development., The early characters style is necessarily to be changed from design stage which as the beginning of the reform in order to promote the transform of variety of new characters style. This paper aims to analyze animation character style design concept, summarize future character style design development trend, and put forward feasible character style design plans.

  1. Educational inequalities in obesity among Mexican women: time-trends from 1988 to 2012.

    Directory of Open Access Journals (Sweden)

    Carolina Perez Ferrer

    Full Text Available BACKGROUND: Obesity is one of the leading causes of global morbidity and mortality. Trends in educational inequalities in obesity prevalence among Mexican women have not been analysed systematically to date. METHODS: Data came from four nationally representative surveys (1988, 1999, 2006, and 2012 of a total of 51 220 non-pregnant women aged 20 to 49. Weight and height were measured during home visits. Education level (higher education, high school, secondary, primary or less was self-reported. We analysed trends in relative and absolute educational inequalities in obesity prevalence separately for urban and rural areas. RESULTS: Nationally, age-standardised obesity prevalence increased from 9.3% to 33.7% over 25 years to 2012. Obesity prevalence was inversely associated with education level in urban areas at all survey waves. In rural areas, obesity prevalence increased markedly but there was no gradient with education level at any survey. The relative index of inequality in urban areas declined over the period (2.87 (95%CI: 1.94, 4.25 in 1988, 1.55 (95%CI: 1.33, 1.80 in 2012, trend p<0.001. Obesity increased 5.92 fold (95%CI: 4.03, 8.70 among urban women with higher education in the period 1988-2012 compared to 3.23 fold (95%CI: 2.88, 3.63 for urban women with primary or no education. The slope index of inequality increased in urban areas from 1988 to 2012. Over 0.5 M cases would be avoided if the obesity prevalence of women with primary or less education was the same as for women with higher education. CONCLUSIONS: The expected inverse association between education and obesity was observed in urban areas of Mexico. The declining trend in relative educational inequalities in obesity was due to a greater increase in obesity prevalence among higher educated women. In rural areas there was no social gradient in the association between education level and obesity across the four surveys.

  2. Varying spatial patterns of trend and seasonality in Eurasian runoff time series

    Directory of Open Access Journals (Sweden)

    R. Rödel

    2006-01-01

    Full Text Available Atmospheric circulation indices can be used to explain the variability of runoff on a continental scale. Beside well-known regional anomalies of precipitation and runoff that correlate with phases of the North Atlantic Oscillation (NAO there are also drifting fields of annual discharge anomalies. Following the trend of the NAO, these fields move along a longitudinal axis from western Europe to the Lena catchment in Siberia and back again. The same pattern is observable in the changing flow regimes. This paper describes the origin and causes of these anomaly fields and explains them as the results of important climate variations in the northern hemisphere.

  3. Global distribution and trends of tropospheric ozone: An observation-based review

    Directory of Open Access Journals (Sweden)

    O. R. Cooper

    2014-07-01

    Full Text Available Abstract Tropospheric ozone plays a major role in Earth’s atmospheric chemistry processes and also acts as an air pollutant and greenhouse gas. Due to its short lifetime, and dependence on sunlight and precursor emissions from natural and anthropogenic sources, tropospheric ozone’s abundance is highly variable in space and time on seasonal, interannual and decadal time-scales. Recent, and sometimes rapid, changes in observed ozone mixing ratios and ozone precursor emissions inspired us to produce this up-to-date overview of tropospheric ozone’s global distribution and trends. Much of the text is a synthesis of in situ and remotely sensed ozone observations reported in the peer-reviewed literature, but we also include some new and extended analyses using well-known and referenced datasets to draw connections between ozone trends and distributions in different regions of the world. In addition, we provide a brief evaluation of the accuracy of rural or remote surface ozone trends calculated by three state-of-the-science chemistry-climate models, the tools used by scientists to fill the gaps in our knowledge of global tropospheric ozone distribution and trends.

  4. Satellite-based analysis of recent trends in the ecohydrology of a semi-arid region

    Directory of Open Access Journals (Sweden)

    M. Gokmen

    2013-10-01

    Full Text Available We present a regional framework for an integrated and spatiotemporally distributed assessment of human-induced trends in the hydrology and the associated ecological health of a semi-arid basin where both human activities (i.e. agriculture and natural ecosystems are highly groundwater dependent. To achieve this, we analysed the recent trends (from year 2000 to 2010 in precipitation, evapotranspiration (actual and potential and vegetation greenness (i.e. NDVI using a combination of satellite and ground-based observations. The trend assessment was applied for the semi-arid Konya Basin (Turkey, one of the largest endorheic basins in the world. The results revealed a consistent increasing trend of both yearly evapotranspiration (totally 63 MCM yr−1 from croplands and mean NDVI (about 0.004 NDVI yr−1 in irrigated croplands, especially concentrating in the plain part of the basin, while no significant trends were observed for the precipitation and potential evapotranspiration variables. On the contrary, a consistent decreasing trend of both yearly evapotranspiration (totally −2.1 MCM yr−1 and mean NDVI (−0.001 NDVI yr−1 was observed in the wetlands, which also cannot be explained by trends in precipitation and potential evapotranspiration. The emerging picture suggest that the greening trend of the vegetation and increasing of evapotranspiration in the plain are related to land cover changes (i.e. conversion into irrigated croplands and to the intensification of the supplementary irrigation for agriculture, which in turn caused drying out of some wetlands and the natural vegetation which mostly depend on the groundwater, the main source of irrigation water as well. Our study presented an example of the utility of spatially and temporally continuous RS data in assessing the regional trends in hydrological and ecological variables and their interactions in a spatially distributed manner in a semi-arid region, which can also be adapted to

  5. Health Habits of Employees in a Large Medical Center: Time Trends and Impact of a Worksite Wellness Facility

    OpenAIRE

    Abd Moain Abu Dabrh; Archana Gorty; Sarah M Jenkins; Mohammad Hassan Murad; Hensrud, Donald D.

    2016-01-01

    Worksite health interventions are not novel but their effect remains subject of debate. We examined employer-based wellness program to determine health habits trends, and compare prevalence estimates to national data. We conducted serial surveys (1996 and 2007–10) to employees of a large medical center that included questions measuring outcomes, including obesity, regular exercise, cardiovascular activity, and smoking status. Logistic regression models were estimated to compare data by member...

  6. An Examination of Temporal Trends in Electricity Reliability Based on Reports from U.S. Electric Utilities

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H.; LaCommare, Kristina Hamachi; Larsen, Peter; Todd, Annika; Fisher, Emily

    2012-01-06

    Since the 1960s, the U.S. electric power system has experienced a major blackout about once every 10 years. Each has been a vivid reminder of the importance society places on the continuous availability of electricity and has led to calls for changes to enhance reliability. At the root of these calls are judgments about what reliability is worth and how much should be paid to ensure it. In principle, comprehensive information on the actual reliability of the electric power system and on how proposed changes would affect reliability ought to help inform these judgments. Yet, comprehensive, national-scale information on the reliability of the U.S. electric power system is lacking. This report helps to address this information gap by assessing trends in U.S. electricity reliability based on information reported by electric utilities on power interruptions experienced by their customers. Our research augments prior investigations, which focused only on power interruptions originating in the bulk power system, by considering interruptions originating both from the bulk power system and from within local distribution systems. Our research also accounts for differences among utility reliability reporting practices by employing statistical techniques that remove the influence of these differences on the trends that we identify. The research analyzes up to 10 years of electricity reliability information collected from 155 U.S. electric utilities, which together account for roughly 50% of total U.S. electricity sales. The questions analyzed include: 1. Are there trends in reported electricity reliability over time? 2. How are trends in reported electricity reliability affected by the installation or upgrade of an automated outage management system? 3. How are trends in reported electricity reliability affected by the use of IEEE Standard 1366-2003?

  7. Trends over time in tree and seedling phylogenetic diversity indicate regional differences in forest biodiversity change.

    Science.gov (United States)

    Potter, Kevin M; Woodall, Christopher W

    2012-03-01

    Changing climate conditions may impact the short-term ability of forest tree species to regenerate in many locations. In the longer term, tree species may be unable to persist in some locations while they become established in new places. Over both time frames, forest tree biodiversity may change in unexpected ways. Using repeated inventory measurements five years apart from more than 7000 forested plots in the eastern United States, we tested three hypotheses: phylogenetic diversity is substantially different from species richness as a measure of biodiversity; forest communities have undergone recent changes in phylogenetic diversity that differ by size class, region, and seed dispersal strategy; and these patterns are consistent with expected early effects of climate change. Specifically, the magnitude of diversity change across broad regions should be greater among seedlings than in trees, should be associated with latitude and elevation, and should be greater among species with high dispersal capacity. Our analyses demonstrated that phylogenetic diversity and species richness are decoupled at small and medium scales and are imperfectly associated at large scales. This suggests that it is appropriate to apply indicators of biodiversity change based on phylogenetic diversity, which account for evolutionary relationships among species and may better represent community functional diversity. Our results also detected broadscale patterns of forest biodiversity change that are consistent with expected early effects of climate change. First, the statistically significant increase over time in seedling diversity in the South suggests that conditions there have become more favorable for the reproduction and dispersal of a wider variety of species, whereas the significant decrease in northern seedling diversity indicates that northern conditions have become less favorable. Second, we found weak correlations between seedling diversity change and latitude in both zones

  8. Evaluation of Monitoring Schemes for Wastewater-Based Epidemiology to Identify Drug Use Trends Using Cocaine, Methamphetamine, MDMA and Methadone.

    Science.gov (United States)

    Humphries, Melissa A; Bruno, Raimondo; Lai, Foon Yin; Thai, Phong K; Holland, Barbara R; O'Brien, Jake W; Ort, Christoph; Mueller, Jochen F

    2016-05-01

    Wastewater-based epidemiology is increasingly being used as a tool to monitor drug use trends. To minimize costs, studies have typically monitored a small number of days. However, cycles of drug use may display weekly and seasonal trends that affect the accuracy of monthly or annual drug use estimates based on a limited number of samples. This study aimed to rationalize sampling methods for minimizing the number of samples required while maximizing information about temporal trends. A range of sampling strategies were examined: (i) targeted days (e.g., weekends), (ii) completely random or stratified random sampling, and (iii) a number of sampling strategies informed by known weekly cycles in drug use data. Using a time-series approach, analysis was performed for four drugs (MDMA, methamphetamine, cocaine, methadone) collected through a continuous sampling program over 14 months. Results showed, for drugs with weekly cycles (MDMA, methamphetamine and cocaine in this sample), sampling strategies which made use of those weekly cycles required fewer samples to obtain similar information as sampling 5 days per week and had better accuracy than stratified random sampling techniques. PMID:27007609

  9. Graduating dental students' views of competency statements: importance, confidence, and time trends from 2008 to 2012.

    Science.gov (United States)

    Whitney, Eli M; Walton, Joanne N; Aleksejuniene, Jolanta; Schönwetter, Dieter J

    2015-03-01

    Competency documents are used in dental education as both an educational framework and an accreditation instrument. The aim of this study was to analyze the perceptions of graduating dental students at the University of British Columbia (UBC) regarding the importance of each competency statement, as well as to assess their confidence in their abilities associated with each statement. The instrument was based on the survey developed by Schönwetter et al. at the University of Manitoba using the Association of Canadian Faculties of Dentistry competency document. The current study surveyed UBC graduating students in the years 2008 through 2012. The response rates ranged from 66.7% to 95.9%, averaging 77.5% across all five years. The results showed that, overall, the students rated all the competencies as important, but they rated their confidence lower than the perceived importance. Correlation coefficients averaged a moderate correlation of 0.376 for all competency statements except the five with the greatest discrepancy between perceived importance and confidence. The competencies the students perceived as most important tended to be associated with tasks frequently performed during predoctoral dental education. The instrument used in this study can help other academic dental institutions identify patterns of students' perceived competency importance and confidence to inform allocation of teaching time and resources and adopt new methodologies to address identified areas of need.

  10. Time Trends in Fast Food Consumption and Its Association with Obesity among Children in China.

    Directory of Open Access Journals (Sweden)

    Hong Xue

    Full Text Available Study the trends in Western fast food consumption (FFC among Chinese school-age children and the association between FFC and obesity using nationwide survey data.Cross-sectional and longitudinal analyses were conducted to study the trends in FFC and the associations between FFC and weight status (overweight, obesity and body mass index (BMI z-score.Longitudinal data from families were collected in the 2004 and 2009 China Health and Nutrition Survey (covering nine provinces throughout China.The analysis included 2656 Chinese children aged 6 to 18 years (1542 and 1114 children in the 2004 and 2009 survey, respectively.FFC (reported having consumed Western fast food in the past three months has increased between 2004 and 2009, from 18.5% to 23.9% in those aged 6-18, and increased more rapidly among those aged 13-17, from 17.9% to 26.3%. The increase was significant in almost all groups by age, sex, family income, and residence. Our cross-sectional and longitudinal analyses did not detect a significant association between FFC and obesity/overweight or BMI z-score (e.g., for BMI z-score, boys: β = 0.02, 95% CI: -0.71, 0.75; girls: β = -0.14, 95% CI: -1.03, 0.75.FFC has increased in Chinese school-age children, especially in older children, boys, and those from low- and medium-income families, rural areas, and East China, but decreased among those from high-income families during 2004-2009. The data did not show a significant association between FFC and obesity.

  11. Analysis in Trend of Welfare Gains' Distribution during the TPP' s Expansion:Based on Spatial Time Series Model%TPP扩张过程中的福利收益分配趋势分析——基于时空数列模型的探讨

    Institute of Scientific and Technical Information of China (English)

    朱润东

    2012-01-01

    In this paper, welfare map and modified spatial time series model are adopted to investigate the impact of the TPP' s expansion on national(regional) welfare gains,in order to reveal the space - time evolution of the national(regional) welfare gains. The results show that, the welfare map can directly demonstrate the space- time evolution of the national (regional) welfare gains' distribution in the TPP' s expansion process ; the group distribution divided by the economic environment and the one divided by adding up the political and socio - cultural environment are quite different with each other; the community difference represents the differences among the national(regional) economic political and socio cultural environment,and also reflects the differences in trends of welfare gains' fluctuation in each country(region). It shows that there are three different trends of the effects and a special case which are showed in the four groups.%本文以福利地图与修正的时空数列模型来探讨泛太平洋战略经济伙伴关系协定扩张过程对各国(地区)福利收益产生的影响,揭示福利收益在各国(地区)间分配的时空演变趋势。结果发现,福利地图的确能直观表现出随着泛太平洋战略经济伙伴关系协定的不断扩张,区域内外各国(地区)的福利收益分配在时空上是如何演变的;根据经济环境划分出的群落分布和加入了政治与社会文化环境后所得到的群落分布状况是不同的;群落差异代表了各国(地区)经济和政治社会文化环境的差异性,也反映出在环境差异下各国(地区)所获福利收益变动趋势的差异,四群落间呈现出三种不同的效应变动趋势和一个特例。

  12. Current trends in virtual high throughput screening using ligand-based and structure-based methods.

    Science.gov (United States)

    Sukumar, Nagamani; Das, Sourav

    2011-12-01

    High throughput in silico methods have offered the tantalizing potential to drastically accelerate the drug discovery process. Yet despite significant efforts expended by academia, national labs and industry over the years, many of these methods have not lived up to their initial promise of reducing the time and costs associated with the drug discovery enterprise, a process that can typically take over a decade and cost hundreds of millions of dollars from conception to final approval and marketing of a drug. Nevertheless structure-based modeling has become a mainstay of computational biology and medicinal chemistry, helping to leverage our knowledge of the biological target and the chemistry of protein-ligand interactions. While ligand-based methods utilize the chemistry of molecules that are known to bind to the biological target, structure-based drug design methods rely on knowledge of the three-dimensional structure of the target, as obtained through crystallographic, spectroscopic or bioinformatics techniques. Here we review recent developments in the methodology and applications of structure-based and ligand-based methods and target-based chemogenomics in Virtual High Throughput Screening (VHTS), highlighting some case studies of recent applications, as well as current research in further development of these methods. The limitations of these approaches will also be discussed, to give the reader an indication of what might be expected in years to come. PMID:21843144

  13. An Assessment on Influences of Crises on Zhangjiajie Tourism: Analysis Based on the Tourism Background Trend Line in High Time Resolution%危机事件对张家界旅游影响评价——基于本底线模型的高分辨率分析

    Institute of Scientific and Technical Information of China (English)

    张铁生; 孙根年; 马丽君

    2012-01-01

    Using the statistics data of Zhangjiajie tourism from 200l to 2011, the four background trend lines of inbound and domestic tourist arrivals and tourism income were found on the basis of the theory of natural trend curve. This paper analyzes the influences of crises on Zhangjiajie inbound and domestic tourism by using monthly index on the tourism background trend line in high time resolution. The results show that the tourism industry is a sensitive and powerful self recovery ability industry. The tourism industry can always quick rebound on the heels of the crisis. In the end the tourism background trend line always pulled concave vale back, as the lifeline of tourism development. The results implied that Zhangjiajie has an obvious anti periodicity effect and rebound feature on the heels of crisis, science it has become well-known at home and abroad as a tourist destination. With the rapid economical development, domestic tourism has strong ascending inertia and rebound ability on the heels of crisis, but inbound tourism is more vulnerable. As international crisis, "SARS" and "international financial crisis" have great influence on Zhangjiajie tourism, and they have a long cycle. However, "Natural disaster" has slight effect on the Zhangjiajie tourism. The study provided a scientific basis for establishing crisis advance warning system and management system.%根据张家界2001--2011年旅游统计数据,建立入境旅游客流量及旅游外汇收入、国内旅游客流量及旅游收入四条本底趋势线,引入月指数的概念,基于本底线模型的高分辨率分析危机事件对张家界旅游的影响。研究表明,旅游业既是一个敏感性产业,又是一个自我恢复力强的产业,在危机之后往往能强力反弹,旅游本底趋势线作为旅游业发展的生命线,始终能够把危机形成的凹型谷吸引回来。研究认为,张家界作为国内外知名品牌景区,具有抗周期性和后危机反弹的

  14. Emerging medical informatics research trends detection based on MeSH terms.

    Science.gov (United States)

    Lyu, Peng-Hui; Yao, Qiang; Mao, Jin; Zhang, Shi-Jing

    2015-01-01

    The aim of this study is to analyze the research trends of medical informatics over the last 12 years. A new method based on MeSH terms was proposed to identify emerging topics and trends of medical informatics research. Informetric methods and visualization technologies were applied to investigate research trends of medical informatics. The metric of perspective factor (PF) embedding MeSH terms was appropriately employed to assess the perspective quality for journals. The emerging MeSH terms have changed dramatically over the last 12 years, identifying two stages of medical informatics: the "medical imaging stage" and the "medical informatics stage". The focus of medical informatics has shifted from acquisition and storage of healthcare data by integrating computational, informational, cognitive and organizational sciences to semantic analysis for problem solving and clinical decision-making. About 30 core journals were determined by Bradford's Law in the last 3 years in this area. These journals, with high PF values, have relative high perspective quality and lead the trend of medical informatics.

  15. A comparison of heat wave climatologies and trends in China based on multiple definitions

    Science.gov (United States)

    You, Qinglong; Jiang, Zhihong; Kong, Lei; Wu, Zhiwei; Bao, Yutao; Kang, Shichang; Pepin, Nick

    2016-08-01

    Heat waves (HWs) can have disastrous impacts on human activities and natural systems, and are one of the current foci of scientific research, particularly in the context of global warming. However, there is no standard definition of a HW, which makes assessment of temporal trends a challenge. In this study, based on daily mean, maximum and minimum temperature, and relative humidity datasets from China Meteorological Administration, the patterns, trends and variations of HW in China during 1961-2014 are investigated. Sixteen previously published HW indices (HIs) are calculated, which are divided into two types using relative and absolute threshold temperatures, respectively. During 1961-2014, both relative and absolute threshold HIs show the highest number of HW in Jianghua and South China, geographically consistent with the climate characteristics of China. The majority of HIs shows negative/positive trends of HW days before/after 1990 over the whole of China, but especially in Jianghua and South China, which reflects rapid warming since 1990. There are significant correlations among different HIs in the same type (both absolute and relative), but correlations are weak between relative and absolute threshold HIs. Because relative and absolute HIs show contrasting trends, the choice of HI is therefore critical for future analysis

  16. Are societal changes new? Questions or trends and future perceptions on knowledge-based economy

    OpenAIRE

    Margarida R. Paulos; António B. Moniz

    2009-01-01

    With the emergence of a global division of labour, the internationalisation of markets and cultures, the growing power of supranational organisations and the spread of new information technologies to every field of life, it starts to appear a different kind of society, different from the industrial society, and called by many as ‘the knowledge-based economy’, emphasizing the importance of information and knowledge in many areas of work and organisation of societies. Despite the common trends ...

  17. Share price trend based on analysis of investor’s online activity

    Directory of Open Access Journals (Sweden)

    Mihail Dumitru SACALĂ

    2011-07-01

    Full Text Available The desire of modeling the influence coming from behavioral economics, representing mostly qualitative variables, requires new approaches to quantify this influence. In this paper we present an analytical method for determining the direction of the share future return using an aggregate indicator calculated based exclusively on the trend of registered variables from investor’s online activity. This online activity refers to the number and content of messages posted by investors on shares analysis dedicated web blogs.

  18. Ethnic differences in the time trend of female breast cancer incidence: Singapore, 1968 – 2002

    Directory of Open Access Journals (Sweden)

    Tan Chuen-Seng

    2006-11-01

    Full Text Available Abstract Background From 1968 to 2002, Singapore experienced an almost three-fold increase in breast cancer incidence. This increase appeared to be different across the three main ethnic groups: Chinese, Malays and Indians. This paper used age-period-cohort (APC modelling, to determine the effects of age at diagnosis, calendar period, and birth cohort on breast cancer incidence for each ethnic group. Methods This study included all breast cancer cases (n = 15,269 in the three ethnic groups, reported to the Singapore Cancer Registry from 1968 to 2002 between the ages 25 to 79. Age-specific fertility rates from the Department of Statistics were used to explore the role of fertility. Results In the 1970s, Indian women had the highest age-standardized breast cancer but by the mid-1980s the highest rates were seen among the Chinese. Remarkable differences were seen in the age-specific incidence rates by ethnic groups. After age 49, the incidence rates for the Chinese and Malays leveled off whereas it continued to rise in the Indians. While our analyses provided some evidence that an age-drift model described the trend seen in the Indians, age-period-cohort model and age-cohort model had the best fit for the Chinese and Malays aged 25 to 79 respectively. Overall, Chinese and Malay women born in later cohorts were at increased risk of developing breast cancer relative to their counterparts in the earlier cohorts. The three ethnic groups experienced similar changes in their fertility in the 1970s, which likely explained much of the increase in their breast cancer incidence but not the ethnic differences. There was a stronger inverse association between total fertility rate and pre-menopausal breast cancer incidence in the Chinese and Malays than the Indians. Conclusion The observed dissimilarity among ethnic groups suggests ethnic differences in exposure or response to certain risk factors. It is likely that longer and subtler differences in

  19. The road to success. Long-term prognosis for persons living with HIV in Denmark - time trends and risk factors.

    Science.gov (United States)

    Lohse, Nicolai

    2016-02-01

    detection practice. Once diagnosed, getting the full benefit of modern HIV care requires access to a good healthcare system. We compared temporal trends in quality and quantity of ART introduction in Den-mark and Greenland. Despite similar levels of health worker education and economic resources, ART implementation and mortality decline in Greenland lacked several years behind Denmark. The study reminded us that although economy may be a prerequisite for implementing an effective HIV care system, it is certainly not all it takes. The nationwide nature of the Danish HIV Cohort Study also allowed us to study a number of time trends at the population level. Despite what was feared, we found that the prevalence of triple-drug class virological failure (TCF) seemed to have stabilized after 2000; that the incidence rates of drug resistance acquisition were decreasing during 1999-2005; and that the prevalence of potential transmitters of drug-resistant HIV decreased during 1997-2004. We also looked at some of the consequences of virological failure and drug resistance and found that even modest levels of viraemia were associated with a high risk of future failure and death, and that in persons who have experienced TCF, the number and pattern of resistance mutations were independent predictors of death. Hence, despite the overall positive trends in virological failure and drug-resistance development at the population level, our findings underline the crucial importance of always having an effective treatment option available for the individual patient with drug-resistant virus. As mortality was declining for persons with access to ART and good HIV care, it became important to know how long persons with HIV could expect to live compared to the general population. We projected long-term survival and found that a 25-year old person with HIV and without hepatitis C virus (HCV) co-infection had a 50 per cent chance of surviving another 39 years, only 12.2 years less than a person in a

  20. Smart handover based on fuzzy logic trend in IEEE802.11 mobile IPv6 networks

    CERN Document Server

    Lim, Joanne Mun-Yee

    2012-01-01

    A properly designed handoff algorithm is essential in reducing the connection quality deterioration when a mobile node moves across the cell boundaries. Therefore, to improve communication quality, we identified three goals in our paper. The first goal is to minimize unnecessary handovers and increase communication quality by reducing misrepresentations of RSSI readings due to multipath and shadow effect with the use of additional parameters. The second goal is to control the handover decisions depending on the users' mobility by utilizing location factors as one of the input parameters in a fuzzy logic handover algorithm. The third goal is to minimize false handover alarms caused by sudden fluctuations of parameters by monitoring the trend of fuzzy logic outputs for a period of time before making handover decision. In this paper, we use RSSI, speed and distance as the input decision criteria of a handover trigger algorithm by means of fuzzy logic. The fuzzy logic output trend is monitored for a period of tim...

  1. Satellite Image Time Series Decomposition Based on EEMD

    Directory of Open Access Journals (Sweden)

    Yun-long Kong

    2015-11-01

    Full Text Available Satellite Image Time Series (SITS have recently been of great interest due to the emerging remote sensing capabilities for Earth observation. Trend and seasonal components are two crucial elements of SITS. In this paper, a novel framework of SITS decomposition based on Ensemble Empirical Mode Decomposition (EEMD is proposed. EEMD is achieved by sifting an ensemble of adaptive orthogonal components called Intrinsic Mode Functions (IMFs. EEMD is noise-assisted and overcomes the drawback of mode mixing in conventional Empirical Mode Decomposition (EMD. Inspired by these advantages, the aim of this work is to employ EEMD to decompose SITS into IMFs and to choose relevant IMFs for the separation of seasonal and trend components. In a series of simulations, IMFs extracted by EEMD achieved a clear representation with physical meaning. The experimental results of 16-day compositions of Moderate Resolution Imaging Spectroradiometer (MODIS, Normalized Difference Vegetation Index (NDVI, and Global Environment Monitoring Index (GEMI time series with disturbance illustrated the effectiveness and stability of the proposed approach to monitoring tasks, such as applications for the detection of abrupt changes.

  2. Time trends in population prevalence of eating disorder behaviors and their relationship to quality of life.

    Directory of Open Access Journals (Sweden)

    Deborah Mitchison

    Full Text Available OBJECTIVE: To examine temporal trends in the burden of eating disorder (ED features, as estimated by the composite of their prevalence and impact upon quality of life (QoL over a period of 10 years. METHODOLOGY: Representative samples of 3010 participants in 1998 and 3034 participants in 2008 from the South Australian adult population were assessed for endorsement of ED features (objective binge eating, extreme dieting, and purging were assessed in both years; subjective binge eating and extreme weight/shape concerns were also assessed in 2008 and QoL using the Medical Outcomes Study Short Form (SF-36. PRINCIPAL FINDINGS: From 1998 to 2008 significant increases in the prevalence of objective binge eating (2.7% to 4.9%, p0.05. Multiple linear regressions found that in 1998 only objective binge eating significantly predicted scores on the mental health summary scale of the SF-36; however, in 2008 extreme weight/shape concerns, extreme dieting, and subjective binge eating were also significant predictors. Objective binge eating and extreme dieting were significant predictors of scores on the physical health summary scale of the SF-36 in both 1998 and 2008. CONCLUSIONS AND SIGNIFICANCE: The prevalence of ED behaviors increased between 1998 and 2008, while their impact on QoL remained stable. This suggests an overall increase in the burden of disordered eating from 1998 to 2008. Given that binge eating and extreme dieting predict impairment in QoL, the necessity of interventions to prevent both under- and over-eating is reinforced.

  3. Time trends of viral meningitis among young adults in Israel: 1978-2012.

    Science.gov (United States)

    Levine, Hagai; Mimouni, Daniel; Zurel-Farber, Anat; Zahavi, Alon; Molina-Hazan, Vered; Bar-Zeev, Yael; Huerta-Hartal, Michael

    2014-07-01

    Viral meningitis (VM) is a medical condition of public health concern, as it is a common sporadic and epidemic illness. However, there is limited data on the epidemiology of VM. The purpose of this study was to analyze long-term and seasonal trends of VM in a young adult military population. VM is a obligatory notifiable disease in the Israel Defense Forces. For the present study, the archives of the Army Health Branch were reviewed for all cases of VM from January 1, 1978 to December 31, 2012, and the annual, monthly, and seasonal rates were calculated. The annual incidence over the 35-year period showed a high peak every 3-5 years followed by a quiescent period of 2-3 years, reaching as high as 58.4 per 100,000 in 1980 and as low as 3.0 per 100,000 in 2005. This cyclic pattern has diminished over the last decade, reflected by a decline in mean incidence (10.46 per 100,000 in 2003-2012 compared to 19.79 per 100,000 in 1978-2002). Average monthly rates ranged from 1.0 cases per 100,000 soldiers in January/February to 2.2 per 100,000 in July/August. The difference in average rates between winter (1.2 cases per 100,000) and summer (1.9 cases per 100,000) was statistically significant (p viral causes of meningitis may spare patients unnecessary treatment while prompting the introduction of public health interventions and control measures, especially in crowded settings.

  4. Predicting magnetostructural trends in equiatomic FeRh-based ternary systems

    Science.gov (United States)

    Barua, Radhika; Jimenez-Villacorta, Felix; Lewis, Laura; Nanomagnetism Group Team

    2013-03-01

    A phenomenological model is proposed to predict the influence of elemental substitution on the magnetostructural transition temperatures and Curie temperatures of nominally-equiatomic FeRh-based compounds with the B2 (CsCl)-type crystal structure. Clear trends in the characteristic magnetic transition temperatures, as reported in the literature, are found as a function of the averaged weighted valence band electrons ((s + d) electrons/atom) in compounds of composition Fe(Rh1-xMx) or (Fe1-xMx) Rh (M = 3 d, 4 d or 5 d transition metals). Substitution of 3 d or 4 d elements (FeRh causes the magnetostructural transition temperature Tt to increase to a maximum around a critical valence band electron concentration of 8.5 electrons/atom and then decrease. Substitution of 5 d transition metal atoms echoes this trend but shifts it to higher transition temperatures. These data and associated trends allow deductions that the stability of the ground state antiferromagnetic phase of the FeRh-based system depends both on the size of the constituent atoms as well as the character of the valence electrons. Research was performed under the auspices of the U.S. Dept. of Energy, Division of Materials Science, Office of Basic Energy Sciences (Contract No. DE-SC0005250).

  5. Time trends and correlates of late presentation for HIV care in Northern Greece during the decade 2000 to 2010

    Directory of Open Access Journals (Sweden)

    Simeon Metallidis

    2012-10-01

    Full Text Available Background: The aim of our study was to assess the extent of late presentation for HIV care in Northern Greece during the period 2000 to 2010 and to explore correlations aiming to provide guidance for future interventions. Methods: HIV-positive patients with no prior history of HIV care at presentation and with a CD4 T cell count within three months from the first confirmatory Western blot result were eligible for this study. Late presentation and advanced HIV disease were defined in concordance with the recommendations of the European Late Presenter Consensus working group. Time trends in presentation status and risk factors linked to late presentation and advanced HIV disease were identified in multivariable logistic regression models. Additional analyses after multiple imputation of missing values were performed to assess the robustness of our findings. Results: The status at presentation was evaluated for 631 eligible HIV-positive individuals. Overall, 52.5% (95% CI: 48.6% to 56.4% of patients presented late for HIV care and 31.2% (95% CI: 27.6% to 34.8% presented with advanced HIV disease. Time trends were consistent with an improvement in the presentation status of our study population (p<0.001. Risk factors associated with late presentation in multivariable logistic regression were intravenous drug use, heterosexual HIV transmission, immigrant status and age at diagnosis. Conclusions: Despite the trend for improvement, a significant proportion of newly diagnosed HIV-positive patients present late for care. Targeted interventions with focus on social groups such as the elderly, persons who inject drugs, immigrants and individuals at risk for heterosexual HIV transmission are mandated.

  6. Visibility Graph Based Time Series Analysis.

    Directory of Open Access Journals (Sweden)

    Mutua Stephen

    Full Text Available Network based time series analysis has made considerable achievements in the recent years. By mapping mono/multivariate time series into networks, one can investigate both it's microscopic and macroscopic behaviors. However, most proposed approaches lead to the construction of static networks consequently providing limited information on evolutionary behaviors. In the present paper we propose a method called visibility graph based time series analysis, in which series segments are mapped to visibility graphs as being descriptions of the corresponding states and the successively occurring states are linked. This procedure converts a time series to a temporal network and at the same time a network of networks. Findings from empirical records for stock markets in USA (S&P500 and Nasdaq and artificial series generated by means of fractional Gaussian motions show that the method can provide us rich information benefiting short-term and long-term predictions. Theoretically, we propose a method to investigate time series from the viewpoint of network of networks.

  7. Incidence and Trends in Psychopathology Symptoms over Time in Adults with Severe to Profound Intellectual Disability

    Science.gov (United States)

    Horovitz, Max; Matson, Johnny L.; Sipes, Megan; Shoemaker, Mary; Belva, Brian; Bamburg, Jay W.

    2011-01-01

    Individuals with intellectual disability (ID) have a high risk for developing comorbid psychopathology. While researchers have shown that symptoms of psychopathology remain relatively stable in children with ID over time, little research has been conducted to demonstrate symptom stability for adults with ID. Incidence of psychopathology symptoms…

  8. Time Series Prediction Based on Chaotic Attractor

    Institute of Scientific and Technical Information of China (English)

    LIKe-Ping; CHENTian-Lun; GAOZi-You

    2003-01-01

    A new prediction technique is proposed for chaotic time series. The usefulness of the technique is that it can kick off some false neighbor points which are not suitable for the local estimation of the dynamics systems. A time-delayed embedding is used to reconstruct the underlying attractor, and the prediction model is based on the time evolution of the topological neighboring in the phase space. We use a feedforward neural network to approximate the local dominant Lyapunov exponent, and choose the spatial neighbors by the Lyapunov exponent. The model is tested for the Mackey-Glass equation and the convection amplitude of lorenz systems. The results indicate that this prediction technique can improve the prediction of chaotic time series.

  9. Time-frequency methods for trend removal in electrochemical noise data

    NARCIS (Netherlands)

    Homborg, A.M.; Tinga, T.; Zhang, X.; Westing, E.P.M. van; Oonincx, P.J.; Wit, J.H.W. de; Mol, J.M.C.

    2012-01-01

    Electrochemical current and potential noise signals in many cases exhibit a DC drift that should be removed prior to further data analysis. The theoretical ability of wavelet analysis and empirical mode decomposition to effectively remove only the DC drift component is evaluated based on their mutua

  10. Time trends in primary-care morbidity, hospitalization and mortality due to pneumonia.

    NARCIS (Netherlands)

    Gageldonk-Lafeber, A.B. van; Bogaerts, M.A.H.; Verheij, R.; Sande, M.A.B. van der

    2009-01-01

    Most studies reporting pneumonia morbidity are restricted to hospitalized patients, although only a minority of pneumonia patients are admitted to hospital. To get a better understanding of the burden of disease in the general population, we conducted a population-based retrospective study to examin

  11. Time trends in the incidence of eating disorders : A primary care study in the Netherlands

    NARCIS (Netherlands)

    van Son, Gabrielle E.; van Hoeken, Daphne; Bartelds, Aad I. M.; van Furth, Eric F.; Hoek, Hans W.

    2006-01-01

    Objective: This Dutch epidemiological study used primary care-based data to examine changes in the incidence of eating disorders in the 1990s compared to the 1980s. Method: A nationwide network of general practitioners, serving a representative sample of the total Dutch population, recorded newly di

  12. Time trends and latitude dependence of uveal and cutaneous malignant melanoma induced by solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moan, J.; Setlow, R.; Cicarma, E.; Porojnicu, A. C.; Grant, W. B.; Juzeniene, A.

    2010-01-01

    In order to evaluate the role of solar radiation in uveal melanoma etiology, the time and latitude dependency of the incidence rates of this melanoma type were studied in comparison with those of cutaneous malignant melanoma (CMM). Norway and several other countries with Caucasian populations were included. There is a marked north - south gradient of the incidence rates of CMM in Norway, with three times higher rates in the south than in the north. No such gradient is found for uveal melanoma. Similar findings have been published for CMM in other Caucasian populations, with the exception of Europe as a whole. In most populations the ratios of uveal melanoma incidence rates to those of CMM tend to decrease with increasing CMM rates. This is also true for Europe, in spite of the fact that in this region there is an inverse latitude gradient of CMM, with higher rates in the north than in the south. In Norway the incidence rates of CMM have increased until about 1990 but have been constant, or even decreased (for young people) after that time, indicating constant or decreasing sun exposure. The uveal melanoma rates have been increasing after 1990. In most other populations the incidence rates of CMM have been increasing until recently while those of uveal melanoma have been decreasing. These data generally support the assumption that uveal melanomas are not generated by ultraviolet (UV) radiation and that solar UV, via its role in vitamin D photosynthesis, may have a protective effect.

