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Sample records for tributaries potential effects

  1. Pesticide presence in Great Lakes tributaries and comparison to ToxCast and other water quality benchmarks to screen for potential biological effects

    Science.gov (United States)

    Product Description:Pesticides are a broad category of current use chemicals that pose potential threats to aquatic organisms in and around the Great Lakes basin. In this study, we monitored for over 200 pesticides or their break down products in 16 major tributaries to the Great...

  2. Potential Relationships Between Urban Development and the Trophic Status of Tampa Bay Tributaries and Lake Thonotosassa, Further the Potential Effect on Public Health

    Science.gov (United States)

    MorenoMadrinan, Max J.; Allhamdan, Mohammad; Rickman, Douglas L.; Estes, Maury

    2010-01-01

    This slide presentation reviews the use of remote sensing to monitor the relationships between the urban development and water quality in Tampa Bay and the tributaries. It examines the changes in land cover/land use (LU/LC) and the affects that this change has on the water quality of Tampa Bay, Lake Thonotosassa and the tributaries, and that shows the ways that these changes can be estimated with remote sensing.

  3. RUNOFF POTENTIAL OF MUREŞ RIVER UPPER BASIN TRIBUTARIES

    Directory of Open Access Journals (Sweden)

    V. SOROCOVSCHI

    2012-03-01

    Full Text Available Runoff Potential of Mureş River Upper Basin Tributaries. The upper basin of the Mureş River includes a significant area of the Eastern Carpathians central western part with different runoff formation conditions. In assessing the average annual runoff potential we used data from six gauging stations and made assessments on three distinct periods. Identifying the appropriate areas of the obtained correlations curves (between specific average runoff and catchments mean altitude allowed the assessment of potential runoff at catchment level and on geographical units. The potential average runoff is also assessed on altitude intervals of the mentioned areas. The runoff potential analysis on hydrographic basins, geographical units and altitude intervals highlights the variant spatial distribution of this general water resources indicator in the different studied areas.

  4. Organic contaminants in Great Lakes tributaries: Prevalence and potential aquatic toxicity

    Science.gov (United States)

    Baldwin, Austin K.; Corsi, Steven R.; De Cicco, Laura A.; Lenaker, Peter L.; Lutz, Michelle A; Sullivan, Daniel J.; Richards, Kevin D.

    2016-01-01

    Organic compounds used in agriculture, industry, and households make their way into surface waters through runoff, leaking septic-conveyance systems, regulated and unregulated discharges, and combined sewer overflows, among other sources. Concentrations of these organic waste compounds (OWCs) in some Great Lakes tributaries indicate a high potential for adverse impacts on aquatic organisms. During 2010–13, 709 water samples were collected at 57 tributaries, together representing approximately 41% of the total inflow to the lakes. Samples were collected during runoff and low-flow conditions and analyzed for 69 OWCs, including herbicides, insecticides, polycyclic aromatic hydrocarbons, plasticizers, antioxidants, detergent metabolites, fire retardants, non-prescription human drugs, flavors/fragrances, and dyes. Urban-related land cover characteristics were the most important explanatory variables of concentrations of many OWCs. Compared to samples from nonurban watersheds ( 15% urban land cover) had nearly four times the number of detected compounds and four times the total sample concentration, on average. Concentration differences between runoff and low-flow conditions were not observed, but seasonal differences were observed in atrazine, metolachlor, DEET, and HHCB concentrations. Water quality benchmarks for individual OWCs were exceeded at 20 sites, and at 7 sites benchmarks were exceeded by a factor of 10 or more. The compounds with the most frequent water quality benchmark exceedances were the PAHs benzo[a]pyrene, pyrene, fluoranthene, and anthracene, the detergent metabolite 4-nonylphenol, and the herbicide atrazine. Computed estradiol equivalency quotients (EEQs) using only nonsteroidal endocrine-active compounds indicated medium to high risk of estrogenic effects (intersex or vitellogenin induction) at 10 sites. EEQs at 3 sites were comparable to values reported in effluent. This multifaceted study is the largest, most comprehensive assessment of the

  5. Hydromorphodynamic effects of the width ratio and local tributary widening on discordant confluences

    Science.gov (United States)

    Guillén-Ludeña, S.; Franca, M. J.; Alegria, F.; Schleiss, A. J.; Cardoso, A. H.

    2017-09-01

    River training works performed in the last couple of centuries constrained the natural dynamics of channel networks in locations that include the confluences between tributaries and main channels. As a result, the dynamics of these confluences are currently characterized by homogeneous flow depths, flow velocities, and morphologic conditions, which are associated with impoverished ecosystems. The widening of river reaches is seen as a useful measure for river restoration, as it enhances the heterogeneity in flow depths, flow velocities, sediment transport, and bed substrates. The purpose of this study is to analyze the effects of local widening of the tributary mouth as well as the effects of the ratio between the width of the tributary and that of the main channel on the flow dynamics and bed morphology of river confluences. For that purpose, 12 experiments were conducted in a 70° laboratory confluence. In these experiments, three unit-discharge ratios were tested (qr = 0.37, 0.50, and 0.77) with two width ratios and two tributary configurations. The unit-discharge ratio is defined as the unit discharge in the tributary divided by that of the main channel, measured upstream of the confluence. The width ratio, which is defined as the width of the tributary divided by that of the main channel, was modified by changing the width of the main channel from 0.50 to 1.00 m (corresponding to Br = 0.30 and 0.15 respectively). The tributary configurations consisted of (i) a straight reach with a constant width (the so-called reference configuration) and (ii) a straight reach with a local widening at the downstream end (the so-called widened configuration). During the experiments, a uniform sediment mixture was continuously supplied to both channels. This experimental setup is novel among existing experimental studies on confluence dynamics, as it addresses new confluence configurations and includes a continuous sediment supply to both channels. The experiments were run

  6. The Effect of Number of Storey's and Columns Dimensions on the Accuracy of Tributary Area Method

    Directory of Open Access Journals (Sweden)

    Imad Al-Qasem

    2014-03-01

    Full Text Available In recent years, the utilization of computer techniques in engineering application has become an irreversible trend. This is achieved through using computer as the device for modeling, analysis, and design. The study mainly has focused on the accuracy of the tributary area method for estimation load , as compared to finite element method by SAP2000, considering the effect of building overall height (i.e. number of storey's from 1 to 10 and column dimensions (i.e. stiffness from 20×20 cm to 70×70 cm. According to the analysis of the data obtained, we can see the error in the load computed by the tributary area approximation becomes relatively larger as the number of storey's increases, especially for the lateral load calculations, and the stiffness of the columns increases, the predictions using the tributary area method improves for both axial and lateral forces in the columns.

  7. Generalization of the Sitnica river drainage system with potential pollution of tributaries

    Directory of Open Access Journals (Sweden)

    Valjarević Aleksandar

    2015-01-01

    Full Text Available Maps are miniature graphic representation of distinct area and as not being completely real require generalization. Cartographic generalization represents a specific investigation method in cartography. Generalization includes the processes of selection, simplification, and symbolization of details according to the purpose and the map scale. The river generalization requires the phase classification, selection, magnification and simplification to being used. Linear symbols are given on the map by their corresponding/characteristic length and remained unchanged even after the generalization. Particular cartographic criterions need to be applied during generalization. In the given case of the Sitnica river drainage system were applied the computer supported generalization based on the software Global Mapper 16.1 and the Open source software QGIS 2.6.1. The Sitnica drainage system is generalized in three levels. The first included digitalization of all linear objects related to the river Sitnica and its tributaries. Second level resulted in vector generalized data that indicate on polluted tributaries, whereas the final, third stage led to construction of multilayered vector map of the Sitnica catchments area with polluted tributaries.

  8. Flood potential of Fortymile Wash and its principal southwestern tributaries, Nevada Test Site, Southern Nevada

    International Nuclear Information System (INIS)

    Squires, R.R.; Young, R.L.

    1984-01-01

    Flood hazards for a 9-mile reach of Fortymile Wash and its principal southwestern tributaries - Busted Butte, Drill Hole, and Yucca Washes - were evaluated to aid in determining possible sites for the storage of high-level radioactive wastes on the Nevada Test Site. Data from 12 peak-flow gaging stations adjacent to the Test Site were used to develop regression relations that would permit an estimation of the magnitude of the 100- and 500-year flood peaks (Q 100 and Q 500 ), in cubic feet per second. The resulting equations are: Q 100 = 482A 0 565 and Q 500 = 2200A 0 571 , where A is the tributary drainage area, in square miles. The estimate of the regional maximum flood was based on data from extreme floods elsewhere in Nevada and in surrounding states. Among seven cross sections on Fortymile Wash, the estimated maximum depths of the 100-year, 500-year, and regional maximum floods are 8, 11, and 29 feet, respectively. At these depths, flood water would remain within the deeply incised channel of the wash. Mean flow velocities would be as great as 9, 14, and 28 feet per second for the three respective flood magnitudes. The study shows that Busted Butte and Drill Hole Washes (9 and 11 cross sections, respectively) would have water depths of up to at least 4 feet and mean flow velocities of up to at least 8 feet per second during a 100-year flood. A 500-year flood would exceed stream-channel capacities at several places, with depths to 10 feet and mean flow velocities to 11 feet per second. The regional maximum flood would inundate sizeable areas in central parts of the two watersheds. At Yucca Wash (5 cross sections), the 100-year, 500-year, and regional maximum floods would remain within the stream channel. Maximum flood depths would be about 5, 9, and 23 feet and mean velocities about 9, 12, and 22 feet per second, respectively, for the three floods

  9. Flood potential of Topopah Wash and tributaries, eastern part of Jackass Flats, Nevada Test Site, southern Nevada

    International Nuclear Information System (INIS)

    Christensen, R.C.; Spahr, N.E.

    1980-01-01

    Guidelines for evaluating potential surface facilities to be used for the storage of high-level radioactive wastes on the Nevada Test Site in southern Nevada include the consideration of the potential for flooding. Those floods that are considered to constitute the principal flood hazards for these facilities are the 100- and 500-year floods, and the maximum potential flood. Flood-prone areas for the three floods with present natural-channel conditions were defined for the eastern part of Jackass Flats in the southwestern part of the Nevada Test Site. The 100-year flood-prone areas would closely parallel most stream channels with very few occurrences of out-of-bank flooding between adjacent channels. Out-of-bank flooding would occur at depths of less than 2 feet with mean velocities as much as 7 feet per second. Channel flood depths would range from 1 to 9 feet and mean velocities would range from 3 to 9 feet per second. The 500-year flood would exceed the discharge capacities of all channels except for Topopah Wash and some channels in the upstream reaches of a few tributaries. Out-of-bank flows between adjacent channels would occur at depths as much as 3 feet with mean velocities of more than 7 feet per second. Channel flood depths would range from 1 to 12 feet and mean velocities would range from 3 to 13 feet per second. The maximum potential flood would inundate most of the study area. Excluded areas would be those located immediately east of the upstream reach of Topopah Wash and between upstream channel reaches of some tributaries. Out-of-bank flows between adjacent channels would occur at depths as much as 5 feet with mean velocities as much s 13 feet per second. Channel flood depth would range from 2 to 23 feet and mean velocities would range from 4 to 26 feet per second

  10. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    Long, James M.; Starks, Trevor A.; Farling, Tyler; Bastarache, Robert

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an

  11. Habitat use by juvenile salmonids in Lake Ontario tributaries-species, age, diel and seasonal effects

    Science.gov (United States)

    Johnson, James H.; McKenna, James E.

    2017-01-01

    Understanding the habitat needs of fish and how these requirements may change seasonally over a 24-h period is important, especially for highly managed sport species. Consequently, we examined the diel and seasonal habitat use of four juvenile salmonid species in streams in the Lake Ontario watershed. For juvenile Atlantic salmon Salmo salarand juvenile rainbow trout Oncorhynchus mykiss, differences in day versus night habitat use were more profound than seasonal differences. Observed differences in day versus night habitat for all species and age classes were mainly due to the use of less object oriented cover at night and to a lesser extent to the use of slower velocities and smaller substrate at night. Seasonal differences in habitat use were also observed, likely due to increased fish size, and included movement to deeper and faster water and the use of larger substrate and more cover from summer to winter. Different habitat variables were important to individual species. Juvenile Atlantic salmon were associated with higher water velocities, juvenile rainbow trout with larger substrate and more cover, and subyearling Chinook salmon O. tshawytscha and subyearling coho salmon O. kisutch with small substrate and less cover. Our observations demonstrate that habitat partitioning occurs and likely reduces intraspecific and interspecific competition which may increase the potential production of all four species in sympatry. Consequently, these findings provide important information for resource managers charged with managing, protecting, and enhancing Great Lakes tributaries where all or some of these species occur.

  12. The effect of water level fluctuation on tributary spawning migration of reservoir fish

    Czech Academy of Sciences Publication Activity Database

    Hladík, Milan; Kubečka, Jan

    2004-01-01

    Roč. 4, č. 4 (2004), s. 449-457 ISSN 1642-3593. [Ecohydrology and physical habitat modifications in lakes. Mondsee, 26.11.2003-28.11.2003] R&D Projects: GA ČR(CZ) GA206/02/0520; GA AV ČR(CZ) IBS6017004; GA AV ČR(CZ) IAA6017201; GA AV ČR(CZ) KSK6005114 Institutional research plan: CEZ:AV0Z6017912 Keywords : freshwater fish spawning migration * tributary * reservoir Subject RIV: GL - Fishing

  13. Effects of watershed and in-stream liming on macroinvertebrate communities in acidified tributaries to an Adirondack lake

    Science.gov (United States)

    George, Scott D.; Baldigo, Barry P.; Lawrence, Gregory B.; Fuller, Randall L.

    2018-01-01

    Liming techniques are being explored as a means to accelerate the recovery of aquatic biota from decades of acid deposition in many regions. The preservation or restoration of native sportfish populations has typically been the impetus for liming programs, and as such, less attention has been given to its effects on other biological assemblages such as macroinvertebrates. Furthermore, the differing effects of various lime application strategies such as in-stream and watershed applications are not well understood. In 2012, a program was initiated using in-stream and aerial (whole-watershed) liming to improve water quality and Brook Trout (Salvelinus fontinalis) recruitment in three acidified tributaries of a high-elevation Adirondack lake in New York State. Concurrently, macroinvertebrates were sampled annually between 2013 and 2016 at 3 treated sites and 3 untreated reference sites to assess the effects of each liming technique on this community. Despite improvements in water chemistry in all three limed streams, our results generally suggest that neither liming technique succeeded in improving the condition of macroinvertebrate communities. The watershed application caused an immediate and unsustained decrease in the density of macroinvertebrates and increase in the proportion of sensitive taxa. These changes were driven primarily by a one-year 71 percent reduction of the acid-tolerant Leuctra stoneflies and likely represent an initial chemistry shock from the lime application rather than a recovery response. The in-stream applications appeared to reduce the density of macroinvertebrates, particularly in one stream where undissolved lime covered the natural substrate. The close proximity of our study sites to the in-stream application points (50 and 1230 m) may partly explain these negative effects. Our results are consistent with prior studies of in-stream liming which indicate that this technique often fails to restore macroinvertebrate communities to a pre

  14. Effects of watershed and in-stream liming on macroinvertebrate communities in acidified tributaries to an Adirondack lake

    Science.gov (United States)

    George, Scott D.; Baldigo, Barry P.; Lawrence, Gregory B.; Fuller, Randall L.

    2018-01-01

    Liming techniques are being explored as a means to accelerate the recovery of aquatic biota from decades of acid deposition in many regions. The preservation or restoration of native sportfish populations has typically been the impetus for liming programs, and as such, less attention has been given to its effects on other biological assemblages such as macroinvertebrates. Furthermore, the differing effects of various lime application strategies such as in-stream and watershed applications are not well understood. In 2012, a program was initiated using in-stream and aerial (whole-watershed) liming to improve water quality and Brook Trout (Salvelinus fontinalis) recruitment in three acidified tributaries of a high-elevation Adirondack lake in New York State. Concurrently, macroinvertebrates were sampled annually between 2013 and 2016 at 3 treated sites and 3 untreated reference sites to assess the effects of each liming technique on this community. Despite improvements in water chemistry in all three limed streams, our results generally suggest that neither liming technique succeeded in improving the condition of macroinvertebrate communities. The watershed application caused an immediate and unsustained decrease in the density of macroinvertebrates and increase in the proportion of sensitive taxa. These changes were driven primarily by a one-year 71 percent reduction of the acid-tolerant Leuctra stoneflies and likely represent an initial chemistry shock from the lime application rather than a recovery response. The in-stream applications appeared to reduce the density of macroinvertebrates, particularly in one stream where undissolved lime covered the natural substrate. The close proximity of our study sites to the in-stream application points (50 and 1230 m) may partly explain these negative effects. Our results are consistent with prior studies of in-stream liming which indicate that this technique often fails to restore macroinvertebrate communities to a pre

  15. Effects of coalbed natural gas development on fish assemblages in tributary streams of the Powder and Tongue rivers

    Science.gov (United States)

    Davis, W.N.; Bramblett, R.G.; Zale, A.V.

    2010-01-01

    1. Extraction of coalbed natural gas (CBNG) often results in disposal of large quantities of CBNG product water, which may affect aquatic ecosystems. We evaluated the effects of CBNG development on fish assemblages in tributary streams of the Powder and Tongue rivers. We used treatment and control, impact versus reference sites comparisons, surveys of CBNG product-water streams and in situ fish survival approaches to determine if CBNG development affected fish assemblages.2. Several of our results suggested that CBNG development did not affect fish assemblages. Species richness and index of biotic integrity (IBI) scores were similar in streams with and streams without CBNG development, and overall biotic integrity was not related to the number or density of CBNG wells. Fish occurred in one stream that was composed largely or entirely of CBNG product water. Sentinel fish survived in cages at treatment sites where no or few fish were captured, suggesting that factors such as lack of stream connectivity rather than water quality limited fish abundance at these sites. Fish species richness did not differ significantly from 1994 to 2006 in comparisons of CBNG-developed and undeveloped streams. Biotic integrity declined from 1994 to 2006; however, declines occurred at both impact and reference sites, possibly because of long-term drought.3. Some evidence suggested that CBNG development negatively affected fish assemblages, or may do so over time. Specific conductivity was on average higher in treatment streams and was negatively related to biotic integrity. Four IBI species richness metrics were negatively correlated with the number or density of CBNG wells in the catchment above sampling sites. Bicarbonate, one of the primary ions in product water, was significantly higher in developed streams and may have limited abundance of longnose dace (Rhinichthys cataractae). Total dissolved solids, alkalinity, magnesium and sulphate were significantly higher in developed streams

  16. Pulsed flows, tributary inputs, and food web structure in a highly regulated river

    Science.gov (United States)

    Sabo, John; Caron, Melanie; Doucett, Richard R.; Dibble, Kimberly L.; Ruhi, Albert; Marks, Jane; Hungate, Bruce; Kennedy, Theodore A.

    2018-01-01

    1.Dams disrupt the river continuum, altering hydrology, biodiversity, and energy flow. Although research indicates that tributary inputs have the potential to dilute these effects, knowledge at the food web level is still scarce.2.Here we examined the riverine food web structure of the Colorado River below Glen Canyon Dam, focusing on organic matter sources, trophic diversity, and food chain length. We asked how these components respond to pulsed flows from tributaries following monsoon thunderstorms that seasonally increase streamflow in the American Southwest.3.Tributaries increased the relative importance of terrestrial organic matter, particularly during the wet season below junctures of key tributaries. This contrasted with the algal-based food web present immediately below Glen Canyon Dam.4.Tributary inputs during the monsoon also increased trophic diversity and food chain length: food chain length peaked below the confluence with the largest tributary (by discharge) in Grand Canyon, increasing by >1 trophic level over a 4-5 kilometre reach possibly due to aquatic prey being flushed into the mainstem during heavy rain events.5.Our results illustrate that large tributaries can create seasonal discontinuities, influencing riverine food web structure in terms of allochthony, food web diversity, and food chain length.6.Synthesis and applications. Pulsed flows from unregulated tributaries following seasonal monsoon rains increase the importance of terrestrially-derived organic matter in large, regulated river food webs, increasing food chain length and trophic diversity downstream of tributary inputs. Protecting unregulated tributaries within hydropower cascades may be important if we are to mitigate food web structure alteration due to flow regulation by large dams. This is critical in the light of global hydropower development, especially in megadiverse, developing countries where dam placement (including completed and planned structures) is in tributaries.

  17. Assessing the potential of satellite-based precipitation estimates for flood frequency analysis in ungauged or poorly gauged tributaries of China's Yangtze River basin

    Science.gov (United States)

    Gao, Zhen; Long, Di; Tang, Guoqiang; Zeng, Chao; Huang, Jiesheng; Hong, Yang

    2017-07-01

    Flood frequency analysis (FFA) is critical for water resources engineering projects, particularly the design of hydraulic structures such as dams and reservoirs. However, it is often difficult to implement FFA in ungauged or poorly gauged basins because of the lack of consistent and long-term records of streamflow observations. The objective of this study was to evaluate the utility of satellite-based precipitation estimates for performing FFA in two presumably ungauged tributaries, the Jialing and Tuojiang Rivers, of the upper Yangtze River. Annual peak flow series were simulated using the Coupled Routing and Excess STorage (CREST) hydrologic model. Flood frequency was estimated by fitting the Pearson type III distribution of both observed and modeled streamflow with historic floods. Comparison of satellite-based precipitation products with a ground-based daily precipitation dataset for the period 2002-2014 reveals that 3B42V7 outperformed 3B42RT. The 3B42V7 product also shows consistent reliability in streamflow simulation and FFA (e.g., relative errors -20%-5% in the Jialing River). The results also indicate that complex terrain, drainage area, and reservoir construction are important factors that impact hydrologic model performance. The larger basin (156,736 km2) is more likely to produce satisfactory results than the small basin (19,613 km2) under similar circumstances (e.g., Jialing/Tuojiang calibrated by 3B42V7 for the calibration period: NSCE = 0.71/0.56). Using the same calibrated parameter sets from the entire Jialing River basin, the 3B42V7/3B42RT-driven hydrologic model performs better for two tributaries of the Jialing River (e.g., for the calibration period, NSCE = 0.71/0.60 in the Qujiang River basin and 0.54/0.38 in the Fujiang River basin) than for the upper mainstem of the Jialing River (NSCE = 0.34/0.32), which has more cascaded reservoirs with all these tributaries treated as ungauged basins for model validation. Overall, this study underscores

  18. Chesapeake Bay Tributary Strategies

    Science.gov (United States)

    Chesapeake Bay Tributary Strategies were developed by the seven watershed jurisdictions and outlined the river basin-specific implementation activities to reduce nutrient and sediment pollutant loads from point and nonpoint sources.

  19. Effects of extreme floods on macroinvertebrate assemblages in tributaries to the Mohawk River, New York, USA

    Science.gov (United States)

    Calderon, Mirian R.; Baldigo, Barry P.; Smith, Alexander J.; Endreny, Theodore A.

    2017-01-01

    Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow-monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index-phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region.

  20. Ecological effects of dams, alien fish, and physiochemical environmental factors on homogeneity/heterogeneity of fish community in four tributaries of the Pearl River in China.

    Science.gov (United States)

    Zeng, Lei; Zhou, Lei; Guo, Ding-Li; Fu, Dong-Hua; Xu, Peng; Zeng, Shuang; Tang, Qin-Dong; Chen, An-Luo; Chen, Fei-Qiao; Luo, Yong; Li, Gui-Feng

    2017-06-01

    In this study, we aimed to characterize the fish community structure and identify the drivers contributing to homogenization/differentiation processes in four tributaries to the Pearl River, Guangxi Province, China, over the past few decades. We sampled 22 sites seasonally from 2013 through 2015, and these sites were selected based on archived records of previous sampling conducted in the 1980s. Jaccard's faunal similarity index, cluster analysis, and canonical correspondence analysis (CCA) were applied to describe the homogenization/differentiation of fish community and illustrate the potential effectors. The number of fish species present in three of the four sampled tributaries declined dramatically over the past 30 years, leading toward a trend of increased fish community homogeneity throughout the watershed. Results from multidimensional scaling and cluster analyses allowed us to divide the study area into two distinct ecoregions. Four species ( yellow catfish Pelteobagrus fulvidraco , pond loach Misgurnus anguillicaudatus , Nile tilapia Oreochromis niloticus , and sharpbelly Hemiculter leucisculus ) were considered to be indicative fish species contributing more than 5% of the dissimilarity between the two eco-regions according to the results of similarity percentage procedure. Results from CCA revealed that pH and latitude corresponded with the dominant fish species of each respective tributary. More specifically, CCA results allowed us to classify dominant fish species into three distinct groups. The first group was mainly located in Guijiang characterized by higher latitudes and lower pH values, the second group was widespread in the four tributaries, and the last group was primarily distributed in Yujiang, Youjiang, and Zuojiang characterized by lower latitudes and higher pH values. Spatial differentiation of fish community structure and temporal homogeneity of species composition were attributed to the joint actions of human interventions including

  1. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    James M. Long; Trevor A. Starks; Tyler Farling; Robert. Bastarache

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus...

  2. Effects of coal-mine discharges on the quality of the Stonycreek River and its tributaries, Somerset and Cambria counties, Pennsylvania

    Science.gov (United States)

    Williams, Donald R.; Sams, James I.; Mulkerrin, Mary E.

    1996-01-01

    This report describes the results of a study by the U.S. Geological Survey, done in cooperation with the Somerset Conservation District, to locate and sample abandoned coal-mine discharges in the Stonycreek River Basin, to prioritize the mine discharges for remediation, and to determine the effects of the mine discharges on water quality of the Stonycreek River and its major tributaries. From October 1991 through November 1994, 270 abandoned coal-mine discharges were located and sampled. Discharges from 193 mines exceeded U.S. Environmental Protection Agency effluent standards for pH, discharges from 122 mines exceeded effluent standards for total-iron concentration, and discharges from 141 mines exceeded effluent standards for total-manganese concentration. Discharges from 94 mines exceeded effluent standards for all three constituents. Only 40 mine discharges met effluent standards for pH and concentrations of total iron and total manganese.A prioritization index (PI) was developed to rank the mine discharges with respect to their loading capacity on the receiving stream. The PI lists the most severe mine discharges in a descending order for the Stonycreek River Basin and for subbasins that include the Shade Creek, Paint Creek, Wells Creek, Quemahoning Creek, Oven Run, and Pokeytown Run Basins.Passive-treatment systems that include aerobic wetlands, compost wetlands, and anoxic limestone drains (ALD's) are planned to remediate the abandoned mine discharges. The successive alkalinity-producing-system treatment combines ALD technology with the sulfate reduction mechanism of the compost wetland to effectively remediate mine discharge. The water quality and flow of each mine discharge will determine which treatment system or combination of treatment systems would be necessary for remediation.A network of 37 surface-water sampling sites was established to determine stream-water quality during base flow. A series of illustrations show how water quality in the mainstem

  3. [Effect of Seasonal Temperature Increasing on Nitrogen Mineralization in Soil of the Water Level Fluctuating Zone of Three Gorge Tributary During the Dry Period].

    Science.gov (United States)

    Lin, Jun-jie; Zhang, Shuai; Liu, Dan; Zhou, Bin; Xiao, Xiao-jun; Ma, Hui-yan; Yu, Zhi-guo

    2016-02-15

    To reveal the effect of seasonal temperature increasing on nitrogen mineralization in soil of the water level fluctuating soil zone of three gorge reservoir areas in the Yangtze river tributary during the dry period, surface soils were collected from the water level fluctuating zone of Pengxi river crossing two hydrological sections, i.e., upstream and downstream and three water level altitudes, 155 m (low), 165 m (middle) and 175 m (high). We incubated the soil at 25 degrees C and 35 degrees C to determine the transformation rates of nitrogen in soil of Pengxi river basin during the dry period. The result showed that TN and NO3- -N contents in the soil of upstream section and higher (175 m) altitude of water level were higher than those in downstream and low (165 m) altitude of water level, whereas the pattern for NH4+ -N was different, with higher NH4+ -N contents in downstream and low water level. The inorganic nitrogen was dominated by NO3- -N, which accounted for up to 57.4%-84.7% of inorganic nitrogen. Generally, soil ammoniation, nitration and net N mineralization increased with the rising water level altitude and stream sections (P temperature, (P 0.05).

  4. The Hubble effective potential

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, T.M.; Miao, S.P.; Prokopec, T. [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Leuvenlaan 4, Postbus 80.195, 3508 TD Utrecht (Netherlands); Woodard, R.P., E-mail: T.M.Janssen@uu.nl, E-mail: S.Miao@uu.nl, E-mail: T.Prokopec@uu.nl, E-mail: woodard@phys.ufl.edu [Department of Physics, University of Florida, Gainesville, FL 32611 (United States)

    2009-05-15

    We generalize the effective potential to scalar field configurations which are proportional to the Hubble parameter of a homogeneous and isotropic background geometry. This may be useful in situations for which curvature effects are significant. We evaluate the one loop contribution to the Hubble Effective Potential for a massless scalar with arbitrary conformal and quartic couplings, on a background for which the deceleration parameter is constant. Among other things, we find that inflationary particle production leads to symmetry restoration at late times.

  5. Assessing the link between coastal urbanization and the quality of nekton habitat in mangrove tidal tributaries

    Science.gov (United States)

    Krebs, Justin M.; Bell, Susan S.; McIvor, Carole C.

    2014-01-01

    To assess the potential influence of coastal development on habitat quality for estuarine nekton, we characterized body condition and reproduction for common nekton from tidal tributaries classified as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). We then evaluated these metrics of nekton performance, along with several abundance-based metrics and community structure from a companion paper (Krebs et al. 2013) to determine which metrics best reflected variation in land-use and in-stream habitat among tributaries. Body condition was not significantly different among undeveloped, industrial, and man-made tidal tributaries for six of nine taxa; however, three of those taxa were in significantly better condition in urban compared to undeveloped tributaries. Palaemonetes shrimp were the only taxon in significantly poorer condition in urban tributaries. For Poecilia latipinna, there was no difference in body condition (length–weight) between undeveloped and urban tributaries, but energetic condition was significantly better in urban tributaries. Reproductive output was reduced for both P. latipinna (i.e., fecundity) and grass shrimp (i.e., very low densities, few ovigerous females) in urban tributaries; however a tradeoff between fecundity and offspring size confounded meaningful interpretation of reproduction among land-use classes for P. latipinna. Reproductive allotment by P. latipinna did not differ significantly among land-use classes. Canonical correspondence analysis differentiated urban and non-urban tributaries based on greater impervious surface, less natural mangrove shoreline, higher frequency of hypoxia and lower, more variable salinities in urban tributaries. These characteristics explained 36 % of the variation in nekton performance, including high densities of poeciliid fishes, greater energetic condition of sailfin mollies, and low densities of several common nekton and economically important taxa from urban tributaries

  6. Tributaries as richness source for Oligochaeta assemblage (Annelida of Neotropical dammed river

    Directory of Open Access Journals (Sweden)

    FH Ragonha

    Full Text Available Tributaries may serve as richness source for the river main channel and the zoobenthos community is a good tool to verify this kind of pattern. In this study, we aimed to characterize the benthic invertebrate assemblage in three tributaries associated to the Paraná River main channel, focusing in Oligochaeta community. We hypothesized that (i in tributaries, Oligochaeta are richer than the main river (Paraná River and (ii dammed tributary (Paranapanema River is poorly diverse than the others. Samples were conducted in Paranapanema, Baía and Ivinhema tributaries using a modified Petersen grab along three transects (samples conducted inside the tributary, in the mouth of each tributary and inside Paraná River. To analyze (i the difference between the richness and density among the tributaries and the Paraná River and (ii effect of each tributary transect on the Oligochaeta richness we used a nonparametric Kruskal-Wallis test. Changes in environmental variables and in richness and composition of Oligochaeta were summarized by Canonic Correspondence Analysis. It was registered 21 different benthic invertebrates taxa, being Oligochaeta assemblage with the highest density. Within Oligochaeta, Narapa bonettoi was the most abundant species, followed by Haplotaxis aedochaeta and Paranadrilus descolei. In our results we refused both hypotheses, because we did not found significant differences for richness and density between the tributaries and the main river, and also no difference between the three transects of each tributary were found. However, the tributaries less influenced by damming, especially the Baía recorded high richness. This corroborates their importance to diversity in the floodplain and the species of Oligochaeta reflect the peculiar characteristics of habitats within each tributaries.

  7. The effective nuclear potential

    International Nuclear Information System (INIS)

    Skyrme, T.H.R.

    1994-01-01

    An empirical analyses is made of the mean effective internucleon potential required in the shell-model description of nuclei, allowing for the presence of many-body effects as suggested by current theory. A consistent description is found in which the effective two-body interaction acts almost entirely in even states, and the many-body effects are simulated by a repulsive three-body contact interaction. The strength of the two-body interaction is consistent with that expressed by the free scattering matrix of the two-nucleon system, and that of the three-body interaction with the 'rearrangement energy' calculated in the many-body theory. (author). 21 refs, 2 figs, 7 tabs

  8. Effective potential for non-convex potentials

    International Nuclear Information System (INIS)

    Fujimoto, Y.; O'Raifeartaigh, L.; Parravicini, G.

    1983-01-01

    It is shown that the well-known relationship between the effective potential GAMMA and the vacuum graphs μ of scalar QFT follows directly from the translational invariance of the measure, and that it holds for all values of the fields phi if, and only if, the classical potential is convex. In the non-convex case μ appears to become complex for some values of phi, but it is shown that the complexity is only apparent and is due to the failure of the loop expansion. The effective potential actually remains real and well-defined for all phi, and reduces to μ in the neighbourhood of the classical minima. A number of examples are considered, notably potentials which are spontaneously broken. In particular the mechanism by which a spontaneous breakdown may be generated by radiative corrections is re-investigated and some new insights obtained. Finally, it is shown that the renormalization group equations for the parameters may be obtained by inspection from the effective potential, and among the examples considered are SU(n) fields and supermultiplets. In particular, it is shown that for supermultiplets the effective potential is not only real but positive. (orig.)

  9. Tributaries affect the thermal response of lakes to climate change

    Science.gov (United States)

    Råman Vinnå, Love; Wüest, Alfred; Zappa, Massimiliano; Fink, Gabriel; Bouffard, Damien

    2018-01-01

    Thermal responses of inland waters to climate change varies on global and regional scales. The extent of warming is determined by system-specific characteristics such as fluvial input. Here we examine the impact of ongoing climate change on two alpine tributaries, the Aare River and the Rhône River, and their respective downstream peri-alpine lakes: Lake Biel and Lake Geneva. We propagate regional atmospheric temperature effects into river discharge projections. These, together with anthropogenic heat sources, are in turn incorporated into simple and efficient deterministic models that predict future water temperatures, river-borne suspended sediment concentration (SSC), lake stratification and river intrusion depth/volume in the lakes. Climate-induced shifts in river discharge regimes, including seasonal flow variations, act as positive and negative feedbacks in influencing river water temperature and SSC. Differences in temperature and heating regimes between rivers and lakes in turn result in large seasonal shifts in warming of downstream lakes. The extent of this repressive effect on warming is controlled by the lakes hydraulic residence time. Previous studies suggest that climate change will diminish deep-water oxygen renewal in lakes. We find that climate-related seasonal variations in river temperatures and SSC shift deep penetrating river intrusions from summer towards winter. Thus potentially counteracting the otherwise negative effects associated with climate change on deep-water oxygen content. Our findings provide a template for evaluating the response of similar hydrologic systems to on-going climate change.

  10. Tributaries affect the thermal response of lakes to climate change

    Directory of Open Access Journals (Sweden)

    L. Råman Vinnå

    2018-01-01

    Full Text Available Thermal responses of inland waters to climate change varies on global and regional scales. The extent of warming is determined by system-specific characteristics such as fluvial input. Here we examine the impact of ongoing climate change on two alpine tributaries, the Aare River and the Rhône River, and their respective downstream peri-alpine lakes: Lake Biel and Lake Geneva. We propagate regional atmospheric temperature effects into river discharge projections. These, together with anthropogenic heat sources, are in turn incorporated into simple and efficient deterministic models that predict future water temperatures, river-borne suspended sediment concentration (SSC, lake stratification and river intrusion depth/volume in the lakes. Climate-induced shifts in river discharge regimes, including seasonal flow variations, act as positive and negative feedbacks in influencing river water temperature and SSC. Differences in temperature and heating regimes between rivers and lakes in turn result in large seasonal shifts in warming of downstream lakes. The extent of this repressive effect on warming is controlled by the lakes hydraulic residence time. Previous studies suggest that climate change will diminish deep-water oxygen renewal in lakes. We find that climate-related seasonal variations in river temperatures and SSC shift deep penetrating river intrusions from summer towards winter. Thus potentially counteracting the otherwise negative effects associated with climate change on deep-water oxygen content. Our findings provide a template for evaluating the response of similar hydrologic systems to on-going climate change.

  11. Tributaries affect the thermal response of lakes to climate change

    OpenAIRE

    L. Råman Vinnå; A. Wüest; A. Wüest; M. Zappa; G. Fink; D. Bouffard; D. Bouffard

    2018-01-01

    Thermal responses of inland waters to climate change varies on global and regional scales. The extent of warming is determined by system-specific characteristics such as fluvial input. Here we examine the impact of ongoing climate change on two alpine tributaries, the Aare River and the Rhône River, and their respective downstream peri-alpine lakes: Lake Biel and Lake Geneva. We propagate regional atmospheric temperature effects into river discharge projections. These, toget...

  12. Effective potentials for twisted fields

    International Nuclear Information System (INIS)

    Banach, R.

    1981-01-01

    Minus the density of the effective action, evaluated at the lowest eigenfunction of the (space-time) derivative part of the second (functional) derivative of the classical action, is proposed as a generalised definition of the effective potential, applicable to twisted as well as untwisted sectors of a field theory. The proposal is corroborated by several specific calculations in the twisted sector, namely phi 4 theory (real and complex) and wrong-sign-Gordon theory, in an Einstein cylinder, where the exact integrability of the static solutions confirms the effective potential predictions. Both models exhibit a phase transition, which the effective potential locates, and the one-loop quantum shift in the critical radius is computed for the real phi 4 model, being a universal result. Topological mass generation at the classical level is pointed out, and the exactness of the classical effective potential approximation for complex phi 4 is discussed. (author)

  13. Estuarine Sediment Budgets for Chesapeake Bay Tributaries

    Science.gov (United States)

    2012-09-01

    2003. Estuarine sediment sources: A Summary Report of Sediment Processes in Chesapeake Bay and Watershed . Water-Resources Investigations Report 03...2007. Sources and transport of sediment in the watershed : Synthesis of US Geological Survey science for the Chesapeake Bay ecosystem and...originator. Estuarine Sediment Budgets for Chesapeake Bay Tributaries by Julie D. Herman PURPOSE. This Coastal and Hydraulics Engineering

  14. The scales of variability of stream fish assemblage at tributary confluences

    Directory of Open Access Journals (Sweden)

    István Czeglédi

    2015-12-01

    Full Text Available Tributary confluences play an important role in the dispersal of organisms, and consequently, in shaping regional scale diversity in stream networks. Despite their importance in dispersal processes, little is known about how ecological assemblages are organized in these habitats. We studied the scales of variability of stream fish assemblages over three seasons using a hierarchical sampling design, which incorporated three tributaries, three sites at the mouth of each tributary and using four sampling units at each site. We found strong scale dependent variability in species richness, composition and relative abundance. Most of the variation was accounted for by the interactive effect of season, between stream and between site effects, while habitat structure of the sampling units had a relatively minor role. Species richness showed a continuous decrease from the mainstem river in most cases, while species composition and relative abundance changed less consistently along the longitudinal profile. Consequently, we found that not only the junctions presented a strong filter on the species pool, but some species were filtered out if they passed this critical habitat bottleneck. Spatial position of the tributaries along the river also contributed to assemblage variability in the confluences. Overall, our results suggest high variability in fish assemblages across multiple scales at tributary confluences. Environmental management should take a more critical care on the filtering role of tributary confluences in species dispersal, for better understanding patterns and processes in the branches of dendritic stream networks.

  15. Effects of a diversion hydropower facility on the hydrological regime of the Correntes River, a tributary to the Pantanal floodplain, Brazil

    Science.gov (United States)

    Fantin-Cruz, Ibraim; Pedrollo, Olavo; Girard, Pierre; Zeilhofer, Peter; Hamilton, Stephen K.

    2015-12-01

    Facilities that produce hydroelectricity by diversion of part of the river's flow, which are often considered to have lower environmental impact than conventional hydropower dams, are being built in large numbers on river systems throughout the world, yet their cumulative impacts are not well understood. This study evaluated the hydrological effects of operation of a diversion hydropower facility on the Correntes River in Brazil (mean discharge 73 m3 s-1), which is potentially important because of the ecological implications for the floodplains of the Pantanal into which it flows. Many similar dams are built or proposed on rivers feeding the Pantanal. The 210-MW facility known as Ponte de Pedra diverts part of the river flow into a diversion channel in a nearly "run-of-river" design. The natural (reconstructed) and regulated (observed) flow regimes were characterized using Indicators of Hydrologic Alteration (IHA) and Flow Duration Curves (FDC). Seven parameters of IHA were significantly altered by the reservoir formation (magnitude of lowest monthly flow, minimum flows of 1, 3 and 7 days, maximum flow of 90 days and counts of high and low pulses). Among these, Principal Components Analysis identified the maximum flow of 90 days and the count of high flow pulses as integrators of hydrological alterations. The FDC showed that the reservoir also changed the seasonal regime of the flows, with greater changes in the lowest flow season. The reduction of river-floodplain connectivity and loss of associated ecosystem services are the major downstream ecological implications of this altered flow regime. To maintain the seasonal flooding regime while meeting the requirements for hydroelectric production, proposed limits for flow regime alterations are up to ±18% in low flow, ±24% in the rising limb and ±22% in high flow and the falling limb, relative to the natural flow. Operational changes to maintain flows with these limits could easily be implemented because the

  16. Xenoestrogens in the River Elbe and its tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Stachel, Burkhard; Ehrhorn, Ute; Heemken, Olaf-Peter; Lepom, Peter; Reincke, Heinrich; Sawal, Georg; Theobald, Norbert

    2003-08-01

    High concentrations of organic chemicals in the River Elbe may be detrimental to aquatic organisms. - 4-Alkylphenols, 4-alkylphenol ethoxylates, 4-alkylphenoxy carboxylates, bisphenol A, bisphenol F, 4-hydroxyacetophenon, 4-hydroxybenzoic acid and steroid hormones were analyzed in water samples of the River Elbe and its tributaries Schwarze Elster, Mulde, Saale, Havel and Schwinge. Additionally, freshly deposited sediments (FDS, composite samples) of the River Elbe and its tributaries were analyzed. The concentrations in water samples ranged from (in ng/l): bisphenol A 4 to 92, branched nonylphenol 13 to 87, branched nonylphenol ethoxylates <0.5 to 120, 4-tert. nonylphenoxy carboxylates <10 to 940 and 4-hydroxybenzoic acid 4 to 12. Steroid hormones were only detected in the Czech tributaries Jizera and Vltava in concentrations near the limit of quantification. In FDS samples the concentrations amounted to (in {mu}g/kg d.w.): bisphenol A 10-380, branched nonylphenol 27-430, branched nonylphenol ethoxylates 24-3700, nonylphenoxy carboxylates <50 and 4-hydroxybenzoic acid 23-4400. Increased bisphenol A concentrations were found in water and FDS samples taken from the Czech-German border at Schmilka and the mouth of the Schwinge (only water sample). According to studies conducted in the Elbe Estuary and the German Bight, the River Elbe must be considered as a major source of pollution for the North Sea in respect of the compounds analyzed. A comparison of bisphenol A concentrations, 4-alkylphenols and the corresponding ethoxylates analyzed in the River Elbe and its tributaries with those found in other German surface waters indicated a low level of contamination. The evaluation of the data based on LOEC-values indicated that the concentrations were well below the effectivity threshold for some 4-alkylphenols. According to recent ecotoxicological investigations, for example, with prosobranch snails, bisphenol A concentrations found in water samples of the River Elbe and

  17. Xenoestrogens in the River Elbe and its tributaries

    International Nuclear Information System (INIS)

    Stachel, Burkhard; Ehrhorn, Ute; Heemken, Olaf-Peter; Lepom, Peter; Reincke, Heinrich; Sawal, Georg; Theobald, Norbert

    2003-01-01

    High concentrations of organic chemicals in the River Elbe may be detrimental to aquatic organisms. - 4-Alkylphenols, 4-alkylphenol ethoxylates, 4-alkylphenoxy carboxylates, bisphenol A, bisphenol F, 4-hydroxyacetophenon, 4-hydroxybenzoic acid and steroid hormones were analyzed in water samples of the River Elbe and its tributaries Schwarze Elster, Mulde, Saale, Havel and Schwinge. Additionally, freshly deposited sediments (FDS, composite samples) of the River Elbe and its tributaries were analyzed. The concentrations in water samples ranged from (in ng/l): bisphenol A 4 to 92, branched nonylphenol 13 to 87, branched nonylphenol ethoxylates <0.5 to 120, 4-tert. nonylphenoxy carboxylates <10 to 940 and 4-hydroxybenzoic acid 4 to 12. Steroid hormones were only detected in the Czech tributaries Jizera and Vltava in concentrations near the limit of quantification. In FDS samples the concentrations amounted to (in μg/kg d.w.): bisphenol A 10-380, branched nonylphenol 27-430, branched nonylphenol ethoxylates 24-3700, nonylphenoxy carboxylates <50 and 4-hydroxybenzoic acid 23-4400. Increased bisphenol A concentrations were found in water and FDS samples taken from the Czech-German border at Schmilka and the mouth of the Schwinge (only water sample). According to studies conducted in the Elbe Estuary and the German Bight, the River Elbe must be considered as a major source of pollution for the North Sea in respect of the compounds analyzed. A comparison of bisphenol A concentrations, 4-alkylphenols and the corresponding ethoxylates analyzed in the River Elbe and its tributaries with those found in other German surface waters indicated a low level of contamination. The evaluation of the data based on LOEC-values indicated that the concentrations were well below the effectivity threshold for some 4-alkylphenols. According to recent ecotoxicological investigations, for example, with prosobranch snails, bisphenol A concentrations found in water samples of the River Elbe and

  18. Nekton community structure varies in response to coastal urbanization near mangrove tidal tributaries

    Science.gov (United States)

    Krebs, Justin M.; McIvor, Carole C.; Bell, Susan S.

    2014-01-01

    To assess the potential influence of coastal development on estuarine-habitat quality, we characterized land use and the intensity of land development surrounding small tidal tributaries in Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban, or man-made (i.e., mosquito-control ditches). Over one third (37 %) of the tributaries have been heavily developed based on landscape development intensity (LDI) index values >5.0, while fewer than one third (28 %) remain relatively undeveloped (LDI < 3.0). We then examined the nekton community from 11 tributaries in watersheds representing the four defined land-use classes. Whereas mean nekton density was independent of land use, species richness and nekton-community structure were significantly different between urban and non-urban (i.e., undeveloped, industrial, man-made) tributaries. In urban creeks, the community was species-poor and dominated by high densities of poeciliid fishes, Poecilia latipinna and Gambusia holbrooki, while typically dominant estuarine taxa including Menidia spp., Fundulus grandis, and Adinia xenica were in low abundance and palaemonid grass shrimp were nearly absent. Densities of economically important taxa in urban creeks were only half that observed in five of the six undeveloped or industrial creeks, but were similar to those observed in mosquito ditches suggesting that habitat quality in urban and mosquito-ditch tributaries is suboptimal compared to undeveloped tidal creeks. Furthermore, five of nine common taxa were rarely collected in urban creeks. Our results suggest that urban development in coastal areas has the potential to alter the quality of habitat for nekton in small tidal tributaries as reflected by variation in the nekton community.

  19. CHEMICAL COMPOSITION FROM THE DNIESTER RIVER TRIBUTARIES

    Directory of Open Access Journals (Sweden)

    V. Gladchi

    2013-06-01

    Full Text Available This article presents the results obtained in the framework of the project 09.832.08.06A. The role of the tributaries on formation of the Dniester river water and the study of the waters quality of sources / fountains in the catchment area of the Dniester river as sources of water supply and for irrigation in the State Program, Scientific Researches and of the management of waters quality.

  20. Ground-water flow and simulated effects of development in Paradise Valley, a basin tributary to the Humboldt River in Humboldt County, Nevada

    Science.gov (United States)

    Prudic, David E.; Herman, M.E.

    1996-01-01

    A computer model was used to characterize ground-water flow in Paradise Valley, Nevada, and to evaluate probable long-term effects of five hypothetical development scenarios. One finding of the study is that concentrating pumping at the south end of Paradise Valley may increase underflow from the adjacent Humboldt River valley, and might affect flow in the river.

  1. How effective is the effective potential?

    International Nuclear Information System (INIS)

    Dodelson, S.; Gradwohl, B.A.

    1993-01-01

    Motivated by bubble nucleation in first order phase transitions, we question the validity of the effective potential for inhomogeneous configurations. In an attempt to get some insight into the importance of derivative terms, we analyze a simple model, a kink in 1+1 dimensions and zero temperature. We evaluate the energy shift from the quantum fluctuations about the non-uniform background (i.e. the effective action) and compare it to the energy from the effective potential. Our results clearly show that for inhomogeneous configurations it may be inadequate to omit derivative terms and confine oneself to the effective potential. We then couple the kink field to an additional scalar field and perform the same comparison. The addition of the second field allows us to vary the mass of the fluctuations and their coupling to the underlying kink. If the mass of the second field is large, it does not feel the inhomogeneities in the kink field and consequently does not give rise to important derivative corrections in the effective action. In contrast, if the mass is small, derivative terms are significant and the effective potential fails. In the latter regime we can, however, rely on the Born approximation to calculate the effective action. (orig.)