  13. Status and trend of NO2 pollution in Indian cities from space based remote sensing

    Directory of Open Access Journals (Sweden)

    ARYA RAMACHANDRAN NAIR

    2015-09-01

    Full Text Available NO2 pollution in Indian cities is a well-known problem requiring adequate analysis and implementation of appropriate control strategies. Advanced space-borne instrument ‘ SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY(SCI AMACHY ’- measurements are proved to be helpful in estimating the tropospheric concentration of NO2 which can meaningfully relate to the ground level pollution. Here, these satellite data are explored to analyse the status and trend in NO2 pollution at ten selected metro cities of India. The appropriate geospatial and statistical methods are employed for the processing and analysis of data. The observed results indicated the status of NO2 pollution in these cities as well as its trend throughout the period 2002 to 2012. This study reports, statistically significant increasing trends in NO2 level at all these cities except one. Also, the influence of climatic seasons on modulating the ambient NO2 level is reflected in all cities. For ensuring the validity of results based on satellite data, a comparison is made between the SCIAMACHY NO2 and ground stations measurements which yielded an agreeable correlation of 0.5.This study demonstrates the applicability of satellite remote sensing for urban air quality monitoring and suggest its usability for other parts of the world where ground station measurements are scarce or not available.

  14. Climate trends and behaviour of drought indices based on precipitation and evapotranspiration in Portugal

    Directory of Open Access Journals (Sweden)

    A. A. Paulo

    2012-05-01

    Full Text Available Distinction between drought and aridity is crucial to understand water scarcity processes. Drought indices are used for drought identification and drought severity characterisation. The Standardised Precipitation Index (SPI and the Palmer Drought Severity Index (PDSI are the most known drought indices. In this study, they are compared with the modified PDSI for Mediterranean conditions (MedPDSI and the Standardised Precipitation Evapotranspiration Index (SPEI. MedPDSI results from the soil water balance of an olive crop, thus real evapotranspiration is considered, while SPEI uses potential (climatic evapotranspiration. Similarly to the SPI, SPEI can be computed at various time scales. Aiming at understanding possible impacts of climate change, prior to compare the drought indices, a trend analysis relative to precipitation and temperature in 27 weather stations of Portugal was performed for the period 1941 to 2006. A trend for temperature increase was observed for some weather stations and trends for decreasing precipitation in March and increasing in October were also observed for some locations. Comparisons of the SPI and SPEI at 9- and 12-month time scales, the PDSI and MedPDSI were performed for the same stations and period. SPI and SPEI produce similar results for the same time scales concerning drought occurrence and severity. PDSI and MedPDSI correlate well between them and the same happened for SPI and SPEI. PDSI and MedPDSI identify more severe droughts than SPI or SPEI and identify drought occurrence earlier than these indices. This behaviour is likely to be related with the fact that a water balance is performed with PDSI and MedPDSI, which better approaches the supply-demand balance.

  15. Are time-trends of smoking among pregnant immigrant women in Sweden determined by cultural or socioeconomic factors?

    Directory of Open Access Journals (Sweden)

    Eek Frida

    2010-06-01

    Full Text Available Abstract Background The widening socioeconomic gap in smoking during pregnancy remains a challenge to the Swedish antenatal care services. However, the influence of cultural factors in explaining the socioeconomic differences in smoking during pregnancy is not clear among the immigrant women. The aim of this study was to investigate whether the development of smoking prevalence among pregnant immigrant women in Sweden followed the trajectory which could be expected from the stages of the global smoking epidemic model in the women's countries of origin, or not. Methods Delivery data on pregnancies in Sweden from 1982 to 2001 was collected from the Swedish Medical Birth Registry. From a total of 2,224,469 pregnant women during this period, all immigrant pregnant women (n = 234,731 were selected to this study. A logistic regression analysis and attributable fraction were used to investigate the association between smoking during pregnancy and the socioeconomic differences among immigrant women. Results Overall, the prevalence of smoking among pregnant immigrant women decreased from 30.3% in 1982 to 11.0% in 2001, albeit with remarkable differences between educational levels and country of origin. The greatest decline of absolute prevalence was recorded among low educated women (27,9% and among other Nordic countries (17,9%. In relative terms, smoking inequalities increased between educational levels regardless of country of origin. The odds ratios for low educational level for women from other Nordic countries increased from 4.9 (95% CI 4.4-5.4 in 1982 to 13.4 (95% CI 11.2-16.2 in 2001, as compared to women with high education in the same group. Further, the total attributable fraction for educational difference increased from 55% in 1982 to 62% in 2001, demonstrating the strong effect of educational attainment. Conclusions Our hypothesis that the socioeconomic time trend of smoking based on the stage of the world wide tobacco epidemic model

  16. Trend extraction of rail corrugation measured dynamically based on the relevant low-frequency principal components reconstruction

    Science.gov (United States)

    Li, Yanfu; Liu, Hongli; Ma, Ziji

    2016-10-01

    Rail corrugation dynamic measurement techniques are critical to guarantee transport security and guide rail maintenance. During the inspection process, low-frequency trends caused by rail fluctuation are usually superimposed on rail corrugation and seriously affect the assessment of rail maintenance quality. In order to extract and remove the nonlinear and non-stationary trends from original mixed signals, a hybrid model based ensemble empirical mode decomposition (EEMD) and modified principal component analysis (MPCA) is proposed in this paper. Compared with the existing de-trending methods based on EMD, this method first considers low-frequency intrinsic mode functions (IMFs) thought to be underlying trend components that maybe contain some unrelated components, such as white noise and low-frequency signal itself, and proposes to use PCA to accurately extract the pure trends from the IMFs containing multiple components. On the other hand, due to the energy contribution ratio between trends and mixed signals is prior unknown, and the principal components (PCs) decomposed by PCA are arranged in order of energy reduction without considering frequency distribution, the proposed method modifies traditional PCA and just selects relevant low-frequency PCs to reconstruct the trends based on the zero-crossing numbers (ZCN) of each PC. Extensive tests are presented to illustrate the effectiveness of the proposed method. The results show the proposed EEMD-PCA-ZCN is an effective tool for trend extraction of rail corrugation measured dynamically.

  17. Trends and advances in food analysis by real-time polymerase chain reaction.

    Science.gov (United States)

    Salihah, Nur Thaqifah; Hossain, Mohammad Mosharraf; Lubis, Hamadah; Ahmed, Minhaz Uddin

    2016-05-01

    Analyses to ensure food safety and quality are more relevant now because of rapid changes in the quantity, diversity and mobility of food. Food-contamination must be determined to maintain health and up-hold laws, as well as for ethical and cultural concerns. Real-time polymerase chain reaction (RT-PCR), a rapid and inexpensive quantitative method to detect the presence of targeted DNA-segments in samples, helps in determining both accidental and intentional adulterations of foods by biological contaminants. This review presents recent developments in theory, techniques, and applications of RT-PCR in food analyses, RT-PCR addresses the limitations of traditional food analyses in terms of sensitivity, range of analytes, multiplexing ability, cost, time, and point-of-care applications. A range of targets, including species of plants or animals which are used as food ingredients, food-borne bacteria or viruses, genetically modified organisms, and allergens, even in highly processed foods can be identified by RT-PCR, even at very low concentrations. Microfluidic RT-PCR eliminates the separate sample-processing step to create opportunities for point-of-care analyses. We also cover the challenges related to using RT-PCR for food analyses, such as the need to further improve sample handling.

  18. Trends and advances in food analysis by real-time polymerase chain reaction.

    Science.gov (United States)

    Salihah, Nur Thaqifah; Hossain, Mohammad Mosharraf; Lubis, Hamadah; Ahmed, Minhaz Uddin

    2016-05-01

    Analyses to ensure food safety and quality are more relevant now because of rapid changes in the quantity, diversity and mobility of food. Food-contamination must be determined to maintain health and up-hold laws, as well as for ethical and cultural concerns. Real-time polymerase chain reaction (RT-PCR), a rapid and inexpensive quantitative method to detect the presence of targeted DNA-segments in samples, helps in determining both accidental and intentional adulterations of foods by biological contaminants. This review presents recent developments in theory, techniques, and applications of RT-PCR in food analyses, RT-PCR addresses the limitations of traditional food analyses in terms of sensitivity, range of analytes, multiplexing ability, cost, time, and point-of-care applications. A range of targets, including species of plants or animals which are used as food ingredients, food-borne bacteria or viruses, genetically modified organisms, and allergens, even in highly processed foods can be identified by RT-PCR, even at very low concentrations. Microfluidic RT-PCR eliminates the separate sample-processing step to create opportunities for point-of-care analyses. We also cover the challenges related to using RT-PCR for food analyses, such as the need to further improve sample handling. PMID:27407185

  19. Time-driven activity-based costing.

    Science.gov (United States)

    Kaplan, Robert S; Anderson, Steven R

    2004-11-01

    In the classroom, activity-based costing (ABC) looks like a great way to manage a company's limited resources. But executives who have tried to implement ABC in their organizations on any significant scale have often abandoned the attempt in the face of rising costs and employee irritation. They should try again, because a new approach sidesteps the difficulties associated with large-scale ABC implementation. In the revised model, managers estimate the resource demands imposed by each transaction, product, or customer, rather than relying on time-consuming and costly employee surveys. This method is simpler since it requires, for each group of resources, estimates of only two parameters: how much it costs per time unit to supply resources to the business's activities (the total overhead expenditure of a department divided by the total number of minutes of employee time available) and how much time it takes to carry out one unit of each kind of activity (as estimated or observed by the manager). This approach also overcomes a serious technical problem associated with employee surveys: the fact that, when asked to estimate time spent on activities, employees invariably report percentages that add up to 100. Under the new system, managers take into account time that is idle or unused. Armed with the data, managers then construct time equations, a new feature that enables the model to reflect the complexity of real-world operations by showing how specific order, customer, and activity characteristics cause processing times to vary. This Tool Kit uses concrete examples to demonstrate how managers can obtain meaningful cost and profitability information, quickly and inexpensively. Rather than endlessly updating and maintaining ABC data,they can now spend their time addressing the deficiencies the model reveals: inefficient processes, unprofitable products and customers, and excess capacity. PMID:15559451

  20. Time-driven activity-based costing.

    Science.gov (United States)

    Kaplan, Robert S; Anderson, Steven R

    2004-11-01

    In the classroom, activity-based costing (ABC) looks like a great way to manage a company's limited resources. But executives who have tried to implement ABC in their organizations on any significant scale have often abandoned the attempt in the face of rising costs and employee irritation. They should try again, because a new approach sidesteps the difficulties associated with large-scale ABC implementation. In the revised model, managers estimate the resource demands imposed by each transaction, product, or customer, rather than relying on time-consuming and costly employee surveys. This method is simpler since it requires, for each group of resources, estimates of only two parameters: how much it costs per time unit to supply resources to the business's activities (the total overhead expenditure of a department divided by the total number of minutes of employee time available) and how much time it takes to carry out one unit of each kind of activity (as estimated or observed by the manager). This approach also overcomes a serious technical problem associated with employee surveys: the fact that, when asked to estimate time spent on activities, employees invariably report percentages that add up to 100. Under the new system, managers take into account time that is idle or unused. Armed with the data, managers then construct time equations, a new feature that enables the model to reflect the complexity of real-world operations by showing how specific order, customer, and activity characteristics cause processing times to vary. This Tool Kit uses concrete examples to demonstrate how managers can obtain meaningful cost and profitability information, quickly and inexpensively. Rather than endlessly updating and maintaining ABC data,they can now spend their time addressing the deficiencies the model reveals: inefficient processes, unprofitable products and customers, and excess capacity.

  1. Crop Yield Forecasted Model Based on Time Series Techniques

    Institute of Scientific and Technical Information of China (English)

    Li Hong-ying; Hou Yan-lin; Zhou Yong-juan; Zhao Hui-ming

    2012-01-01

    Traditional studies on potential yield mainly referred to attainable yield: the maximum yield which could be reached by a crop in a given environment. The new concept of crop yield under average climate conditions was defined in this paper, which was affected by advancement of science and technology. Based on the new concept of crop yield, the time series techniques relying on past yield data was employed to set up a forecasting model. The model was tested by using average grain yields of Liaoning Province in China from 1949 to 2005. The testing combined dynamic n-choosing and micro tendency rectification, and an average forecasting error was 1.24%. In the trend line of yield change, and then a yield turning point might occur, in which case the inflexion model was used to solve the problem of yield turn point.

  2. Time-space trends in Swedish divorce behaviour, 1911-1974.

    Science.gov (United States)

    Sandström, Glenn

    2011-01-01

    This study examines how the divorce rates in Sweden have varied over time and across different geographical areas during the period 1911-1974, and how these variations can be connected to the political, socio-economic and cultural development in Sweden. The analysis provides empirical support for the hypothesis that increased divorce rates have been the result of changes in the structural conditions that determine the degree of economic interdependence between spouses. There is a strong connection between the degree of urbanization and the divorce rate on a regional level for the entire research period. The statistical analysis of the regional data indicates that these patterns are connected to the more diversified economy that has developed in urban settings, in the form of a more qualified labour market and higher wages for females. These characteristics resulted in a faster and more pronounced reduction of economic interdependence between spouses, which made divorce more attainable in these areas as compared with rural settings.

  3. Current and future trends in psychology and chronic pain: time for a change?

    Science.gov (United States)

    McCracken, Lance M; Marin, Francisco Montesinos

    2014-03-01

    Psychological approaches to chronic pain have produced significant success and are widely accepted. Yet it can be difficult for those outside the field to understand the many different variables, processes and methods that are a part of these approaches. This is partly because these approaches are characterized by a wide variety of models, each with its own primary focus and background assumptions, and these can change over time. It may be difficult to create greater consistency and integration between currently disparate psychological approaches, but there may be advantages to doing so. This integration could be helped by an appropriately designed and appropriately organizing theoretical model. It is suggested that what is called the psychological flexibility model could provide such a point of integration.

  4. Current and future trends in psychology and chronic pain: time for a change?

    Science.gov (United States)

    McCracken, Lance M; Marin, Francisco Montesinos

    2014-03-01

    Psychological approaches to chronic pain have produced significant success and are widely accepted. Yet it can be difficult for those outside the field to understand the many different variables, processes and methods that are a part of these approaches. This is partly because these approaches are characterized by a wide variety of models, each with its own primary focus and background assumptions, and these can change over time. It may be difficult to create greater consistency and integration between currently disparate psychological approaches, but there may be advantages to doing so. This integration could be helped by an appropriately designed and appropriately organizing theoretical model. It is suggested that what is called the psychological flexibility model could provide such a point of integration. PMID:24641435

  5. A Time Based Blended Learning Model

    OpenAIRE

    Norberg, Anders; Dziuban, Charles D; Moskal, Patsy M

    2011-01-01

    Purpose – This paper seeks to outline a time-based strategy for blended learning that illustrates course design and delivery by framing students' learning opportunities in synchronous and asynchronous modalities. Design/methodology/approach – This paper deconstructs the evolving components of blended learning in order to identify changes induced by digital technologies for enhancing teaching and learning environments. Findings – This paper hypothesizes that blended learning may be traced back...

  6. Time trends in leisure time physical activity, smoking, alcohol consumption and body mass index in Danish adults with and without COPD

    DEFF Research Database (Denmark)

    Hansen, Henrik; Johnsen, Nina Føns; Molsted, Stig

    2016-01-01

    , alcohol consumption, BMI and sociodemographic characteristics. Participants aged 25 years or older with and without COPD were included in the analyses. RESULTS: In multiple logistic regression analyses, odds ratio (OR) of being physically active in the leisure time in 2010 compared to 2000 was 1.70 (95......BACKGROUND: Promotion of a healthy lifestyle and non-pharmacological interventions in the treatment of chronic obstructive pulmonary disease (COPD) has received great attention in recent decades. The aim of this study was to investigate trends in leisure time physical activity (PA), smoking.......001, and 0.74 kg · m(-2) (0.63-0.86), p physically active, non-smoking and not exceeding the recommended alcohol limits. CONCLUSION: From...

  7. A Study of the Equality of Cable Insulations by comparing aging trend using an Oxidation Induction Time Measurement Test

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyungheum; Bhang, Keugjin; Jeong, Sunchul [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2014-05-15

    Usually, the environmental qualification test is carried out by the cable manufacturer and the test report is presented while the cable manufacturer supplies the tested cables in nuclear power plant. If a cable manufacturer has environmentally qualified a cable for nuclear power plant more than a decade ago and the composition of the cable material is same, is it acceptable to use the old EQ report for recently manufactured cable? Even though the manufacturer insists the composition of the tested cable and recently manufactured cable's material are same, there can some questions or opposing opinions for two cables, tested cable and recently manufactured cable's equality. In this case, how can I determine the equality for the two cables? It is well known method to use FT-IR to determine the similarity of cable materials. FT-IR is easy tool to compare compositions of each material. But FT-IR method is not proper to compare aging trend of these materials. Oxidation induction time(OIT) testing is a technique that can be used to evaluate aging of organic materials and life assessment technique for cables used in nuclear power plants. In this paper, I studied the OIT technique to compare aging trend for the tested cable and recently manufactured cable to determine the equality for the two cables. To study a equality analysis for cable materials, OIT measurement tests were performed for two cable insulation(produced in 1995 and produced in 2013) which were supplied from same manufacturer. The two cables were irradiated up to 40 Mrad to simulate normal 40 years and thermally aged for 144 hours at 170 .deg. C equals to 40 years qualified life at 90 .deg. C. The OIT measurement were made in order to compare aging trends of the '95 cable and the '13 cable, the test were performed for three sequential steps; initial, after Normal Radiation and after Thermal Aging. The OIT measurement results at the temperature of 225 .deg. C showed very similar degradation

  8. Who is using snus? - Time trends, socioeconomic and geographic characteristics of snus users in the ageing Swedish population

    Directory of Open Access Journals (Sweden)

    Norberg Margareta

    2011-12-01

    Full Text Available Abstract Background The prevalence of smoking in Sweden has decreased in recent decades, and is now among the lowest in the world. During the same period, the use of Swedish moist oral snuff, a smokeless tobacco called snus, has increased. Few studies have evaluated time trends of the socioeconomic and geographic characteristics of snus users in Sweden. This paper contributes to filling that gap. Methods This study utilized the Linnaeus Database, which links national registers with comprehensive individual data on socioeconomic status (SES to health data from a large ongoing health survey, the Västerbotten Intervention Programme (VIP. The VIP targets the entire middle-aged population of Västerbotten county at ages 40, 50 and 60 years with yearly cross-sectional surveys including self-reported data on tobacco habits. Time trends of snus use among 92,563 VIP-participants across different areas of residence and smoking groups were investigated graphically. Logistic regression was performed to estimate the associations between SES and geographical variables and current use versus non-use of snus. Results Overall, in parallel to decreasing smoking, the increasing trend of snus use in this middle-aged population continues, particularly in 40-year-olds. In both genders, the highest prevalence of snus use was observed among previous smokers. The prevalence of snus use also increased over time among smokers, and was consistently higher compared to those who had never smoked. Among males - both those who had never smoked and previous smokers - low education (OR 1.21, 95%CI 1.06-1.40 and OR 1.28, 95%CI 1.14-1.43, living alone (OR 1.16, 95%CI 1.07-1.27 and OR 1.13, 95%ci 1.04-1.23, low income and living in rural areas was associated with using snus, while this was not seen among male current smokers. Among women, living alone was associated with using snus irrespective of smoking habits. Among female smokers, the OR for snus use increased with higher

  9. Smart Travel Based on Space-Time Behavior Study

    Institute of Scientific and Technical Information of China (English)

    Chai; Yanwei; Shen; Yue; Ta; Na; Qian; Fang

    2015-01-01

    In view of the significant demands and development trends of urbanization during the 12 th Five-Year Plan period, "smart city" has attracted wide attention as an advanced city development concept in China. Under the circumstance of rapid urbanization, traffic congestion and accessibility defi ciency become major challenges to many Chinese cities, as transportation and travel are closely related to the effi ciency of a city’s operation and the quality of people’s life. As essential part of smart city planning and management, smart travel offers an effective behavior planning countermeasure to reduce the amount of urban traffi c and optimize the space-time distribution of travels and provides an effective technology to enrich the theories and methodologies of urban and transportation planning. Orienting at the practical demand of citizens and focusing on their travel behavior, this paper carries out a discussion on the smart travel framework based on space-time behavior study and analyzes smart travel planning and its policy route from multiple perspectives, including a prediction on travel demand, transportation planning, public policy-making, and urban planning. What’s more, the paper suggests travel services for citizens based on space-time behavior analysis, such as providing personalized information, smart decision-making support, and individual behavior planning.

  10. Time series analysis of trends in malaria cases and deaths at hospitals and the effect of antimalarial interventions, 2001-2011, Ethiopia.

    Directory of Open Access Journals (Sweden)

    Maru Aregawi

    Full Text Available BACKGROUND: The Government of Ethiopia and its partners have deployed artemisinin-based combination therapies (ACT since 2004 and long-lasting insecticidal nets (LLINs since 2005. Malaria interventions and trends in malaria cases and deaths were assessed at hospitals in malaria transmission areas during 2001-2011. METHODS: Regional LLINs distribution records were used to estimate the proportion of the population-at-risk protected by LLINs. Hospital records were reviewed to estimate ACT availability. Time-series analysis was applied to data from 41 hospitals in malaria risk areas to assess trends of malaria cases and deaths during pre-intervention (2001-2005 and post-interventions (2006-2011 periods. FINDINGS: The proportion of the population-at-risk potentially protected by LLINs increased to 51% in 2011. The proportion of facilities with ACTs in stock exceeded 87% during 2006-2011. Among all ages, confirmed malaria cases in 2011 declined by 66% (95% confidence interval [CI], 44-79% and SPR by 37% (CI, 20%-51% compared to the level predicted by pre-intervention trends. In children under 5 years of age, malaria admissions and deaths fell by 81% (CI, 47%-94% and 73% (CI, 48%-86% respectively. Optimal breakpoint of the trendlines occurred between January and June 2006, consistent with the timing of malaria interventions. Over the same period, non-malaria cases and deaths either increased or remained unchanged, the number of malaria diagnostic tests performed reflected the decline in malaria cases, and rainfall remained at levels supportive of malaria transmission. CONCLUSIONS: Malaria cases and deaths in Ethiopian hospitals decreased substantially during 2006-2011 in conjunction with scale-up of malaria interventions. The decrease could not be accounted for by changes in hospital visits, malaria diagnostic testing or rainfall. However, given the history of variable malaria transmission in Ethiopia, more data would be required to exclude the

  11. High temperature garnet growth in New England: regional temperature-time trends revealed

    Science.gov (United States)

    Sullivan, N.; Ostwald, C.; Chu, X.; Baxter, E. F.; Ague, J. J.; Eckert, J. O.

    2013-12-01

    A series of localized ultrahigh-temperature (UHT)/high-temperature (HT) granulite facies regions have been identified within the regional amphibolite facies metamorphic zone of the Central Maine Terrane stretching from north-central New Hampshire, through central Massachusetts, and into northeastern Connecticut. Here, we aim to constrain the age and peak temperature of metamorphism at three localities within this region: Bristol, NH, Phillipston, MA and Willington, CT. Garnet-forming reactions are linked directly to peak metamorphic temperatures through thermodynamic modeling and/or Zr-in-rutile thermometry. Precise garnet geochronology allows us to identify the timing of these peak temperatures, as well as the duration of garnet growth. Geochronologic and thermodynamic work was done on 12 samples collected throughout a ~5 km2 metamorphic 'hotspot' previously identified in Bristol, NH (Chamberlain and Rumble, 1988; Journal of Petrology). The highest temperature assemblage within this hotspot is characterized by the presence of garnet + sillimanite + K-feldspar + cordierite and reached temperatures >820οC. The lowest temperature periphery of the hotspot is characterized by sillimanite + muscovite + K-feldspar + minor garnet and reached a maximum temperature of 650οC. Bulk garnet ages from samples within the hotspot range significantly from at least 400.0 × 2.5 Ma to 352.7 × 1.8 Ma with the youngest ages associated with the lower temperature samples. This collection of ages indicates a prolonged period (~50 Ma) of >650οC temperatures interspersed by period(s) of garnet growth. Zoned garnet geochronology will help reveal whether garnet growth and related heating was continuous or episodic. Further south, in Phillipston, MA, zoned garnet geochronology performed on a 2.5 cm diameter garnet porphyroblast indicates garnet growth spanning 389 - 363 Ma, reaching peak temperatures at the end of that time span of 920-940οC, followed by a younger event recorded in

  12. New trends in InSAR time series analysis for wide area deformation mapping

    Science.gov (United States)

    Hanssen, R. F.; Caro Cuenca, M.; Hooper, A.; Mahapatra, P.; Arikan, M.; Bekaert, D.

    2012-04-01

    Synthetic aperture radar interferometry (InSAR) is a remote sensing technique that is extensively used to measure deformation at the Earth's surface. Although it has proven very successful to estimate small-scale (up to tens of km) deformation phenomena, InSAR still has limitations when applied to study wide areas (hundreds of km). First, radar observations are affected by atmospheric delay and errors in sensor position (also referred to as orbital errors). Both of these translate into large scale signals in InSAR estimations that can be interpreted as a non-existing deformation phenomenon. Second, since InSAR produces deformation maps relative to an area (or pixel) that is part of the observed track, combination of adjacent tracks requires the connection of these relative measurements to a common area or reference point. This operation is, however, non-trivial and is preferably performed in combination with in situ data. In this contribution, we explore different case studies where we address the aforementioned limitations to measure deformation in wide areas. They include the whole country of the Netherlands, the area of El Guerrero in Mexico and the North Anatolian Fault in Turkey. Our initial strategy is to filter out atmospheric and orbital errors assuming they are uncorrelated in time. However, this assumption does not always hold. Therefore, ancillary data, such as GPS and leveling, is also used for a precise estimation of the large scale deformation signal. Furthermore, datum connection is performed with ancillary data as well where different radar tracks and other geodetic data are combined to obtain the final deformation map in a common reference system. We also explore how compact radar transponders can help to tackle the datum connection problem.

  13. 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.

  14. Agenda Trending: Reciprocity and the Predictive Capacity of Social Networking Sites in Intermedia Agenda Setting across Topics over Time

    Directory of Open Access Journals (Sweden)

    Jacob Groshek

    2013-08-01

    Full Text Available In the contemporary converged media environment, agenda setting is being transformed by the dramatic growth of audiences that are simultaneously media users and producers. The study reported here addresses related gaps in the literature by first comparing the topical agendas of two leading traditional media outlets (New York Times and CNN with the most frequently shared stories and trending topics on two widely popular Social Networking Sites (Facebook and Twitter. Time-series analyses of the most prominent topics identify the extent to which traditional media sets the agenda for social media as well as reciprocal agenda-setting effects of social media topics entering traditional media agendas. In addition, this study examines social intermedia agenda setting topically and across time within social networking sites, and in so doing, adds a vital understanding of where traditional media, online uses, and social media content intersect around instances of focusing events, particularly elections. Findings identify core differences between certain traditional and social media agendas, but also within social media agendas that extend from uses examined here. Additional results further suggest important topical and event-oriented limitations upon the predictive capacit of social networking sites to shape traditional media agendas over time.

  15. Analysis of stratospheric NO2 trends above Kiruna using ground-based zenith sky DOAS observations

    Science.gov (United States)

    Gu, Myojeong; Enell, Carl-Fredrik; Hendrick, François; Platt, Ulrich; Pukite, Janis; Raffalski, Uwe; Van Roozendael, Michel; Wagner, Thomas

    2016-04-01

    Stratospheric NO2 not only destroys ozone but acts as a buffer against halogen catalyzed ozone loss by converting halogen species into stable nitrates. To a better understanding of the impacts of stratospheric NO2 and O3 chemistry, we need long-term measurement data. In this study, ground-based zenith sky DOAS has successfully monitored trace gases related to stratospheric ozone chemistry since 1997. In this study, we shows the trend in stratospheric NO2 vertical column densities (VCDs) at Kiruna, Sweden (68.84°N, 20.41°E) as derived from ground-based zenith sky DOAS over the period 1997 to 2015. The results will be compared with satellite data measured from GOME on ERS-2, SCIAMACHY on EnviSAT, and GOME-2 on METOP-A. To calculate the trends, we apply a multiple linear regression model including variables to describe effects caused by the quasi-biennial oscillation (QBO), solar activity, and stratospheric aerosol amount.

  16. Footprint and imprint: an ecologic time-trend analysis of cardiovascular publications in general and specialty journals.

    Science.gov (United States)

    Baldridge, Abigail S; Huffman, Mark D; Bloomfield, Gerald S; Prabhakaran, Dorairaj

    2014-06-01

    Studies have demonstrated strong associations between publication source and citations, as well as investigatory analysis of collaboration effects, in general and medical literature, but are limited to specific journals or short duration of time. This study sought to analyze time trends in cardiovascular research publications in leading general and specialty journals and to determine the association between collaboration and citation index. Cardiovascular publications were retrieved from Web of Knowledge by a cardiovascular bibliometric filter, and annual publication volumes in 8 general and specialty journals were compared. Univariable linear regression models were used to determine global and journal-specific trends for overall publication, cardiovascular publication, proportion of cardiovascular publication, collaboration, and citations. Cardiovascular publications increased (1999 to 2008) by 36% and number of sources by 74%. Volume increased in European Heart Journal (beta: 18.4, 95% confidence interval [CI]: 10.6 to 26.3) and decreased in Circulation (beta: -42.9, 95% CI: -79.3 to -6.5), Annals of Internal Medicine (beta: -1.9, 95% CI: -3.5 to -0.3), and Lancet (beta: -11.2, 95% CI: -14.7 to -7.8). Number of contributing countries increased in 3 journals: BMJ (beta: 0.8, 95% CI: 0.2 to 1.5), European Heart Journal (beta: -1.2, 95% CI: 0.8 to 1.7), and New England Journal of Medicine (beta: 1.6, 95% CI: 0.6 to 2.7). Fraction of collaborative publications increased (beta: 1.1 to 2.9) in all but Annals of Internal Medicine. Collaboration was associated with a higher median actual citation index (p journals. Contribution by country in selected journals was disproportionate and under-represents total cardiovascular research in low- and middle-income countries.

  17. Understanding evapotranspiration trends and their driving mechanisms over the NLDAS domain based on numerical experiments using CLM4.5

    Science.gov (United States)

    Parr, Dana; Wang, Guiling; Fu, Congsheng

    2016-07-01

    Previous studies documented a recent decline of the global terrestrial evapotranspiration (ET) trend, of which the underlying mechanisms are not well understood. Based on experiments using the Community Land Model version 4.5 driven with the North American Land Data Assimilation System phase-2 (NLDAS-2) forcing data, this study investigates the variation and changes of ET trends at the continental scale and the mechanisms underlying these changes. Simulations are conducted over the NLDAS domain including the contiguous U.S. and part of Mexico for the period of 1980-2014. Changes of ET trend are derived based on the two subperiods 1982-1997 and 1998-2008. The strongest signals of trend change, of either sign, are primarily located in dry regimes, where ET is limited by water rather than energy. Sensitivity experiments were performed to isolate the impact of some of the most influential factors on the changing ET trends. Results indicate that trends in wind speed and surface air temperature had negligible impact on the ET trend and its changes within the study domain, and the ET trend and its changes are dominated by changes in precipitation amount. Changes in precipitation characteristics including the frequency and intensity are suggested to have a secondary effect on the ET trend changes through modifying the partitioning of water between infiltration and runoff. These findings are further supported by correlation coefficients between ET and various driving factors. Results from this study may be region specific and therefore may not hold for ET trend changes over the rest of the globe.

  18. Linear Regression Based Real-Time Filtering

    Directory of Open Access Journals (Sweden)

    Misel Batmend

    2013-01-01

    Full Text Available This paper introduces real time filtering method based on linear least squares fitted line. Method can be used in case that a filtered signal is linear. This constraint narrows a band of potential applications. Advantage over Kalman filter is that it is computationally less expensive. The paper further deals with application of introduced method on filtering data used to evaluate a position of engraved material with respect to engraving machine. The filter was implemented to the CNC engraving machine control system. Experiments showing its performance are included.

  19. Trends in ultrashort and ultrahigh power laser pulses based on optical parametric chirped pulse amplification

    International Nuclear Information System (INIS)

    Since the proof-of-principle demonstration of optical parametric amplification to efficiently amplify chirped laser pulses in 1992, optical parametric chirped pulse amplification (OPCPA) became the most promising method for the amplification of broadband optical pulses. In the meantime, we are witnessing an exciting progress in the development of powerful and ultrashort pulse laser systems that employ chirped pulse parametric amplifiers. The output power and pulse duration of these systems have ranged from a few gigawatts to hundreds of terawatts with a potential of tens of petawatts power level. Meanwhile, the output pulse duration based on optical parametric amplification has entered the range of few-optical-cycle field. In this paper, we overview the basic principles, trends in development, and current state of the ultrashort and laser systems based on OPCPA, respectively. (paper)

  20. Non-target time trend screening: a data reduction strategy for detecting emerging contaminants in biological samples

    OpenAIRE

    Plassmann, Merle M.; Tengstrand, Erik; Åberg, K. Magnus; Benskin, Jonathan P.

    2016-01-01

    Non-targeted mass spectrometry-based approaches for detecting novel xenobiotics in biological samples are hampered by the occurrence of naturally fluctuating endogenous substances, which are difficult to distinguish from environmental contaminants. Here, we investigate a data reduction strategy for datasets derived from a biological time series. The objective is to flag reoccurring peaks in the time series based on increasing peak intensities, thereby reducing peak lists to only those which m...

  1. Trends in leisure time physical activity, smoking, body mass index and alcohol consumption in Danish adults with and without diabetes

    DEFF Research Database (Denmark)

    Molsted, Stig; Johnsen, Nina Føns; Snorgaard, Ole

    2014-01-01

    AIMS: In recent decades there has been an increased focus on non-pharmacological treatment of diabetes. The aim of this study was to investigate trends in leisure time physical activity (PA), smoking, body mass index (BMI), and alcohol consumption reported in 2000, 2005 and 2010 by Danish subjects...... with diabetes. METHODS: Data comprised level of leisure time PA (inactive; moderate active; medium active; high active); smoking; BMI; and alcohol consumption, provided by The Danish Health and Morbidity Surveys. Participants older than 45 years with or without diabetes were included from cross...... was reduced from 27.2% to 16.4%, p=0.015, in women with diabetes. In men with diabetes, BMI increased from 27.2 ± 4.0 to 28.6 ± 5.1 kgm(-2), p=0.003, and men who exceeded the maximum recommendation for alcohol consumption increased from 9.4% to 19.0%, p=0.007. The leisure time PA level was reduced...

  2. Gender-based screening for chlamydial infection and divergent infection trends in men and women.

    Directory of Open Access Journals (Sweden)

    Susan M Rogers

    Full Text Available OBJECTIVES: To assess the potential impact of chlamydial screening policy that recommends routine screening of women but not men. METHODS: Population surveys of probability samples of Baltimore adults aged 18 to 35 years in 1997-1998 and 2006-2009 collected biospecimens to estimate trends in undiagnosed chlamydial infection. Survey estimates are compared to surveillance data on diagnosed chlamydial infections reported to the Health Department. RESULTS: Prevalence of undiagnosed chlamydial infection among men increased from 1.6% to 4.0%, but it declined from 4.3% to 3.1% among women (p = 0.028 for test of interaction. The annual (average number of diagnosed infections was substantially higher among women than men in both time periods and increased among both men and women. Undiagnosed infection prevalence was substantially higher among black than non-black adults (4.0% vs 1.2%, p = 0.042 in 1997-98 and 5.5% vs 0.7%, p<0.001 in 2006-09. CONCLUSION: Divergent trends in undiagnosed chlamydial infection by gender parallel divergent screening recommendations that encourage chlamydial testing for women but not for men.

  3. State-space based analysis and forecasting of macroscopic road safety trends in Greece.

    Science.gov (United States)

    Antoniou, Constantinos; Yannis, George

    2013-11-01

    In this paper, macroscopic road safety trends in Greece are analyzed using state-space models and data for 52 years (1960-2011). Seemingly unrelated time series equations (SUTSE) models are developed first, followed by richer latent risk time-series (LRT) models. As reliable estimates of vehicle-kilometers are not available for Greece, the number of vehicles in circulation is used as a proxy to the exposure. Alternative considered models are presented and discussed, including diagnostics for the assessment of their model quality and recommendations for further enrichment of this model. Important interventions were incorporated in the models developed (1986 financial crisis, 1991 old-car exchange scheme, 1996 new road fatality definition) and found statistically significant. Furthermore, the forecasting results using data up to 2008 were compared with final actual data (2009-2011) indicating that the models perform properly, even in unusual situations, like the current strong financial crisis in Greece. Forecasting results up to 2020 are also presented and compared with the forecasts of a model that explicitly considers the currently on-going recession. Modeling the recession, and assuming that it will end by 2013, results in more reasonable estimates of risk and vehicle-kilometers for the 2020 horizon. This research demonstrates the benefits of using advanced state-space modeling techniques for modeling macroscopic road safety trends, such as allowing the explicit modeling of interventions. The challenges associated with the application of such state-of-the-art models for macroscopic phenomena, such as traffic fatalities in a region or country, are also highlighted. Furthermore, it is demonstrated that it is possible to apply such complex models using the relatively short time-series that are available in macroscopic road safety analysis.

  4. State-space based analysis and forecasting of macroscopic road safety trends in Greece.

    Science.gov (United States)

    Antoniou, Constantinos; Yannis, George

    2013-11-01

    In this paper, macroscopic road safety trends in Greece are analyzed using state-space models and data for 52 years (1960-2011). Seemingly unrelated time series equations (SUTSE) models are developed first, followed by richer latent risk time-series (LRT) models. As reliable estimates of vehicle-kilometers are not available for Greece, the number of vehicles in circulation is used as a proxy to the exposure. Alternative considered models are presented and discussed, including diagnostics for the assessment of their model quality and recommendations for further enrichment of this model. Important interventions were incorporated in the models developed (1986 financial crisis, 1991 old-car exchange scheme, 1996 new road fatality definition) and found statistically significant. Furthermore, the forecasting results using data up to 2008 were compared with final actual data (2009-2011) indicating that the models perform properly, even in unusual situations, like the current strong financial crisis in Greece. Forecasting results up to 2020 are also presented and compared with the forecasts of a model that explicitly considers the currently on-going recession. Modeling the recession, and assuming that it will end by 2013, results in more reasonable estimates of risk and vehicle-kilometers for the 2020 horizon. This research demonstrates the benefits of using advanced state-space modeling techniques for modeling macroscopic road safety trends, such as allowing the explicit modeling of interventions. The challenges associated with the application of such state-of-the-art models for macroscopic phenomena, such as traffic fatalities in a region or country, are also highlighted. Furthermore, it is demonstrated that it is possible to apply such complex models using the relatively short time-series that are available in macroscopic road safety analysis. PMID:23579105

  5. Time Trend of the Effect the Information Disclosure Quality on the Cost of Equity Capital——An Empirical Study Based on Entropy Measuring of Chinese Listed Companies%信息披露质量对股权融资成本影响的时间趋势——基于熵权测度的我国上市公司的实证研究

    Institute of Scientific and Technical Information of China (English)

    杨红; 杨淑娥; 张鹏

    2012-01-01

    基于对经济时间轴的延伸分析和熵权测度方法,实证研究了信息披露质量对股权融资成本影响的时间特征,结果表明,上市公司信息披露质量与当期的股权融资成本不相关,与其后第一期(下期)、第二期的股权融资成本负相关。稳定性研究还发现,上市公司信息披露质量与当期股权融资成本不相关的结论在样本较少的情况下稳定性不高,而与其后第一期(下期)、第二期股权融资成本负相关的结论具有较强的稳定性。%Based on the extended analysis of the economic time line and the entropy measuring,this paper makes an empirical analysis about the time trend of the effect the information disclosure quality on the cost of equity capital.The study finds that the current information disclosure quality is not relevant with its current cost of equity capital but are significantly relevant with its next first,second stages cost of equity capital and the signs are all negative.The stability test also suggests that the current information disclosure quality is not relevant with its current cost of equity capital but this relationship is unstable in smaller samples circumstances while is significantly relevant with its next first,second stages cost of equity capital and these negative relationships have strong stability.

  6. Current status and trends in performance-based risk-sharing arrangements between healthcare payers and medical product manufacturers.

    Science.gov (United States)

    Carlson, Josh J; Gries, Katharine S; Yeung, Kai; Sullivan, Sean D; Garrison, Louis P

    2014-06-01

    Our objective was to identify and characterize publicly available cases and related trends for performance-based risk-sharing arrangements (PBRSAs). We performed a review of PBRSAs over the past 20 years (1993-2013) using available databases and reports from colleagues and healthcare experts. These were categorized according to a previously published taxonomy of scheme types and assessed in terms of the underlying product and market attributes for each scheme. Macro-level trends were identified related to the timing of scheme adoption, countries involved, types of arrangements, and product and market factors. Our search yielded 148 arrangements. From this set, 65 arrangements included a coverage with an evidence development component, 20 included a conditional treatment continuation component, 54 included a performance-linked reimbursement component, and 42 included a financial utilization component. Each type of scheme addresses fundamental uncertainties that exist when products enter the market. The pace of adoption appears to be slowing, but new countries continue to implement PBRSAs. Over this 20-year period, there has been a consistent movement toward arrangements that minimize administrative burden. In conclusion, the pace of PBRSA adoption appears to be slowing but still has traction in many health systems. These remain a viable coverage and reimbursement mechanism for a wide range of medical products. The long-term viability and growth of these arrangements will rest in the ability of the parties to develop mutually beneficial arrangements that entail minimal administrative burden in their development and implementation. PMID:24664994

  7. Time- versus Competency-Based Residency Training.

    Science.gov (United States)

    Nguyen, Vu T; Losee, Joseph E

    2016-08-01

    Graduate medical education is at the brink of a paradigm shift in educating the next generation of physicians. Over 100 years ago, the Flexner report helped usher in the Halstedian residency, based on timed exposure and knowledge assessment as the cornerstones of medical education. The addition of operative case logs and respective board examinations to the current model of surgical education has served to establish practice minimums; however, they do not provide any assessment of actual operative capability or clinical competence. Although these facets have been tempered over time, one could argue that they currently exist only as surrogates for the true goal of all graduate medical education: the development of competent, graduating physicians, capable of independent and ethical practice. There now exists a growing body of evidence that competency-based medical education is this century's Flexnerian revolution. By the objective, subjective, and global assessment of competence, it is thought that we can more effectively and efficiently educate our trainees, provide much needed accountability to our individual patients and to the public as a whole, and establish a lasting model of self-motivated, lifelong learning. PMID:27465174

  8. Time- versus Competency-Based Residency Training.

    Science.gov (United States)

    Nguyen, Vu T; Losee, Joseph E

    2016-08-01

    Graduate medical education is at the brink of a paradigm shift in educating the next generation of physicians. Over 100 years ago, the Flexner report helped usher in the Halstedian residency, based on timed exposure and knowledge assessment as the cornerstones of medical education. The addition of operative case logs and respective board examinations to the current model of surgical education has served to establish practice minimums; however, they do not provide any assessment of actual operative capability or clinical competence. Although these facets have been tempered over time, one could argue that they currently exist only as surrogates for the true goal of all graduate medical education: the development of competent, graduating physicians, capable of independent and ethical practice. There now exists a growing body of evidence that competency-based medical education is this century's Flexnerian revolution. By the objective, subjective, and global assessment of competence, it is thought that we can more effectively and efficiently educate our trainees, provide much needed accountability to our individual patients and to the public as a whole, and establish a lasting model of self-motivated, lifelong learning.

  9. Time Trends in Incidence and Mortality of Acute Myocardial Infarction, and All-Cause Mortality following a Cardiovascular Prevention Program in Sweden.

    Directory of Open Access Journals (Sweden)

    Gunilla Journath

    Full Text Available In 1988, a cardiovascular prevention program which combined an individual and a population-based strategy was launched within primary health-care in Sollentuna, a municipality in Stockholm County. The aim of this study was to investigate time trends in the incidence of and mortality from acute myocardial infarction and all-cause mortality in Sollentuna compared with the rest of Stockholm County during a period of two decades following the implementation of a cardiovascular prevention program.The average population in Sollentuna was 56,589 (49% men and in Stockholm County (Sollentuna included 1,795,504 (49% men during the study period of 1987-2010. Cases of hospitalized acute myocardial infarction and death were obtained for the population of Sollentuna and the rest of Stockholm County using national registries of hospital discharges and deaths. Acute myocardial infarction incidence and mortality were estimated using the average population of Sollentuna and Stockholm in 1987-2010.During the observation period, the incidence of acute myocardial infarction decreased more in Sollentuna compared with the rest of Stockholm County in women (-22% vs. -7%; for difference in slope <0.05. There was a trend towards a greater decline in Sollentuna compared to the rest of Stockholm County in the incidence of acute myocardial infarction (in men, acute myocardial mortality, and all-cause mortality but the differences were not significant.During a period of steep decline in acute myocardial infarction incidence and mortality in Stockholm County the municipality of Sollentuna showed a stronger trend in women possibly compatible with favorable influence of a cardiovascular prevention program.ClinicalTrials.gov NCT02212145.

  10. Current trends in Finnish drug abuse: Wastewater based epidemiology combined with other national indicators.

    Science.gov (United States)

    Kankaanpää, Aino; Ariniemi, Kari; Heinonen, Mari; Kuoppasalmi, Kimmo; Gunnar, Teemu

    2016-10-15

    No single measure is able to provide a complete picture of population- or community-level drug abuse and its current trends. Therefore, a multi-indicator approach is needed. The aim of this study was to combine wastewater-based epidemiology (WBE) with data from other national indicators, namely driving under the influence of drugs (DUID) statistics, drug seizures, and drug use surveys. Furthermore, drug market size estimates and a comparison of confiscated drugs to drugs actually consumed by users were performed using the WBE approach. Samples for wastewater analysis were collected during one-week sampling periods in 2012, 2014 and 2015, with a maximum of 14 cities participating. The samples were analysed with a validated ultra-high-performance liquid chromatography-mass spectrometric (UHPLC-MS/MS) methodology for various common drugs of abuse. The results were then compared with data from other national indicators available. Joint interpretation of the data shows that the use of amphetamine and MDMA has increased in Finland from 2012 to 2014. A similar trend was also observed for cocaine, although its use remains at a very low level compared to many other European countries. Heroin was practically absent from the Finnish drug market during the study period. The retail market for the most common stimulant drugs were estimated to have been worth EUR 70 million for amphetamine and around EUR 10 million for both methamphetamine and cocaine, in 2014 in Finland. PMID:27335163

  11. Travel-time-based thermal tracer tomography

    Science.gov (United States)

    Somogyvári, Márk; Bayer, Peter; Brauchler, Ralf

    2016-05-01

    Active thermal tracer testing is a technique to get information about the flow and transport properties of an aquifer. In this paper we propose an innovative methodology using active thermal tracers in a tomographic setup to reconstruct cross-well hydraulic conductivity profiles. This is facilitated by assuming that the propagation of the injected thermal tracer is mainly controlled by advection. To reduce the effects of density and viscosity changes and thermal diffusion, early-time diagnostics are used and specific travel times of the tracer breakthrough curves are extracted. These travel times are inverted with an eikonal solver using the staggered grid method to reduce constraints from the pre-defined grid geometry and to improve the resolution. Finally, non-reliable pixels are removed from the derived hydraulic conductivity tomograms. The method is applied to successfully reconstruct cross-well profiles as well as a 3-D block of a high-resolution fluvio-aeolian aquifer analog data set. Sensitivity analysis reveals a negligible role of the injection temperature, but more attention has to be drawn to other technical parameters such as the injection rate. This is investigated in more detail through model-based testing using diverse hydraulic and thermal conditions in order to delineate the feasible range of applications for the new tomographic approach.

  12. Time trends in the association of ESRD incidence with area-level poverty in the US population.

    Science.gov (United States)

    Garrity, Bridget H; Kramer, Holly; Vellanki, Kavitha; Leehey, David; Brown, Julia; Shoham, David A

    2016-01-01

    The objective of this study was to examine the temporal trends of the association between area-level poverty status and end-stage renal disease (ESRD) incidence. We hypothesized that the association between area-level poverty status and ESRD incidence has increased significantly over time. Patient data from the United States Renal Data System were linked with data from the 2000 and 2010 US census. Area-level poverty was defined as living in a zip code-defined area with ≥20% of households living below the federal poverty line. Negative binomial regression models were created to examine the association between area-level poverty status and ESRD incidence by time period in the US adult population while simultaneously adjusting for the distribution of age, sex, and race/ethnicity within a zip code. Time was categorized as January 1, 1995 through December 31, 2004 (Period 1) and January 1, 2005 through December 31, 2010 (Period 2). The percentage of adults initiating dialysis with area-level poverty increased from 27.4% during Period 1 to 34.0% in Period 2. After accounting for the distribution of age, sex, and race/ethnicity within a zip code, area-level poverty status was associated with a 1.24 (95% confidence interval [CI] 1.22, 1.25)-fold higher ESRD incidence. However, this association differed by time period with 1.04-fold (95% CI 1.02, 1.05) higher ESRD incidence associated with poverty status for Period 2 compared with the association between ESRD and poverty status in Period 1. Area-level poverty and its association with ESRD incidence is not static over time. PMID:26094617

  13. Time trends in the association of ESRD incidence with area-level poverty in the US population.

    Science.gov (United States)

    Garrity, Bridget H; Kramer, Holly; Vellanki, Kavitha; Leehey, David; Brown, Julia; Shoham, David A

    2016-01-01

    The objective of this study was to examine the temporal trends of the association between area-level poverty status and end-stage renal disease (ESRD) incidence. We hypothesized that the association between area-level poverty status and ESRD incidence has increased significantly over time. Patient data from the United States Renal Data System were linked with data from the 2000 and 2010 US census. Area-level poverty was defined as living in a zip code-defined area with ≥20% of households living below the federal poverty line. Negative binomial regression models were created to examine the association between area-level poverty status and ESRD incidence by time period in the US adult population while simultaneously adjusting for the distribution of age, sex, and race/ethnicity within a zip code. Time was categorized as January 1, 1995 through December 31, 2004 (Period 1) and January 1, 2005 through December 31, 2010 (Period 2). The percentage of adults initiating dialysis with area-level poverty increased from 27.4% during Period 1 to 34.0% in Period 2. After accounting for the distribution of age, sex, and race/ethnicity within a zip code, area-level poverty status was associated with a 1.24 (95% confidence interval [CI] 1.22, 1.25)-fold higher ESRD incidence. However, this association differed by time period with 1.04-fold (95% CI 1.02, 1.05) higher ESRD incidence associated with poverty status for Period 2 compared with the association between ESRD and poverty status in Period 1. Area-level poverty and its association with ESRD incidence is not static over time.

  14. Bayes Factor based on the Trend Test Incorporating Hardy-Weinberg Disequilibrium: More Powerful to Detect Genetic Association

    OpenAIRE

    Xu, Jinfeng; Yuan, Ao; Zheng, Gang

    2012-01-01

    In the analysis of case-control genetic association, the trend test and Pearson’s test are the two most commonly used tests. In genome-wide association studies (GWAS), Bayes factor is a useful tool to support significant p-values, and a better measure than p-value when results are compared across studies with different sample sizes. When reporting the p-value of the trend test, we propose a Bayes factor directly based on the trend test. To improve the power to detect association under recessi...

  15. Bayes Factor Based on the Trend Test Incorporating Hardy–Weinberg Disequilibrium: More Power to Detect Genetic Association

    OpenAIRE

    Xu, J.; Yuan, A.; Zheng, G.

    2012-01-01

    In the analysis of case‐control genetic association, the trend test and Pearson’s test are the two most commonly used tests. In genome‐wide association studies (GWAS), Bayes factor (BF) is a useful tool to support significant ‐values, and a better measure than ‐value when results are compared across studies with different sample sizes. When reporting the ‐value of the trend test, we propose a BF directly based on the trend test. To improve the power to detect association under recessive or do...

  16. Temporal Trends in Overweight and Obesity, Physical Activity and Screen Time among Czech Adolescents from 2002 to 2014: A National Health Behaviour in School-Aged Children Study.

    Science.gov (United States)

    Sigmund, Erik; Sigmundová, Dagmar; Badura, Petr; Kalman, Michal; Hamrik, Zdenek; Pavelka, Jan

    2015-09-01

    This study examines trends in overweight and obesity, physical activity (PA) and screen time (ST) among Czech adolescents over a recent 12-year study period. Nationally representative samples consisted of 19,940 adolescents (9760 boys and 10,180 girls) aged 10.5-16.5 years from the Czech Health Behaviour in School-aged Children (HBSC) questionnaire-based surveys conducted in 2002, 2006, 2010 and 2014. Trends in the prevalence of overweight/obesity, meeting the recommendations for moderate-to-vigorous PA (MVPA) (≥60 min per day of MVPA) and excessive ST (>2 h per day) were estimated using logistic regression. Significant increases (p obesity between the years 2002 and 2014 were evident for both adolescent boys (18.3%(2002)-24.8%(2014)) and girls (8.3%(2002)-11.9%(2014)). Compared to 2002, in 2014 significant decreases (p obesity with concomitant decreases in PA provide evidence in support of the current and upcoming efforts of government and commercial organizations in implementing interventions aimed at reducing excessive body weight among Czech adolescents.

  17. Time trends of polybrominated diphenyl ethers in East China Seas: Response to the booming of PBDE pollution industry in China.

    Science.gov (United States)

    Li, Yuanyuan; Lin, Tian; Hu, Limin; Feng, Jialiang; Guo, Zhigang

    2016-01-01

    The East China Seas (ECSs) are the receptors of the land-based persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs) mainly from China through atmospheric deposition driven by the East Asian winter monsoon and fluvial discharge (e.g., Yangtze River and Yellow River), making the offshore sediments to be a good proxy to reconstruct history of those pollutants in China. In this work, four well-placed sediment cores were extracted from the mud areas in the ECSs, and the (210)Pb-dated cores were analyzed to yield historical concentration profiles of PBDEs in the area. The results showed that there was a persistent increase from 1970s and almost no clear sign in the decline of PBDEs until recently in China. More importantly, there was a faster increase of PBDEs from 1990s in China; while this period was just shown as gradually leveling off or even declining trends in developed countries. The persistently increasing trend of PBDEs in China since 1990s could be largely due to the booming of the manufacturing industry and unexpectedly transfer of PBDE pollution from developed countries to China. Besides, the relative high concentrations and fluxes of PBDEs in the core from coastal ECS located near a well-known electrical/electronic waste (e-waste) recycling area suggests an important contribution of PBDE emissions from recycling centers of e-waste in China. Although efforts in environmental monitoring of PBDE contamination have been substantially increased over the last decade, China is still lagging behind in terms of nationwide regulation of PBDE usage and treatment of disposal PBDE-containing products. PMID:27179303

  18. Trends and sensitivities of low streamflow extremes to discharge timing and magnitude in Pacific Northwest mountain streams

    Science.gov (United States)

    Kormos, Patrick R.; Luce, Charles H.; Wenger, Seth J.; Berghuijs, Wouter R.

    2016-07-01

    Path analyses of historical streamflow data from the Pacific Northwest indicate that the precipitation amount has been the dominant control on the magnitude of low streamflow extremes compared to the air temperature-affected timing of snowmelt runoff. The relative sensitivities of low streamflow to precipitation and temperature changes have important implications for adaptation planning because global circulation models produce relatively robust estimates of air temperature changes but have large uncertainties in projected precipitation amounts in the Pacific Northwest U.S. Quantile regression analyses indicate that low streamflow extremes from the majority of catchments in this study have declined from 1948 to 2013, which may significantly affect terrestrial and aquatic ecosystems, and water resource management. Trends in the 25th percentile of mean annual streamflow have declined and the center of timing has occurred earlier. We quantify the relative influences of total precipitation and air temperature on the annual low streamflow extremes from 42 stream gauges using mean annual streamflow as a proxy for precipitation amount effects and streamflow center of timing as a proxy for temperature effects on low flow metrics, including 7q10 summer (the minimum 7 day flow during summer with a 10 year return period), mean August, mean September, mean summer, 7q10 winter, and mean winter flow metrics. These methods have the benefit of using only readily available streamflow data, which makes our results robust against systematic errors in high elevation distributed precipitation data. Winter low flow metrics are weakly tied to both mean annual streamflow and center of timing.

  19. Time series decomposition of remotely sensed land surface temperature and investigation of trends and seasonal variations in surface urban heat islands

    Science.gov (United States)

    Quan, Jinling; Zhan, Wenfeng; Chen, Yunhao; Wang, Mengjie; Wang, Jinfei

    2016-03-01

    Previous time series methods have difficulties in simultaneous characterization of seasonal, gradual, and abrupt changes of remotely sensed land surface temperature (LST). This study proposed a model to decompose LST time series into trend, seasonal, and noise components. The trend component indicates long-term climate change and land development and is described as a piecewise linear function with iterative breakpoint detection. The seasonal component illustrates annual insolation variations and is modeled as a sinusoidal function on the detrended data. This model is able to separate the seasonal variation in LST from the long-term (including gradual and abrupt) change. Model application to nighttime Moderate Resolution Imaging Spectroradiometer (MODIS)/LST time series during 2000-2012 over Beijing yielded an overall root-mean-square error of 1.62 K between the combination of the decomposed trend and seasonal components and the actual MODIS/LSTs. LST decreased (~ -0.086 K/yr, p sixth ring roads. The decreasing trend was stronger over croplands than over urban lands (p < 0.05), resulting in an increasing trend in surface urban heat island intensity (SUHII, 0.022 ± 0.006 K/yr). This was mainly attributed to the trends in urban-rural differences in rainfall and albedo. The SUHII demonstrated a concave seasonal variation primarily due to the seasonal variations of urban-rural differences in temperature cooling rate (related to canyon structure, vegetation, and soil moisture) and surface heat dissipation (affected by humidity and wind).

  20. Marine-Based Nutraceuticals: An Innovative Trend in the Food and Supplement Industries.

    Science.gov (United States)

    Suleria, Hafiz Ansar Rasul; Osborne, Simone; Masci, Paul; Gobe, Glenda

    2015-10-01

    Recent trends in functional foods and supplements have demonstrated that bioactive molecules play a major therapeutic role in human disease. Nutritionists and biomedical and food scientists are working together to discover new bioactive molecules that have increased potency and therapeutic benefits. Marine life constitutes almost 80% of the world biota with thousands of bioactive compounds and secondary metabolites derived from marine invertebrates such as tunicates, sponges, molluscs, bryozoans, sea slugs and many other marine organisms. These bioactive molecules and secondary metabolites possess antibiotic, antiparasitic, antiviral, anti-inflammatory, antifibrotic and anticancer activities. They are also inhibitors or activators of critical enzymes and transcription factors, competitors of transporters and sequestrants that modulate various physiological pathways. The current review summaries the widely available marine-based nutraceuticals and recent research carried out for the purposes of isolation, identification and characterization of marine-derived bioactive compounds with various therapeutic potentials. PMID:26473889

  1. Research Trends of Soft Actuators based on Electroactive Polymers and Conducting Polymers

    Science.gov (United States)

    Kaneto, K.

    2016-04-01

    Artificial muscles (or soft actuators) based on electroactive polymers (EAPs) are attractive power sources to drive human-like robots in place of electrical motor, because they are quiet, powerful, light weight and compact. Among EAPs for soft actuators, conducting polymers are superior in strain, stress, deformation form and driving voltage compared with the other EAPs. In this paper, the research trends of EAPs and conducting polymers are reviewed by retrieval of the papers and patents. The research activity of EAP actuators showed the maximum around 2010 and somehow declining now days. The reasons for the reducing activity are found to be partly due to problems of conducting polymer actuators for the practical application. The unique characteristics of conducting polymer actuators are mentioned in terms of the basic mechanisms of actuation, creeping, training effect and shape retention under high tensile loads. The issues and limitation of conducting polymer soft actuators are discussed.

  2. Trend analysis of public opinion based on Markov chain%基于马尔可夫链的舆情热度趋势分析

    Institute of Scientific and Technical Information of China (English)

    刘勘; 李晶; 刘萍

    2011-01-01

    Public opinion often has a hidden trend behind its characteristics shown online.A Markov chain based public opin ion analysis method is proposed.In this method, indicator data of public opinion are collected to get the value of time series for the trend.Then the trend changes and the state spaces are analyzed, and the state transition matrix for the final trend is built.Experiments demonstrate that this method can effectively predict the trend of focus public opinion, and be of signifi cance in guiding and controlling the public opinion.%针对舆情热度的波动范围较大,并会呈现某种趋势的特点,提出了一种基于马尔可夫链的舆情热度趋势分析模型.该模型采集相关热点舆情的指标数据,得到热度的时间序列值;分析热度的趋势变化,划分状态空间,构建状态转移矩阵,预测热度的趋势变化区间.实验表明,该方法能有效地预测热点舆情的走势,进而辅助对舆情的引导和控制.

  3. Reversal of English trend towards hospital death in dementia: a population-based study of place of death and associated individual and regional factors, 2001–2010

    OpenAIRE

    Sleeman, Katherine E; Ho, Yuen K.; Verne, Julia; Gao, Wei; Higginson, Irene J.

    2014-01-01

    Background England has one of the highest rates of hospital death in dementia in Europe. How this has changed over time is unknown. This study aimed to analyse temporal trends in place of death in dementia over a recent ten year period. Methods Population-based study linking Office for National Statistics mortality data with regional variables, in England 2001–2010. Participants were adults aged over 60 with a death certificate mention of dementia. Multivariable Poisson regression was used to...

  4. Time resolved excitation dynamics in emeraldine base

    Energy Technology Data Exchange (ETDEWEB)

    Menšík, Miroslav, E-mail: mensik@imc.cas.cz; Rais, David; Pfleger, Jiří

    2015-07-29

    Highlights: • fs-transient absorption spectra of emeraldine base of polyaniline pumped at 700 nm. • Kinetic master equations for experimental data. • Formation of charge transfer states within 50 fs. Non-radiative decay (0.5 ps). • Phenyl rings relaxation (2.1 ps). • Formation of long-lived polarons (∼ns). - Abstract: Using femtosecond pump–probe transient absorption spectroscopy (wavelengths 330–800 nm), we observed and explained excited state, charge transfer and polaron state dynamics in emeraldine base form of polyaniline in dimethyl sulfoxide solution. The excited state created by a pump pulse (700 nm) in the quinoid absorption Q-band loses its initial symmetry by subsequent energy transition to a charge transfer state within 50 fs. The hot charge transfer state either recombines non-radiatively into the ground state with decay time constant 0.55 ps or transfers into a relaxed state corresponding to the relaxed phenyl geometry during ca 2.1 ps. This relaxed state shows a prolonged lifetime of about 6.5 ps before its recombination to the ground state. However, a small amount of long-lived polarons with lifetime of about 2 ns in air and with lifetime longer than 6 ns in the solution bubbled with dry N{sub 2} was detected.

  5. Application of uncertainty reasoning based on cloud model in time series prediction

    Institute of Scientific and Technical Information of China (English)

    张锦春; 胡谷雨

    2003-01-01

    Time series prediction has been successfully used in several application areas, such as meteoro-logical forecasting, market prediction, network traffic forecasting, etc. , and a number of techniques have been developed for modeling and predicting time series. In the traditional exponential smoothing method, a fixed weight is assigned to data history, and the trend changes of time series are ignored. In this paper, an uncertainty reasoning method, based on cloud model, is employed in time series prediction, which uses cloud logic controller to adjust the smoothing coefficient of the simple exponential smoothing method dynamically to fit the current trend of the time series. The validity of this solution was proved by experiments on various data sets.

  6. Application of uncertainty reasoning based on cloud model in time series prediction

    Institute of Scientific and Technical Information of China (English)

    张锦春; 胡谷雨

    2003-01-01

    Time series prediction has been successfully used in several application areas, such as meteorological forecasting, market prediction, network traffic forecasting, etc., and a number of techniques have been developed for modeling and predicting time series. In the traditional exponential smoothing method, a fixed weight is assigned to data history, and the trend changes of time series are ignored. In this paper, an uncertainty reasoning method, based on cloud model, is employed in time series prediction, which uses cloud logic controller to adjust the smoothing coefficient of the simple exponential smoothing method dynamically to fit the current trend of the time series. The validity of this solution was proved by experiments on various data sets.

  7. Dental anxiety and dental attendance among 25-year-olds in Norway: time trends from 1997 to 2007

    Directory of Open Access Journals (Sweden)

    Skaret Erik

    2011-03-01

    Full Text Available Abstract Background So far, there are few studies considering the development of dental anxiety and dental attendance patterns across time in the general population of Norwegian adults. This study aimed to 1 determine the frequency of dental anxiety and regular dental attendance among 25-year-olds in Norway in 1997 and 2007, 2 to study the development (time trend of dental anxiety and the socio-behavioral distribution of dental anxiety from 1997 to 2007. Method Random samples of 1,190 and 8,000 25-yr-olds were drawn from the populations of three counties in Western Norway in 1997 and 2007, respectively. The eligible participants received questionnaires by mail including questions on socio-demographics, dental anxiety (DAS and dental attendance. Results In 1997, 11.5% males versus 23% females reported high dental anxiety (DAS ≥ 13. Corresponding figures in 2007 were 11.3% and 19.8%. The proportions who had attended yearly for a dental check-up during the past 5 years fell from 62% in 1997 (men 56.9% and women 66.4% to 44.6% (men 38.1% and women 48.6% in 2007. After controlling for potential confounding factors, the 25-year-olds were 1.4 times more likely to report dental anxiety in 1997 compared to 2007. The decrease was largely attributable to a lower mean DAS score among higher educated females in 2007 than in 1997. The discrepancy in dental anxiety between regular and non-regular dental attendees had decreased, largely attributable to a decline in dental anxiety among irregular dental attendees. Conclusion The study showed reduced dental anxiety and dental attendance among 25 year-olds in Norway from 1997 to 2007. This study points to the importance of controlling for possible changes in socio-demographic distributions when different cohorts are compared.

  8. Life time risk for development of ten major cancers in India and its trends over the years 1982 to 2000

    Directory of Open Access Journals (Sweden)

    Satyanarayana L

    2008-02-01

    Full Text Available Background : Understanding cancer magnitude, risk and trends will be of help in cancer control programs. Aim : To study trends in cumulative risk up to 64 years of age as lifetime risk of developing major cancers in India during the years 1982 to 2000. Design : Retrospective. Setting : Secondary sources of cancer-registration data. Materials and Methods : Data on age-specific cancer-incidence rates were collected for patients 0-64 years of age of either sex for 10 major cancer sites from the National Cancer Registry Program (NCRP reports of India from Mumbai, Chennai, Bangalore, Bhopal and Delhi; and Barshi registries for the years 1982 or 1988 to 2000. Statistical Analysis : Cumulative risks computed for lifetime development of cancer. Linear trends were studied using simple linear regressions. Results : The lifetime risk among females for the10 cancer sites ranged from 0.02 to 3.3% and from 0.04 to 2.4% for the years 1982 and 2000 respectively; whereas among males, it ranged from 0.04 to 0.89% and from 0.05 to 0.95% respectively. Significant (P < 0.05 increasing trends were observed for breast, non-Hodgkin′s lymphoma (NHL, gallbladder, thyroid and ovary cancers among females; while declining trends were observed for cervix, mouth, stomach, esophagus and tongue cancers. Among males, significant (P < 0.05 increasing trends were observed for NHL and prostate cancer; whereas declining trends were observed for stomach, liver, hypopharynx and tongue cancers. Cancers of mouth and esophagus showed increasing trends (P < 0.05 in some regions and declining trends (P < 0.05 in some other. Conclusion : Significant and higher rates of positive trends in lifetime cancer risks for breast cancer among females and for NHL among both sexes were observed.

  9. Chaos Time Series Prediction Based on Membrane Optimization Algorithms

    Directory of Open Access Journals (Sweden)

    Meng Li

    2015-01-01

    Full Text Available This paper puts forward a prediction model based on membrane computing optimization algorithm for chaos time series; the model optimizes simultaneously the parameters of phase space reconstruction (τ,m and least squares support vector machine (LS-SVM (γ,σ by using membrane computing optimization algorithm. It is an important basis for spectrum management to predict accurately the change trend of parameters in the electromagnetic environment, which can help decision makers to adopt an optimal action. Then, the model presented in this paper is used to forecast band occupancy rate of frequency modulation (FM broadcasting band and interphone band. To show the applicability and superiority of the proposed model, this paper will compare the forecast model presented in it with conventional similar models. The experimental results show that whether single-step prediction or multistep prediction, the proposed model performs best based on three error measures, namely, normalized mean square error (NMSE, root mean square error (RMSE, and mean absolute percentage error (MAPE.

  10. A Global Process-Based Study of Marine CCN Trends and Variability

    Science.gov (United States)

    Dunne, E. M.; Mikkonen, S.; Kokkola, H.; Korhonen, H.

    2014-12-01

    One proposed climate feedback mechanism is that, in a warming climate, wind speeds might change, altering emission rates of natural marine aerosols. This would affect the albedo of marine clouds, which have a strong cooling effect on a global scale. To investigate the sign and extent of this proposed feedback mechanism, we performed a fifteen-year simulation using the global aerosol microphysics model GLOMAP-mode. We then analysed wind speed values and CCN concentrations from GLOMAP using a dynamic linear model to find non-linear trends in the data. We compared trends in wind speed and CCN concentrations in three marine regions: the Northern Equatorial Pacific, the North Atlantic, and the Southern Ocean. No correlation was evident between wind speed and CCN concentrations in the NEP and the NA, indicating that a wind-based feedback is unlikely to have much effect in these regions. In the Southern Ocean, there is a stronger link between wind speed and CCN, suggesting a greater importance of natural, wind-driven aerosols. To determine which processes overwhelmed the influence of emissions to control CCN concentrations, we ran a set of six two-month simulations with high temporal resolution output: one control simulation, and five simulations with one aerosol microphysical process switched off (new particle formation, primary sea spray emissions, dimethyl sulphide emissions, nucleation scavenging, and impaction scavenging). We found that in-cloud scavenging determines the base level of CCN concentration, with a large contribution from new particle formation and marine emissions in two of the regions. However, we also found that day-to-day fluctuations in CCN concentrations were more closely linked to transport of continental emissions in the Northern Equatorial Pacific and the North Atlantic. Given the low sensitivity of CCN to changes in emissions, and the importance of transported continental aerosol, we expect that the proposed feedback mechanism is unlikely to

  11. Interpreting Space-Based Trends in Carbon Monoxide with Multiple Models

    Science.gov (United States)

    Strode, Sarah A.; Worden, Helen M.; Damon, Megan; Douglass, Anne R.; Duncan, Bryan N.; Emmons, Louisa K.; Lamarque, Jean-Francois; Manyin, Michael; Oman, Luke D.; Rodriguez, Jose M.; Strahan, Susan E.; Tilmes, Simone

    2016-01-01

    We use a series of chemical transport model and chemistry climate model simulations to investigate the observed negative trends in MOPITT CO over several regions of the world, and to examine the consistency of timedependent emission inventories with observations. We find that simulations driven by the MACCity inventory, used for the Chemistry Climate Modeling Initiative (CCMI), reproduce the negative trends in the CO column observed by MOPITT for 2000-2010 over the eastern United States and Europe. However, the simulations have positive trends over eastern China, in contrast to the negative trends observed by MOPITT. The model bias in CO, after applying MOPITT averaging kernels, contributes to the model-observation discrepancy in the trend over eastern China. This demonstrates that biases in a model's average concentrations can influence the interpretation of the temporal trend compared to satellite observations. The total ozone column plays a role in determining the simulated tropospheric CO trends. A large positive anomaly in the simulated total ozone column in 2010 leads to a negative anomaly in OH and hence a positive anomaly in CO, contributing to the positive trend in simulated CO. These results demonstrate that accurately simulating variability in the ozone column is important for simulating and interpreting trends in CO.

  12. Rising obesity-related hospital admissions among children and young people in England: national time trends study.

    Directory of Open Access Journals (Sweden)

    Jessica D Jones Nielsen

    Full Text Available To describe the trends in hospital admissions associated with obesity as a primary diagnosis and comorbidity, and bariatric surgery procedures among children and young people in England.National time trends study of hospital admissions data between 2000 and 2009.Children and young people aged 5 to 19 years who were admitted to hospital with any diagnosis of obesity.Age- and sex-specific admission rates per million children.Between 2000 and 2009, age- and sex-specific hospital admission rates in 5-19 year olds for total obesity-related diagnoses increased more than four-fold from 93.0 (95% CI 86.0 to 100.0 per million children to 414.0 (95% CI 410.7 to 417.5 per million children, largely due to rising admissions where obesity was mentioned as a co-morbidity. The median age of admission to hospital over the study period was 14.0 years; 5,566 (26.7% admissions were for obesity and 15,319 (73.3% mentioned obesity as a comorbidity. Admissions were more common in girls than boys (56.2% v 43.8%. The most common reasons for admission where obesity was a comorbid condition were sleep apnoea, asthma, and complications of pregnancy. The number of bariatric surgery procedures has risen from 1 per year in 2000 to 31 in 2009, with the majority were performed in obese girls (75.6% aged 13-19 years.Hospital admission rates for obesity and related comorbid conditions have increased more than four-fold over the past decade amongst children and young people. Although some of the increase is likely to be due to improved case ascertainment, conditions associated with obesity in children and young people are imposing greater challenges for health care providers in English hospitals. Most inpatient care is directed at dealing with associated conditions rather than primary assessment and management of obesity itself.

  13. Automatic trend estimation

    CERN Document Server

    Vamos¸, C˘alin

    2013-01-01

    Our book introduces a method to evaluate the accuracy of trend estimation algorithms under conditions similar to those encountered in real time series processing. This method is based on Monte Carlo experiments with artificial time series numerically generated by an original algorithm. The second part of the book contains several automatic algorithms for trend estimation and time series partitioning. The source codes of the computer programs implementing these original automatic algorithms are given in the appendix and will be freely available on the web. The book contains clear statement of the conditions and the approximations under which the algorithms work, as well as the proper interpretation of their results. We illustrate the functioning of the analyzed algorithms by processing time series from astrophysics, finance, biophysics, and paleoclimatology. The numerical experiment method extensively used in our book is already in common use in computational and statistical physics.

  14. Regression analyses of time trends of perinatal mortality and stillbirth proportions in Germany and Europe 1980-1993

    Energy Technology Data Exchange (ETDEWEB)

    Scherb, H.; Weigelt, E. [GSF-Forschungszentrum fuer Umwelt und Gesundheit, Inst. fuer Biomathematik und Biometrie, Oberschleissheim (Germany)

    2001-07-01

    In contrast to the western European trend, the eastern European trend exhibits an absolute increase of the stillbirth proportion in 1986 as compared with 1985 and an apparent upward shift of the whole trend line from 1986 on. The present result adds to the evidence of noticeable effects of the Chernobyl accident on public health such as the increases in the incidence of infant leukemia in Greece and Germany in 1986/1987 and an excess perinatal death proportion in Germany in 1987. (orig.)