  2. Effects of water temperature on breeding phenology, growth and timing of metamorphosis of foothill yellow-legged frogs (Rana boylii) on the mainstem and selected tributaries of California's Trinity River - 2004-2009.

    Science.gov (United States)

    Clara Wheeler; James Bettaso; Donald Ashton; Hartwell Welsh

    2013-01-01

    The cold temperatures maintained in the Trinity River are beneficial to fish but may be problematic for foothill yellow-legged frogs. We examined the timing of breeding, reproductive output, and growth and development of tadpoles for populations of foothill yellow-legged frogs on the mainstem and six tributaries of the Trinity River. On the colder mainstem, onset of...

  3. Genotoxic effects and gene expression in Danio rerio (Hamilton 1822) (Cypriniformes: Cyprinidae) exposed to mining-impacted tributaries in Manizales, Colombia.

    Science.gov (United States)

    Ossa-López, Paula A; Castaño-Villa, Gabriel J; Rivera-Páez, Fredy A

    2017-09-25

    The zebrafish (Danio rerio) is one of the most studied aquatic organisms for water biomonitoring, due to its sensitivity to environmental degradation and resistance to toxic substances. This study determined the presence of micronuclei and nuclear abnormalities in peripheral blood erythrocytes, and assessed the gene expression of caspase-3 (CASP-3) and metallothionein 1 (MT-1) in the gills and liver of D. rerio. The study fish (n = 45) were exposed to water collected from two stations with mining impact (E2 and E3) and a reference station without evident mining contamination (E1), all located in La Elvira stream (Manizales-Colombia). In addition, a positive control (PC) with HgCl 2 (50 μg/L) and negative control (NC) with tap water were included. The fish from the PC and E2 and E3 treatments displayed genotoxic effects and changes in gene expression, with significant differences in micronuclei formation and the presence of blebbed nuclei. The cytochrome oxidase subunit I (COI) gene was used as reference and proved to be stable compared to the β-actin and 28S ribosomal RNA (28S) genes. In gills, CASP-3 expression was higher in the PC, and MT-1 expression was higher in the PC and E3 treatment. In liver, CASP-3 was expressed in the E2 treatment, and MT-1 expression was low. These results show that the genotoxic effects and differential gene expression observed in fish exposed to water from La Elvira stream could also be affecting the organisms present in this habitat.

  4. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: II. Biological consequences of exposure

    Science.gov (United States)

    Brigham, Mark E.; Choy, Steven J.; Moore, Jeremy N.; Banda, Jo A.; Gefell, Daniel J.; Minarik, Thomas A.

    2017-01-01

    The Laurentian Great Lakes contain one fifth of the world’s surface freshwater and have been impacted by human activity since the Industrial Revolution. In addition to legacy contaminants, nitrification and invasive species, this aquatic ecosystem is also the recipient of Contaminants of Emerging Concern (CECs) with poorly understood biological consequences. In the current study, we documented the presence, concentrations, and biological effects of CECs across 27 field sites in six Great Lakes tributaries by examining over 2250 resident and caged sunfish (Lepomis ssp.) for a variety of morphological and physiological endpoints and related these results to CEC occurrence. CEC were ubiquitous across studies sites and their presence and concentrations in water and sediment were highest in effluent dominated rivers and downstream of municipal wastewater treatment plant discharges. However, even putative upstream reference sites were not free of CEC presence and fish at these sites exhibited biological effects consistent with CEC exposure. Only the Fox River exhibited consistent adverse biological effects, including increased relative liver size, greater prominence of hepatocyte vacuoles and increased plasma glucose concentrations. Canonical Redundancy Analysis revealed consistent patterns of biological consequences of CEC exposure across all six tributaries. Increasing plasma glucose concentrations, likely as a result of pollutant-induced metabolic stress, were associated with increased relative liver size and greater prominence of hepatocyte vacuoles. These indicators of pollutant exposure were inversely correlated with indicators of reproductive potential including smaller gonad size and less mature gametes. The current study highlights the need for greater integration of chemical and biological studies and suggests that CECs in the Laurentian Great Lakes Basin may adversely affect the reproductive potential of exposed fish populations. PMID:28953953

  5. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: II. Biological consequences of exposure

    Science.gov (United States)

    Thomas, Linnea M.; Jorgenson, Zachary G.; Brigham, Mark E.; Choy, Steven J.; Moore, Jeremy N.; Banda, Jo A.; Gefell, D.J.; Minarik, Thomas A.; Schoenfuss, Heiko L.

    2017-01-01

    The Laurentian Great Lakes contain one fifth of the world’s surface freshwater and have been impacted by human activity since the Industrial Revolution. In addition to legacy contaminants, nitrification and invasive species, this aquatic ecosystem is also the recipient of Contaminants of Emerging Concern (CECs) with poorly understood biological consequences. In the current study, we documented the presence, concentrations, and biological effects of CECs across 27 field sites in six Great Lakes tributaries by examining over 2250 resident and caged sunfish (Lepomis ssp.) for a variety of morphological and physiological endpoints and related these results to CEC occurrence. CEC were ubiquitous across studies sites and their presence and concentrations in water and sediment were highest in effluent dominated rivers and downstream of municipal wastewater treatment plant discharges. However, even putative upstream reference sites were not free of CEC presence and fish at these sites exhibited biological effects consistent with CEC exposure. Only the Fox River exhibited consistent adverse biological effects, including increased relative liver size, greater prominence of hepatocyte vacuoles and increased plasma glucose concentrations. Canonical Redundancy Analysis revealed consistent patterns of biological consequences of CEC exposure across all six tributaries. Increasing plasma glucose concentrations, likely as a result of pollutant-induced metabolic stress, were associated with increased relative liver size and greater prominence of hepatocyte vacuoles. These indicators of pollutant exposure were inversely correlated with indicators of reproductive potential including smaller gonad size and less mature gametes. The current study highlights the need for greater integration of chemical and biological studies and suggests that CECs in the Laurentian Great Lakes Basin may adversely affect the reproductive potential of exposed fish populations.

  6. Invertebrates as indicators for chemical stress in sewage-influenced stream systems: toxic and endocrine effects in gammarids and reactions at the community level in two tributaries of Lake Constance, Schussen and Argen.

    Science.gov (United States)

    Peschke, Katharina; Geburzi, Jonas; Köhler, Heinz-R; Wurm, Karl; Triebskorn, Rita

    2014-08-01

    The present study investigates the impact of releases from waste water treatment plants and storm water overflow basins on gammarids and other macrozoobenthos. The study relates to a recent upgrading of a waste water treatment plant (Langwiese) at the Schussen river, an important tributary to Lake Constance. Samples were taken at different sites at the Schussen river upstream and downstream of a storm water overflow basin and the waste water treatment plant Langwiese and, in parallel, at the Argen river, a less polluted reference stream. We assessed the influence of water quality on the distribution of macrozoobenthos and on the health of gammarid populations by a variety of ecotoxicological methods including biomarkers prior to the expansion of the waste water treatment plant. Through histopathological studies, the impact of parasites on host tissue health was evaluated. Analyses of heat shock protein (hsp70) levels allowed us to draw conclusions about the proteotoxicity-related stress status of the organisms. Furthermore, gammarid populations from all sites were investigated in respect to sex ratio, parasitism rate, and fecundity. Macrozoobenthos community integrity was determined by means of the saprobic index and the abundance as well as by the number of taxa. In gammarids, the sex ratio was significantly shifted towards females, fecundity was significantly decreased, and the hsp70 level was significantly increased downstream of the waste water treatment plant Langwiese, compared to the upstream sampling site. Similarly, these effects could be detected downstream of three small storm water overflow basins. In the macrozoobenthos communities, the abundance of taxa, the number of taxa, the number of ephemeroptera, plecoptera, and trichoptera taxa (EPT-taxa), and the number of sensitive taxa decreased downstream of the storm water overflow basin Mariatal as well as downstream of the waste water treatment plant Langwiese. Our study showed, that waste water

  7. The effective crystal field potential

    CERN Document Server

    Mulak, J

    2000-01-01

    As it results from the very nature of things, the spherical symmetry of the surrounding of a site in a crystal lattice or an atom in a molecule can never occur. Therefore, the eigenfunctions and eigenvalues of any bound ion or atom have to differ from those of spherically symmetric respective free ions. In this way, the most simplified concept of the crystal field effect or ligand field effect in the case of individual molecules can be introduced. The conventional notion of the crystal field potential is narrowed to its non-spherical part only through ignoring the dominating spherical part which produces only a uniform energy shift of gravity centres of the free ion terms. It is well understood that the non-spherical part of the effective potential "seen" by open-shell electrons localized on a metal ion plays an essential role in most observed properties. Light adsorption, electron paramagnetic resonance, inelastic neutron scattering and basic characteristics derived from magnetic and thermal measurements, ar...

  8. That mighty pantun river and its tributaries

    Directory of Open Access Journals (Sweden)

    Ding Choo Ming

    2010-04-01

    Full Text Available Known as pantun to the Malays in Brunei, Malaysia, Pattani, Riau, Singapore, and Southern Phillipines, it is called peparikan to the Javanese, sesindiran to the Sundanese and many other different names in different ethnic groups in the different parts of the Indo-Malay world, which is made up of Brunei, Indonesia, Malaysia, Singapore, Pattani in southern Thailand, and Mindanao in the southern Philippines. In almost every settlement that sprang up along the major rivers and tributaries in the Indo-Malay world, the pantun blend well with their natural and cultural surroundings. In this article, the geographical extent of the pantun family in the Indo-Malay world is likened to a mighty river that has a complex network of tributaries all over the Indo-Malay world. Within the Indo-Malay world, it is the movement of the peoples help the spread of pantun from one area to the other and makes it an art form of immensely rich and intricate as can be seen from the examples given.

  9. 33 CFR 117.591 - Charles River and its tributaries.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Charles River and its tributaries... BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.591 Charles River and its tributaries. (a) The following requirements apply to all bridges across the Charles River and it's...

  10. Which tributaries disrupt downstream fining along gravel-bed rivers?

    Science.gov (United States)

    Rice, Stephen

    1998-02-01

    Tributaries and other lateral sediment sources can have a significant impact on river bed sediment texture and, in turn, on channel form. Sufficiently voluminous or distinct sediment inputs redefine the mainstem grain-size distribution, punctuating downstream maturation and isolating a sequence of discrete sedimentary links. Within these links fining processes usually dominate, such that models of sorting and abrasion, when applied to individual links, provide reasonable predictions of grain-size change. Links represent the fundamental natural unit within which fining models can be tested, developed and applied. Identification of significant lateral sources is therefore important, yet, beyond vague references to relative tributary size, sediment load, and sediment calibre, no criteria exist for the a priori discrimination of such sources. In this paper a procedure for identifying significant lateral (tributary) sources, without the benefit of grain-size information, is outlined. A high-resolution characterisation of bed material texture along two Canadian gravel-bed rivers facilitated classification of all their perennial tributaries as either significant or insignificant. Three absolute tributary basin parameters and their relative counterparts, chosen to reflect the likely controls on tributary significance, are then used to develop a discriminant function which isolates a large proportion of significant tributaries while minimising incorrect classifications. Examination of consistently misclassified (anomalous) tributaries reveals the importance of lateral source spacing and of inconsistencies in the geomorphic history of the contributing basins. In turn, a general tributary categorisation procedure is suggested which includes a logistic regression model for attaching probability statements to individual classifications. The generality of the discriminant and logistic functions cannot be assessed because of the lack of other suitable data sets.

  11. Water Quality in Tortum Stream and its Tributaries (Erzurum/Turkey

    Directory of Open Access Journals (Sweden)

    Mine KÖKTÜRK

    2015-04-01

    Full Text Available This study was undertaken with the aim of determining the effects of domestic waste and hydroelectric dams on water quality in the Tortum Stream and its tributaries. Water samples were taken monthly from nine sampling points of Tortum Stream and its tributaries between July 2012 and May 2013. Analyzed for temperature (°C, pH, dissolved oxygen (DO, total suspended solids (TSS, alkalinity, Ca, total hardness, sulfate (SO4, ammonia-nitrogen (N-NH3−, nitrite-nitrogen (N-NO2− and nitrate nitrogen (N-NO3− as well as total phosphorus (TP, total orthophosphate (TO, total iron and silica (SiO2 were carried out. Physical and chemical characteristics of Tortum Stream and its tributaries which were examined according to the Water Framework Directive and the Water Pollution Control Regulations. It can be said that the stream has a low water quality standard except for water temperature, dissolved oxygen and sulfate. The results showed that Tortum Stream and tributaries are under threat because of domestic waste, fertilizers and hydroelectric constructions.

  12. Suspended-sediment trapping in the tidal reach of an estuarine tributary channel

    Science.gov (United States)

    Downing-Kunz, Maureen; Schoellhamer, David H.

    2015-01-01

    Evidence of decreasing sediment supply to estuaries and coastal oceans worldwide illustrates the need for accurate and updated estimates. In the San Francisco Estuary (Estuary), recent research suggests a decrease in supply from its largest tributaries, implying the increasing role of smaller, local tributaries in sediment supply to this estuary. Common techniques for estimating supply from tributaries are based on gages located above head of tide, which do not account for trapping processes within the tidal reach. We investigated the effect of a tidal reach on suspended-sediment discharge for Corte Madera Creek, a small tributary of the Estuary. Discharge of water (Q) and suspended-sediment (SSD) were observed for 3 years at two locations along the creek: upstream of tidal influence and at the mouth. Comparison of upstream and mouth gages showed nearly 50 % trapping of upstream SSD input within the tidal reach over this period. At the storm time scale, suspended-sediment trapping efficiency varied greatly (range −31 to 93 %); storms were classified as low- or high-yield based on upstream SSD. As upstream peak Q increased, high-yield storms exhibited significantly decreased trapping. Tidal conditions at the mouth—ebb duration and peak ebb velocity—during storms had a minor effect on sediment trapping, suggesting fluvial processes dominate. Comparison of characteristic fluvial and tidal discharges at the storm time scale demonstrated longitudinal differences in the regulating process for SSD. These results suggest that SSD from gages situated above head of tide overestimate sediment supply to the open waters beyond tributary mouths and thus trapping processes within the tidal reach should be considered.

  13. 46 CFR 7.50 - Chesapeake Bay and tributaries.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Chesapeake Bay and tributaries. 7.50 Section 7.50... Atlantic Coast § 7.50 Chesapeake Bay and tributaries. A line drawn from Cape Charles Light to latitude 36... latitude 36°54.8′ N. longitude 75°55.6′ W. (Chesapeake Bay Entrance Lighted Bell Buoy “CBC”); thence to...

  14. Standard Model Effective Potential from Trace Anomalies

    Directory of Open Access Journals (Sweden)

    Renata Jora

    2018-01-01

    Full Text Available By analogy with the low energy QCD effective linear sigma model, we construct a standard model effective potential based entirely on the requirement that the tree level and quantum level trace anomalies must be satisfied. We discuss a particular realization of this potential in connection with the Higgs boson mass and Higgs boson effective couplings to two photons and two gluons. We find that this kind of potential may describe well the known phenomenology of the Higgs boson.

  15. Interatomic Potentials via the Effective Action Formalism

    Science.gov (United States)

    Rasamny, M.; Valiev, M.; Fernando, G. W.

    1998-03-01

    We present a method for the generation of interatomic potentials from first principles calculations using the marat>effective action formalism which leads to a systematic definition for effective two-body interatomic potentials. We do this by reducing the fully interacting system to an auxilliary system which interacts via a two-body interatomic potential. This definition can be trivially extended to higher order interatomic potentials. Unlike other approaches, our interatomic potentials are obtained from a sampling of configuration space pertaining to the thermodynamic environment of interest.

  16. Heavy metals in tributaries of Pampulha Reservoir, Minas Gerais

    Directory of Open Access Journals (Sweden)

    RIETZLER A. C.

    2001-01-01

    Full Text Available A great amount of heavy metals enter Pampulha Reservoir via it's main tributaries (Sarandi and Ressaca. Although no water quality classification has been carried out for these tributaries, the reservoir is expected to be in class 2 of the CONAMA-86 system. As part of a monitoring scheme of the Pampulha Watershed, heavy metals (Zn, Pb, Cd, Ni, Cu, Cr, Mn and Fe were investigated in the water at a control site (considered free from direct human influence and at potential sites of toxicity and contamination during August (dry season and November (wet season of 1998. The results for the first sampling period showed relatively high concentrations of zinc (0.22 mg.L-1 in the upper portion of the reservoir. The highest values of nickel and chromium (0.19 and 0.89 mg.L-1, respectively were found in the initial portion of the Sarandi Stream, while the highest concentrations of lead (0.05 mg.L-1, cadmium (0.014 mg.L-1, manganese (0.43 mg.L-1 and iron (15.25 mg.L-1 were detected in the Ressaca Stream by the landfill dump of Belo Horizonte. A relatively high concentration of cadmium was also detected at the confluence of the two streams. During the second sampling period, there was an increase in the concentrations of zinc at all sampling sites except the control, with values varying from 0.71 mg.L-1 (the Sarandi Stream to 2.50 mg.L-1 (the Ressaca Stream. Lead, cadmium, nickel and chromium concentrations were also higher in the Ressaca Stream, but not detected at the other sampling sites. Copper values were higher than in the first period: 0.10 mg.L-1 at the control up to 0.38 mg.L-1 at the confluence of the streams. Similar results were found for manganese and iron, with values reaching up to 19.30 and 125 mg.L-1, respectively. Moreover, all values recorded in the second sampling period were much higher than recommended for class 2 waters. These results emphasize the need for such monitoring in relation to better water quality management of this reservoir.

  17. Superfield tadpole method for SUSY effective potential

    International Nuclear Information System (INIS)

    Srivastava, P.P.

    1983-01-01

    Superfield formulation of Weinberg's tadpole method to compute the effective potential in supersymmetric theories is illustrated by considering the general renormalizable action involving only chiral scalar superfields. Unconstrained superfield potentials are introduced to simplify the ''effective'' superfield propagator which is derived in a compact form. (orig.)

  18. Ius Chasma Tributary Valleys and Adjacent Plains

    Science.gov (United States)

    2006-01-01

    This image covers valley tributaries of Ius Chasma, as well as the plains adjacent to the valleys. Ius Chasma is one of several canyons that make up the Valles Marineris canyon system. Valles Marineris likely formed by extension associated with the growth of the large volcanoes and topographic high of Tharsis to the northwest. As the ground was pulled apart, large and deep gaps resulted in the valleys seen in the top and bottom of this HiRISE image. Ice that was once in the ground could have also melted to create additional removal of material in the formation of the valleys. HiRISE is able to see the rocks along the walls of both these valleys and also impact craters in the image. Rock layers that appear lower down in elevation appear rougher and are shedding boulders. Near the top of the walls and also seen in patches along the smooth plains are brighter layers. These brighter layers are not shedding boulders so they must represent a different kind of rock formed in a different kind of environment than those further down the walls. Because they are highest in elevation, the bright layers are youngest in age. HiRISE is able to see dozens of the bright layers, which are perhaps only a meter in thickness. Darker sand dunes and ripples cover most of the plains and fill the floors of impact craters. Image PSP_001351_1715 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 9, 2006. The complete image is centered at -8.3 degrees latitude, 275.4 degrees East longitude. The range to the target site was 254.3 km (158.9 miles). At this distance the image scale ranges from 25.4 cm/pixel (with 1 x 1 binning) to 101.8 cm/pixel (with 4 x 4 binning). The image shown here has been map-projected to 25 cm/pixel and north is up. The image was taken at a local Mars time of 3:32 PM and the scene is illuminated from the west with a solar incidence angle of 59 degrees, thus the sun was about 31

  19. Experimental investigation on debris flow propagation and deposition in a downstream river by multiple tributaries

    Science.gov (United States)

    Stancanelli, L.; Lanzoni, S.; Foti, E.

    2012-12-01

    Debris flow risk assessment has been widely studied by many authors since it still represents one of the main cause of fatalities due to natural disasters. Thought in the last decades several improvements in the understanding of debris flow dynamics have been achieved, it must be said that the range of phenomena that can occur is so wide that a comprehensive vision is still missing. The present contribution aims at obtaining information regarding the interaction of multiple debris flows which propagate and deposit in the same river. Such a study has been inspired by a real case in which such an interaction enhanced the dramatic effects in terms of fatalities and damages. In particular, the aim of the research is to analyze experimentally the geometry of debris flow deposits conveyed in a main channel by two lateral tributaries, considering the influence of different parameters such as: slope, confluence angle and main channel discharge. The experimental set up includes a main channel (length 12 m, width 0,5m, height 0,70m) and two different lateral channels (length 3 m, width 0,3m, height 0,30m) located on the left side of the main channel, at an interaxis of about 1,2m. Six different acoustic level sensors and four pressure transducers have been installed along the experiment apparatus so that to monitor flow levels and pressures during both the propagation and deposition phases of the debris flow. At the end of each experiment a survey of the river bed has been carried out and the geometries of the observed deposition fans have been compared for the various experimental configurations investigated in the tests. A set of 20 experiments has been conducted by considering three different configurations of the confluence angle (90°-60°-45°), two different slopes of the tributary channels (15° e 17°), and three different trigger conditions (i.e., debris flows occurring simultaneously in the tributaries, or occurring first either in the upstream or in the

  20. Potential environmental effects of controlled thermonuclear reactors

    International Nuclear Information System (INIS)

    Young, J.R.; Gore, B.F.

    1976-01-01

    The following topics are discussed: (1) the fusion reaction, (2) approach to the environmental analysis, (3) the reference CTR, (4) CTR environmental effects, (5) CTR accident potential, and (6) the advanced CTR

  1. Potential Health Effects from Groundwater Pollution.

    Science.gov (United States)

    Goyer, Robert A.

    1985-01-01

    Discusses the growing awareness of potential toxicological effects of synthetic organic chemicals contaminating groundwater. Problems concerning pesticides, chlorination, epidemiologic studies, cancer, nephrotoxicity, and considerations of risk are addressed. Additional research in this area is advocated. (DH)

  2. Mercury Accumulation in Biota of Tributaries of the Finger Lakes, New York

    Science.gov (United States)

    Cleckner, L.; Razavi, R.; Cushman, S. F.; Massey, T.

    2016-12-01

    watersheds, but Blacknose Dace did reveal significant differences among the five lake watersheds investigated. This presentation will include results of a mixed effects general linear model to assess land use and DOC as predictors of Finger Lakes tributary biota Hg concentrations.

  3. The water quality of the river Svratka and its tributaries

    Directory of Open Access Journals (Sweden)

    Jan Grmela

    2013-01-01

    Full Text Available Water quality in river depends on water quality of its tributaries. During the year 2011 nine selected sites downstream under the Vír dam (from 108 to 79 river km were monitored. For observation were chosen tributaries Besének, Loučka, Nedvědička, Chlebský creek, Hodonínka, Vrtěžířský creek and Tresný creek. At the same time samples from the places above and under the whole monitored section of the river were taken. Basic physicochemical parameters were monitored monthly during the vegetation period. Flow velocity and discharge were assessed three times. Based on the water quality evaluation of, the river Svratka and its tributaries Hodonínka, Vrtěžířský creek and Tresný creek belong to the second quality class, tributaries Besének, Loučka, Nedvědička and Chlebský belong to the third quality class. In the monitored section the retention of phosphorus in annual amount about 2.2 tons were occurance. Annual volume of phosphorus at the end of observed section (upstream the Tišnov town was nearly 17.5 tons. Annual total balance of nitrogen at the end of monitored section was 700 tons per year and 6000 tons of carbon per year. The major source of these nutrients is the river Loučka.

  4. Simulation of hydrological processes in the Simiyu River, tributary of ...

    African Journals Online (AJOL)

    A spatially-distributed hydrologic model (WetSpa) is used to simulate hydrologic processes in the Simiyu River, a tributary of Lake Victoria, Tanzania. The model combines digital maps of topography, land-use and soil texture with observed daily meteorological time series to predict discharge hydrographs and spatial ...

  5. Assessment of the pollution in Aghien lagoon and its tributaries ...

    African Journals Online (AJOL)

    The influence of the pollutants in surface water quality when used for drinking water is of great concern in many developing countries. This study seeks to characterize the types of pollution in Aghien lagoon and its tributaries. For the sampling, water was taken at a depth of 50 cm from the earth surface. Samples were ...

  6. Spawning migration of Labeobarbus species to some tributary rivers ...

    African Journals Online (AJOL)

    Spawning migration of Labeobarbus species was studied from August to December 2013 in some tributary rivers (Qimon, Guanta, Shini, and Chibirna) of Lake Tana. Fish specimens and physico-chemical parameters were measured bimonthly in August and September but monthly from October to December. Adult fish ...

  7. Potential effects of gallium on cladding materials

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, D.F.; Beahm, E.C.; Besmann, T.M.; DeVan, J.H.; DiStefano, J.R.; Gat, U.; Greene, S.R.; Rittenhouse, P.L.; Worley, B.A.

    1997-10-01

    This paper identifies and examines issues concerning the incorporation of gallium in weapons derived plutonium in light water reactor (LWR) MOX fuels. Particular attention is given to the more likely effects of the gallium on the behavior of the cladding material. The chemistry of weapons grade (WG) MOX, including possible consequences of gallium within plutonium agglomerates, was assessed. Based on the calculated oxidation potentials of MOX fuel, the effect that gallium may have on reactions involving fission products and possible impact on cladding performance were postulated. Gallium transport mechanisms are discussed. With an understanding of oxidation potentials and assumptions of mechanisms for gallium transport, possible effects of gallium on corrosion of cladding were evaluated. Potential and unresolved issues and suggested research and development (R and D) required to provide missing information are presented.

  8. Potential effects of gallium on cladding materials

    International Nuclear Information System (INIS)

    Wilson, D.F.; Beahm, E.C.; Besmann, T.M.; DeVan, J.H.; DiStefano, J.R.; Gat, U.; Greene, S.R.; Rittenhouse, P.L.; Worley, B.A.

    1997-10-01

    This paper identifies and examines issues concerning the incorporation of gallium in weapons derived plutonium in light water reactor (LWR) MOX fuels. Particular attention is given to the more likely effects of the gallium on the behavior of the cladding material. The chemistry of weapons grade (WG) MOX, including possible consequences of gallium within plutonium agglomerates, was assessed. Based on the calculated oxidation potentials of MOX fuel, the effect that gallium may have on reactions involving fission products and possible impact on cladding performance were postulated. Gallium transport mechanisms are discussed. With an understanding of oxidation potentials and assumptions of mechanisms for gallium transport, possible effects of gallium on corrosion of cladding were evaluated. Potential and unresolved issues and suggested research and development (R and D) required to provide missing information are presented

  9. Occurrence of bacteria in Blue Marsh Lake and selected tributaries, Berks County, Pennsylvania; September-October 2001

    Science.gov (United States)

    Zimmerman, Michele L.

    2002-01-01

    The Commonwealth of Pennsylvania has water-quality standards that limit the number of specific bacteria in water that is considered safe for recreational use. Bacteria such as fecal streptococci, fecal coliforms, and Escherichia coli (E. coli) are used to assess recreational water quality because they usually live in the intestines of warm-blooded animals. Fecal indicator bacteria commonly are associated with waterborne disease-causing organisms (pathogens). These indicator bacteria are used routinely as a measure of the quality of water for recreational activities such as swimming, boating, and water skiing. If the indicator bacteria are present, effective measures could be taken to prevent the transmission or epidemic outbreak of waterborne diseases as a result of contamination of these waters from human or animal waste.Blue Marsh Lake is on Tulpehocken Creek in Berks County, Pa., and drains a largely agricultural basin. Land use in the basin is approximately 60 percent cropland, and 85 percent of the farms are livestock and poultry farms.The potential sources of fecal bacteria are:geese that inhabit the recreational areas of the lake,humans that visit the Dry Brooks Day Use Area (swimming area), andfarm animals, wastewater facilities, and household septic systems in the basin (bacteria from these sources could enter the lake through tributaries).To meet the recreational water-quality standard, lake water may not have more than 200 colony-forming units (CFU) of fecal coliforms per 100 milliliters (mL). During the week of July 23, 2001, data collected by the U.S. Army Corps of Engineers (USACE) at the swimming area at Blue Marsh Lake showed concentrations of fecal coliforms in the water exceeding the standard. To determine the extent of elevated concentrations of fecal indicator bacteria, further study of the lake and selected tributaries was needed.

  10. A Synthesis of Sierran Forest Biomass Management Studies and Potential Effects on Water Quality

    Directory of Open Access Journals (Sweden)

    Peter J. Weisberg

    2010-09-01

    Full Text Available The Lake Tahoe basin, located along the California and Nevada border between the Carson and Sierra Nevada mountain ranges, represents a complex forested ecosystem consisting of numerous sub-watersheds and tributaries that discharge directly to Lake Tahoe. This synthesis focuses on historical and current nutrient pools and the effects of biomass management in watersheds of the basin relative to their potential impacts on nutrient (N, P related discharge water quality. An accumulating forest floor as a result of fire suppression has resulted in the build-up of large nutrient pools that now provide a “natural” source of long term nutrient availability to surface waters. As a consequence, stand and forest floor replacing wildfire may cause a large magnitude nutrient mobilization impact on runoff water quality. Hence, mechanical harvest and controlled burning have become popular management strategies. The most ecologically significant long-term effects of controlled fire appear to be the loss of C and N from the forest floor. Although the application of controlled fire may have some initial impact on overland/litter interflow nutrient loading, controlled burning in conjunction with mechanical harvest has the potential to improve runoff water quality by reducing N and P discharge and improving the overall health of forest ecosystems without the danger of a high intensity wildfire.

  11. 33 CFR 207.160 - All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary...

    Science.gov (United States)

    2010-07-01

    ... management of the lock, and of the area set aside as the lock area, including the lock approach channels. He... canals and channels of all types, which are tributary to or connected by other waterways with the... other floating thing in the lock or approaches except by or under the direction of the lockmaster or his...

  12. Assessing dam development, land use conversion, and climate change pressures on tributary river flows and water quality of the Mekong's Tonle Sap basin.

    Science.gov (United States)

    Cochrane, T. A.; Arias, M. E.; Oeurng, C.; Arnaiz, M.; Piman, T.

    2016-12-01

    The Tonle Sap Lake is Southeast Asia's most productive freshwater fishery, but the productivity of this valuable ecosystem is under threat from extensive development in the lower Mekong. With dams potentially blocking all major tributaries along the lower Mekong River, the role of local Tonle Sap basin tributaries for maintaining environmental flows, sediment loads, and fish recruitment is becoming increasingly critical. Development within the Tonle Sap basin, however, is not stagnant. Developers are proposing extensive dam development in key Tonle Sap tributaries (see Figure). Some dams will provide hydroelectricity and others will provide opportunities for large-scale irrigation resulting in agro-industrial expansion. There is thus an immediate need to assess the current situation and understand future effects of dam development and land use conversion under climate change on local riverine ecosystems. A combination of remote sensing, field visits, and hydro-meteorological data analyses enabled an assessment of water infrastructure and agricultural development in the basin. The application of SWAT for modelling flows and water quality combined with HEC-RESSIM for reservoir operations enabled for a holistic modelling approach. Initial results show that dams and land use change dominate flow and water quality responses, when compared to climate change. Large ongoing dam and irrigation development in the Pursat and Battambang subbasins will critically alter the natural river flows to the Tonle Sap Lake. Some of the observed dams did not have provisions for sediment flushing, clearing of flooded areas, fish passages, or other environmental protection measures. Poor planning and operation of this infrastructure could have dire consequences on the fragile riverine ecosystem of Tonle Sap tributaries, resulting in fish migration barriers, losses in aquatic habitats, and ecological degradation. The seemingly chaotic development in the Tonle Sap basin induces a great level

  13. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Science.gov (United States)

    2010-07-01

    ..., English Kills and their tributaries. 117.801 Section 117.801 Navigation and Navigable Waters COAST GUARD....801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a) The following requirements apply to all bridges across Newtown Creek, Dutch Kills, English Kills, and their tributaries: (1) The...

  14. A Tributary of Benin River, Sou

    African Journals Online (AJOL)

    PROF HORSFALL

    water by the presence and levels of concentration of sodium and magnesium ions and to some extent calcium ions. These ions help buffer the effect of bicarbonate and carbonate ions, thus maintaining the. pH (Raymont, 1983). Values of conductivity recorded are an indication of negligible impact of human activities in the ...

  15. Potential effects of coalbed natural gas development on fish and aquatic resources

    Science.gov (United States)

    Farag, Aïda M.; Harper, David D.; Senecal, Anna C.; Hubert, Arthur E.; Reddy, K.J.

    2010-01-01

    The purpose of this chapter is to provide a summary of issues and findings related to the potential effects of coalbed natural gas (CBNG) development on fish and other aquatic resources. We reviewed CBNG issues from across the United States and used the Powder River Basin of Wyoming as a case study to exemplify some pertinent issues. The quality of water produced during CBNG extraction is quite variable. High total dissolved solids in many CBNG produced waters are of concern relative to fish and other aquatic organisms. Untreated CBNG produced water has the potential to be toxic to fish and aquatic organisms. Of particular concern at some locations in the Powder River basin are elevated concentrations of sodium bicarbonate which have been shown to be toxic to some species of larval fish and aquatic invertebrates. The areas affected by direct toxicity were limited to headwaters and small tributaries studied in the basin. The potential effects of organic compounds used during well drilling and CBNG production on water quality, fish, and aquatic organisms are not well defined. Water produced from CBNG wells that is low in salts or has been treated to remove salts may be discharged into ephemeral or perennially-flowing streams. Higher flows in small streams can enhance erosion and affect habitat for fish and aquatic organisms. In Great Plains rivers, such as the Powder River, fish and aquatic invertebrate communities are structured by extreme environmental conditions. Direct discharge of CBNG produced water during periods of very low or no surface flow may cause shifts in the aquatic community structure. Additional effects of CBNG development on fish and aquatic organisms may stem from road building and pipeline construction, roads crossing streams and ephemeral water courses, the possible spread of invasive organisms, potential spills of toxic substances, and increased harvest of sport fish. 

  16. On Effective Potential in Tortoise Coordinate

    Science.gov (United States)

    Ganjali, M. A.

    2012-08-01

    In this paper, we study the field dynamics in Tortoise coordinate where the equation of motion of a scalar can be written as Schrodinger-like form. We obtain a general form for effective potential by finding the Schrodinger equation for scalar and spinor fields and study its global behavior in some black hole backgrounds in three dimension such as BTZ black holes, new type black holes and black holes with no horizon. Especially, we study the asymptotic behavior of potential at infinity, horizons and origin and find that its asymptotic in BTZ and new type solution is completely different from that of vanishing horizon solution. In fact, potential for vanishing horizon goes to a fixed quantity at infinity, while in BTZ and new type black hole we have an infinite barrier.

  17. Interpolation effects in tabulated interatomic potentials

    Science.gov (United States)

    Wen, M.; Whalen, S. M.; Elliott, R. S.; Tadmor, E. B.

    2015-10-01

    Empirical interatomic potentials are widely used in atomistic simulations due to their ability to compute the total energy and interatomic forces quickly relative to more accurate quantum calculations. The functional forms in these potentials are sometimes stored in a tabulated format, as a collection of data points (argument-value pairs), and a suitable interpolation (often spline-based) is used to obtain the function value at an arbitrary point. We explore the effect of these interpolations on the potential predictions by calculating the quasi-harmonic thermal expansion and finite-temperature elastic constant of a one-dimensional chain compared with molecular dynamics simulations. Our results show that some predictions are affected by the choice of interpolation regardless of the number of tabulated data points. Our results clearly indicate that the interpolation must be considered part of the potential definition, especially for lattice dynamics properties that depend on higher-order derivatives of the potential. This is facilitated by the Knowledgebase of Interatomic Models (KIM) project, in which both the tabulated data (‘parameterized model’) and the code that interpolates them to compute energy and forces (‘model driver’) are stored and given unique citeable identifiers. We have developed cubic and quintic spline model drivers for pair functional type models (EAM, FS, EMT) and uploaded them to the OpenKIM repository (https://openkim.org).

  18. [The effect of cigarettes on somatosensory potentials].

    Science.gov (United States)

    León, F E; Suwazono, S; Arimura, K; Osame, M

    1998-01-01

    The physiological and pathological effects of cigarettes on the nervous system have been widely studied, but none of the investigations carried out has enabled us to determine the degree to which nicotine may affect the central pathways of somatosensorial evoked potentials in humans. Following parameters established internationally for investigation of the effects of nicotine on the nervous system, we find that the N18 wave obtained by stimulation of the median nerve before smoking completely disappears after smoking for 3 minutes and reappears 10 minutes after smoking has stopped. Therefore, we conclude that the action of nicotine on these evoked potentials is mainly subcortical, and for this reason it is essential to investigate the toxicological history before carrying out any clinical or neurophysiological study, since this might affect the results obtained.

  19. Taming infrared divergences in the effective potential

    International Nuclear Information System (INIS)

    Elias-Miro, J.; Konstandin, T.

    2014-06-01

    The Higgs effective potential in the Standard Model (SM), calculated perturbatively, generically suffers from infrared (IR) divergences when the (field-dependent) tree-level mass of the Goldstone bosons goes to zero. Such divergences can affect both the potential and its first derivative and become worse with increasing loop order. In this paper we show that these IR divergences are spurious, we perform a simple resummation of all IR-problematic terms known (up to three loops) and explain how to extend the resummation to cure all such divergences to any order. The method is of general applicability and would work in scenarios other than the SM. Our discussion has some bearing on a scenario recently proposed as a mechanism for gauge mediation of scale breaking in the ultraviolet, in which it is claimed that the low-energy Higgs potential is non-standard. We argue that all non-decoupling effects from the heavy sector can be absorbed in the renormalization of low-energy parameters leading to a SM-like effective theory.

  20. Garlic: a review of potential therapeutic effects

    Science.gov (United States)

    Bayan, Leyla; Koulivand, Peir Hossain; Gorji, Ali

    2014-01-01

    Throughout history, many different cultures have recognized the potential use of garlic for prevention and treatment of different diseases. Recent studies support the effects of garlic and its extracts in a wide range of applications. These studies raised the possibility of revival of garlic therapeutic values in different diseases. Different compounds in garlic are thought to reduce the risk for cardiovascular diseases, have anti-tumor and anti-microbial effects, and show benefit on high blood glucose concentration. However, the exact mechanism of all ingredients and their long-term effects are not fully understood. Further studies are needed to elucidate the pathophysiological mechanisms of action of garlic as well as its efficacy and safety in treatment of various diseases. PMID:25050296

  1. Could piracetam potentiate behavioural effects of psychostimulants?

    Science.gov (United States)

    Slais, Karel; Machalova, Alena; Landa, Leos; Vrskova, Dagmar; Sulcova, Alexandra

    2012-08-01

    Press and internet reports mention abuse of nootropic drug piracetam (PIR) in combination with psychostimulants methamphetamine (MET) or 4-methylenedioxymethamphetamine (MDMA). These combinations are believed to produce more profound desirable effects, while decreasing hangover. However, there is a lack of valid experimental studies on such drug-drug interactions in the scientific literature available. Our hypothesis proposes that a functional interaction exists between PIR and amphetamine psychostimulants (MET and MDMA) which can potentiate psychostimulant behavioural effects. Our hypothesis is supported by the results of our pilot experiment testing acute effects of drugs given to mice intraperitoneally (Vehicle, n=12; MET 2.5mg/kg, n=10; MDMA 2.5mg/kg, n=11; PIR 300 mg/kg, n=12; PIR+MET, n=12; PIR+MDMA, n=11) in the Open Field Test (Actitrack, Panlab, Spain). PIR given alone caused no significant changes in mouse locomotor/exploratory behaviour, whereas the same dose combined with either MET or MDMA significantly enhanced their stimulatory effects. Different possible neurobiological mechanism underlying drug-drug interaction of PIR with MET or MDMA are discussed, as modulation of dopaminergic, glutamatergic or cholinergic brain systems. However, the interaction with membrane phospholipids seems as the most plausible mechanism explaining PIR action on activities of neurotransmitter systems. Despite that our behavioural experiment cannot serve for explanation of the pharmacological mechanisms of these functional interactions, it shows that PIR effects can increase behavioural stimulation of amphetamine drugs. Thus, the reported combining of PIR with MET or MDMA by human abusers is not perhaps a coincidental phenomenon and may be based on existing PIR potential to intensify acute psychostimulant effects of these drugs of abuse. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Potential effects of organizational uncertainty on safety

    International Nuclear Information System (INIS)

    Durbin, N.E.; Lekberg, A.; Melber, B.D.

    2001-12-01

    When organizations face significant change - reorganization, mergers, acquisitions, down sizing, plant closures or decommissioning - both the organizations and the workers in those organizations experience significant uncertainty about the future. This uncertainty affects the organization and the people working in the organization - adversely affecting morale, reducing concentration on safe operations, and resulting in the loss of key staff. Hence, organizations, particularly those using high risk technologies, which are facing significant change need to consider and plan for the effects of organizational uncertainty on safety - as well as planning for other consequences of change - technical, economic, emotional, and productivity related. This paper reviews some of what is known about the effects of uncertainty on organizations and individuals, discusses the potential consequences of uncertainty on organizational and individual behavior, and presents some of the implications for safety professionals

  3. Effect of relative humidity on solar potential

    International Nuclear Information System (INIS)

    Soezen, Adnan; Arcaklioglu, Erol

    2005-01-01

    In this study, the effect of relative humidity on solar potential is investigated using artificial neural-networks. Two different models are used to train the neural networks. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine-duration, and mean temperature) are used in the input layer of the network (Model 1). But, relative humidity values are added to one network in model (Model 2). In other words, the only difference between the models is relative humidity. New formulae based on meteorological and geographical data, have been developed to determine the solar energy potential in Turkey using the networks' weights for both models. Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) learning algorithms and a logistic sigmoid transfer-function were used in the network. The best approach was obtained by the SCG algorithm with nine neurons for both models. Meteorological data for the four years, 2000-2003, for 18 cities (Artvin, Cesme, Bozkurt, Malkara, Florya, Tosya, Kizilcahamam, Yenisehir, Edremit, Gediz, Kangal, Solhan, Ergani, Selcuk, Milas, Seydisehir, Siverek and Kilis) spread over Turkey have been used as data in order to train the neural network. Solar radiation is in output layer. One month for each city was used as test data, and these months have not been used for training. The maximum mean absolute percentage errors (MAPEs) for Tosya are 2.770394% and 2.8597% for Models 1 and 2, respectively. The minimum MAPEs for Seydisehir are 1.055205% and 1.041% with R 2 (99.9862%, 99.9842%) for Models 1 and 2, respectively, in the SCG algorithm with nine neurons. The best value of R 2 for Models 1 and 2 are for Seydisehir. The minimum value of R 2 for Model 1 is 99.8855% for Tosya, and the value for Model 2 is 99.9001% for Yenisehir. Results show that the humidity has only a negligible effect upon the prediction of solar potential using artificial neural-networks

  4. The influence of tributary flow density differences on the hydrodynamic behavior of a confluent meander bend and implications for flow mixing

    Science.gov (United States)

    Herrero, Horacio S.; Díaz Lozada, José M.; García, Carlos M.; Szupiany, Ricardo N.; Best, Jim; Pagot, Mariana

    2018-03-01

    The goal of this study is to evaluate the influence of tributary flow density differences on hydrodynamics and mixing at a confluent meander bend. A detailed field characterization is performed using an Acoustic Doppler Current Profiler (ADCP) for quantification of the 3D flow field, flow discharge and bathymetry, as well as CTD measurements (conductivity, temperature, depth) to characterize the patterns of mixing. Satellite images of the confluence taken at complementary times to the field surveys were analyzed to evaluate the confluence hydrodynamics at different flow conditions. The results illustrate the differences in hydrodynamics and mixing length in relation to confluences with equal density tributaries. At low-density differences, and higher discharge ratio (Qr) between the two rivers, the flow is similar to equi-density confluent meander bends. In contrast, at high-density differences (low Qr), the tributary flow is confined to near the confluence but the density difference causes the flow to move across channel. In this case, the density difference causes the lateral spread of the tributary flow to be greater than at a greater Qr when the density difference is less. These results illustrate the potential importance of density differences between tributaries in determining the rate and spatial extent of mixing and sediment dispersal at confluent meander bends.

  5. Nanomaterials potentiating standard chemotherapy drugs' effect

    Science.gov (United States)

    Kazantsev, S. O.; Korovin, M. S.

    2017-09-01

    Application of antitumor chemotherapeutic drugs is hindered by a number of barriers, multidrug resistance that makes effective drug deposition inside cancer cells difficult is among them. Recent research shows that potential efficiency of anticancer drugs can be increased with nanoparticles. This review is devoted to the application of nanoparticles for cancer treatment. Various types of nanoparticles currently used in medicine are reviewed. The nanoparticles that have been used for cancer therapy and targeted drug delivery to damaged sites of organism are described. Also, the possibility of nanoparticles application for cancer diagnosis that could help early detection of tumors is discussed. Our investigations of antitumor activity of low-dimensional nanostructures based on aluminum oxides and hydroxides are briefly reviewed.

  6. Finding quantum effects in strong classical potentials

    Science.gov (United States)

    Hegelich, B. Manuel; Labun, Lance; Labun, Ou Z.

    2017-06-01

    The long-standing challenge to describing charged particle dynamics in strong classical electromagnetic fields is how to incorporate classical radiation, classical radiation reaction and quantized photon emission into a consistent unified framework. The current, semiclassical methods to describe the dynamics of quantum particles in strong classical fields also provide the theoretical framework for fundamental questions in gravity and hadron-hadron collisions, including Hawking radiation, cosmological particle production and thermalization of particles created in heavy-ion collisions. However, as we show, these methods break down for highly relativistic particles propagating in strong fields. They must therefore be improved and adapted for the description of laser-plasma experiments that typically involve the acceleration of electrons. Theory developed from quantum electrodynamics, together with dedicated experimental efforts, offer the best controllable context to establish a robust, experimentally validated foundation for the fundamental theory of quantum effects in strong classical potentials.

  7. Effects of aging on laser evoked potentials.

    Science.gov (United States)

    Creac'H, Christelle; Bertholon, Alexandre; Convers, Philippe; Garcia-Larrea, Luis; Peyron, Roland

    2015-05-01

    Aging has been reported to reduce the amplitude of laser evoked potentials. However, it is unknown whether this effect depends on the length of the sensory fibers. This is an important issue, because most painful neuropathies are length-dependent. We conducted a study of 40 healthy subjects, half of whom were older than age 50 years. Nociceptive stimuli were delivered to the feet and thighs using a CO2 laser stimulator. Detection and pain perception thresholds did not correlate with age. Latencies of N1, N2, and P2 correlated positively with age on the feet but not on the thighs, whereas the amplitude of N2-P2 decreased with age for both areas. The effects of aging on latencies may reflect a distal loss of peripheral inputs and a length-dependent de-synchronization of the ascending nociceptive volley. Additional changes in peripheral and central processes may explain the diffuse decrease of N2-P2 amplitudes observed with aging. © 2014 Wiley Periodicals, Inc.

  8. Electron Correlations in Local Effective Potential Theory

    Directory of Open Access Journals (Sweden)

    Viraht Sahni

    2016-08-01

    Full Text Available Local effective potential theory, both stationary-state and time-dependent, constitutes the mapping from a system of electrons in an external field to one of the noninteracting fermions possessing the same basic variable such as the density, thereby enabling the determination of the energy and other properties of the electronic system. This paper is a description via Quantal Density Functional Theory (QDFT of the electron correlations that must be accounted for in such a mapping. It is proved through QDFT that independent of the form of external field, (a it is possible to map to a model system possessing all the basic variables; and that (b with the requirement that the model fermions are subject to the same external fields, the only correlations that must be considered are those due to the Pauli exclusion principle, Coulomb repulsion, and Correlation–Kinetic effects. The cases of both a static and time-dependent electromagnetic field, for which the basic variables are the density and physical current density, are considered. The examples of solely an external electrostatic or time-dependent electric field constitute special cases. An efficacious unification in terms of electron correlations, independent of the type of external field, is thereby achieved. The mapping is explicated for the example of a quantum dot in a magnetostatic field, and for a quantum dot in a magnetostatic and time-dependent electric field.

  9. Concentration, flux, and trend estimates with uncertainty for nutrients, chloride, and total suspended solids in tributaries of Lake Champlain, 1990–2014

    Science.gov (United States)

    Medalie, Laura

    2016-12-20

    increased in 10 tributaries; and fluxes of dissolved phosphorus decreased in 4 and increased in 10 tributaries (where the number of increasing and decreasing trends does not add up to 18, the remainder of tributaries had no trends). Concentrations and fluxes of nitrogen decreased in 10 and increased in 4 tributaries and of chloride decreased in 2 and increased in 15 tributaries. Concentrations of total suspended solids decreased in 4 and increased in 8 tributaries, and fluxes of total suspended solids decreased in 3 and increased in 11 tributaries. Although time intervals for the percent changes from this report are not completely synchronous with those from previous studies, the numbers of and specific tributaries with overall negative percent changes in concentration and flux are similar. Concentration estimates of total phosphorus in the Winooski River were used to trace whether changes in trends between a previous study and the current study were due generally to differences in model specifications or differences from 4 years of additional data. The Winooski River analysis illustrates several things: that keeping all model specifications equal, concentration estimates increased from 2010 to 2014; the effects of a smoothing algorithm used in the current study that was not available previously; that narrowing model half-window widths increased year-to-year variations; and that the change from an annual to a 9-month basis by omitting winter estimates changed a few individual points but not the overall shape of the flow-normalized curve. Similar tests for other tributaries showed that the primary effect of differences in model specifications between the previous and current studies was perhaps to increase scatter over time but that changes in trends generally were the result of 4 years of additional data rather than artifacts of model differences.

  10. Effective field theory approaches for tensor potentials

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, Maximilian

    2016-11-14

    Effective field theories are a widely used tool to study physical systems at low energies. We apply them to systematically analyze two and three particles interacting via tensor potentials. Two examples are addressed: pion interactions for anti D{sup 0}D{sup *0} scattering to dynamically generate the X(3872) and dipole interactions for two and three bosons at low energies. For the former, the one-pion exchange and for the latter, the long-range dipole force induce a tensor-like structure of the potential. We apply perturbative as well as non-perturbative methods to determine low-energy observables. The X(3872) is of major interest in modern high-energy physics. Its exotic characteristics require approaches outside the range of the quark model for baryons and mesons. Effective field theories represent such methods and provide access to its peculiar nature. We interpret the X(3872) as a hadronic molecule consisting of neutral D and D{sup *} mesons. It is possible to apply an effective field theory with perturbative pions. Within this framework, we address chiral as well as finite volume extrapolations for low-energy observables, such as the binding energy and the scattering length. We show that the two-point correlation function for the D{sup *0} meson has to be resummed to cure infrared divergences. Moreover, next-to-leading order coupling constants, which were introduced by power counting arguments, appear to be essential to renormalize the scattering amplitude. The binding energy as well as the scattering length display a moderate dependence on the light quark masses. The X(3872) is most likely deeper bound for large light quark masses. In a finite volume on the other hand, the binding energy significantly increases. The dependence on the light quark masses and the volume size can be simultaneously obtained. For bosonic dipoles we apply a non-perturbative, numerical approach. We solve the Lippmann-Schwinger equation for the two-dipole system and the Faddeev

  11. Linking Benthic Macroinvertebrates and Physicochemical Variables for Water Quality Assessment in Saigon River and Its Tributaries, Vietnam

    Science.gov (United States)

    Pham, A. D.

    2017-10-01

    The benthic macroinvertebrates living on the bottom channels are one of the most promising of the potential indicators of river health for the Saigon River and its tributaries with hydrochemistry playing a supporting role. An evaluation of the interrelationships within this approach deems necessary. This work identified and tested these relationships to improve the method for water quality assessment. Data from over 4,500 km2 watershed were used as a representative example for the Saigon River and its tributaries. The data covered the period March and September, 2007, 2008, 2009, 2010 and 2015. To implement this evaluation, the analyses were based on accepted the methodology of Mekong River Commission and the studies of scientific group for the biological status assessment. For correlation analyses, the selected environmental variables were compared with the ecological indices, based on benthic macroinvertebrates. The results showed that the metrics of Species Richness, H’, and 1-DS had significant and strong relationships with the water quality variables of DO, BOD5, T_N, and TP (R2 = 0.3751 – 0.8866; P macroinvertebrates did not have a statistically significant relationship with any water quality variables (R2 = 0.0000 – 0.0744; P > 0.05). Additionally, the metrics of Species Richness, H’, and 1-DS had negatively correlated with the pH and TSS. Both univariate and multivariate analyses were used to examine the ecological quality of the Saigon River and its tributaries using benthic macroinvertebrates seems to be the most sensitive indicator to correlate with physicochemical variables. This demonstrated that it could be applied to describe the water quality in the Saigon River and its tributaries.

  12. Physico-chemical assessment of sediments of Tamarindo estuary and its tributaries, Guanacaste, Costa Rica

    Directory of Open Access Journals (Sweden)

    Francela María Bravo Chaves

    2016-03-01

    Full Text Available Sediments of Tamarindo estuary and its tributaries were evaluated in order to determine the effect of anthropogenic activities of the surrounding communities. The evaluation relied on texture, total phosphorus, organic matter, and heavy metal (Pb, Cu, Ni and Cr analyses. The study spanned four sampling campaigns between October 2007 and April 2008, including four climatic seasons: rainy season, rainy-dry transition, dry season and dryrainy transition. Five sampling points were selected at Tamarindo estuary and three additional sites were set at Matapalo, Lomas and Lajas rivers. Ontario Ministry of the Environment regulation was used to evaluate sediment quality. It was determined that theanthropogenic activities of the surrounding communities exert a negative impact over the sediment quality; the pollution effect caused by such activities was rated as lower effect.

  13. New Techniques for Real-Time Stage Forecasting for Tributaries in the Nashville Area

    Science.gov (United States)

    Charley, W.; Moran, B.; LaRosa, J.

    2011-12-01

    has been derived from the Corps Water Management System (CWMS). The modeling component takes observed and forecasted rainfall to compute river flow with the program HEC-HMS. The river hydraulics program, HEC-RAS, computes river stages and water surface profiles. An inundation boundary and depth map of water in the flood plain is computed from HEC-RAS Mapper. The user-configurable sequence of modeling software allows engineers to evaluate and compare hydraulic impacts for various "what if?" scenarios. The implementation of these techniques and HEC-RTS is examined for the Mill Creek basin, the 108 square mile tributary basin south east of Nashville. Mill Creek has an average annual flow of 150 CFS and a short response time. It has suffered major damage from the 2010 and other events. The accuracy and effectiveness of the techniques in the integrated tool HEC-RTS is evaluated.

  14. The fishermen were right: experimental evidence for tributary refuge hypothesis during floods.

    Science.gov (United States)

    Koizumi, Itsuro; Kanazawa, Yukiyo; Tanaka, Yuuki

    2013-05-01

    Fishermen often anecdotally report an unexpected increase of fish caught in small tributary streams during floods, presumably due to refuge-seeking behavior from the main stem. From a population perspective, this implies the significance of refuge habitats and connectivity for population viability against natural disturbances. Despite the plausibility, however, surprisingly few studies have examined the tributary refuge hypothesis, mainly due to the difficulty in field survey during floods. Here, we made use of a large-scale controlled flood to assess whether fishes move into tributaries during flooding in the main stem. A planned water release from the Satsunai River Dam located on Hokkaido Island in Japan rapidly increased the main stem discharge by more than 20-fold. Before, during, and after flooding censuses in four tributaries provided evidence of the refuge-seeking behavior of fishes from the main stem. For example, more than 10 Dolly Varden char, a salmonid fish, were caught in a tributary during the flood, even though almost no individuals were captured before or after the flood. The fish responded immediately to the flooding, suggesting the need for studies during disturbances. In addition, the likelihood of refuge movements varied among tributaries, suggesting the importance of local environmental differences between tributary and the main stem habitats. This is the first study to experimentally confirm the tributary refuge hypothesis, and underscores the roles of habitat diversity and connectivity during disturbances, even though some habitats are not used during normal conditions.

  15. Influence of Methylmercury from Tributary Streams on Mercury Levels in Savannah River Asiatic Clams

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.H.

    2004-03-01

    Average methylmercury levels in five Savannah River tributary streams sampled 11 times over two years were nearly twice as high as in the Savannah River. Total mercury levels in the tributaries did not differ significantly from the river. All of the tributaries drained extensive wetlands that would be expected to support comparatively high rates of methylation. Mercury concentrations in Asiatic clams (Corbicula fluminea) collected from the discharge plumes of Savannah River tributaries were significantly higher than in Asiatic clams collected from the Savannah River upstream from the tributary mouths . These results indicate that streams draining wetlands into coastal plain rivers can create localized areas of elevated methylmercury with resulting increases in the mercury levels of river biota.

  16. Geomorphic Response of Trinity River Tributary Deltas under High Flow Restoration Hydrology

    Science.gov (United States)

    Stewart, R. L.; Gaeuman, D.

    2016-12-01

    Sediments supplied to regulated rivers from unregulated tributaries accelerate sediment transport processes near the tributary confluences. Repeat topographic surveys completed between tributary events and mainstem flows are differenced to investigate sediment transport processes and tributary delta dynamics on the Trinity River in Northern California. The Trinity River was dammed in the 1960's when most of its water was diverted to California's Central Valley, greatly reducing the frequency of flows competent to mobilize course sediments. During the first 20 years after dam completion about 20% of basin inflow was released to the river, and geomorphic flows occurred only during rare safety-of-dams releases. After dam completion, tributaries to the Trinity continued to flow without regulation and many of them delivered increased sediment loads as a result of land use practices in the uplands. Increased sediment supply from tributaries and the reduction in mainstem transport capacity caused by flow regulation led to the formation of large deltas at the major tributary confluences. Recent restoration efforts include geomorphic flows designed to mobilize sediments delivered by the tributaries and restore the river reach to an equilibrium state. Prior to restoration, peak flows at the dam site once exceeded 2,000 cms and had 2-year return interval flow of 400 cms. The partially restored geomorphic flows have maximum release capacity of 350 cms and 2-year return interval of 170 cms. This study compares repeat surveys of two tributary confluences, Rush Creek which enters the mainstem opposite of an alluvial valley bottom and Indian Creek which enters opposite of a non-erodible valley wall. Results indicate lateral channel migration and floodplain building processes occurring during lower magnitude tributary events. Higher magnitude mainstem flow events redistribute sediments to downstream reaches. Both confluences continue to adjust toward a state of equilibrium through

  17. An effective pair potential for liquid semiconductor, Se: Structure and ...

    Indian Academy of Sciences (India)

    The effective pair potential of liquid semiconductor Se is extracted from its experimental structure factor data using an accurate liquid state theory and this shows important basic features. A model potential incorporating the basic features of the structure factor extracted potential is suggested. This model potential is then used ...

  18. Potential climatic effects of anthropogenic aerosols

    International Nuclear Information System (INIS)

    Pueschel, R.F.

    1993-01-01

    Aerosols act as part of the climate system through their influence on solar and terrestrial radiation. The effect of anthropogenic aerosols on the reduction of visibility is explored in this chapter. Elemental carbon has been identified as the most effective visibility-reducing species. Most of the visibility reduction is due to particles with diameter smaller than 2.5 μm. Studies indicate that sulfate is also a very important aerosol species that results in low visibility and high turbidity. Radiative properties such as aerosol single-scattering albedo values and absorption-to-backscatter ratios purported to produce warming or cooling effects of aerosols are discussed. It is concluded that aerosol clouds have a tendency to cool when they are over a low-albedo surface and have a tendency to warm when they are over high-albedo surfaces such as snow. Anthropogenic aerosols have a tendency to warm the earth's atmospheric system, based on calculations and assumed aerosol optical properties. However, this effect is somewhat offset by the absorption and re-emission into space of infrared terrestrial radiation. The net effect depends on the ratio of the absorption coefficients in the visible and infrared and also on the surface albedo. The effects on infrared radiation are documented for two anthropogenic aerosol sources in the United States, the Denver metropolitan area and power plant plumes in New Mexico, through calculations and measurements. Measured cooling rates within an aerosol plume are not sufficient to offset the warming rate due to absorption of short-wave radiation. Research indicates that anthropogenic aerosols can possibly cause local-scale warming of the atmosphere, but global-scale climatic effects remain an open question

  19. Temperature corrections, supersymmetric effective potentials and inflation

    International Nuclear Information System (INIS)

    Binetruy, P.; Gaillard, M.K.; California Univ., Berkeley

    1985-01-01

    We calculate the one-loop temperature corrections to general potentials in N=1 supergravity, and study the conditions under which a new inflationary scenario is possible. The results are sensitive to the total number N of chiral superfields. For large N, we find that in 'hidden sector' models supersymmetry must be broken at a scale governed by the energy density of the false vacuum: msub(3/2) > or approx. 2√8π μ 2 /Msub(p), where μ approx.= (10 -3 -10 -4 )Msub(p) in typical inflationary scenarios. We also discuss an alternative picture where inflation occurs at the preonic level, before the preon-confining phase transition. (orig.)

  20. Inter-Tributary Movements by Resident Salmonids across a Boreal Riverscape.

    Directory of Open Access Journals (Sweden)

    Kale T Bentley

    Full Text Available Stream-dwelling fishes inhabit river networks where resources are distributed heterogeneously across space and time. Current theory emphasizes that fishes often perform large-scale movements among habitat patches for reproduction and seeking refugia, but assumes that fish are relatively sedentary during growth phases of their life cycle. Using stationary passive integrated transponder (PIT-tag antennas and snorkel surveys, we assessed the individual and population level movement patterns of two species of fish across a network of tributaries within the Wood River basin in southwestern Alaska where summer foraging opportunities vary substantially among streams, seasons, and years. Across two years, Arctic grayling (Thymallus arcticus and rainbow trout (Oncorhynchus mykiss exhibited kilometer-scale movements among streams during the summer growing season. Although we monitored movements at a small fraction of all tributaries used by grayling and rainbow trout, approximately 50% of individuals moved among two or more streams separated by at least 7 km within a single summer. Movements were concentrated in June and July, and subsided by early August. The decline in movements coincided with spawning by anadromous sockeye salmon, which offer a high-quality resource pulse of food to resident species. Inter-stream movements may represent prospecting behavior as individuals seek out the most profitable foraging opportunities that are patchily distributed across space and time. Our results highlight that large-scale movements may not only be necessary for individuals to fulfill their life-cycle, but also to exploit heterogeneously spaced trophic resources. Therefore, habitat fragmentation and homogenization may have strong, but currently undescribed, ecological effects on the access to critical food resources in stream-dwelling fish populations.

  1. Inter-Tributary Movements by Resident Salmonids across a Boreal Riverscape

    Science.gov (United States)

    Bentley, Kale T.; Schindler, Daniel E.; Armstrong, Jonathan B.; Cline, Timothy J.; Brooks, Gabriel T.

    2015-01-01

    Stream-dwelling fishes inhabit river networks where resources are distributed heterogeneously across space and time. Current theory emphasizes that fishes often perform large-scale movements among habitat patches for reproduction and seeking refugia, but assumes that fish are relatively sedentary during growth phases of their life cycle. Using stationary passive integrated transponder (PIT)-tag antennas and snorkel surveys, we assessed the individual and population level movement patterns of two species of fish across a network of tributaries within the Wood River basin in southwestern Alaska where summer foraging opportunities vary substantially among streams, seasons, and years. Across two years, Arctic grayling (Thymallus arcticus) and rainbow trout (Oncorhynchus mykiss) exhibited kilometer-scale movements among streams during the summer growing season. Although we monitored movements at a small fraction of all tributaries used by grayling and rainbow trout, approximately 50% of individuals moved among two or more streams separated by at least 7 km within a single summer. Movements were concentrated in June and July, and subsided by early August. The decline in movements coincided with spawning by anadromous sockeye salmon, which offer a high-quality resource pulse of food to resident species. Inter-stream movements may represent prospecting behavior as individuals seek out the most profitable foraging opportunities that are patchily distributed across space and time. Our results highlight that large-scale movements may not only be necessary for individuals to fulfill their life-cycle, but also to exploit heterogeneously spaced trophic resources. Therefore, habitat fragmentation and homogenization may have strong, but currently undescribed, ecological effects on the access to critical food resources in stream-dwelling fish populations. PMID:26379237

  2. Temporal trends and spatial patterns in nutrient export along the Mississippi River and its Tributaries

    Science.gov (United States)

    Stewart, B.; Li, L.

    2017-12-01

    The Mississippi River, the largest river in the U. S., exports excessive nutrients from the land to the sea, causing the problem of hypoxia in the Gulf of Mexico. In this research, we examined nutrient export along the Mississippi River and its tributaries to understand its trends and patterns and to identify the major factors contributing to these trends. We examined nutrient data from 1950 - 2017 for four sites along the Mississippi River and four tributary sites from the U. S. Geological Survey. The species included: total nitrogen, organic nitrogen, ammonia, nitrate, orthophosphate, and phosphorous. We analyzed the power law relationship of concentration and discharge, for which the export of nutrient species exhibited several trends. Both nitrogen (N) and phosphorous (P) species exhibited mostly chemodynamic behavior. This is in contrast to previous observations in smaller agricultural land where N and P export was mostly chemostatic with no significant change in concentration as discharge varies, suggesting possible scaling effects at different spatial scales. We also compared the average annual concentration over time at each site. The N concentration decreased from upstream to downstream, likely due to greater agricultural activities in the upstream Mississippi river and possible denitrification along the river. The N concentration also increased with time. The P species, however, fluctuated from site to site with no clear spatial patterns, but consistently exhibited higher concentrations at upstream sites with greater agricultural activities. The P species also fluctuated over time, likely due to patterns in discharge and agricultural activities. The results of this research can be further explored by calculating the total export of nutrients into the Gulf of Mexico to determine limits and drivers of nutrient export for better water management, thus helping prevent hypoxia and eutrophication within the Mississippi River basin.

  3. Importance of reservoir tributaries to spawning of migratory fish in the upper Paraná River

    Science.gov (United States)

    da Silva, P.S.; Makrakis, Maristela Cavicchioli; Miranda, Leandro E.; Makrakis, Sergio; Assumpcao, L.; Paula, S.; Dias, João Henrique Pinheiro; Marques, H.

    2015-01-01

    Regulation of rivers by dams transforms previously lotic reaches above the dam into lentic ones and limits or prevents longitudinal connectivity, which impairs access to suitable habitats for the reproduction of many migratory fish species. Frequently, unregulated tributaries can provide important habitat heterogeneity to a regulated river and may mitigate the influence of impoundments on the mainstem river. We evaluated the importance of tributaries to spawning of migratory fish species over three spawning seasons, by comparing several abiotic conditions and larval fish distributions in four rivers that are tributaries to an impounded reach of the Upper Parana River, Brazil. Our study confirmed reproduction of at least 8 long-distance migrators, likely nine, out of a total of 19 occurring in the Upper Parana River. Total larval densities and percentage species composition differed among tributaries, but the differences were not consistent among spawning seasons and unexpectedly were not strongly related to annual differences in temperature and hydrology. We hypothesize that under present conditions, densities of larvae of migratory species may be better related to efficiency of fish passage facilities than to temperature and hydrology. Our study indicates that adult fish are finding suitable habitat for spawning in tributaries, fish eggs are developing into larvae, and larvae are finding suitable rearing space in lagoons adjacent to the tributaries. Our findings also suggest the need for establishment of protected areas in unregulated and lightly regulated tributaries to preserve essential spawning and nursery habitats.

  4. Potential proliferative effect of lipopolysaccharide preconditioning on ...

    African Journals Online (AJOL)

    User

    2015-04-01

    Apr 1, 2015 ... concentrations (0.1, 0.5 and 1 µg/ml) to assess its effect on EPCs proliferation. The following genes; ... Key words: Human umbilical cord blood (hUCB), Endothelial progenitors cells (EPCs), lipopolysaccharide. (LPS), Toll-like .... detergent reagent to each well and vibration for 10 min. The absorbance (A) in ...

  5. Genetic effects and potential parents in cowpea

    Directory of Open Access Journals (Sweden)

    Francisco Tiago Cunha Dias

    2016-11-01

    Full Text Available Six cowpea genotypes and their F2 hybrid combinations were evaluated for general and specific combining ability. The Griffing’s diallel cross design, Method 2, and mixed model B were used. The genotypes and hybrids differed statistically (p <0.01 for the 10 studied traits. With regard to the general and specific combining ability, there were statistical differences at 1% probability for all traits. The presence of additive and non-additive gene effects paves the way for breeding new hybrid cultivars. However, additive gene effects were predominant in the trait expression. Genotypes CE-542, CE-954 and CE-796 were identified as the most promising of the test group for inclusion in cowpea breeding programs.

  6. Arbeitsgemeinschaft fuer die Reinhaltung der Elbe - endocrineously active substances in the Elbe, its tributaries and the North Sea; Arbeitsgemeinschaft fuer die Reinhaltung der Elbe - Endokrin wirksame Stoffe in der Elbe, in Nebenfluessen und in der Nordsee

    Energy Technology Data Exchange (ETDEWEB)

    Heemken, O.P. [GALAB, Geesthacht (Germany); Theobald, N. [Bundesamt fuer Seeschiffahrt und Hydrographie, Hamburg (Germany); Hebbel, H. [Universitaet der Bundeswehr Hamburg (Germany); Stachel, B. [Wasserguetestelle Elbe, Hamburg (Germany)

    2000-07-01

    Endocrineously active substances are discharged into surface bodies of water with communal and industrial effluents. Especially estrogenic substances like Bisphenol A, alkyl phenols and alkyl phenol ethoxylates in the Elbe and its tributaries have been neglected so far. In the context of an interdisciplinary project, chemists, biologists and mathematicians investigated the concentrations and fate of these xenoestrogens, relative potential effects of unknown water constituents and quantitative statistical mechanisms based on the available analytical findings. The contribution intends to contribute information on the pollutant situation of selected endocrineously active substances in the Elbe and its tributaries. [German] Ein relevanter Eintragspfad fuer endokrin wirksame Stoffe in die Oberflaechengewaesser sind die Abwaesser kommunaler und industrieller Klaeranlagen. Insbesondere das Vorkommen und der Verbleib von oestrogen wirkenden Stoffen wie Bisphenol A, den Alkylphenolen und Alkylphenolethoxylaten in der Elbe und in Elbenebenfluessen wurde bisher zu wenig Aufmerksamkeit geschenkt. In einem interdisziplinaeren Projekt, an dem sich Chemiker, Biologen und Mathematiker beteiligten, wird versucht, eine erste Antwort zu geben ueber das Vorkommen und den Verbleib dieser Xenooestrogene, ueber relative Wirkpotenzen von unbekannten Wasserinhaltsstoffen durch die Anwendung von In-vitro-Tests und ueber quantitative statistische Zusammenhaenge, die auf vorhandenen Analysenergebnissen basieren. Dieser Bericht soll einen Beitrag leisten zur Immissionssituation von ausgewaehlten endokrin wirksamen Stoffen in der Elbe und in Elbenebenfluessen. (orig.)

  7. Effective Kratzer and Coulomb potentials as limit cases of a multiparameter exponential-type potential

    Energy Technology Data Exchange (ETDEWEB)

    García-Ravelo, J., E-mail: g.ravelo@hotmail.com [Departamento de Física, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Edificio 9, Unidad Profesional Adolfo López Mateos, México D.F., 07738 (Mexico); Menéndez, A.; García-Martínez, J. [Departamento de Física, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Edificio 9, Unidad Profesional Adolfo López Mateos, México D.F., 07738 (Mexico); Schulze-Halberg, A. [Department of Mathematics and Actuarial Science and Department of Physics, Indiana University Northwest, 3400 Broadway, Gary, IN 46408 (United States)

    2014-06-13

    We show that the effective Kratzer and Coulomb potentials can be obtained by taking particular limits of a multiparameter exponential potential that was studied recently. Moreover, we demonstrate that the bound state solutions of the exponential potential reduce correctly to their well-known counterparts associated with the Kratzer and Coulomb potentials. As a byproduct, we obtain a new limit relation for the hypergeometric function. - Highlights: • Kratzer and Coulomb potentials are limit cases of an exponential-type potential. • From exact s-waves, approximate solutions for l-waves are obtained. • l-waves of the potential tend to the solutions of the Kratzer and Coulomb potentials. • A non-evident identity between hypergeometric functions is demonstrated.

  8. Effective Kratzer and Coulomb potentials as limit cases of a multiparameter exponential-type potential

    International Nuclear Information System (INIS)

    García-Ravelo, J.; Menéndez, A.; García-Martínez, J.; Schulze-Halberg, A.

    2014-01-01

    We show that the effective Kratzer and Coulomb potentials can be obtained by taking particular limits of a multiparameter exponential potential that was studied recently. Moreover, we demonstrate that the bound state solutions of the exponential potential reduce correctly to their well-known counterparts associated with the Kratzer and Coulomb potentials. As a byproduct, we obtain a new limit relation for the hypergeometric function. - Highlights: • Kratzer and Coulomb potentials are limit cases of an exponential-type potential. • From exact s-waves, approximate solutions for l-waves are obtained. • l-waves of the potential tend to the solutions of the Kratzer and Coulomb potentials. • A non-evident identity between hypergeometric functions is demonstrated

  9. Beyond the Coleman–Weinberg Effective Potential

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    The Two-Particle-Irreducible (2PI) formalism as introduced by Cornwall, Jackiw and Tomboulis provides a systematic analytic approach to consistently describing non-perturbative phenomena in Quantum Field Theory. In spite of its great success, one major problem of the 2PI approach is that its loopwise expansion gives rise to residual violations of symmetries and hence to massive Goldstone bosons in the spontaneously broken phase of the theory. In my talk I will present a novel symmetry-improved 2PI formalism which consistently encodes global symmetries in a loopwise expansion. Unlike other methods, I will illustrate how the symmetry-improved 2PI effective action satisfies a number of important field-theoretic properties, such as the masslessness of the Goldstone boson and the fact that the phase transition is of second order in O(N) theories, already in the Hartree-Fock approximation. After taking the sunset diagrams into account, I show how the symmetry-improved 2PI approach properly describe...

  10. Effective potential of light quark interactions at finite temperatures

    International Nuclear Information System (INIS)

    Lipskikh, S.I.

    1989-01-01

    The model of an open bosonic string with free ends is applied to construct the effective interaction potential for two light quarks at finite temperatures. This potential is shown to be a second-order potential with respect to the interquark distance

  11. Matter-wave bright solitons in effective bichromatic lattice potentials

    Indian Academy of Sciences (India)

    Matter-wave bright solitons in bichromatic lattice potentials are considered and their dynamics for different lattice environments are studied. Bichromatic potentials are created from superpositions of (i) two linear optical lattices and (ii) a linear and a nonlinear optical lattice. Effective potentials are found for the solitons in both ...

  12. Assessment of Cr pollution in tributary sediment cores in the Three Gorges Reservoir combining geochemical baseline and in situ DGT.

    Science.gov (United States)

    Gao, Bo; Gao, Li; Xu, Dongyu; Zhou, Yang; Lu, Jin

    2018-07-01

    The mobility and transfer of trace metals in sediments are vital to understanding trace metals environmental behavior in water environment. However, as a predominant aquatic carcinogen, an effective method for assessing the release and deposition for Cr at the sediment-water interface (SWI) is still not clearly understood. Here we established a comprehensive methodology to evaluate the release risk of Cr at the SWI combining regional geochemical baseline (RGB) and diffusive gradients in thin films (DGT). Sediment cores and water samples were collected in the two tributaries and mainstream of the Three Gorges Reservoir, which is the world's largest man-made hydroelectric station. Results showed that the calculated Cr carcinogenic risks in surface water did not exceed US EPA maximum recommended level. The RGB of Cr (85.53 ± 14.44 mg/kg) were calculated and the differentials between Cr concentration and RGB in surface sediments showed the average anthropogenic contribution rate was 6.03% and the upstream of Meixi River (MX-S) and mainstream were influenced by anthropogenic activities. The net diffusive flux using DGT showed that Cr in the midstream of Caotang River and MX had the potential to move upwards into the overlying water. Furthermore, combining the results of differential (Cr concentration vs. RGB) and the net flux, MX-S was the only site with a risk of Cr release. To the best of our knowledge, this study is the first attempt to combine RGB and DGT to scientifically assess metal release at SWI and provided a new perspective to comprehensively assess metal pollution in water environment. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Macroinvertebrate and organic matter export from headwater tributaries of a Central Appalachian stream

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset contains physicochemical and biological data from 12 headwater tributaries of Clemons Fork in Robinson Forest, KY. This dataset is associated with the...

  14. Review of the Distribution of the Family Gobiidae (Pisces in the Bulgarian Danube Tributaries

    Directory of Open Access Journals (Sweden)

    Velislav Y. Zarev

    2013-12-01

    Full Text Available The current study aims to give in detailed information on the actual distribution of the species from family Gobiidae in the Bulgarian Danube tributaries. All known literature has been revised and with the new data collected is given complete and actual information on their distribution. In the period 2010-2012 were sampled a total of 41 sites alongside each one of the Bulgarian Danube tributaries. The sampling started from the river mouths to upstream in order to discover what is the southern (upstream distribution of each one goby species. Four goby species were recorded from the tributaries – the round goby (Neogobius melanostomus Pallas, 1814, the monkey goby (Neogobius fluviatilis, the racer goby (Neogobius gymnotrachelus and the tubenose goby (Proterorhinus marmoratus. Further analysis showed preference of mixed substrates and silt in addition of homogenous ones. The occurrence of gobies in the studied tributaries decreased inversely proportional to distance from Danube.

  15. LBA-ECO CD-06 Outgassing of CO2 from Amazon Mainstem, Tributaries and Varzea

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides estimates of monthly carbon dioxide (CO2) flux from the Amazon mainstem rivers, tributary stream networks, and their associated...

  16. LBA-ECO CD-06 Flux of CO2 from Amazon Mainstem Rivers, Tributaries, and Floodplains

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides estimates of monthly carbon dioxide (CO2) flux from the Amazon mainstem rivers, tributary stream networks, and their associated varzeas...

  17. Membrane potential change effects on cationic and neutral drug ...

    African Journals Online (AJOL)

    Membrane potential change effects on cationic and neutral drug - induced erythrocyte shape change and cellular uptake of drugs. A Nwafor, WT Coakley. Abstract. The effect of membrane potential change of the human erythrocytes on cationic drugs tetracaine and chlorpromazine and neutral drug benzyl alcohol induced ...

  18. Potential effects of climate change on birds of the Northeast

    Science.gov (United States)

    N.L. Rodenhouse; S.N. Matthews; K.P. McFarland; J.D. Lambert; L.R. Iverson; A. Prasad; T.S. Stillett; R.T. Holmes

    2008-01-01

    We used three approaches to assess potential effects of climate change on birds of the Northeast. First, we created distribution and abundance models for common bird species using climate, elevation, and tree species variables and modeled how bird distributions might change as habitats shift. Second, we assessed potential effects on high-elevation birds, especially...

  19. Effects of Potential Lane-Changing Probability on Uniform Flow

    International Nuclear Information System (INIS)

    Tang Tieqiao; Huang Haijun; Shang Huayan

    2010-01-01

    In this paper, we use the car-following model with the anticipation effect of the potential lane-changing probability (Acta Mech. Sin. 24 (2008) 399) to investigate the effects of the potential lane-changing probability on uniform flow. The analytical and numerical results show that the potential lane-changing probability can enhance the speed and flow of uniform flow and that their increments are related to the density.

  20. Taming the Goldstone contributions to the effective potential

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Stephen P.

    2014-07-01

    The standard perturbative effective potential suffers from two related problems of principle involving the field-dependent Goldstone boson squared mass, G. First, in general G can be negative, and it actually is negative in the Standard Model; this leads to imaginary contributions to the effective potential that are not associated with a physical instability, and therefore spurious. Second, in the limit that G approaches zero, the effective potential minimization condition is logarithmically divergent already at two-loop order, and has increasingly severe power-law singularities at higher loop orders. I resolve both issues by resumming the Goldstone boson contributions to the effective potential. For the resulting resummed effective potential, the minimum value and the minimization condition that gives the vacuum expectation value are obtained in forms that do not involve G at all.

  1. Socio-economic status and environmental problems affecting the fishermen along the river tributaries of Dagupan City

    Directory of Open Access Journals (Sweden)

    Sally A. Jarin

    2018-02-01

    Full Text Available This study was conducted to determine the socio-economic status of the fishermen along the river tributaries of Dagupan City and to study the environment problems affecting the fishermen along the river tributaries of Dagupan City. This study used a mixed method research design and utilized a survey questionnaire to gather response from 60 fishers selected through proportionate sampling. The fishermen along the tributaries of Dagupan City are mostly male, young adult with family of their own, attended primary education, and belong to big family size. All respondents owned houses made only of light materials. Shrimps and crabs were the most frequently caught species now compared to many small pelagic fishes before, when there were no aquaculture structures like fish pens and cages. Fishermen were limited to the ownership of passive fishing gears like gill nets, skylab, skyblue, and liftnet. Fishpen or cage structures were owned by big businessmen while the fishers served only as caretakers. The respondents are worried on the decrease of fish catch. It is recommended that the government of the City of Dagupan should continue its program in demolishing pen and cage structures to free the rivers from pollution of feed inputs. Management and economic measures should be considered in order to gain significant effect on income of the fishermen. In designing management systems which have income improvement as a goal, appropriate implementation, monitoring and evaluation initiatives should be conducted and taken cared of for sustainable income improvement of farmers in the community of Dagupan and, perhaps, wealth distribution.

  2. Study of tributary inflows in Lake Iseo with a rotating physical model

    Directory of Open Access Journals (Sweden)

    Marco Pilotti

    2014-03-01

    Full Text Available The influence of Coriolis force on the currents of large lakes is well acknowledged; very few contributions, however, investigate this aspect in medium-size lakes where its relevance could be questionable. In order to study the area of influence of the two major tributary rivers in Lake Iseo, a rotating vertically distorted physical model of the northern part of this lake was prepared and used, respecting both Froude and Rossby similarity. The model has a horizontal length scale factor of 8000 and a vertical scale factor of 500 and was used both in homogeneous and in thermally stratified conditions. We explored the pattern of water circulation in front of the entrance mouth for different hydrologic scenarios at the beginning of spring and in summer. We neglected the influence of winds. The primary purposes of the model were twofold: i to increase our level of knowledge of the hydrodynamics of Lake Iseo by verifying the occurrence of dynamical effects related to the Earth’s rotation on the plume of the two tributaries that enter the northern part of the lake and ii to identify the areas of the lake that can be directly influenced by the tributaries’ waters, in order to provide guidance on water quality monitoring in zones of relevant environmental and touristic value. The results of the physical model confirm the relevant role played by the Coriolis force in the northern part of the lake. Under ordinary flow conditions, the model shows a systematic deflection of the inflowing waters towards the western shore of the lake. The inflow triggers a clockwise gyre within the Lovere bay, to the West of the inflow, and a slow counter-clockwise gyre, to the East of the inflow, that returns water towards the river mouth along the eastern shore. For discharges with higher return period, when only the contribution by Oglio River is relevant, the effect of the Earth’s rotation weakens in the entrance zone and the plume has a more rectilinear pattern

  3. Evaluation of Water Quality for Two St. Johns River Tributaries Receiving Septic Tank Effluent, Duval County, Florida

    Science.gov (United States)

    Wicklein, Shaun M.

    2004-01-01

    Tributary streamflow to the St. Johns River in Duval County is thought to be affected by septic tank leachate from residential areas adjacent to these tributaries. Water managers and the city of Jacksonville have committed to infrastructure improvements as part of a management plan to address the impairment of tributary water quality. In order to provide data to evaluate the effects of future remedial activities in selected tributaries, major ion and nutrient concentrations, fecal coliform concentrations, detection of wastewater compounds, and tracking of bacterial sources were used to document septic tank influences on the water quality of selected tributaries. The tributaries Fishing Creek and South Big Fishweir Creek were selected because they drain subdivisions identified as high priority locations for septic tank phase-out projects: the Pernecia and Murray Hill B subdivisions, respectively. Population, housing (number of residences), and septic tank densities for the Murray Hill B subdivision are greater than those for the Pernecia subdivision. Water-quality samples collected in the study basins indicate influences from ground water and septic tanks. Estimated concentrations of total nitrogen ranged from 0.33 to 2.86 milligrams per liter (mg/L), and ranged from less than laboratory reporting limit (0.02 mg/L) to 0.64 mg/L for total phosphorus. Major ion concentrations met the State of Florida Class III surface-water standards; total nitrogen and total phosphorus concentrations exceeded the U.S. Environmental Protection Agency Ecoregion XII nutrient criteria for rivers and streams 49 and 96 percent of the time, respectively. Organic wastewater compounds detected at study sites were categorized as detergents, antioxidants and flame retardants, manufactured polycarbonate resins, industrial solvents, and mosquito repellent. The most commonly detected compound was para-nonylphenol, a breakdown product of detergent. Results of wastewater sampling give evidence that

  4. Effective potential in Lorentz-breaking field theory models

    Energy Technology Data Exchange (ETDEWEB)

    Baeta Scarpelli, A.P. [Centro Federal de Educacao Tecnologica, Nova Gameleira Belo Horizonte, MG (Brazil); Setor Tecnico-Cientifico, Departamento de Policia Federal, Belo Horizonte, MG (Brazil); Brito, L.C.T. [Universidade Federal de Lavras, Departamento de Fisica, Lavras, MG (Brazil); Felipe, J.C.C. [Universidade Federal de Lavras, Departamento de Fisica, Lavras, MG (Brazil); Universidade Federal dos Vales do Jequitinhonha e Mucuri, Instituto de Engenharia, Ciencia e Tecnologia, Veredas, Janauba, MG (Brazil); Nascimento, J.R.; Petrov, A.Yu. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, Paraiba (Brazil)

    2017-12-15

    We calculate explicitly the one-loop effective potential in different Lorentz-breaking field theory models. First, we consider a Yukawa-like theory and some examples of Lorentz-violating extensions of scalar QED. We observe, for the extended QED models, that the resulting effective potential converges to the known result in the limit in which Lorentz symmetry is restored. Besides, the one-loop corrections to the effective potential in all the cases we study depend on the background tensors responsible for the Lorentz-symmetry violation. This has consequences for physical quantities like, for example, in the induced mass due to the Coleman-Weinberg mechanism. (orig.)

  5. Hydrologic Data for Deep Creek Lake and Selected Tributaries, Garrett County, Maryland, 2007-08

    Science.gov (United States)

    Banks, William S.L.; Davies, William J.; Gellis, Allen C.; LaMotte, Andrew E.; McPherson, Wendy S.; Soeder, Daniel J.

    2010-01-01

    Introduction Recent and ongoing efforts to develop the land in the area around Deep Creek Lake, Garrett County, Maryland, are expected to change the volume of sediment moving toward and into the lake, as well as impact the water quality of the lake and its many tributaries. With increased development, there is an associated increased demand for groundwater and surface-water withdrawals, as well as boat access. Proposed dredging of the lake bottom to improve boat access has raised concerns about the adverse environmental effects such activities would have on the lake. The Maryland Department of Natural Resources (MDDNR) and the U.S. Geological Survey (USGS) entered into a cooperative study during 2007 and 2008 to address these issues. This study was designed to address several objectives to support MDDNR?s management strategy for Deep Creek Lake. The objectives of this study were to: Determine the current physical shape of the lake through bathymetric surveys; Initiate flow and sediment monitoring of selected tributaries to characterize the stream discharge and sediment load of lake inflows; Determine sedimentation rates using isotope analysis of sediment cores; Characterize the degree of hydraulic connection between the lake and adjacent aquifer systems; and Develop an estimate of water use around Deep Creek Lake. Summary of Activities Data were collected in Deep Creek Lake and in selected tributaries from September 2007 through September 2008. The methods of investigation are presented here and all data have been archived according to USGS policy for future use. The material presented in this report is intended to provide resource managers and policy makers with a broad understanding of the bathymetry, surface water, sedimentation rates, groundwater, and water use in the study area. The report is structured so that the reader can access each topic separately using any hypertext markup (HTML) language reader. In order to establish a base-line water-depth map of

  6. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: I. Patterns of occurrence

    Science.gov (United States)

    Elliott, Sarah M.; Brigham, Mark E.; Lee, Kathy E.; Banda, Jo A.; Choy, Steven J.; Gefell, Daniel J.; Minarik, Thomas A.; Moore, Jeremy N.; Jorgenson, Zachary G.

    2017-01-01

    Human activities introduce a variety of chemicals to the Laurentian Great Lakes including pesticides, pharmaceuticals, flame retardants, plasticizers, and solvents (collectively referred to as contaminants of emerging concern or CECs) potentially threatening the vitality of these valuable ecosystems. We conducted a basin-wide study to identify the presence of CECs and other chemicals of interest in 12 U.S. tributaries to the Laurentian Great Lakes during 2013 and 2014. A total of 292 surface-water and 80 sediment samples were collected and analyzed for approximately 200 chemicals. A total of 32 and 28 chemicals were detected in at least 30% of water and sediment samples, respectively. Concentrations ranged from 0.0284 (indole) to 72.2 (cholesterol) μg/L in water and 1.75 (diphenhydramine) to 20,800 μg/kg (fluoranthene) in sediment. Cluster analyses revealed chemicals that frequently co-occurred such as pharmaceuticals and flame retardants at sites receiving similar inputs such as wastewater treatment plant effluent. Comparison of environmental concentrations to water and sediment-quality benchmarks revealed that polycyclic aromatic hydrocarbon concentrations often exceeded benchmarks in both water and sediment. Additionally, bis(2-ethylhexyl) phthalate and dichlorvos concentrations exceeded water-quality benchmarks in several rivers. Results from this study can be used to understand organism exposure, prioritize river basins for future management efforts, and guide detailed assessments of factors influencing transport and fate of CECs in the Great Lakes Basin.

  7. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: I. Patterns of occurrence.

    Directory of Open Access Journals (Sweden)

    Sarah M Elliott

    Full Text Available Human activities introduce a variety of chemicals to the Laurentian Great Lakes including pesticides, pharmaceuticals, flame retardants, plasticizers, and solvents (collectively referred to as contaminants of emerging concern or CECs potentially threatening the vitality of these valuable ecosystems. We conducted a basin-wide study to identify the presence of CECs and other chemicals of interest in 12 U.S. tributaries to the Laurentian Great Lakes during 2013 and 2014. A total of 292 surface-water and 80 sediment samples were collected and analyzed for approximately 200 chemicals. A total of 32 and 28 chemicals were detected in at least 30% of water and sediment samples, respectively. Concentrations ranged from 0.0284 (indole to 72.2 (cholesterol μg/L in water and 1.75 (diphenhydramine to 20,800 μg/kg (fluoranthene in sediment. Cluster analyses revealed chemicals that frequently co-occurred such as pharmaceuticals and flame retardants at sites receiving similar inputs such as wastewater treatment plant effluent. Comparison of environmental concentrations to water and sediment-quality benchmarks revealed that polycyclic aromatic hydrocarbon concentrations often exceeded benchmarks in both water and sediment. Additionally, bis(2-ethylhexyl phthalate and dichlorvos concentrations exceeded water-quality benchmarks in several rivers. Results from this study can be used to understand organism exposure, prioritize river basins for future management efforts, and guide detailed assessments of factors influencing transport and fate of CECs in the Great Lakes Basin.

  8. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: I. Patterns of occurrence

    Science.gov (United States)

    Lee, Kathy E.; Banda, Jo A.; Choy, Steven J.; Gefell, Daniel J.; Minarik, Thomas A.; Moore, Jeremy N.; Jorgenson, Zachary G.

    2017-01-01

    Human activities introduce a variety of chemicals to the Laurentian Great Lakes including pesticides, pharmaceuticals, flame retardants, plasticizers, and solvents (collectively referred to as contaminants of emerging concern or CECs) potentially threatening the vitality of these valuable ecosystems. We conducted a basin-wide study to identify the presence of CECs and other chemicals of interest in 12 U.S. tributaries to the Laurentian Great Lakes during 2013 and 2014. A total of 292 surface-water and 80 sediment samples were collected and analyzed for approximately 200 chemicals. A total of 32 and 28 chemicals were detected in at least 30% of water and sediment samples, respectively. Concentrations ranged from 0.0284 (indole) to 72.2 (cholesterol) μg/L in water and 1.75 (diphenhydramine) to 20,800 μg/kg (fluoranthene) in sediment. Cluster analyses revealed chemicals that frequently co-occurred such as pharmaceuticals and flame retardants at sites receiving similar inputs such as wastewater treatment plant effluent. Comparison of environmental concentrations to water and sediment-quality benchmarks revealed that polycyclic aromatic hydrocarbon concentrations often exceeded benchmarks in both water and sediment. Additionally, bis(2-ethylhexyl) phthalate and dichlorvos concentrations exceeded water-quality benchmarks in several rivers. Results from this study can be used to understand organism exposure, prioritize river basins for future management efforts, and guide detailed assessments of factors influencing transport and fate of CECs in the Great Lakes Basin. PMID:28953889

  9. The effect of membrane diffusion potential change on anionic drugs ...

    African Journals Online (AJOL)

    The effect of membrane potential change on anionic drugs Indomethacin and barbitone induced human erythrocyte shape change and red cell uptake of drug has been studied using microscopy and spectrophotometry techniques respectively. The membrane potential was changed by reducing the extracellular chloride ...

  10. Effects Of Irrigation Frequency On Soil Moisture Potential And ...

    African Journals Online (AJOL)

    Irrigation frequency affects soil properties with a residual influence on soil moisture potential, crop performance and shoot yield of vegetables. This study investigated the effect of irrigation frequency on the growth, shoot yield of large green, soil moisture potential, and soil chemical properties based on ramdomised complete ...

  11. Effects of treated poultry litter on potential greenhouse gas emission ...

    African Journals Online (AJOL)

    A study was conducted to evaluate the effects of different treatments of poultry faecal waste on potential greenhouse gas emission and inherent agronomic potentials. Sugar solution at 100g/l salt solution at 350g/l and oven-drying were the various faecal treatments examined using a completely randomized design.

  12. Directly patching high-level exchange-correlation potential based on fully determined optimized effective potentials

    Science.gov (United States)

    Huang, Chen; Chi, Yu-Chieh

    2017-12-01

    The key element in Kohn-Sham (KS) density functional theory is the exchange-correlation (XC) potential. We recently proposed the exchange-correlation potential patching (XCPP) method with the aim of directly constructing high-level XC potential in a large system by patching the locally computed, high-level XC potentials throughout the system. In this work, we investigate the patching of the exact exchange (EXX) and the random phase approximation (RPA) correlation potentials. A major challenge of XCPP is that a cluster's XC potential, obtained by solving the optimized effective potential equation, is only determined up to an unknown constant. Without fully determining the clusters' XC potentials, the patched system's XC potential is "uneven" in the real space and may cause non-physical results. Here, we developed a simple method to determine this unknown constant. The performance of XCPP-RPA is investigated on three one-dimensional systems: H20, H10Li8, and the stretching of the H19-H bond. We investigated two definitions of EXX: (i) the definition based on the adiabatic connection and fluctuation dissipation theorem (ACFDT) and (ii) the Hartree-Fock (HF) definition. With ACFDT-type EXX, effective error cancellations were observed between the patched EXX and the patched RPA correlation potentials. Such error cancellations were absent for the HF-type EXX, which was attributed to the fact that for systems with fractional occupation numbers, the integral of the HF-type EXX hole is not -1. The KS spectra and band gaps from XCPP agree reasonably well with the benchmarks as we make the clusters large.

  13. Electric potential invariants and ions-in-molecules effective potentials for molecular Rydberg states.

    Science.gov (United States)

    Coy, Stephen L; Grimes, David D; Zhou, Yan; Field, Robert W; Wong, Bryan M

    2016-12-21

    The dependence of multipole moments and polarizabilities on external fields appears in many applications including biomolecular molecular mechanics, optical non-linearity, nanomaterial calculations, and the perturbation of spectroscopic signatures in atomic clocks. Over a wide range of distances, distributed multipole and polarizability potentials can be applied to obtain the variation of atom-centered atoms-in-molecules electric properties like bonding-quenched polarizability. For cylindrically symmetric charge distributions, we examine single-center and atom-centered effective polarization potentials in a non-relativistic approximation for Rydberg states. For ions, the multipole expansion is strongly origin-dependent, but we note that origin-independent invariants can be defined. The several families of invariants correspond to optimized representations differing by origin and number of terms. Among them, a representation at the center of dipole polarizability optimizes the accuracy of the potential with terms through 1/r 4 . We formulate the single-center expansion in terms of polarization-modified effective multipole moments, defining a form related to the source-multipole expansion of Brink and Satchler. Atom-centered potentials are an origin independent alternative but are limited both by the properties allowed at each center and by the neglected effects like bond polarizability and charge flow. To enable comparisons between single-center effective potentials in Cartesian or spherical form and two-center effective potentials with differing levels of mutual induction between atomic centers, we give analytical expressions for the bond-length and origin-dependence of multipole and polarizability terms projected in the multipole and polarizability expansion of Buckingham. The atom-centered potentials can then be used with experimental data and ab initio calculations to estimate atoms-in-molecules properties. Some results are given for BaF + and HF showing the

  14. The impact of basin heterogeneity on modeling results of two tributaries of the Okavango River

    Science.gov (United States)

    Baumberg, V.; Goehmann, H.; Steudel, T.; Fluegel, W.; Helmschrot, J.

    2013-12-01

    are achieved for the Cubango River while peak flows are slightly underestimated. The model for the Cuito River simulates temporal runoff dynamics well but under- or overestimates the peaks. These varieties can be explained by insufficient information regarding the extent or structure of internal storages, e.g. groundwater aquifers or swamps in the Cuito system. However, both models provide a water balance which is in agreement to results of previous studies. Despite some discrepancies in the simulated hydrographs, both models also reflect the spatial variability of runoff generation mechanisms and, thereby, allow for a first assessment of the spatial relevance of individual runoff components for the Okavango River discharge or quantifications of soil moisture patterns and evapotranspiration. Our model results underpin that the diversity of both tributaries and particularly higher water storage capacities of the sediments, the effects of the swampy valleys and the thick layers of Kalahari sands attenuating runoff in the Cuito River need to be taken into account for a reliable modeling of the entire Okavango River basin.

  15. Assessing Microplastic Loads in the Mississippi River and Its Major Tributaries

    Science.gov (United States)

    Hasenmueller, E. A.; Martin, K. M.; Conkle, J. L.; White, J. R.

    2017-12-01

    Plastic debris is ubiquitous in marine environments and can cause significant harm to aquatic life when organisms become entangled in the plastic or mistake it for food. Macroplastic debris (plastic >5 mm in diameter) has received significant attention from the public, government agencies, and the scientific community. However, the majority of plastics in aquatic environments are microplastics (plastic Administration (NOAA) Marine Debris Program, has quantified and characterized microplastics (i.e., size, shape, and resin type) at the surface and at depth along the mainstem of the Mississippi River, including near major cities such as St. Louis and New Orleans, as well as in some of the Mississippi River's major tributaries (i.e., the Missouri River, Ohio River, and Illinois River). Sampling is ongoing, but our datasets will allow us to characterize: 1) total microplastic concentrations and loads, 2) spatial and temporal trends in microplastic abundances, and 3) land-use effects on microplastic levels across the Mississippi River watershed. Our data will also provide estimates of the total discharge of microplastics from the Mississippi River to the Gulf of Mexico. These efforts will provide a baseline for future research relating to the fate and effects of microplastics in aquatic environments and can guide federal and local policy makers in creating and assessing mitigation strategies to improve water quality.