  15. Socio-economic position and time trends in invasive management and case fatality after acute myocardial infarction in Denmark

    DEFF Research Database (Denmark)

    Mårtensson, Solvej; Gyrd-Hansen, Dorte; Prescott, Eva;

    2016-01-01

    BACKGROUND: Lower case fatality and increased use of evidence-based invasive management incl. coronary angiography (CAG) have been reported for patients admitted with acute myocardial infarction (AMI) in the last 25 years. This article seeks to investigate whether these advances have benefitted...... educational groups over time and the inequality in CAG within 1 and 3 days seen in the beginning of the time frame was eliminated. Case fatality decreased in all educational groups and the relative inequality in 30 days case fatality decreased for women but not 365 days case fatality. No change was seen...... for inequality in case fatality for men. CONCLUSION: Increased use of CAG within the evidence based time frame was observed along with a decrease in inequality. However, a reduction in inequality was only observed for short term case fatality, and only for women. These results suggest that inequality in case...

  16. Time trends in blood pressure, body mass index and smoking in the Vietnamese population: a meta-analysis from multiple cross-sectional surveys.

    Directory of Open Access Journals (Sweden)

    Quang Ngoc Nguyen

    Full Text Available INTRODUCTION: Data for trends in cardiovascular disease (CVD risk factors are needed to set priorities and evaluate intervention programmes in the community. We estimated time trends in blood pressure (BP, anthropometric variables and smoking in the Vietnamese population and highlighted the differences between men and women or between rural and urban areas. METHODS: A dataset of 23,563 adults aged 25-74 from 5 cross-sectional surveys undertaken within Vietnam from 2001 to 2009 by the Vietnam National Heart Institute was used to estimate mean BP, weight, waist circumference (WC, body mass index (BMI, the prevalence of hypertension, adiposity or smoking, which were standardised to the national age structure of 2009. Multilevel mixed linear models were used to estimate annual changes in the variables of interest, adjusted by age, sex, residential area, with random variations for age and surveyed provinces. FINDINGS: Among the adult population, the age-standardised mean systolic and diastolic BP increased by 0.8 and 0.3 mmHg in women, 1.1 and 0.4 mmHg in men, while the mean BMI increased by 0.1 kgm(-2 in women, 0.2 kgm(-2 in men per year. Consequently, the prevalence of hypertension and adiposity increased by 0.9 and 0.3% in women, 1.1 and 0.9% in men with similar time trends in both rural and urban areas, while smoking prevalence only increased in women by 0.3% per year. A U-shaped association was found between age-adjusted BP and BMI in both sexes and in both areas. CONCLUSIONS: From 2001 to 2009, mean BP, weight and WC significantly increased in the Vietnamese population, leading to an increased prevalence of hypertension and adiposity, suggesting the need for the development of multi-sectoral cost-effective population-based interventions to improve CVD management and prevention. The U-shaped relationship between BP and BMI highlighted the hypertension burden in the underweight population, which is usually neglected in CVD interventions.

  17. Interpretation of Research Evaluation Trends Based on REF%REF与科研评价趋向

    Institute of Scientific and Technical Information of China (English)

    宋丽萍

    2011-01-01

    通过分析英国高等教育评估体系从基于同行评议的RAE到基于文献计量的REF的变革,以REF为例探讨计量方法在科研评价中的应用,解读科学评价中两种主要方法之关系以及科研评价的趋向。指出:随着量化份额的增加,文献计量方法的正确应用将成为关键环节,以质量为导向的、同行评议与文献计量相结合的方法将成为未来科研评价的主流。%In the light of the change of UK higher education institutions from peer review based RAE to mainly metrics-based REF, and the application of bibliometrics to research assessment, the paper interpretates the trend of research evaluation and the relationship between the two main methods in it. It points out: with the increase of quantitative sharing, the correct application of bibliometric methods will be the key point, and quality-oriented, combining research assessment system between peer review and bibliometries will become the mainstream.

  18. Spatio-temporal trends in the hydroclimate of Turkey for the last decades based on two reanalysis datasets

    Science.gov (United States)

    Gokmen, Mustafa

    2016-09-01

    We present a regional assessment of the spatiotemporal trends in several hydro-climate variables from 1979 to 2010 in Turkey, one of the countries of the eastern Mediterranean vulnerable to climate change, using the two reanalysis products of the ECMWF: ERA-Interim and ERA-Interim/Land. The trend analysis revealed that an average warming of 1.26 °C [0.8-1.8] occurred in Turkey from 1979 to 2010, with high confidence intervals (95-99 %, mostly). Geographically, the largest warming (up to 1.8 °C) occurred in the western coastal areas next to the Aegean Sea and in the southeastern regions. The air temperature trends were generally confirmed by the in situ data from about 100 weather stations around the country, though in situ data indicated slightly higher trends ranging from 1 to 2.5°. With respect to the regional trends in hydrological variables, ERA-Interim and ERA-Interim/Land revealed quite different pictures: the ERA-Interim dataset indicated that there have been significant decreasing trends of precipitation, snow water equivalent (SWE) and runoff in some parts of inner/southeastern Anatolia (a total decrease of up to 250 mm in the upstream of the Euphrates, Kizilirmak and Seyhan basins), while ERA-Interim/Land showed no or minor trends in the same areas. Based on the extensive comparisons with precipitation and SWE gauge data, we can suggest that the hydrological trends shown by the ERA-Interim/Land dataset, which is said to be a model improvement, are relatively closer to the observations. From the hydrological trends revealed by the ERA-Interim/Land dataset, we can conclude that, despite the strong warming trends over Turkey from 1979 to 2010, there have been no widespread and strong hydrological trends for the same period throughout the country. In this regard, we can suggest that the impacts of global warming on the water cycle are not straightforward, especially at the regional scale, and future climate simulations indicating considerable

  19. NEW TRENDS IN MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Micu Alexandra

    2014-07-01

    Full Text Available Over the last years, management have been facing a series of profound changes in trends coming and going, one being more productive than other or causing more damage when applied improperly. The paper focuses on the last trends in management that have evolved in the last years, trends that have been marked by a Darwinian business environment and made more unforgiving since the financial crisis and the innovations in technology, social media and management philosophy. The paper will present and describe the most important new trends in management that enabled select organisations to remain competitive and overcome the multiple difficulties caused by the ever-changing economy based on a qualitative research. From the “outside innovation” that is considered always to be the key in overcoming the obstacles facing an organization, to the new buzzword “design”, that is said to ensure the organization long-term competitive advantage, the paper will analyse new trends and also will be describing the impact they have on the welfare of the organization. The research has also shown that managers tend to put a greater accent on searching for innovation rather than efficiency in order to ensure a continuous progress in the organization and to maintain business sustainability. The paper will not be comparing the efficiency of these different philosophies, or the results they generated, as time will still be the ultimate judge.

  20. A New-Trend Model-Based to Solve the Peak Power Problems in OFDM Systems

    Directory of Open Access Journals (Sweden)

    Ashraf A. Eltholth

    2008-01-01

    Full Text Available The high peak to average power ration (PAR levels of orthogonal frequency division multiplexing (OFDM signals attract the attention of many researchers during the past decade. Existing approaches that attack this PAR issue are abundant, but no systematic framework or comparison between them exists to date. They sometimes even differ in the problem definition itself and consequently in the basic approach to follow. In this paper, we propose a new trend in mitigating the peak power problem in OFDM system based on modeling the effects of clipping and amplifier nonlinearities in an OFDM system. We showed that the distortion due to these effects is highly related to the dynamic range itself rather than the clipping level or the saturation level of the nonlinear amplifier, and thus we propose two criteria to reduce the dynamic range of the OFDM, namely, the use of MSK modulation and the use of Hadamard transform. Computer simulations of the OFDM system using Matlab are completely matched with the deduced model in terms of OFDM signal quality metrics such as BER, ACPR, and EVM. Also simulation results show that even the reduction of PAR using the two proposed criteria is not significat, and the reduction in the amount of distortion due to HPA is truley delightful.

  1. Performance Analysis Based on Timing Simulation

    DEFF Research Database (Denmark)

    Nielsen, Christian Dalsgaard; Kishinevsky, Michael

    1994-01-01

    Determining the cycle time and a critical cycle is a fundamental problem in the analysis of concurrent systems. We solve this problemusing timing simulation of an underlying Signal Graph (an extension of Marked Graphs). For a Signal Graph with n vertices and m arcs our algorithm has the polynomia...... time complexity O(b2m), where b is the number of vertices with initially marked in-arcs (typically b≪n). The algorithm has a clear semantic and a low descriptive complexity. We illustrate the use of the algorithm by applying it to performance analysis of asynchronous circuits.......Determining the cycle time and a critical cycle is a fundamental problem in the analysis of concurrent systems. We solve this problemusing timing simulation of an underlying Signal Graph (an extension of Marked Graphs). For a Signal Graph with n vertices and m arcs our algorithm has the polynomial...

  2. Criteria Air Emissions Trends

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Air Emissions Trends site provides national trends of criteria pollutant and precursor emissions data based on the the National Emissions Inventory (NEI) from...

  3. Time-trends in the utilization of decentralized mental health services in Norway - A natural experiment: The VELO-project

    Directory of Open Access Journals (Sweden)

    Bjorbekkmo Svein

    2010-03-01

    Full Text Available Abstract Background There are few reports on the effects of extensive decentralization of mental health services. We investigated the total patterns of utilization in a local-bed model and a central-bed model. Methods In a time-trend case-registry design, 7635 single treatment episodes, from the specialist and municipality services in 2003-2006, were linked to 2975 individual patients over all administrative levels. Patterns of utilization were analyzed by univariate comparisons and multivariate regressions. Results Total treated prevalence was consistently higher for the central-bed system. Outpatient utilization increased markedly, in the central-bed system. Utilization of psychiatric beds decreased, only in the central-bed system. Utilization of highly supported municipality units increased in both systems. Total utilization of all types of services, showed an additive pattern in the local-bed system and a substitutional pattern in the central-bed system. Only severe diagnoses predicted inpatient admission in the central-bed system, whereas also anxiety-disorders and outpatient consultations predicted inpatient admission in the local-bed system. Characteristics of the inpatient populations changed markedly over time, in the local-bed system. Conclusions Geographical availability is not important as a filter in patients' pathway to inpatient care, and the association between distance to hospital and utilization of psychiatric beds may be an historical artefact. Under a public health-insurance system, local psychiatric personnel as gatekeepers for inpatient care may be of greater importance than the availability of local psychiatric beds. Specialist psychiatric beds and highly supported municipality units for people with mental health problems do not work together in terms of utilization. Outpatient and day-hospital services may be filters in the pathway to inpatient care, however this depends on the structure of the whole service-system. Local

  4. The Trend of Body Donation for Education Based on Korean Social and Religious Culture

    Science.gov (United States)

    Park, Jong-Tae; Jang, Yoonsun; Park, Min Sun; Pae, Calvin; Park, Jinyi; Hu, Kyung-Seok; Park, Jin-Seo; Han, Seung-Ho; Koh, Ki-Seok; Kim, Hee-Jin

    2011-01-01

    Until a century ago, Korean medicine was based mainly on Oriental philosophies and ideas. From a religious perspective, Chinese Confucianism was prevalent in Korea at that time. Since Confucianists believe that it is against one's filial duty to harm his or her body, given to them by their parents, most Koreans did not donate their bodies or…

  5. 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.

  6. Ozone tropospheric and stratospheric trends (1995-2008) over Western Europe from ground-based FTIR network observations

    Science.gov (United States)

    Vigouroux, Corinne; Demoulin, Philippe; Blumenstock, Thomas; Schneider, Matthias; Klyft, Jon; Palm, Mathias; Gardiner, Tom

    2010-05-01

    Five ground-based stations in Western Europe, from 79°N to 28°N, all part of the Network for the Detection of Atmospheric Composition Change (NDACC), have joined their efforts to homogenize and optimize the retrievals of ozone profiles from FTIR (Fourier transform infrared) solar absorption spectra. Using the optimal estimation method, distinct vertical information can be obtained in four layers: ground--10 km, 10--18 km, 18--27 km, and 27--42 km, in addition to total column amounts. A bootstrap resampling method has been implemented to determine annual partial and total column trends1. Vigouroux et al. (2008)2 applied this method to the ozone data and discussed the trends of the total columns and of the partial columns in the above four layers, over the period 1995-2004. Here, we present and discuss an update of this analysis for the 1995-2008 period. We obtain, among others, that at all the stations, the ozone total columns trends are non significant while the trends in the upper stratospheric layer (27-42 km) are significantly positive. 1 Gardiner, T., Forbes, A., Woods, P., De Mazière, M., Vigouroux, C., Mahieu, E., Demoulin, P., Velazco, V., Notholt, J., Blumenstock, T., Hase, F., Kramer, I., Sussmann, R., Stremme, W., Mellqvist, J., Strandberg, A., Ellingsen, K., and Gauss, M.: Method for evaluating trends in greenhouse gases from ground-based remote FTIR measurements over Europe, ACP, 8, 6719-6727, 2008. 2 Vigouroux, C., De Mazière, M., Demoulin, P., Servais, C., Hase, F., Blumenstock, T., Kramer, I., Schneider, M., Mellqvist, J., Strandberg, A., Velazco, V., Notholt, J., Sussmann, R., Stremme, W., Rockmann, A., Gardiner, T., Coleman, M., and Woods, P. : Evaluation of tropospheric and stratospheric ozone trends over Western Europe from ground-based FTIR network observations, ACP, 8, 6865-6886, 2008.

  7. 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.

  8. Time-trends and circumstances surrounding ankle injuries in men's professional football : an 11-year follow-up of the UEFA Champions League injury study

    OpenAIRE

    Waldén, Markus; Hägglund, Martin; Ekstrand, Jan

    2013-01-01

    Background Ankle injury is common in football, but the circumstances surrounding them are not well characterised. Aim To investigate the rates, especially time-trends, and circumstances of ankle injuries in male professional football. Methods 27 European clubs with 1743 players were followed prospectively between 2001/2002 and 2011/2012. Time loss injuries and individual-player exposure during training sessions and matches were recorded. Injury rate was defined as the number of injuries/1000 ...

  9. Long-term Measurements of Summer-time Ozone at the Walnut Grove Tower - Understanding Trends in the Boundary Layer

    Science.gov (United States)

    Mahmud, A.; Di, P.; Mims, D.; Avise, J.; DaMassa, J.; Kaduwela, A. P.

    2015-12-01

    The California Air Resources Board (CARB) has been monitoring boundary layer ozone at the Walnut Grove Tower (WGT) since 1996 for investigating regional transport and vertical profile. Walnut Grove is located between Sacramento and Stockton, CA in the Sacramento - San Joaquin Delta. Sampling inlets are positioned at 30-ft, 400-ft, 800-ft, 1200-ft and 1600-ft levels of the 2000-ft tower, which is one of the tallest monitoring towers in the Western US. Ozone, ambient temperature, wind speed, and wind direction are simultaneously measured at each level, and reported as hourly averages. The current study included analyses of available ozone and corresponding meteorological data for the months of June - September from 1996 - 2014 with objectives to: 1) explore trends and inter-annual variability of ozone, 2) examine any correlations between ozone and meteorological parameters, 3) understand interactions of ozone measured at various levels, and 4) assess how well a regulatory state-of-the-science air quality model such as the Community Multi-scale Air Quality Model (CMAQ) captures observation. Daily 1-hr maximum ozone has been consistently decreasing during the 1996 - 2014 period at a rate of ~1 ppb per year. This indicates that CARB's measures to control ambient ozone have been effective over the past years. Evolution of the vertical profile throughout the day shows that ozone is fairly homogeneously mixed between 1 - 5 pm, when mixing height typically reaches the maximum. Ozone at 30-ft shows the greatest variability because of its proximity to the ground and emissions sources - rises faster during morning hours (7 - 10 am) and declines more rapidly during evening hours (7 - 10 pm) compared to other levels. Air masses reaching the tower are predominantly southwesterly (247 - 257 deg.) at the bottom, and southwesterly to slightly northwesterly (254 - 302 deg.) at top levels. Daily 1-hr maximum ozone was negatively correlated with wind speed (i.e. ozone was high under

  10. Prevalence and time trends in diabetes and physical inactivity among adult West African populations: The epidemic has arrived

    NARCIS (Netherlands)

    A.R. Abubakari; W. Lauder; M.C. Jones; A. Kirk; C. Agyemang; R.S. Bhopal

    2009-01-01

    Objective: To determine the prevalence and distribution of, and trends in, physical inactivity and diabetes in adult West African populations. Design: Systematic review and meta-analysis. Methods: Literature searches were conducted using four electronic databases. journal hand searches and examinati

  11. Document stream clustering: experimenting an incremental algorithm and AR-based tools for highlighting dynamic trends

    CERN Document Server

    Lelu, Alain; Cuxac, Pascal

    2008-01-01

    We address here two major challenges presented by dynamic data mining: 1) the stability challenge: we have implemented a rigorous incremental density-based clustering algorithm, independent from any initial conditions and ordering of the data-vectors stream, 2) the cognitive challenge: we have implemented a stringent selection process of association rules between clusters at time t-1 and time t for directly generating the main conclusions about the dynamics of a data-stream. We illustrate these points with an application to a two years and 2600 documents scientific information database.

  12. Japanese secular trends in birthweight and the prevalence of low birthweight infants during the last three decades: A population-based study.

    Science.gov (United States)

    Takemoto, Yo; Ota, Erika; Yoneoka, Daisuke; Mori, Rintaro; Takeda, Satoru

    2016-01-01

    Since low birthweight has been correlated with both neonatal and long-term health, we performed this epidemiological study to evaluate the Japanese secular trends in mean birthweight and the prevalence of preterm/term low birthweight infants during the last three decades. We used population-based birth certificate data from January 1979 to December 2010. Time trends were analysed using a linear regression model. During the study period, we observed a significant decrease in the mean birthweight for singleton live births (3,152 ± 436 g in 1979 and 3,018 ± 421 g in 2010 p us to identify the associated risk factors and reduce the future socioeconomic burden that is associated with low birthweight infants. PMID:27503177

  13. The nutritional status of children in Bhutan: results from the 2008 National nutrition survey and trends over time

    Directory of Open Access Journals (Sweden)

    Zangmo Ugyen

    2012-09-01

    Full Text Available Abstract Background There are few reports on the nutritional status of Bhutanese children. The objective of this paper is to summarize results from the 2008 National Nutrition Survey and to describe progress achieved during the last two decades. Methods A cross-sectional survey of 2376 children aged 6 to 59 months was conducted during November-December 2008 to provide national and regional estimates. A multi-stage cluster sampling method was applied and 40 gewogs/thromdes were selected from each region (Western, Central, Eastern. Guidelines on how to measure length/height and weight followed WHO standardized procedures. Data were analysed for consistency and validation using the software WHO Anthro and the WHO SPSS macro. Underweight, stunting, overweight, wasting and thinness were defined based on the WHO Child Growth Standards. Data from 1986-88 and 1999 national surveys were reanalysed using the WHO standards to describe trends in nutritional status. Results Nationally, 34.9% Bhutanese preschool children are stunted and 10.4% are underweight. Wasting is 4.7%, with severe wasting close to 2% in rural areas, while overweight affects 4.4% of preschool children. While underweight rates are similar across regions, wasting is substantially more prevalent in the Western region and stunting in the Eastern region. Stunting shows a steep rise during the first two years of life, as high as 40%, and levels off thereafter, while wasting is greatest among children aged 6-24 months and subsequently decreases. The prevalence of stunting fell from 60.9% in 1986-88 to 34.9% in 2008, and underweight declined from 34.0% to 10.4% during same period. The percentage of wasted children dropped from 5.2% in 1986-88 to 2.5% in 1999 but then increased to 4.7% in 2008. Conclusions There have been major improvements in the nutritional status of Bhutanese children over the past two decades, however, linear growth retardation remains a significant concern. Early

  14. Trends in the Rare Earth Element Content of U.S.-Based Coal Combustion Fly Ashes.

    Science.gov (United States)

    Taggart, Ross K; Hower, James C; Dwyer, Gary S; Hsu-Kim, Heileen

    2016-06-01

    Rare earth elements (REEs) are critical and strategic materials in the defense, energy, electronics, and automotive industries. The reclamation of REEs from coal combustion fly ash has been proposed as a way to supplement REE mining. However, the typical REE contents in coal fly ash, particularly in the United States, have not been comprehensively documented or compared among the major types of coal feedstocks that determine fly ash composition. The objective of this study was to characterize a broad selection of U.S. fly ashes of varied geological origin in order to rank their potential for REE recovery. The total and nitric acid-extractable REE content for more than 100 ash samples were correlated with characteristics such as the major element content and coal basin to elucidate trends in REE enrichment. Average total REE content (defined as the sum of the lanthanides, yttrium, and scandium) for ashes derived from Appalachian sources was 591 mg kg(-1) and significantly greater than in ashes from Illinois and Powder River basin coals (403 and 337 mg kg(-1), respectively). The fraction of critical REEs (Nd, Eu, Tb, Dy, Y, and Er) in the fly ashes was 34-38% of the total and considerably higher than in conventional ores (typically less than 15%). Powder River Basin ashes had the highest extractable REE content, with 70% of the total REE recovered by heated nitric acid digestion. This is likely due to the higher calcium content of Powder River Basin ashes, which enhances their solubility in nitric acid. Sc, Nd, and Dy were the major contributors to the total REE value in fly ash, based on their contents and recent market prices. Overall, this study shows that coal fly ash production could provide a substantial domestic supply of REEs, but the feasibility of recovery depends on the development of extraction technologies that could be tailored to the major mineral content and origins of the feed coal for the ash. PMID:27228215

  15. Exploring Spatiotemporal Trends in Commercial Fishing Effort of an Abalone Fishing Zone: A GIS-Based Hotspot Model.

    Directory of Open Access Journals (Sweden)

    M Ali Jalali

    Full Text Available Assessing patterns of fisheries activity at a scale related to resource exploitation has received particular attention in recent times. However, acquiring data about the distribution and spatiotemporal allocation of catch and fishing effort in small scale benthic fisheries remains challenging. Here, we used GIS-based spatio-statistical models to investigate the footprint of commercial diving events on blacklip abalone (Haliotis rubra stocks along the south-west coast of Victoria, Australia from 2008 to 2011. Using abalone catch data matched with GPS location we found catch per unit of fishing effort (CPUE was not uniformly spatially and temporally distributed across the study area. Spatial autocorrelation and hotspot analysis revealed significant spatiotemporal clusters of CPUE (with distance thresholds of 100's of meters among years, indicating the presence of CPUE hotspots focused on specific reefs. Cumulative hotspot maps indicated that certain reef complexes were consistently targeted across years but with varying intensity, however often a relatively small proportion of the full reef extent was targeted. Integrating CPUE with remotely-sensed light detection and ranging (LiDAR derived bathymetry data using generalized additive mixed model corroborated that fishing pressure primarily coincided with shallow, rugose and complex components of reef structures. This study demonstrates that a geospatial approach is efficient in detecting patterns and trends in commercial fishing effort and its association with seafloor characteristics.

  16. Population based trends in mortality, morbidity and treatment for very preterm- and very low birth weight infants over 12 years

    Directory of Open Access Journals (Sweden)

    Rüegger Christoph

    2012-02-01

    Full Text Available Abstract Background Over the last two decades, improvements in medical care have been associated with a significant increase and better outcome of very preterm (VP, Methods Our population-based observational cohort study used the Minimal Neonatal Data Set, a database maintained by the Swiss Society of Neonatology including information of all VP- and VLBW infants. Perinatal characteristics, mortality and morbidity rates and the survival free of major complications were analysed and their temporal trends evaluated. Results In 1996, 2000, 2004, and 2008, a total number of 3090 infants were enrolled in the Network Database. At the same time the rate of VP- and VLBW neonates increased significantly from 0.87% in 1996 to 1.10% in 2008 (p Conclusions Over the 12-year observation period, the number of VP- and VLBW infants increased significantly. An unchanged overall mortality rate and an increase of survivors free of major complication resulted in a considerable net gain in infants with potentially good outcome.

  17. Tendências temporais de atividade física no Brasil (2006-2009 Time trends of physical activity in Brazil (2006-2009

    Directory of Open Access Journals (Sweden)

    Pedro C Hallal

    2011-09-01

    Full Text Available OBJETIVO: Analisar as tendências temporais de atividade física (AF nas capitais brasileiras entre 2006 e 2009. MÉTODOS: A análise apresentada neste artigo é baseada nos dados do VIGITEL, totalizando uma amostra anual aproximada de 54.000 indivíduos. Foram analisados indicadores de AF no tempo livre, trabalho, em casa e no deslocamento, além do tempo assistindo à televisão e de inatividade considerando todos os domínios de AF. A variação dos indicadores no período foi aferida por meio de modelos de regressão de Poisson, tendo como variável explanatória o ano do inquérito. Foi considerada significativa a evolução correspondente a um coeficiente de regressão diferente de zero (pOBJECTIVE: To examine time trends in physical activity (PA in Brazilian state capitals from 2006 to 2009. METHODS: This analysis is based on data from the Telephone-based Surveillance of Risk and Protective Factors for Chronic Diseases (VIGITEL accounting for an annual sample of approximately 54,000 individuals. PA indicators were analyzed in free time (leisure, work, home and transportation, time spent in front of the television and inactivity considering all PA domains. Poisson regression models were used to measure the variation of indicators over time. We considered the changes corresponding to a regression coefficient different from zero as being statistically significant (p<0.05. RESULTS: The percentage of active commuters increased from 11.7 to 14.4% (p<0.001 whereas the proportion of physically inactive individuals in the four domains decreased from 11.7 to 8.7% (p<0.001. There were no significant changes in the other indicators. Women were less active than men in all indicators, except for household chores. However, in this indicator the percentage of active women decreased from 71.4 to 67.1% (p<0.001. Between 2006 and 2009, PA levels in the Brazilian population were stable during free time and household chores, but increased in transportation

  18. Sediment transport modelling based on grain size trend analysis in Augusta Harbour (Sicily)

    Science.gov (United States)

    Barbera, Giuseppe; Feo, Roberto; Freni, Gabriele

    2015-12-01

    To support marine civil engineer in pollutant studies, sediment management or dredging operations, is useful to know how the sediments move in accumulation basin. This paper investigates the dynamic of the sediment path using a two-dimensional numeric model: the Grain Size Trend Analysis (GSTA). The GSTA was applied using GiSedTrend plugin, under GIS software. The case study is the Augusta Harbour, which is one of the most polluted Italian harbours. It is the marine part of the Site of National Interest (SNI) of Priolo Gargallo (Siracusa, Italy) and it can be hydrodynamically considered as a lagoon. Two scenarios were obtained by using different geostatistical criteria.

  19. Bias of genetic trend of genomic predictions based on both real dairy cattle and simulated data

    DEFF Research Database (Denmark)

    Ma, Peipei; Lund, Mogens Sandø; Nielsen, Ulrik Sander;

    population. In simulated data, there was no bias when the test animals were unselected cows. When the G matrix was derived from genotypes of causal genes, the bias was reduced. The results suggest that the main reasons for causing the bias of the prediction trends are the selection of bulls and bull dams......This study investigated the phenomenon of bias in the trend of genomic predictions and attempted to find the reason and solution for this bias. The data used in this study include Danish Jersey data and simulation data. In Jersey data, the bias was reduced when cows were included in the reference...

  20. Time trends in cardiovascular disease mortality in Russia and Germany from 1980 to 2007 - are there migration effects?

    Directory of Open Access Journals (Sweden)

    Deckert Andreas

    2010-08-01

    Full Text Available Abstract Background Cardiovascular disease (CVD is the leading cause of death in the industrialized world. Large variations in CVD mortality between countries and also between population subgroups within countries have been observed. Previous studies showed significantly lower risks in German repatriates and Jews emigrating from Russia than in the general Russian population. We examined to what degree the migration of large subgroups influenced national CVD mortality rates. Methods We used WHO data to map the CVD mortality distribution in Europe in 2005. Supplemented by data of the Statistisches Bundesamt, the mortality trends in three major CVD groups between 1980 and 2007 in Russia and Germany are displayed, as well as demographic information. The effects of migration on demography were estimated and percentage changes in CVD mortality trends were calculated under the assumption that migration had not occurred. Results Cardiovascular disease mortality patterns within Europe showed a strong west-east gradient with ratios up to sixfold. In Germany, the CVD mortality levels were low and steadily decreasing, whereas in Russia they fluctuated at high levels with substantial differences between the sexes and strong correlations with political changes and health campaigns. The trends in both Russia and Germany were affected by the migration that occurred in both countries over recent decades. However, our restricted focus in only adjusting for the migration of German repatriates and Jews had moderate effects on the national CVD mortality statistics in Germany (+1.0% and Russia (-0.6%. Conclusions The effects on CVD mortality rates due to migration in Germany and Russia were smaller than those due to secular economical changes. However, migration should still be considered as a factor influencing national mortality trends.

  1. Human Time Allocation in Time-based Analog of Concurrent Interval-ratio Schedules

    OpenAIRE

    TAJIMA, HIROYUKI

    1999-01-01

    Six undergraduates participated in concurrent-choice experiment with monetary reinforcers. Each subject was exposed to a time-based analog of concurrent variable-interval variable-ratio schedule with equal time interval values. The time-based analog of variable-interval schedule arranged reinforcers throughout the session, and delivered them while the schedule was chosen. The time-based analog of variable-ratio schedule arranged and immediately delivered reinforcers only while the schedule wa...

  2. Consequences of Base Time for Redundant Signals Experiments.

    Science.gov (United States)

    Townsend, James T; Honey, Christopher

    2007-08-01

    We report analytical and computational investigations into the effects of base time on the diagnosticity of two popular theoretical tools in the redundant signals literature: (1) the race model inequality and (2) the capacity coefficient. We show analytically and without distributional assumptions that the presence of base time decreases the sensitivity of both of these measures to model violations. We further use simulations to investigate the statistical power model selection tools based on the race model inequality, both with and without base time. Base time decreases statistical power, and biases the race model test toward conservatism. The magnitude of this biasing effect increases as we increase the proportion of total reaction time variance contributed by base time. We marshal empirical evidence to suggest that the proportion of reaction time variance contributed by base time is relatively small, and that the effects of base time on the diagnosticity of our model-selection tools are therefore likely to be minor. However, uncertainty remains concerning the magnitude and even the definition of base time. Experimentalists should continue to be alert to situations in which base time may contribute a large proportion of the total reaction time variance. PMID:18670591

  3. A COMPARATIVE STUDY OF FORECASTING MODELS FOR TREND AND SEASONAL TIME SERIES DOES COMPLEX MODEL ALWAYS YIELD BETTER FORECAST THAN SIMPLE MODELS

    Directory of Open Access Journals (Sweden)

    Suhartono Suhartono

    2005-01-01

    Full Text Available Many business and economic time series are non-stationary time series that contain trend and seasonal variations. Seasonality is a periodic and recurrent pattern caused by factors such as weather, holidays, or repeating promotions. A stochastic trend is often accompanied with the seasonal variations and can have a significant impact on various forecasting methods. In this paper, we will investigate and compare some forecasting methods for modeling time series with both trend and seasonal patterns. These methods are Winter's, Decomposition, Time Series Regression, ARIMA and Neural Networks models. In this empirical research, we study on the effectiveness of the forecasting performance, particularly to answer whether a complex method always give a better forecast than a simpler method. We use a real data, that is airline passenger data. The result shows that the more complex model does not always yield a better result than a simpler one. Additionally, we also find the possibility to do further research especially the use of hybrid model by combining some forecasting method to get better forecast, for example combination between decomposition (as data preprocessing and neural network model.

  4. The Effects of Inquiry-Based Integrated Information Literacy Instruction: Four-Year Trends

    Directory of Open Access Journals (Sweden)

    Lin Ching Chen

    2014-07-01

    Full Text Available The purpose of this study was to examine the effects of four-year integrated information literacy instruction via a framework of inquiry-based learning on elementary students’ memory and comprehension. Moderating factors of students’ academic achievement was another focus of this study. The subjects were 72 students who have participated in this study since they entered an elementary school in Chiayi district. This elementary school adopted the integrated information literacy instruction, designed by the researchers and elementary school teachers, and integrated it into various subject matters via a framework of inquiry-based learning, such as Super 3 and Big6 models. A series of inquiry-based integrated information literacy instruction has been implemented since the second semester of the subjects’ first grade. A total of seven inquiry learning projects has been implemented from grade one through grade four. Fourteen instruments were used as pretests and posttests to assess students’ factual recall and conceptual understanding of subject contents in different projects. The results showed that inquiry-based integrated information literacy instruction couldhelp students memorize facts and comprehend concepts of subject contents. Regardless ofacademic achievements, if students would like to devote their efforts to inquiry processes, their memory and comprehension of subject contents improvedeffectively. However, students of low-academic achievement might need more time to be familiar with the inquiry-based learning strategy.

  5. Evolución de la endemia de la lepra en Brasil Time trends of Hansen's disease in Brasil

    Directory of Open Access Journals (Sweden)

    Maria da Conceição Cavalcanti Magalhães

    2005-12-01

    Full Text Available La presente investigación se propone abordar la distribución territorial de la lepra en Brasil con el objetivo de identificar las regularidades de su diferenciación espacial y aportar conocimientos que permitan progresar en la comprensión de los procesos de su producción social. Fueron calculadas las tasas anuales de detección de casos, brutos y específicos, para las regiones y estados del país. La evolución espacio-temporal fue realizada mediante la construcción de series históricas. Se expone como substrato de los análisis una síntese sobre la distribución histórico-geográfica de la endemia en Brasil. La serie histórica del período 1960 - 2002, permite comparar las tasas de detección de las regiones, en la primera década, con las tasas más bajas, a excepción de la región Norte, que se destaca com la mayor detección. Todas las regiones elevan la detección a partir de la década del 70, siendo la Sul la de detección más baja. Las regiones Norte y Centro Oeste, mantienen las más altas detecciones de casos y los mayores incrementos, lo cual evidencia la desigual evolución regional de la endemia en el país. La permanencia histórica de elevada incidencia de la lepra en la región Norte, en el estado de Maranhão y Pernambuco en la región Nordeste, del estado de Paraná en la región Sul, así como relativamente bajas incidencias en el resto de esta última región, sugieren la existencia de contextos geográficos de diferente vulnerabilidad a la producción social de la lepra, y de nuevos componentes en la organización espacial en algunos territorios.The present investigation intends to study the territorial distribution of leprosy in Brazil in order to identify the regularities of its differentiation, and to contribute to the knowledge that allows progress in the understanding of the processes of its social production. Time trends of global and specific leprosy detection rates were calculated for regions and states

  6. Trends in Sepsis and Infection Sources in the United States. A Population-Based Study

    OpenAIRE

    Walkey, Allan J.; Lagu, Tara; Lindenauer, Peter K.

    2015-01-01

    Rationale: Stakeholders seek to monitor processes and outcomes of care among patients with sepsis, but use of administrative data for sepsis surveillance is controversial. Prior studies using only principal diagnoses from claims data have shown a trend of rising sepsis incidence with falling infection incidence, implying that administrative data are inaccurate for sepsis surveillance.

  7. Building the Youth Mentoring Knowledge Base: Publishing Trends and Coauthorship Networks

    Science.gov (United States)

    Blakeslee, Jennifer E.; Keller, Thomas E.

    2012-01-01

    Despite the long history and widespread popularity of youth mentoring, only in the past two decades has an academic literature emerged to support the development of program policies and practices. This study examines knowledge development in the field of youth mentoring, with special attention to trends in the number and nature of articles…

  8. Trends of pre-hospital emergency medical services activity over 10 years: a population-based registry analysis

    OpenAIRE

    Pittet V.; Burnand B.; Yersin B.; Carron P.N.

    2014-01-01

    BACKGROUND: The number of requests to pre-hospital emergency medical services (PEMS) has increased in Europe over the last 20 years, but epidemiology of PEMS interventions has little be investigated. The aim of this analysis was to describe time trends of PEMS activity in a region of western Switzerland. METHODS: Use of data routinely and prospectively collected for PEMS intervention in the Canton of Vaud, Switzerland, from 2001 to 2010. This Swiss Canton comprises approximately 10% of the wh...

  9. Time is on whose side? Time trends in the association between maternal social disadvantage and offspring fetal growth. A study of 1,409,339 births in Denmark 1981-2004

    DEFF Research Database (Denmark)

    Mortensen, Laust H; Diderichsen, Finn; Davey-Smith, George;

    2009-01-01

    OBJECTIVE: Fetal growth is highly socially patterned and is related to health across the life course, but how the social patterns of fetal growth change over time remains understudied. We examined the time trends in maternal social disadvantage in relation to fetal growth in the context of a univ......OBJECTIVE: Fetal growth is highly socially patterned and is related to health across the life course, but how the social patterns of fetal growth change over time remains understudied. We examined the time trends in maternal social disadvantage in relation to fetal growth in the context...... of a universal welfare state under changing macroeconomic conditions over a 24-year period. Design and settings: All births in Denmark 1981-2004. MAIN OUTCOME MEASURE: The association between maternal social disadvantage in relation to birth weight for gestational age z-scores over time were analysed using...... linear regression. RESULTS: All measures of social disadvantage were associated with decreased fetal growth (p

  10. Burden of cancer in Malawi; common types, incidence and trends: National population-based cancer registry

    Directory of Open Access Journals (Sweden)

    Msyamboza Kelias

    2012-03-01

    Full Text Available Abstract Background Cancer is a leading cause of morbidity and mortality worldwide with a majority of cases and deaths occurring in developing countries. While cancer of the lung, breast, colorectum, stomach and prostate are the most common types of cancer globally, in east and southern Africa these are less common and comprehensive data to inform policies are lacking. Methods Nationwide cancer registry was conducted between September and October 2010 in Malawi. New cancer cases registered from 2007 to 2010 were identified from hospital and clinic registers of 81 out of 84 health facilities providing cancer diagnosis, treatment or palliative care services. Demographic and cancer data were extracted from registers and case notes using a standard form. Results A total of 18,946 new cases of cancer were registered in Malawi from 2007-2010. Of these 55.9% were females, 7.2% were children aged less than 15 years, 76.5% were adults aged 15-59 years and 16.4% were elderly aged 60 years or more. Only 17.9% of the cases had histologically verified diagnosis, 33.2% were diagnosed clinically and 49.6% based on clinical and some investigations. Amongst females, cancer of the cervix was the commonest accounting for 45.4% of all cases followed by Kaposi sarcoma (21.1%, cancer of the oesophagus (8.2%, breast (4.6% and non-Hodgkin lymphoma (4.1%. In males, Kaposi sarcoma was the most frequent (50.7% then cancer of oesophagus (16.9%, non-Hodgkin lymphoma (7.8, prostate (4.0% and urinary bladder (3.7%. Age-standardised incidence rate per 100,000 population for all types of cancer in males increased from 31 in 1999-2002 to 56 in 2007-2010. In females it increased from 29 to 69. Kaposi sarcoma and cancer of the oesophagus, cervical cancer and Kaposi sarcoma were the main causes for the increased incidence in males and females respectively. It was estimated that, annually at least 8,151 new cases of cancer (all types occur in Malawi. Conclusions This study provided

  11. Trends in educational inequalities in old age mortality in Norway 1961−2009: a prospective register based population study

    Directory of Open Access Journals (Sweden)

    Moe Joakim Oliu

    2012-10-01

    Full Text Available Abstract Background The vast majority of deaths occur in older adults. Paradoxically, knowledge on long-term trends in mortality inequalities among the aged, and particularly for those aged 80 years and over, is sparse. The historical trends in size and impact of socioeconomic inequalities on old age mortality are important to monitor because they may give an indication on future burden of inequalities. We investigated trends in absolute and relative educational inequalities in old age mortality in Norway between 1961 and 2009. Methods We did a register-based population study covering the entire Norwegian population aged 65-94 in the years 1961−2009 (1,534,513 deaths and 29,312,351 person years at risk. By examining 1-year mortality rates by gender, age and educational level we estimated trends in mortality rate ratios and rate differences. Results On average, age-standardised absolute inequalities increased by 0.17 deaths per 1000 person-years per year in men (P Conclusions While relative educational inequalities in old age mortality increased for both genders, absolute educational inequalities increased only temporarily in men and changed little among women. Our study show the importance of including absolute measures in inequality research in order to present a more complete picture of the burden of inequalities to policy makers. As even in older ages, inequalities represent an unexploited potential to public health, old age inequalities will become increasingly important as many countries are facing aging populations.

  12. Phase synchronization based minimum spanning trees for analysis of financial time series with nonlinear correlations

    Science.gov (United States)

    Radhakrishnan, Srinivasan; Duvvuru, Arjun; Sultornsanee, Sivarit; Kamarthi, Sagar

    2016-02-01

    The cross correlation coefficient has been widely applied in financial time series analysis, in specific, for understanding chaotic behaviour in terms of stock price and index movements during crisis periods. To better understand time series correlation dynamics, the cross correlation matrices are represented as networks, in which a node stands for an individual time series and a link indicates cross correlation between a pair of nodes. These networks are converted into simpler trees using different schemes. In this context, Minimum Spanning Trees (MST) are the most favoured tree structures because of their ability to preserve all the nodes and thereby retain essential information imbued in the network. Although cross correlations underlying MSTs capture essential information, they do not faithfully capture dynamic behaviour embedded in the time series data of financial systems because cross correlation is a reliable measure only if the relationship between the time series is linear. To address the issue, this work investigates a new measure called phase synchronization (PS) for establishing correlations among different time series which relate to one another, linearly or nonlinearly. In this approach the strength of a link between a pair of time series (nodes) is determined by the level of phase synchronization between them. We compare the performance of phase synchronization based MST with cross correlation based MST along selected network measures across temporal frame that includes economically good and crisis periods. We observe agreement in the directionality of the results across these two methods. They show similar trends, upward or downward, when comparing selected network measures. Though both the methods give similar trends, the phase synchronization based MST is a more reliable representation of the dynamic behaviour of financial systems than the cross correlation based MST because of the former's ability to quantify nonlinear relationships among time

  13. Verifying real-time systems against scenario-based requirements

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Li, Shuhao; Nielsen, Brian;

    2009-01-01

    subset of the LSC language. By equivalently translating an LSC chart into an observer TA and then non-intrusively composing this observer with the original system model, the problem of verifying a real-time system against a scenario-based requirement reduces to a classical real-time model checking......We propose an approach to automatic verification of real-time systems against scenario-based requirements. A real-time system is modeled as a network of Timed Automata (TA), and a scenario-based requirement is specified as a Live Sequence Chart (LSC). We define a trace-based semantics for a kernel...

  14. Spatiotemporal trends in ground-level ozone concentrations and metrics in France over the time period 1999-2012.

    Science.gov (United States)

    Sicard, Pierre; Serra, Romain; Rossello, Philippe

    2016-08-01

    The hourly ozone (O3) data from 332 background monitoring stations, spread in France, were analyzed over the period 1999-2012 and short-term trends were calculated. In the current climate change context, the calculation of human health- and vegetation-relevant metrics, and of associated trends, provides a consistent method to establish proper and effective policies to reduce the adverse O3 effects. The generation of optimal O3 maps, for risk and exposure assessment, is challenging. To overcome this issue, starting from a set of stations, a hybrid regression-interpolation approach was proposed. Annual surface O3 metrics, O3 human health metrics (number of exceedances of daily maximum 8-h values greater than 60 ppb and SOMO35) and O3 vegetation impact metrics (AOT40 for vegetation and forests) were investigated at individual sites. Citizens are more exposed to high O3 levels in rural areas than people living in the cities. The annual mean concentrations decreased by -0.12ppbyear(-1) at rural stations, and the significant reduction at 67% of stations, particularly during the warm season, in the number of episodic high O3 concentrations (e.g. 98th percentile, -0.19ppbyear(-1)) can be associated with the substantial reductions in NOx and VOCs emissions in the EU-28 countries since the early 1990s Inversely, the O3 background level is rising at 76% of urban sites (+0.14ppbyear(-1)), particularly during the cold period. This rise can be attributed to increases in imported O3 by long-range transport and to a low O3 titration by NO due to the reduction in local NOx emissions. The decrease in health-related and vegetation-relevant O3 metrics, at almost all stations, is driven by decreases in regional photochemical O3 formation and in peak O3 concentrations. The short-term trends highlight that the threat to population and vegetation declined between 1999 and 2012 in France, demonstrating the success of European control strategies over the last 20 years. However, for all

  15. Timed-Release Hierarchical Identity-Based Encryption

    Directory of Open Access Journals (Sweden)

    Toru Oshikiri

    2014-11-01

    Full Text Available We propose a notion of hierarchical identity-based encryption (HIBE scheme with timed-release encryption (TRE mechanism, timed-release hierarchical identity-based encryption (TRHIBE, and define its security models. We also show a generic construction of TRHIBE from HIBE and one-time signature, and discuss the security of the constructed scheme.

  16. Recovery of delay time from time series based on the nearest neighbor method

    Science.gov (United States)

    Prokhorov, M. D.; Ponomarenko, V. I.; Khorev, V. S.

    2013-12-01

    We propose a method for the recovery of delay time from time series of time-delay systems. The method is based on the nearest neighbor analysis. The method allows one to reconstruct delays in various classes of time-delay systems including systems of high order, systems with several coexisting delays, and nonscalar time-delay systems. It can be applied to time series heavily corrupted by additive and dynamical noise.

  17. Recovery of delay time from time series based on the nearest neighbor method

    Energy Technology Data Exchange (ETDEWEB)

    Prokhorov, M.D., E-mail: mdprokhorov@yandex.ru [Saratov Branch of Kotel' nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences, Zelyonaya Street, 38, Saratov 410019 (Russian Federation); Ponomarenko, V.I. [Saratov Branch of Kotel' nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences, Zelyonaya Street, 38, Saratov 410019 (Russian Federation); Department of Nano- and Biomedical Technologies, Saratov State University, Astrakhanskaya Street, 83, Saratov 410012 (Russian Federation); Khorev, V.S. [Department of Nano- and Biomedical Technologies, Saratov State University, Astrakhanskaya Street, 83, Saratov 410012 (Russian Federation)

    2013-12-09

    We propose a method for the recovery of delay time from time series of time-delay systems. The method is based on the nearest neighbor analysis. The method allows one to reconstruct delays in various classes of time-delay systems including systems of high order, systems with several coexisting delays, and nonscalar time-delay systems. It can be applied to time series heavily corrupted by additive and dynamical noise.

  18. Emissions Trends, Labour Productivity Dynamics and Time-Related Events - Sector Heterogeneous Analyses of Decoupling/Recoupling on a 1990-2006 NAMEA

    OpenAIRE

    Marin, Giovanni; Mazzanti, Massimiliano

    2009-01-01

    This paper provides new empirical evidence on Environmental Kuznets Curves (EKC) for CO2 and air pollutants at sector level. A panel dataset based on the Italian NAMEA (National Accounting Matrix including Environmental Accounts) over 1990-2006 is analysed, focusing on both emissions efficiency (EKC model) and total emissions (IPAT model). Results show that, looking at sector evidence, both decoupling and also eventually re-coupling trends could emerge along the path of economic development. ...

  19. Time Trend of the People lost follow up on Antiretroviral Therapy (ART Services in Nepal: A Epidemiological Modelling

    Directory of Open Access Journals (Sweden)

    Brijesh Sathian

    2014-06-01

    Full Text Available Background: The real state about the spread of the HIV epidemic in Nepal is not clear since the details available are on the basis of repeated integrated biological and behavioral surveillance. Objective To study the trends of People lost follow up on ART in future. Material and methods: A retrospective study was carried out on the data collected from the Health ministry records of Nepal, between 2006 and 2012. Descriptive statistics and statistical modelling were used for the analysis and forecasting of data. Results: Including the constant term from the equation, the quadratic model was the best fit, for the forecasting of People lost follow up on ART. Using quadratic equation, it is estimated that 4331 reported number of People lost follow up on ART will be there in Nepal by the year 2020. Conclusion: The People lost follow up on ART in Nepal are having an increasing trend. Estimates of the total number of People lost follow up on ART attributable to the major routes of infection make an important contribution to public health policy. They can be used for the planning of healthcare services and for contributing to estimates of the future numbers with People lost follow up on ART used for planning health promotion programmes.

  20. Monitoring Trends in Light Pollution in China Based on Nighttime Satellite Imagery

    OpenAIRE

    Pengpeng Han; Jinliang Huang; Rendong Li; Lihui Wang; Yanxia Hu; Jiuling Wang; Wei Huang

    2014-01-01

    China is the largest developing country worldwide, with rapid economic growth and the highest population. Light pollution is an environmental factor that significantly influences the quality and health of wildlife, as well as the people of any country. The objective of this study is to model the light pollution spatial pattern, and monitor changes in trends of spatial distribution from 1992 to 2012 in China using nighttime light imagery from the Defense Meteorological Satellite Program Operat...

  1. Trend of dengue virus infection at Lucknow, north India (2008- 2010): A hospital based study

    OpenAIRE

    Pandey, Nidhi; Nagar, Rachna; Gupta, Shikha; Omprakash,; Khan, Danish; Singh, Desh Deepak; Mishra, Gitika; Prakash, Shantanu; Singh, K. P.; Singh, Mastan; Jain, Amita

    2012-01-01

    Background & objectives: Dengue virus (DV) infection has emerged as a major health problem in north India. Here, we report the annual trend of dengue virus infection as seen in Lucknow, Uttar Pradesh, during 2008-2010. Methods: Blood samples from clinically suspected cases of dengue virus infection were collected and history was taken on structured clinical data sheet. All samples were tested for dengue IgM by antibody capture ELISA. Selected samples were tested by conventional RT-PCR for den...

  2. Antarctic station-based seasonal pressure reconstructions since 1905: 2. Variability and trends during the twentieth century

    Science.gov (United States)

    Fogt, Ryan L.; Jones, Julie M.; Goergens, Chad A.; Jones, Megan E.; Witte, Grant A.; Lee, Ming Yueng

    2016-03-01

    The Antarctic seasonal station-based pressure reconstructions evaluated in our companion paper are evaluated here to provide additional knowledge on Antarctic pressure variability during the twentieth century. In the period from 1905 to 1956, we find that the Hadley Centre gridded sea level pressure data set compared the best with our reconstructions, perhaps due to similar methods to estimate pressure without direct observations. The primary focus on the twentieth century Antarctic pressure variability was in summer and winter, as these were the seasons with the highest reconstruction skill. In summer, there is considerable interannual variability that was spatially uniform across all of Antarctica. Notable high pressure anomalies were found in the summers of 1911/1912 and 1925/1926; both summers correspond to negative phases of the Southern Annular Mode as well as El Niño events in the tropical Pacific. In addition, negative summer pressure trends during the last ~40 years across all of Antarctica are unique in the context of 30 year trends throughout the entire twentieth century, suggesting a strong component of anthropogenic forcing on the recent summer trends. In contrast, mean winter pressure is less variable from year to year during the early twentieth century, and there is less similarity between the pressure variations along the Antarctic Peninsula compared to the rest of the continent. No significant pressure trends were found consistently across all Antarctica (although some significant regional trends can be identified), and low-frequency, multidecadal-scale variability appears to dominate the historical pressure variations in this season.

  3. A two warehouse deterministic inventory model for deteriorating items with a linear trend in time dependent demand over finite time horizon by Elitist Real-Coded Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    A.K. Bhunia

    2013-04-01

    Full Text Available This paper deals with a deterministic inventory model developed for deteriorating items having two separate storage facilities (owned and rented warehouses due to limited capacity of the existing storage (owned warehouse with linear time dependent demand (increasing over a fixed finite time horizon. The model is formulated with infinite replenishment and the successive replenishment cycle lengths are in arithmetic progression. Partially backlogged shortages are allowed. The stocks of rented warehouse (RW are transported to the owned warehouse (OW in continuous release pattern. For this purpose, the model is formulated as a constrained non-linear mixed integer programming problem. For solving the problem, an advanced genetic algorithm (GA has been developed. This advanced GA is based on ranking selection, elitism, whole arithmetic crossover and non-uniform mutation dependent on the age of the population. Our objective is to determine the optimal replenishment number, lot-size of two-warehouses (OW and RW by maximizing the profit function. The model is illustrated with four numerical examples and sensitivity analyses of the optimal solution are performed with respect to different parameters.

  4. Ground Displacement Trends in an Urban Environment Using Multi-Temporal InSAR Analysis and Two Decades of Multi-Sensor Satellite-Based SAR Imagery

    Science.gov (United States)

    Armas, Iuliana; Necsoiu, Marius; Mendes, Diana Aldea; Gheorghe, Mihaela; Gheorghe, Diana

    2015-05-01

    This exploratory research used three sets of single polarized synthetic aperture radar (SAR) satellite data and a multi-temporal radar interferometry (InSAR) methodology to determine the spatial evolution and ground displacement trends of several industrial parks located in the metropolitan area of Bucharest, Romania. From 70candidate areas, 20 large industrial parks were selected for analysis and interpretation. InSAR analysis used SAR data acquired between 1992 and 2014 by ERS-1/-2, ENVISAT, and TerraSAR-X satellites. Ground movement patterns identified before and after 2000 were linked to groundwater table investigations based on 25 water wells, located on or in the proximity of these areas. The analysis revealed an initial subsidence or no change in uplift areas before 2000, followed by a return to zonal movement. This trend may also be related to the shutting down of industries that consumed large amounts of water, which increased deep groundwater pressure. Only one continuous subsidence trend was identified for an industrial area located south of the city, an area which continues to be active over time. Ongoing research is focused on using traditional geological andgeomorphologic investigations, as well as comparisons with fieldGlobal Navigation Satellite System (GNSS) data.

  5. Contrasting trends in light pollution across Europe based on satellite observed night time lights

    OpenAIRE

    Bennie, Jonathan; Davies, Thomas W; Duffy, James P.; Inger, Richard; Gaston, Kevin J

    2014-01-01

    Since the 1970s nighttime satellite images of the Earth from space have provided a striking illustration of the extent of artificial light. Meanwhile, growing awareness of adverse impacts of artificial light at night on scientific astronomy, human health, ecological processes and aesthetic enjoyment of the night sky has led to recognition of light pollution as a significant global environmental issue. Links between economic activity, population growth and artificial light are well documented ...

  6. Image-Based Learning Approach Applied to Time Series Forecasting

    OpenAIRE

    J. C. Chimal-Eguía; K. Ramírez-Amáro

    2012-01-01

    In this paper, a new learning approach based on time-series image information is presented. In order to implementthis new learning technique, a novel time-series input data representation is also defined. This input data representation is based on information obtained by image axis division into boxes. The difference between this new input data representation and the classical is that this technique is not time-dependent. This new information is implemented in the new Image-Based Learning A...

  7. Time trends: a ten-year comparison (2005–2015) of pedometer-determined physical activity and obesity in Czech preschool children

    OpenAIRE

    Sigmund, Erik; Sigmundová, Dagmar; Badura, Petr; Trhlíková, Lucie; Gecková, Andrea Madarasová

    2016-01-01

    Background To explore the time trends (2005–2015) of pedometer-determined weekday and weekend physical activity (PA) and obesity prevalence in 4–7-year-old Czech preschool children and changes in proportion of kindergarten vs. leisure-time PA. Methods The study compared data of two cross-sectional cohorts of preschool children (2005: 92 boys and 84 girls; 2015: 105 boys and 87 girls) in the Czech Republic, using the same measurements and procedures in both cases. PA was monitored by the Yamax...

  8. Dynamic Programming based Time-Delay Estimation (TDE) Technique for Analysis of Time-varying Time-delay

    CERN Document Server

    Gupta, Deepak K; Fonck, Raymond R

    2008-01-01

    A new time-delay estimation (TDE) technique based on dynamic programming is developed, to measures the time-varying time-delay between two signals. Dynamic programming based TDE technique provides a frequency response 5 to 10 times higher than previously known TDE techniques, namely those based on time-lag cross-correlation or wavelet analysis. Effects of frequency spectrum, signal-to-noise ratio and amplitude of time-delay on response (represented as transfer function) of TDE technique is studied using simulated data signals. Transfer function for the technique decreases with increase in noise in signal; however it is independent of signal spectrum shape. Dynamic programming based TDE technique is applied to the Beam-Emission-Spectroscopy (BES) diagnostic data to measure poloidal velocity fluctuations, which led to the observation of theoretically predicted zonal flows in high-temperature tokamak plasmas.

  9. Dynamic programming based time-delay estimation technique for analysis of time-varying time-delay

    International Nuclear Information System (INIS)

    A new time-delay estimation (TDE) technique based on dynamic programming is developed to measure the time-varying time-delay between two signals. The dynamic programming based TDE technique provides a frequency response five to ten times better than previously known TDE techniques, namely, those based on time-lag cross-correlation or wavelet analysis. Effects of frequency spectrum, signal-to-noise ratio, and amplitude of time-delay on response of the TDE technique (represented as transfer function) are studied using simulated data signals. The transfer function for the technique decreases with increase in noise in signal; however it is independent of signal spectrum shape. The dynamic programming based TDE technique is applied to the beam emission spectroscopy diagnostic data to measure poloidal velocity fluctuations, which led to the observation of theoretically predicted zonal flows in high-temperature tokamak plasmas.

  10. Time trends in pediatric hospitalizations for hepatitis A in Greece (1999-2013): Assessment of the impact of universal infant immunization in 2008.

    Science.gov (United States)

    Papaevangelou, V; Alexopoulou, Z; Hadjichristodoulou, C; Kourlamba, G; Katsioulis, A; Theodoridou, K; Spoulou, V; Theodoridou, M

    2016-07-01

    Hepatitis A vaccine was introduced in the Greek National Immunization Program in 2008. To estimate possible impact of the universal vaccination implementation, time trends of hospitalizations for hepatitis A at the Infectious Diseases Unit of a Tertiary Pediatric Hospital in Athens during 1999-2013 were analyzed. Hepatitis A hospitalizations were recorded from the discharge database and were expressed as frequencies and rate of annual departmental hospitalizations. Time series analysis (ARIMA) was used to explore trends and the impact of the vaccination. Moreover, changes in patient age, population group distribution and the duration of hospitalization were also examined. Hepatitis A hospitalizations rate significantly decreased between pre-vaccination (1999-2008) and post-vaccination (2009-2013) era from 50.5 to 20.8/1000 hospitalizations (p = 0.005). A 3-year periodicity and a trend of reduction on hepatitis A hospitalizations rates across years were noted. Roma children had significant higher rates of hepatitis A hospitalization, followed by immigrant children. Importantly, possibly due to preceding vaccine availability with considerable uptake in private market and unvaccinated group/pockets of children (Roma), overall vaccination effect was less apparent when compared to data from other countries that implemented universal vaccination. No significant change in patient age, population group distribution, or duration of hospitalization was observed. High risk groups such as Roma children should be targeted for vaccination to reduce future outbreaks.

  11. Time trends in pediatric hospitalizations for hepatitis A in Greece (1999-2013): Assessment of the impact of universal infant immunization in 2008.

    Science.gov (United States)

    Papaevangelou, V; Alexopoulou, Z; Hadjichristodoulou, C; Kourlamba, G; Katsioulis, A; Theodoridou, K; Spoulou, V; Theodoridou, M

    2016-07-01

    Hepatitis A vaccine was introduced in the Greek National Immunization Program in 2008. To estimate possible impact of the universal vaccination implementation, time trends of hospitalizations for hepatitis A at the Infectious Diseases Unit of a Tertiary Pediatric Hospital in Athens during 1999-2013 were analyzed. Hepatitis A hospitalizations were recorded from the discharge database and were expressed as frequencies and rate of annual departmental hospitalizations. Time series analysis (ARIMA) was used to explore trends and the impact of the vaccination. Moreover, changes in patient age, population group distribution and the duration of hospitalization were also examined. Hepatitis A hospitalizations rate significantly decreased between pre-vaccination (1999-2008) and post-vaccination (2009-2013) era from 50.5 to 20.8/1000 hospitalizations (p = 0.005). A 3-year periodicity and a trend of reduction on hepatitis A hospitalizations rates across years were noted. Roma children had significant higher rates of hepatitis A hospitalization, followed by immigrant children. Importantly, possibly due to preceding vaccine availability with considerable uptake in private market and unvaccinated group/pockets of children (Roma), overall vaccination effect was less apparent when compared to data from other countries that implemented universal vaccination. No significant change in patient age, population group distribution, or duration of hospitalization was observed. High risk groups such as Roma children should be targeted for vaccination to reduce future outbreaks. PMID:27141813

  12. X-Ray Pulsar Based Navigation and Time Determination Project

    Data.gov (United States)

    National Aeronautics and Space Administration — DARPA recently initiated the XNAV program to undertake development of GPS independent, precision navigation and time determination based on observations of certain...

  13. Cross-national time trends in bullying behaviour 1994-2006: findings from Europe and North America

    DEFF Research Database (Denmark)

    Molcho, Michal; Craig, Wendy; Due, Pernille;

    2009-01-01

    OBJECTIVES: To identify trends over 12 years in the prevalence of bullying and associated victimization among adolescents in North American and European countries. METHODS: Cross-sectional self-report surveys were obtained from nationally representative samples of 11-15 year old school children...... in 21 countries in 1993/94 and in 27 countries in each of 1997/98, 2001/02 and 2005/06. Measures included involvement in bullying as either a perpetrator and/or victim. RESULTS: Consistent decreases in the prevalence of bullying were reported between 1993/94 to 2005/06 in most countries. Geographic...... patterns show consistent decreases in bullying in Western European countries and in most Eastern European countries. An increase or no change in prevalence was evident in almost all English speaking countries participating in the study (England, Scotland, Wales, Ireland and Canada, but not in the USA...

  14. Providing web-based tools for time series access and analysis

    Science.gov (United States)

    Eberle, Jonas; Hüttich, Christian; Schmullius, Christiane

    2014-05-01

    Time series information is widely used in environmental change analyses and is also an essential information for stakeholders and governmental agencies. However, a challenging issue is the processing of raw data and the execution of time series analysis. In most cases, data has to be found, downloaded, processed and even converted in the correct data format prior to executing time series analysis tools. Data has to be prepared to use it in different existing software packages. Several packages like TIMESAT (Jönnson & Eklundh, 2004) for phenological studies, BFAST (Verbesselt et al., 2010) for breakpoint detection, and GreenBrown (Forkel et al., 2013) for trend calculations are provided as open-source software and can be executed from the command line. This is needed if data pre-processing and time series analysis is being automated. To bring both parts, automated data access and data analysis, together, a web-based system was developed to provide access to satellite based time series data and access to above mentioned analysis tools. Users of the web portal are able to specify a point or a polygon and an available dataset (e.g., Vegetation Indices and Land Surface Temperature datasets from NASA MODIS). The data is then being processed and provided as a time series CSV file. Afterwards the user can select an analysis tool that is being executed on the server. The final data (CSV, plot images, GeoTIFFs) is visualized in the web portal and can be downloaded for further usage. As a first use case, we built up a complimentary web-based system with NASA MODIS products for Germany and parts of Siberia based on the Earth Observation Monitor (www.earth-observation-monitor.net). The aim of this work is to make time series analysis with existing tools as easy as possible that users can focus on the interpretation of the results. References: Jönnson, P. and L. Eklundh (2004). TIMESAT - a program for analysing time-series of satellite sensor data. Computers and Geosciences 30

  15. Trends in Nanomaterial-Based Non-Invasive Diabetes Sensing Technologies

    Directory of Open Access Journals (Sweden)

    Prashanth Makaram

    2014-04-01

    Full Text Available Blood glucose monitoring is considered the gold standard for diabetes diagnostics and self-monitoring. However, the underlying process is invasive and highly uncomfortable for patients. Furthermore, the process must be completed several times a day to successfully manage the disease, which greatly contributes to the massive need for non-invasive monitoring options. Human serums, such as saliva, sweat, breath, urine and tears, contain traces of glucose and are easily accessible. Therefore, they allow minimal to non-invasive glucose monitoring, making them attractive alternatives to blood measurements. Numerous developments regarding noninvasive glucose detection techniques have taken place over the years, but recently, they have gained recognition as viable alternatives, due to the advent of nanotechnology-based sensors. Such sensors are optimal for testing the amount of glucose in serums other than blood thanks to their enhanced sensitivity and selectivity ranges, in addition to their size and compatibility with electronic circuitry. These nanotechnology approaches are rapidly evolving, and new techniques are constantly emerging. Hence, this manuscript aims to review current and future nanomaterial-based technologies utilizing saliva, sweat, breath and tears as a diagnostic medium for diabetes monitoring.

  16. Prevalence and Trends of Staphylococcus aureus Bacteraemia in Hospitalized Patients in South Africa, 2010 to 2012: Laboratory-Based Surveillance Mapping of Antimicrobial Resistance and Molecular Epidemiology.

    Directory of Open Access Journals (Sweden)

    Olga Perovic

    Full Text Available We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB.Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST.S. aureus from 2709 patients were included, and 1231 (46% were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003. Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001. Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01. The most prevalent SCCmec type was SCCmec type III (531 [41%] followed by type IV (402 [31%]. Spa-typing discovered 47 different spa-types. The five (87% most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8 (n = 7 followed by ST5 (CC5 (n = 4, ST36 (CC30 (n = 4 and ST239 (CC8 (n = 3.MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41% and type IV (31%, which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB.

  17. Seasonal changes in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas: General trends based on field survey data 1959-2009

    Science.gov (United States)

    Yang, Shu; Han, Xiurong; Zhang, Chuansong; Sun, Baiye; Wang, Xiulin; Shi, Xiaoyong

    2014-12-01

    The characteristics of seasonal variation in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas were discussed based on field investigation data from 1959 to 2009. The field data from 1981 to 2004 showed that the Chlorophyll- a concentration in surface seawater was between 0.4 and 8.5 μg dm-3. The seasonal changes generally presented a bimodal trend, with the biomass peaks occurring in May and August, and Chlorophyll-a concentration was the lowest in winter. Seasonal biomass changes were mainly controlled by temperature and nutrient levels. From the end of autumn to the next early spring, phytoplankton biomass was mainly influenced by temperature, and in other seasons, nutrient level (including the nutrient supply from the terrestrial runoffs) was the major influence factor. Field investigation data from 1959 to 2009 demonstrated that diatoms were the main phytoplankton in this area, and Skeletonema costatum, Pseudo-nitzschia pungens, Coscinodiscus oculus-iridis, Thalassinoema nitzschioides, Paralia sulcata, Chaetoceros lorenzianus, Chaetoceros curvisetus, and Prorocentrum donghaiense Lu were common dominant species. The seasonal variations in major dominant phytoplankton species presented the following trends: 1) Skeletonema (mainly S. costatum) was dominant throughout the year; and 2) seasonal succession trends were Coscinodiscus (spring) → Chaetoceros (summer and autumn) → Coscinodiscus (winter). The annual dominance of S. costatum was attributed to its environmental eurytopicity and long standing time in surface waters. The seasonal succession of Coscinodiscus and Chaetoceros was associated with the seasonal variation in water stability and nutrient level in this area. On the other hand, long-term field data also indicated obvious interannual variation of phytoplankton biomass and community structure in the Changjiang River Estuary and adjacent seas: average annual phytoplankton biomass and dinoflagellate

  18. Prevalence and Trends of Staphylococcus aureus Bacteraemia in Hospitalized Patients in South Africa, 2010 to 2012: Laboratory-Based Surveillance Mapping of Antimicrobial Resistance and Molecular Epidemiology

    Science.gov (United States)

    Perovic, Olga; Iyaloo, Samantha; Kularatne, Ranmini; Lowman, Warren; Bosman, Noma; Wadula, Jeannette; Seetharam, Sharona; Duse, Adriano; Mbelle, Nontombi; Bamford, Colleen; Dawood, Halima; Mahabeer, Yesholata; Bhola, Prathna; Abrahams, Shareef; Singh-Moodley, Ashika

    2015-01-01

    Introduction We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB). Methods Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST). Results S. aureus from 2709 patients were included, and 1231 (46%) were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003). Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001). Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01). The most prevalent SCCmec type was SCCmec type III (531 [41%]) followed by type IV (402 [31%]). Spa-typing discovered 47 different spa-types. The five (87%) most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8) (n = 7) followed by ST5 (CC5) (n = 4), ST36 (CC30) (n = 4) and ST239 (CC8) (n = 3). Conclusions MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41%) and type IV (31%), which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB. PMID:26719975

  19. Trends in health facility based maternal mortality in Central Region, Kenya: 2008-2012

    Science.gov (United States)

    Muchemi, Onesmus Maina; Gichogo, Agnes Wangechi; Mungai, Jane Githuku; Roka, Zeinab Gura

    2016-01-01

    Introduction WHO classifies Kenya as having a high maternal mortality. Regional data on maternal mortality trends is only available in selected areas. This study reviewed health facility maternal mortality trends, causes and distribution in Central Region of Kenya, 2008-2012. Methods We reviewed health records from July 2008 to June 2012. A maternal death was defined according to ICD-10 criterion. The variables reviewed included socio-demographic, obstetric characteristics, reasons for admission, causes of death and contributing factors. We estimated maternal mortality ratio for each year and overall for the four year period using a standard equation and used frequencies means/median and proportions for other descriptive variables. Results A total 421 deaths occurred among 344,191 live births; 335(80%) deaths were audited. Maternal mortality ratios were: 127/100,000 live births in 2008/09; 124/100,000 live births in 2009/2010; 129/100,000 live births in 2010/2011 and 111/100,000 live births in 2011/2012. Direct causes contributed majority of deaths (77%, n=234) including hemorrhage, infection and pre-eclampsia/eclampsia. Mean age was 30(±6) years; 147(71%) attended less than four antenatal visits and median gestation at birth was 38 weeks (IQR=9). One hundred ninety (59%) died within 24 hours after admission. There were 111(46%) caesarian births, 95(39%) skilled vaginal, 31(13%) unskilled 5(2%) vacuum deliveries and 1(<1%) destructive operation. Conclusion The region recorded an unsteady declining trend. Direct causes contributed to the majority deaths including hemorrhage, infection and pre-eclampsia/eclampsia. We recommend health education on individualized birth plan and mentorship on emergency obstetric care. Further studies are necessary to clarify and expand the findings of this study. PMID:27516824

  20. A global process-based study of marine CCN trends and variability

    Directory of Open Access Journals (Sweden)

    E. M. Dunne

    2014-12-01

    Full Text Available Low-level clouds have a strong climate-cooling effect in oceanic regions due to the much lower albedo of the underlying sea surface. Marine clouds typically have low droplet concentrations, making their radiative properties susceptible to changes in cloud condensation nucleus (CCN concentrations. Here, we use the global aerosol model GLOMAP to investigate the processes that determine variations in marine CCN concentrations, and focus especially on the effects of previously identified wind speed trends in recent decades. Although earlier studies have found a link between linear wind speed trends and CCN concentration, we find that the effects of wind speed trends identified using a dynamic linear model in the Northern Equatorial Pacific (0.56 m s−1 per decade in the period 1990–2004 and the North Atlantic (−0.21 m s−1 per decade are largely dampened by other processes controlling the CCN concentration, namely nucleation scavenging and transport of continental pollution. A CCN signal from wind speed change is seen only in the most pristine of the studied regions, i.e. over the Southern Ocean, where we simulate 3.4 cm−3 and 0.17 m s−1 increases over the 15-year period in the statistical mean levels of CCN and wind speed, respectively. Our results suggest that future changes in wind-speed-driven aerosol emissions from the oceans can probably have a climate feedback via clouds only in the most pristine regions. On the other hand, a feedback mechanism via changing precipitation patterns and intensities could take place over most oceanic regions, as we have shown that nucleation scavenging has by far the largest absolute effect on CCN concentrations.

  1. A global process-based study of marine CCN trends and variability

    Directory of Open Access Journals (Sweden)

    E. M. Dunne

    2014-06-01

    Full Text Available Low-level clouds have a strong climate-cooling effect in oceanic regions due to the much lower albedo of the underlying sea surface. Marine clouds typically have low droplet concentrations, making their radiative properties susceptible to changes in cloud condensation nucleus (CCN concentrations. Here, we use the global aerosol model GLOMAP to investigate the processes that determine variations in marine CCN concentrations, and focus especially on the effects of previously identified wind speed trends in recent decades. Although earlier studies have found a link between linear wind speed trends and CCN concentration, we find that the effects of wind speed trends identified using a dynamic linear model in the Northern Equatorial Pacific (0.56 m s−1 per decade in the period 1990–2004 and the North Atlantic (−0.21 m s−1 per decade are largely dampened by other processes controlling the CCN concentration, namely nucleation scavenging and transport of continental pollution. A CCN signal from wind speed change is seen only in the most pristine of the studied regions, i.e. over the Southern Ocean, where we simulate 3.4 cm−3 and 0.17 m s−1 increases over the fifteen-year period in the statistical mean levels of CCN and wind speed, respectively. Our results suggest that future changes in wind-speed-driven aerosol emissions from the oceans can probably have a climate feedback via clouds only in the most pristine regions. On the other hand, a feedback mechanism via changing precipitation patterns and intensities could take place over most oceanic regions, as we have shown that nucleation scavenging has by far the largest absolute effect on CCN concentrations.

  2. Neural Network Based Finite-Time Stabilization for Discrete-Time Markov Jump Nonlinear Systems with Time Delays

    OpenAIRE

    Fei Chen; Fei Liu; Hamid Reza Karimi

    2013-01-01

    This paper deals with the finite-time stabilization problem for discrete-time Markov jump nonlinear systems with time delays and norm-bounded exogenous disturbance. The nonlinearities in different jump modes are parameterized by neural networks. Subsequently, a linear difference inclusion state space representation for a class of neural networks is established. Based on this, sufficient conditions are derived in terms of linear matrix inequalities to guarantee stochastic finite-time boundedne...

  3. Mapping long-term changes in savannah crop productivity in Senegal through trend analysis of time-series of remote sensing data

    DEFF Research Database (Denmark)

    Tøttrup, Christian; Rasmussen, Michael Schultz

    2004-01-01

    Remote sensing, NDVI, trend analysis, environmental change, rainfall, land cover change, Senegal......Remote sensing, NDVI, trend analysis, environmental change, rainfall, land cover change, Senegal...

  4. Super-High Resolution Time Interval Measurement Method Based on Time-Space Relationships

    Institute of Scientific and Technical Information of China (English)

    DU Bao-Qiang; ZHOU Wei

    2009-01-01

    Based on the principle of quantized delay-time, a super-high resolution time interval measurement method is proposed based on time-space relationships.Using the delay-time stability that time and frequency signal travel in a specific medium, the measured time interval can be quantized.Combined with the phase coincidence detection technique, the measurement of time can be changed into the measurement of space length.The resolution and the stability of the measurement system are easily improved.Experimental results show that the measurement resolution of the measured time interval depends on the length difference of the double delay-time unit.When the length difference is set up on millimeter level or sub-millimeter level, super-high measurement resolution from hundreds of picosecond to tens of picosecond can be obtained.