  16. Effect of Ionic Diffusion on Extracellular Potentials in Neural Tissue.

    Directory of Open Access Journals (Sweden)

    Geir Halnes

    2016-11-01

    Full Text Available Recorded potentials in the extracellular space (ECS of the brain is a standard measure of population activity in neural tissue. Computational models that simulate the relationship between the ECS potential and its underlying neurophysiological processes are commonly used in the interpretation of such measurements. Standard methods, such as volume-conductor theory and current-source density theory, assume that diffusion has a negligible effect on the ECS potential, at least in the range of frequencies picked up by most recording systems. This assumption remains to be verified. We here present a hybrid simulation framework that accounts for diffusive effects on the ECS potential. The framework uses (1 the NEURON simulator to compute the activity and ionic output currents from multicompartmental neuron models, and (2 the electrodiffusive Kirchhoff-Nernst-Planck framework to simulate the resulting dynamics of the potential and ion concentrations in the ECS, accounting for the effect of electrical migration as well as diffusion. Using this framework, we explore the effect that ECS diffusion has on the electrical potential surrounding a small population of 10 pyramidal neurons. The neural model was tuned so that simulations over ∼100 seconds of biological time led to shifts in ECS concentrations by a few millimolars, similar to what has been seen in experiments. By comparing simulations where ECS diffusion was absent with simulations where ECS diffusion was included, we made the following key findings: (i ECS diffusion shifted the local potential by up to ∼0.2 mV. (ii The power spectral density (PSD of the diffusion-evoked potential shifts followed a 1/f2 power law. (iii Diffusion effects dominated the PSD of the ECS potential for frequencies up to several hertz. In scenarios with large, but physiologically realistic ECS concentration gradients, diffusion was thus found to affect the ECS potential well within the frequency range picked up in

  17. The effect of jogging on P300 event related potentials.

    Science.gov (United States)

    Nakamura, Y; Nishimoto, K; Akamatu, M; Takahashi, M; Maruyama, A

    1999-03-01

    Physical exercise has beneficial effects not only on cardiovascular system and fat metabolism, may also directly effect the cognitive process. We studied the effect of physical exercise on cognitive processes by measuring the P300 event related-potential (ERP) after jogging. Seven well-trained joggers were enrolled in this study and the P300 potentials using auditory oddball paradigm. ERPs were measured before and after 30 minutes of jogging. The amplitude of the P300 significantly increased after jogging compared to values recorded before jogging. These findings suggest that jogging has the effect of facilitating cognitive processes involved in generation of the P300.

  18. Effective polarization interaction potentials of the partially ionized dense plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ramazanov, T S [IETP, Al Farabi Kazakh National University, Tole Bi 96a, 050012 Almaty (Kazakhstan); Dzhumagulova, K N [IETP, Al Farabi Kazakh National University, Tole Bi 96a, 050012 Almaty (Kazakhstan); Omarbakiyeva, Yu A [IETP, Al Farabi Kazakh National University, Tole Bi 96a, 050012 Almaty (Kazakhstan); Roepke, G [Institute of Physics, University of Rostock, D-18051 Rostock (Germany)

    2006-04-28

    The effective polarization interaction potential between charged and neutral particles is considered for a partially ionized plasma. This pseudopotential is deduced taking into account quantum-mechanical effects at short distances as well as screening effects at large distances. Furthermore, a cutoff radius is obtained using a modified effective-range theory. Explicit results for parameters describing the interaction of the atom with charged particles are given.

  19. Identifying palaeo-ice-stream tributaries on hard beds: mapping glacial bedforms and erosion zones in NW Scotland

    OpenAIRE

    Bradwell, Tom

    2013-01-01

    Ice streams are fed by tributaries that can extend deep into the heart of ice sheets. These tributaries are born at onset zones — the abrupt transitions from slow sheet flow to fast streaming flow that often occur at significant topographic steps on hard beds (bedrock-dominated beds). For this reason, tributary onset zones leave only a subtle erosional geomorphic signature in the landscape record that is rarely studied. This paper examines, in detail, the geomorphic signature of ice-sheet flo...

  20. Influences of Stocking Salmon Carcass Analogs on Salmonids in Klickitat River Tributaries, 2001-2005 Completion Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zendt, Joe; Sharp, Bill (Yakama Nation Fisheries, Toppenish, WA)

    2006-09-01

    This report describes the work completed by the Yakama Nation Fisheries Program (YNFP) in the Klickitat subbasin in south-central Washington under BPA innovative project No.200105500--Influences of stocking salmon carcass analogs on salmonids in Columbia River Tributaries. Salmon carcasses historically provided a significant source of marine-derived nutrients to many stream systems in the Columbia basin, and decreased run sizes have led to a loss of this nutrient source in many streams. Partners in this project developed a pathogen-free carcass analog and stocked the analogs in streams with the following objectives: restoring food availability to streams with reduced anadromous salmon returns; mimicking the natural pathways and timing of food acquisition by salmonids; minimizing unintended negative ecological effects; and increasing the growth and survival of salmonids. In the Klickitat subbasin, carcass analogs were stocked in two streams in 2002 and 2003; a third stream was used as a control. Salmonid fish abundance, growth, and stomach contents were monitored in all three streams before and after carcass analog placement. Fish, invertebrate, and periphyton samples were also collected for stable isotope analysis (to determine if nutrients from carcass analogs were incorporated into the stream food web). Water quality samples were also collected to determine if nutrient overloading occurred in streams. Significant differences in growth were found between fish in treated and untreated stream reaches. Fish in treatment reaches exhibited higher instantaneous growth rates approximately one month after the first carcass analog stocking. Stomach contents sampling indicated that salmonid fish routinely consumed the carcass analog material directly, and that stomach fullness of fish in treatment reaches was higher than in untreated reaches in the first few weeks following carcass analog stockings. No significant differences were detected in fish abundance between

  1. Event-Related Potentials and the Stroop Effect.

    Science.gov (United States)

    Sahinoglu, Babur; Dogan, Gamze

    2016-02-01

    In this manuscript, the researches on the Event-Related Potentials (ERP) elicited by the standard Stroop effect were reviewed. For the sake of clarity, only the parts of the manuscripts that reported the standard Stroop effect - ERPs relation were taken into consideration.

  2. Event-Related Potentials and the Stroop Effect

    OpenAIRE

    Sahinoglu, Babur; Dogan, Gamze

    2016-01-01

    In this manuscript, the researches on the Event-Related Potentials (ERP) elicited by the standard Stroop effect were reviewed. For the sake of clarity, only the parts of the manuscripts that reported the standard Stroop effect - ERPs relation were taken into consideration.

  3. Effective Potential for Magnetic Resonance Measurements of Restricted Diffusion

    Directory of Open Access Journals (Sweden)

    Evren Özarslan

    2017-12-01

    Full Text Available The signature of diffusive motion on the NMR signal has been exploited to characterize the mesoscopic structure of specimens in numerous applications. For compartmentalized specimens comprising isolated subdomains, a representation of individual pores is necessary for describing restricted diffusion within them. When gradient waveforms with long pulse durations are employed, a quadratic potential profile is identified as an effective energy landscape for restricted diffusion. The dependence of the stochastic effective force on the center-of-mass position is indeed found to be approximately linear (Hookean for restricted diffusion even when the walls are sticky. We outline the theoretical basis and practical advantages of our picture involving effective potentials.

  4. Ratchet effect of the domain wall by asymmetric magnetostatic potentials

    Science.gov (United States)

    Piao, Hong-Guang; Choi, Hyeok-Cheol; Shim, Je-Ho; Kim, Dong-Hyun; You, Chun-Yeol

    2011-11-01

    We investigate a ratchet effect of magnetic domain wall motion in a ferromagnetic nanowire under AC magnetic fields using micromagnetic simulation. The ratchet effect for a transverse domain wall is achieved using an asymmetric magnetic potential generated by stray fields from non-contact trapezoidal ferromagnetic stubs near the straight nanowire. The ratchet phenomenon has been examined with various combinations of amplitude and frequency of the driving AC field. Interestingly, we find that the domain wall propagates along a preferential direction by the diode-like ratchet effect under AC field. The propagation of the domain wall strongly depends on the profile of the asymmetrical magnetic potentials and the driving AC field characteristics.

  5. An integrated model coupling open-channel flow, turbidity current and flow exchanges between main river and tributaries in Xiaolangdi Reservoir, China

    Science.gov (United States)

    Wang, Zenghui; Xia, Junqiang; Li, Tao; Deng, Shanshan; Zhang, Junhua

    2016-12-01

    The ever growing importance of sustainable management of reservoir sedimentation has promoted the development and applications of turbidity current models. However, there are few effective and practical models in literature for turbidity currents in a reservoir where the impounded area involves both the main river and its many tributaries. An integrated numerical model coupling open-channel flow, turbidity current and flow exchanges between main river and tributaries is proposed, which can simulate the complex flow and sediment transport in a reservoir where these three physical processes coexist. The model consists of two sets of governing equations for the open-channel flow and turbidity current, which are based on the modified St. Venant equations by taking into account the effect of lateral flow exchanges. These two sets of equations are solved in the finite volume method framework and the solutions are executed in an alternating calculation mode. Different methods are respectively proposed to calculate the discharge of flow exchange caused by free surface gradient and turbidity current intrusion. For the surface-gradient driven flow exchange, a storage cell method, which re-defines the relationship between water level and representative cross-sectional area, is used to update the water level at confluence. For the turbidity current intrusion, a discharge formula is proposed based on the analysis of the energy and momentum transformation in the intruding turbid water body. This formula differs from previous ones in that the effect of tributary bed slope is considered. Two events of water-sediment regulation conducted in the Xiaolangdi Reservoir in 2004 and 2006 were simulated to test the ability of this model. The predicted reservoir drawdown process, the turbidity current evolution and the sediment venting efficiency were in close agreement with the measurements. The necessity to couple the flow exchanges was demonstrated by comparing the performance of the

  6. Land Use and Water Quality Along a Mekong Tributary in Northern Lao P.D.R.

    Science.gov (United States)

    Ribolzi, Olivier; Cuny, Juliette; Sengsoulichanh, Phonexay; Mousquès, Claire; Soulileuth, Bounsamai; Pierret, Alain; Huon, Sylvain; Sengtaheuanghoung, Oloth

    2011-02-01

    Improving access to clean water has the potential to make a major contribution toward poverty reduction in rural communities of Lao P.D.R. This study focuses on stream water quality along a Mekong basin tributary, the Houay Xon that flows within a mountainous, mosaic land-use catchment of northern Lao P.D.R. To compare direct water quality measurements to the perception of water quality within the riparian population, our survey included interviews of villagers. Water quality was found to vary greatly depending on the location along the stream. Overall, it reflected the balance between the stream self-cleaning potential and human pressure on the riparian zone: (i) high bacteria and suspended load levels occurred where livestock are left to free-range within the riparian zone; (ii) very low oxygen content and high bacteriological contamination prevailed downstream from villages; (iii) high concentrations of bacteria were consistently observed along urbanized banks; (iv) low oxygen content were associated with the discharge of organic-rich wastewater from a small industrial plant; (v) very high suspended load and bacteria levels occurred during flood events due to soil erosion from steep cultivated hill slopes. Besides these human induced pollutions we also noted spontaneous enrichments in metals in wetland areas fed by dysoxic groundwater. These biophysical measurements were in agreement with the opinions expressed by the majority of the interviewees who reported poor and decreasing water quality in the Houay Xon catchment. Based on our survey, we propose recommendations to improve or maintain stream water quality in the uplands of northern Lao P.D.R.

  7. Water Quality Assessment of Danjiangkou Reservoir and its Tributaries in China

    Science.gov (United States)

    Liu, Linghua; Peng, Wenqi; Wu, Leixiang; Liu, Laisheng

    2018-01-01

    Danjiangkou Reservoir is an important water source for the middle route of the South to North Water Diversion Project in China, and water quality of Danjiangkou Reservoir and its tributaries is crucial for the project. The purpose of this study is to evaluate the water quality of Daniiangkou Reservoir and its tributaries based on Canadian Council of Ministers of the Environment Water Quality Index (CCMEWQI). 22 water quality parameters from 25 sampling sites were analyzed to calculate WQI. The results indicate that water quality in Danjiangkou Reservoir area, Hanjiang River and Danjiang River is excellent. And the seriously polluted tributary rivers were Shending River, Jianghe River, Sihe River, Tianhe River, Jianhe River and Jiangjun River. Water quality parameters that cannot meet the standard limit for drinking water source were fecal coliform bacteria, CODcr, CODMn, BOD5, NH3-N, TP, DO, anionic surfactant and petroleum. Fecal coliform bacteria, TP, ammonia nitrogen, CODMn were the most common parameters to fail.

  8. Water Quality Assessment Using Benthic Macroinvertebrates in Saigon River and Its Tributaries, Vietnam

    Directory of Open Access Journals (Sweden)

    Duc Pham Anh

    2016-06-01

    Full Text Available This study to enhance the discussion about the usefulness of benthic macroinvertebrates for water quality assessment in Saigon River and its tributaries. Data from 16 sites were used as a representative example for Saigon River and its tributaries in the area of basin over 4,500 km2, the length through provinces of Tay Ninh, Binh Phuoc, Binh Duong, and Ho Chi Minh City of about 280 km. The data covered the period of dry and rainy seasons in 2015, the survey sampled 16 sites (32 events of the Saigon River and its tributaries selected. To implement this evaluation, the analyses were based on MRC methods and classifications these improved by the scientific group.

  9. Spatial and temporal variation in recruitment and growth of Channel Catfish Alabama bass and Tallapoosa Bass in the Tallapoosa River and associated tributaries

    Science.gov (United States)

    Irwin, Elise R.; Goar, Taconya

    2015-01-01

    Effects of hydrology on growth and hatching success of age-0 black basses and Channel Catfish were examined in regulated and unregulated reaches of the Tallapoosa River, Alabama. Species of the family Centrarchidae, Ictalurus punctatus Channel Catfish and Pylodictis olivaris Flathead Catfish were also collected from multiple tributaries in the basin. Fish were collected from 2010-2014 and were assigned daily ages using otoliths. Hatch dates of individuals of three species (Micropterus henshalli Alabama Bass, M. tallapoosae Tallapoosa Bass and Channel Catfish) were back calculated, and growth histories were estimated every 5 d post hatch from otolith sections using incremental growth analysis. Hatch dates and incremental growth were related to hydrologic and temperature metrics from environmental data collected during the same time periods. Hatch dates at the regulated sites were related to and typically occurred during periods with low and stable flow conditions; however no clear relations between hatch and thermal or flow metrics were evident for the unregulated sites. Some fish hatched during unsuitable thermal conditions at the regulated site suggesting that some fish may recruit from unregulated tributaries. Ages and growth rates of age-0 black basses ranged from 105 to 131 d and 0.53 to 1.33 mm/day at the regulated sites and 44 to 128 d and 0.44 to 0.96 mm/d at the unregulated sites. In general, growth was highest among age-0 fish from the regulated sites, consistent with findings of other studies. Mortality of age-0 to age-1 fish was also variable among years and between sites and with the exception of one year, was lower at regulated sites. Multiple and single regression models of incremental growth versus age, discharge, and temperature metrics were evaluated with Akaike’s Information Criterion (AICc) to assess models that best described growth parameters. Of the models evaluated, the best overall models predicted that daily incremental growth was

  10. Presumptive Sources of Fecal Contamination in Four Tributaries to the New River Gorge National River, West Virginia, 2004

    Science.gov (United States)

    Mathes, Melvin V.; O'Brien, Tara L.; Strickler, Kriston M.; Hardy, Joshua J.; Schill, William B.; Lukasik, Jerzy; Scott, Troy M.; Bailey, David E.; Fenger, Terry L.

    2007-01-01

    Several methods were used to determine the sources of fecal contamination in water samples collected during September and October 2004 from four tributaries to the New River Gorge National River -- Arbuckle Creek, Dunloup Creek, Keeney Creek, and Wolf Creek. All four tributaries historically have had elevated levels of fecal coliform bacteria. The source-tracking methods used yielded various results, possibly because one or more methods failed. Sourcing methods used in this study included the detection of several human-specific and animal-specific biological or molecular markers, and library-dependent pulsed-field gel electrophoresis analysis that attempted to associate Escherichia coli bacteria obtained from water samples with animal sources by matching DNA-fragment banding patterns. Evaluation of the results of quality-control analysis indicated that pulsed-field gel electrophoresis analysis was unable to identify known-source bacteria isolates. Increasing the size of the known-source library did not improve the results for quality-control samples. A number of emerging methods, using markers in Enterococcus, human urine, Bacteroidetes, and host mitochondrial DNA, demonstrated some potential in associating fecal contamination with human or animal sources in a limited analysis of quality-control samples. All four of the human-specific markers were detected in water samples from Keeney Creek, a watershed with no centralized municipal wastewater-treatment facilities, thus indicating human sources of fecal contamination. The human-specific Bacteroidetes and host mitochondrial DNA markers were detected in water samples from Dunloup Creek, Wolf Creek, and to a lesser degree Arbuckle Creek. Results of analysis for wastewater compounds indicate that the September 27 sample from Arbuckle Creek contained numerous human tracer compounds likely from sewage. Dog, horse, chicken, and pig host mitochondrial DNA were detected in some of the water samples with the exception of the

  11. Additional potential effects of nuclear war on ecological systems

    International Nuclear Information System (INIS)

    Hutchinson, T.C.; Harwell, M.A.; Cropper, W.P. Jr.; Grover, H.D.

    1985-01-01

    The authors summarize biological and ecosystem responses to enhanced UV-B, air pollutants, radiation, and fire. The concentrations and biological responses associated with these perturbations are based on current experience and experimentation. Additional research is needed to quantify probable post-nuclear war exposures and potential responses. A summary is provided of all the potential effects of nuclear war on the variety of the Earth's ecosystems, including perturbations from climatic alterations, radiation, pollutants, and UV-B

  12. Effective potential of plane channeling in LiH crystal

    International Nuclear Information System (INIS)

    Korkhmazyan, N.A.; Korkhmazyan, N.N.; Babadzhanyan, N.Eh.

    2003-01-01

    The problem on determining the effective potentials of channeling along the charged planes (111) and (11-bar1) in the LiH finite crystal is considered. The criteria of the applicability of the formulae in the case of the infinite crystal are obtained. The estimate of the crystal surface layer value, wherein these formulae are not applicable, is given. In the case, when the crystal dimensions along the z-axis are much smaller, than the particle flight time, then the finite crystal potential behaves inside the crystal similarly to the infinite crystal potential [ru

  13. Occurrence and transport of diazinon in the Sacramento River, California, and selected tributaries during three winter storms, January-February 2000

    Science.gov (United States)

    Dileanis, Peter D.; Bennett, Kevin P.; Domagalski, Joseph L.

    2002-01-01

    The organophosphate pesticide diazinon is applied as a dormant orchard spray in the Sacramento Valley, California, during the winter when the area receives a majority of its annual rainfall. Dormant spray pesticides, thus, have the potential to wash off the areas of application and migrate with storm runoff to streams in the Sacramento River Basin. Previous monitoring studies have shown that rain and associated runoff from winter storms plays an important role in the transport of diazinon from point of application to the Sacramento River and tributaries. Between January 30 and February 25, 2000, diazinon concentrations in the Sacramento River and selected tributaries were monitored on 5 consecutive days during each of three winter storms that moved through the Sacramento Valley after diazinon had been applied to orchards in the basin. Water samples were collected at 17 sites chosen to represent the effect of upstream land use at local and regional scales. Most samples were analyzed using an enzyme-linked immunosorbent assay (ELISA). Analysis by gas chromatography with electron capture detector and thermionic specific detector (GC/ECD/TSD) and gas chromatography with mass spectrometry (GC/MS) was done on split replicates from over 30 percent of the samples to confirm ELISA results and to provide lower analytical reporting limits at selected sites [30 ng/L (nanogram per liter) for ELISA, 20 ng/L for GC/ECD/TSD, and 2 ng/L for GC/MS]. Concentrations determined from ELISA analyses were consistently higher than concentrations for split samples analyzed by gas chromatography methods. Because of bias between diazinon concentrations using ELISA and gas chromatography methods, results from ELISA analyses were not compared to water-quality criteria. Load calculations using the ELISA analyses are similarly biased. Because the bias was consistent, however, the ELISA data is useful in site-to-site comparisons used to rank the relative levels and contributions of diazinon from

  14. Influences of local habitat, tributary position, and dam characteristics on fish assemblages within impoundments of low-head dams in the tributaries of the Qingyi River, China.

    Science.gov (United States)

    Li, Xian; Li, Yu-Ru; Chu, Ling; Zhu, Ren; Wang, Li-Zhu; Yan, Yun-Zhi

    2016-03-18

    Low-head dam impoundments modify local habitat and alter fish assemblages; however, to our knowledge, the pattern of how fish assemblages in the impoundments relate to local habitat, tributary position, and dam characteristics is still unclear. We used data collected in 62 impoundments created by low-head dams in headwater streams of the Qingyi River, China, to examine relationships between fish assemblages and local habitat, tributary position, and dam characteristics. We also assessed the relative importance of the three groups of factors in determining fish species richness and composition. Linear regression models showed that fish species richness was related to substrate heterogeneity, confluence link, and dam number upstream. Redundancy analysis showed that fish species compositions were influenced by substrate heterogeneity, confluence link, dam height, dam numbers upstream and downstream. Overall, dam characteristics were more important in affecting fish species richness but less important in determining fish species composition than local habitat (i.e., substrate heterogeneity) and tributary position. Our results suggest that low-head dam may affect fish species richness in impoundments by modifying local habitat and constraining fish movement, and the relative abundances of those fish species may depend more on species habitat presences and stream size than on impoundment size and number.

  15. Effective potentials from complex simulations: a potential-matching algorithm and remarks on coarse-grained potentials

    International Nuclear Information System (INIS)

    Toth, Gergely

    2007-01-01

    The projection of complex interactions onto simple distance-dependent or angle-dependent classical mechanical functions is a long-standing theoretical challenge in the field of computational sciences concerning biomolecules, colloids, aggregates and simple systems as well. The construction of an effective potential may be based on theoretical assumptions, on the application of fitting procedures on experimental data and on the simplification of complex molecular simulations. Recently, a force-matching method was elaborated to project the data of Car-Parrinello ab initio molecular dynamics simulations onto two-particle classical interactions (Izvekov et al 2004 J. Chem. Phys. 120 10896). We have developed a potential-matching algorithm as a practical analogue of this force-matching method. The algorithm requires a large number of configurations (particle positions) and a single value of the potential energy for each configuration. We show the details of the algorithm and the test calculations on simple systems. The test calculation on water showed an example in which a similar structure was obtained for qualitatively different pair interactions. The application of the algorithm on reverse Monte Carlo configurations was tried as well. We detected inconsistencies in a part of our calculations. We found that the coarse graining of potentials cannot be performed perfectly both for the structural and the thermodynamic data. For example, if one applies an inverse method with an input of the pair-correlation function, it provides energetics data for the configurations uniquely. These energetics data can be different from the desired ones obtained by all atom simulations, as occurred in the testing of our potential-matching method

  16. One-loop effective potential from compactified superstring models

    International Nuclear Information System (INIS)

    Gaillard, M.K.

    1985-10-01

    A recent determination is reported of the one loop effective potential from the effective tree Lagrangian in models obtained from compactification of the zero-slope limit of superstring theories, both with and without induced terms conjectured to arise from nonperturbative effects in a hidden sector theory. In the absence of condensate effects, the vacuum structure of the tree potential is preserved by the one-loop radiative corrections. In the presence of supersymmetry breaking condensate effects at tree level, the gauge non-singlet scalars remain massless at the one-loop level. In this case the vacuum expectation value of Re t and therefore the gravitino mass are determined at one loop. Specifically, it is found that the gravitino mass, the condensate scale, and the grand unification scale must all lie within a few orders of the Planck scale. 14 refs

  17. Extreme flood estimation for a large catchment by coordinated stochastic rainfall-runoff simulations of its main tributaries

    Science.gov (United States)

    Paquet, Emmanuel

    2014-05-01

    The SCHADEX method for extreme flood estimation, proposed by Paquet et al. (2013), is a so-called "semi-continuous" stochastic simulation method in that flood events are simulated on an event basis and are superimposed on a continuous simulation of the catchment saturation hazard using rainfall-runoff modeling. A complete CDF of daily discharges and flood peak values is build up to extreme quantiles with several millions of simulated events. The application of SCHADEX to a large catchment (area greater than 5000 km²) or whose floods are affected by significant hydraulic effects (flood plains, artificial reservoir) can pose a problem with some of the hypothesis of the method (e.g. hydro-climatic homogeneity within the catchment, no significant hydraulic damping of flood peaks). To overcome this limitation, a coordinated stochastic simulation method is proposed. Firstly, several tributaries of the large catchment are selected based on their hydro-climatic features (among them homogeneity) and the availability of data. Then the main SCHADEX components are set up for these catchments (hydrological model, probabilistic model for extreme rainfall, and peak-to-volume ratio), as well as for the large one. The SCHADEX stochastic simulation is ran for the large catchment. Each randomly drawn precipitation event (at the large ctachment's scale) is disaggregated to the catchment of each tributary thanks to the observed rain field shape of an historical day of similar synoptic situation. The rain fields are reconstructed at a 1 km² resolution for the whole area thanks to the SPAZM method (Gottardi, 2012). The synoptic situations are characterized thanks to a rainfall-oriented classification (Garavaglia, 2010). For a given precipitation event, all the catchment's saturations (and snowpack conditions) are kept synchronous by superimposing the simulated event on the conditions of the same day for all catchments. Several millions of flood events are simulated this way. At the end

  18. Potentials for food waste minimization and effects on potential biogas production through anaerobic digestion.

    Science.gov (United States)

    Schott, Anna Bernstad Saraiva; Vukicevic, Sanita; Bohn, Irene; Andersson, Tova

    2013-08-01

    Several treatment alternatives for food waste can result in both energy and nutrient recovery, and thereby potential environmental benefits. However, according to the European Union waste management hierarchy, waste prevention should be the prioritized strategy to decrease the environmental burdens from all solid waste management. The aim of the present study was therefore to investigate the potential for food waste minimization among Swedish households through an investigation of the amount of avoidable food waste currently disposed of. A further aim was to investigate the effect on the national biogas production potential through anaerobic digestion of food waste, considering minimization potentials. A method for waste composition analyses of household food waste, where a differentiation between avoidable and unavoidable food waste is made, was used in a total of 24 waste composition analyses of household waste from Swedish residential areas. The total household food waste generation reached 3.4 kg (household and week)(-1), on average, of which 34% is avoidable. The theoretical methane (CH4) potential in unavoidable food waste reached 442 Ndm(3) (kg VS)(-1) or 128 Nm(3) tonne(-1) wet waste, while the measured (mesophilic CH4 batch tests) CH4 production reached 399 Ndm(3) (kg VS)(-1), which is lower than several previous assessments of CH4 production from household food waste. According to this study the combination of a decrease in food waste generation-in case of successful minimization-and decreased CH4 production from unavoidable food waste will thus result in lower total potential energy recovery from household food waste through anaerobic digestion CH4 potential than previously stated.

  19. Exact RG invariance and symmetry improved 2PI effective potential

    Directory of Open Access Journals (Sweden)

    Apostolos Pilaftsis

    2017-07-01

    Full Text Available The Symmetry Improved Two-Particle-Irreducible (SI2PI formalism is a powerful tool to calculate the effective potential beyond perturbation theory, whereby infinite sets of selective loop-graph topologies can be resummed in a systematic and consistent manner. In this paper we study the Renormalization-Group (RG properties of this formalism, by proving for the first time a number of new field-theoretic results. First, the RG runnings of all proper 2PI couplings are found to be UV finite, in the Hartree–Fock and sunset approximations of the 2PI effective action. Second, the SI2PI effective potential is exactly RG invariant, in contrast to what happens in the ordinary One-Particle-Irreducible (1PI perturbation theory, where the effective potential is RG invariant only up to higher orders. Finally, we show how the effective potential of an O(2 theory evaluated in the SI2PI framework, appropriately RG improved, can reach a higher level of accuracy, even up to one order of magnitude, with respect to the corresponding one obtained in the 1PI formalism.

  20. Effects of nonlocal potentials on (p ,d ) transfer reactions

    Science.gov (United States)

    Ross, A.; Titus, L. J.; Nunes, F. M.; Mahzoon, M. H.; Dickhoff, W. H.; Charity, R. J.

    2015-10-01

    Background: Although local phenomenological optical potentials have been standardly used to interpret nuclear reactions, recent studies suggest the effects of nonlocality should not be neglected. Purpose: In this work we investigate the effects of nonlocality in (p ,d ) transfer reactions using nonlocal optical potentials. We compare results obtained with the dispersive optical model to those obtained using the Perey-Buck interaction. Method: We solve the scattering and bound-state equations for the nonlocal version of the dispersive optical model. Then, using the distorted-wave Born approximation, we calculate the transfer cross section for (p ,d ) on 40Ca at Ep=20 , 35, and 50 MeV. Results: The inclusion of nonlocality in the bound state has a larger effect than that in the scattering states. The overall effect on the transfer cross section is very significant. We found an increase due to nonlocality in the transfer cross section of ≈30 - 50 % when using the Perey-Buck interaction and of ≈15 - 50 % when using the dispersive optical potential. Conclusions: Although the details of the nonlocal interaction can change the magnitude of the effects, our study shows that qualitatively the results obtained using the dispersive optical potential and the Perey-Buck interaction are consistent, in both cases the transfer cross sections are significantly increased.

  1. Potential beneficial effects of butyrate in intestinal and extraintestinal diseases

    Science.gov (United States)

    Canani, Roberto Berni; Costanzo, Margherita Di; Leone, Ludovica; Pedata, Monica; Meli, Rosaria; Calignano, Antonio

    2011-01-01

    The multiple beneficial effects on human health of the short-chain fatty acid butyrate, synthesized from non-absorbed carbohydrate by colonic microbiota, are well documented. At the intestinal level, butyrate plays a regulatory role on the transepithelial fluid transport, ameliorates mucosal inflammation and oxidative status, reinforces the epithelial defense barrier, and modulates visceral sensitivity and intestinal motility. In addition, a growing number of studies have stressed the role of butyrate in the prevention and inhibition of colorectal cancer. At the extraintestinal level, butyrate exerts potentially useful effects on many conditions, including hemoglobinopathies, genetic metabolic diseases, hypercholesterolemia, insulin resistance, and ischemic stroke. The mechanisms of action of butyrate are different; many of these are related to its potent regulatory effects on gene expression. These data suggest a wide spectrum of positive effects exerted by butyrate, with a high potential for a therapeutic use in human medicine. PMID:21472114

  2. Effect of ionizing radiation on transmembrane potential of Streptococcus

    International Nuclear Information System (INIS)

    Fomenko, B.S.; Akoev, I.G.

    1979-01-01

    Treatment of Streptococcus faecalis with ionizing radiation at doses of 5 to 100 krad is shown to reduce the energy-dependent accumulation of dibenzyldimethylammonium (DDA + ) by the cell. Since transmembrane potential is the moving force of DDA + transport across the membrane, the decrease in DDA + accumulation is suggested to be due to potential reduction. This radiation effect was not due to inactivation of the potential-generating mechanism; thus, the ATPase activity and glycolytic activity of the irradiated cells were higher than in the control. At the same time, the membranes exhibited an increased permeability for K + and protons, which is probably due to structural rearrangements in the membranes after irradiation. It is suggested that the potential reduction results from the increase in proton permeability of membranes

  3. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Blazer, Vicki S., E-mail: Vblazer@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Pinkney, Alfred E., E-mail: Fred_Pinkeny@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Jenkins, Jill A., E-mail: jenkinsj@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Iwanowicz, Luke R., E-mail: Liwanowicz@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Minkkinen, Steven, E-mail: steve_minkkinen@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Draugelis-Dale, Rassa O., E-mail: daler@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Uphoff, James H., E-mail: juphoff@dnr.state.md.us [Maryland Department of Natural Resources, Fisheries Service, Cooperative Oxford Laboratory, 904 South Morris Street, Oxford, MD 21654 (United States)

    2013-03-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed

  4. Potential Neuroprotective Effects of Adiponectin in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Roy Chun-Laam Ng

    2017-03-01

    Full Text Available The adipocyte-secreted protein adiponectin (APN has several protective functions in the peripheral tissues including insulin sensitizing, anti-inflammatory and anti-oxidative effects that may benefit neurodegenerative diseases such as Alzheimer’s disease (AD. In addition, dysregulation of cerebral insulin sensitivities and signaling activities have been implicated in AD. Emerging insights into the mechanistic roles of adiponectin and AD highlight the potential therapeutic effects for AD through insulin signaling.

  5. Additional factors of nuclear war potential effect on ecosystems

    International Nuclear Information System (INIS)

    Khatchinson, T.; Kharuehll, M.; Kropper, U.; Grover, G.

    1988-01-01

    Available information on response of organisms and ecosystems to increase of ultraviolet radiation, air borne pollutant concentrations, radiation and fires in case of nuclear war is generalized. The presented data are based on accumulated experience and experimental investigations. Potentiality of arising a great amount of stress effect localized regions is noted. Severe consequences for agriculture and population, particularly in sinergic stress effect, are not excluded. 169 refs.; 5 figs.; 25 tabs

  6. One-loop effective potential on hyperbolic manifolds

    International Nuclear Information System (INIS)

    Cognola, G.; Kirsten, K.; Zerbini, S.

    1993-01-01

    The one-loop effective potential for a scalar field defined on an ultrastatic space-time whose spatial part is a compact hyperbolic manifold is studied using ζ-function regularization for the one-loop effective action. Other possible regularizations are discussed in detail. The renormalization group equations are derived, and their connection with the conformal anomaly is pointed out. The symmetry breaking and the topological mass generation are also discussed

  7. String effective actions and cosmological stability of scalar potentials

    CERN Document Server

    García-Bellido, J; Garcia-Bellido, Juan; Quiros, Mariano

    1992-01-01

    The cosmology of the string effective action, including one loop string threshold corrections, is analyzed for static compactifications. The stability of the minima of a general supersymmetry breaking potential is studied in the presence of radiation. In particular, it is shown that the radiation bath makes the minima with negative cosmological constant unstable.

  8. Potential effects of chlorogenic acids on platelet activiation

    Science.gov (United States)

    Coffee (Coffea sp) is a most consumed beverage world-wide. Chlorogenic acids (CHAs) are naturally occurring phenolic acid esters abundantly found in coffee. They are reported to have potential health effects on several chronic diseases such as obesity, diabetes and cardiovascular diseases (CVD). At...

  9. Vortex lattice mobility and effective pinning potentials in the peak ...

    Indian Academy of Sciences (India)

    In that region of field and temperature the mobility of the vortex lattice (VL) is found to be dependent on the dynamical history. Recently we reported evidence that the VL reorganizes and accesses to robust VL configurations (VLCs) with different effective pinning potential wells arising in response to different system histories.

  10. Potential allelopathic effects of sunflower ( Helianthus annuus L. ) on ...

    African Journals Online (AJOL)

    Potential allelopathic effects of sunflower (Helianthus annuus L.) cultivar Hysun 38 on Rhizobium, Azospirillum, and phosphate-solubilizing bacteria (PSB) were studied by applying oxidase, QTS tests and Gram staining. Microorganisms for the control group were isolated from soil sampled before sowing sunflower.

  11. Examining triclosan-induced potentiation of the estrogen uterotrophic effect

    Science.gov (United States)

    Triclosan (TCS), a widely used antibacterial, has been shown to be an endocrine disruptor. We reported previously that TCS potentiated the estrogenic effect of ethinyl estradiol (EE) on uterine growth in rats orally administered 3 μg/kg EE and TCS (2 to 18 mg/kg) in the utero...

  12. Potential protective effect of some plant extracts against carbon ...

    African Journals Online (AJOL)

    Potential protective effect of some plant extracts against carbon tetrachloride – induced hepatotoxicity. ... Unsaturated sterols and/or triterpenes, tannins, flavonoids and carbohydrates and/or glycosides were the major active constituents of the tested plants. Keywords: hepatoprotective, medicinal plants, Plantago major, ...

  13. Linking flow, water quality and potential effects on aquatic biota ...

    African Journals Online (AJOL)

    Linking the potential effects of altered water quality on aquatic biota, that may result from a change in the flow (discharge) regime, is an essential step in the maintenance of riverine ecological functioning. Determination of the environmental flow requirement of a river (as well as other activities, such as classifying the ...

  14. membrane potential change effects on cationic and neutral drug

    African Journals Online (AJOL)

    USER

    NWAFOR A AND COAKLEY W. T. 1Department of Human Physiology, College of Health Sciences University Of Port Harcourt,. Nigeria. 2School of Pure and Applied Biology University of Wales, College of Cardiff, Cathay's Park,. Cardiff, U.K.. The effect of membrane potential change of the human erythrocytes on cationic ...

  15. The effects of water potential on some microbial populations and ...

    African Journals Online (AJOL)

    The effects of water potential on some microbial populations and decrease kinetic of organic carbon in soil treated with cow manure under laboratory conditions. ... Fourth irrigation treatment was drying-rewetting cycle (D-W) between -0.3 to -15 bars. After 0, 10, 20, 40, 60 and 90 days of incubation, soils were sampled for ...

  16. Vortex lattice mobility and effective pinning potentials in the peak

    Indian Academy of Sciences (India)

    In that region of field and temperature the mobility of the vortex lattice (VL) is found to be dependent on the dynamical history. Recently we reported evidence that the VL reorganizes and accesses to robust VL configurations (VLCs) with different effective pinning potential wells arising in response to different system histories.

  17. Effects of treated poultry litter on potential Greenhouse Gas ...

    African Journals Online (AJOL)

    This study examined the effects of different treatments of poultry faecal matter on potential greenhouse gas emission and its field application. Poultry litters were randomly assigned to four treatments viz; salt solution, alum, air exclusion and the control (untreated). Alum treated faeces had higher (p<0.05) percentage nitrogen ...

  18. Timing, frequency and environmental conditions associated with mainstem-tributary movement by a lowland river fish, golden perch (Macquaria ambigua.

    Directory of Open Access Journals (Sweden)

    Wayne M Koster

    Full Text Available Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007-2011. Fish were tagged and released in autumn 2007-2009 in the mid-Murray (n = 42 and lower Goulburn (n = 37 rivers within 3-6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem-tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem-tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers.

  19. Approaches to restoration of oak forests on farmed lowlands of the Mississippi River and its tributaries

    Science.gov (United States)

    Emile S. Gardiner; Daniel C. Dey; John A. Stanturf; Brian Roy. Lockhart

    2010-01-01

    The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More...

  20. Anthropogenic impacts on American eel demographics in Hudson River tributaries, New York

    Science.gov (United States)

    Machut, L.S.; Limburg, K.E.; Schmidt, R.E.; Dittman, D.

    2007-01-01

    Populations of American eel Anguilla rostrata along the eastern coast of North America have declined drastically for largely unknown reasons. We examined the population dynamics of American eels in six tributaries of the Hudson River, New York, to quantify their distribution and the impacts of anthropogenic stressors. With up to 155 American eels per 100 m2, tributary densities are greater than those within the main stem of the Hudson River and are among the highest reported anywhere. The predominance of small American eels (natural and artificial barriers, American eel densities were reduced by at least a factor of 10 and condition, as measured by mass, was significantly lower. Significantly lower American eel condition was also found with increasing riparian urbanization. Density-dependent growth limitations below barriers are suggested by increased growth rates above the first tributary barrier. We suggest that (1) tributaries are important habitat for the conservation of American eels and (2) mitigation of anthropogenic stressors is vital for complete utilization of available habitat and conservation of the species. ?? Copyright by the American Fisheries Society 2007.

  1. 75 FR 40034 - Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek, Clear Creek, Boone, Fort...

    Science.gov (United States)

    2010-07-13

    ... TENNESSEE VALLEY AUTHORITY Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek...-managed public land on Beaver Creek, Clear Creek, Boone, Fort Patrick Henry, South Holston, Watauga, and.... Watauga and Wilbur reservoirs are along the Watauga River. Beaver Creek and Clear Creek reservoirs are on...

  2. Electronic structure of molecules using relativistic effective core potentials

    International Nuclear Information System (INIS)

    Hay, P.J.

    1981-01-01

    Starting with one-component Cowan-Griffin relativistic Hartree-Fock orbitals, which successfully incorporate the mass-velocity and Darwin terms present in more complicated wavefunctions such as Dirac-Hartree-Fock, one can derive relativistic effective core potentials (RECP's) to carry out molecular calculations. These potentials implicitly include the dominant relativistic terms for molecules while allowing one to use the traditional quantum chemical techniques for studying the electronic structure of molecules. The effects of spin-orbit coupling can then be included using orbitals from such calculations using an effective 1-electron, 1-center spin-orbit operator. Applications to molecular systems involving heavy atoms, show good agreement with available spectroscopic data on molecular geometries and excitation energies

  3. Importance of measuring discharge and sediment transport in lesser tributaries when closing sediment budgets

    Science.gov (United States)

    Griffiths, Ronald E.; Topping, David J.

    2017-11-01

    Sediment budgets are an important tool for understanding how riverine ecosystems respond to perturbations. Changes in the quantity and grain size distribution of sediment within river systems affect the channel morphology and related habitat resources. It is therefore important for resource managers to know if a river reach is in a state of sediment accumulation, deficit or stasis. Many sediment-budget studies have estimated the sediment loads of ungaged tributaries using regional sediment-yield equations or other similar techniques. While these approaches may be valid in regions where rainfall and geology are uniform over large areas, use of sediment-yield equations may lead to poor estimations of loads in regions where rainfall events, contributing geology, and vegetation have large spatial and/or temporal variability. Previous estimates of the combined mean-annual sediment load of all ungaged tributaries to the Colorado River downstream from Glen Canyon Dam vary by over a factor of three; this range in estimated sediment loads has resulted in different researchers reaching opposite conclusions on the sign (accumulation or deficit) of the sediment budget for particular reaches of the Colorado River. To better evaluate the supply of fine sediment (sand, silt, and clay) from these tributaries to the Colorado River, eight gages were established on previously ungaged tributaries in Glen, Marble, and Grand canyons. Results from this sediment-monitoring network show that previous estimates of the annual sediment loads of these tributaries were too high and that the sediment budget for the Colorado River below Glen Canyon Dam is more negative than previously calculated by most researchers. As a result of locally intense rainfall events with footprints smaller than the receiving basin, floods from a single tributary in semi-arid regions can have large (≥ 10 ×) differences in sediment concentrations between equal magnitude flows. Because sediment loads do not

  4. Importance of measuring discharge and sediment transport in lesser tributaries when closing sediment budgets

    Science.gov (United States)

    Griffiths, Ronald; Topping, David

    2017-01-01

    Sediment budgets are an important tool for understanding how riverine ecosystems respond to perturbations. Changes in the quantity and grain size distribution of sediment within river systems affect the channel morphology and related habitat resources. It is therefore important for resource managers to know if a river reach is in a state of sediment accumulation, deficit or stasis. Many sediment-budget studies have estimated the sediment loads of ungaged tributaries using regional sediment-yield equations or other similar techniques. While these approaches may be valid in regions where rainfall and geology are uniform over large areas, use of sediment-yield equations may lead to poor estimations of loads in regions where rainfall events, contributing geology, and vegetation have large spatial and/or temporal variability.Previous estimates of the combined mean-annual sediment load of all ungaged tributaries to the Colorado River downstream from Glen Canyon Dam vary by over a factor of three; this range in estimated sediment loads has resulted in different researchers reaching opposite conclusions on the sign (accumulation or deficit) of the sediment budget for particular reaches of the Colorado River. To better evaluate the supply of fine sediment (sand, silt, and clay) from these tributaries to the Colorado River, eight gages were established on previously ungaged tributaries in Glen, Marble, and Grand canyons. Results from this sediment-monitoring network show that previous estimates of the annual sediment loads of these tributaries were too high and that the sediment budget for the Colorado River below Glen Canyon Dam is more negative than previously calculated by most researchers. As a result of locally intense rainfall events with footprints smaller than the receiving basin, floods from a single tributary in semi-arid regions can have large (≥ 10 ×) differences in sediment concentrations between equal magnitude flows. Because sediment loads do not

  5. PRODUCTION POTENTIAL AND AGRICULTURAL EFFECTIVENESS IN EUROPEAN UNION COUNTRIES

    Directory of Open Access Journals (Sweden)

    Agnieszka Baer-Nawrocka

    2013-09-01

    Full Text Available The aim of the paper was to assess the relation between agricultural production factors and effectiveness in European Union’s agriculture. For each country two synthetic coefficients were calculated using TOPSIS method. The first one characterises production factors relations, the latter one displays effectiveness of production factors. The objective of the research was to verify the correlation between these indices. The analysis proved that in many analysed countries the agricultural potential is correlated positively with the agricultural effectiveness

  6. Interaction potentials and their effect on crystal nucleation and symmetry

    International Nuclear Information System (INIS)

    Hsu, C.S.; Rahman, A.

    1979-01-01

    Molecular dynamics technique has been used to study the effect of the interaction potential on crystal nucleation and the symmetry of the nucleated phase. Four systems, namely rubidium, Lennard-Jones, rubidium-truncated, and Lennard-Jones-truncated, have been studied each at reduced density 0.95. Two types of calculations were performed. Firstly, starting from a liquid state, each system was quenched rapidly to a reduced temperature of approx.0.1. The nucleation process for these systems was monitored by studying the time dependence of temperature and the pair correlation function, and the resulting crystalline structure analyzed using among other properties the Voronoi polyhedra. Only in the case of rubidium was a b.c.c. structure nucleated. In the other three cases we obtained a f.c.c. ordering. Secondly, we have studied the effect of changing the interaction potential in a system which has already achieved an ordered state under the action of some other potential. After establishing a b.c.c. structure in a rubidium system, the change in the symmetry of the system was studied when the pair potential was modified to one of the other three forms. The results from both types of calculations are consistent: the rubidium potential leads to a b.c.c. structure while the other three potentials give an f.c.c. structure. Metastable disordered structures were not obtained in any of the calculations. However, the time elapse between the moment when the system is quick-quenched and the moment when nucleation occurs appears to depend upon the potential of interaction

  7. Molecular electrostatic potential at the atomic sites in the effective core potential approximation.

    Science.gov (United States)

    Lesiuk, Michał; Zachara, Janusz

    2013-02-21

    Considering calculations of the molecular electrostatic potential at the atomic sites (MEP@AS) in the presence of effective core potentials (ECP), we found that the consequent use of the definition of MEP@AS based on the energy derivative with respect to nuclear charge leads to a formula that differs by one term from the result of simple application of Coulomb's law. We have developed a general method to analytically treat derivatives of ECP with respect to nuclear charge. Benchmarking calculations performed on a set of simple molecules show that our formula leads to a systematic decrease in the error connected with the introduction of ECP when compared to all-electron results. Because of a straightforward implementation and relatively low costs of the developed procedure we suggest to use it by default.

  8. Comparison of potential models through heavy quark effective theory

    International Nuclear Information System (INIS)

    Amundson, J.F.

    1995-01-01

    I calculate heavy-light decay constants in a nonrelativistic potential model. The resulting estimate of heavy quark symmetry breaking conflicts with similar estimates from lattice QCD. I show that a semirelativistic potential model eliminates the conflict. Using the results of heavy quark effective theory allows me to identify and compensate for shortcomings in the model calculations in addition to isolating the source of the differences in the two models. The results lead to a rule as to where the nonrelativistic quark model gives misleading predictions

  9. Towards a Kohn-Sham potential via the optimized effective-potential method

    International Nuclear Information System (INIS)

    Norman, M.R.; Koelling, D.D.

    1984-01-01

    The optimized effective-potential (OEP) method is applied to a self-interaction-corrected local-spin-density (SIC-LSD) energy functional. The local potential which results has the useful properties of being both self-interaction free and orbital independent, and it can thus be regarded as a good approximation to the exact Kohn-Sham potential. A number of atomic systems are examined in the exchange-only and in the Ceperley-Alder exchange-correlation approximations. The resulting total energies are very close to those obtained by previous applications of the LSD-SIC functional. The resultant potentials are structurally similar to those derived by applying the OEP method to a Hartree-Fock Hamiltonian: showing much improved behavior over the local-spin-density approximation in both large- and small-r regions as well as the characteristic intershell cusplike structure. The eigenvalues have less formal significance than the more standard approaches, especially those for unoccupied orbitals which seem to have no significance whatsoever. Nonetheless, the highest occupied eigenvalue agrees closely with the conventional LSD-SIC value. However, for the deeper levels, each eigenvalue lies higher than the comparable eigenvalue of the conventional SIC, although lower than the eigenvalue of the LSD potential: the deeper the level, the larger the difference. This property follows from the nonvariational character of the eigenvalues, and it is shown that one can obtain realistic excitation spectra from this formalism by utilizing the appropriate variational quantity. The results obtained illustrate some of the less understood issues in the application of the Kohn-Sham procedure within density-functional theory

  10. Music listening after stroke: beneficial effects and potential neural mechanisms.

    Science.gov (United States)

    Särkämö, Teppo; Soto, David

    2012-04-01

    Music is an enjoyable leisure activity that also engages many emotional, cognitive, and motor processes in the brain. Here, we will first review previous literature on the emotional and cognitive effects of music listening in healthy persons and various clinical groups. Then we will present findings about the short- and long-term effects of music listening on the recovery of cognitive function in stroke patients and the underlying neural mechanisms of these music effects. First, our results indicate that listening to pleasant music can have a short-term facilitating effect on visual awareness in patients with visual neglect, which is associated with functional coupling between emotional and attentional brain regions. Second, daily music listening can improve auditory and verbal memory, focused attention, and mood as well as induce structural gray matter changes in the early poststroke stage. The psychological and neural mechanisms potentially underlying the rehabilitating effect of music after stroke are discussed. © 2012 New York Academy of Sciences.

  11. Substitutional potential of mephedrone: an analysis of the subjective effects.

    Science.gov (United States)

    Kapitány-Fövény, Máté; Kertész, Máté; Winstock, Adam; Deluca, Paolo; Corazza, Ornella; Farkas, Judit; Zacher, Gábor; Urbán, Róbert; Demetrovics, Zsolt

    2013-07-01

    In the past 25-30 years, a large number of synthetic and non-synthetic drugs have appeared on the recreational scene, but with the exception of 4-methylmethcathinone (mephedrone), none of these substances reached the popularity of ecstasy [3,4-methylenedioxy-N-methylamphetamine, (MDMA)]. Authors aimed to determine the subjective effects of mephedrone in order to understand how mephedrone can serve as a potential substitute for entactogens, such as MDMA. One hundred forty-five mephedrone users--recruited by snowball method--filled out a questionnaire on their patterns of use and experienced subjective effects of mephedrone. Factor analysis revealed six factors of mephedrone-induced subjective effects: positive emotions, sensibility, adverse somatic effects, adverse psychological effects, stimulant effects, and psychedelic effects. A preference list of subjective effects indicates that mephedrone is popular primarily for its psychostimulant and entactogen effects. Latent class analysis identified two classes of mephedrone users, with closely parallel profiles. The two classes differed in severity of subjective experience in a way that was consistent across the six dimensions. By having similar subjective effects as MDMA and other entactogens, mephedrone seems able to substitute other enactogenic stimulants. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Viruses and bacteria in floodplain lakes along a major Amazon tributary respond to distance to the Amazon River.

    Science.gov (United States)

    Almeida, Rafael M; Roland, Fábio; Cardoso, Simone J; Farjalla, Vinícius F; Bozelli, Reinaldo L; Barros, Nathan O

    2015-01-01

    In response to the massive volume of water along the Amazon River, the Amazon tributaries have their water backed up by 100s of kilometers upstream their mouth. This backwater effect is part of the complex hydrodynamics of Amazonian surface waters, which in turn drives the variation in concentrations of organic matter and nutrients, and also regulates planktonic communities such as viruses and bacteria. Viruses and bacteria are commonly tightly coupled to each other, and their ecological role in aquatic food webs has been increasingly recognized. Here, we surveyed viral and bacterial abundances (BAs) in 26 floodplain lakes along the Trombetas River, the largest clear-water tributary of the Amazon River's north margin. We correlated viral and BAs with temperature, pH, dissolved inorganic carbon, dissolved organic carbon (DOC), phosphorus, nitrogen, turbidity, water transparency, partial pressure of carbon dioxide (pCO2), phytoplankton abundance, and distance from the lake mouth until the confluence of the Trombetas with the Amazon River. We hypothesized that both bacterial and viral abundances (VAs) would change along a latitudinal gradient, as the backwater effect becomes more intense with increased proximity to the Amazon River; different flood duration and intensity among lakes and waters with contrasting sources would cause spatial variation. Our measurements were performed during the low water period, when floodplain lakes are in their most lake-like conditions. Viral and BAs, DOC, pCO2, and water transparency increased as distance to the Amazon River increased. Most viruses were bacteriophages, as viruses were strongly linked to bacteria, but not to phytoplankton. We suggest that BAs increase in response to DOC quantity and possibly quality, consequently leading to increased VAs. Our results highlight that hydrodynamics plays a key role in the regulation of planktonic viral and bacterial communities in Amazonian floodplain lakes.

  13. Ketamine for Pain Management-Side Effects & Potential Adverse Events.

    Science.gov (United States)

    Allen, Cheryl A; Ivester, Julius R

    2017-12-01

    An old anesthetic agent, ketamine is finding new use in lower doses for analgesic purposes. There are concerns stemming from its potential side effects-specifically psychomimetic effects. These side effects are directly related to dose amount. The doses used for analgesic purposes are much lower than those used for anesthesia purposes. A literature review was performed to ascertain potential side effects and/or adverse events when using ketamine for analgesia purposes. The search included CINAHL, PubMed, and Ovid using the search terms "ketamine," "ketamine infusion," "pain," "adverse events," "practice guideline," and "randomized controlled trial." Searches were limited to full-text, peer-reviewed articles and systematic reviews. Initially 1,068 articles were retrieved. The search was then narrowed by using the Boolean connector AND with various search term combinations. After adjusting for duplication, article titles and abstracts were reviewed, leaving 25 articles for an in-depth analysis. Specific exclusion criteria were then applied. The literature supports the use of ketamine for analgesic purposes, and ketamine offers a nonopioid option for the management of some pain conditions. Because ketamine is still classified as an anesthetic agent, health care institutions should develop their own set of policies and protocols for the administration of ketamine. By using forethought and understanding of the properties of ketamine, appropriate care may be planned to mitigate potential side effects and adverse events so that patients are appropriately cared for and their pain effectively managed. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  14. ${ \\mathcal P }{ \\mathcal T }$-symmetric interpretation of unstable effective potentials

    CERN Document Server

    Bender, Carl M.; Mavromatos, Nick E.; Sarkar, Sarben

    2016-01-01

    The conventional interpretation of the one-loop effective potentials of the Higgs field in the Standard Model and the gravitino condensate in dynamically broken supergravity is that these theories are unstable at large field values. A ${ \\mathcal P }{ \\mathcal T }$-symmetric reinterpretation of these models at a quantum-mechanical level eliminates these instabilities and suggests that these instabilities may also be tamed at the quantum-field-theory level.

  15. Assessment of potential effects of water produced from coalbed natural gas development on macroinvertebrate and algal communities in the Powder River and Tongue River, Wyoming and Montana, 2010

    Science.gov (United States)

    Peterson, David A.; Hargett, Eric G.; Feldman, David L.

    2011-01-01

    Ongoing development of coalbed natural gas in the Powder River structural basin in Wyoming and Montana led to formation of an interagency aquatic task group to address concerns about the effects of the resulting production water on biological communities in streams of the area. Ecological assessments, made from 2005–08 under the direction of the task group, indicated biological condition of the macroinvertebrate and algal communities in the middle reaches of the Powder was lower than in the upper or lower reaches. On the basis of the 2005–08 results, sampling of the macroinvertebrate and algae communities was conducted at 18 sites on the mainstem Powder River and 6 sites on the mainstem Tongue River in 2010. Sampling-site locations were selected on a paired approach, with sites located upstream and downstream of discharge points and tributaries associated with coalbed natural gas development. Differences in biological condition among site pairs were evaluated graphically and statistically using multiple lines of evidence that included macroinvertebrate and algal community metrics (such as taxa richness, relative abundance, functional feeding groups, and tolerance) and output from observed/expected (O/E) macroinvertebrate models from Wyoming and Montana. Multiple lines of evidence indicated a decline in biological condition in the middle reaches of the Powder River, potentially indicating cumulative effects from coalbed natural gas discharges within one or more reaches between Flying E Creek and Wild Horse Creek in Wyoming. The maximum concentrations of alkalinity in the Powder River also occurred in the middle reaches. Biological condition in the upper and lower reaches of the Powder River was variable, with declines between some site pairs, such as upstream and downstream of Dry Fork and Willow Creek, and increases at others, such as upstream and downstream of Beaver Creek. Biological condition at site pairs on the Tongue River showed an increase in one case

  16. Paleospring tufa deposition in the Kurkur Oasis region and implications for tributary integration with the River Nile in southern Egypt

    Science.gov (United States)

    Nicoll, Kathleen; Sallam, Emad S.

    2017-12-01

    Though southern Egypt is currently hyperarid, relict freshwater carbonate deposits called tufas near Kurkur (region centered at 23° 54‧ N, 32° 19‧ E) indicate that ambient rainwater-fed alkaline springs formerly sourced drainages in the Sinn El-Kaddab or Eocene scarp, and precipitated carbonate tufa deposits at waterfall cascades, pools, and streams. Petrographic analysis enables the reconstruction of a variety of vegetated microenvironments during Quaternary time. The Kurkur tufas are very porous rocks with an abundance of fossil plant casts and molds making up the petrofabrics at the macroscale. The tufas also preserve laminations of successive generations of calcified remains of microbes visible at the microscopic scale. Original carbonate framework architectures are massive carbonate structures to the decameter scale, with characteristic highly porous and permeable rock fabrics, including vegetation-rich phytoherms and stromatolite forms. The tufas are relatively pristine, preserving their original rock textures with minimal post-depositional alteration. Structural controls affecting the development of tufa deposits near Kurkur include fissure, cracks and fault planes that would have enhanced groundwater recharge and emergence of carbonate-saturated springs from perched aquifers above the Nubian Aquifer System during periods of greater effective rainfall in the past when the water table was significantly higher. The Kurkur tufas are relict archives from phases when groundwater discharge supported comparatively more vegetation than the modern day, and spring flows sustained baseflow in the Wadi Kurkur tributary of the Upper Nile. Episodes of tufa deposition along now-defunct tributaries therefore reflect phases of a more integrated Nile drainage system.

  17. The Effects of Calorie Restriction in Depression and Potential Mechanisms

    Science.gov (United States)

    Zhang, Yifan; Liu, Changhong; Zhao, Yinghao; Zhang, Xingyi; Li, Bingjin; Cui, Ranji

    2015-01-01

    Depression, also called major depressive disorder, is a neuropsychiatric disorder jeopardizing an increasing number of the population worldwide. To date, a large number of studies have devoted great attention to this problematic condition and raised several hypotheses of depression. Based on these theories, many antidepressant drugs were developed for the treatment of depression. Yet, the depressed patients are often refractory to the antidepressant therapies. Recently, increasing experimental evidences demonstrated the effects of calorie restriction in neuroendocrine system and in depression. Both basic and clinical investigations indicated that short-term calorie restriction might induce an antidepressant efficacy in depression, providing a novel avenue for treatment. Molecular basis underlying the antidepressant actions of calorie restriction might involve multiple physiological processes, primarily including orexin signaling activation, increased CREB phosphorylation and neurotrophic effects, release of endorphin and ketone production. However, the effects of chronic calorie restriction were quite controversial, in the cases that it often resulted in the long-term detrimental effects via inhibiting the function of 5-HT system and decreasing leptin levels. Here we review such dual effects of calorie restriction in depression and potential molecular basis behind these effects, especially focusing on antidepressant effects. PMID:26412073

  18. Landauer's blow-torch effect in systems with entropic potential.

    Science.gov (United States)

    Das, Moupriya; Ray, Deb Shankar

    2015-11-01

    We consider local heating of a part of a two-dimensional bilobal enclosure of a varying cross section confining a system of overdamped Brownian particles. Since varying cross section in higher dimension results in an entropic potential in lower dimension, local heating alters the relative stability of the entropic states. We show that this blow-torch effect modifies the entropic potential in a significant way so that the resultant effective entropic potential carries both the features of variation of width of the confinement and variation of temperature along the direction of transport. The reduced probability distribution along the direction of transport calculated by full numerical simulations in two dimensions agrees well with our analytical findings. The extent of population transfer in the steady state quantified in terms of the integrated probability of residence of the particles in either of the two lobes exhibits interesting variation with the mean position of the heated region. Our study reveals that heating around two particular zones of a given lobe maximizes population transfer to the other.

  19. Cognitive Effects of Air Pollution Exposures and Potential Mechanistic Underpinnings.

    Science.gov (United States)

    Allen, J L; Klocke, C; Morris-Schaffer, K; Conrad, K; Sobolewski, M; Cory-Slechta, D A

    2017-06-01

    This review sought to address the potential for air pollutants to impair cognition and mechanisms by which that might occur. Air pollution has been associated with deficits in cognitive functions across a wide range of epidemiological studies, both with developmental and adult exposures. Studies in animal models are significantly more limited in number, with somewhat inconsistent findings to date for measures of learning, but show more consistent impairments for short-term memory. Potential contributory mechanisms include oxidative stress/inflammation, altered levels of dopamine and/or glutamate, and changes in synaptic plasticity/structure. Epidemiological studies are consistent with adverse effects of air pollutants on cognition, but additional studies and better phenotypic characterization are needed for animal models, including more precise delineation of specific components of cognition that are affected, as well as definitions of critical exposure periods for such effects and the components of air pollution responsible. This would permit development of more circumscribed hypotheses as to potential behavioral and neurobiological mechanisms.

  20. Effects of prebiotics on the infective potential of Listeria monocytogenes

    DEFF Research Database (Denmark)

    Ebersbach, Tine

    % xylooligosaccharides (XOS), galactooligosaccharides (GOS), inulin, apple pectin or polydextrose for three weeks before oral challenge with L. monocytogenes. XOS and GOS significantly improved resistance of guinea pigs to L. monocytogenes, while inulin and apple pectin decreased the resistance. No significant effect...... on resistance to L. monocytogenes was seen after feeding with polydextrose. To further explore the mechanisms behind these in vivo observations, microbiota independent effects of four of the carbohydrates (XOS, GOS, inulin and polydextrose) on the adhesive and infective potential of L. monocytogenes....... monocytogenes to Caco-2 cells. No effect on adhesion was seen for either GOS, inulin or polydextrose. Adherence to the intestinal epithelium is considered a very important step in the infection cycle for most of the pathogenic bacteria. Without adherence the pathogenic bacteria are rapidly eliminated from...

  1. Under siege: Isolated tributaries are threatened by regionally impaired metacommunities

    International Nuclear Information System (INIS)

    Merriam, Eric R.; Petty, J. Todd

    2016-01-01

    Pristine streams are often targeted as conservation priorities because of their ability to preserve regional biodiversity. However, isolation within heavily degraded regions likely alters important metapopulation and metacommunity processes (e.g., rescue and mass effects), affecting the ability of in-tact communities to boost regional conditions. To test this hypothesis, we sampled invertebrate communities and physicochemical conditions from 168 streams within the mountaintop removal-valley fill mining region of West Virginia. We used redundancy analysis to first test for significant effects of local (observed physicochemical conditions) and neighborhood (streams within a 5 km buffer) degradation on assemblage structure across all taxa and stress tolerance (low, moderate, high) and dispersal (low, high) categories. We then used generalized linear and hurdle models to characterize changes in community metrics and individual taxa, respectively. Local condition consistently explained the majority of variation (partial R 2 up to 5 × those of neighborhood condition) in community structure and was the only factor affecting sensitive taxa. Neighborhood condition explained significant variation in moderately tolerant taxa with low dispersal capacity and highly tolerant taxa, regardless of dispersal. Decreased occurrence (Baetis) and abundance (Maccaffertium) of key taxa and corresponding metrics (%E, %EPT) suggest decreased dispersal and associated mass and rescue effects within degraded neighborhoods. Decreased neighborhood conditions also resulted in the proliferation of tolerant taxa (Chironomidae, Chimarra, Hemerodromia). Our results suggest communities within even the most pristine streams are at risk when isolated within heavily impacted regions. Consequently, protection of regional species' pools in heavily impacted regions will require more than simply conserving un-impacted streams. - Graphical abstract: In heavily degraded regions, even the most pristine

  2. Under siege: Isolated tributaries are threatened by regionally impaired metacommunities

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, Eric R., E-mail: emerriam@mix.wvu.edu; Petty, J. Todd

    2016-08-01

    Pristine streams are often targeted as conservation priorities because of their ability to preserve regional biodiversity. However, isolation within heavily degraded regions likely alters important metapopulation and metacommunity processes (e.g., rescue and mass effects), affecting the ability of in-tact communities to boost regional conditions. To test this hypothesis, we sampled invertebrate communities and physicochemical conditions from 168 streams within the mountaintop removal-valley fill mining region of West Virginia. We used redundancy analysis to first test for significant effects of local (observed physicochemical conditions) and neighborhood (streams within a 5 km buffer) degradation on assemblage structure across all taxa and stress tolerance (low, moderate, high) and dispersal (low, high) categories. We then used generalized linear and hurdle models to characterize changes in community metrics and individual taxa, respectively. Local condition consistently explained the majority of variation (partial R{sup 2} up to 5 × those of neighborhood condition) in community structure and was the only factor affecting sensitive taxa. Neighborhood condition explained significant variation in moderately tolerant taxa with low dispersal capacity and highly tolerant taxa, regardless of dispersal. Decreased occurrence (Baetis) and abundance (Maccaffertium) of key taxa and corresponding metrics (%E, %EPT) suggest decreased dispersal and associated mass and rescue effects within degraded neighborhoods. Decreased neighborhood conditions also resulted in the proliferation of tolerant taxa (Chironomidae, Chimarra, Hemerodromia). Our results suggest communities within even the most pristine streams are at risk when isolated within heavily impacted regions. Consequently, protection of regional species' pools in heavily impacted regions will require more than simply conserving un-impacted streams. - Graphical abstract: In heavily degraded regions, even the most

  3. Pharmacological effects and potential therapeutic targets of DT-13.

    Science.gov (United States)

    Khan, Ghulam Jilany; Rizwan, Mohsin; Abbas, Muhammad; Naveed, Muhammad; Boyang, Yu; Naeem, Muhammad Ahsan; Khan, Sara; Yuan, Shengtao; Baig, Mirza Muhammad Faran Ashraf; Sun, Li

    2018-01-01

    DT-13 is an isolated compound from Dwarf lillytruf tuber and currently among active research drugs by National Natural Science foundation of China for its several potential effects. The drug has been reported for its multiple pharmacological actions however no thorough review studies are available on it. Our present study is highlighting the pros and cons of DT-13 focusing on its potential pharmacological actions, therapeutic utilization and further exploration for novel targets. The drug possesses very low toxicity profile, quick onset and long duration of action with slow elimination that combinely makes it favorable for the clinical studies. In vivo and in vitro studies show that the drug regulates multiple cellular functions for its several pharmacological effects including, anti-adhesive effects via regulation of tissue factor and transforming growth factor; anti-migratory effects through indirect regulation of NM-IIA in the tumor microenvironment, Tissue factor, down-regulation of CCR5-CCL5 axis and MMP-2/9 inhibition; anti-metastatic effects via regulation of MMPs and tissue factor; pro-apoptotic effects by modulation of endocytosis of EGF receptor; anti-angiogenic effects via regulation of HIF-1α,ERK, Akt signalling and autophagy inducing characteristics by regulating PI3K/Akt/mTOR signalling pathway. In addition to anti-tumor activities, DT-13 has significant anti-inflammatory, cardioprotective, hepatoprotective and immunomodulating effects. Pharmaceutical dosage form and targeted drug delivery system for DT-13 has not been established yet. Moreover, DT-13, has not been studied for its action on brain, colorectal, hepatic, pancreatic, prostate and blood cancers. Similarly the effects of drug on carbohydrate and glucose metabolism is another niche yet to be explored. In some traditional therapies, crude drug from the plant is used against diabetic and neurological disorders that are not reported in scientific literature, however due to profound effects of

  4. Brain potentials associated with the outcome processing in framing effects.

    Science.gov (United States)

    Ma, Qingguo; Feng, Yandong; Xu, Qing; Bian, Jun; Tang, Huixian

    2012-10-24

    Framing effect is a cognitive bias referring to the phenomenon that people respond differently to different but objectively equivalent descriptions of the same problem. By measuring event-related potentials, the present study aimed to investigate the neural mechanisms underlying the framing effect, especially how the negative and positive frames influence the outcome processing in our brain. Participants were presented directly with outcomes framed either positively in terms of lives saved or negatively in terms of lives lost in large and small group conditions, and were asked to rate the favorableness of each of them. The behavioral results showed that the framing effect occurred in both group size conditions, with more favorable evaluations associated with positive framing. Compared with outcomes in positive framing condition, a significant feedback-related negativity (FRN) effect was elicited by outcomes in negative framing condition, even though the outcomes in different conditions were objectively equivalent. The results are explained in terms of the associative model of attribute framing effect which states that attribute framing effect occurs as a result of a valence-based associative processing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Structure of the effective potential for a spherical wormhole

    International Nuclear Information System (INIS)

    Montelongo Garcia, N.; Zannias, T.

    2008-01-01

    The structure of the effective potential V describing causal geodesics near the throat of an arbitrary spherical wormhole is analyzed. Einstein's equations relative to a set of regular coordinates covering a vicinity of the throat imply that any spherical wormhole can be constructed from solutions of an effective initial value problem with the throat serving as an initial value surface. The initial data involve matter variables, the area A(0) of the throat, and the gradient Λ(0) of the redshift factor on the throat. Whenever Λ(0)=0, the effective potential V has a critical point on the throat. Conditions upon the data are derived ensuring that the critical point is a local minimum (respectively maximum). For particular families of quasi-Schwarzschild wormholes, V exhibits a local minimum on the throat independently upon the energy E and angular momentum L 2 of the test particles and thus such wormholes admit stable circular timelike and null geodesics on the throat. For families of Chaplygin wormholes, we show that such geodesics are unstable. Based on a suitable power series representation of the metric, properties of V away from the throat are obtained that are useful for the analysis of accretion disks and radiation processes near the throat of any spherical wormhole.

  6. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus) elucidated by otolith microchemistry.

    Science.gov (United States)

    Fukushima, Michio; Jutagate, Tuantong; Grudpan, Chaiwut; Phomikong, Pisit; Nohara, Seiichi

    2014-01-01

    The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus), two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr) and barium (Ba) showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  7. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus elucidated by otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Michio Fukushima

    Full Text Available The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus, two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr and barium (Ba showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  8. On the one-loop effective potential in quantum gravity

    International Nuclear Information System (INIS)

    Yasuda, O.

    1984-01-01

    The one-loop effective potential is investigated in quantum gravity with or without cosmological constant in general D dimensions. It is shown that the partition function at the one-loop level depends only on the laplacian plus the scalar curvature with no terms of the form delta(0) ln g, i.e. Z (1-loop)=detsup(-1/2) (Δ 2 +2R/D)xdetsup(1/2) (Δsub(+)2R/D). An explicit calculation is carried out at the one-loop level to demonstrate gauge independence of the partition function in a class of general linear gauges. (orig.)

  9. Clyde tributaries : report of urban stream sediment and surface water geochemistry for Glasgow

    OpenAIRE

    Fordyce, F.M.; O Dochartaigh, B.E.O.; Lister, T.R.; Cooper, R.; Kim, A.; Harrison, I.; Vane, C.; Brown, S.E.

    2004-01-01

    This report presents the results of an urban drainage geochemical survey carried out jointly by the British Geological Survey (BGS) and Glasgow City Council (GCC) during June 2003. 118 stream sediment and 122 surface water samples were collected at a sample density of 1 per 1 km2 from all tributaries draining into the River Clyde within the GCC administrative area. The study was carried out as part of the BGS systematic Geochemical Surveys of Urban Environments (GSUE) programme. Stream sed...

  10. Albemarle Sound demonstration study of the national monitoring network for US coastal waters and their tributaries

    Science.gov (United States)

    Michelle Moorman; Sharon Fitzgerald; Keith Loftin; Elizabeth Fensin

    2016-01-01

    The U.S. Geological Survey’s (USGS) is implementing a demonstration project in the Albemarle Sound for the National Monitoring Network for U.S. coastal waters and their tributaries. The goal of the National Monitoring Network is to provide information about the health of our oceans and coastal ecosystems and inland influences on coastal waters for improved resource...

  11. Potentiating Effects of Lactuca sativa on Pentobarbital-Induced Sleep.

    Science.gov (United States)

    Ghorbani, Ahmad; Rakhshandeh, Hassan; Sadeghnia, Hamid Reza

    2013-01-01

    Traditionally, Lactuca sativa (lettuce) has been recommended for its hypnotic property. The present study was planned to investigate sleep-prolonging effect of this plant. The hydro-alcoholic extract (HAE) of lettuce and its water fraction (WF), ethyl acetate fraction (EAF), and n-butanol fraction (NBF) were administrated (IP) to mice 30 min before the pentobarbital injection. Moreover, both in-vivo and in-vitro toxicity of the extracts were determined. The quality of HAE and NBF was also evaluated using HPLC fingerprint. The HAE prolonged the pentobarbital-induced sleep duration at dose of 400 mg/Kg. The NBF was the only fraction which could increase the sleep duration and decrease sleep latency. The effects of NBF were comparable to those of induced by diazepam. The LD50-value for HAE was found to be 4.8 g/Kg. No neurotoxic effect was observed either by HAE or by its fractions in cultured PC12 neuron-like cells. The results suggest that lettuce potentiates pentobarbital hypnosis without major toxic effect. The main component(s) responsible for this effect is most likely to be non-polar agent(s) which found in NBF of this plant.

  12. Potential environmental effects of energy conservation measures in northwest industries

    Energy Technology Data Exchange (ETDEWEB)

    Baechler, M C; Gygi, K F; Hendrickson, P L

    1992-01-01

    The Bonneville Power Administration (Bonneville) has identified 101 plants in the Pacific Northwest that account for 80% of the region's industrial electricity consumption. These plants offer a precise target for a conservation program. PNL determined that most of these 101 plants were represented by 11 major industries. We then reviewed 36 major conservation technologies used in these 11 industrial settings to determine their potential environmental impacts. Energy efficiency technologies designed for industrial use may result in direct or indirect environmental impacts. Effects may result from the production of the conservation measure technology, changes in the working environment due to different energy and material requirements, or changes to waste streams. Industry type, work-place conditions, worker training, and environmental conditions inside and outside the plant are all key variables that may affect environmental outcomes. To address these issues this report has three objectives: Describe potential conservation measures that Bonneville may employ in industrial programs and discuss potential primary impacts. Characterize industrial systems and processes where the measure may be employed and describe general environmental issues associated with each industry type. Review environmental permitting, licensing, and other regulatory actions required for industries and summarize the type of information available from these sources for further analysis.

  13. Water Quality of a Reservoir and Its Major Tributary Located in East-Central Mexico

    Science.gov (United States)

    Castilla-Hernández, Patricia; Torres-Alvarado, María del Rocío; Herrera-San Luis, José Antonio; Cruz-López, Norma

    2014-01-01

    A reservoir with ecological and economic importance and its major tributary, localized in east-central Mexico, were studied. The aim of this work was to know the physicochemical water characteristics of both water bodies and to contrast these by their different uses, and also estimate overall water quality using a Water Quality Index (WQI). Water samples from the reservoir and the tributary were obtained in different climatic seasons. In the tributary, anoxic and hypoxic conditions and high levels of organic matter, orthophosphate, and ammonium showed that this is strongly impacted by wastewater discharges and that the water is not suitable for different uses; independently of the season, the WQI showed “poor” quality (34.4–47.2). In contrast, in the reservoir a better water quality was determined; the WQI in the sampling months ranged from 72.1–76.6 (“good” quality), and spatially, this was from 66.5–79.5 (“fair” and “good” quality). PMID:24919132

  14. Seasonal habitat use of brook trout and juvenile steelhead in a Lake Ontario tributary

    Science.gov (United States)

    Johnson, James H.; Abbett, Ross; Chalupnicki, Marc A.; Verdoliva, Francis

    2016-01-01

    Brook trout (Salvelinus fontinalis) are generally restricted to headwaters in New York tributaries of Lake Ontario. In only a few streams are brook trout abundant in lower stream reaches that are accessible to adult Pacific salmonids migrating from the lake. Consequently, because of the rarity of native brook trout populations in these lower stream reaches it is important to understand how they use stream habitat in sympatry with juvenile Pacific salmonids which are now naturalized in several Lake Ontario tributaries. In this study, we examined the seasonal (spring, summer, and fall) habitat use of brook trout and juvenile steelhead (Oncorhynchus mykiss) in Hart Brook, a tributary of eastern Lake Ontario. We found interspecific, intraspecific, and seasonal variation in habitat use. Subyearling steelhead were associated with faster water velocities than subyearling brook trout and, overall, had the least habitat similarity to the other salmonid groups examined. Overyearling brook trout and yearling steelhead exhibited the greatest degree of habitat selection and habitat selection by all four salmonid groups was greatest in summer. The availability of pool habitat for overyearling salmonids may pose the largest impediment to these species in Hart Brook.

  15. Bioavailability, metabolism and potential health protective effects of dietary flavonoids

    DEFF Research Database (Denmark)

    Bredsdorff, Lea

    Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... epidemiological studies but the evidence is inconclusive. One major obstacle for epidemiological studies investigating associations between flavonoid intake and risk of CHD is the estimation of flavonoid intake. There is a vast variety of flavonoids in commonly eaten food products but only limited knowledge...... of their content. In addition, variation in individual metabolic genotype and microflora may greatly affect the actual flavonoid exposure. The preventive effects of flavonoids on CHD are mainly ascribed to their anti-inflammatory and antioxidant activities. Several mechanisms of anti-inflammatory and antioxidant...

  16. One-loop effective potential in nonlocal supersymmetric theories

    Science.gov (United States)

    de Mello, E. R. Bezerra; Gama, F. S.; Nascimento, J. R.; Petrov, A. Yu.

    2017-01-01

    Within the superfield approach, we consider the nonlocal generalization of the Wess-Zumino model and calculate the one-loop low-energy contributions to the effective action. Four different nonlocal models are considered, among which only the first model does not reduce to the standard Wess-Zumino model when we take the parameter of nonlocality of the model, Λ , much greater than any energy scale; in addition, this model also depends on an extra parameter ξ . As to the other three models, the result looks like the renormalized effective potential for the usual Wess-Zumino model, where the normalization scale μ is replaced by the Λ . Moreover, the fourth model displays a divergence which can be eliminated through the appropriate wave function renormalization.

  17. The potential therapeutic effects of THC on Alzheimer's disease.

    Science.gov (United States)

    Cao, Chuanhai; Li, Yaqiong; Liu, Hui; Bai, Ge; Mayl, Jonathan; Lin, Xiaoyang; Sutherland, Kyle; Nabar, Neel; Cai, Jianfeng

    2014-01-01

    The purpose of this study was to investigate the potential therapeutic qualities of Δ9-tetrahydrocannabinol (THC) with respect to slowing or halting the hallmark characteristics of Alzheimer's disease. N2a-variant amyloid-β protein precursor (AβPP) cells were incubated with THC and assayed for amyloid-β (Aβ) levels at the 6-, 24-, and 48-hour time marks. THC was also tested for synergy with caffeine, in respect to the reduction of the Aβ level in N2a/AβPPswe cells. THC was also tested to determine if multiple treatments were beneficial. The MTT assay was performed to test the toxicity of THC. Thioflavin T assays and western blots were performed to test the direct anti-Aβ aggregation significance of THC. Lastly, THC was tested to determine its effects on glycogen synthase kinase-3β (GSK-3β) and related signaling pathways. From the results, we have discovered THC to be effective at lowering Aβ levels in N2a/AβPPswe cells at extremely low concentrations in a dose-dependent manner. However, no additive effect was found by combining caffeine and THC together. We did discover that THC directly interacts with Aβ peptide, thereby inhibiting aggregation. Furthermore, THC was effective at lowering both total GSK-3β levels and phosphorylated GSK-3β in a dose-dependent manner at low concentrations. At the treatment concentrations, no toxicity was observed and the CB1 receptor was not significantly upregulated. Additionally, low doses of THC can enhance mitochondria function and does not inhibit melatonin's enhancement of mitochondria function. These sets of data strongly suggest that THC could be a potential therapeutic treatment option for Alzheimer's disease through multiple functions and pathways.

  18. Effective potential study of the Diluted Antiferromagnet in a Field

    Science.gov (United States)

    Yllanes, David; Fernandez, L. A.; Martin-Mayor, V.

    2011-03-01

    We present a numerical study of the three-dimensional Diluted Antiferromagnet in a Field (DAFF), one of the experimental realizations of the Random Field Ising Model. We work in a constrained ensemble (tethered ensemble) where the Helmholtz effective potential is featured, rather than the free energy. Our method cures the problem of a strong violation of self-averaging, thus allowing us to compute the correlation length for systems sizes up to L = 32 . This quantity, when measured in units of the lattice size, is independent of the system size at the critical point, a strong indication of a second-order phase transition. This scale invariance allows us to apply finite-size scaling in the form of Nightingale's phenomenological renormalization. We obtain accurate estimates of the critical exponents. Since our method reconstructs the effective potential, we can also compute accurately the hyperscaling violation exponent. We perform as well an investigation of the geometrical properties of the instanton-like configurations, namely, the minimal cost configurations joining the two ordered phases. This study sheds light on previous claims of a first-order phase transition in this system.

  19. A risk assessment study of water quality, biota, and legacy sediment prior to small dam removal in a tributary to the Delaware River.

    Science.gov (United States)

    Rothenberger, Megan B; Hoyt, Virginia; Germanoski, Dru; Conlon, Maricate; Wilson, John; Hitchings, Joshua

    2017-07-01

    The proposed removal of three run-of-river dams (all ≤5-m height) in eastern Pennsylvania along lower Bushkill Creek, a tributary of the Delaware River, has provided a valuable opportunity for multidisciplinary research involving the collection of more than 5 years of pre-removal monitoring data, analysis of heavy metals in legacy sediment cores, and associated toxicity assays to determine the singular and interactive effects of lead, copper, and cadmium on survival and behavior of a common macroinvertebrate found in Bushkill Creek. Monitoring data were collected from sites approximately 35 m upstream and downstream of dams and reference sites located approximately 5 km upstream of all dams. Results indicate that oxygen levels, macroinvertebrate diversity, and proportion of sensitive taxa were significantly lower upstream and downstream of dams in comparison with upstream reference reaches. The strong correlation between water quality and macroinvertebrates in this system implies that removal of the lower three dams would lead to improvements in water quality, biotic integrity, and resilience in lower Bushkill Creek. Sediment analyses and toxicity assays suggest that dam removal and sediment mobilization may route contaminated sediments downstream at concentrations that may harm more sensitive biota. However, macroinvertebrate mortality and behavior were not significantly different from clean water controls for the large majority of toxicity assays. All together, these results suggest that dams 1-3 are good candidates for successful stream restoration but that the removals would best be planned in a way that mitigates potential impacts of contaminated legacy sediment.

  20. Characterization of air freshener emission: the potential health effects.

    Science.gov (United States)

    Kim, Sanghwa; Hong, Seong-Ho; Bong, Choon-Keun; Cho, Myung-Haing

    2015-01-01

    Air freshener could be one of the multiple sources that release volatile organic compounds (VOCs) into the indoor environment. The use of these products may be associated with an increase in the measured level of terpene, such as xylene and other volatile air freshener components, including aldehydes, and esters. Air freshener is usually used indoors, and thus some compounds emitted from air freshener may have potentially harmful health impacts, including sensory irritation, respiratory symptoms, and dysfunction of the lungs. The constituents of air fresheners can react with ozone to produce secondary pollutants such as formaldehyde, secondary organic aerosol (SOA), oxidative product, and ultrafine particles. These pollutants then adversely affect human health, in many ways such as damage to the central nervous system, alteration of hormone levels, etc. In particular, the ultrafine particles may induce severe adverse effects on diverse organs, including the pulmonary and cardiovascular systems. Although the indoor use of air freshener is increasing, deleterious effects do not manifest for many years, making it difficult to identify air freshener-associated symptoms. In addition, risk assessment recognizes the association between air fresheners and adverse health effects, but the distinct causal relationship remains unclear. In this review, the emitted components of air freshener, including benzene, phthalate, and limonene, were described. Moreover, we focused on the health effects of these chemicals and secondary pollutants formed by the reaction with ozone. In conclusion, scientific guidelines on emission and exposure as well as risk characterization of air freshener need to be established.

  1. LBA-ECO LC-02 Tributary Coordinates, Acre River, Tri-national River Basin: 2003-2004

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides coordinates for points at the mouth of tributaries of the Acre River in the Tri-national River Basin in South America. Three Global...

  2. LBA-ECO LC-02 Tributary Coordinates, Acre River, Tri-national River Basin: 2003-2004

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides coordinates for points at the mouth of tributaries of the Acre River in the Tri-national River Basin in South America. Three Global...

  3. Assessing summer and fall chinook salmon restoration in the Upper Clearwater River and principal tributaries. Annual report 1994

    International Nuclear Information System (INIS)

    Arnsberg, B.D.; Statler, D.P.

    1995-08-01

    This is the first annual report of a five year study to assess summer and fall chinook salmon restoration potential in the upper Clearwater River and principal tributaries, Salmon, Grande Ronde, and Imnaha Rivers. During 1994, the authors focused primarily on assessing water temperatures and spawning habitat in the upper Clearwater River and principal tributaries. Water temperature analysis indicated a colder temperature regime in the upper Clearwater River above the North Fork Clearwater River confluence during the winter as compared to the lower Clearwater. This was due to warm water releases from Dworshak Reservoir on the North Fork moderating temperatures in the lower Clearwater River. Thermal temperature unit analysis and available literature suggest a 75% survival threshold level may be anticipated for chinook salmon egg incubation if spawning would occur by November 1 in the upper Clearwater River. Warm water upwelling in historic summer and fall chinook spawning areas may result in increased incubation survivals and will be tested in the future. The authors observed a total of 37 fall chinook salmon redds in the Clearwater River subbasin. They observed 30 redds in the mainstem Clearwater below the North Fork Clearwater River confluence and seven redds in the North Fork Clearwater River. No redds were observed in the South Fork Clearwater, Middle Fork Clearwater, or Selway Rivers. They observed one fall chinook salmon redd in the Salmon River. They recovered 10 fall chinook salmon carcasses in the Clearwater River to obtain biological measurements and to document hatchery contribution to spawning. Unseasonably high and cold Dworshak Dam releases coinciding with early juvenile fall chinook salmon rearing in the lower Clearwater River may be influencing selective life history traits including growth, smolt development, outmigration timing, behavior, and could be directly affecting survival. During July 1994, discharges from Dworshak Dam increased from a

  4. Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California, USA

    International Nuclear Information System (INIS)

    Hui, Clifford A.; Rudnick, Deborah; Williams, Erin

    2005-01-01

    Chinese mitten crabs (Eriocheir sinensis), endemic to Asia, were first reported in the San Francisco Bay in 1992. They are now established in nearly all San Francisco Bay tributaries. These crabs accumulate more metals, such as mercury, than crustaceans living in the water column. Because their predators include fish, birds, mammals and humans, their mercury burdens have an exceptional potential to impact the ecosystem and public health. We sought to elucidate the potential threat of mitten crab mercury burdens in three adjacent streams in southern San Francisco Bay, one of which is known to be contaminated with mercury. Mitten crabs had hepatopancreas concentrations of total mercury and methylmercury that did not differ among streams. The maximum burden we measured was below the action level of 1 ppm recommended by the USEPA. Hepatopancreas concentrations of methylmercury declined with increasing crab size, suggesting a mechanism for mercury excretion and that predators might reduce mercury exposure if they select larger crabs. Because mercury may be heterogeneously distributed among tissues, estimation of the impacts of crab mercury burdens on the environment requires more data on the feeding preferences of predators. - Hepatopancreas concentrations of mercury decline with crab size, which may have important consequences for bio-magnification in food webs

  5. Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California, USA

    Science.gov (United States)

    Hui, C.A.; Rudnick, D.; Williams, E.

    2005-01-01

    Chinese mitten crabs (Eriocheir sinensis), endemic to Asia, were first reported in the San Francisco Bay in 1992. They are now established in nearly all San Francisco Bay tributaries. These crabs accumulate more metals, such as mercury, than crustaceans living in the water column. Because their predators include fish, birds, mammals and humans, their mercury burdens have an exceptional potential to impact the ecosystem and public health. We sought to elucidate the potential threat of mitten crab mercury burdens in three adjacent streams in southern San Francisco Bay, one of which is known to be contaminated with mercury. Mitten crabs had hepatopancreas concentrations of total mercury and methylmercury that did not differ among streams. The maximum burden we measured was below the action level of 1 ppm recommended by the USEPA. Hepatopancreas concentrations of methylmercury declined with increasing crab size, suggesting a mechanism for mercury excretion and that predators might reduce mercury exposure if they select larger crabs. Because mercury may be heterogeneously distributed among tissues, estimation of the impacts of crab mercury burdens on the environment requires more data on the feeding preferences of predators. Hepatopancreas concentrations of mercury decline with crab size, which may have important consequences for bio-magnification in food webs. ?? 2004 Elsevier Ltd. All rights reserved.

  6. Hydrologic, land cover, and seasonal patterns of waterborne pathogens in Great Lakes tributaries

    Science.gov (United States)

    Lenaker, Peter L.; Corsi, Steven; Borchardt, Mark A.; Spencer, Susan K.; Baldwin, Austin K.; Lutz, Michelle A.

    2017-01-01

    Great Lakes tributaries are known to deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal patterns of waterborne pathogens (i.e. protozoa (2), pathogenic bacteria (4) human viruses, (8) and bovine viruses (8)) eight rivers were monitored in the Great Lakes Basin over 29 months from February 2011 to June 2013. Sampling locations represented a wide variety of land cover classes from urban to agriculture to forest. A custom automated pathogen sampler was deployed at eight sampling locations which provided unattended, flow-weighted, large-volume (120–1630 L) sampling. Human and bovine viruses and pathogenic bacteria were detected by real-time qPCR in 16%, 14%, and 1.4% of 290 samples collected while protozoa were never detected. The most frequently detected pathogens were: bovine polyomavirus (11%), and human adenovirus C, D, F (9%). Human and bovine viruses were present in 16.9% and 14.8% of runoff-event samples (n = 189) resulting from precipitation and snowmelt, and 13.9% and 12.9% of low-flow samples (n = 101), respectively, indicating multiple delivery mechanisms could be influential. Data indicated human and bovine virus prevalence was different depending on land cover within the watershed. Occurrence, concentration, and flux of human viruses were greatest in samples from the three sampling locations with greater than 25% urban influence than those with less than 25% urban influence. Similarly, occurrence, concentration, and flux of bovine viruses were greatest in samples from the two sampling locations with greater than 50 cattle/km2 than those with less than 50 cattle/km2. In seasonal analysis, human and bovine viruses occurred more frequently in spring and winter seasons than during the fall and summer. Concentration, occurrence, and flux in the context of hydrologic condition, seasonality, and land use must be considered for each watershed individually to develop effective watershed management

  7. Potential biological and ecological effects of flickering artificial light.

    Directory of Open Access Journals (Sweden)

    Richard Inger

    Full Text Available Organisms have evolved under stable natural lighting regimes, employing cues from these to govern key ecological processes. However, the extent and density of artificial lighting within the environment has increased recently, causing widespread alteration of these regimes. Indeed, night-time electric lighting is known significantly to disrupt phenology, behaviour, and reproductive success, and thence community composition and ecosystem functioning. Until now, most attention has focussed on effects of the occurrence, timing, and spectral composition of artificial lighting. Little considered is that many types of lamp do not produce a constant stream of light but a series of pulses. This flickering light has been shown to have detrimental effects in humans and other species. Whether a species is likely to be affected will largely be determined by its visual temporal resolution, measured as the critical fusion frequency. That is the frequency at which a series of light pulses are perceived as a constant stream. Here we use the largest collation to date of critical fusion frequencies, across a broad range of taxa, to demonstrate that a significant proportion of species can detect such flicker in widely used lamps. Flickering artificial light thus has marked potential to produce ecological effects that have not previously been considered.

  8. Potential harmful effects of dietary supplements in sports medicine.

    Science.gov (United States)

    Deldicque, Louise; Francaux, Marc

    2016-11-01

    The purpose of this article is to collect the most recent data regarding the safety of well-known or emerging dietary supplements used by athletes. From January 2014 to April 2016, about 30 articles have been published in the field. New data show that 90% of sports supplements contain trace of estrogenic endocrine disruptors, with 25% of them having a higher estrogenic activity than acceptable. About 50% of the supplements are contaminated by melamine, a source of nonprotein nitrogen. Additional data accumulate toward the safety of nitrate ingestion. In the last 2 years, the safety of emerging supplements such as higenamine, potentially interesting to lose weight, creatine nitrate and guanidinoacetic acid has been evaluated but still needs further investigation. The consumption of over-the-counter supplements is very popular in athletes. Although most supplements may be considered as safe when taking at the recommended doses, athletes should be aware of the potential risks linked to the consumption of supplements. In addition to the risks linked to overdosage and cross-effects when combining different supplements at the same time, inadvertent or deliberate contamination with stimulants, estrogenic compounds, diuretics or anabolic agents may occur.

  9. Effect of electrical potential of microbubbles on ozone dissolution

    Science.gov (United States)

    Hasegawa, H.; Kataoka, H.; Asano, K.

    2009-02-01

    Microbubbles make ozone water generation effective due to the high dissolution rate of gas in contrast to a conventional generating method. Therefore, it is presumable that ozone water generation using microbubbles can be achieved by the low concentration ozone gas. In our previous study, a compact and low power microbubble generator was developed. The microbubbles are generated by the local shear stress in the flow through a pipe with slits. In the present study, in order to investigate the relationship between the electrical potential of the gas-water interface and the cleaning of cloth using ozone microbubbles, two models with different slit angles (θ=30 and 60 deg) were installed. High concentration ozone water is produced for θ = 60 deg in contrast to the θ=30 deg case. When a cloth is washed in the θ=60 deg case, the soiled cloth can be cleaned easily in comparison with the θ=30 deg case, because the zeta potential of microbubbles for θ=60 deg is larger than that for θ=30 deg.

  10. Effects of stimulus duration on gustatory evoked potentials

    DEFF Research Database (Denmark)

    Rotvel, Camilla Arndal; Møller, Stine; Kivisaar, Kätlin

    The objective of the present study was to investigate the effect of tastant stimulus duration on the brain response. The brain response was measured by electroencephalography (EEG) which measures neural processes with high temporal resolution and may therefore complement sensory panel assessments....... 19 normal-tasting subjects (10 females, mean age ± sd: 27 ± 3) were stimulated with aqueous 0.5g/L sucralose in between continuous periods of non-chlorinated tap water to avoid somatosensory onsets. The sucralose stimulus duration was either short (~0.6s) or long (~4s) and presented in random...... sequence with 60 repetitions. The stimuli were delivered to the center of the tongue apex innervated by chorda tympani nerve. Brain response was recorded with 128 electrodes and the gustatory event related potential (GEP) was estimated by coherent averaging of all artefact free epochs. Focusing on the FC5...

  11. Bioavailability, metabolism and potential health protective effects of dietary flavonoids

    DEFF Research Database (Denmark)

    Bredsdorff, Lea

    Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several......, NMR spectroscopy and differential pH spectrophotometry. Quantification was performed on six of the eight conjugates based on calibration curves with the identical conjugates. There was no difference in the profile of the excreted conjugates according to treatment. The results demonstrated the more...... change in dose. The urinary excretion of ten dietary flavonoids was analysed after enzymatic hydrolysis by LC-MS and associated to the risk of ACS in a nested case-control study with 393 case-noncase pairs. The 393 case-noncase pairs were identified in the Danish Diet, Cancer and Health cohort comprising...

  12. Thermal phase transition with full 2-loop effective potential

    Science.gov (United States)

    Laine, M.; Meyer, M.; Nardini, G.

    2017-07-01

    Theories with extended Higgs sectors constructed in view of cosmological ramifications (gravitational wave signal, baryogenesis, dark matter) are often faced with conflicting requirements for their couplings; in particular those influencing the strength of a phase transition may be large. Large couplings compromise perturbative studies, as well as the high-temperature expansion that is invoked in dimensionally reduced lattice investigations. With the example of the inert doublet extension of the Standard Model (IDM), we show how a resummed 2-loop effective potential can be computed without a high-T expansion, and use the result to scrutinize its accuracy. With the exception of Tc, which is sensitive to contributions from heavy modes, the high-T expansion is found to perform well. 2-loop corrections weaken the transition in IDM, but they are moderate, whereby a strong transition remains an option.

  13. Thermal phase transition with full 2-loop effective potential

    Directory of Open Access Journals (Sweden)

    M. Laine

    2017-07-01

    Full Text Available Theories with extended Higgs sectors constructed in view of cosmological ramifications (gravitational wave signal, baryogenesis, dark matter are often faced with conflicting requirements for their couplings; in particular those influencing the strength of a phase transition may be large. Large couplings compromise perturbative studies, as well as the high-temperature expansion that is invoked in dimensionally reduced lattice investigations. With the example of the inert doublet extension of the Standard Model (IDM, we show how a resummed 2-loop effective potential can be computed without a high-T expansion, and use the result to scrutinize its accuracy. With the exception of Tc, which is sensitive to contributions from heavy modes, the high-T expansion is found to perform well. 2-loop corrections weaken the transition in IDM, but they are moderate, whereby a strong transition remains an option.

  14. Bioavailability, metabolism and potential health protective effects of dietary flavonoids

    DEFF Research Database (Denmark)

    Bredsdorff, Lea

    Dietary flavonoids constitute an important group of potential health protective compounds from fruits, vegetables, and plant-based products such as tea and wine. The beneficial effects of a diet high in flavonoids on the risk of coronary heart disease (CHD) have been shown in several...... change in dose. The urinary excretion of ten dietary flavonoids was analysed after enzymatic hydrolysis by LC-MS and associated to the risk of ACS in a nested case-control study with 393 case-noncase pairs. The 393 case-noncase pairs were identified in the Danish Diet, Cancer and Health cohort comprising...... that the study was too limited in size to account for the variation associated with quantifying flavonoids in spot-urine samples. However, the non-monotonic, but statistically significant, association between higher kaempferol excretion and lower risk of ACS indicate that the lack of associations were not due...