  5. Time-to-digital converter based on analog time expansion for 3D time-of-flight cameras

    Science.gov (United States)

    Tanveer, Muhammad; Nissinen, Ilkka; Nissinen, Jan; Kostamovaara, Juha; Borg, Johan; Johansson, Jonny

    2014-03-01

    This paper presents an architecture and achievable performance for a time-to-digital converter, for 3D time-of-flight cameras. This design is partitioned in two levels. In the first level, an analog time expansion, where the time interval to be measured is stretched by a factor k, is achieved by charging a capacitor with current I, followed by discharging the capacitor with a current I/k. In the second level, the final time to digital conversion is performed by a global gated ring oscillator based time-to-digital converter. The performance can be increased by exploiting its properties of intrinsic scrambling of quantization noise and mismatch error, and first order noise shaping. The stretched time interval is measured by counting full clock cycles and storing the states of nine phases of the gated ring oscillator. The frequency of the gated ring oscillator is approximately 131 MHz, and an appropriate stretch factor k, can give a resolution of ≍ 57 ps. The combined low nonlinearity of the time stretcher and the gated ring oscillator-based time-to-digital converter can achieve a distance resolution of a few centimeters with low power consumption and small area occupation. The carefully optimized circuit configuration achieved by using an edge aligner, the time amplification property and the gated ring oscillator-based time-to-digital converter may lead to a compact, low power single photon configuration for 3D time-of-flight cameras, aimed for a measurement range of 10 meters.

  6. Criterion-based laparoscopic training reduces total training time

    NARCIS (Netherlands)

    Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.

    2011-01-01

    The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (

  7. Criterion-based laparoscopic training reduces total training time

    NARCIS (Netherlands)

    Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.

    2012-01-01

    The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (

  8. Estimating Reliability of Disturbances in Satellite Time Series Data Based on Statistical Analysis

    Science.gov (United States)

    Zhou, Z.-G.; Tang, P.; Zhou, M.

    2016-06-01

    Normally, the status of land cover is inherently dynamic and changing continuously on temporal scale. However, disturbances or abnormal changes of land cover — caused by such as forest fire, flood, deforestation, and plant diseases — occur worldwide at unknown times and locations. Timely detection and characterization of these disturbances is of importance for land cover monitoring. Recently, many time-series-analysis methods have been developed for near real-time or online disturbance detection, using satellite image time series. However, the detection results were only labelled with "Change/ No change" by most of the present methods, while few methods focus on estimating reliability (or confidence level) of the detected disturbances in image time series. To this end, this paper propose a statistical analysis method for estimating reliability of disturbances in new available remote sensing image time series, through analysis of full temporal information laid in time series data. The method consists of three main steps. (1) Segmenting and modelling of historical time series data based on Breaks for Additive Seasonal and Trend (BFAST). (2) Forecasting and detecting disturbances in new time series data. (3) Estimating reliability of each detected disturbance using statistical analysis based on Confidence Interval (CI) and Confidence Levels (CL). The method was validated by estimating reliability of disturbance regions caused by a recent severe flooding occurred around the border of Russia and China. Results demonstrated that the method can estimate reliability of disturbances detected in satellite image with estimation error less than 5% and overall accuracy up to 90%.

  9. Building Real-Time Network Intrusion Detection System Based on Parallel Time-Series Mining Techniques

    Institute of Scientific and Technical Information of China (English)

    Zhao Feng; Li Qinghua

    2005-01-01

    A new real-time model based on parallel time-series mining is proposed to improve the accuracy and efficiency of the network intrusion detection systems. In this model, multidimensional dataset is constructed to describe network events, and sliding window updating algorithm is used to maintain network stream. Moreover, parallel frequent patterns and frequent episodes mining algorithms are applied to implement parallel time-series mining engineer which can intelligently generate rules to distinguish intrusions from normal activities. Analysis and study on the basis of DAWNING 3000 indicate that this parallel time-series mining-based model provides a more accurate and efficient way to building real-time NIDS.

  10. Highly comparative, feature-based time-series classification

    CERN Document Server

    Fulcher, Ben D

    2014-01-01

    A highly comparative, feature-based approach to time series classification is introduced that uses an extensive database of algorithms to extract thousands of interpretable features from time series. These features are derived from across the scientific time-series analysis literature, and include summaries of time series in terms of their correlation structure, distribution, entropy, stationarity, scaling properties, and fits to a range of time-series models. After computing thousands of features for each time series in a training set, those that are most informative of the class structure are selected using greedy forward feature selection with a linear classifier. The resulting feature-based classifiers automatically learn the differences between classes using a reduced number of time-series properties, and circumvent the need to calculate distances between time series. Representing time series in this way results in orders of magnitude of dimensionality reduction, allowing the method to perform well on ve...

  11. Incidence Patterns and Trends of non-Central Nervous System Solid Tumours in Children and Adolescents. A Collaborative Study of the Spanish Population Based Cancer Registries

    Science.gov (United States)

    Larrañaga, Nerea; Sanchez, Mª José; Ardanaz, Eva; Felipe, Saray; Marcos-Gragera, Rafael; Ramos, María; Carulla, Marià; Chirlaque, Mª Dolores; Argüelles, Marcial V.; Martos, Carmen; Mateo, Antonio; Peris-Bonet, Rafael

    2016-01-01

    Objective: To describe incidence patterns and trends in children (0-14 years) and adolescents (15-19 age-range) with solid tumours, except those of central nervous system (CNS), in Spain. Methods: Cases were drawn from eleven Spanish population-based cancer registries. Incidence was estimated for the period 1983-2007 and trends were evaluated using Joinpoint regression analysis. Results: The studied tumour groups accounted for 36% of total childhood cancers and 47.6% of those diagnosed in adolescence with annual rates per million of 53.5 and 89.3 respectively. In children 0 to 14 years of age, Neuroblastoma (NB) was the commonest (7.8%) followed by Soft-tissue sarcomas (STS) (6.3%), bone tumours (BT) (6.2%) and renal tumours (RT) (4.5%). NB was the most frequently diagnosed tumour before the 5th birthday, while STS and BT were the commonest at 5-9 years of age, and BT and Carcinoma and other epithelial tumours (COET) at 10-14. COET presented the highest incidence in adolescents, followed by germ-cell tumours (GCT), BT and STS. These four diagnostic groups accounted for 94% of total non-CNS solid tumours, in adolescents. Overall incidence rates increased significantly in children up to 1996 with an annual percentage change (APC) of 2.6% (95%CI: 1.7; 3.6). NB and COET showed significant time trend (APCs: 1.4% and 3.8% respectively) while other tumour groups such as RT, STS, BT or GCT had no significant changes over time. A significant increase was present in NB under the age of 5 and in BT and STS in children aged 10-14 years. In adolescents there were significant increases for all tumours combined (APC=2.7; 95%CI: 1.8-3.6) and for STS, GCT and COET (APCs: 3.2%, 4.4% and 3.5% respectively), while other tumour groups such as hepatic tumours, BT or thyroid carcinomas showed a decreasing trend or no increase. Conclusions: Overall, the incidence of the studied cancers in children increased along the period 1983-1996 with no posterior significant rise, while the incidence

  12. A Citation-Based Analysis and Review of Significant Papers on Timing and Time Perception

    Science.gov (United States)

    Teki, Sundeep

    2016-01-01

    Time is an important dimension of brain function, but little is yet known about the underlying cognitive principles and neurobiological mechanisms. The field of timing and time perception has witnessed tremendous growth and multidisciplinary interest in the recent years with the advent of modern neuroimaging and neurophysiological approaches. In this article, I used a data mining approach to analyze the timing literature published by a select group of researchers (n = 202) during the period 2000–2015 and highlight important reviews as well as empirical articles that meet the criterion of a minimum of 100 citations. The qualifying articles (n = 150) are listed in a table along with key details such as number of citations, names of authors, year and journal of publication as well as a short summary of the findings of each study. The results of such a data-driven approach to literature review not only serve as a useful resource to any researcher interested in timing, but also provides a means to evaluate key papers that have significantly influenced the field and summarize recent progress and popular research trends in the field. Additionally, such analyses provides food for thought about future scientific directions and raises important questions about improving organizational structures to boost open science and progress in the field. I discuss exciting avenues for future research that have the potential to significantly advance our understanding of the neurobiology of timing, and propose the establishment of a new society, the Timing Research Forum, to promote open science and collaborative work within the highly diverse and multidisciplinary community of researchers in the field of timing and time perception. PMID:27471445

  13. Trends and structural shifts in health tourism: evidence from seasonal time-series data on health-related travel spending by Canada during 1970-2010.

    Science.gov (United States)

    Loh, Chung-Ping A

    2015-05-01

    There has been a growing interest in better understanding the trends and determinants of health tourism activities. While much of the expanding literature on health tourism offers theoretical or qualitative discussion, empirical evidences has been lacking. This study employs Canada's outbound health tourism activities as an example to examine the trends in health tourism and its association with changing domestic health care market characteristics. A time-series model that accounts for potential structural changes in the trend is employed to analyze the quarterly health-related travel spending series reported in the Balance of Payments Statistics (BOPS) during 1970-2010 (n = 156). We identified a structural shift point which marks the start of an accelerated growth of health tourism and a flattened seasonality in such activities. We found that the health tourism activities of Canadian consumers increase when the private investment in medical facilities declines or when the private MPI increases during the years following the structural-change. We discussed the possible linkage of the structural shift to the General Agreement on Trade in Services (GATS), which went into effect in January, 1995. PMID:25818378

  14. Time Trends and Predictors of Abnormal Postoperative Body Temperature in Infants Transported to the Intensive Care Unit

    Directory of Open Access Journals (Sweden)

    Hedwig Schroeck

    2016-01-01

    Full Text Available Background. Despite increasing adoption of active warming methods over the recent years, little is known about the effectiveness of these interventions on the occurrence of abnormal postoperative temperatures in sick infants. Methods. Preoperative and postoperative temperature readings, patient characteristics, and procedural factors of critically ill infants at a single institution were retrieved retrospectively from June 2006 until May 2014. The primary endpoints were the incidence and trend of postoperative hypothermia and hyperthermia on arrival at the intensive care units. Univariate and adjusted analyses were performed to identify factors independently associated with abnormal postoperative temperatures. Results. 2,350 cases were included. 82% were normothermic postoperatively, while hypothermia and hyperthermia each occurred in 9% of cases. During the study period, hypothermia decreased from 24% to 2% (p<0.0001 while hyperthermia remained unchanged (13% in 2006, 8% in 2014, p=0.357. Factors independently associated with hypothermia were higher ASA status (p=0.02, lack of intraoperative convective warming (p<0.001 and procedure date before 2010 (p<0.001. Independent associations for postoperative hyperthermia included lower body weight (p=0.01 and procedure date before 2010 (p<0.001. Conclusions. We report an increase in postoperative normothermia rates in critically ill infants from 2006 until 2014. Careful monitoring to avoid overcorrection and hyperthermia is recommended.

  15. Research of Manufacture Time Management System Based on PLM

    Science.gov (United States)

    Jing, Ni; Juan, Zhu; Liangwei, Zhong

    This system is targeted by enterprises manufacturing machine shop, analyzes their business needs and builds the plant management information system of Manufacture time and Manufacture time information management. for manufacturing process Combined with WEB technology, based on EXCEL VBA development of methods, constructs a hybrid model based on PLM workshop Manufacture time management information system framework, discusses the functionality of the system architecture, database structure.

  16. A National Picture of Part-Time Community College Faculty: Changing Trends in Demographics and Employment Characteristics

    Science.gov (United States)

    Eagan, Kevin

    2007-01-01

    Although part-time faculty continue to dominate the instructional workforce of community colleges, relatively little is known about this diverse group of individuals. Part-timers are often portrayed as being "free-way flyers" who constantly seek full-time appointments in postsecondary education institutions. However, as this article demonstrates,…

  17. Mapping Clearances in Tropical Dry Forests Using Breakpoints, Trend, and Seasonal Components from MODIS Time Series: Does Forest Type Matter?

    NARCIS (Netherlands)

    Grogan, Kenneth; Pflugmacher, Dirk; Hostert, Patrick; Verbesselt, Jan; Fensholt, Rasmus

    2016-01-01

    Tropical environments present a unique challenge for optical time series analysis, primarily owing to fragmented data availability, persistent cloud cover and atmospheric aerosols. Additionally, little is known of whether the performance of time series change detection is affected by diverse forest

  18. Consequences of Base Time for Redundant Signals Experiments

    OpenAIRE

    Townsend, James T.; Honey, Christopher

    2007-01-01

    We report analytical and computational investigations into the effects of base time on the diagnosticity of two popular theoretical tools in the redundant signals literature: (1) the race model inequality and (2) the capacity coefficient. We show analytically and without distributional assumptions that the presence of base time decreases the sensitivity of both of these measures to model violations. We further use simulations to investigate the statistical power model selection tools based on...

  19. Trends in Protein-Based Biosensor Assemblies for Drug Screening and Pharmaceutical Kinetic Studies

    Directory of Open Access Journals (Sweden)

    Ana M. Gonçalves

    2014-08-01

    Full Text Available The selection of natural and chemical compounds for potential applications in new pharmaceutical formulations constitutes a time-consuming procedure in drug screening. To overcome this issue, new devices called biosensors, have already demonstrated their versatility and capacity for routine clinical diagnosis. Designed to perform analytical analysis for the detection of a particular analyte, biosensors based on the coupling of proteins to amperometric and optical devices have shown the appropriate selectivity, sensibility and accuracy. During the last years, the exponential demand for pharmacokinetic studies in the early phases of drug development, along with the need of lower molecular weight detection, have led to new biosensor structure materials with innovative immobilization strategies. The result has been the development of smaller, more reproducible biosensors with lower detection limits, and with a drastic reduction in the required sample volumes. Therefore in order to describe the main achievements in biosensor fields, the present review has the main aim of summarizing the essential strategies used to generate these specific devices, that can provide, under physiological conditions, a credible molecule profile and assess specific pharmacokinetic parameters.

  20. Deformation Trend Extraction Based on Multi-Temporal InSAR in Shanghai

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2013-04-01

    Full Text Available Shanghai is a modern metropolis characterized by high urban density and anthropogenic ground motions. Although traditional deformation monitoring methods, such as GPS and spirit leveling, are reliable to millimeter accuracy, the sparse point subsidence information makes understanding large areas difficult. Multiple temporal space-borne synthetic aperture radar interferometry is a powerful high-accuracy (sub-millimeter remote sensing tool for monitoring slow ground deformation for a large area with a high point density. In this paper, the Interferometric Point Target Time Series Analysis method is used to extract ground subsidence rates in Shanghai based on 31 C-Band and 35 X-Band synthetic aperture radar (SAR images obtained by Envisat and COSMO SkyMed (CSK satellites from 2007 to 2010. A significant subsidence funnel that was detected is located in the junction place between the Yangpu and the Hongkou Districts. A t-test is formulated to judge the agreements between the subsidence results obtained by SAR and by spirit leveling. In addition, four profile lines crossing the subsidence funnel area are chosen for a comparison of ground subsidence rates, which were obtained by the two different band SAR images, and show a good agreement.

  1. A citation-based analysis and review of significant papers on timing and time perception.

    Directory of Open Access Journals (Sweden)

    Sundeep Teki

    2016-07-01

    Full Text Available Time is an important dimension of brain function, but little is yet known about the underlying cognitive principles and neurobiological mechanisms. The field of timing and time perception has witnessed tremendous growth and multidisciplinary interest in the recent years with the advent of modern neuroimaging and neurophysiological approaches. In this article, I used a data mining approach to analyze the timing literature published by a select group of researchers (n = 202 during the period 2000-2015 and highlight important reviews as well as empirical articles that meet the criterion of a minimum of 100 citations. The qualifying articles (n = 150 are listed in a table along with key details such as number of citations, names of authors, year and journal of publication as well as a short summary of the findings of each study. The results of such a data-driven approach to literature review not only serve as a useful resource to any researcher interested in timing, but also provides a means to evaluate key papers that have significantly influenced the field and summarize recent progress and popular research trends in the field. Additionally, such analyses provides food for thought about future scientific directions and raises important questions about improving organizational structures to boost open science and progress in the field. I discuss exciting avenues for future research that have the potential to significantly advance our understanding of the neurobiology of timing, and propose the establishment of a new society to promote open science and collaborative work within the highly diverse and multidisciplinary community of researchers in the field of timing and time perception.

  2. European drought climatologies and trends based on a multi-indicator approach

    Science.gov (United States)

    Spinoni, Jonathan; Naumann, Gustavo; Vogt, Jürgen; Barbosa, Paulo

    2015-04-01

    Drought is one of the most important weather-induced phenomena which may have severe impacts on different areas such as agriculture, economy, energy production, and society. From a meteorological point of view, drought can be induced and/or reinforced by lack of precipitation, hot temperatures and enhanced evapotranspiration. Starting from a multi-indicator approach, we present European-wide meteorological drought climatologies and trends for the period 1950-2012. As input data, we used precipitation and temperature data from the E-OBS (spatial resolution: 0.25° × 0.25°) gridded dataset of the European Climate Assessment and Dataset (ECA&D). Precipitation, temperature, and the derived potential evapotranspiration (PET) have been used to compute three drought indicators: the Standardized Precipitation Index (SPI), the Standardized Precipitation Evapotranspiration Index (SPEI), and the Reconnaissance Drought Index (RDI). SPI, SPEI, and RDI, calculated for 12-month accumulation period, have been rationally merged into a combined indicator and this quantity has been used to obtain drought frequency, duration, and severity for the entire Europe. We identified the following drought hotspots: Scandinavia, Eastern Europe, and Russia in 1951-1970, no particular hotspot in 1971-1990, the Mediterranean region and the Baltic Republics in 1991-2010. A linear trend analysis shows that drought variables increased in the period 1950-2012 in South-Western Europe, in particular in the Mediterranean and Carpathian regions, with precipitation decrease and PET increase as drivers. Drought variables show a decrease in Scandinavia, Belarus, Ukraine and Russia: precipitation increase is the main driver. In Central Europe and the Balkans, drought variables show a moderate increase, for the significant PET increase outbalances a not significant precipitation increase.

  3. Neural Network Based Finite-Time Stabilization for Discrete-Time Markov Jump Nonlinear Systems with Time Delays

    Directory of Open Access Journals (Sweden)

    Fei Chen

    2013-01-01

    Full Text Available This paper deals with the finite-time stabilization problem for discrete-time Markov jump nonlinear systems with time delays and norm-bounded exogenous disturbance. The nonlinearities in different jump modes are parameterized by neural networks. Subsequently, a linear difference inclusion state space representation for a class of neural networks is established. Based on this, sufficient conditions are derived in terms of linear matrix inequalities to guarantee stochastic finite-time boundedness and stochastic finite-time stabilization of the closed-loop system. A numerical example is illustrated to verify the efficiency of the proposed technique.

  4. On timing properties of LYSO-based calorimeters

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Apresyan, A. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Bornheim, A. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Duarte, J. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Pena, C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Ronzhin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Spiropulu, M. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Trevor, J. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Xie, S. [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2015-04-23

    We present test beam studies and results on the timing performance and characterization of the time resolution of Lutetium–Yttrium Orthosilicate (LYSO)-based calorimeters. We also demonstrate that a time resolution of 30 ps is achievable for a particular design. Additionally, we discuss precision timing calorimetry as a tool for the mitigation of physics object performance degradation effects due to the large number of simultaneous interactions in the high luminosity environment foreseen at the Large Hadron Collider.

  5. On timing properties of LYSO-based calorimeters

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.; Apresyan, A.; Bornheim, A.; Duarte, J.; Pena, C. [California Institute of Technology, Pasadena, CA (United States); Ronzhin, A. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Spiropulu, M., E-mail: smaria@caltech.edu [California Institute of Technology, Pasadena, CA (United States); Trevor, J.; Xie, S. [California Institute of Technology, Pasadena, CA (United States)

    2015-09-11

    We present test beam studies and results on the timing performance and characterization of the time resolution of Lutetium–Yttrium Orthosilicate (LYSO)-based calorimeters. We demonstrate that a time resolution of 30 ps is achievable for a particular design. Furthermore, we discuss precision timing calorimetry as a tool for the mitigation of physics object performance degradation effects due to the large number of simultaneous interactions in the high luminosity environment foreseen at the Large Hadron Collider.

  6. A fast density-based clustering algorithm for real-time Internet of Things stream.

    Science.gov (United States)

    Amini, Amineh; Saboohi, Hadi; Wah, Teh Ying; Herawan, Tutut

    2014-01-01

    Data streams are continuously generated over time from Internet of Things (IoT) devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets.

  7. A Fast Density-Based Clustering Algorithm for Real-Time Internet of Things Stream

    Directory of Open Access Journals (Sweden)

    Amineh Amini

    2014-01-01

    Full Text Available Data streams are continuously generated over time from Internet of Things (IoT devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets.

  8. Detecting cognizable trends of gene expression in a time series RNA-sequencing experiment: a bootstrap approach

    Indian Academy of Sciences (India)

    SHATAKSHEE CHATTERJEE; PARTHA P. MAJUMDER; PRIYANKA PANDEY

    2016-09-01

    Study of temporal trajectory of gene expression is important. RNA sequencing is popular in genome-scale studies of transcription. Because of high expenses involved, many time-course RNA sequencing studies are challenged by inadequacy of sample sizes. This poses difficulties in conducting formal statistical tests of significance of null hypotheses. We propose a bootstrap algorithm to identify ‘cognizable’ ‘time-trends’ of gene expression. Properties of the proposed algorithm are derived using a simulation study. The proposed algorithm captured known ‘time-trends’ in the simulated data with a high probability of success, even when sample sizes were small (n<10). The proposed statistical method is efficient and robust to capture ‘cognizable’ ‘time-trends’ in RNA sequencing data.

  9. Time trends for risk of severe age-related diseases in individuals with and without HIV infection in Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Line D; May, Margaret T; Kronborg, Gitte;

    2015-01-01

    , and were living in Denmark at the time of study inclusion. Data for study outcomes were obtained from the Danish National Hospital Registry and the Danish National Registry of Causes of Death and were cardiovascular diseases (myocardial infarction and stroke), cancers (virus associated, smoking related......, and other), severe neurocognitive disease, chronic kidney disease, chronic liver disease, and osteoporotic fractures. We calculated excess and age-standardised incidence rates and adjusted incidence rate ratios of outcomes for time after HIV diagnosis, highly active antiretroviral therapy (ART) initiation...... of cardiovascular diseases, cancers, and severe neurocognitive disease did not increase substantially with time after HIV diagnosis or ART initiation. Except for chronic kidney diseases, the age-standardised and relative risks of age-related diseases did not increase with calendar time. INTERPRETATIONS: Severe age...

  10. Trends in One-Year Outcomes of Dialysis-Requiring Acute Kidney Injury in Denmark 2005-2012: A Population-Based Nationwide Study

    Science.gov (United States)

    Carlson, Nicholas; Hommel, Kristine; Olesen, Jonas Bjerring; Soja, Anne-Merete; Vilsbøll, Tina; Kamper, Anne-Lise; Torp-Pedersen, Christian; Gislason, Gunnar

    2016-01-01

    Background Dialysis-requiring acute kidney injury (AKI) is associated with substantial mortality and risk of end-stage renal disease (ESRD). Despite considerable growth in incidence of severe AKI, information pertaining to trends in outcomes remains limited. We evaluated time trends in one year risks of ESRD and death in patients with dialysis-requiring AKI over an eight year period in Denmark. Methods In a retrospective nationwide study based on national registers, all adults requiring acute renal replacement therapy between 2005 and 2012 were identified. Patients with preceding ESRD were excluded. Through individual-level cross-referencing of administrative registries, information pertaining to comorbidity, preceding surgical interventions, and concurrent other organ failure and sepsis was ascertained. Comparisons of period-specific one year odds ratios for ESRD and death were calculated in a multiple logistic regression model. Results A total of 13,819 patients with dialysis-requiring AKI were included in the study. Within one year, 1,017 (7.4%) patients were registered with ESRD, and 7,908 (57.2%) patients died. The one-year rate of ESRD decreased from 9.0% between 2005 and 2006 to 6.1% between 2011 and 2012. Simultaneously, the one-year mortality rate decreased from 58.2% between 2005 and 2006 to 57.5% between 2011 and 2012. Consequently, the adjusted odds ratios for the period 2011–2012 (with the period 2005–2006 as reference) were 0.75 (0.60–0.95, p = 0.015) and 0.87 (95% CI 0.78–0.97, p = 0.010) for ESRD and death, respectively. Conclusions In a nationwide retrospective study on time trends in one year outcomes following dialysis-requiring AKI, risk of all-cause mortality and ESRD decreased over a period of 8 years. PMID:27459297

  11. Trend Analysis of Enterprise Internet Public Opinion Based on Microblog%基于微博的企业网络舆情热度趋势分析

    Institute of Scientific and Technical Information of China (English)

    屈启兴; 齐佳音

    2014-01-01

    微博作为企业网络舆情传播的主要载体和平台,使信息传播更迅速,也使舆情事件的影响力剧增。提出基于微博的企业网络舆情热度的计算公式。针对企业网络舆情热度的波动范围较大,并会呈现某种趋势的特点,提出了一种基于马尔可夫链的舆情热度趋势分析模型。该模型采集相关舆情的指标数据,得到热度的时间序列值;划分舆情热度趋势的状态空间;构建状态转移矩阵;预测热度的趋势变化区间。实验表明,该方法能有效地预测企业网络舆情的走势,进而为企业进行网络舆情管理和网络危机公关活动,以及管理效果评估提供理论依据。%Enterprise Internet public opinion often has a hidden trend behind its characteristics shown online. A Markov chain-based Inter-net public opinion analysis method is proposed. We collect microblog data about enterprise Internet public opinion to get the value of time series for the trend. Then the trend changes and the state spaces are analyzed, and the state transition matrix for the final trend is built. Ex-periments demonstrate that this method can effectively predict the trend of enterprise Internet public opinion, and is significant for the enter-prise to guide and controll its Internet public opinion.

  12. A unified model of time perception accounts for duration-based and beat-based timing mechanisms

    Directory of Open Access Journals (Sweden)

    Sundeep eTeki

    2012-01-01

    Full Text Available Accurate timing is an integral aspect of sensory and motor processes such as the perception of speech and music and the execution of skilled movement. Neuropsychological studies of time perception in patient groups and functional neuroimaging studies of timing in normal participants suggest common neural substrates for perceptual and motor timing. A timing system is implicated in core regions of the motor network such as the cerebellum, inferior olive, basal ganglia, pre-supplementary and supplementary motor area, pre-motor cortex and higher regions such as the prefrontal cortex.In this article, we assess how distinct parts of the timing system subserve different aspects of perceptual timing. We previously established brain bases for absolute, duration-based timing and relative, beat-based timing in the olivocerebellar and striato-thalamo-cortical circuits respectively (Teki et al., 2011. However, neurophysiological and neuroanatomical studies provide a basis to suggest that timing functions of these circuits may not be independent.Here, we propose a unified model of time perception based on coordinated activity in the core striatal and olivocerebellar networks that are interconnected with each other and the cerebral cortex th

  13. Finite-time synchronization for memristor-based neural networks with time-varying delays.

    Science.gov (United States)

    Abdurahman, Abdujelil; Jiang, Haijun; Teng, Zhidong

    2015-09-01

    Memristive network exhibits state-dependent switching behaviors due to the physical properties of memristor, which is an ideal tool to mimic the functionalities of the human brain. In this paper, finite-time synchronization is considered for a class of memristor-based neural networks with time-varying delays. Based on the theory of differential equations with discontinuous right-hand side, several new sufficient conditions ensuring the finite-time synchronization of memristor-based chaotic neural networks are obtained by using analysis technique, finite time stability theorem and adding a suitable feedback controller. Besides, the upper bounds of the settling time of synchronization are estimated. Finally, a numerical example is given to show the effectiveness and feasibility of the obtained results. PMID:26024807

  14. Bipolar square-wave current source for transient electromagnetic systems based on constant shutdown time

    Science.gov (United States)

    Wang, Shilong; Yin, Changchun; Lin, Jun; Yang, Yu; Hu, Xueyan

    2016-03-01

    Cooperative work of multiple magnetic transmitting sources is a new trend in the development of transient electromagnetic system. The key is the bipolar current waves shutdown, concurrently in the inductive load. In the past, it was difficult to use the constant clamping voltage technique to realize the synchronized shutdown of currents with different peak values. Based on clamping voltage technique, we introduce a new controlling method with constant shutdown time. We use the rising time to control shutdown time and use low voltage power source to control peak current. From the viewpoint of the circuit energy loss, by taking the high-voltage capacitor bypass resistance and the capacitor of the passive snubber circuit into account, we establish the relationship between the rising time and the shutdown time. Since the switch is not ideal, we propose a new method to test the shutdown time by the low voltage, the high voltage and the peak current. Experimental results show that adjustment of the current rising time can precisely control the value of the clamp voltage. When the rising time is fixed, the shutdown time is unchanged. The error for shutdown time deduced from the energy consumption is less than 6%. The new controlling method on current shutdown proposed in this paper can be used in the cooperative work of borehole and ground transmitting system.

  15. PM trend study for the 1998 - 2012 period: Impact of Transport and Petroleum-based Fuels in Santiago Chile

    Science.gov (United States)

    Castillo, M. A.; Jhun, I.; Moreno, F.; Oyola, P.; Koutrakis, P.

    2013-05-01

    Santiago is the capital city of Chile and the combination of adverse climatic and geographical conditions, a continuously growing vehicle fleet, and an increasing number of industries, has made Santiago one of the most polluted cities in South America, and has been declared saturated zone for PM10 since 1996. Although there have been important reductions in the PM emissions due the implementation of the "Atmospheric Prevention and Decontamination Plan for the Metropolitan Region" (PPDA) however the efforts have not been enough to meet the actual standards. Currently is approved a standard for PM2.5, where the annual average is 20 μg/m3 and daily average 24 hr is 50 μg/m3. One of the PM2.5 sources are the traffic emission and one of the measures targeted in PPDA has been to regulate this source. In the last 20 years two of the main interventions have been the elimination of Lead in gasoline (2001) and the steadily reduced diesel sulfur content from 5,000 to 50 ppm. In this study we analyzed 14 years of PM2.5 mass and species concentration time's series, from April 1998 to August 2012, elemental chemical analysis was made for approximately 60% of samples using XRF technique at DRI Lab (USA). One of the objectives is evaluate the impact of fuel-related interventions and petroleum-based fuels (PBFs) sales. When was analyzed de lead concentration we found that is present in the environment despite of that was eliminated of gasoline 20 years ago. We analyzed the impact of diesel sulfur on ambient sulfur content, and was constructed a model to verify the relationship between ambient sulfur and diesel sulfur content after controlling for other covariates. The relation between ambient concentration and diesel content sulfur is linear, when the reduction of sulfur in diesel was from 1500 to 50 ppm the concentration decreased from 1.59 to 1.08 μg/m3. To determinate the impact of PBFs sales (gasoline, kerosene, petroleum) on PM2.5 concentration, we estimated PM2

  16. Variability and Trends in the Global Water Cycle Based on Multi-Decadal Earth Science Data Record

    Science.gov (United States)

    Wood, E. F.; Coccia, G.; Pan, M.; Sheffield, J.

    2014-12-01

    Documentation of the global water cycle and its evolution over time has been a primary scientific goal of the Global Energy and Water Exchanges Project, and is fundamental to providing a benchmark for the present climate, to document inter-annual variability and global change impacts, and to validate models. In developed countries, observation systems that include in-situ, remote sensing and modeled data can provide long-term, consistent and generally high quality datasets of water cycle variables. In less developed, data sparse regions, in situ data alone are insufficient to develop a comprehensive picture of how the water cycle is changing, and strategies that merge in-situ, model and satellite observations within a framework that results in consistent water cycle records is essential. This presentation will utilize newly developed, multi-decadal water and energy cycles data sets to analyze and advance our understanding of the role of the terrestrial hydrosphere in Earth's climate system. The data sets include a 60-year global water cycle dataset developed through a NASA-sponsored multi-institutional effort under the NASA MEaSUREs program, multi-model terrestrial evapotranspiration data sets coordinated under the GEWEX Data and Assessments Panel (GDAP) as part of the LandFlux initiative, and ocean evaporation under SeaFlux. The foundations of the datasets are a variety of independent large-scale datasets of the hydrologic variables that are used to bridge the gap between sparse in-situ observations, including remote-sensing based retrievals, observation-forced hydrologic modeling, and weather model reanalyses. Analyses are carried out across a range of temporal and spatial scales from monthly to annual and decadal, and from ~250 river basins to continental and global scales, and will address long-standing GEWEX science questions that include (i) quantifying the nature and extent of changes (trends and variability) to the terrestrial hydrosphere over the last 60

  17. Parametric adaptive time-frequency representation based on time-sheared Gabor atoms

    Institute of Scientific and Technical Information of China (English)

    Ma Shiwei; Zhu Xiaojin; Chen Guanghua; Wang Jian; Cao Jialin

    2007-01-01

    A localized parametric time-sheared Gabor atom is derived by convolving a linear frequency modulated factor, modulating in frequency and translating in time to a dilated Gaussian function, which is the generalization of Gabor atom and is more delicate for matching most of the signals encountered in practice, especially for those having frequency dispersion characteristics. The time-frequency distribution of this atom concentrates in its time center and frequency center along energy curve, with the curve being oblique to a certain extent along the time axis. A novel parametric adaptive time-frequency distribution based on a set of the derived atoms is then proposed using a adaptive signal subspace decomposition method in frequency domain, which is non-negative time-frequency energy distribution and free of cross-term interference for multicomponent signals. The results of numerical simulation manifest the effectiveness of the approach in time-frequency representation and signal de-noising processing.

  18. X-Ray Pulsar Based Navigation and Time Determination Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm will build on the Phase I X-ray pulsar-based navigation and timing (XNAV) feasibility assessment to develop a detailed XNAV simulation capability to...

  19. Real-time holography on bacteriorhodopsin-based materials

    Science.gov (United States)

    Taranenko, Victor B.

    1998-09-01

    The main properties and mechanisms of photoresponse of the bacteriohodopsin-based materials are presented. Fields of their potential applications in the real-time holography and nonlinear optics are discussed.

  20. THE TREND OF MALARIA IN GOA (INDIA: RETROSPECTIVE RECORD BASED STUDY

    Directory of Open Access Journals (Sweden)

    Rahul

    2015-10-01

    Full Text Available BACKGROUND: Malaria is one of the most widespread and fatal vector borne diseases found in India. The high level of morbidity and mortality associated with this disease makes it a disease of public health importance. Goa is known endemic area for malaria and has witne ssed many outbreaks of malaria in recent past with increased levels of mortality. The National Vector Borne Diseases Control Programme (NVBDCP is operational in the State and the country since many years. The current study is aimed at reviewing the achiev ements under this programme in Goa. MATERIALS AND METHODS : The study is based on the retrospective data of malaria cases diagnosed and treated at the all Health Care Units located in different parts of Goa. This data is generated at each Health Care Unit w hich is forwarded to NVBDCP every day for compilation. The data on the malaria cases and deaths due to malaria over last six years (2006 to 2011 was analyzed for the study. RESULTS: Goa witnessed a sudden rise in incidence of malaria cases from 3.55 per 1 000 population in 2006 to 6.82 in 2007. With the aggressive implementation of control measures by NVBDCP and all health care units the incidence of malaria was brought under control from 6.79 per 1000 in 2008 to 0.67 per 1000 in 2011. The proportion of pl. falciparum is also kept under control (25.43%. Study shows that adult male ( M ale: female ratio 5:1 population is affected more as compared to children and female population. The migrant labor community is proportionately more infested (S ix times more at risk by malaria as compared to local native residents. A high proportion of cases are reported from Urban Health Care units indicating that Goa has more urban clustering of cases. CONCULSION: The burden of Malaria disease is fortunately on declining tren d in Goa over the last six years. The prominent contributing factors which have helped in the interruption of malaria transmission are : 1 Increased level public awareness

  1. Adaptive Fourier Decomposition Based Time-Frequency Analysis

    Institute of Scientific and Technical Information of China (English)

    Li-Ming Zhang

    2014-01-01

    The attempt to represent a signal simultaneously in time and frequency domains is full of challenges. The recently proposed adaptive Fourier decomposition (AFD) offers a practical approach to solve this problem. This paper presents the principles of the AFD based time-frequency analysis in three aspects: instantaneous frequency analysis, frequency spectrum analysis, and the spectrogram analysis. An experiment is conducted and compared with the Fourier transform in convergence rate and short-time Fourier transform in time-frequency distribution. The proposed approach performs better than both the Fourier transform and short-time Fourier transform.

  2. New software rejuvenation strategy based on measurement and time

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Operational software systems often experience an "aging" phenomenon, characterized by progressive performance degradation and a sudden hang/crash failure. Software rejuvenation is a proactive fault-tolerance strategy aimed to prevent unexpected outages due to aging. A new rejuvenation strategy based on measurement and time, and constructs a SRN model to evaluate this strategy. Numerical results show that this strategy outweighs either the purely measurementbased or the purely time-based strategy and can effectively improve system performance.

  3. Virtual Space Communication based on Real-time Human Proxy

    OpenAIRE

    Arita, Daisaku; Yoshimatsu, Hisato; Hayama, Daisuke; Taniguchi, Rin-ichiro

    2004-01-01

    In this paper, we propose a concept of real-time human proxy for avatar-based interaction systems, which virtualizes a human in the real world in real-time and which lets the virtualized human behave as if he/she was present at a distant place. For estimating RHP, we apply it to VEIDL, which is a virtual classroom system. The experimental results show us that RHP is useful for avatar-based interaction.

  4. Homonegativity among first and second generation migrants in Europe: the interplay of time trends, origin, destination and religion.