  15. Microbiota and neurologic diseases: potential effects of probiotics.

    Science.gov (United States)

    Umbrello, Giulia; Esposito, Susanna

    2016-10-19

    The microbiota colonizing the gastrointestinal tract have been associated with both gastrointestinal and extra-gastrointestinal diseases. In recent years, considerable interest has been devoted to their role in the development of neurologic diseases, as many studies have described bidirectional communication between the central nervous system and the gut, the so-called "microbiota-gut-brain axis". Considering the ability of probiotics (i.e., live non-pathogenic microorganisms) to restore the normal microbial population and produce benefits for the host, their potential effects have been investigated in the context of neurologic diseases. The main aims of this review are to analyse the relationship between the gut microbiota and brain disorders and to evaluate the current evidence for the use of probiotics in the treatment and prevention of neurologic conditions. Overall, trials involving animal models and adults have reported encouraging results, suggesting that the administration of probiotic strains may exert some prophylactic and therapeutic effects in a wide range of neurologic conditions. Studies involving children have mainly focused on autism spectrum disorder and have shown that probiotics seem to improve neuro behavioural symptoms. However, the available data are incomplete and far from conclusive. The potential usefulness of probiotics in preventing or treating neurologic diseases is becoming a topic of great interest. However, deeper studies are needed to understand which formulation, dosage and timing might represent the optimal regimen for each specific neurologic disease and what populations can benefit. Moreover, future trials should also consider the tolerability and safety of probiotics in patients with neurologic diseases.

  16. Occurrence and variability of mining-related lead and zinc in the Spring River flood plain and tributary flood plains, Cherokee County, Kansas, 2009--11

    Science.gov (United States)

    Juracek, Kyle E.

    2013-01-01

    Historical mining activity in the Tri-State Mining District (TSMD), located in parts of southeast Kansas, southwest Missouri, and northeast Oklahoma, has resulted in a substantial ongoing input of cadmium, lead, and zinc to the environment. To provide some of the information needed to support remediation efforts in the Cherokee County, Kansas, superfund site, a 4-year study was begun in 2009 by the U.S. Geological Survey that was requested and funded by the U.S. Environmental Protection Agency. A combination of surficial-soil sampling and coring was used to investigate the occurrence and variability of mining-related lead and zinc in the flood plains of the Spring River and several tributaries within the superfund site. Lead- and zinc-contaminated flood plains are a concern, in part, because they represent a long-term source of contamination to the fluvial environment. Lead and zinc contamination was assessed with reference to probable-effect concentrations (PECs), which represent the concentrations above which adverse aquatic biological effects are likely to occur. The general PECs for lead and zinc were 128 and 459 milligrams per kilogram, respectively. The TSMD-specific PECs for lead and zinc were 150 and 2,083 milligrams per kilogram, respectively. Typically, surficial soils in the Spring River flood plain had lead and zinc concentrations that were less than the general PECs. Lead and zinc concentrations in the surficial-soil samples were variable with distance downstream and with distance from the Spring River channel, and the largest lead and zinc concentrations usually were located near the channel. Lead and zinc concentrations larger than the general or TSMD-specific PECs, or both, were infrequent at depth in the Spring River flood plain. When present, such contamination typically was confined to the upper 2 feet of the core and frequently was confined to the upper 6 inches. Tributaries with few or no lead- and zinc-mined areas in the basin—Brush Creek

  17. Compilation of watershed models for tributaries to the Great Lakes, United States, as of 2010, and identification of watersheds for future modeling for the Great Lakes Restoration Initiative

    Science.gov (United States)

    Coon, William F.; Murphy, Elizabeth A.; Soong, David T.; Sharpe, Jennifer B.

    2011-01-01

    developed by the National Soil Erosion Research Laboratory of the U.S. Department of Agriculture. During 2010, the USGS used the Precipitation-Runoff Modeling System (PRMS) to create a hydrologic model for the Lake Michigan Basin to assess the probable effects of climate change on future groundwater and surface-water resources. The Water Availability Tool for Environmental Resources (WATER) model and the Analysis of Flows In Networks of CHannels (AFINCH) program also were used to support USGS GLRI projects that required estimates of streamflows throughout the Great Lakes Basin. This information on existing watershed models, along with an assessment of geologic, soils, and land-use data across the Great Lakes Basin and the identification of problems that exist in selected tributary watersheds that could be addressed by a watershed model, was used to identify three watersheds in the Great Lakes Basin for future modeling by the USGS. These watersheds are the Kalamazoo River Basin in Michigan, the Tonawanda Creek Basin in New York, and the Bad River Basin in Wisconsin. These candidate watersheds have hydrogeologic, land-type, and soil characteristics that make them distinct from each other, but that are representative of other tributary watersheds within the Great Lakes Basin. These similarities in the characteristics among nearby watersheds will enhance the usefulness of a model by improving the likelihood that parameter values from a previously modeled watershed could reliably be used in the creation of a model of another watershed in the same region. The software program Hydrological Simulation Program–Fortran (HSPF) was selected to simulate the hydrologic, sedimentary, and water-quality processes in these selected watersheds. HSPF is a versatile, process-based, continuous-simulation model that has been used extensively by the scientific community, has the ongoing technical support of the U.S. Environmental Protection Agency and USGS, and provides a means to evaluate the

  18. Abuse potential and adverse cognitive effects of mitragynine (kratom).

    Science.gov (United States)

    Yusoff, Nurul H M; Suhaimi, Farah W; Vadivelu, Raja K; Hassan, Zurina; Rümler, Anne; Rotter, Andrea; Amato, Davide; Dringenberg, Hans C; Mansor, Sharif M; Navaratnam, Visweswaran; Müller, Christian P

    2016-01-01

    Mitragynine is the major psychoactive alkaloid of the plant kratom/ketum. Kratom is widely used in Southeast Asia as a recreational drug, and increasingly appears as a pure compound or a component of 'herbal high' preparations in the Western world. While mitragynine/kratom may have analgesic, muscle relaxant and anti-inflammatory effects, its addictive properties and effects on cognitive performance are unknown. We isolated mitragynine from the plant and performed a thorough investigation of its behavioural effects in rats and mice. Here we describe an addictive profile and cognitive impairments of acute and chronic mitragynine administration, which closely resembles that of morphine. Acute mitragynine has complex effects on locomotor activity. Repeated administration induces locomotor sensitization, anxiolysis and conditioned place preference, enhances expression of dopamine transporter- and dopamine receptor-regulating factor mRNA in the mesencephalon. While there was no increase in spontaneous locomotor activity during withdrawal, animals showed hypersensitivity towards small challenging doses for up to 14 days. Severe somatic withdrawal signs developed after 12 hours, and increased level of anxiety became evident after 24 hours of withdrawal. Acute mitragynine independently impaired passive avoidance learning, memory consolidation and retrieval, possibly mediated by a disruption of cortical oscillatory activity, including the suppression of low-frequency rhythms (delta and theta) in the electrocorticogram. Chronic mitragynine administration led to impaired passive avoidance and object recognition learning. Altogether, these findings provide evidence for an addiction potential with cognitive impairments for mitragynine, which suggest its classification as a harmful drug. © 2014 Society for the Study of Addiction.

  19. Potential economic effects of climate change on Finnish agriculture

    Directory of Open Access Journals (Sweden)

    L. KETTUNEN

    2008-12-01

    Full Text Available In the assessment of the economic effects of climate change, changes in returns and costs have to be taken into consideration. Changes in returns are mainly caused by changes in the yield level. Costs are determined by various factors. Harvesting conditions may improve as the temperatures are higher. However, an increasing need for disease and pest control results in higher costs. Various extensive studies have indicated that rising temperatures with the CO2 fertilizing effect increase the crop potential in Finland. From the economic point of view an increase in yield level is highly significant, because the increase in costs remains quite small. A 10% increase in the yield level raises the farm income by about 6%. Because agriculture is supported in many ways either directly or indirectly, the rise in income level may be offset by lowering the support. Consequently, farmers may not benefit from an increase in the yield level, but the benefit will go to the state economy. However, an increase in the yield level resulting from rising temperatures is advantageous to the national economy, regardless of whether the benefit goes to the farmers or to the state.;

  20. Potential of carbon nanotube field effect transistors for analogue circuits

    Directory of Open Access Journals (Sweden)

    Khizar Hayat

    2013-11-01

    Full Text Available This Letter presents a detailed comparison of carbon nanotube field effect transistors (CNFETs and metal oxide semiconductor field effect transistors (MOSFETs with special focus on carbon nanotube FET's potential for implementing analogue circuits in the mm-wave and sub-terahertz range. The latest CNFET lithographic dimensions place it at-par with complementary metal oxide semiconductor in terms of current handling capability, whereas the forecasted improvement in the lithography enables the CNFETs to handle more than twice the current of MOSFETs. The comparison of RF parameters shows superior performance of CNFETs with a g(m, f(T and f(max of 2.7, 2.6 and 4.5 times higher, respectively. MOSFET- and CNFET-based inverter, three-stage ring oscillator and LC oscillator have been designed and compared as well. The CNFET-based inverters are found to be ten times faster, the ring oscillator demonstrates three times higher oscillation frequency and CNFET-based LC oscillator also shows improved performance than its MOSFET counterpart.

  1. The potential effect of taurine as a radioprotective agent

    International Nuclear Information System (INIS)

    Sharoud, M.N.M.

    2010-01-01

    People can be exposed to irradiation either external or internal. The potential effects of radiation on health depend in part on the radiation dose delivered and the rate of delivery causing oxidation and free radical formation. The main purpose of the present study was to asses the effect of taurine administration in modulating some biochemical and hematological parameters in female rats exposed to 6 gray γ-irradiation. The data showed in this study that the ionizing γradiation (6 Gy) induced a significant (p<0.05) increment in the levels of serum lipid profile (cholesterol, triglycerides, HDL and LDL) and elevation of cardiac enzyme activities (LDH, CK and AST) and elevation in the activities of serum AST , ALT and ALP. on the other hand , the ionizing radiation induced a significant (p < 0.05) decline in the concentrations of serum total protein and albumin . In case of exposing female rat to gamma ray, the level of MDA was significantly elevated compared to their corresponding normal control group. Whereas, the drastic decrease were observed in hematological parameters (Hb, RBCs, WBCs and Hct). A significant correction was occurred in all previous parameters after the irradiated rats were intraperitoneally (i.p) injected with taurine (500 mg/100 g body weigh / day for one month). Leading to the conclusion that taurine is considered as antioxidant and a radio-protector agent.

  2. Potential of carbon nanotube field effect transistors for analogue circuits

    KAUST Repository

    Hayat, Khizar

    2013-05-11

    This Letter presents a detailed comparison of carbon nanotube field effect transistors (CNFETs) and metal oxide semiconductor field effect transistors (MOSFETs) with special focus on carbon nanotube FET\\'s potential for implementing analogue circuits in the mm-wave and sub-terahertz range. The latest CNFET lithographic dimensions place it at-par with complementary metal oxide semiconductor in terms of current handling capability, whereas the forecasted improvement in the lithography enables the CNFETs to handle more than twice the current of MOSFETs. The comparison of RF parameters shows superior performance of CNFETs with a g m , f T and f max of 2.7, 2.6 and 4.5 times higher, respectively. MOSFET- and CNFET-based inverter, three-stage ring oscillator and LC oscillator have been designed and compared as well. The CNFET-based inverters are found to be ten times faster, the ring oscillator demonstrates three times higher oscillation frequency and CNFET-based LC oscillator also shows improved performance than its MOSFET counterpart.

  3. Brain potentials associated with the shape Stroop effect.

    Science.gov (United States)

    Xiao, Xiao; Xie, Peng; Zhang, Qinglin

    2016-03-23

    Event-related potentials (ERPs) were recorded to explore, for the first time, the electrophysiological correlates of the shape Stroop effect. Fifteen healthy individuals were presented with a frame and a name of an object with a typical shape in life and asked to categorize the object's typical shape in life as a 'circle', a 'square,' or a 'triangle' by pressing the relevant button as quickly as possible. Accurate categorization of the name of an object was faster when it was presented with a congruent shape frame (e.g. name of a tyre/circle frame) than with an incongruent one (e.g. name of a tyre/square frame). Scalp ERPs analysis showed that the incongruent condition elicited a more negative component N430 and a more late positive component LPC than the congruent condition. N430 is a critical sign of conflict detection in the early stage, whereas late positive component reflects the response conflict in the late stage. The results provided evidence for the dissociation between conflict detection and conflict resolution in the shape Stroop effect.

  4. Cosmological phases of the string thermal effective potential

    Energy Technology Data Exchange (ETDEWEB)

    Bourliot, F., E-mail: Francois.Bourliot@cpht.polytechnique.f [Centre de Physique Theorique, Ecole Polytechnique, F-91128 Palaiseau cedex (France); Estes, J., E-mail: John.Estes@cpth.polytechnique.f [Centre de Physique Theorique, Ecole Polytechnique, F-91128 Palaiseau cedex (France); Kounnas, C., E-mail: Costas.Kounnas@lpt.ens.f [Laboratoire de Physique Theorique, Ecole Normale Superieure, 24 rue Lhomond, F-75231 Paris cedex 05 (France); Partouche, H., E-mail: Herve.Partouche@cpht.polytechnique.f [Centre de Physique Theorique, Ecole Polytechnique, F-91128 Palaiseau cedex (France)

    2010-05-01

    In a superstring framework, the free energy density F can be determined unambiguously at the full string level once supersymmetry is spontaneously broken via geometrical fluxes. We show explicitly that only the moduli associated to the supersymmetry breaking may give relevant contributions. All other spectator moduli mu{sub I} give exponentially suppressed contributions for relatively small (as compared to the string scale) temperature T and supersymmetry breaking scale M. More concisely, for mu{sub I}>T and M, F takes the form F(T,M;mu{sub I})=F(T,M)+O[exp(-(mu{sub I})/T ),exp(-(mu{sub I})/M )]. We study the cosmological regime where T and M are below the Hagedorn temperature scale T{sub H}. In this regime, F remains finite for any values of the spectator moduli mu{sub I}. We investigate extensively the case of one spectator modulus mu{sub d} corresponding to R{sub d}, the radius-modulus field of an internal compactified dimension. We show that its thermal effective potential V(T,M;mu)=F(T,M;mu) admits five phases, each of which can be described by a distinct but different effective field theory. For late cosmological times, the Universe is attracted to a 'Radiation-like evolution' with M(t)propor toT(t)propor to1/a(t)propor tot{sup -2/d}. The spectator modulus mu(t) is stabilized either to the stringy enhanced symmetry point where R{sub d}=1, or fixed at an arbitrary constant mu{sub 0}>T,M. For arbitrary boundary conditions at some initial time, t{sub E}, mu(t) may pass through more than one effective field theory phase before its final attraction.

  5. An effective pair potential for liquid semiconductor, Se: Structure and ...

    Indian Academy of Sciences (India)

    experimental structure factor data using an accurate liquid state theory and this shows important basic features. A model potential incorporating the basic features of the struc- ture factor extracted potential is suggested. This model potential is then used to describe through low-order perturbation theory, the structure and ...

  6. First direct confirmation of grass carp spawning in a Great Lakes tributary

    Science.gov (United States)

    Embke, Holly S.; Kocovsky, Patrick M.; Richter, Catherine A.; Pritt, Jeremy J.; Christine M. Mayer,; Qian, Song

    2016-01-01

    Grass carp (Ctenopharyngodon idella), an invasive species of Asian carp, has been stocked for many decades in the United States for vegetation control. Adult individuals have been found in all of the Great Lakes except Lake Superior, but no self-sustaining populations have yet been identified in Great Lakes tributaries. In 2012, a commercial fisherman caught four juvenile diploid grass carp in the Sandusky River, a major tributary to Lake Erie. Otolith microchemistry and the capture location of these fish permitted the conclusion that they were most likely produced in the Sandusky River. Due to this finding, we sampled ichthyoplankton using paired bongo net tows and larval light traps during June–August of 2014 and 2015 to determine if grass carp are spawning in the Sandusky River. From the samples collected in 2015, we identified and staged eight eggs that were morphologically consistent with grass carp. Five eggs were confirmed as grass carp using quantitative Polymerase Chain Reaction for a grass carp-specific marker, while the remaining three were retained for future analysis. Our finding confirms that grass carp are naturally spawning in this Great Lakes tributary. All eggs were collected during high-flow events, either on the day of peak flow or 1–2 days following peak flow, supporting an earlier suggestion that high flow conditions favor grass carp spawning. The next principal goal is to identify the spawning and hatch location(s) for the Sandusky River. Predicting locations and conditions where grass carp spawning is most probable may aid targeted management efforts.

  7. Planting depth effects and water potential effects on oak seedling emergence and acorn germination

    Science.gov (United States)

    Wayne A. Smiles; Jeffrey O. Dawson

    1995-01-01

    The effects of four planting depths (0, 3, 7, 11 cm) and acorn size on the percentage seedling emergence of red, pin, and black oak were determined. In a complimentary study, the effects of five water potential treatments (0, -.2, -.4, -.6, -1.0 MPa) on the percentage germination of red, pin, and black oak acorns were measured.

  8. Potential climate engineering effectiveness and side effects during a high carbon dioxide-emission scenario.

    Science.gov (United States)

    Keller, David P; Feng, Ellias Y; Oschlies, Andreas

    2014-02-25

    The realization that mitigation efforts to reduce carbon dioxide emissions have, until now, been relatively ineffective has led to an increasing interest in climate engineering as a possible means of preventing the potentially catastrophic consequences of climate change. While many studies have addressed the potential effectiveness of individual methods there have been few attempts to compare them. Here we use an Earth system model to compare the effectiveness and side effects of afforestation, artificial ocean upwelling, ocean iron fertilization, ocean alkalinization and solar radiation management during a high carbon dioxide-emission scenario. We find that even when applied continuously and at scales as large as currently deemed possible, all methods are, individually, either relatively ineffective with limited (effects and cannot be stopped without causing rapid climate change. Our simulations suggest that the potential for these types of climate engineering to make up for failed mitigation may be very limited.

  9. Reproductive health of yellow perch, Perca flavescens, in Chesapeake Bay Tributaries

    Science.gov (United States)

    Blazer, Vicki; Pinkney, A.E.; Uphoff, James H.

    2013-01-01

    Yellow perch live in creeks, rivers, ponds, lakes, and estuaries across the central and eastern United States and Canada. In Chesapeake Bay, they tolerate salinities up to one-third that of seawater. The adults reside in the brackish waters of the bay’s tributaries and migrate upstream to spawn. Yellow perch are eagerly sought by recreational fishermen for their excellent taste and, because their late winter spawning runs are the earliest of the year, they are regarded as a harbinger of spring. Yellow perch also support a small but valuable, tightly regulated commercial fishery in the part of Chesapeake Bay that lies in Maryland.

  10. FRESHWATER SHRIMPS OF THE COLOMBIAN TRIBUTARIES OF THE AMAZON AND ORINOCO RIVERS (PALAEMONIDAE, EURYRHYNCHIDAE, SERGESTIDAE

    Directory of Open Access Journals (Sweden)

    Valencia Diego

    2010-06-01

    Full Text Available A review of freshwater shrimps belonging to the genera Palaemonetes,Pseudopalaemon, Euryrhynchus and Acetes of the Colombian tributaries of theAmazon and Orinoco Rivers is presented. The species found in this work arerecorded for the fi rst time for Colombia: Palaemonetes ivonicus Holthuis, 1950,Palaemonetes mercedae Pereira, 1986, Pseudopalaemon amazonensis Ramos-Porto,1979, Pseudopalemon chryseus Kensley & Walker, 1982, Euryrhynchus amazoniensisTiefenbacher, 1978 and Acetes paraguayensis Hansen, 1919. Diagnoses, illustrations,distributional data and a key to the families, genera and species are presented.

  11. Potential environmental effects of fusion reactor power plants

    International Nuclear Information System (INIS)

    Young, J.R.; Gore, B.F.; Coffman, F.E.

    1976-01-01

    Construction and operation of fusion power plants is expected to reduce the total environmental effects of 21st century power generation. Fusion power plant impacts due to noise, odors, vibrations, and sanitary wastes are expected to be insignificant. impacts due to land use, chemical releases, and aesthetics are expected to be reduced. Impacts due to heat releases, local socio-economic changes, and non-radioactive liquid and solid disposal are expected to be comparable to those for the alternative fission or coal-fired power systems. Radiation doses to the public due to radioactive wastes are expected to be comparable to, or less than, the trivial low doses due to fission power systems. Research and development will be required, however, to assure adequate containment of tritium, the primary radioisotope of concern. Prevention of accidental tritium releases is within the capability of current engineering practice. Current technology is capable of handling the solid radioactive waste which may be produced, with insignificant environmental impact. Major research efforts are necessary to determine if subtle long-term effects of magnetic fields exist and should be of concern. In view of the large quantities of construction materials required for fusion. Material availability may dictate 21st century power plant design and construction. The accident potential of fusion power plants should be lower than for fission systems. Accidental criticalities and plasma runaways are not considered to be possible. Loss of coolant accidents are not expected to result in damage to the containment. No fission products or actinides are present to be released in an accident, and most activation products are immobilized in structures. The biological hazard of tritium is orders of magnitude smaller than for fission products and actinides. Safeguards against diversion of fissile materials are not expected to be necessary

  12. Potential energy surface for ? dissociation including spin-orbit effects

    Science.gov (United States)

    Siebert, Matthew R.; Aquino, Adelia J. A.; de Jong, Wibe A.; Granucci, Giovanni; Hase, William L.

    2012-10-01

    Previous experiments [J. Phys. Chem. A 116, 2833 (2012)] have studied the dissociation of 1,2-diiodoethane radical cation ( ? ) and found a one-dimensional distribution of translational energy, an odd finding considering most product relative translational energy distributions are two-dimensional. The goal of this study is to obtain an accurate understanding of the potential energy surface (PES) topology for the unimolecular decomposition reaction ? → C2H4I+ + I•. This is done through comparison of many single-reference electronic structure methods, coupled-cluster single-point (energy) calculations, and multi-reference energy calculations used to quantify spin-orbit (SO) coupling effects. We find that the structure of the ? reactant has a substantial effect on the role of the SO coupling on the reaction energy. Both the BHandH and MP2 theories with an ECP/6-31++G** basis set, and without SO coupling corrections, provide accurate models for the reaction energetics. MP2 theory gives an unsymmetric structure with different C-I bond lengths, resulting in a SO energy for ? similar to that for the product I-atom and a negligible SO correction to the reaction energy. In contrast, DFT gives a symmetric structure for ? , similar to that of the neutral C2H4I2 parent, resulting in a substantial SO correction and increasing the reaction energy by 6.0-6.5 kcalmol-1. Also, we find that, for this system, coupled-cluster single-point energy calculations are inaccurate, since a small change in geometry can lead to a large change in energy.

  13. Interactions among endophytic bacteria and fungi: effects and potentials.

    Science.gov (United States)

    Bandara, W M M S; Seneviratne, Gamini; Kulasooriya, S A

    2006-12-01

    Plants benefit extensively by harbouring endophytic microbes. They promote plant growth and confer enhanced resistance to various pathogens. However, the way the interactions among endophytes influence the plant productivity has not been explained. Present study experimentally showed that endophytes isolated from rice (Oryza sativa) used as the test plant produced two types of interactions; biofilms (bacteria attached to mycelia) and mixed cultures with no such attachments. Acidity, as measured by pH in cultures with biofilms was higher than that of fungi alone, bacteria alone or the mixed cultures. Production of indoleacetic acid like substances (IAAS) of biofilms was higher than that of mixed cultures, fungi or bacteria. Bacteria and fungi produced higher quantities of IAAS than mixed cultures. In mixed cultures, the potential of IAAS production of resident microbes was reduced considerably. There was a negative relationship between IAAS and pH of the biofilms, indicating that IAAS was the main contributor to the acidity. However, such a relationship was not observed in mixed cultures. Microbial acid production is important for suppressing plant pathogens. Thus the biofilm formation in endophytic environment seems to be very important for healthy and improved plant growth. However, it is unlikely that an interaction among endophytes takes place naturally in the endophytic environment, due to physical barriers of plant tissues. Further, critical cell density dependant quorum sensing that leads to biofilm formation may not occur in the endophytic environment as there is a limited space. As such in vitro production and application of beneficial biofilmed inocula of endophytes are important for improved plant production in any agro-ecosystem. The conventional practice of plant inoculation with monocultures or mixed cultures of effective microbes may not give the highest microbial effect, which may only be achieved by biofilm formation.

  14. Identifying nitrate sources and transformations in surface water by combining dual isotopes of nitrate and stable isotope mixing model in a watershed with different land uses and multi-tributaries

    Science.gov (United States)

    Wang, Meng; Lu, Baohong

    2017-04-01

    Nitrate is essential for the growth and survival of plants, animals and humans. However, excess nitrate in drinking water is regarded as a health hazard as it is linked to infant methemoglobinemia and esophageal cancer. Revealing nitrate characteristics and identifying its sources are fundamental for making effective water management strategies, but nitrate sources in multi-tributaries and mixed land covered watersheds remain unclear. It is difficult to determine the predominant NO3- sources using conventional water quality monitoring techniques. In our study, based on 20 surface water sampling sites for more than two years' monitoring from April 2012 to December 2014, water chemical and dual isotopic approaches (δ15N-NO3- and δ18O-NO3-) were integrated for the first time to evaluate nitrate characteristics and sources in the Huashan watershed, Jianghuai hilly region, East China. The results demonstrated that nitrate content in surface water was relatively low in the downstream (qualitatively analyze nitrate sources and transformations as well as quantitatively estimate the contributions of potential nitrate sources in surface water. With the assessment of nitrate sources and characteristics, effective management strategies can be implemented to reduce N export and improve water quality in this region.

  15. Potential Effects of Pomegranate Polyphenols in Cancer Prevention and Therapy

    Directory of Open Access Journals (Sweden)

    Eleonora Turrini

    2015-01-01

    Full Text Available Cancer is the second leading cause of death and is becoming the leading one in old age. Vegetable and fruit consumption is inversely associated with cancer incidence and mortality. Currently, interest in a number of fruits high in polyphenols has been raised due to their reported chemopreventive and/or chemotherapeutic potential. Pomegranate has been shown to exert anticancer activity, which is generally attributed to its high content of polyphenols. This review provides a comprehensive analysis of known targets and mechanisms along with a critical evaluation of pomegranate polyphenols as future anticancer agents. Pomegranate evokes antiproliferative, anti-invasive, and antimetastatic effects, induces apoptosis through the modulation of Bcl-2 proteins, upregulates p21 and p27, and downregulates cyclin-cdk network. Furthermore, pomegranate blocks the activation of inflammatory pathways including, but not limited to, the NF-κB pathway. The strongest evidence for its anticancer activity comes from studies on prostate cancer. Accordingly, some exploratory clinical studies investigating pomegranate found a trend of efficacy in increasing prostate-specific antigen doubling time in patients with prostate cancer. However, the genotoxicity reported for pomegranate raised certain concerns over its safety and an accurate assessment of the risk/benefit should be performed before suggesting the use of pomegranate or its polyphenols for cancer-related therapeutic purposes.

  16. Effects of discontinuities of the derivatives of the inflaton potential

    Energy Technology Data Exchange (ETDEWEB)

    Cadavid, Alexander Gallego [Instituto de Fisica, Universidad de Antioquia, A.A.1226, Medellin (Colombia); Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto (Japan); Romano, Antonio Enea, E-mail: aer@physics.uoc.gr [Instituto de Fisica, Universidad de Antioquia, A.A.1226, Medellin (Colombia); Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto (Japan); Department of Physics, University of Crete, 71003, Heraklion (Greece)

    2015-12-12

    We study the effects of a class of features of the inflaton potential, corresponding to discontinuities in its derivatives. We perform fully numerical calculations and derive analytical approximations for the curvature perturbations spectrum and the bispectrum which are in good agreement with the numerical results. The spectrum of primordial perturbations has oscillations around the scale k{sub 0} which leaves the horizon at the time τ{sub 0} when the feature occurs, with the amplitude and phase of the oscillations determined by the size and the order of the discontinuity. The large scale bispectrum in the squeezed and equilateral limits have a very similar form and are linearly suppressed. Both in the squeezed and the equilateral small scale limit the bispectrum has an oscillatory behavior whose phase depends on the parameters determining the discontinuity, and whose amplitude is inversely proportional to the scale. Given the generality of this class of features they could be used to model or classify phenomenologically different types of non-Gaussian features encountered in observational data such as the cosmic microwave background radiation or large scale structure.

  17. Effects of discontinuities of the derivatives of the inflaton potential

    Energy Technology Data Exchange (ETDEWEB)

    Gallego Cadavid, Alexander [Universidad de Antioquia, Instituto de Fisica, Medellin (Colombia); Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Enea Romano, Antonio [Universidad de Antioquia, Instituto de Fisica, Medellin (Colombia); Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); University of Crete, Department of Physics, Heraklion (Greece)

    2015-12-15

    We study the effects of a class of features of the inflaton potential, corresponding to discontinuities in its derivatives. We perform fully numerical calculations and derive analytical approximations for the curvature perturbations spectrum and the bispectrum which are in good agreement with the numerical results. The spectrum of primordial perturbations has oscillations around the scale k{sub 0} which leaves the horizon at the time τ{sub 0} when the feature occurs, with the amplitude and phase of the oscillations determined by the size and the order of the discontinuity. The large scale bispectrum in the squeezed and equilateral limits have a very similar form and are linearly suppressed. Both in the squeezed and the equilateral small scale limit the bispectrum has an oscillatory behavior whose phase depends on the parameters determining the discontinuity, and whose amplitude is inversely proportional to the scale. Given the generality of this class of features they could be used to model or classify phenomenologically different types of non-Gaussian features encountered in observational data such as the cosmic microwave background radiation or large scale structure. (orig.)

  18. Potential Effects of Pomegranate Polyphenols in Cancer Prevention and Therapy.

    Science.gov (United States)

    Turrini, Eleonora; Ferruzzi, Lorenzo; Fimognari, Carmela

    2015-01-01

    Cancer is the second leading cause of death and is becoming the leading one in old age. Vegetable and fruit consumption is inversely associated with cancer incidence and mortality. Currently, interest in a number of fruits high in polyphenols has been raised due to their reported chemopreventive and/or chemotherapeutic potential. Pomegranate has been shown to exert anticancer activity, which is generally attributed to its high content of polyphenols. This review provides a comprehensive analysis of known targets and mechanisms along with a critical evaluation of pomegranate polyphenols as future anticancer agents. Pomegranate evokes antiproliferative, anti-invasive, and antimetastatic effects, induces apoptosis through the modulation of Bcl-2 proteins, upregulates p21 and p27, and downregulates cyclin-cdk network. Furthermore, pomegranate blocks the activation of inflammatory pathways including, but not limited to, the NF-κB pathway. The strongest evidence for its anticancer activity comes from studies on prostate cancer. Accordingly, some exploratory clinical studies investigating pomegranate found a trend of efficacy in increasing prostate-specific antigen doubling time in patients with prostate cancer. However, the genotoxicity reported for pomegranate raised certain concerns over its safety and an accurate assessment of the risk/benefit should be performed before suggesting the use of pomegranate or its polyphenols for cancer-related therapeutic purposes.

  19. Potential Effects of Horizontal Gene Exchange in the Human Gut

    Directory of Open Access Journals (Sweden)

    Aaron Lerner

    2017-11-01

    Full Text Available Many essential functions of the human body are dependent on the symbiotic microbiota, which is present at especially high numbers and diversity in the gut. This intricate host–microbe relationship is a result of the long-term coevolution between the two. While the inheritance of mutational changes in the host evolution is almost exclusively vertical, the main mechanism of bacterial evolution is horizontal gene exchange. The gut conditions, with stable temperature, continuous food supply, constant physicochemical conditions, extremely high concentration of microbial cells and phages, and plenty of opportunities for conjugation on the surfaces of food particles and host tissues, represent one of the most favorable ecological niches for horizontal gene exchange. Thus, the gut microbial system genetically is very dynamic and capable of rapid response, at the genetic level, to selection, for example, by antibiotics. There are many other factors to which the microbiota may dynamically respond including lifestyle, therapy, diet, refined food, food additives, consumption of pre- and probiotics, and many others. The impact of the changing selective pressures on gut microbiota, however, is poorly understood. Presumably, the gut microbiome responds to these changes by genetic restructuring of gut populations, driven mainly via horizontal gene exchange. Thus, our main goal is to reveal the role played by horizontal gene exchange in the changing landscape of the gastrointestinal microbiome and potential effect of these changes on human health in general and autoimmune diseases in particular.

  20. Potential estrogenic effects of phosphorus-containing flame retardants.

    Science.gov (United States)

    Zhang, Quan; Lu, Meiya; Dong, Xiaowu; Wang, Cui; Zhang, Chunlong; Liu, Weiping; Zhao, Meirong

    2014-06-17

    As the substitute of polybrominated diphenyl ethers (PBDEs), further assessments about the potential ecological safety and health risks of phosphorus-containing flame retardants (PFRs) are required because the worldwide demand for PFRs has been increasing every year. In this study, we examined the agonistic/antagonistic activity of a group of PFRs by three in vitro models (luciferase reporter gene assay, yeast two-hybrid assay, and E-screen assay). Molecule docking was used to further explain the interactions between ERα and PFRs. Data from luciferase reporter gene analysis showed three members of the nine tested PFRs significantly induced estrogenic effects, with the order of TPP > TCP > TDCPP, while TCEP and TEHP have remarkable antiestrogenic properties with calculated REC20 and RIC20 values of 10(-6) M or lower. Results from the luciferase reporter gene method are generally consistent with results obtained from the yeast two-hybrid assay and E-screen, except for the positive estrogenic activity of TBP in E-screen testing. Docking results showed that binding between ligands and ERα was stabilized by hydrophobic interactions. As a proposed alternative for brominated flame retardant, PFRs may have anti/estrogenic activity via ERα at the low dose typical of residue in environmental matrix or animals. PFRs with a short chain, halogen, and benzene ring in the substituent group tend to be estrogenic. Our research suggests that comprehensive evaluations, including health and ecological assessments, are required in determining whether PFRs are preferable as an emerging industrial substitute.

  1. [Chemical contamination of the child: bioacumulation and potential effects].

    Science.gov (United States)

    del Río Paredes, Sara

    2005-01-01

    In early 2003, Greenpeace exposed the presence of persistent, bioaccumulative chemical pollutants in samples of house dust taken from homes across europe. Greenpeace further researches revealed that these same chemicals can be found in many daily consumer products. This report completes the loop by illustrating two disturbing developments. Firstly, that many of the same chemicals used routinely in consumer products and present in house dust, are also present in the human body, including in prenatal and newborn children. Secondly, that these chemicals are likely to be having a detrimental effect on the health of children and the human population at large. Dorey draws together the available evidence that illustrates how and why prenatal and newly born children are particularly at risk from chemical pollutants. The evidence presented here, from academics, governments and international institutions is not easily dismissed, contributing as it does to a growing bank of international research that reinforces the conclusion of this report--that current chemical legislation is failing to protect children from a harmful chemical assault that begins from a child's conception. The study focuses on seven key chemicals: alkylphenols, bisphenol A, brominated flame retardants, organotins, phthalates, chlorinated paraffins and artificial musks, and demonstrates: the presence of these substances in children, the ways in which children are particularly exposed, how this increased exposure increases the potential for detrimental health impacts, the different illnesses and diseases that are now being linked to this chemical exposure and the specific health impacts of the key chemicals listed above.

  2. Potential Therapeutic Effects of Meditation for Treating Affective Dysregulation

    Directory of Open Access Journals (Sweden)

    Natalie T. Y. Leung

    2014-01-01

    Full Text Available Affective dysregulation is at the root of many psychopathologies, including stress induced disorders, anxiety disorders, and depression. The root of these disorders appears to be an attenuated, top-down cognitive control from the prefrontal cortices over the maladaptive subcortical emotional processing. A form of mental training, long-term meditation practice can trigger meditation-specific neuroplastic changes in the brain regions underlying cognitive control and affective regulation, suggesting that meditation can act as a kind of mental exercise to foster affective regulation and possibly a cost-effective intervention in mood disorders. Increasing research has suggested that the cultivation of awareness and acceptance along with a nonjudgmental attitude via meditation promotes adaptive affective regulation. This review examined the concepts of affective regulation and meditation and discussed behavioral and neural evidence of the potential clinical application of meditation. Lately, there has been a growing trend toward incorporating the “mindfulness” component into existing psychotherapeutic treatment. Promising results have been observed thus far. Future studies may consider exploring the possibility of integrating the element of “compassion” into current psychotherapeutic approaches.

  3. Photoionization cross section in a spherical quantum dot: Effects of some parabolic confining electric potentials

    Directory of Open Access Journals (Sweden)

    M. Tshipa

    2017-12-01

    Full Text Available A theoretical investigation of the effects of spatial variation of confining electric potential on photoionization cross section (PCS in a spherical quantum dot is presented. The potential profiles considered here are the shifted parabolic potential and the inverse lateral shifted parabolic potential compared with the well-studied parabolic potential. The primary findings are that parabolic potential and the inverse lateral shifted parabolic potential blue shift the peaks of the PCS while the shifted parabolic potential causes a red shift.

  4. Probenecid potentiates the hyperglycaemic effect but reduces the diuretic effect of frusemide in mice.

    OpenAIRE

    Sandström, P. E.

    1986-01-01

    The effect of probenecid on frusemide-induced diuresis and hyperglycaemia was studied in mice. Probenecid, a known inhibitor of tubular secretion of organic anions in the kidney, strongly reduced the diuretic response to frusemide (25 or 200 mg kg-1 body weight). This effect of probenecid appeared to be dose-dependent up to 240 mg kg-1 body weight, at least at the lower concentration of frusemide. Pretreatment with probenecid (240 mg kg-1 body weight) potentiated the hyperglycaemic effect of ...

  5. SILTATION AND EROSION PROCESSES ON A TRIBUTARY OF LAKE ITAIPU DUE A DAM RESERVOIR

    Directory of Open Access Journals (Sweden)

    Cristiano Poleto

    2012-12-01

    Full Text Available It is known that sediments in the river have their origin from different sources. Therefore, the proportion that each source contributes to the mix varies over time and space, as a result of erosion processes that are ongoing in the basin of contribution. Within this context, both in human actions in urban and rural watersheds generate different rates of sediment production, but mainly with different characteristics or quality. Thus, the fluvial sedimentology should have a broad character within the study area and check all the possible influences of land use and soil. Hydrosedimentological processes are complex and include a disaggregation ("erosion" in the strict definition, transport, sedimentation, consolidation of sediments. Therefore, it is necessary more detailed studies of sediments and their interactions with the environment, considering it as a topic of interest to economic, social and ecological needs of a sustainable management, where they articulate an understanding of the physical and chemical properties of sediments with ecological and hydrological information of the water bodies receiver on a regional scale and thus evaluate the possible scenarios of pollution of water resources. This information will support in decision-making processes for managing the watershed and its water resources. Therefore, this project aims to determine the interference that a hydroelectric plant, together with the lack of proper management of the basin, can cause to the river morphology. The research is conducting a survey of sensitive areas to erode and the influence of a newly installed hydropower in a tributary of Lake Itaipu. Could notice that the removal of riparian vegetation is accelerating the erosion processes at various points of the river, but the agriculture system used in the rural area, without revolving of soil, has reduced the sediment load produced by this source. However, the retention of much of the coarse sediments by the new dam is

  6. An effective pair potential for liquid semiconductor, Se: Structure and ...

    Indian Academy of Sciences (India)

    This model potential is then used to describe through low-order perturbation theory, the structure and related dynamical properties like self-diffusion coefficient and shear viscosity of this complex liquid over a wide range of temperatures. Keywords. Liquid semiconductor; pair potential; structure and dynamical properties.

  7. Potential effects of climate change on Oregon crops

    Science.gov (United States)

    This talk will discuss: 1) potential changes in the Pacific Northwest climate with global climate change, 2) how climate change can affect crops, 3) the diversity of Oregon agriculture, 4) examples of potential response of Oregon crops – especially dryland winter wheat, and 5) br...

  8. Organic photovoltaics: potential fate and effects in the environment.

    Science.gov (United States)

    Zimmermann, Yannick-Serge; Schäffer, Andreas; Hugi, Christoph; Fent, Karl; Corvini, Philippe F-X; Lenz, Markus

    2012-11-15

    In times of dwindling fossil fuels it is particularly crucial to develop novel "green" technologies in order to cover the increasing worldwide demand for energy. Organic photovoltaic solar cells (OPVs) are promising as a renewable energy source due to low energy requirement for production, low resource extraction, and no emission of greenhouse gasses during use. In contrast to silicium-based solar cells, OPVs offer the advantages of light-weight, semi-transparency and mechanical flexibility. As to a possible forthcoming large-scale production, the environmental impact of such OPVs should be assessed and compared to currently best available technologies. For the first time, this review compiles the existing knowledge and identifies gaps regarding the environmental impact of such OPVs in a systematic manner. In this regard, we discuss the components of a typical OPV layer by layer. We discuss the probability of enhanced release of OPV-borne components into the environment during use-phase (e.g. UV- and biodegradation) and end-of-life phase (e.g. incineration and waste disposal). For this purpose, we compiled available data on bioavailability, bioaccumulation, biodegradation, and ecotoxicity. Whereas considerable research has already been carried out concerning the ecotoxicity of certain OPV components (e.g. nanoparticles and fullerenes), others have not been investigated at all so far. In conclusion, there is a general lack of information about fate, behavior as well as potential ecotoxicity of most of the main OPV components and their degradation/transformation products. So far, there is no evidence for a worrying threat coming from OPVs, but since at present, no policy and procedures regarding recycling of OPVs are in action, in particular improper disposal upon end-of-life might result in an adverse effect of OPVs in the environment when applied in large-scale. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Immunotherapy Plus Cryotherapy: Potential Augmented Abscopal Effect for Advanced Cancers

    Directory of Open Access Journals (Sweden)

    Joe Abdo

    2018-03-01

    Full Text Available Since the 1920s the gold standard for treating cancer has been surgery, which is typically preceded or followed with chemotherapy and/or radiation, a process that perhaps contributes to the destruction of a patient’s immune defense system. Cryosurgery ablation of a solid tumor is mechanistically similar to a vaccination where hundreds of unique antigens from a heterogeneous population of tumor cells derived from the invading cancer are released. However, releasing tumor-derived self-antigens into circulation may not be sufficient enough to overcome the checkpoint escape mechanisms some cancers have evolved to avoid immune responses. The potentiated immune response caused by blocking tumor checkpoints designed to prevent programmed cell death may be the optimal treatment method for the immune system to recognize these new circulating cryoablated self-antigens. Preclinical and clinical evidence exists for the complementary roles for Cytotoxic T-lymphocyte-associated protein (CTLA-4 and PD-1 antagonists in regulating adaptive immunity, demonstrating that combination immunotherapy followed by cryosurgery provides a more targeted immune response to distant lesions, a phenomenon known as the abscopal effect. We propose that when the host’s immune system has been “primed” with combined anti-CTLA-4 and anti-PD-1 adjuvants prior to cryosurgery, the preserved cryoablated tumor antigens will be presented and processed by the host’s immune system resulting in a robust cytotoxic CD8+ T-cell response. Based on recent investigations and well-described biochemical mechanisms presented herein, a polyvalent autoinoculation of many tumor-specific antigens, derived from a heterogeneous population of tumor cancer cells, would present to an unhindered yet pre-sensitized immune system yielding a superior advantage in locating, recognizing, and destroying tumor cells throughout the body.

  10. Migratory Behavior of Adult Spring Chinook Salmon in the Willamette River and its Tributaries: Completion report

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, Carl B.

    1994-01-01

    Migration patterns of adult spring chinook salmon above Willamette Falls differed depending on when the fish passed the Falls, with considerable among-fish variability. Early-run fish often terminated their migration for extended periods of time, in association with increased flows and decreased temperatures. Mid-run fish tended to migrate steadily upstream at a rate of 30-40 km/day. Late-run fish frequently ceased migrating or fell back downstream after migrating 10-200 km up the Willamette River or its tributaries; this appeared to be associated with warming water during summer and resulted in considerable mortality. Up to 40% of the adult salmon entering the Willamette River System above Willamette Falls (i.e. counted at the ladder) may die before reaching upriver spawning areas. Up to 10% of the fish passing up over Willamette Falls may fall-back below the Falls; some migrate to the Columbia River or lower Willamette River tributaries. If rearing conditions at hatcheries affect timing of adult returns because of different juvenile development rates and improper timing of smolt releases, then differential mortality in the freshwater segment of the adult migrations may confound interpretation of studies evaluating rearing practices.

  11. Morphological variation among populations of Hemigrammus coeruleus (Characiformes: Characidae in a Negro River tributary, Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Henrique Lazzarotto

    2017-03-01

    Full Text Available ABSTRACT We explored patterns of phenotypic variation in Hemigrammus coeruleus from the Unini River basin, a blackwater river in the Brazilian Amazon. Geometric morphometrics was used to evaluate variation in body shape among populations from four tributaries (UN2-UN5. We found no evidence for sexual dimorphism in body size and shape. However, morphological differences among populations were detected as the analyses recovered significant groups corresponding to each sub-basin, with some overlap among them. The populations from UN2, UN3 and UN5 had more elongate bodies than fish from UN4. The most morphologically divergent population belonged to UN4, the tributary with the most divergent environmental conditions and the only one with seasonally-muddy waters. The morphological variation found among these populations is likely due to phenotypic plasticity or local adaptation, arising as a product of divergent ecological selection pressures among sub-basins. This work constitutes one of the first to employ a population-level geometric morphometric approach to assess phenotypic variation in Amazonian fishes. This method was able to distinguish subtle differences in body morphology, and its use with additional species can bring novel perspectives on the evaluation of general patterns of phenotypic differentiation in the Amazon.

  12. Plastic Debris in 29 Great Lakes Tributaries: Relations to Watershed Attributes and Hydrology.

    Science.gov (United States)

    Baldwin, Austin K; Corsi, Steven R; Mason, Sherri A

    2016-10-04

    Plastic debris is a growing contaminant of concern in freshwater environments, yet sources, transport, and fate remain unclear. This study characterized the quantity and morphology of floating micro- and macroplastics in 29 Great Lakes tributaries in six states under different land covers, wastewater effluent contributions, population densities, and hydrologic conditions. Tributaries were sampled three or four times each using a 333 μm mesh neuston net. Plastic particles were sorted by size, counted, and categorized as fibers/lines, pellets/beads, foams, films, and fragments. Plastics were found in all 107 samples, with a maximum concentration of 32 particles/m 3 and a median of 1.9 particles/m 3 . Ninety-eight percent of sampled plastic particles were less than 4.75 mm in diameter and therefore considered microplastics. Fragments, films, foams, and pellets/beads were positively correlated with urban-related watershed attributes and were found at greater concentrations during runoff-event conditions. Fibers, the most frequently detected particle type, were not associated with urban-related watershed attributes, wastewater effluent contribution, or hydrologic condition. Results from this study add to the body of information currently available on microplastics in different environmental compartments, including unique contributions to quantify their occurrence and variability in rivers with a wide variety of different land-use characteristics while highlighting differences between surface samples from rivers compared with lakes.

  13. Distribution of agrochemicals in the lower Mississippi River and its tributaries

    Science.gov (United States)

    Pereira, W.E.; Rostad, C.E.; Leiker, T.J.

    1990-01-01

    The Mississippi River and its tributaries drain extensive agricultural regions of the Mid-Continental United States. Millions of pounds of herbicides are applied annually in these areas to improve crop yields. Many of these compounds are transported into the river from point and nonpoint sources, and eventually are discharged into the Gulf of Mexico. Studies being conducted by the U.S. Geological Survey along the lower Mississippi River and its major tributaries, representing a 2000 km river reach, have confirmed that several triazine and acetanilide herbicides and their degradation products are ubiquitous in this riverine system. These compounds include atrazine and its degradation products desethyl and desisopropylatrazine, cyanazine, simazine, metolachlor, and alachlor and its degradation products 2-chloro-2',6'-diethylacetanilide, 2-hydroxy-2',6-diethylacetanilide and 2,6-diethylaniline. Loads of these compounds were determined at 16 different sampling stations. Stream-load calculations provided information concerning (a) conservative or nonconservative behavior of herbicides; (b) point sources or nonpoint sources; (c) validation of sampling techniques; and (d) transport past each sampling station.

  14. Plastic debris in 29 Great Lakes tributaries: Relations to watershed attributes and hydrology

    Science.gov (United States)

    Baldwin, Austin K.; Corsi, Steven; Mason, Sherri A.

    2016-01-01

    Plastic debris is a growing contaminant of concern in freshwater environments, yet sources, transport, and fate remain unclear. This study characterized the quantity and morphology of floating micro- and macroplastics in 29 Great Lakes tributaries in six states under different land covers, wastewater effluent contributions, population densities, and hydrologic conditions. Tributaries were sampled three or four times each using a 333 μm mesh neuston net. Plastic particles were sorted by size, counted, and categorized as fibers/lines, pellets/beads, foams, films, and fragments. Plastics were found in all 107 samples, with a maximum concentration of 32 particles/m3 and a median of 1.9 particles/m3. Ninety-eight percent of sampled plastic particles were less than 4.75 mm in diameter and therefore considered microplastics. Fragments, films, foams, and pellets/beads were positively correlated with urban-related watershed attributes and were found at greater concentrations during runoff-event conditions. Fibers, the most frequently detected particle type, were not associated with urban-related watershed attributes, wastewater effluent contribution, or hydrologic condition. Results from this study add to the body of information currently available on microplastics in different environmental compartments, including unique contributions to quantify their occurrence and variability in rivers with a wide variety of different land-use characteristics while highlighting differences between surface samples from rivers compared with lakes.

  15. Long-term decreases in phosphorus and suspended solids, but not nitrogen, in six upper Mississippi River tributaries, 1991–2014

    Science.gov (United States)

    Kreiling, Rebecca; Houser, Jeff N.

    2016-01-01

    Long-term trends in tributaries provide valuable information about temporal changes in inputs of nutrients and sediments to large rivers. Data collected from 1991 to 2014 were used to investigate trends in total nitrogen (TN), total phosphorus (TP), nitrate (NO3–N), soluble-reactive P (SRP), and total suspended solids (TSS) in the following six tributaries of the upper Mississippi River: Cannon (CaR; Minnesota (MN)), Maquoketa (MR; Iowa (IA)), Wapsipinicon (WR; IA), Cuivre (CuR; Missouri (MO)), Chippewa (ChR; Wisconsin (WI)), and Black (BR; WI) rivers. Weighted regression on time discharge and season was used to statistically remove effects of random variation in discharge from estimated trends in flow-normalized concentrations and flux. Concentration and flux of TSS declined in all six rivers. Concentration of P declined in four of the rivers, and P flux declined in five rivers. Concentration and flux of N exhibited small changes relative to TP. TN concentration and flux did not change substantially in four of the rivers and decreased in two (ChR, CuR). Nitrate concentration and flux increased in three rivers (ChR, BR, CaR) and remained relatively constant in the other three rivers. General declines in P and TSS suggest that improvements in agricultural land management, such as the adoption of conservation tillage and enrollment of vulnerable acreage into the Conservation Reserve Program, may have reduced surface runoff; similar reductions in N were not observed.

  16. Complex influences of low-head dams and artificial wetlands on fishes in a Colorado River tributary system

    Science.gov (United States)

    Beatty, R.J.; Rahel, F.J.; Hubert, W.A.

    2009-01-01

    Low-head dams in arid regions restrict fish movement and create novel habitats that have complex effects on fish assemblages. The influence of low-head dams and artificial wetlands on fishes in Muddy Creek, a tributary of the Colorado River system in the USA was examined. Upstream, fish assemblages were dominated by native species including two species of conservation concern, bluehead sucker, Catostomus discobolus Cope, and roundtail chub, Gila robusta Baird and Girard. The artificial wetlands contained almost exclusively non-native fathead minnow, Pimephales promelas Rafinesque, and white sucker, Catostomus commersonii (Lacep??de). Downstream, fish assemblages were dominated by non-native species. Upstream spawning migrations by non-native white suckers were blocked by dams associated with the wetlands. However, the wetlands do not provide habitat for native fishes and likely inhibit fish movement. The wetlands appear to be a source habitat for non-native fishes and a sink habitat for native fishes. Two non-native species, sand shiner, Notropis stramineus (Cope), and redside shiner, Richardsonius balteatus (Richardson), were present only downstream of the wetlands, suggesting a beneficial role of the wetlands in preventing upstream colonisation by non-native fishes. ?? 2009 Blackwell Publishing Ltd.

  17. Matter-wave bright solitons in effective bichromatic lattice potentials

    Indian Academy of Sciences (India)

    wave bright solitons in bichromatic lattice potentials are considered and their dynamics for different lattice environments are studied. ... Scientific Computing Laboratory, Institute of Physics Belgrade, Pregrevica 118, 11080 Belgrade, Serbia ...

  18. Potential environmental effects of the leading edge hydrokinetic energy technology.

    Science.gov (United States)

    2017-05-01

    The Volpe Center evaluated potential environmental challenges and benefits of the ARPA-E funded research project, Marine Hydrokinetic Energy Harvesting Using Cyber-Physical Systems, led by Brown University. The Leading Edge research team develo...

  19. Proprioceptive event related potentials: gating and task effects

    DEFF Research Database (Denmark)

    Arnfred, Sidse M

    2005-01-01

    The integration of proprioception with vision, touch or audition is considered basic to the developmental formation of perceptions, conceptual objects and the creation of cognitive schemes. Thus, mapping of proprioceptive information processing is important in cognitive research. A stimulus...... of a brisk change of weight on a hand held load elicit a proprioceptive evoked potential (PEP). Here this is used to examine early and late information processing related to weight discrimination by event related potentials (ERP)....

  20. Magnetoconductance of a hybrid quantum ring: Effects of antidot potentials

    OpenAIRE

    Nammee Kim; Dae-Han Park; Heesang Kim

    2016-01-01

    The electronic structures and two-terminal magnetoconductance of a hybrid quantum ring are studied. The backscattering due to energy-resonance is considered in the conductance calculation. The hybrid magnetic-electric quantum ring is fabricated by applying an antidot electrostatic potential in the middle of a magnetic quantum dot. Electrons are both magnetically and electrically confined in the plane. The antidot potential repelling electrons from the center of the dot plays a critical role i...

  1. Superfield approach to calculation of effective potential in supersymmetric field theories

    International Nuclear Information System (INIS)

    Bukhbinder, I.L.; Kuzenko, S.M.; Yarevskaya, Zh.V.

    1993-01-01

    Superfield method of computing effective potential in supersymmetric field theories is suggested. The one-loop effective potential of the Wess-Zumino model is found. The prescription for obtaining multi-loop corrections is described

  2. Dual effects of sodium sulfide on the flotation behavior of chalcopyrite: I. Effect of pulp potential

    Science.gov (United States)

    Taheri, Bijan; Abdollahy, Mahmoud; Tonkaboni, Sied Ziaedin Shafaei; Javadian, Soheyla; Yarahmadi, Mohammadreza

    2014-05-01

    This study explores the flotation behavior of chalcopyrite in the presence of different concentrations of sodium sulfide (Na2S·9H2O) at pH 12 under controlled potential conditions. It was observed that the flotation of chalcopyrite is not depressed completely when the pulp potential is low, even at high concentrations of sodium sulfide, i.e., 10-1-10-2 mol/L. However, a partial and controlled oxidation of pulp does enhance the effectiveness of sodium sulfide on the depression of chalcopyrite. Characterization of the chalcopyrite particle surface by X-ray photoelectron spectroscopy allowed the identification of hydrophilic and hydrophobic surface species, which are responsible for the depression and flotation of chalcopyrite. Changes in pulp potential were found to be an effective float controlling parameter, by which Na2S can be used to initiate or depress the flotation behavior of chalcopyrite.

  3. Predicted riparian vegetation - Potential for Habitat Improvement in the Columbia River Basin

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basin-wide analysis of potential to improve tributary habitats in the Columbia River basin through restoration of habitat-forming processes. Identification of...

  4. Predicted channel types - Potential for Habitat Improvement in the Columbia River Basin

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basin-wide analysis of potential to improve tributary habitats in the Columbia River basin through restoration of habitat-forming processes. Identification of...

  5. Concentration, flux, and the analysis of trends of total and dissolved phosphorus, total nitrogen, and chloride in 18 tributaries to Lake Champlain, Vermont and New York, 1990–2011

    Science.gov (United States)

    Medalie, Laura

    2013-01-01

    Annual concentration, flux, and yield for total phosphorus, dissolved phosphorus, total nitrogen, and chloride for 18 tributaries to Lake Champlain were estimated for 1990 through 2011 using a weighted regression method based on time, tributary streamflows (discharges), and seasonal factors. The weighted regression method generated two series of daily estimates of flux and concentration during the period of record: one based on observed discharges and a second based on a flow-normalization procedure that removes random variation due to year-to-year climate-driven effects. The flownormalized estimate for a given date is similar to an average estimate of concentration or flux that would be made if all of the observed discharges for that date were equally likely to have occurred. The flux bias statistic showed that 68 of the 72 flux regression models were minimally biased. Temporal trends in the concentrations and fluxes were determined by calculating percent changes in flow-normalized annual fluxes for the full period of analysis (1990 through 2010) and for the decades 1990–2000 and 2000–2010. Basinwide, flow-normalized total phosphorus flux decreased by 42 metric tons per year (t/yr) between 1990 and 2010. This net result reflects a basinwide decrease in flux of 21 metric tons (t) between 1990 and 2000, followed by a decrease of 20 t between 2000 and 2010; both results were largely influenced by flux patterns in the large tributaries on the eastern side of the basin. A comparison of results for total phosphorus for the two separate decades of analysis found that more tributaries had decreasing concentrations and flux rates in the second decade than the first. An overall reduction in dissolved phosphorus flux of 0.7 t/yr was seen in the Lake Champlain Basin during the full period of analysis. That very small net change in flux reflects substantial reductions between 1990 and 2000 from eastern tributaries, especially in Otter Creek and the LaPlatte and Winooski

  6. Water quality of the St. Clair River, Lake St. Clair, and their U.S. tributaries, 1946-2005

    Science.gov (United States)

    Healy, Denis F.; Chambers, Douglas B.; Rachol, Cynthia M.; Jodoin, Richard S.

    2007-01-01

    860 mg/L for all study-area streams, with the six largest being in the Belle River Basin. Higher chloride concentrations were increasingly common from 2002 to 2005. The urban minor river basins had the highest median specific conductance, whereas the agricultural Pine River Basin had the lowest median specific conductance. The median values of BOD for the five basins in the study area ranged from 2.4 mg/L for the Pine River Basin to 3.2 mg/L for the Black and Clinton River Basins, whereas the median for the St. Clair River was 0.5 mg/L. In 1985, the highest concentrations of pesticides were found in samples from the mouth of the Clinton River; however, in 1996–98, the majority of high pesticide concentrations were found in samples from the Black River. Changing land-use patterns, specifically conversion of agricultural lands to urban/residential lands in the Clinton River Basin, may explain this difference. Trend analysis was done for four stream sites where adequate data were available. These analyses identified no significant water-quality changes at a stream site on the Black River, where land-use patterns have changed little in the past few decades. This stands in marked contrast to trend analysis for three stream sites in the Clinton River Basin, which has undergone significant land-use change. The changes at the Clinton River stream sites, ranging from 5 to 13 significant trends, were generally decreases in nutrients and increases in total dissolved solids (TDS) and chloride. The greater flow volume of the St. Clair River/Lake St. Clair waterway is able to assimilate incoming dissolved and suspended constituents from tributaries with little effect upon its overall water quality, although incomplete mixing may result in localized water-quality impairment downstream from tributary confluences. Mixing effects on Lake St. Clair water quality was also demonstrated in analysis of Escherichia coli (E. coli) data collected at paired nearshore/offshore sites, which

  7. Effects of Temperature and Corrosion Potential on SCC

    Science.gov (United States)

    Andresen, Peter L.; Seeman, Russell A.

    This study reinforces the expectation that a consistent benefit of low corrosion potential is achievable at intermediate temperatures associated with BWR start up. Such low corrosion potentials can probably only be achieved using NobleChem™ and injection of H2 or other reductants such as hydrazine or carbohydrazide because very low residual levels of O2 can elevate the corrosion potential. The high growth rates that occur during start up merit mitigation, although this study did not find growth rates that were orders of magnitude higher than at 288 °C. However, this study did not attempt to simulate all aspects of start up, especially the sources of dynamic strain such as differential thermal expansion, which can be estimated by are not known.

  8. Magnetoconductance of a hybrid quantum ring: Effects of antidot potentials

    Directory of Open Access Journals (Sweden)

    Nammee Kim

    2016-05-01

    Full Text Available The electronic structures and two-terminal magnetoconductance of a hybrid quantum ring are studied. The backscattering due to energy-resonance is considered in the conductance calculation. The hybrid magnetic-electric quantum ring is fabricated by applying an antidot electrostatic potential in the middle of a magnetic quantum dot. Electrons are both magnetically and electrically confined in the plane. The antidot potential repelling electrons from the center of the dot plays a critical role in the energy spectra and magnetoconductance. The angular momentum transition in the energy dispersion and the magnetoconductance behavior are investigated in consideration of the antidot potential variation. Results are shown using a comparison of the results of the conventional magnetic quantum dot.

  9. Level II scour analysis for Bridge 59 (NWPCVT01050059) on State Route 105 crossing an unnamed Mud Creek Tributary, Newport, Vermont

    Science.gov (United States)

    Boehmler, Erick M.; Ivanoff, Michael A.

    1996-01-01

    This report provides the results of a detailed Level II analysis of scour potential at structure NWPCVT01050059 on state route 105 crossing an unnamed Mud Creek tributary, Newport, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S. Department of Transportation, 1993). Results of a Level I scour investigation also are included in Appendix E of this report. A Level I investigation provides a qualitative geomorphic characterization of the study site. Information on the bridge, gleaned from Vermont Agency of Transportation (VTAOT) files, was compiled prior to conducting Level I and Level II analyses and is found in Appendix D.

  10. Diatomic Molecules Effective Potential for an Harmonic Oscillator ...

    African Journals Online (AJOL)

    A model anharmonic potential was considered and was used in the Schrödinger time independent wave equation to describe a carbon monoxide molecule. Central difference scheme was used in approximating the derivative term in the Schrödinger equation leading to a tri-diagonal band system of equation. The method of ...

  11. Potential effects of earthworms on leaf-chewer performance

    NARCIS (Netherlands)

    Newington, J.E.; Setälä, H.; Bezemer, T.M.; Jones, T.H.

    2004-01-01

    Detritivores affect plant performance and therefore have the potential indirectly to affect above-ground herbivore populations. 2. In a microcosm study we asked whether changes in the performance of two plant species, Cardamine hirsuta L. and Veronica persica Poiret., arising from the activity of

  12. Lake Victoria's Water Budget and the Potential Effects of Climate ...

    African Journals Online (AJOL)

    This paper presents the Lake Victoria water budget for the period 1950-2004 and findings of a study on potential climate change impact on the lake's Hydrology through the 21st Century. The mass balance components are computed from measured and simulated data. A2 and B2 emission scenarios of the Special Report ...

  13. Potential Effects of the Adoption and Implementstion of International ...

    African Journals Online (AJOL)

    It presents the results from a questionnaire survey of a sample of accounting lecturers, auditors and accountants. The data were analyzed using the Chi Square. The study found that International Financial Reporting Standards have the potential for yielding greater benefits than current GAAP, improve business performance ...

  14. Effect of electrodeposition potential on composition and morphology ...

    Indian Academy of Sciences (India)

    ing the concentration in the solution as well as deposition potential. ... of complexing agent was the best choice. pH of the solu- tion was adjusted to 2·0 by adding drops of concentrated hydrochloric acid. CV was carried out in the range of poten- tials from −1·2 ... Figure 1(a) shows voltammogram of the base solution which.

  15. Eutrophication potential of Payette Lake, Idaho

    Science.gov (United States)

    Woods, Paul F.

    1997-01-01

    Payette Lake was studied during water years 1995-96 to determine the 20.5-square-kilometer lake's assimilative capacity for nutrients and, thus, its eutrophication potential. The study included quantification of hydrologic and nutrient budgets, characterization of water quality in the limnetic and littoral zones, development of an empirical nutrient load/lake response model, and estimation of the limnological effects of a large-scale forest fire in the lake's 373-square-kilometer watershed during the autumn of 1994. Streamflow from the North Fork Payette River, the lake's primary tributary, delivered about 73 percent of the lake's inflow over the 2 years. Outflow from the lake, measured since 1908, was 128 and 148 percent of the long-term average in 1995 and 1996, respectively. The larger volumes of outflow reduced the long-term average water-

  16. Sources and sinks of microplastics in Canadian Lake Ontario nearshore, tributary and beach sediments.

    Science.gov (United States)

    Ballent, Anika; Corcoran, Patricia L; Madden, Odile; Helm, Paul A; Longstaffe, Fred J

    2016-09-15

    Microplastics contamination of Lake Ontario sediments is investigated with the aim of identifying distribution patterns and hotspots in nearshore, tributary and beach depositional environments. Microplastics are concentrated in nearshore sediments in the vicinity of urban and industrial regions. In Humber Bay and Toronto Harbour microplastic concentrations were consistently >500 particles per kg dry sediment. Maximum concentrations of ~28,000 particles per kg dry sediment were determined in Etobicoke Creek. The microplastic particles were primarily fibres and fragments microplastics in terms of how and where to implement preventative measures to reduce the contaminant influx. Although the impacts of microplastics contamination on ecosystem health and functioning is uncertain, understanding, monitoring and preventing further microplastics contamination in Lake Ontario and the other Great Lakes is crucial. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Yakima Tributary Access and Habitat Program, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Myra, D.; Ready, C.

    2003-12-01

    The Yakima Tributary Access and Habitat Program (YTAHP) was organized to restore salmonid passage to Yakima tributaries that historically supported salmonids and to improve habitat in areas where access is restored. This program intends to (a) screen unscreened diversion structures to prevent fish entrainment into artificial waterways; (b) provide for fish passage at man-made barriers, such as diversion dams, culverts, siphons and bridges; and (c) provide information and assistance to landowners interested in to contributing to the improvement of water quality, water reliability and stream habitat. The YTAHP developed from a number of groups actively engaged in watershed management, and/or habitat restoration within the Yakima River Basin. These groups include the Washington State Fish and Wildlife (WDFW), Kittitas County Conservation District (KCCD), North Yakima Conservation District (NYCD), Kittitas County Water Purveyors (KCWP), and Ahtanum Irrigation District (AID). The US Bureau of Reclamation (Reclamation) and Yakama Nation (YN) both participated in the development of the objectives of YTAHP. Other entities that will be involved during permitting or project review may include the YN, the federal Natural Resources Conservation Service (NRCS), the US Fish and Wildlife Service (USFWS), the National Marine Fisheries Service (NMFS), and US Army Corps of Engineers (COE). The objectives of YTAHP are listed below and also include subtasks detailed in the report: (1) Conduct Early Action Projects; (2) Review Strategic Plan; (3) Restore Access, including stream inventory, prioritization, implementation; and (4) Provide opportunities to improve habitat and conserve resources. The BPA YTAHP funding supported activities of the program which are described in this report. These activities are primarily related to objective 1 (conduct early action projects) and parts of objectives 2-4. The work supported by YTAHP funding will support a series of scheduled projects and be

  18. Proprioceptive event related potentials: gating and task effects

    DEFF Research Database (Denmark)

    Arnfred, Sidse Marie

    2005-01-01

    OBJECTIVE: The integration of proprioception with vision, touch or audition is considered basic to the developmental formation of perceptions, conceptual objects and the creation of cognitive schemes. Thus, mapping of proprioceptive information processing is important in cognitive research....... A stimulus of a brisk change of weight on a hand held load elicit a proprioceptive evoked potential (PEP). Here this is used to examine early and late information processing related to weight discrimination by event related potentials (ERP). METHODS: A gating paradigm having 1s between the proprioceptive...... stimuli of 100 g weight increase was recorded in 12 runs of 40 pairs and an 1:4 oddball task of discriminating between 40 and 100 g weight increase was both recorded in 24 healthy men. The subjects were stratified in 3 groups according to their discrimination errors. RESULTS: The proprioceptive event...

  19. An interatomic potential model for carbonates allowing for polarization effects

    International Nuclear Information System (INIS)

    Birse, S.E.A.; Archer, T.D.; Dove, Martin T.; Cygan, Randall Timothy; Gale, Julian D.; Redern, Simon A.T.

    2003-01-01

    An empirical model for investigating the behavior of CaCO 3 polymorphs incorporating a shell model for oxygen has been created. The model was constructed by fitting to: the structure of aragonite and calcite; their elastic, static and high-frequency dielectric constants; phonon frequencies at the wave vectors (1/2 0 2) and (0 0 0) of calcite; and vibrational frequencies of the carbonate deformation modes of calcite. The high-pressure phase transition between calcite I and II is observed. The potentials for the CO 3 group were transferred to other carbonates, by refitting the interaction between CO 3 and the cation to both the experimental structures and their bulk modulus, creating a set of potentials for calculating the properties of a wide range of carbonate materials. Defect energies of substitutional cation defects were analyzed for calcite and aragonite phases. The results were rationalized by studying the structure of calcite and aragonite in greater detail.

  20. Newer Approaches to Identify Potential Untoward Effects in Functional Foods.

    Science.gov (United States)

    Marone, Palma Ann; Birkenbach, Victoria L; Hayes, A Wallace

    2016-01-01

    Globalization has greatly accelerated the numbers and variety of food and beverage products available worldwide. The exchange among greater numbers of countries, manufacturers, and products in the United States and worldwide has necessitated enhanced quality measures for nutritional products for larger populations increasingly reliant on functionality. These functional foods, those that provide benefit beyond basic nutrition, are increasingly being used for their potential to alleviate food insufficiency while enhancing quality and longevity of life. In the United States alone, a steady import increase of greater than 15% per year or 24 million shipments, over 70% products of which are food related, is regulated under the Food and Drug Administration (FDA). This unparalleled growth has resulted in the need for faster, cheaper, and better safety and efficacy screening methods in the form of harmonized guidelines and recommendations for product standardization. In an effort to meet this need, the in vitro toxicology testing market has similarly grown with an anticipatory 15% increase between 2010 and 2015 of US$1.3 to US$2.7 billion. Although traditionally occupying a small fraction of the market behind pharmaceuticals and cosmetic/household products, the scope of functional food testing, including additives/supplements, ingredients, residues, contact/processing, and contaminants, is potentially expansive. Similarly, as functional food testing has progressed, so has the need to identify potential adverse factors that threaten the safety and quality of these products. © The Author(s) 2015.

  1. University students' psychopathology: correlates and the examiner's potential bias effect

    Directory of Open Access Journals (Sweden)

    Helena Espirito Santo

    2015-02-01

    Aims: the main objective was to verify if there is a difference on psychopathological symptoms between two groups questioned by two different examiners, controlling for the potential role of social desirability, and other potential covariates. Additionally, we want to assess the level of psychopathology and its socio-demographic correlates.Methods: 185 Coimbra's university students completed the Brief Symptom Inventory/BSI and the Marlowe-Crowne Social Desirability Scale. In one group the examiner was of the same age and academic status as the students, while in the other group the examiner was older and a teacher. We studied the psychopathological correlates with Pearson, point-biserial correlations, and qui-square analyses, and we controlled the potential role of covariates through Quade non-parametric ANCOVAs. Results: The level of distress was lower in comparison with other investigations. Women had higher level of distress and more symptoms of somatization, anxiety, phobic anxiety, obsessive-compulsion, and depression. The students that live a higher distance from home had more anxiety and obsessive-compulsive symptoms. The group assessed by the younger examiner scored higher in distress and in some BSI factors, and had lower levels on social desirability. Conclusions: Sex and distance from home seem important factors for university students' mental health. However, the examiner does have an influence in the evaluation, probably because of social desirability, suggesting that the examiner's characteristics should be given in investigations involving university students.

  2. Analysis of some potential social effects of four coal technologies

    Energy Technology Data Exchange (ETDEWEB)

    Walker, C.A.; Gould, L.C.

    1980-09-01

    This is an analysis of the potential social impacts of four coal technologies: conventional combustion, fluidized-bed combustion, liquifaction, and gasification. Because of their flexibility, and the abundance and relatively low costs of coal, the potential benefits of these technologies would seem to outweigh their potential social costs, both in the intermediate and long term. Nevertheless, the social costs of a coal industry are far more obscure and hard to quantify than the benefits. In general, however, it maybe expected that those technologies that can be deployed most quickly, that provide fuels that can substitute most easily for oil and natural gas, that are the cheapest, and that are the most thermally efficient will minimize social costs most in the intermediate term, while technologies that can guide energy infrastructure changes to become the most compatable with the fuels that will be most easily derived from inexhaustible sources (electricity and hydrogen) will minimize social costs most in the long run. An industry structured to favor eastern over western coal and plant sites in moderate sized communities, which could easily adapt to inexhaustible energy technologies (nuclear or solar) in the future, would be favored in either time period.

  3. Acute and Sub-Chronic Toxicity Potential Effects of Alchornea ...

    African Journals Online (AJOL)

    The open field test showed that sub-chronic administration increased rearing behavior significantly at the dose of 250 mg/kg/28 days but had no effect on grooming. In conclusion, the ethanolic extract has no toxicological effect as observed on hematological, biochemical and histopathological parameters even at the ...

  4. On the path of plumes of the Río De La Plata Estuary main tributaries and their mixing scales

    Directory of Open Access Journals (Sweden)

    Claudia G Simionato

    2009-12-01

    Full Text Available With a length of 300 km and a width that narrows from 220 km at its mouth to 40 km at its upper end, the Río de la Plata is one of the largest estuaries of the world. Its three main tributaries -contributing to a total mean runoff of 22,000 m³ s-1- have different properties and are object of diverse environmental impact due to dissimilar development conditions on their shores. The knowledge of the paths of the plumes of those tributaries along the estuary and their mixing scales is necessary for management purposes. In this paper, advection-diffusion equations for passive tracers are coupled to the three-dimensional Hamburg Shelf Ocean Model and validated by means of a case study. Then, simulations in which each tributary is characterized by a different dye tracer are done for scenarios resulting of the combination of diverse characteristic atmospheric forcing and runoff conditions. The impact of bathymetry and Earth's rotation on plumes paths and mixing is also evaluated. Results indicate that, for mean to low discharge conditions, the path of the waters of the tributaries is in the form of two main plumes. The different water speeds of both tributaries, the presence of a bend immediately after their confluence and the varying geometry and bathymetry of the estuary favor a rapid mixing between the Uruguay and Paraná Guazú-Bravo waters, which then flow along the northern portion of the upper estuary channel. The Paraná de las Palmas waters, instead, occupy the southern shallow region of Playa Honda in the upper estuary and then flow following the southern coast. Downstream Colonia, at the intermediate estuary, the occurrence of another large bend and a change in bathymetric features force the flow to concentrate in the central part of the estuary and favor further mixing between the plumes. For high discharge conditions the northern part of the upper estuary is divided into two regions, one with a larger concentration of Uruguay waters

  5. Potential Effects of Cannabidiol as a Wake-Promoting Agent

    Science.gov (United States)

    Murillo-Rodríguez, Eric; Sarro-Ramírez, Andrea; Sánchez, Daniel; Mijangos-Moreno, Stephanie; Tejeda-Padrón, Alma; Poot-Aké, Alwin; Guzmán, Khalil; Pacheco-Pantoja, Elda; Arias-Carrión, Oscar

    2014-01-01

    Over the last decades, the scientific interest in chemistry and pharmacology of cannabinoids has increased. Most attention has focused on ∆9-tetrahydrocannabinol (∆9-THC) as it is the psychoactive constituent of Cannabis sativa (C. sativa). However, in previous years, the focus of interest in the second plant constituent with non-psychotropic properties, cannabidiol (CBD) has been enhanced. Recently, several groups have investigated the pharmacological properties of CBD with significant findings; furthermore, this compound has raised promising pharmacological properties as a wake-inducing drug. In the current review, we will provide experimental evidence regarding the potential role of CBD as a wake-inducing drug. PMID:24851090

  6. Potential Effects of Desalinated Seawater on Arteriosclerosis in Rats.

    Science.gov (United States)

    Duan, Lian; Zhang, Li Xia; Zhang, Shao Ping; Kong, Jian; Zhi, Hong; Zhang, Ming; Lu, Kai; Zhang, Hong Wei

    2017-10-01

    To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blood calcium, magnesium, and arteriosclerosis-related indicators were investigated. Female rats treated with desalinated seawater for 180 days showed lower magnesium levels than the control rats (P seawater for 360 days (P seawater, and no increase in risk of arteriosclerosis was observed. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  7. Quantum fluctuations and dynamical chaos: An effective potential approach

    International Nuclear Information System (INIS)

    Matinyan, S.G.; Mueller, B.

    1997-01-01

    The authors discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using the example of massless scalar electrodynamics, they show how the radiatively induced spontaneous symmetry breaking stabilizes the vacuum state against chaos, and they speculate that monopole condensation can have the same effect in non-Abelian gauge theories

  8. 33 CFR 334.450 - Cape Fear River and tributaries at Sunny Point Army Terminal, Brunswick County, N.C.; restricted...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Cape Fear River and tributaries... AND RESTRICTED AREA REGULATIONS § 334.450 Cape Fear River and tributaries at Sunny Point Army Terminal, Brunswick County, N.C.; restricted area. (a) The area. That portion of Cape Fear River due west of the main...

  9. A Three-Year Study of Ichyoplankton in Coastal Plains Reaches of the Savannah River Site and its Tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Martin, D.

    2007-03-05

    Altering flow regimes of rivers has large effects on native floras and faunas because native species are adapted to the natural flow regime, many species require lateral connectivity with floodplain habitat for feeding or spawning, and the change in regime often makes it possible for invasive species to replace natives (Bunn & Arthington 2002). Floodplain backwaters, both permanent and temporary, are nursery areas for age 0+ fish and stable isotope studies indicate that much of the productivity that supports fish larvae is autochthonous to these habitats (Herwig et al. 2004). Limiting access by fish to floodplain habitat for feeding, spawning and nursery habitat is one of the problems noted with dams that regulate flow in rivers and is considered to be important as an argument to remove dams and other flow regulating structures from rivers (Shuman 1995; Bednarek 2001). While there have been a number of studies in the literature about the use of floodplain habitat for fish reproduction (Copp 1989; Killgore & Baker 1996; Humphries, et al. 1999; Humphries and Lake 2000; Crain et al. 2004; King 2004) there have been only a few studies that examined this aspect of stream ecology in more than a cursory way. The study reported here was originally designed to determine whether the Department of Energy's (DOE) Savannah River Site was having a negative effect on fish reproduction in the Savannah River but its experimental design allowed examination of the interactions between the river, the floodplain and the tributaries entering the Savannah River across this floodplain. This study is larger in length of river covered than most in the literature and because of its landscape scale may be in important indicator of areas where further study is required.

  10. Investigation on the 1970s and 1980s droughts in four tributaries of the Niger River Basin (West Africa).

    CSIR Research Space (South Africa)

    Badou, DF

    2015-07-01

    Full Text Available this question, we evaluated spatio-temporal pattern of rainfall and runoff in four tributaries (Sota, Alibori, Mekrou and Kompa-gorou) of the Niger River basin, covering a total area of 40,000km2 for the period 1971 to 2010. First, decadal rainfall variability...

  11. Potential Cost-Effective Opportunities for Methane Emission Abatement

    Energy Technology Data Exchange (ETDEWEB)

    Warner, Ethan [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States); Steinberg, Daniel [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States); Hodson, Elke [U.S. Department of Energy, Washington, DC (United States); Heath, Garvin [Joint Inst. for Strategic Energy Analysis, Golden, CO (United States)

    2015-08-01

    The energy sector was responsible for approximately 84% of carbon dioxide equivalent (CO2e) greenhouse gas (GHG) emissions in the U.S. in 2012 (EPA 2014a). Methane is the second most important GHG, contributing 9% of total U.S. CO2e emissions. A large portion of those methane emissions result from energy production and use; the natural gas, coal, and oil industries produce approximately 39% of anthropogenic methane emissions in the U.S. As a result, fossil-fuel systems have been consistently identified as high priority sectors to contribute to U.S. GHG reduction goals (White House 2015). Only two studies have recently attempted to quantify the abatement potential and cost associated with the breadth of opportunities to reduce GHG emissions within natural gas, oil, and coal supply chains in the United States, namely the U.S. Environmental Protection Agency (EPA) (2013a) and ICF (2014). EPA, in its 2013 analysis, estimated the marginal cost of abatement for non-CO2 GHG emissions from the natural gas, oil, and coal supply chains for multiple regions globally, including the United States. Building on this work, ICF International (ICF) (2014) provided an update and re-analysis of the potential opportunities in U.S. natural gas and oil systems. In this report we synthesize these previously published estimates as well as incorporate additional data provided by ICF to provide a comprehensive national analysis of methane abatement opportunities and their associated costs across the natural gas, oil, and coal supply chains. Results are presented as a suite of marginal abatement cost curves (MACCs), which depict the total potential and cost of reducing emissions through different abatement measures. We report results by sector (natural gas, oil, and coal) and by supply chain segment - production, gathering and boosting, processing, transmission and storage, or distribution - to facilitate identification of which sectors and supply chain

  12. Pollution effects on fisheries — potential management activities

    Science.gov (United States)

    Sindermann, C. J.

    1980-03-01

    Management of ocean pollution must be based on the best available scientific information, with adequate consideration of economic, social, and political realities. Unfortunately, the best available scientific information about pollution effects on fisheries is often fragmentary, and often conjectural; therefore a primary concern of management should be a critical review and assessment of available factual information about effects of pollutants on fish and shellfish stocks. A major problem in any such review and assessment is the separation of pollutant effects from the effects of all the other environmental factors that influence survival and well-being of marine animals. Data from long-term monitoring of resource abundance, and from monitoring of all determinant environmental variables, will be required for analyses that lead to resolution of the problem. Information must also be acquired about fluxes of contaminants through resource-related ecosystems, and about contaminant effects on resource species as demonstrated in field and laboratory experiments. Other possible management activities include: (1) encouragement of continued efforts to document clearly the localized and general effects of pollution on living resources; (2) continued pressure to identify and use reliable biological indicators of environmental degradation (indicators of choice at present are: unusually high levels of genetic and other anomalies in the earliest life history stages; presence of pollution-associated disease signs, particularly fin erosion and ulcers, in fish; and biochemical/physiological changes); and (3) major efforts to reduce inputs of pollutants clearly demonstrated to be harmful to living resources, from point sources as well as ocean dumping. Such pollution management activities, based on continuous efforts in stock assessment, environmental assessment, and experimental studies, can help to insure that rational decisions will be made about uses and abuses of coastal

  13. Biochemical methane potential (BMP) of artichoke waste: the inoculum effect.

    Science.gov (United States)

    Fabbri, Andrea; Serranti, Silvia; Bonifazi, Giuseppe

    2014-03-01

    The aim of this work was to investigate anaerobic digestibility of artichoke waste resulting from industrial transformation. A series of batch anaerobic digestion tests was performed in order to evaluate the biochemical methane potential of the matrix in respect of the process. A comparison of the different performances of the laboratory-scale reactors operating in mesophilic conditions and utilizing three different values of the inoculum/substrate ratio was carried out. The best performance was achieved with an inoculum/substrate ratio of 2. Artichoke-processing byproducts showed a classical organic waste decomposition behaviour: a fast start-up phase, an acclimation stage, and a final stabilization phase. Following this approach, artichoke waste reached chemical oxygen demand removal of about 90% in 40 days. The high methane yield (average 408.62 mL CH4 gvs (-1) voltatile solids), makes artichoke waste a good product to be utilized in anaerobic digestion plants for biogas production.

  14. Monsoon effect simulation on typhoon rainfall potential - Typhoon Morakot (2009

    Directory of Open Access Journals (Sweden)

    Yi-Ling Chang

    2017-01-01

    Full Text Available A record breaking extreme precipitation event produced 3000 mm day-1 of accumulated rainfall over southern Taiwan in August 2009. The interactions between Typhoon Morakot and the prevailing southwesterly (SW monsoon are the primary mechanism for this heavy precipitation during 5 - 13 August 2009. This extreme precipitation could be produced by the abundant moisture from the SW monsoon associated with the interaction between typhoon and monsoon wind fields, leading to severe property damage. The accurate mapping of extreme precipitation caused from the interaction between a monsoon and typhoon is critical for early warning in Taiwan. This study simulates the heavy rainfall event is based on the Weather Research and Forecast system model (WRF using the three nested domain configuration. Using data assimilation with a virtual meteorological field using the 3D-Var system, such as wind field to alter the SW monsoon strength in the initial condition, the impacts of intensified convergence and water vapor content on the accumulated rainfall are analyzed to quantize the intensification of typhoon rainfall potential. The results showed a positive correlation between the enhanced precipitation and the intensity of low-level wind speed convergence as well as water vapor content. For the Typhoon Morakot case study the rainfall for could attain approximately 2 × 104 mm at 6 hours interval in the southern Taiwan area when 10 × 10-6 s-1 convergence intensified at 850 hPa level around the southern part of the Taiwan Strait. These results suggest that low-level wind speed, convergence and water vapor content play key roles in the typhoon rainfall potential coupled with the SW monsoon.

  15. Effects of captopril on the heart mechanisms and therapeutic potentials

    NARCIS (Netherlands)

    Graeff, Pieter Andries de

    1989-01-01

    This thesis describes the experimental and clinical effects of captopril on the heart. Captopril was the first angiotensin converting enzyme inhibitor for oral administration. This enzyme is responsiblef or the conversion of angiotensin I in angiotensinII , one of the most potent pressor substances

  16. Effects of stimulus duration on gustatory evoked potentials

    DEFF Research Database (Denmark)

    Rotvel, Camilla Arndal; Møller, Stine; Kivisaar, Kätlin

    The objective of the present study was to investigate the effect of tastant stimulus duration on the brain response. The brain response was measured by electroencephalography (EEG) which measures neural processes with high temporal resolution and may therefore complement sensory panel assessments...

  17. The potential protective effects of erythropoietin and estrogen on ...

    African Journals Online (AJOL)

    Noha I. Hussien

    2015-12-30

    Dec 30, 2015 ... Abstract Background: Renal ischemia–reperfusion (RIR) is an important etiopathological mech- anism of acute renal failure (ARF). Erythropoietin (EPO) has been candidate as a nephroprotectant agent. However, its nephroprotective effect when it is accompanied with estrogen has not been stud-.

  18. Effects of Triaxiality, Oblateness and Gravitational Potential from a ...

    Indian Academy of Sciences (India)

    R3BP) in which the more massive primary is triaxial, the less massive primary and infinitesimal body are oblate spheroids, and are encompassed by a belt of homogenous material points. Analytically and numerically, we have studied the effects of ...

  19. Potential Effects of Domestic Energy on the Health of Women ...

    African Journals Online (AJOL)

    Sources of domestic energy in Nigeria include coal; firewood; kerosene; liquefied natural gas (LNG); electricity and sawdust. The gaseous and other chemical emissions by these materials in the course of energy production have been recorded as having adverse effects on the health of the users and other exposed persons ...

  20. The effect of nonlinearity in relativistic nucleon–nucleon potential

    Indian Academy of Sciences (India)

    2014-04-01

    Apr 1, 2014 ... This is because of the high-quality predictive power of NL3 [26] over HS. [11] throughout the periodic table. In addition to the shifting of barrier position and height, the effect of various model parameters cannot be neglected as one can observe from the fifth and seventh columns of table 1. We also study the ...

  1. Evaluation of Potential Effect of Menthol Solution on Oral Hygiene ...

    African Journals Online (AJOL)

    Purpose: To test the effect of menthol extract on the oral hygiene status of dental students of Faculty of. Dentistry ... positive and Gram-negative bacteria [9]. .... animals, which in turn indicates that this substance is well tolerated. Elimination of menthol extract from oral cavity. The volunteers in the study group had mean age.

  2. The effect of cognitive training on evoked potentials in schizophrenia

    Directory of Open Access Journals (Sweden)

    Daniela Kariofillis

    2014-12-01

    The more general visuo-spatial training appears to have a longer-lasting effect on P2 latency than the specific auditory training. Alternatively, there may be specific auditory discrimination deficits in schizophrenia requiring more extensive training for a stable change.

  3. Evaluation of Potential Effect of Menthol Solution on Oral Hygiene ...

    African Journals Online (AJOL)

    Purpose: To test the effect of menthol extract on the oral hygiene status of dental students of Faculty of Dentistry, Al- Mustansiriya University, Baghdad, Iraq. Methods: A solution (18 mg %) of menthol was prepared by dissolving menthol crystals in absolute ethanol. Chlorhexidine (CHX, 0.2 %) and deionized water were used ...

  4. The Potential of Directed Instruction to Teach Effectively Technology Usage

    Science.gov (United States)

    Hosseini, Zahra

    2016-01-01

    Currently, teacher educational systems tend to develop their teachers' knowledge to effectively integrate technology in teaching. Consequently, numerous studies have attempted to describe strategies, models and approaches to develop teachers' knowledge for teaching with technology. However, most teachers are still following their traditional…

  5. Tebufenozide effects on the reproductive potentials of the ...

    African Journals Online (AJOL)

    The Mediterranean flour moth, Ephestia Kuehniella Zeller (Lepidoptera: Pyralidae), is an important pest in stored products worldwide, and is one of the major pests in flour mills in Algeria. Because of environmental consideration, alternative approaches to neurotoxic insecticides, as well as safe, effective, and sound ...

  6. Toxicity potentials and novelty-induced behavior effects of JEDDY ...

    African Journals Online (AJOL)

    Acute administration of JEDDY decoction at the three dose levels (344, 667 and 1334 ìl/kg/30 days, p.o.) also revealed no significant effects on locomotion activities when compared with the control but the ANOVA revealed that there was a significant decrease in grooming activities at the dose of 667 ìl/kg only when ...

  7. Leadership Intelligence: Unlocking the Potential for School Leadership Effectiveness

    Science.gov (United States)

    Gage, Timothy; Smith, Clive

    2016-01-01

    Top performing companies have long used intelligence tests in their selection procedures to predict who the best leaders are. However, no longer are the brightest favoured, or guaranteed success. A post-modern world demands a fresh outlook on leadership. How can school leaders judge their effectiveness? How can school leaders lead intelligently?…

  8. Potential antioxidant and antiapoptotic effects of eplerenone versus ...

    African Journals Online (AJOL)

    Use of proton pump inhibitors as omeprazole in prophylaxis against gastric stress ulcers complicating acute myocardial infarction leads to serious cardiovascular events. Eplerenone is one of the drugs used in treatment of acute myocardial infarction. We have investigated in the current study the possible protective effects of ...

  9. The potential protective effects of erythropoietin and estrogen on ...

    African Journals Online (AJOL)

    Background: Renal ischemia–reperfusion (RIR) is an important etiopathological mechanism of acute renal failure (ARF). Erythropoietin (EPO) has been candidate as a nephroprotectant agent. However, its nephroprotective effect when it is accompanied with estrogen has not been studied in female. Methods: Fifty-six female ...

  10. Potential protective effects of rosemary extract, against aspartame ...

    African Journals Online (AJOL)

    The present study seeks to evaluate the possible protective effects of aqueous rosemary extract against aspartame overdose-induced hepatotoxicity in rats. Three groups of rats were treated orally one time /2 days for twelve weeks: first group was regarded as control, the second group was given aspartame at a dose level of ...

  11. Matter-wave bright solitons in effective bichromatic lattice potentials

    Indian Academy of Sciences (India)

    2013-08-01

    Aug 1, 2013 ... dous momentum due to the possibility to realize different phenomena of nonlinear optics and condensed-matter physics by ... Flexibility of an OL has successfully been used to observe many phenomena such as. Josephson effects .... Thus, we write the trial solution as [18,19] φ(x, t) = A(t)sech. [. (x − x0(t)).

  12. Antidiabetic potentials of Momordica charantia: multiple mechanisms behind the effects.

    Science.gov (United States)

    Chaturvedi, Padmaja

    2012-02-01

    Momordica charantia fruits are used as a vegetable in many countries. From time immemorial, it has also been used for management of diabetes in the Ayurvedic and Chinese systems of medicine. Information regarding the standardization of this vegetable for its usage as an antidiabetic drug is scanty. There are many reports on its effects on glucose and lipid levels in diabetic animals and some in clinical trials. Reports regarding its mechanism of action are limited. So in the present review all the information is considered to produce some concrete findings on the mechanism behind its hypoglycemic and hypolipidemic effects. Studies have shown that M. charantia repairs damaged β-cells, increases insulin levels, and also enhance the sensitivity of insulin. It inhibits the absorption of glucose by inhibiting glucosidase and also suppresses the activity of disaccharidases in the intestine. It stimulates the synthesis and release of thyroid hormones and adiponectin and enhances the activity of AMP-activated protein kinase (AMPK). Effects of M. charantia like transport of glucose in the cells, transport of fatty acids in the mitochondria, modulation of insulin secretion, and elevation of levels of uncoupling proteins in adipose and skeletal muscles are similar to those of AMPK and thyroxine. Therefore it is proposed that effects of M. charantia on carbohydrate and fat metabolism are through thyroxine and AMPK.

  13. Slow high-frequency effects in mechanics: problems, solutions, potentials

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    2005-01-01

    and compared: The Method of Direct Separation of Motions, the Method of Averaging, and the Method of Multiple Scales. The tutorial concludes by suggesting that more vibration experts, researchers and students should know about HFE effects, for the benefit not only of general vibration troubleshooting, but also...

  14. Isotope geochemistry reveals ontogeny of dispersal and exchange between main-river and tributary habitats in smallmouth bass Micropterus dolomieu.

    Science.gov (United States)

    Humston, R; Doss, S S; Wass, C; Hollenbeck, C; Thorrold, S R; Smith, S; Bataille, C P

    2017-02-01

    Radiogenic strontium isotope ratios ( 87 Sr: 86 Sr) in otoliths were compared with isotope ratios predicted from models and observed in water sampling to reconstruct the movement histories of smallmouth bass Micropterus dolomieu between main-river and adjacent tributary habitats. A mechanistic model incorporating isotope geochemistry, weathering processes and basin accumulation reasonably predicted observed river 87 Sr: 86 Sr across the study area and provided the foundations for experimental design and inferring fish provenance. Exchange between rivers occurred frequently, with nearly half (48%) of the 209 individuals displaying changes in otolith 87 Sr: 86 Sr reflecting movement between isotopically distinct rivers. The majority of between-river movements occurred in the first year and often within the first few months of life. Although more individuals were observed moving from the main river into tributaries, this pattern did not necessarily reflect asymmetry in exchange. Several individuals made multiple movements between rivers over their lifetimes; no patterns were found, however, that suggest seasonal or migratory movement. The main-river sport fishery is strongly supported by recruitment from tributary spawning, as 26% of stock size individuals in the main river were spawned in tributaries. The prevailing pattern of early juvenile dispersal documented in this study has not been observed previously for this species and suggests that the process of establishing seasonal home-range areas occurs up to 2 years earlier than originally hypothesized. Extensive exchange between rivers would have substantial implications for management of M. dolomieu populations in river-tributary networks. © 2016 The Fisheries Society of the British Isles.

  15. Effective Interatomic Potentials Based on The First-Principles Material Database

    OpenAIRE

    Yamamoto, T; Ohnishi, S; Chen, Y; Iwata, S

    2009-01-01

    Effective interatomic potentials are frequently utilized for large-scale simulations of materials. In this work, we generate an effective interatomic potential, with Niobium as an example, using the force-matching method derived from a material database which is created by the first-principle molecular dynamics. It is found that the potentials constructed in the present work are more transferable than other existing potential models. We further discuss how the first-principles material databa...

  16. EFFECT OF SOIL WATER POTENTIAL ON TRANSPIRATION RATE IN CUCUMBER PLANTS

    OpenAIRE

    Cho, Tosio; Eguchi, Hiromi; Kuroda, Masaharu; Tanaka, Akira; Koutaki, Masahiro; Ng, Ah Lek; Matsui, Tsuyoshi

    1985-01-01

    In an attempt to examine the effect of soil water potential (pF) on transpiration rate, leaf temperature of cucumber plants was measured under various conditions of soil water potential, and transpiration rate was calculated from heat balance of the leaf. Transpiration rate decreased with reduction in soil water potential; transpiration rate dropped at soil water potentials lower than pF 3.0. This fact suggests that the reduction in soil water potential restricts water uptake in roots and cau...

  17. Potential immunomodulatory effects of latent toxoplasmosis in humans

    Directory of Open Access Journals (Sweden)

    Stříž Ilja

    2011-10-01

    Full Text Available Abstract Background About 30% of the population worldwide are infected with the protozoan parasite Toxoplasma gondii. Latent toxoplasmosis has many specific behavioral and physiological effects on the human organism. Modified reactivity of the immune system has been suggested to play a key role in many of these effects. For example, the immunosuppression hypothesis explains the higher probability of the birth of male offspring observed in Toxoplasma-positive humans and mice by the protection of the (more immunogenic male embryos against abortion. Methods Here we searched for indices of immunosuppression in Toxoplasma-positive subjects by comparing clinical records of immunology outpatients. Results Our cohort study showed that the male patients with latent toxoplasmosis had decreased and the Toxoplasma-positive women had increased leukocyte, NK-cell and monocyte counts in comparison with controls. The B-cell counts were reduced in both Toxoplasma-positive men and women. The difference between Toxoplasma-positive and Toxoplasma-negative subjects diminished with the decline of the specific Toxoplasma antibody titre (a proxy for the length of infection, which is consistent with the observed decreasing strength of the effect of latent toxoplasmosis on human reproduction. The prevalence of toxoplasmosis in 128 male patients was unusually low (10.9% which contrasted with normal prevalence in 312 female patients (23.7% and in general population Prague (20-30%. Conclusions Latent toxoplasmosis has immunomodulatory effects in human and probably protects men against some classes of immunopathological diseases. The main limitation of the present study was the absence of the data on the immunoreactivity of immune cells subpopulations. Therefore further studies are needed to search for indices of immunosuppression in human using more specific markers.

  18. Potential effects of mercury on threatened California black rails

    Science.gov (United States)

    Tsao, Danika C.; Miles, A. Keith; Takekawa, John Y.; Woo, Isa

    2009-01-01

    San Francisco Bay (SFB) estuary sediments contain high levels of mercury (Hg), and tidal marsh resident species may be vulnerable to Hg contamination. We examined Hg concentrations in California black rails, a threatened waterbird species that inhabits SFB tidal salt marshes. We captured 127 black rails during the prebreeding and postbreeding seasons and examined the influence of site, sex, and year on Hg, methylmercury (MeHg), and also selenium (Se) concentrations in feathers and blood. Feather Hg concentrations averaged 6.94 ??g/g dry weight (dw) and MeHg and Se concentrations in blood averaged 0.38 and 0.42 ??g/g wet weight (ww). We used Akaike's information criterion model selection process to evaluate the importance of year, site, sex, and age on patterns of MeHg concentrations; sex and year were the most important of these factors. Feather Hg concentrations (dw) were higher in males (8.22 ??g/g) than females (6.63 ??g/g) and higher in adult birds (7.36 ??g/g) than in hatch-year birds (4.61 ??g/g). A substantial portion of SFB black rail populations may be at risk of reproductive effects due to MeHg contamination, as 32-78% of feathers and toxicological effects would further elucidate the effects of MeHg contamination on black rail populations in SFB. ?? 2008 Springer Science+Business Media, LLC.