    Science.gov (United States)

    Van der Bracht, Koen; Van de Putte, Bart

    2014-11-01

    Previous studies reported declining disapproval of homosexuality in Europe but have simultaneously identified the decelerating effect of religiosity and the higher disapproval of homosexuality among migrants. In this paper, we address disapproval of homosexuality among first- and second-generation migrants in Europe by assessing (1) period and cohort changes, (2) origin and destination country influences and (3) the role of religiosity. We develop a specific cross-classified multilevel design enabling us to simultaneously examine these influences. We test hypotheses using a subsample of the European Social Survey (ESS), containing 19,878 first and second generation migrants. The analyses lead to three important conclusions. Firstly, disapproval of homosexuality is declining both over time and across cohorts. Secondly, migrants conform to levels of disapproval of homosexuality among natives in the destination country, and this explains the decline among migrants over time. Thirdly, religion has a multi-faceted influence on levels of disapproval of homosexuality among migrants. PMID:25131278

  5. RETRIEVAL TIME RESEARCH IN TEMPORAL KNOWLEDGE BASES WITH DYNAMIC CONTENT

    Directory of Open Access Journals (Sweden)

    J. A. Koroleva

    2015-07-01

    Full Text Available Results of retrieval time research of actual data effectiveness search in temporal knowledge bases built in the basis of state of events have been proposed. This type of knowledge base gives the possibility for quick access to relevant states as well as for history based on events chronology. It is shown that data storage for deep retrospective increases significantly the search time due to the growth of the decision tree. The search time for temporal knowledge bases depending on the average number of events prior to the current state has been investigated. Experimental results confirm the advantage of knowledge bases in the basis of state of events over traditional methods for design of intelligent systems.

  6. UML statechart based rigorous modeling of real-time system

    Institute of Scientific and Technical Information of China (English)

    LAI Ming-zhi; YOU Jin-yuan

    2005-01-01

    Rigorous modeling could ensure correctness and could verify a reduced cost in embedded real-time system development for models. Software methods are needed for rigorous modeling of embedded real-time systems. PVS is a formal method with precise syntax and semantics defined. System modeled by PVS specification could be verified by tools. Combining the widely used UML with PVS, this paper provides a novel modeling and verification approach for embedded real-time systems. In this approach, we provide 1 ) a time-extended UML statechart for modeling dynamic behavior of an embedded real-time system; 2) an approach to capture timed automata based semantics from a timed statechart; and 3) an algorithm to generate a finite state model expressed in PVS specification for model checking. The benefits of our approach include flexibility and user friendliness in modeling, extendability in formalization and verification content, and better performance. Time constraints are modeled and verified and is a highlight of this paper.

  7. The Effects of Leisure-Based Screen Time

    Science.gov (United States)

    Meier, Mary Dawn; Hager, Ronald L.; Vincent, Susan D.; Tucker, Larry A.; Vincent, William J.

    2007-01-01

    Background: Use of television, computers, and video games competes with physical activity and may be a health risk factor. Purpose: This study assessed the relationship between leisure-based screen time and physical activity in families to determine whether assignment to a limited screen time group results in more physical activity. Methods:…

  8. Predictors of Time-Based Prospective Memory in Children

    Science.gov (United States)

    Mackinlay, Rachael J.; Kliegel, Matthias; Mantyla, Timo

    2009-01-01

    This study identified age differences in time-based prospective memory performance in school-aged children and explored possible cognitive correlates of age-related performance. A total of 56 7- to 12-year-olds performed a prospective memory task in which prospective memory accuracy, ongoing task performance, and time monitoring were assessed.…

  9. Time difference based measurement of ultrasonic cavitations in wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    朱昌平

    2016-01-01

    Intensity of cavitation is significant in ultrasonic wastewater treatment, but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.

  10. Finite-time synchronization of fractional-order memristor-based neural networks with time delays.

    Science.gov (United States)

    Velmurugan, G; Rakkiyappan, R; Cao, Jinde

    2016-01-01

    In this paper, we consider the problem of finite-time synchronization of a class of fractional-order memristor-based neural networks (FMNNs) with time delays and investigated it potentially. By using Laplace transform, the generalized Gronwall's inequality, Mittag-Leffler functions and linear feedback control technique, some new sufficient conditions are derived to ensure the finite-time synchronization of addressing FMNNs with fractional order α:1memristor-based neural networks. Finally, three numerical examples are presented to show the effectiveness of our proposed theoretical results. PMID:26547242

  11. PREDICTING THE FINAL TIME IN SLALOM BASED ON THE TIME OF THE FIRST AND SECOND RACE

    OpenAIRE

    Bojan Matković; Mihajlo Mijanović

    2011-01-01

    Prediction of final race time in slalom based on the time achieved in first and second race is a paper with a purpose and a primary goal to address the attention to relevant factors that determine final result in alpine skiing, and all that based on exact indicators gained under exact and strictly con�trolled rules of FIS. The mentioned example is about slalom discipline. Due to the fact that the result is a primary goal, the asked question is: Does the final result depend more on time achiev...

  12. Current trends and age-based differences of unintentional injury in Japanese children.

    Science.gov (United States)

    Yamamoto, Natsuki; Honda, Chikako; Nagata, Satoko

    2016-05-23

    Unintentional injury in children is a worldwide public health problem, as it increases the health burden and is a leading cause of death among children. It is important to understand the differences between different age groups of children in regard to unintentional injury, in order to effectively implement child safety education. The present study aimed to determine the current trends of unintentional injury in children, and to identify the differences between different age groups of children with regard to unintentional injury. We identified 1,521 children who attended an 18-month health checkup (18-month group), and 1,368 children who attended a 36-month health checkup (36-month group), between January 1, 2014 and December 31, 2014. The rate of hospital visits associated with unintentional injury was 10.6% (161/1,521) in the 18-month group, and 13.1% (180/1,368) in the 36-month group. In both groups, present/past illness was associated with hospital visits, and in the 36-month group, hospital visits were more common in boys than in girls. The number of unintentional injuries that occurred outdoors was higher in the 36-month group than in the 18-month group. Unintentional injuries resulting from accidental ingestion and falls were more common in the 18-month group, while unintentional injuries resulting from turning over were more common in the 36-month group. In conclusion, the number of hospital visits for unintentional injury might be higher, and the number of preventive actions taken by mothers might be lower, among children attending the 36-month health checkup than among those attending the 18-month health checkup. PMID:27020119

  13. Estimating trends of population decline in long-lived marine species in the Mediterranean Sea based on fishers' perceptions.

    Science.gov (United States)

    Maynou, Francesc; Sbrana, Mario; Sartor, Paolo; Maravelias, Christos; Kavadas, Stefanos; Damalas, Dimitros; Cartes, Joan E; Osio, Giacomo

    2011-01-01

    We conducted interviews of a representative sample of 106 retired fishers in Italy, Spain and Greece, asking specific questions about the trends they perceived in dolphin and shark abundances between 1940 and 1999 (in three 20 year periods) compared to the present abundance. The large marine fauna studied were not target species of the commercial fleet segment interviewed (trawl fishery). The fishers were asked to rank the perceived abundance in each period into qualitative ordinal classes based on two indicators: frequency of sightings and frequency of catches (incidental or intentional) of each taxonomic group. The statistical analysis of the survey results showed that both incidental catches and the sighting frequency of dolphins have decreased significantly over the 60+ years of the study period (except for in Greece due to the recent population increase). This shows that fishers' perceptions are in agreement with the declining population trends detected by scientists. Shark catches were also perceived to have diminished since the early 1940s for all species. Other long-lived Mediterranean marine fauna (monk seals, whales) were at very low levels in the second half of the 20(th) century and no quantitative data could be obtained. Our study supports the results obtained in the Mediterranean and other seas that show the rapid disappearance (over a few decades) of marine fauna. We show that appropriately designed questionnaires help provide a picture of animal abundance in the past through the valuable perceptions of fishers. This information can be used to complement scientific sources or in some cases be taken as the only information source for establishing population trends in the abundance of sensitive species.

  14. Estimating trends of population decline in long-lived marine species in the Mediterranean Sea based on fishers' perceptions.

    Directory of Open Access Journals (Sweden)

    Francesc Maynou

    Full Text Available We conducted interviews of a representative sample of 106 retired fishers in Italy, Spain and Greece, asking specific questions about the trends they perceived in dolphin and shark abundances between 1940 and 1999 (in three 20 year periods compared to the present abundance. The large marine fauna studied were not target species of the commercial fleet segment interviewed (trawl fishery. The fishers were asked to rank the perceived abundance in each period into qualitative ordinal classes based on two indicators: frequency of sightings and frequency of catches (incidental or intentional of each taxonomic group. The statistical analysis of the survey results showed that both incidental catches and the sighting frequency of dolphins have decreased significantly over the 60+ years of the study period (except for in Greece due to the recent population increase. This shows that fishers' perceptions are in agreement with the declining population trends detected by scientists. Shark catches were also perceived to have diminished since the early 1940s for all species. Other long-lived Mediterranean marine fauna (monk seals, whales were at very low levels in the second half of the 20(th century and no quantitative data could be obtained. Our study supports the results obtained in the Mediterranean and other seas that show the rapid disappearance (over a few decades of marine fauna. We show that appropriately designed questionnaires help provide a picture of animal abundance in the past through the valuable perceptions of fishers. This information can be used to complement scientific sources or in some cases be taken as the only information source for establishing population trends in the abundance of sensitive species.

  15. Varying trends in surface energy fluxes and associated climatebetween 1960-2002 based on transient climate simulations

    Energy Technology Data Exchange (ETDEWEB)

    Nazarenko, Larissa; Menon, Surabi

    2005-07-20

    The observed reduction in land surface radiation over the last several decades (1960-1990)---the so-called ''dimming effect''--- and the more recent evidence of a reversal in ''dimming'' over some locations beyond 1990 suggest several consequences on climate, notably on the hydrological cycle. Such a reduction in radiation should imply reduced surface temperature (Ts) and precipitation, which have not occurred. We have investigated the possible causes for the above climate features using a climate model coupled to a dynamic ocean model under natural and anthropogenic conditions. To isolate the aerosol influence on surface radiation trends, we have analyzed transient climate simulations from1960 to 2002 with and without anthropogenic aerosols. Based on a linear trend with aerosol effects included, the global mean change in the surface solar radiation absorbed over land is -0.021+-0.0033 Wm-2yr-1. Although the overall trend is negative, we do note a reversal in dimming after 1990, consistent with observations. Without aerosol effects, the surface solar radiation absorbed over land increases throughout 1960 to 2002, mainly due to the decrease in cloud cover associated with increased greenhouse warming. In spite of a simulated increase in Ts of 0.012 Kyr-1 for 1960 to 2002, the global mean latent heat flux and associated intensity of the hydrological cycle decrease overall, however with increases over some land locations due mainly to moisture advection. Simulated changes correspond more closely to observed changes when accounting for aerosol effects on climate.

  16. Rectal temperature-based death time estimation in infants.

    Science.gov (United States)

    Igari, Yui; Hosokai, Yoshiyuki; Funayama, Masato

    2016-03-01

    In determining the time of death in infants based on rectal temperature, the same methods used in adults are generally used. However, whether the methods for adults are suitable for infants is unclear. In this study, we examined the following 3 methods in 20 infant death cases: computer simulation of rectal temperature based on the infinite cylinder model (Ohno's method), computer-based double exponential approximation based on Marshall and Hoare's double exponential model with Henssge's parameter determination (Henssge's method), and computer-based collinear approximation based on extrapolation of the rectal temperature curve (collinear approximation). The interval between the last time the infant was seen alive and the time that he/she was found dead was defined as the death time interval and compared with the estimated time of death. In Ohno's method, 7 cases were within the death time interval, and the average deviation in the other 12 cases was approximately 80 min. The results of both Henssge's method and collinear approximation were apparently inferior to the results of Ohno's method. The corrective factor was set within the range of 0.7-1.3 in Henssge's method, and a modified program was newly developed to make it possible to change the corrective factors. Modification A, in which the upper limit of the corrective factor range was set as the maximum value in each body weight, produced the best results: 8 cases were within the death time interval, and the average deviation in the other 12 cases was approximately 80min. There was a possibility that the influence of thermal isolation on the actual infants was stronger than that previously shown by Henssge. We conclude that Ohno's method and Modification A are useful for death time estimation in infants. However, it is important to accept the estimated time of death with certain latitude considering other circumstances.

  17. Long-term hmF2 trends in the Eurasian longitudinal sector from the ground-based ionosonde observations

    Directory of Open Access Journals (Sweden)

    M. Herraiz

    Full Text Available The method earlier used for the foF2 long-term trends analysis is applied to reveal hmF2 long-term trends at 27 ionosonde stations in the European and Asian longitudinal sectors. Observed M(3000F2 data for the last 3 solar cycles are used to derive hmF2 trends. The majority of the studied stations show significant hmF2 linear trends with a confidence level of at least 95% for the period after 1965, with most of these trends being positive. No systematic variation of the trend magnitude with latitude is revealed, but some longitudinal effect does take place. The proposed geomagnetic storm concept to explain hmF2 long-term trends proceeds from a natural origin of the trends rather than an artificial one related to the thermosphere cooling due to the greenhouse effect.Key words. Ionosphere (ionosphere-atmosphere interaction

  18. Real-time collaboration in activity-based architectures

    DEFF Research Database (Denmark)

    Bardram, Jakob Eyvind; Christensen, Henrik Bærbak

    2004-01-01

    With the growing research into mobile and ubiquitous computing, there is a need for addressing how such infrastructures can support collaboration between nomadic users. We present the activity based computing paradigm and outline a proposal for handling collaboration in an activity......-based architecture. We argue that activity-based computing establishes a natural and sound conceptual and architectural basis for session management in real-time, synchronous collaboration....

  19. Image-Based Learning Approach Applied to Time Series Forecasting

    Directory of Open Access Journals (Sweden)

    J. C. Chimal-Eguía

    2012-06-01

    Full Text Available In this paper, a new learning approach based on time-series image information is presented. In order to implementthis new learning technique, a novel time-series input data representation is also defined. This input datarepresentation is based on information obtained by image axis division into boxes. The difference between this newinput data representation and the classical is that this technique is not time-dependent. This new information isimplemented in the new Image-Based Learning Approach (IBLA and by means of a probabilistic mechanism thislearning technique is applied to the interesting problem of time series forecasting. The experimental results indicatethat by using the methodology proposed in this article, it is possible to obtain better results than with the classicaltechniques such as artificial neuronal networks and support vector machines.

  20. Survival trends in metastatic bladder cancer in the United States: A population based study

    Directory of Open Access Journals (Sweden)

    Binay Kumar Shah

    2015-01-01

    Conclusions: This population-based study shows that decreases in 6-month and 12-month relative survival rates among patients with MBC in 2001-2010 compared to 1991-2000, specifically, more pronounced among CC men and Oth men.

  1. Value-Based Marketing: A Dsicussion of Issues and Trends in the Slaughter Cattle Market

    OpenAIRE

    Scott W. Fausti; Diersen, Matthew A.; Qasmi, Bashir A.; Li, Jing

    2009-01-01

    Pricing and technological innovation are discussed within the context of the beef industry’s value-based marketing initiative. Cash and contract marketing practices for fed cattle are addressed with respect to slaughter volume and pricing methods (live, dressed, and grid). A methodology for estimating grid market share of weekly slaughter volume, based on USDA market reports (2004–2009), is introduced. Weekly grid market shares for the cash and contract markets are derived. Summary statis...

  2. Trends in the Marketing Development within the Context of the Knowledge Based Economy

    OpenAIRE

    Valerica Olteanu

    2006-01-01

    Nowadays, human society is passing through a new stage called knowledge based economy. This concept is reflected in a specific way in the marketing theory. We know that marketing, as a science, appeared as an answer to the development of Economy. The Romanian marketing school places at the origins of marketing the social-economic dynamism. From this point of view, we believe that the science of marketing itself an element that explains knowledge based economy. However, with the premises of th...

  3. Audio Effects Based on Biorthogonal Time-Varying Frequency Warping

    Directory of Open Access Journals (Sweden)

    Cavaliere Sergio

    2001-01-01

    Full Text Available We illustrate the mathematical background and musical use of a class of audio effects based on frequency warping. These effects alter the frequency content of a signal via spectral mapping. They can be implemented in dispersive tapped delay lines based on a chain of all-pass filters. In a homogeneous line with first-order all-pass sections, the signal formed by the output samples at a given time is related to the input via the Laguerre transform. However, most musical signals require a time-varying frequency modification in order to be properly processed. Vibrato in musical instruments or voice intonation in the case of vocal sounds may be modeled as small and slow pitch variations. Simulation of these effects requires techniques for time-varying pitch and/or brightness modification that are very useful for sound processing. The basis for time-varying frequency warping is a time-varying version of the Laguerre transformation. The corresponding implementation structure is obtained as a dispersive tapped delay line, where each of the frequency dependent delay element has its own phase response. Thus, time-varying warping results in a space-varying, inhomogeneous, propagation structure. We show that time-varying frequency warping is associated to an expansion over biorthogonal sets generalizing the discrete Laguerre basis. Slow time-varying characteristics lead to slowly varying parameter sequences. The corresponding sound transformation does not suffer from discontinuities typical of delay lines based on unit delays.

  4. Audio Effects Based on Biorthogonal Time-Varying Frequency Warping

    Science.gov (United States)

    Evangelista, Gianpaolo; Cavaliere, Sergio

    2001-12-01

    We illustrate the mathematical background and musical use of a class of audio effects based on frequency warping. These effects alter the frequency content of a signal via spectral mapping. They can be implemented in dispersive tapped delay lines based on a chain of all-pass filters. In a homogeneous line with first-order all-pass sections, the signal formed by the output samples at a given time is related to the input via the Laguerre transform. However, most musical signals require a time-varying frequency modification in order to be properly processed. Vibrato in musical instruments or voice intonation in the case of vocal sounds may be modeled as small and slow pitch variations. Simulation of these effects requires techniques for time-varying pitch and/or brightness modification that are very useful for sound processing. The basis for time-varying frequency warping is a time-varying version of the Laguerre transformation. The corresponding implementation structure is obtained as a dispersive tapped delay line, where each of the frequency dependent delay element has its own phase response. Thus, time-varying warping results in a space-varying, inhomogeneous, propagation structure. We show that time-varying frequency warping is associated to an expansion over biorthogonal sets generalizing the discrete Laguerre basis. Slow time-varying characteristics lead to slowly varying parameter sequences. The corresponding sound transformation does not suffer from discontinuities typical of delay lines based on unit delays.

  5. Policy trends and reforms in the German DRG-based hospital payment system.

    Science.gov (United States)

    Klein-Hitpaß, Uwe; Scheller-Kreinsen, David

    2015-03-01

    A central structural point in all DRG-based hospital payment systems is the conversion of relative weights into actual payments. In this context policy makers need to address (amongst other things) (a) how the price level of DRG-payments from one period to the following period is changed and (b) whether and how hospital payments based on DRGs are to be differentiated beyond patient characteristics, e.g. by organizational, regional or state-level factors. Both policy problems can be and in international comparison often are empirically addressed. In Germany relative weights are derived from a highly sophisticated empirical cost calculation, whereas the annual changes of DRG-based payments (base rates) as well as the differentiation of DRG-based hospital payments beyond patient characteristics are not empirically addressed. Rather a complex set of regulations and quasi-market negotiations are applied. There were over the last decade also timid attempts to foster the use of empirical data to address these points. However, these reforms failed to increase the fairness, transparency and rationality of the mechanism to convert relative weights into actual DRG-based hospital payments. PMID:25638648

  6. Magnitude, frequency, and trends of floods at gaged and ungaged sites in Washington, based on data through water year 2014

    Science.gov (United States)

    Mastin, Mark C.; Konrad, Christopher P.; Veilleux, Andrea G.; Tecca, Alison E.

    2016-09-20

    An investigation into the magnitude and frequency of floods in Washington State computed the annual exceedance probability (AEP) statistics for 648 U.S. Geological Survey unregulated streamgages in and near the borders of Washington using the recorded annual peak flows through water year 2014. This is an updated report from a previous report published in 1998 that used annual peak flows through the water year 1996. New in this report, a regional skew coefficient was developed for the Pacific Northwest region that includes areas in Oregon, Washington, Idaho and western Montana within the Columbia River drainage basin south of the United States-Canada border, the coastal areas of Oregon and western Washington, and watersheds draining into Puget Sound, Washington. The skew coefficient is an important term in the Log Pearson Type III equation used to define the distribution of the log-transformed annual peaks. The Expected Moments Algorithm was used to fit historical and censored peak-flow data to the log Pearson Type III distribution. A Multiple Grubb-Beck test was employed to censor low outliers of annual peak flows to improve on the frequency distribution. This investigation also includes a section on observed trends in annual peak flows that showed significant trends (p-value based map tool created by the U.S. Geological Survey to allow the user to choose a streamgage and obtain published statistics or choose ungaged locations where the program automatically applies the regional regression equations and computes the estimates of the AEP statistics.

  7. Influence of two different geo-climatic zones on the prevalence and time trends of asthma symptoms among Spanish adolescents and schoolchildren

    Science.gov (United States)

    García-Marcos, Luis; Batllés-Garrido, José; Blanco-Quirós, Alfredo; García-Hernández, Gloria; Guillén-Grima, Francisco; González-Díaz, Carlos; García-Merino, Águeda; Arnedo-Pena, Alberto; Busquets-Monge, Rosa M.; Morales-Suárez-Varela, María; López-Silvarrey-Varela, Ángel; García-Andoin, Nekane

    2009-01-01

    Few studies have focused on the long-term influence of the climate on the prevalence of asthma. The aim of this study is to establish the influence of geo-climatic conditions on the prevalence of asthma symptoms both in adolescents and schoolchildren, and to discover if this influence is associated with their time trends. Eight centres in Spain performed both ISAAC phases I (1994) and III (2002) in children 13-14 years old. Six of them also surveyed children 6-7 years old. For each age group and phase, about 3,000 children were surveyed per centre. This study examines the prevalence of current wheeze and severe current wheeze in two different geo-climatic zones, coast and plateau, considering their relative humidity and temperature range. In both age groups, the mean asthma prevalence on the coast, for phase I and III, was significantly higher than on the plateau. Living on the plateau was an independent protective factor for current wheeze and severe current wheeze for the two age groups. Within the coastal centres, the increase of the annual relative humidity was a statistical significant risk factor for current wheeze, the same trend existing for current severe wheeze. These effects were independent of the sex and of the phase of the study. The prevalence of asthma and severe asthma symptoms is more frequent on the coast of Spain as compared to the inner plateau. This finding was repeated both in 1994 and in 2002.

  8. A Dynamic Travel Time Estimation Model Based on Connected Vehicles

    Directory of Open Access Journals (Sweden)

    Daxin Tian

    2015-01-01

    Full Text Available With advances in connected vehicle technology, dynamic vehicle route guidance models gradually become indispensable equipment for drivers. Traditional route guidance models are designed to direct a vehicle along the shortest path from the origin to the destination without considering the dynamic traffic information. In this paper a dynamic travel time estimation model is presented which can collect and distribute traffic data based on the connected vehicles. To estimate the real-time travel time more accurately, a road link dynamic dividing algorithm is proposed. The efficiency of the model is confirmed by simulations, and the experiment results prove the effectiveness of the travel time estimation method.

  9. Trends of Sustainable Residential Architecture

    OpenAIRE

    Narvydas, A

    2015-01-01

    The article is based on Master’s research conducted during Scottish Housing Expo 2010. The aim of the research was to determine the prevailing trends in sustainable residential architecture. Each trend can be described by features detected during visual and technical observation of project data. Based on that architects may predict possible problems related to a specific trend.

  10. Analysis and Trend Determination of the Evolution of Tourist Accommodation Establishments (Adjusted Data Based Seasonally in the European Union (28 with Analytical Methods

    Directory of Open Access Journals (Sweden)

    Rodica Pripoaie

    2015-05-01

    Full Text Available This work presents the comparative analysis and trend determination of the evolution tourist accommodation establishments in the European Union (28, adjusted data based seasonally, in the period May 2014 - December 2014 used the Analytical Methods. The principal causes of the evolution tourist accommodation establishments were: the general economic evolution of industries and GDP per capita, the relatively low revenue or low development of the infrastructure. Trend determination of the evolution tourist accommodation establishments in the European Union (28 with analytical methods requires least squares method. On the base the results of the absolute deviations between empirical and theoretical values for the linear, curvilinear and modified exponential regression, will choose the best trend equation for the smallest variation. The best trend model for evolution tourist accommodation establishments in EU (28 is modelled using linear regression equation.

  11. Traffic Incident Clearance Time and Arrival Time Prediction Based on Hazard Models

    Directory of Open Access Journals (Sweden)

    Yang beibei Ji

    2014-01-01

    Full Text Available Accurate prediction of incident duration is not only important information of Traffic Incident Management System, but also an effective input for travel time prediction. In this paper, the hazard based prediction models are developed for both incident clearance time and arrival time. The data are obtained from the Queensland Department of Transport and Main Roads’ STREAMS Incident Management System (SIMS for one year ending in November 2010. The best fitting distributions are drawn for both clearance and arrival time for 3 types of incident: crash, stationary vehicle, and hazard. The results show that Gamma, Log-logistic, and Weibull are the best fit for crash, stationary vehicle, and hazard incident, respectively. The obvious impact factors are given for crash clearance time and arrival time. The quantitative influences for crash and hazard incident are presented for both clearance and arrival. The model accuracy is analyzed at the end.

  12. Why are you late? Investigating the role of time management in time-based prospective memory.

    Science.gov (United States)

    Waldum, Emily R; McDaniel, Mark A

    2016-08-01

    Time-based prospective memory tasks (TBPM) are those that are to be performed at a specific future time. Contrary to typical laboratory TBPM tasks (e.g., hit the Z key every 5 min), many real-world TBPM tasks require more complex time-management processes. For instance, to attend an appointment on time, one must estimate the duration of the drive to the appointment and then use this estimate to create and execute a secondary TBPM intention (e.g., "I need to start driving by 1:30 to make my 2:00 appointment on time"). Future under- and overestimates of drive time can lead to inefficient TBPM performance with the former lending to missed appointments and the latter to long stints in the waiting room. Despite the common occurrence of complex TBPM tasks in everyday life, to date, no studies have investigated how components of time management, including time estimation, affect behavior in such complex TBPM tasks. Therefore, the current study aimed to investigate timing biases in both older and younger adults and, further, to determine how such biases along with additional time management components including planning and plan fidelity influence complex TBPM performance. Results suggest for the first time that younger and older adults do not always utilize similar timing strategies, and as a result, can produce differential timing biases under the exact same environmental conditions. These timing biases, in turn, play a vital role in how efficiently both younger and older adults perform a later TBPM task that requires them to utilize their earlier time estimate. (PsycINFO Database Record PMID:27336325

  13. Time series analysis of temporal trends in the pertussis incidence in Mainland China from 2005 to 2016.

    Science.gov (United States)

    Zeng, Qianglin; Li, Dandan; Huang, Gui; Xia, Jin; Wang, Xiaoming; Zhang, Yamei; Tang, Wanping; Zhou, Hui

    2016-01-01

    Short-term forecast of pertussis incidence is helpful for advanced warning and planning resource needs for future epidemics. By utilizing the Auto-Regressive Integrated Moving Average (ARIMA) model and Exponential Smoothing (ETS) model as alterative models with R software, this paper analyzed data from Chinese Center for Disease Control and Prevention (China CDC) between January 2005 and June 2016. The ARIMA (0,1,0)(1,1,1)12 model (AICc = 1342.2 BIC = 1350.3) was selected as the best performing ARIMA model and the ETS (M,N,M) model (AICc = 1678.6, BIC = 1715.4) was selected as the best performing ETS model, and the ETS (M,N,M) model with the minimum RMSE was finally selected for in-sample-simulation and out-of-sample forecasting. Descriptive statistics showed that the reported number of pertussis cases by China CDC increased by 66.20% from 2005 (4058 cases) to 2015 (6744 cases). According to Hodrick-Prescott filter, there was an apparent cyclicity and seasonality in the pertussis reports. In out of sample forecasting, the model forecasted a relatively high incidence cases in 2016, which predicates an increasing risk of ongoing pertussis resurgence in the near future. In this regard, the ETS model would be a useful tool in simulating and forecasting the incidence of pertussis, and helping decision makers to take efficient decisions based on the advanced warning of disease incidence. PMID:27577101

  14. Status and Trends of GAP Base Construction of Chinese Materia Medica in Guangdong Province

    Institute of Scientific and Technical Information of China (English)

    DING Ping; LAI Xiao-ping; XU Hong-hua; DU Qin; WANG Jian-gang; YING Ge; LIAO Hui-jun; DAI Lei; SHAO Yan-hua

    2012-01-01

    It is one of the key points for modernization and internationalization of traditional Chinese medicines to construct the Good Agricultural Practice (GAP) base of Chinese materia medica (CMM).GAP helps to minimize contamination and improve the quality of CMM during the plantation and the production of Chinese crude drugs.In this article,the status and development of CMM production bases of GAP in Guangdong Province,China,are presented.The suggestions upon the problems during the development of GAP for Chinese crude drugs are also provided.

  15. A Real-time Data Model Based on Temporal Data

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-fang; LIU Yun-sheng

    2006-01-01

    Real-time database systems contain not only transaction timing constraints, but also data timing constraints. This paper discusses the temporal characteristics of data in real-time databases and offers a definition of absolute and relative temporal consistency. In real-time database systems, it is often the case that the policies of transaction schedules only consider the deadline of real-time transactions, making it insufficient to ensure temporal correctness of transactions. A policy is given by considering both the deadlines of transactions and the "data deadline" to schedule real-time transactions. A real-time relational data model and a real-time relational algebra based on the characteristics of temporal data are also proposed. In this model, the temporal data has not only corresponding values, but also validity intervals corresponding to the data values. At the same time, this model is able to keep historical data values. When validity interval of a relation is[NOW,NOW], real-time relational algebra will transform to traditional relational algebra.

  16. Tendência temporal de afastamento do trabalho em servidores públicos (1995-2005 Time trends of sick leave in Brazilian civil servants (1995-2005

    Directory of Open Access Journals (Sweden)

    Jane Bittencourt Cunha

    2009-06-01

    Full Text Available OBJETIVO: Analisar a tendência temporal das taxas de afastamento do trabalho por problemas de saúde de servidores públicos estaduais, das Secretarias de Estado da Saúde e da Administração do Estado de Santa Catarina, no período de 1995 a 2005. MÉTODOS: Estudo ecológico exploratório de séries temporais com utilização de dados secundários. Foram calculadas as taxas de afastamento segundo secretaria, sexo e grupos de patologias. Utilizou-se o procedimento de Prais-Winsten para a análise de tendência. RESULTADOS: Foram analisados 40.370 afastamentos. A tendência das taxas de afastamento foi de decréscimo para ambas as secretarias, considerando ambos os gêneros. Para o gênero feminino da SEA, a tendência foi de estabilidade. As taxas foram mais elevadas na SES. O número médio de dias de afastamento aumentou no decorrer do período analisado. Segundo os grupos de patologias (CID 10, as maiores taxas foram encontradas nos capítulos V, XIII, XXI, XIX e IX. CONCLUSÕES: A tendência de decréscimo das taxas de afastamento e o respectivo aumento da média de dias de afastamento refletem mudanças no perfil de morbidade dos servidores públicos, com o predomínio de transtornos mentais e doenças do sistema osteomuscular, que exigem maior tempo de recuperação para o retorno ao trabalho. O estudo sugere a investigação de fatores associados ao adoecimento que fundamentem as políticas de saúde do servidor.OBJECTIVE: To analyze time trends of sick leave rates among state civil servants in the State Secretariats of Health and of Administration in Santa Catarina, Brazil from 1995 to 2005. METHOD: This is an ecological study with secondary data. Rates of sick leave were calculated according to State Secretariat (Health and Administration, gender, and pathological groups. Prais-Winsten procedure was utilized to analyze trends. RESULTS: 40,370 absences were analyzed. The trend of sick leave rates was decreasing for both State

  17. Time-domain based impedance measurement: strengths and drawbacks

    International Nuclear Information System (INIS)

    While most applications of bio-impedance measurements for characterization of cells or tissue do not have any time requirements, newer developments like real time monitoring of moving cells or membrane recovery after high voltage application depend on fast measurement. This is not compatible with sweeping the frequency through the desired range while assessing magnitude and phase of the material under test (MUT). A high speed is only achievable by using broad-bandwidth excitation signals and monitoring the response in time-domain. Time-domain based methods can be distinguished by the excitation signals as well as by assessing the transmission or reflection behavior of the MUT. Although there is good agreement regarding the advantages of fast measurements, time-domain measurements are often rejected because of low precision and noise sensitivity. This paper points not only the advantages of impedance measurements in time domain but shows also drawbacks together with possible solutions.

  18. Time-frequency representation measurement based on temporal Fourier transformation

    Science.gov (United States)

    Suen, Yifan; Xiao, Shaoqiu; Hao, Sumin; Zhao, Xiaoxiang; Xiong, Yigao; Liu, Shenye

    2016-10-01

    We propose a new scheme to physically realize the short-time Fourier transform (STFT) of chirped optical pulse using time-lens array that enables us to get time-frequency representation without using FFT algorithm. The time-lens based upon the four-wave mixing is used to perform the process of temporal Fourier transformation. Pump pulse is used for both providing the quadratic phase and being the window function of STFT. The idea of STFT is physically realized in our scheme. Simulations have been done to investigate performance of the time-frequency representation scheme (TFRS) in comparison with STFT using FFT algorithm. Optimal measurement of resolution in time and frequency has been discussed.

  19. TIME-RESOLVED PROPERTIES AND GLOBAL TRENDS IN dMe FLARES FROM SIMULTANEOUS PHOTOMETRY AND SPECTRA

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, Adam F.; Hawley, Suzanne L.; Davenport, James R. A. [Astronomy Department, University of Washington, Box 351580, U.W. Seattle, WA 98195-1580 (United States); Wisniewski, John P. [HL Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W Brooks Street, Norman, OK 73019 (United States); Osten, Rachel A. [Space Telescope Science Institute, 3700 San Martin Drive Baltimore, MD 21218 (United States); Hilton, Eric J. [Universe Sandbox, Seattle, WA (United States); Holtzman, Jon A. [Department of Astronomy, New Mexico State University, Box 30001, Las Cruces, NM 88003 (United States); Schmidt, Sarah J., E-mail: adam.f.kowalski@nasa.gov [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)

    2013-07-15

    We present a homogeneous analysis of line and continuum emission from simultaneous high-cadence spectra and photometry covering near-ultraviolet and optical wavelengths for 20 M dwarf flares. These data were obtained to study the white-light continuum components at bluer and redder wavelengths than the Balmer jump. Our goals were to break the degeneracy between emission mechanisms that have been fit to broadband colors of flares and to provide constraints for radiative-hydrodynamic (RHD) flare models that seek to reproduce the white-light flare emission. The main results from the analysis are the following: (1) the detection of Balmer continuum (in emission) that is present during all flares and with a wide range of relative contributions to the continuum flux at bluer wavelengths than the Balmer jump; (2) a blue continuum at flare maximum that is linearly decreasing with wavelength from {lambda} = 4000-4800 A, indicative of hot, blackbody emission with typical temperatures of T{sub BB} {approx} 9000-14, 000 K; (3) a redder continuum apparent at wavelengths longer than H{beta} ({lambda} {approx}> 4900 A) which becomes relatively more important to the energy budget during the late gradual phase. The hot blackbody component and redder continuum component have been detected in previous studies of flares. However, we have found that although the hot blackbody emission component is relatively well-represented by a featureless, single-temperature Planck function, this component includes absorption features and has a continuum shape strikingly similar to the spectrum of an A-type star as directly observed in our flare spectra. New model constraints are presented for the time evolution among the hydrogen Balmer lines and between Ca II K and the blackbody continuum emission. We calculate Balmer jump flux ratios and compare to the solar-type flare heating predictions from RHD models. The model ratios are too large and the blue-optical ({lambda} = 4000-4800 A) slopes are too

  20. Computer-Based Instruction: Roots, Origins, Applications, Benefits, Features, Systems, Trends and Issues.

    Science.gov (United States)

    Hofstetter, Fred T.

    Dealing exclusively with instructional computing, this paper describes how computers are delivering instruction in a wide variety of subjects to students of all ages and explains why computer-based education is currently having a profound impact on education. After a discussion of roots and origins, computer applications are described for…

  1. Creating lift versus building the base : Current trends in marketing dynamics

    NARCIS (Netherlands)

    Leeflang, P.S.H.; Bijmolt, T.H.A.; van Doorn, J.; Hanssens, D.M.; van Heerde, H.J.; Verhoef, P.C.; Wieringa, J.E.

    2009-01-01

    Markets are dynamic by nature; and marketing-efforts can be directed to stimulate, reduce, or to utilize these dynamics. The field of marketing dynamics aims at modeling the effects of marketing actions and policies on short-term performance ("lift") and on long-term performance ("base"). One of the

  2. LDA Based Face Recognition by Using Hidden Markov Model in Current Trends

    Directory of Open Access Journals (Sweden)

    S.Sharavanan

    2009-10-01

    Full Text Available Hidden Markov model (HMM is a promising method that works well for images with variations in lighting, facial expression, and orientation. Face recognition draws attention as a complex task due to noticeable changes produced on appearance by illumination, facial expression, size, orientation and other external factors. To process images using HMM, the temporal or space sequences are to be considered. In simple terms HMM can be defined as set of finite states with associated probability distributions. Only the outcome is visible to the external user not the states and hence the name Hidden Markov Model. The paper deals with various techniques and methodologies used for resolving the problem .We discuss about appearance based, feature based, model based and hybrid methods for face identification. Conventional techniques such as Principal Component Analysis (PCA, Linear Discriminant Analysis (LDA, Independent Component Analysis (ICA, and feature based Elastic Bunch Graph Matching (EBGM and 2D and 3D face models are well-known for face detection and recognition.

  3. Cranial base topology and basic trends in the facial evolution of Homo.

    Science.gov (United States)

    Bastir, Markus; Rosas, Antonio

    2016-02-01

    Facial prognathism and projection are important characteristics in human evolution but their three-dimensional (3D) architectonic relationships to basicranial morphology are not clear. We used geometric morphometrics and measured 51 3D-landmarks in a comparative sample of modern humans (N = 78) and fossil Pleistocene hominins (N = 10) to investigate the spatial features of covariation between basicranial and facial elements. The study reveals complex morphological integration patterns in craniofacial evolution of Middle and Late Pleistocene hominins. A downwards-orientated cranial base correlates with alveolar maxillary prognathism, relatively larger faces, and relatively larger distances between the anterior cranial base and the frontal bone (projection). This upper facial projection correlates with increased overall relative size of the maxillary alveolar process. Vertical facial height is associated with tall nasal cavities and is accommodated by an elevated anterior cranial base, possibly because of relations between the cribriform and the nasal cavity in relation to body size and energetics. Variation in upper- and mid-facial projection can further be produced by basicranial topology in which the midline base and nasal cavity are shifted anteriorly relative to retracted lateral parts of the base and the face. The zygomatics and the middle cranial fossae act together as bilateral vertical systems that are either projected or retracted relative to the midline facial elements, causing either midfacial flatness or midfacial projection correspondingly. We propose that facial flatness and facial projection reflect classical principles of craniofacial growth counterparts, while facial orientation relative to the basicranium as well as facial proportions reflect the complex interplay of head-body integration in the light of encephalization and body size decrease in Middle to Late Pleistocene hominin evolution. Developmental and evolutionary patterns of integration may

  4. Transformer real-time reliability model based on operating conditions

    Institute of Scientific and Technical Information of China (English)

    HE Jian; CHENG Lin; SUN Yuan-zhang

    2007-01-01

    Operational reliability evaluation theory reflects real-time reliability level of power system. The component failure rate varies with operating conditions. The impact of real-time operating conditions such as ambient temperature and transformer MVA (megavolt-ampere) loading on transformer insulation life is studied in this paper. The formula of transformer failure rate based on the winding hottest-spot temperature (HST) is given. Thus the real-time reliability model of transformer based on operating conditions is presented. The work is illustrated using the 1979 IEEE Reliability Test System. The changes of operating conditions are simulated by using hourly load curve and temperature curve, so the curves of real-time reliability indices are obtained by using operational reliability evaluation.

  5. Workshop proceedings:CBRecSys 2014. Workshop on New Trends in Content-based Recommender Systems

    OpenAIRE

    2014-01-01

    While content-based recommendation has been applied successfully in many different domains, it has not seen the same level of attention as collaborative filtering techniques have. In recent years, competitions like the Netflix Prize, CAMRA, and the Yahoo! Music KDD Cup 2011 have spurred on advances in collaborative filtering and how to utilize ratings and usage data. However, there are many domains where content and metadata play a key role, either in addition to or instead of ratings and imp...

  6. A Study on Coastline Extraction and Its Trend Based on Remote Sensing Image Data Mining

    OpenAIRE

    Yun Zhang; Xueming Li; Jianli Zhang; Derui Song

    2013-01-01

    In this paper, data mining theory is applied to carry out the field of the pretreatment of remote sensing images. These results show that it is an effective method for carrying out the pretreatment of low-precision remote sensing images by multisource image matching algorithm with SIFT operator, geometric correction on satellite images at scarce control points, and other techniques; the result of the coastline extracted by the edge detection method based on a chromatic aberration Canny operat...

  7. Clarification of vaccines: An overview of filter based technology trends and best practices.

    Science.gov (United States)

    Besnard, Lise; Fabre, Virginie; Fettig, Michael; Gousseinov, Elina; Kawakami, Yasuhiro; Laroudie, Nicolas; Scanlan, Claire; Pattnaik, Priyabrata

    2016-01-01

    Vaccines are derived from a variety of sources including tissue extracts, bacterial cells, virus particles, recombinant mammalian, yeast and insect cell produced proteins and nucleic acids. The most common method of vaccine production is based on an initial fermentation process followed by purification. Production of vaccines is a complex process involving many different steps and processes. Selection of the appropriate purification method is critical to achieving desired purity of the final product. Clarification of vaccines is a critical step that strongly impacts product recovery and subsequent downstream purification. There are several technologies that can be applied for vaccine clarification. Selection of a harvesting method and equipment depends on the type of cells, product being harvested, and properties of the process fluids. These techniques include membrane filtration (microfiltration, tangential-flow filtration), centrifugation, and depth filtration (normal flow filtration). Historically vaccine harvest clarification was usually achieved by centrifugation followed by depth filtration. Recently membrane based technologies have gained prominence in vaccine clarification. The increasing use of single-use technologies in upstream processes necessitated a shift in harvest strategies. This review offers a comprehensive view on different membrane based technologies and their application in vaccine clarification, outlines the challenges involved and presents the current state of best practices in the clarification of vaccines.

  8. New trends in nuclear research based on laser Compton scattering γ-ray beams

    International Nuclear Information System (INIS)

    Laser Compton scattering (LCS) γ-ray has a number of advantages not found in other γ-ray sources, such as quasi-monochrome, variable energy, beam profile, and capability of linear (circular) polarization, and has been used in various fields including nuclear physics research. This paper discusses the development situation of the high-intensity LCS γ-ray source of new generation, as well as the possibility of photonuclear physics. The high-brightness LCS γ-ray source of new generation with the magnitude higher by 4-7 orders than the conventional LCS γ-ray was proposed, and its construction has already been started in Europe. The LCS γ-ray based on energy recovery linac (ERL) was proposed in Japan, too. KEK performed electron acceleration due to compact ERL for demonstrating the principle, and is generating the LCS γ-ray of approximately 7 keV, using a laser stacking cavity built into a compact ERL. As for the studies on photonuclear physics, the following items are reviewed: Studies on nuclear structure based on linearly polarized γ-ray, studies on supernova explosion based on photonuclear reaction, determination of the reaction cross-sectional area of 12C(α,γ)16O in nuclear astrophysics, photonuclear fission, parity non-conservation due to circularly polarized γ-ray, and Delbruck scattering as one of the nonlinear effect of QED. (A.O.)

  9. A Comparative Study of Content Based Image Retrieval Trends and Approaches

    Directory of Open Access Journals (Sweden)

    Satish Tunga

    2015-05-01

    Full Text Available Content Based Image Retrieval (CBIR is an important step in addressing image storage and management problems. Latest image technology improvements along with the Internet growth have led to a huge amount of digital multimedia during the recent decades. Various methods, algorithms and systems have been proposed to solve these problems. Such studies revealed the indexing and retrieval concepts, which have further evolved to Content-Based Image Retrieval. CBIR systems often analyze image content via the so-called low-level features for indexing and retrieval, such as color, texture and shape. In order to achieve significantly higher semantic performance, recent systems seek to combine low-level with high-level features that contain perceptual information for human. Purpose of this review is to identify the set of methods that have been used for CBR and also to discuss some of the key contributions in the current decade related to image retrieval and main challenges involved in the adaptation of existing image retrieval techniques to build useful systems that can handle real-world data. By making use of various CBIR approaches accurate, repeatable, quantitative data must be efficiently extracted in order to improve the retrieval accuracy of content-based image retrieval systems. In this paper, various approaches of CBIR and available algorithms are reviewed. Comparative results of various techniques are presented and their advantages, disadvantages and limitations are discussed.

  10. Predicting future trends in stock market by decision tree rough-set based hybrid system with HHMM

    Directory of Open Access Journals (Sweden)

    Shweta Tiwari

    2012-06-01

    Full Text Available Around the world, trading in the stock market has gained huge attractiveness as a means through which, one can obtain vast profits. Attempting to profitably and precisely predict the financial market has long engrossed the interests and attention of bankers, economists and scientists alike. Stock market prediction is the act of trying, to determine the future value of a company’s stock or other financial instrument traded on a financial exchange. Accurate stock market predictions are important for many reasons. Chief among all is the need for investors, to hedge against potential market risks and the opportunities for arbitrators and speculators, to make profits by trading indexes. Stock Market is a place, where shares are issued and traded. These shares are either traded through Stock exchanges or Overthe-Counter in physical or electronic form. Data mining, as a process of discovering useful patterns, correlations has its own role in financial modeling. Data mining is a discipline in computational intelligence that deals with knowledge discovery, data analysis and full and semi-autonomous decision making. Prediction of stock market by data mining techniques has been receiving a lot of attention recently. This paper presents a hybrid system based on decision tree- rough set, for predicting the trends in the Bombay Stock Exchange (BSESENSEX with the combination of Hierarchical Hidden Markov Model. In this paper we present future trends on the bases of price earnings and dividend. The data on accounting earnings when averaged over many years help to predict the present value of future dividends.

  11. Performance Analysis of STFT Based Timing Approach to OFDM Systems

    Institute of Scientific and Technical Information of China (English)

    KUANG Yu-jun; TENG Yong; YIN Chang-chuan; HAO Jian-jun; YUE Guang-xin

    2003-01-01

    This paper mainly focuses on performance analysis of the previously proposed STFT based 2-D timing approach to OFDM systems and presents simulations results of its performance in AWGN and multipath fading environment and its robustness against the duration of Channel Impulse Response (CIR) and frequency offset. Simulation results suggest that a revised version of Short-Time Fourier Transform (STFT) can be used to greatly reduce computational complexity, especially at higher SNR.

  12. Assessing woody vegetation trends in Sahelian drylands using MODIS based seasonal metrics

    DEFF Research Database (Denmark)

    Brandt, Martin Stefan; Hiernaux, Pierre; Rasmussen, Kjeld;

    2016-01-01

    Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500 m) derived...... of low anthropogenic pressure demonstrating the potential of these ecosystems to provide services such as carbon storage, if not over-utilized. Taken together, our results provide an unprecedented synthesis of woody cover dynamics in the Sahel, and point to land use and human population density...

  13. Data-based controllability analysis of discrete-time linear time-delay systems

    Science.gov (United States)

    Liu, Yang; Chen, Hong-Wei; Lu, Jian-Quan

    2014-11-01

    In this paper, a data-based method is used to analyse the controllability of discrete-time linear time-delay systems. By this method, one can directly construct a controllability matrix using the measured state data without identifying system parameters. Hence, one can save time in practice and avoid corresponding identification errors. Moreover, its calculation precision is higher than some other traditional approaches, which need to identify unknown parameters. Our methods are feasible to the study of characteristics of deterministic systems. A numerical example is given to show the advantage of our results.

  14. Finite-time synchronization of fractional-order memristor-based neural networks with time delays.

    Science.gov (United States)

    Velmurugan, G; Rakkiyappan, R; Cao, Jinde

    2016-01-01

    In this paper, we consider the problem of finite-time synchronization of a class of fractional-order memristor-based neural networks (FMNNs) with time delays and investigated it potentially. By using Laplace transform, the generalized Gronwall's inequality, Mittag-Leffler functions and linear feedback control technique, some new sufficient conditions are derived to ensure the finite-time synchronization of addressing FMNNs with fractional order α:1neural networks. Finally, three numerical examples are presented to show the effectiveness of our proposed theoretical results.

  15. Statistical properties of Fourier-based time-lag estimates

    CERN Document Server

    Epitropakis, A

    2016-01-01

    Context: The study of X-ray time-lag spectra in AGN is currently an active research area, as it has the potential to illuminate the physics and geometry of the innermost region (i.e. close to the putative super-massive black hole) in these objects. In order to obtain reliable information from these studies, the statistical properties of time-lags estimated from data must be known as accurately as possible. Aims: We investigated the statistical properties of Fourier-based time-lag estimates (i.e. based on the cross-periodogram), using evenly sampled time series with no missing points. Our aim is to provide practical "guidelines" on estimating time-lags which are minimally biased (i.e. whose mean is close to their intrinsic value) and have known errors. Methods: Our investigation is based on both analytical work and extensive numerical simulations. The latter consisted of generating artificial time series with various signal-to-noise ratios and sampling patterns/durations similar to those offered by AGN observa...

  16. Non-coherent space-time code based on full diversity space-time block coding

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A non-unitary non-coherent space-time code which is capable of achieving full algebraic diversity is proposed based on full diversity space-time block coding. The error performance is optimized by transforming the non-unitary space-time code into unitary space-time code. By exploiting the desired structure of the proposed code, a grouped generalized likelihood ratio test decoding algorithm is presented to overcome the high complexity of the optimal algorithm. Simulation results show that the proposed code possesses high spectrum efficiency in contrast to the unitary space-time code despite slight loss in the SNR, and besides, the proposed grouped decoding algorithm provides good tradeoff between performance and complexity.

  17. Is CT-based perfusion and collateral imaging sensitive to time since stroke onset?

    Directory of Open Access Journals (Sweden)

    Smriti eAgarwal

    2015-04-01

    Full Text Available Abstract PurposeCT-based perfusion and collateral imaging is increasingly used in the assessment of patients with acute stroke. Time of stroke onset is a critical factor in determining eligibility for and benefit from thrombolysis. Animal studies predict that the volume of ischemic penumbra decreases with time. Here we evaluate if CT is able to detect a relationship between perfusion or collateral status, as assessed by CT and time since stroke onset.Materials and MethodsWe studied fifty-three consecutive patients with proximal vessel occlusions, mean (SD age of 71.3 (14.9 years at a mean (SD of 125.2 (55.3 minutes from onset, using whole-brain CT perfusion (CTp imaging. Penumbra was defined using voxel-based thresholds for cerebral blood flow (CBF and mean transit time (MTT; core was defined by cerebral blood volume (CBV. Normalized penumbra fraction was calculated as Penumbra volume /(Penumbra volume +Core volume for both CBF and MTT (PenCBF and PenMTT, respectively. Collaterals were assessed on CT angiography (CTA. CTp ASPECTS score was applied visually, lower scores indicating larger lesions. ASPECTS ratios were calculated corresponding to penumbra fractions.ResultsBoth PenCBF and PenMTT showed decremental trends with increasing time since onset (Kendall’s tau-b=-0.196, p=0.055, and -0.187, p=0.068, respectively. The CBF/CBV ASPECTS ratio, which showed a relationship to PenCBF (Kendall’s tau-b=0.190, p=0.070, decreased with increasing time since onset (Kendall’s tau-b=-0.265, p=0.006. Collateral response did not relate to time (Kendall’s tau-b=-0.039, p=0.724.ConclusionEven within 4.5hrs since stroke onset, a decremental relationship between penumbra and time, but not between collateral status and time, may be detected using perfusion CT imaging. The trends that we demonstrate merit evaluation in larger datasets to confirm our results, which may have potential wider applications e.g. in the setting of strokes of unknown onset time.

  18. Real time gesture based control: A prototype development

    Science.gov (United States)

    Bhargava, Deepshikha; Solanki, L.; Rai, Satish Kumar

    2016-03-01

    The computer industry is getting advanced. In a short span of years, industry is growing high with advanced techniques. Robots have been replacing humans, increasing the efficiency, accessibility and accuracy of the system and creating man-machine interaction. Robotic industry is developing many new trends. However, they still need to be controlled by humans itself. This paper presents an approach to control a motor like a robot with hand gestures not by old ways like buttons or physical devices. Controlling robots with hand gestures is very popular now-a-days. Currently, at this level, gesture features are applied for detecting and tracking the hand in real time. A principal component analysis algorithm is being used for identification of a hand gesture by using open CV image processing library. Contours, convex-hull, and convexity defects are the gesture features. PCA is a statistical approach used for reducing the number of variables in hand recognition. While extracting the most relevant information (feature) contained in the images (hand). After detecting and recognizing hand a servo motor is being controlled, which uses hand gesture as an input device (like mouse and keyboard), and reduces human efforts.

  19. Musical Sound Separation Based on Binary Time-Frequency Masking

    Directory of Open Access Journals (Sweden)

    Wang DeLiang

    2009-01-01

    Full Text Available The problem of overlapping harmonics is particularly acute in musical sound separation and has not been addressed adequately. We propose a monaural system based on binary time-frequency masking with an emphasis on robust decisions in time-frequency regions, where harmonics from different sources overlap. Our computational auditory scene analysis system exploits the observation that sounds from the same source tend to have similar spectral envelopes. Quantitative results show that utilizing spectral similarity helps binary decision making in overlapped time-frequency regions and significantly improves separation performance.

  20. Collaborative Simulation Run-time Management Environment Based on HLA

    Institute of Scientific and Technical Information of China (English)

    王江云; 柴旭东; 王行仁

    2002-01-01

    The Collaborative Simulation Run-time Management Environment based on HLA (CSRME) mainly focuses on simulation problems for the system design of the complex distributed simulation. CSRME can integrate all the simulation tools and simulation applications that comply with the well-documented interface standards defined by CSRME. CSRME supports both the interoperability of different simulations and the integration of simulation tools, as well as provides simulation run-time management, simulation time management and simulation data management. Finally, the distributed command training system is analyzed and realized to validate the theories of CSRME.

  1. Method for Real-Time Model Based Structural Anomaly Detection

    Science.gov (United States)

    Smith, Timothy A. (Inventor); Urnes, James M., Sr. (Inventor); Reichenbach, Eric Y. (Inventor)

    2015-01-01

    A system and methods for real-time model based vehicle structural anomaly detection are disclosed. A real-time measurement corresponding to a location on a vehicle structure during an operation of the vehicle is received, and the real-time measurement is compared to expected operation data for the location to provide a modeling error signal. A statistical significance of the modeling error signal to provide an error significance is calculated, and a persistence of the error significance is determined. A structural anomaly is indicated, if the persistence exceeds a persistence threshold value.

  2. Study on autonomous navigation based on pulsar timing model

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The basic principle of pulsar timing model was introduced, and the general relativistic corrections were analyzed when pulse time of arrival (TOA) was transferred to coordinate TOA at the Solar System Barycentre. Based on the shifting, an iterative method of autonomous position determination for spacecraft was developed. Accordingly, the linear form of the position offset equation was evolved. Using the initial estimated value of spacecraft’s position as the input of pulsar timing equation, through calculation of the offset between measured or transferred and predicted TOA, the position offset can be solved by Least Squares. At last, the main error sources including modeling error and parameters error were discussed.

  3. Filter model based dwell time algorithm for ion beam figuring

    Science.gov (United States)

    Li, Yun; Xing, Tingwen; Jia, Xin; Wei, Haoming

    2010-10-01

    The process of Ion Beam Figuring (IBF) can be described by a two-dimensional convolution equation which including dwell time. Solving the dwell time is a key problem in IBF. Theoretically, the dwell time can be solved from a two-dimensional deconvolution. However, it is often ill-posed]; the suitable solution of that is hard to get. In this article, a dwell time algorithm is proposed, depending on the characters of IBF. Usually, the Beam Removal Function (BRF) in IBF is Gaussian, which can be regarded as a headstand Gaussian filter. In its stop-band, the filter has various filtering abilities for various frequencies. The dwell time algorithm proposed in this article is just based on this concept. The Curved Surface Smooth Extension (CSSE) method and Fast Fourier Transform (FFT) algorithm are also used. The simulation results show that this algorithm is high precision, effective, and suitable for actual application.

  4. Vehicle Travel Time Predication based on Multiple Kernel Regression

    Directory of Open Access Journals (Sweden)

    Wenjing Xu

    2014-07-01

    Full Text Available With the rapid development of transportation and logistics economy, the vehicle travel time prediction and planning become an important topic in logistics. Travel time prediction, which is indispensible for traffic guidance, has become a key issue for researchers in this field. At present, the prediction of travel time is mainly short term prediction, and the predication methods include artificial neural network, Kaman filter and support vector regression (SVR method etc. However, these algorithms still have some shortcomings, such as highcomputationcomplexity, slow convergence rate etc. This paper exploits the learning ability of multiple kernel learning regression (MKLR in nonlinear prediction processing characteristics, logistics planning based on MKLR for vehicle travel time prediction. The method for Vehicle travel time prediction includes the following steps: (1 preprocessing historical data; (2 selecting appropriate kernel function, training the historical data and performing analysis ;(3 predicting the vehicle travel time based on the trained model. The experimental results show that, through the analysis of using different methods for prediction, the vehicle travel time prediction method proposed in this paper, archives higher accuracy than other methods. It also illustrates the feasibility and effectiveness of the proposed prediction method.

  5. Trends in Mortality Disparities by Area-Based Poverty in New York City, 1990-2010.

    Science.gov (United States)

    Toprani, Amita; Li, Wenhui; Hadler, James L

    2016-06-01

    Residing in a high-poverty area has consistently been associated with higher mortality rates, but the association between poverty and mortality can change over time. We examine the association between neighborhood poverty and mortality in New York City (NYC) during 1990-2010 to document mortality disparity changes over time and determine causes of death for which disparities are greatest. We used NYC and New York state mortality data for years 1990, 2000, and 2010 to calculate all-cause and cause-specific age-adjusted death rates (AADRs) by census tract poverty (CTP), which is the proportion of persons in a census tract living below the federal poverty threshold. We calculated mortality disparities, measured as the difference in AADR between the lowest and highest CTP groups, within and across race/ethnicity, nativity, and sex categories by year. We observed higher all-cause AADRs with higher CTP for each year for all race/ethnicities, both sexes, and US-born persons. Mortality disparities decreased progressively during 1990-2010 for the NYC population overall, for each race/ethnic group, and for the majority of causes of death. The overall mortality disparity between the highest and lowest CTP groups during 2010 was 2.55 deaths/1000 population. The largest contributors to mortality disparities were heart disease (51.52 deaths/100,000 population), human immunodeficiency virus (19.96/100,000 population), and diabetes (19.59/100,000 population). We show that progress was made in narrowing socioeconomic disparities in mortality during 1990-2010, but substantial disparities remain. Future efforts toward achieving health equity in NYC mortality should focus on areas contributing most to disparities. PMID:27177681

  6. Trends and variability in summer sea ice cover in the Canadian Arctic based on the Canadian Ice Service Digital Archive

    Science.gov (United States)

    Howell, S.; Tivy, A. C.; Alt, B.; McCourt, S.; Chagnon, R.; Crocker, G.; Carrieres, T. G.; Yackel, J.

    2010-12-01

    The Canadian Ice Service Digital Archive (CISDA) is a compilation of weekly ice charts that cover Canadian Waters; the data set is continually updated and it extends back to the early 1960s. The ice charts are represent and integration of remotely sensed sea ice data, surface observations, airborne and ship reports, operational model results and the expertise of experience ice forecasters. Although the accuracy, type and detail of information far exceeds what is attainable from a single satellite source, errors and uncertainties in the data are non-uniform in both space and time. In part one of this study the main sources of uncertainty in the database are reviewed and the data are validated for use in climate studies. In part two, trends and variability in summer sea ice in the Canadian Arctic are investigated using CISDA. These data revealed that between 1968 and 2008, summer sea ice cover has decreased by 8.9% ± 3.1% per decade in Hudson Bay, 2.9% ± 1.2% per decade in the Canadian Arctic Archipelago, 8.9% ± 3.1% per decade in Baffin Bay, and 5.2% ± 2.4% per decade in the Beaufort Sea. In general, these reductions in sea ice cover are linked to increases in early summer surface air temperature (SAT); significant increases in SAT were observed in every season and with the exception of the Hudson Bay region they are consistently greater than the pan-Arctic change by up to ~0.2oC per decade. Within the Canadian Arctic Archipelago and Baffin Bay, the El Niño-Southern Oscillation (ENSO) index correlates well with multi-year ice coverage (positive correlation) and first-year ice coverage (negative correlation) suggesting that El Nino episodes precede summers with more multi-year ice and less first-year ice. Extending the trend calculations back to 1960 along the major shipping routes through the Canadian Arctic revealed significant decreases in summer sea ice coverage ranging between 11% and 15% per decade along the shipping route through Hudson Bay, the western

  7. Time based management in health care system: The chosen aspects

    Directory of Open Access Journals (Sweden)

    Joanna Kobza

    2014-08-01

    Full Text Available Time-based management (TBM is the key element of the whole management process. For many years in health care systems of highly developed countries modern and effective methods of time-based management have been implemented in both primary health care and hospitals (emergency departments and operating rooms. Over the past two decades a systematic review of Polish literature (since 1990 and peer reviewed articles published in international journals based on PubMed/Medline (2001–2011 have been carried out. The collected results indicate that the demographic and health changes in the populations are one of the main challenges facing general practitioners in the nearest future. Time-based management needs new and effective tools and skills, i.e., identification of priorities, well designed planning, delegation of the tasks, proper coordination, and creation of primary care teams that include additional members and human resources management. Proper reimbursement of health services, development of IT in health care system, better collection, storage, processing, analysis and exchange of information and research findings will also be needed. The use of innovative technologies, like telemedicine consultations, provides the possibility of reducing waiting time for diagnosis and treatment and in some cases could be applied in terms of secondary care. To improve the efficiency of operating rooms it is necessary to introduce different solutions, such as operating room coordinator involvement, application of automation to guide decision-making or use of robotic tools to assist surgical procedures. Overcrowded emergency departments have a major detrimental effect on the quality of hospital functions, therefore, efforts should be made to reduce them. Time-based management training among physicians and health care management in Poland, as well as the implementation of practice-based solutions still applied in highly developed countries seem to be necessary

  8. Optimisation of sensing time and transmission time in cognitive radio-based smart grid networks

    Science.gov (United States)

    Yang, Chao; Fu, Yuli; Yang, Junjie

    2016-07-01

    Cognitive radio (CR)-based smart grid (SG) networks have been widely recognised as emerging communication paradigms in power grids. However, a sufficient spectrum resource and reliability are two major challenges for real-time applications in CR-based SG networks. In this article, we study the traffic data collection problem. Based on the two-stage power pricing model, the power price is associated with the efficient received traffic data in a metre data management system (MDMS). In order to minimise the system power price, a wideband hybrid access strategy is proposed and analysed, to share the spectrum between the SG nodes and CR networks. The sensing time and transmission time are jointly optimised, while both the interference to primary users and the spectrum opportunity loss of secondary users are considered. Two algorithms are proposed to solve the joint optimisation problem. Simulation results show that the proposed joint optimisation algorithms outperform the fixed parameters (sensing time and transmission time) algorithms, and the power cost is reduced efficiently.

  9. Multi Band Insar Analysis of Subsidence Development Based on the Long Period Time Series

    Science.gov (United States)

    Çomut, F. C.; Ustun, A.; Lazecky, M.; Aref, M. M.

    2015-12-01

    The SAR Interferometry (InSAR) application has shown great potential in monitoring of land terrain changes and in detection of land deformations such as subsidence. Longer time analysis can lead to understand longer trends and changes. Using different bands of SAR satellite (C- from ERS 1-2 and Envisat, L- from ALOS) over the study area, we achieve knowledge of movements in long-term and evaluation of its dynamic changes within observed period of time. Results from InSAR processing fit with the position changes in vertical direction based on GPS network established over the basin as an effective geodetic network. Time series (StaMPS PS+SB) of several points over Çumra County in eastern part of Konya City show a general trend of the deformation that is expected to be approximately between -13 to -17 mm/year. Northern part of Karaman is affected by faster subsidence, borders of the subsidence trough were identified from Envisat. Presenting InSAR results together with GIS information about locations and time of occurrence of sudden subsidence, urban/industrial growth in time and climate changes helps in better understanding of the situation. This way, the impact of natural and man-made changes will be shown for urban planning thanks to InSAR and GIS comparisons with hydrogeological modeling. In this study we present results of differential and multitemporal InSAR series using different bands and GIS conjunction associated with seasonal and temporal groundwater level changes in Konya Closed Basin.

  10. MULTI BAND INSAR ANALYSIS OF SUBSIDENCE DEVELOPMENT BASED ON THE LONG PERIOD TIME SERIES

    Directory of Open Access Journals (Sweden)

    F. C. Çomut

    2015-12-01

    Full Text Available The SAR Interferometry (InSAR application has shown great potential in monitoring of land terrain changes and in detection of land deformations such as subsidence. Longer time analysis can lead to understand longer trends and changes. Using different bands of SAR satellite (C- from ERS 1-2 and Envisat, L- from ALOS over the study area, we achieve knowledge of movements in long-term and evaluation of its dynamic changes within observed period of time. Results from InSAR processing fit with the position changes in vertical direction based on GPS network established over the basin as an effective geodetic network. Time series (StaMPS PS+SB of several points over Çumra County in eastern part of Konya City show a general trend of the deformation that is expected to be approximately between -13 to -17 mm/year. Northern part of Karaman is affected by faster subsidence, borders of the subsidence trough were identified from Envisat. Presenting InSAR results together with GIS information about locations and time of occurrence of sudden subsidence, urban/industrial growth in time and climate changes helps in better understanding of the situation. This way, the impact of natural and man-made changes will be shown for urban planning thanks to InSAR and GIS comparisons with hydrogeological modeling. In this study we present results of differential and multitemporal InSAR series using different bands and GIS conjunction associated with seasonal and temporal groundwater level changes in Konya Closed Basin.

  11. Monitoring Phenological Trends From Satellite Imagery

    Science.gov (United States)

    Reed, B.; Brown, J.; Whalen, A.

    2004-12-01

    While there is convincing evidence that global climate change is taking place, there is still considerable controversy over the magnitude and consequences of any changes. One of the primary manifestations of climate change is the effect on patterns of vegetation growth; the timing of the growing season, the vigor of vegetation, and vegetation composition. The satellite data record provides an objective view of vegetation activity by measuring surface reflectance values at regular time intervals. Time-series analyses of satellite data can provide information on emerging trends of vegetation dynamics that may be related to global change. The objective of this project is to conduct a trend analysis of vegetation dynamics in the conterminous United States, as measured by satellite data, to assess regions of changing vegetation activity, and to evaluate the regions to determine the driving forces of these changes. To assess vegetation dynamics we analyze phenological metrics (e.g., time of start of season , end of season, duration of season, and seasonally integrated greenness) derived from satellite data and evaluate trends in these metrics by studying the climate record, agricultural statistics, and land cover data bases to assess the driving forces of the trends. The types of trends that we identify include trends toward earlier/later start and end of season, longer/shorter growing seasons, and greater/lesser vegetation production. Early results indicate geographically specific drivers across various ecoregions of the US.

  12. Paraconsistent intelligent-based systems new trends in the applications of paraconsistency

    CERN Document Server

    2015-01-01

    This book presents some of the latest applications of new theories based on the concept of paraconsistency and correlated topics in informatics, such as pattern recognition (bioinformatics), robotics, decision-making themes, and sample size. Each chapter is self-contained, and an introductory chapter covering the logic theoretical basis is also included. The aim of the text is twofold: to serve as an introductory text on the theories and applications of new logic, and as a textbook for undergraduate or graduate-level courses in AI. Today AI frequently has to cope with problems of vagueness, incomplete and conflicting (inconsistent) information. One of the most notable formal theories for addressing them is paraconsistent (paracomplete and non-alethic) logic. .

  13. Reaping the space investment. [Shuttle era geosynchronous satellite based technological trends

    Science.gov (United States)

    Calio, A. J.

    1979-01-01

    By 1999 operational space systems will be implemented routinely on a worldwide scale in many areas vital to human survival and life quality. Geosynchronous-based monitoring and observation will be extensively used. The Shuttle era will bring in the capability to allow monitoring and identifying pollution sources which fail to stay within required limits. Remotely sensed data over land masses will provide needed facts on renewable and nonrenewable earth resources. New instruments and techniques will have been developed to provide geologists with clues to the declining number of deposits of fuels and minerals. Also, practical methods for predicting earthquakes will have been elaborated by 1999. Communications will see implementation of many of the technological goals of 1978.

  14. Biorefinery based on olive biomass. State of the art and future trends.

    Science.gov (United States)

    Romero-García, J M; Niño, L; Martínez-Patiño, C; Álvarez, C; Castro, E; Negro, M J

    2014-05-01

    With currently more than nine million hectares, olive tree cultivation has spread worldwide, table olives and olive oil as the main products. Moreover, a number of by-products and residues derived from both tree cultivation and the process of industrial olive oil production, most having no practical applications, are obtained yearly. This paper reviews the research regarding these by-products, namely biomass from olive tree pruning, olive stones, olive pomace and wastewaters obtained from the process of olive oil production. Furthermore, a wide range of compounds has been identified and can be produced using a broad definition of the term biorefinery based on olive tree biomass. As an example, this paper reviews ethanol production as one of the main proposed applications, as well as research on other value-added products. Finally, this paper also assesses recent technological advances, future perspectives and challenges in each stage of the process.

  15. Statistical properties of Fourier-based time-lag estimates

    Science.gov (United States)

    Epitropakis, A.; Papadakis, I. E.

    2016-06-01

    Context. The study of X-ray time-lag spectra in active galactic nuclei (AGN) is currently an active research area, since it has the potential to illuminate the physics and geometry of the innermost region (i.e. close to the putative super-massive black hole) in these objects. To obtain reliable information from these studies, the statistical properties of time-lags estimated from data must be known as accurately as possible. Aims: We investigated the statistical properties of Fourier-based time-lag estimates (i.e. based on the cross-periodogram), using evenly sampled time series with no missing points. Our aim is to provide practical "guidelines" on estimating time-lags that are minimally biased (i.e. whose mean is close to their intrinsic value) and have known errors. Methods: Our investigation is based on both analytical work and extensive numerical simulations. The latter consisted of generating artificial time series with various signal-to-noise ratios and sampling patterns/durations similar to those offered by AGN observations with present and past X-ray satellites. We also considered a range of different model time-lag spectra commonly assumed in X-ray analyses of compact accreting systems. Results: Discrete sampling, binning and finite light curve duration cause the mean of the time-lag estimates to have a smaller magnitude than their intrinsic values. Smoothing (i.e. binning over consecutive frequencies) of the cross-periodogram can add extra bias at low frequencies. The use of light curves with low signal-to-noise ratio reduces the intrinsic coherence, and can introduce a bias to the sample coherence, time-lag estimates, and their predicted error. Conclusions: Our results have direct implications for X-ray time-lag studies in AGN, but can also be applied to similar studies in other research fields. We find that: a) time-lags should be estimated at frequencies lower than ≈ 1/2 the Nyquist frequency to minimise the effects of discrete binning of the

  16. Timing-Driven Nonuniform Depopulation-Based Clustering

    Directory of Open Access Journals (Sweden)

    Hanyu Liu

    2010-01-01

    hence improve routability by spreading the logic over the architecture. However, all depopulation-based clustering algorithms to this date increase critical path delay. In this paper, we present a timing-driven nonuniform depopulation-based clustering technique, T-NDPack, that targets critical path delay and channel width constraints simultaneously. T-NDPack adjusts the CLB capacity based on the criticality of the Basic Logic Element (BLE. Results show that T-NDPack reduces minimum channel width by 11.07% while increasing the number of CLBs by 13.28% compared to T-VPack. More importantly, T-NDPack decreases critical path delay by 2.89%.

  17. Research on time series mining based on shape concept time warping

    Institute of Scientific and Technical Information of China (English)

    翁颖钧; 朱仲英

    2004-01-01

    Time series is an important kind of complex data, while a growing attention has been paid to mining time series knowledge recently. Typically Euclidean distance measure is used for comparing time series. However, it may be a brittle distance measure because of less robustness. Dynamic time warp is a pattern matching algorithm based on nonlinear dynamic programming technique, however it is computationally expensive and suffered from the local shape variance. A modification algorithm named by shape DTW is presented, which uses linguistic variable concept to describe the slope feather of time series. The concept tree is developed by cloud models theory which integrates randomness and probability of uncertainty, so that it makes conversion between qualitative and quantitive knowledge. Experiments about cluster analysis on the basis of this algorithm, compared with Euclidean measure, are implemented on synthetic control chart time series. The results show that this method has strong robustness to loss of feature data due to piecewise segment preprocessing. Moreover, after the construction of shape concept tree, we can discovery knowledge of time series on different time granularity.

  18. Hierarchical Real-time Network Traffic Classification Based on ECOC

    Directory of Open Access Journals (Sweden)

    Yaou Zhao

    2013-09-01

    Full Text Available Classification of network traffic is basic and essential for manynetwork researches and managements. With the rapid development ofpeer-to-peer (P2P application using dynamic port disguisingtechniques and encryption to avoid detection, port-based and simplepayload-based network traffic classification methods were diminished.An alternative method based on statistics and machine learning hadattracted researchers' attention in recent years. However, most ofthe proposed algorithms were off-line and usually used a single classifier.In this paper a new hierarchical real-time model was proposed which comprised of a three tuple (source ip, destination ip and destination portlook up table(TT-LUT part and layered milestone part. TT-LUT was used to quickly classify short flows whichneed not to pass the layered milestone part, and milestones in layered milestone partcould classify the other flows in real-time with the real-time feature selection and statistics.Every milestone was a ECOC(Error-Correcting Output Codes based model which was usedto improve classification performance. Experiments showed that the proposedmodel can improve the efficiency of real-time to 80%, and themulti-class classification accuracy encouragingly to 91.4% on the datasets which had been captured from the backbone router in our campus through a week.

  19. Hardware Algorithms For Tile-Based Real-Time Rendering

    NARCIS (Netherlands)

    Crisu, D.

    2012-01-01

    In this dissertation, we present the GRAphics AcceLerator (GRAAL) framework for developing embedded tile-based rasterization hardware for mobile devices, meant to accelerate real-time 3-D graphics (OpenGL compliant) applications. The goal of the framework is a low-cost, low-power, high-performance d

  20. Real-time web-based telerehabilitation monitoring.

    Science.gov (United States)

    Lewis, Jeffrey; Boian, Rares; Burdea, Grigore; Deutsch, Judith

    2003-01-01

    Distance monitoring of rehabilitation exercises has been primarily conducted using two-way video conferencing. This paper presents a real-time web-based monitoring system that greatly enhances the capability of the clinician to direct rehabilitation therapies. PMID:15455890