  19. Occurrence and Transport of Diazinon in the Sacramento River and Selected Tributaries, California, during Two Winter Storms, January?February 2001

    Science.gov (United States)

    Dileanis, Peter D.; Brown, David L.; Knifong, Donna L.; Saleh, Dina

    2003-01-01

    Diazinon, an organophosphate insecticide, is applied as an orchard dormant spray in the Sacramento Valley during the winter months when the area receives most of its annual rainfall. During winter rainstorms that frequently follow dormant spray applications, some of the applied pesticide is transported in storm runoff to the Sacramento River and its tributaries. Diazinon is also used to control insect pests on residential and commercial properties in urban areas and is frequently detected in urban storm runoff draining into the Sacramento River system. Between January 24 and February 14, 2001, diazinon concentrations and loads were measured in the Sacramento River and selected tributaries during two winter storms that occurred after dormant spray applications were made to orchards in the Sacramento Valley. Water samples were collected at 21 sites that represented agricultural and urban inputs on a variety of scales, from small tributaries and drains representing local land use to main-stem river sites representing regional effects. Concentrations of diazinon ranged from below laboratory reporting levels to 1,380 nanograms per liter (ng/L), with a median of 55 ng/L during the first monitored storm and 26 ng/L during the second. The highest concentrations were observed in small channels draining predominantly agricultural land. About 26,000 pounds of diazinon were reported applied to agricultural land in the study area just before and during the monitoring period. About 0.2 percent of the applied insecticide appeared to be transported to the lower Sacramento River during that period. The source of about one third of the total load measured in the lower Sacramento River appears to be in the portion of the drainage basin upstream of the city of Colusa. About 12 percent of the diazinon load in the lower Sacramento River was transported from the Feather River Basin, which drains much of the mountainous eastern portions of the Sacramento River Basin. Diazinon use in the

  20. Contracting of energy services in Switzerland. Development, effects, market potentials

    International Nuclear Information System (INIS)

    Muggli, C.; Baumgartner, W.; Kohn, L.

    1999-06-01

    The authors of this detailed report first define the contracting of energy services, this new reality of the market place, and analyse its current status in Switzerland. Contracting is mainly to be understood as the delegation of certain energy-related services by a company. The total investment for the operated energy systems considered by the study is about 120 millions USD, with an installed power of 160 MW. This market is highly unhomogeneous and is the answer to various goals. Globally, it brings a more efficient use of energy, including a more frequent involvement of renewable energy sources, along with a lower risk and significant advantages for all contractors. That is the reason for the energy policy authority to recommend contracting. The report goes on with the analysis of the factors leading the chief executives to consider contracting of energy services, or on the contrary to exclude it. The authors estimate the realistic potential market for contracting in Switzerland to 650 millions USD for the period 1999-2004. They conclude by giving recommendations which should result in an acceleration of the contracting's development on the market place

  1. Areal distribution and concentration of contaminants of concern in surficial streambed and lakebed sediments, Lake St. Clair and tributaries, Michigan, 1990-2003

    Science.gov (United States)

    Rachol, Cynthia M.; Button, Daniel T.

    2006-01-01

    As part of the Lake St. Clair Regional Monitoring Project, the U.S. Geological Survey evaluated data collected from surficial streambed and lakebed sediments in the Lake Erie-Lake St. Clair drainages. This study incorporates data collected from 1990 through 2003 and focuses primarily on the U.S. part of the Lake St. Clair Basin, including Lake St. Clair, the St. Clair River, and tributaries to Lake St. Clair. Comparable data from the Canadian part of the study area are included where available. The data are compiled into 4 chemical classes and consist of 21 compounds. The data are compared to effects-based sediment-quality guidelines, where the Threshold Effect Level and Lowest Effect Level represent concentrations below which adverse effects on biota are not expected and the Probable Effect Level and Severe Effect Level represent concentrations above which adverse effects on biota are expected to be frequent.Maps in the report show the spatial distribution of the sampling locations and illustrate the concentrations relative to the selected sediment-quality guidelines. These maps indicate that sediment samples from certain areas routinely had contaminant concentrations greater than the Threshold Effect Concentration or Lowest Effect Level. These locations are the upper reach of the St. Clair River, the main stem and mouth of the Clinton River, Big Beaver Creek, Red Run, and Paint Creek. Maps also indicated areas that routinely contained sediment contaminant concentrations that were greater than the Probable Effect Concentration or Severe Effect Level. These locations include the upper reach of the St. Clair River, the main stem and mouth of the Clinton River, Red Run, within direct tributaries along Lake St. Clair and in marinas within the lake, and within the Clinton River headwaters in Oakland County.Although most samples collected within Lake St. Clair were from sites adjacent to the mouths of its tributaries, samples analyzed for trace-element concentrations

  2. Potentiation of Anticancer Drugs: Effects of Pentoxifylline on Neoplastic Cells

    Directory of Open Access Journals (Sweden)

    Miroslav Barancik

    2011-12-01

    Full Text Available The drug efflux activity of P-glycoprotein (P-gp, a product of the mdr1 gene, ABCB1 member of ABC transporter family represents a mechanism by which tumor cells escape death induced by chemotherapeutics. In this study, we investigated the mechanisms involved in the effects of pentoxifylline (PTX on P-gp-mediated multidrug resistance (MDR in mouse leukemia L1210/VCR cells. Parental sensitive mouse leukemia cells L1210, and multidrug-resistant cells, L1210/VCR, which are characterized by the overexpression of P-gp, were used as experimental models. The cells were exposed to 100 μmol/L PTX in the presence or absence of 1.2 μmol/L vincristine (VCR. Western blot analysis indicated a downregulation of P-gp protein expression when multidrug-resistant L1210/VCR cells were exposed to PTX. The effects of PTX on the sensitization of L1210/VCR cells to VCR correlate with the stimulation of apoptosis detected by Annexin V/propidium iodide apoptosis necrosis kit and proteolytic activation of both caspase-3 and caspase-9 monitored by Western blot analysis. Higher release of matrix metalloproteinases (MMPs, especially MMP-2, which could be attenuated by PTX, was found in L1210/VCR than in L1210 cells by gelatin zymography in electrophoretic gel. Exposure of resistant cells to PTX increased the content of phosphorylated Akt kinase. In contrast, the presence of VCR eliminated the effects of PTX on Akt kinase phosphorylation. Taken together, we conclude that PTX induces the sensitization of multidrug-resistant cells to VCR via downregulation of P-gp, stimulation of apoptosis and reduction of MMPs released from drug-resistant L1210/VCR cells. These facts bring new insights into the mechanisms of PTX action on cancer cells.

  3. Effects of experimental income on demand for potentially real cigarettes.

    Science.gov (United States)

    Koffarnus, Mikhail N; Wilson, Arlington George; Bickel, Warren K

    2015-03-01

    Cigarette demand, or the change in cigarette consumption as a function of price, is a measure of reinforcement that is associated with level of tobacco dependence and other clinically relevant measures, but the effects of experimentally controlled income on real-world cigarette consumption have not been examined. In this study, income available for cigarette purchases was manipulated to assess the effect on cigarette demand. Tobacco-dependent cigarette smokers (n = 15) who smoked 10-40 cigarettes per day completed a series of cigarette purchasing tasks under a variety of income conditions meant to mimic different weekly cigarette budgets: $280, approximately $127, $70, or approximately $32 per week. Prices of $0.12, $0.25, $0.50, and $1.00 per cigarette were assessed in each income condition. Participants were instructed to purchase as many cigarettes as they would like for the next week and to only consume cigarettes purchased in the context of the study. One price in 1 income condition was randomly chosen to be "real," and the cigarettes and the excess money in the budget for that condition were given to the participant. Results indicate that demand elasticity was negatively correlated with income. Demand intensity (consumption at low prices) was unrelated to income condition and remained high across incomes. These results indicate that the amount of income that is available for cigarette purchases has a large effect on cigarette consumption, but only at high prices. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Melatonin intake and potential chronobiological effects on human health.

    Science.gov (United States)

    Gomes Domingos, Ana Luiza; Hermsdorff, Helen Hermana Miranda; Bressan, Josefina

    2017-08-11

    Melatonin is an indolamine with a recognized chronobiotic role. In turn, the supplementation of melatonin through capsules has been shown to be efficient in the modulation of inflammatory markers, oxidative stress, as well as in the control of hypertension and metabolic syndrome. However, the science of nutrition is interested in the study of the food sources of this hormone and its possible therapeutic effects. Thus, this review aimed to identify and present scientific papers that quantified melatonin in foods and evaluated its application in intervention studies. In total, 278 studies were found, of which 17 were included in this review. The results show that meats, fish, eggs, cereals, tubers, oilseeds, mushrooms, fruits, vegetables, alcoholic and non-alcoholic beverages and dairy products had some items analyzed for their melatonin concentrations. The concentrations reported presented considerable amplitude among different foods and even within the same species, possibly due to differences in cultivation and different hormonal dosing techniques. Also, different concentrations of melatonin can be presented for the same food when submitted to processes such as cooking, roasting or fermentation. The intervention studies presented positive results regarding the consumption of foods rich in melatonin and clinical-metabolic indicators. However, in order to guide nutritional behavior, it is necessary to consult a composition table that makes melatonin concentrations available and considers the processes involved in the preparation of the food. With this table, it will be possible to analyze the real effect of habitual consumption of melatonin from food on health.

  5. Late effects of breast cancer treatment and potentials for rehabilitation

    International Nuclear Information System (INIS)

    Ewertz, Marianne; Bonde Jensen, Anders

    2011-01-01

    Background. Breast cancer is the most frequent malignant disease among women world wide. Survival has been improving leading to an increasing number of breast cancer survivors, in the US estimated to about 2.6 million. Material and methods. The literature was reviewed with focus on data from the Nordic countries. Results. Local therapies such as breast cancer surgery and radiotherapy may cause persistent pain in the breast area, arm, and shoulder reported by 30-50% of patients after three to five years, lymphedema in 15-25% of patients, and restrictions of arm and shoulder movement in 35%. Physiotherapy is the standard treatment for the latter while no pain intervention trials have been published. Chemotherapy may cause infertility and premature menopause, resulting in vasomotor symptoms, sexual dysfunction, and osteoporosis, which are similar to the side effects of endocrine treatment in postmenopausal women. Awareness of cardiotoxicity is needed since anthracyclines, trastuzumab, and radiotherapy can damage the heart. Breast cancer survivors have an increased risk of a major depression and far from all receive adequate anti-depressive treatment. Other psychological symptoms include fear of recurrence, sleep disturbances, cognitive problems, fatigue, and sexual problems. Discussion. To improve rehabilitation, specific goals have to be formulated into national guidelines and high priority directed towards research into developing and testing new interventions for alleviating symptoms and side effects experienced by breast cancer survivors

  6. Late effects of breast cancer treatment and potentials for rehabilitation

    Energy Technology Data Exchange (ETDEWEB)

    Ewertz, Marianne (Dept. of Oncology, Odense Univ. Hospital, Odense (Denmark)); Bonde Jensen, Anders (Inst. of Clinical Research, Univ. of Southern Denmark (Denmark))

    2011-02-15

    Background. Breast cancer is the most frequent malignant disease among women world wide. Survival has been improving leading to an increasing number of breast cancer survivors, in the US estimated to about 2.6 million. Material and methods. The literature was reviewed with focus on data from the Nordic countries. Results. Local therapies such as breast cancer surgery and radiotherapy may cause persistent pain in the breast area, arm, and shoulder reported by 30-50% of patients after three to five years, lymphedema in 15-25% of patients, and restrictions of arm and shoulder movement in 35%. Physiotherapy is the standard treatment for the latter while no pain intervention trials have been published. Chemotherapy may cause infertility and premature menopause, resulting in vasomotor symptoms, sexual dysfunction, and osteoporosis, which are similar to the side effects of endocrine treatment in postmenopausal women. Awareness of cardiotoxicity is needed since anthracyclines, trastuzumab, and radiotherapy can damage the heart. Breast cancer survivors have an increased risk of a major depression and far from all receive adequate anti-depressive treatment. Other psychological symptoms include fear of recurrence, sleep disturbances, cognitive problems, fatigue, and sexual problems. Discussion. To improve rehabilitation, specific goals have to be formulated into national guidelines and high priority directed towards research into developing and testing new interventions for alleviating symptoms and side effects experienced by breast cancer survivors

  7. POTENTIAL PATHOPHYSIOLOGICAL MECHANISMS OF ULTRAFINE PARTICLE TOXIC EFFECTS IN HUMANS

    Directory of Open Access Journals (Sweden)

    JASMINA JOVIĆ-STOŠIĆ

    2008-03-01

    Full Text Available Epidemiological and clinical studies suggested the association of the particulate matter ambient air pollution and the increased morbidity and mortality, mainly from respiratory and cardiovascular diseases. The size of particles has great influence on their toxicity, because it determines the site in the respiratory tract where they deposit. The most well established theory explaining the mechanisms behind the increased toxicity of ultrafine particles (UFP, < 0.1 µm is that it has to do with the increased surface area and/or the combination with the increased number of particles. Biological effects of UFP are also determined by their shape and chemical composition, so it is not possible to estimate their toxicity in a general way. General hypothesis suggested that exposure to inhaled particles induces pulmonary alveolar inflammation as a basic pathophysiological event, triggering release of various proinflammatory cytokines. Chronic inflammation is a very important underlying mechanism in the genesis of atherosclerosis and cardiovascular diseases. UFP can freely move through the circulation, but their effects on the secondary organs are not known yet, so more studies on recognizing toxicological endpoints of UFP are needed. Determination of UFP toxicity and the estimation of their internal and biologically active dose are necessary for the evidence based conclusions connecting air pollution by UFP and human diseases.

  8. Mitigating the Goldilocks effect: the effects of different substrate models on track formation potential.

    Science.gov (United States)

    Falkingham, Peter L; Hage, Julian; Bäker, Martin

    2014-11-01

    In ichnology, the Goldilocks effect describes a scenario in which a substrate must be 'just right' in order for tracks to form-too soft, the animal will be unable to traverse the area, and too firm, the substrate will not deform. Any given substrate can therefore only preserve a range of tracks from those animals which exert an underfoot pressure at approximately the yield strength of the sediment. However, rarely are substrates vertically homogeneous for any great depth, varying either due to heterogeneity across sediment layers, or from mechanical behaviour such as strain hardening. Here, we explore the specificity of the Goldilocks effect in a number of virtual substrates simulated using finite-element analysis. We find that the inclusion of strain hardening into the model increases the potential range of trackmaker sizes somewhat, compared with a simple elastic-perfectly plastic model. The simulation of a vertically heterogeneous, strain hardening substrate showed a much larger range of potential trackmakers than strain hardening alone. We therefore show that the Goldilocks effect is lessened to varying degrees by the inclusion of more realistic soil parameters, though there still remains an upper and lower limit to the size of trackmaker able to traverse the area while leaving footprints.

  9. A potential calcium antagonist and its antihypertensive effects.

    Science.gov (United States)

    Zhang, Yan; Cao, YanJun; Wang, QunLi; Zheng, Lei; Zhang, Jie; He, LangChong

    2011-10-01

    Imperatorin (Imp) as a hypotensive active ingredient, its hypotensive effect was evaluated in the SHRs, its calcium antagonism and affinity to L-type calcium channel was also confirmed. The results showed that the blood pressure was decreased in the SHRs treated with Imp, the aortic ring was relaxed with Imp, L-type calcium channel currents and intracellular calcium free ion rise was nearly disappeared when adding Imp. In addition, Imp displayed a chromatographic peak similar to nitrendipine and verapamil by the cell membrane chromatography, same results from protein-drug docking approaches. Hence, Imp target the L-type calcium channel, and may be used as a novel antihypertensive drug. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Potential Effects of Disruptive Political Trends in International Tourism Market

    Directory of Open Access Journals (Sweden)

    Ali Öztüren

    2017-05-01

    Full Text Available The purpose of this paper is to discuss the prospective effects of the latest political incidences on the international tourism market. In this context, the arguments are based on the implications of the USA elections and the Brexit. The methodology of this paper comprises the discussion of the debates related to the recent political experiences. International tourism activities cannot be isolated from the political environment. It is clear that the new political incidences will require novel insights and strategies in conducting international tourism business globally. This paper provides a viewpoint of the today’s political scenarios that will certainly affect the international tourism market. It can be used to comprehend insights that can be used to plan the tourism futures.

  11. Plant effects on soil denitrification - a review of potential mechanisms

    Science.gov (United States)

    Malique, Francois; Butterbach-Bahl, Klaus; Dannenmann, Michael

    2017-04-01

    Denitrification is a microbial process occurring in soils, both producing and consuming the potent greenhouse gas nitrous oxide (NO), competing for nitrate with plants and hydrological leaching pathways, removing nutrients and reactive nitrogen from the biosphere, and closing the global nitrogen cycle. Despite its obvious importance, denitrification remained among the least well quantified biogeochemical processes in soils. This is due to enormous methodological difficulties involved in the direct quantification of soil microbial denitrification rates (mainly with regard to the terminal product N2) and the denitrification nitrogen gas product ratios (NO:N2O:N2), Plants may affect denitrification through a myriad of mechanisms such as e.g., competition for nitrate and water, through oxygen consumption, by regulating litter quality and changing soil pH, and via the exudation of labile carbon or secondary plant compounds involved in shaping the rhizospheric microbial community. However, plant effects on denitrification so far hardly were quantified so that the actual extent of plant control on denitrification is largely unknown. Here, we summarize the current knowledge on mechanisms how plants can affect denitrification rates and N gas product ratios in soils at temporal scales from hours to days and years. We review earlier research to quantify plant effects on denitrification as well as critically discuss the limited methods currently available to quantify plant-soil-denitrifier interactions. Finally, we provide pointers to use plants as tools to manage denitrification, e.g. to improve N use efficiency in agricultural ecosystems and to minimize soil nitrous oxide emissions.

  12. Year-round presence of neonicotinoid insecticides in tributaries to the Great Lakes, USA.

    Science.gov (United States)

    Hladik, Michelle L; Corsi, Steven R; Kolpin, Dana W; Baldwin, Austin K; Blackwell, Brett R; Cavallin, Jenna E

    2018-04-01

    To better characterize the transport of neonicotinoid insecticides to the world's largest freshwater ecosystem, monthly samples (October 2015-September 2016) were collected from 10 major tributaries to the Great Lakes, USA. For the monthly tributary samples, neonicotinoids were detected in every month sampled and five of the six target neonicotinoids were detected. At least one neonicotinoid was detected in 74% of the monthly samples with up to three neonicotinoids detected in an individual sample (10% of all samples). The most frequently detected neonicotinoid was imidacloprid (53%), followed by clothianidin (44%), thiamethoxam (22%), acetamiprid (2%), and dinotefuran (1%). Thiacloprid was not detected in any samples. The maximum concentration for an individual neonicotinoid was 230 ng L -1 and the maximum total neonicotinoids in an individual sample was 400 ng L -1 . The median detected individual neonicotinoid concentrations ranged from non-detect to 10 ng L -1 . The detections of clothianidin and thiamethoxam significantly increased as the percent of cultivated crops in the basins increased (ρ = 0.73, P = .01; ρ = 0.66, P = .04, respectively). In contrast, imidacloprid detections significantly increased as the percent of the urbanization in the basins increased (ρ = 0.66, P = .03). Neonicotinoid concentrations generally increased in spring through summer coinciding with the planting of neonicotinoid-treated seeds and broadcast applications of neonicotinoids. More spatially intensive samples were collected in an agriculturally dominated basin (8 sites along the Maumee River, Ohio) twice during the spring, 2016 planting season to provide further information on neonicotinoid inputs to the Great Lakes. Three neonicotinoids were ubiquitously detected (clothianidin, imidacloprid, thiamethoxam) in all water samples collected within this basin. Maximum individual neonicotinoid concentrations was 330 ng L -1 and maximum total

  13. Year-round presence of neonicotinoid insecticides in tributaries to the Great Lakes, USA

    Science.gov (United States)

    Hladik, Michelle; Corsi, Steven; Kolpin, Dana W.; Baldwin, Austin K.; Blackwell, Brett R.; Cavallin, Jenna E.

    2018-01-01

    To better characterize the transport of neonicotinoid insecticides to the world's largest freshwater ecosystem, monthly samples (October 2015–September 2016) were collected from 10 major tributaries to the Great Lakes, USA. For the monthly tributary samples, neonicotinoids were detected in every month sampled and five of the six target neonicotinoids were detected. At least one neonicotinoid was detected in 74% of the monthly samples with up to three neonicotinoids detected in an individual sample (10% of all samples). The most frequently detected neonicotinoid was imidacloprid (53%), followed by clothianidin (44%), thiamethoxam (22%), acetamiprid (2%), and dinotefuran (1%). Thiacloprid was not detected in any samples. The maximum concentration for an individual neonicotinoid was 230 ng L−1 and the maximum total neonicotinoids in an individual sample was 400 ng L−1. The median detected individual neonicotinoid concentrations ranged from non-detect to 10 ng L−1. The detections of clothianidin and thiamethoxam significantly increased as the percent of cultivated crops in the basins increased (ρ = 0.73, P = .01; ρ = 0.66, P = .04, respectively). In contrast, imidacloprid detections significantly increased as the percent of the urbanization in the basins increased (ρ = 0.66, P = .03). Neonicotinoid concentrations generally increased in spring through summer coinciding with the planting of neonicotinoid-treated seeds and broadcast applications of neonicotinoids. More spatially intensive samples were collected in an agriculturally dominated basin (8 sites along the Maumee River, Ohio) twice during the spring, 2016 planting season to provide further information on neonicotinoid inputs to the Great Lakes. Three neonicotinoids were ubiquitously detected (clothianidin, imidacloprid, thiamethoxam) in all water samples collected within this basin. Maximum individual neonicotinoid concentrations was 330 ng L−1

  14. Evaluating sediment transport in flood-driven ephemeral tributaries using direct and acoustic methods.

    Science.gov (United States)

    Stark, K.

    2017-12-01

    One common source of uncertainty in sediment transport modeling of large semi-arid rivers is sediment influx delivered by ephemeral, flood-driven tributaries. Large variations in sediment delivery are associated with these regimes due to the highly variable nature of flows within them. While there are many sediment transport equations, they are typically developed for perennial streams and can be inaccurate for ephemeral channels. Discrete, manual sampling is labor intensive and requires personnel to be on site during flooding. In addition, flooding within these tributaries typically last on the order of hours, making it difficult to be present during an event. To better understand these regimes, automated systems are needed to continuously sample bedload and suspended load. In preparation for the pending installation of an automated site on the Arroyo de los Piños in New Mexico, manual sediment and flow samples have been collected over the summer monsoon season of 2017, in spite of the logistical challenges. These data include suspended and bedload sediment samples at the basin outlet, and stage and precipitation data from throughout the basin. Data indicate a complex system; flow is generated primarily in areas of exposed bedrock in the center and higher elevations of the watershed. Bedload samples show a large coarse-grained fraction, with 50% >2 mm and 25% >6 mm, which is compatible with acoustic measuring techniques. These data will be used to inform future site operations, which will combine direct sediment measurement from Reid-type slot samplers and non-invasive acoustic measuring methods. Bedload will be indirectly monitored using pipe-style microphones, plate-style geophones, channel hydrophones, and seismometers. These instruments record vibrations and acoustic signals from bedload impacts and movement. Indirect methods for measuring of bedload have never been extensively evaluated in ephemeral channels in the southwest United States. Once calibrated

  15. Tumor prevalence and biomarkers of genotoxicity in brown bullhead (Ameiurus nebulosus) in Chesapeake Bay tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Pinkney, Alfred E., E-mail: Fred_Pinkney@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Harshbarger, John C., E-mail: jcharshbarger@verizon.net [Department of Pathology, George Washington University Medical Center, 2300 I Street, NW, Washington, DC 20037 (United States); Karouna-Renier, Natalie K., E-mail: nkarouna@usgs.gov [U.S. Geological Survey, Patuxent Wildlife Research Center, BARC, Bldg. 308, Beltsville, MD 20705 (United States); Jenko, Kathryn [U.S. Geological Survey, Patuxent Wildlife Research Center, BARC, Bldg. 308, Beltsville, MD 20705 (United States); Balk, Lennart, E-mail: lennart.balk@itm.su.se [Department of Applied Environmental Science (ITM), Stockholm University SE-106 91, Stockholm (Sweden); Skarphe Latin-Small-Letter-Eth insdottir, Halldora; Liewenborg, Birgitta [Department of Applied Environmental Science (ITM), Stockholm University SE-106 91, Stockholm (Sweden); Rutter, Michael A., E-mail: mar36@psu.edu [Department of Mathematics, Penn State Erie, The Behrend College, 5091 Station Road, Erie, PA 16563 (United States)

    2011-12-01

    We surveyed four Chesapeake Bay tributaries for skin and liver tumors in brown bullhead (Ameiurus nebulosus). We focused on the South River, where the highest skin tumor prevalence (53%) in the Bay watershed had been reported. The objectives were to 1) compare tumor prevalence with nearby rivers (Severn and Rhode) and a more remote river (Choptank); 2) investigate associations between tumor prevalence and polynuclear aromatic hydrocarbons (PAHs) and alkylating agents; and 3) statistically analyze Chesapeake Bay bullhead tumor data from 1992 through 2008. All four South River collections exhibited high skin tumor prevalence (19% to 58%), whereas skin tumor prevalence was 2%, 10%, and 52% in the three Severn collections; 0% and 2% in the Choptank collections; and 5.6% in the Rhode collection. Liver tumor prevalence was 0% to 6% in all but one South River collection (20%) and 0% to 6% in the three other rivers. In a subset of samples, PAH-like biliary metabolites and {sup 32}P-DNA adducts were used as biomarkers of exposure and response to polycyclic aromatic compounds (PACs). Adducts from alkylating agents were detected as O6-methyl-2 Prime -deoxyguanosine (O6Me-dG) and O6-ethyl-2 Prime -deoxyguanosine (O6Et-dG) modified DNA. Bullheads from the contaminated Anacostia River were used as a positive control for DNA adducts. {sup 32}P-DNA adduct concentrations were significantly higher in Anacostia bullhead livers compared with the other rivers. We identified alkyl DNA adducts in bullhead livers from the South and Anacostia, but not the Choptank. Neither the PAH-like bile metabolite data, sediment PAH data, nor the DNA adduct data suggest an association between liver or skin tumor prevalence and exposure to PACs or alkylating agents in the South, Choptank, Severn, or Rhode rivers. Logistic regression analysis of the Chesapeake Bay database revealed that sex and length were significant covariates for liver tumors and length was a significant covariate for skin tumors

  16. Synthetic organic agrochemicals in the lower Mississippi River and its major tributaries: Distribution, transport and fate

    Science.gov (United States)

    Pereira, W.E.; Rostad, C.E.; Leiker, T.J.; ,

    1992-01-01

    The Mississippi River and its major tributaries transport herbicides and their degradation products from agricultural areas in the mid-western U.S.A. These compounds include atrazine and its degradation products (desethyl- and desisopropylatrazine), simazine, cyanazine, metolachlor, and alachlor and its degradation products (2-chloro-2',6'-diethylacetanilide, 2-hydroxy-2',6'-diethylacetanilide and 2,6-diethylaniline). These compounds were identified and confirmed by gas chromatography-ion trap mass spectrometry. Loads of these compounds were determined during five sampling trips in 1987-1989. Stream loads of these compounds indicated that atrazine and metolachlor were relatively conservative in downstream transport. Alachlor and its degradation products were generated from point and non-point sources. Seasonal variations and hydrologic conditions controlled the loads of these compounds in the Mississippi River. Cross-channel mixing was slow downstream from major river confluences, possibly requiring several hundred kilometers of downriver transit for completion. The annual transport of these compounds into the Gulf of Mexico was estimated to be < 2% of the annual application of each herbicide in the Midwest.The Mississippi River and its major tributaries transport herbicides and their degradation products from agricultural areas in the mid-western U.S.A. These compounds include atrazine and its degradation products (desethyl- and desisopropylatrazine), simazine, cyanazine, metolachlor, and alachlor and its degradation products (2-chloro-2???,6???-diethylacetanilide, 2-hydroxy-2???,6???-diethylacetanilide and 2,6-diethylaniline). These compounds were identified and confirmed by gas chromatography-ion trap mass spectrometry. Loads of these compounds were determined during five sampling trips in 1987-1989. Stream loads of these compounds indicated that atrazine and metolachlor were relatively conservative in downstream transport. Alachlor and its degradation products

  17. Olive Oil and its Potential Effects on Alzheimer's Disease

    Science.gov (United States)

    Antony, Shan; Zhang, G. P.

    Alzheimer's disease is a neuro-degenerative brain disease that is responsible for affecting the lives of hundreds of thousands of people every year. There has been no evidence to suggest a cure for the disease and the only existing treatments have very low rates of success in trial patients. This is largely due to the fact that the brain is one of the most undiscovered parts of the human body. Brain chemistry is highly complex and responds to its environment in random and radical ways. My research includes testing the reactionary outcomes of combining compounds of olive oil with the 20 basic amino acids. Regions around the world with olive oil based diets show a direct correlation to lower rates of Alzheimer's. Testing few compounds of olive oil with chemicals already found in the brain may yield to a better understanding as to why that is. I took the compounds tyrosol, hydroxytyrosol, and oleocanthal, and combined them with the 20 basic amino acids and calculated the total energy of the new molecule. The molecules produced with acceptably low energy values will be the center of further research. These molecules could lead to truly understanding olive oil's effect on the brain, and ultimately, the cure or prevention of Alzheimer's disease.

  18. Potential exposures and health effects from spent fuel transportation

    International Nuclear Information System (INIS)

    Rogers, V.C.; Sandquist, G.M.; Sutherland, A.A.

    1987-01-01

    The radiation exposures and consequent health effects associated with normal operations and postulated accidents during transportation of spent fuel have been analyzed and evaluated and the results have been summarized in the Final Environmental Assessments issued by DOE. For normal, accident-free transport of spent fuel, radiation exposures arise from both gamma and neutron sources within the spent fuel cask. The neutrons result from the spontaneous fission of transuranic nuclides in the spent fuel. The neutron dose flux component was modeled using DISNEL, a generalized, one-dimensional, multi-energy group neutronics code. Computer program PATHRAE-T was then developed from the EPA code PATHRAE and was employed to determine the total, combined dose field, including both ground and sky scatter of neutrons and gamma photons for any position around a truck or rail spent fuel cask. Four activity classes, viz., caravan, traffic obstruction, resident and pedestrian proximity, and servicing of the cask transport vehicle were reviewed for maximum individual exposure assessments. Projected doses for typical activities under maximum exposure conditions were 6 mrem or less per event. A spent fuel rail cask containing up to 14 PWR spent fuel assemblies could conceivably be involved in a variety of rail related transportation accidents. PATHRAE-T was used to estimate doses from rail cask accidents involving the release of radioactive nuclides although a release from such accidents is highly unlikely. The maximum individual exposure, primarily due to inhalation, is about 10 rem and occurs about 70 meters downwind

  19. Potential effects of invasive Pterois volitans in coral reefs

    Directory of Open Access Journals (Sweden)

    Banamali Maji

    2016-01-01

    Full Text Available The invasion of predatory lionfish (Pterois volitans represents a major threat to the western Atlantic coral reef ecosystems. The proliferation of venomous, fast reproducing and aggressive P. volitans in coral reefs causes severe declines in the abundance and diversity of reef herbivores. There is also widespread cannibalism amongst P. volitans populations. A mathematical model is proposed to study the effects of predation on the biomass of herbivorous reef fishes by considering two life stages and intraguild predation of P. volitans population with harvesting of adult P. volitans. The system undergoes a supercritical Hopf bifurcation when the invasiveness of P. volitans crosses a certain critical value. It is observed that cannibalism of P. volitans induces stability in the system even with high invasiveness of adult P. volitans. The dynamic instability of the system due to higher invasiveness of P. volitans can be controlled by increasing the rate of harvesting of P. volitans. It is also proven that P. volitans goes extinct when the harvest rate is greater than some critical threshold value. These results indicate that the dynamical behaviour of the model is very sensitive to the harvesting of P. volitans, which in turn is useful in the conservation of reef herbivores.

  20. BISPHENOL A AND ITS POTENTIAL TOXIC EFFECTS ON LIVING ORGANISMS

    Directory of Open Access Journals (Sweden)

    Irena Šutiaková

    2012-10-01

    Full Text Available Bisphenol A (BPA, 2, 2,-bis (4-hydroxyphenyl propane, CAS No. 80-05-7, is an industrial chemical that is made by combining acetone and phenol. Food is acknowledged to be a main source of exposure to BPA as a consequence of BPA migration from food containers. Several studies have reported BPA migrations from can surface coatings or plastics into foods and food-simulating liquids at high temperatures, and with repeated use of plastic products. Evaluation of BPA confirmed a no-observable adverse effect level (NOAEL of 5 mg/kg/body weight/day and established a maximum total daily intake (TDI of 0.05 mg/kg body weight. A metabolism of BPA is characterized mainly by phase II conjugation reactions in the gastrointestinal tract and in the liver. The presence of BPA in the environment can cause serious health problems (endocrine disruptions, neurotoxic, genotoxic and other problems. However, there are controversial opinions about BPA. Based on current knowledge of literature the need for further experimental studies in addressing health of human and animal populations living in different ecosystems may be still useful.

  1. Effect of Zeta Potential on the Properties of Nano-Drug Delivery ...

    African Journals Online (AJOL)

    Zeta potential is a scientific term for electrokinetic potential in colloidal systems which has a major effect on the various properties of nano-drug delivery systems. Presently, colloidal nano-carriers are growing at a remarkable rate owing to their strong potential for overcoming old challenges such as poor drug solubility and ...

  2. Finite Temperature Effective Potential for Spontaneously Broken $\\lambda \\Phi^4$ Theory

    OpenAIRE

    Nachbagauer, Herbert

    1994-01-01

    We present a self-consistent calculation of the finite temperature effective potential for $\\lambda \\Phi^4$ theory in four dimensions using a composite operator effective action. We find that in a spontaneously broken theory not only the so-called daisy and superdaisy graphs contribute to the next-to-leading order thermal mass, but also resummed non-local diagrams are of the same order, thus altering the effective potential at small effective mass.

  3. [Macrobenthos in Jinping reach of Yalongjiang River and its main tributaries].

    Science.gov (United States)

    Qu, Xiao-dong; Cao, Ming; Shao, Mei-ling; Li, Dao-feng; Cai, Qing-hua

    2007-01-01

    In this paper, an investigation was made on the macrobenthos at 25 sites in the Jinping reach of Yalongjiang River and its main tributaries in May and November 2004, aimed to study the relationships between macrobenthos distribution and environmental factors. The results showed that the dominant species of macrobenthos was Baetis sp. (Baetidae, Ephemeroptera), with a relative abundance being 14.9% and 27.0% in May and November, respectively. Based on the species composition and their relative abundance, and by using two-way indictor species analysis (TWINSPAN) and detrended correspondence analysis (DCA), the macrobenthods was divided into four groups, according to the habitat types of the sites. Canonical correspondence analysis (CCA) on the relationships between macrobenthods community structure and environmental factors indicated that in May, elevation and water hardness and NH4+ -N content were the main environmental factors affecting macrobenthods distribution, while in November, elevation, water hardness, NH4+ -N and SiO2 contents were the main ones.

  4. Continuous hydrological modelling in the context of real time flood forecasting in alpine Danube tributary catchments

    International Nuclear Information System (INIS)

    Stanzel, Ph; Kahl, B; Haberl, U; Herrnegger, M; Nachtnebel, H P

    2008-01-01

    A hydrological modelling framework applied within operational flood forecasting systems in three alpine Danube tributary basins, Traisen, Salzach and Enns, is presented. A continuous, semi-distributed rainfall-runoff model, accounting for the main hydrological processes of snow accumulation and melt, interception, evapotranspiration, infiltration, runoff generation and routing is set up. Spatial discretization relies on the division of watersheds into subbasins and subsequently into hydrologic response units based on spatial information on soil types, land cover and elevation bands. The hydrological models are calibrated with meteorological ground measurements and with meteorological analyses incorporating radar information. Operationally, each forecasting sequence starts with the re-calculation of the last 24 to 48 hours. Errors between simulated and observed runoff are minimized by optimizing a correction factor for the input to provide improved system states. For the hydrological forecast quantitative 48 or 72 hour forecast grids of temperature and precipitation - deterministic and probabilistic - are used as input. The forecasted hydrograph is corrected with an autoregressive model. The forecasting sequences are repeated each 15 minutes. First evaluations of resulting hydrological forecasts are presented and reliability of forecasts with different lead times is discussed.

  5. Dynamics and distribution of macrozoobenthos in the Toplica river, a tributary of the Kolubara

    Directory of Open Access Journals (Sweden)

    Živić Ivana

    2002-01-01

    Full Text Available Hydrobiological investigations of the macrozoobenthos were carried out at eight localities in the Toplica river (a right-hand tributary of the Kolubara river from April 2000 to January 2001. The bottom fauna was composed of 19 groups of macroinvertebrates with 85 determined taxa (61 identified to the species level, 24 to the generic level. The most varying groups were the insect orders Trichoptera (20 taxa, Ephemeroptera (15, and Diptera (13, while Isopoda, Decapoda, and insects belonging to orders Collembola, Heteroptera, Megaloptera, and Planipennia were the most uniform. The species Gammarus pulex fossarum Koch and Dugesia gonocephala Duges were the most abundant forms at the river source, and representatives of Ephemeroptera and Gammaridae were the most numerous in its upper course (at the second, third, and fourth locality. The Mollusca and Chironomidae larvae were the most abundant forms at the fifth locality (in the middle course, but no constant dominance of any animal group was recorded at the sixth one, where the dominance alternated among Chironomidae larvae (April, July 2000, Oligochaeta (October 2000 and Mollusca (January 2001. The lower course of the river (the seventh and eighth locality was characterized by the dominance of the species of the phylum Mollusca (Amphimelania holandri Ferussac, Fagotia esperi Ferussac and Theodoxus transversalis Pfeiffer.

  6. Morphological variation and phylogenetic analysis of the dinoflagellate Gymnodinium aureolum from a tributary of Chesapeake Bay.

    Science.gov (United States)

    Tang, Ying Zhong; Egerton, Todd A; Kong, Lesheng; Marshall, Harold G

    2008-01-01

    Cultures of four strains of the dinoflagellate Gymnodinium aureolum (Hulburt) G. Hansen were established from the Elizabeth River, a tidal tributary of the Chesapeake Bay, USA. Light microscopy, scanning electron microscopy, nuclear-encoded large sub-unit rDNA sequencing, and culturing observations were conducted to further characterize this species. Observations of morphology included: a multiple structured apical groove; a peduncle located between the emerging points of the two flagella; pentagonal and hexagonal vesicles on the amphiesma; production and germination of resting cysts; variation in the location of the nucleus within the center of the cell; a longitudinal ventral concavity; and considerable variation in cell width/length and overall cell size. A fish bioassay using juvenile sheepshead minnows detected no ichthyotoxicity from any of the strains over a 48-h period. Molecular analysis confirmed the dinoflagellate was conspecific with G. aureolum strains from around the world, and formed a cluster along with several other Gymnodinium species. Morphological evidence suggests that further research is necessary to examine the relationship between G. aureolum and a possibly closely related species Gymnodinium maguelonnense.

  7. Isotopic variation of oxygen in the water of river Solimoes/Amazon and its main tributaries

    International Nuclear Information System (INIS)

    Mortatti, J.; Martinelli, L.A.; Matsui, E.; Victoria, R.L.; Richey, J.E.

    1987-01-01

    Eight cruises in the Amazon Basin were realized during the period between April (1982) and August (1984). Waters of main channel of the River Solimoes/Amazon and its tributaries were sampled and analysed for sup(18)0 content by mass spectrometry. A depth integrated sampler coupled to a variable speed hydraulic winch was used. The sampling was accomplished at different river stages, at upper Solimoes, middle and lower Amazon region. The δ sup(18) 0 values obtained in these reaches showed the same seasonal variation pattern. In the dry season, δ sup(18) 0 values become higher than in the rainy season. The isotopic variability in the region may be explained by the origin and dynamics of the water vapour. The spatial variation in δ sup(18) 0 values at the main channel was compared for high and low water stages; it showed an isotopic gradient of 0.052 and 0.048 sup(0)/∞ δ sup(18) 0/100 km, respectively. (author)

  8. Brominated diphenyl ether levels. A comparison of tributary sediments versus biosolid material

    Energy Technology Data Exchange (ETDEWEB)

    Kolic, T.M.; MacPherson, K.A.; Reiner, E.J. [Ontario Ministry of the Environment, Laboratory Services Branch, Toronto, ON (Canada); Ho, T.; Kleywegt, S. [Ontario Ministry of the Environment, Standards Development Branch, Toronto, ON (Canada); Dove, A.; Marvin, C. [Environment Canada, Burlington, ON (Canada)

    2004-09-15

    PBDEs are persistent in the environment, have low water solubility and are known to have a tendency to bioaccumulate in wildlife and humans. There are 209 possible PBDE congeners. There has been concern over the bioaccumulation of these compounds since they have been found in mother's milk. Some of the brominated diphenyl ethers are known to metabolize into hydroxylated compounds and these metabolites are known to compete with and reduce thyroxine (T4) from binding to the thyroxine binding protein, transthyretin. This disrupts the thyroid hormone system interaction that has recently been notable amongst women in the form of hypothyroidism that can affect the fetus development in the form of neurodevelopmental deficits. There have been reports of estrogenic activities regarding PBDEs and their hydroxylated counterparts. Information such as this is indicative that PBDEs are endocrine disruptors. Due to their lipophilic nature, PBDEs have a high binding affinity to particulates and accumulate in sediments. Various reports on sediments and sludge type matrices have been reported in Austria, Switzerland, Netherlands and Canada. The following paper is a presentation of levels of PBDEs found in Tributary sediments and their comparison of levels to nearby biosolid sampling locations along Lake Ontario.

  9. Assessment of metal concentrations in sediment samples from Billings Reservoir, Rio Grande tributary, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Bostelmann, Eleine

    2006-01-01

    The present study chemically characterized sediment samples from the Billings reservoir, Rio Grande tributary, in the Metropolitan region of Sao Paulo, by determining metal concentration and other elements of interest. The chosen chemical parameters for this characterization were Aluminum, Arsenic, Barium, Cadmium, Copper, Chromium, Iron, Lead, Manganese, Mercury, Nickel, Selenium and Zinco. These parameters are also used in the water quality index, with the exception of Selenium. The concentrations were determined through different analytical techniques such as atomic absorption spectrometry (FAAS, GFAAS and CVAAS), optical emission spectrometry (ICP OES) and neutron activation analysis. These analytical methodologies were assessed for precision, accuracy and detection and/or quantification limits for the sediment elements in question. Advantages and disadvantages of each technique for each element and its concentration were also discussed. From these assessments the most adequate technique was selected for the routine analysis of sediment samples for each element concentration determination. This assessment verified also that digestion in a closed microwave system with nitric acid is efficient for the evaluation of extracted metals of environmental interest. The analytical techniques chosen were equally efficient for metals determination. In the case of Cd and Pb, the FAAS technique was selected due to better results than ICP OES, as it does not present matrix interference. The concentration values obtained for metals As, Cd, Cu, Cr, Hg, Ni, Pb and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) TEL and PEL values. (author)

  10. Assessment of metal concentrations in sediment samples from Billings reservoir, Rio Grande tributary, Sao Paulo, Brazil

    International Nuclear Information System (INIS)

    Bostelmann, Eleine

    2006-01-01

    The present study chemically characterized sediment samples from the Billings reservoir, Rio Grande tributary, in the Metropolitan region of Sao Paulo, by determining metal concentration and other elements of interest. The chosen chemical parameters for this characterization were Aluminum, Arsenic, Barium, Cadmium, Copper, Chromium, Iron, Lead, Manganese, Mercury, Nickel, Selenium and Zinc. These parameters are also used in the water quality index, with the exception of Selenium. The concentrations were determined through different analytical techniques such as atomic absorption spectrometry (FAAS, GFAAS and CVAAS), optical emission spectrometry (ICP OES) and neutron activation analysis. These analytical methodologies were assessed for precision, accuracy and detection and/or quantification limits for the sediment elements in question. Advantages and disadvantages of each technique for each element and its concentration were also discussed. From these assessment the most adequate technique was selected for the routine analysis of sediment samples for each element concentration determination. This assessment verified also that digestion in a closed microwave system with nitric acid is efficient for the evaluation of extracted metals of environmental interest. The analytical techniques chosen were equally efficient for metals determination. In the case of Cd and Pb, the FAAS technique was selected due to better results than ICP OES, as it does not present matrix interference. The concentration values obtained for metals As, Cd, Cu, Cr, Hg, Ni, Pb and Zn in the sediment samples were compared to Canadian Council of Minister of the Environment (CCME) TEL and PEL values. (author)

  11. Geo-inspired model: Agents vectors naturals inspired by the environmental management (AVNG of water tributaries

    Directory of Open Access Journals (Sweden)

    Edwin Eduardo Millán Rojas

    2018-02-01

    Full Text Available Context: Management to care for the environment and the Earth (geo can be source of inspiration for developing models that allow addressing complexity issues; the objective of this research was to develop an additional aspect of the inspired models. The geoinspired model has two features, the first covering aspects related to environmental management and the behavior of natural resources, and the second has a component of spatial location associated with existing objects on the Earth's surface. Method: The approach developed in the research is descriptive and its main objective is the representation or characterization of a case study within a particular context. Results: The result was the design of a model to emulate the natural behavior of the water tributaries of the Amazon foothills, in order to extend the application of the inspired models and allow the use of elements such as geo-referencing and environmental management. The proposed geoinspired model is called “natural vectors agents inspired in environmental management”. Conclusions: The agents vectors naturals inspired by the environmental are polyform elements that can assume the behavior of environmental entities, which makes it possible to achieve progress in other fields of environmental management (use of soil, climate, flora, fauna, and link environmental issues with the structure of the proposed model.

  12. Diel feeding ecology of Slimy Sculpin in a tributary to Skaneateles Lake, New York

    Science.gov (United States)

    Chalupnicki, Marc A.; Johnson, James H.

    2016-01-01

    Interactions among the benthic community are typically overlooked but play an important role in fish community dynamics. We examined the diel feeding ecology of Slimy Sculpin (Cottus cognatus) from Grout Brook, a tributary to Skaneateles Lake. Of the six time periods examined, Slimy Sculpin consumed the least during the nighttime (2400 h and 0400 h). Chironomids were the major prey consumed during all time periods except for 2400 h when ephemeropterans were the major prey consumed. There was a moderate preference by Slimy Sculpin for food from the benthos (0.59 ± 0.06) with Diptera (Chironomids), Ephemeroptera (Baetidae), and Trichoptera (Brachycentridae) representing the major taxa. Slimy Sculpin appear to be opportunistic feeders selecting what is most available in the brook. Index of fullness was variable and averaged 1.15% across the diel cycle. Daily ration was measured as a function of fish dry body weight and ranged from 0.12 to 0.22. Estimates of daily consumption ranged from 0.007% to 4.0% of body weight, which corresponds to reports for other species. These findings have application in gauging the relative importance of Slimy Sculpin in streams where highly valued salmonid species also occur.

  13. Oil sands development contributes polycyclic aromatic compounds to the Athabasca River and its tributaries

    Science.gov (United States)

    Kelly, Erin N.; Short, Jeffrey W.; Schindler, David W.; Hodson, Peter V.; Ma, Mingsheng; Kwan, Alvin K.; Fortin, Barbra L.

    2009-01-01

    For over a decade, the contribution of oil sands mining and processing to the pollution of the Athabasca River has been controversial. We show that the oil sands development is a greater source of contamination than previously realized. In 2008, within 50 km of oil sands upgrading facilities, the loading to the snowpack of airborne particulates was 11,400 T over 4 months and included 391 kg of polycyclic aromatic compounds (PAC), equivalent to 600 T of bitumen, while 168 kg of dissolved PAC was also deposited. Dissolved PAC concentrations in tributaries to the Athabasca increased from 0.009 μg/L upstream of oil sands development to 0.023 μg/L in winter and to 0.202 μg/L in summer downstream. In the Athabasca, dissolved PAC concentrations were mostly snow, dissolved PAC concentrations were up to 4.8 μg/L, thus, spring snowmelt and washout during rain events are important unknowns. These results indicate that major changes are needed to the way that environmental impacts of oil sands development are monitored and managed. PMID:19995964

  14. On the gluonic operator effective potential in holographic Yang-Mills theory

    Science.gov (United States)

    Kiritsis, Elias; Li, Wenliang; Nitti, Francesco

    2015-04-01

    The holographic formalism is applied to the calculation of the effective potential for the scalar glueball operator. Three different versions of this operator are defined, and for each we compute the associated effective potential and discuss its properties and scheme ambiguities. For one of them, the trace of the stress tensor, the potential is fixed by scale covariance and the conformal anomaly. Contact is made to earlier attempts to guess this effective potential from the conformal anomaly. We apply our results to the Improved Holographic QCD model calculating the glueball condensate.

  15. Non-standard perturbative methods for the effective potential in λφ4 QFT

    International Nuclear Information System (INIS)

    Okopinska, A.

    1986-07-01

    The effective potential in scalar QFT is calculated in the non-standard perturbative methods and compared with the conventional loop expansion. In the space time dimensions 0 and 1 the results are compared with the ''exact'' effective potential obtained numerically. In 4 dimensions we show that λφ 4 theory is non-interacting. (author)

  16. Two-loop effective potential for Wess-Zumino model using superfields

    International Nuclear Information System (INIS)

    Santos, R.P. dos; Srivastava, P.P.

    1985-10-01

    For the case of several interacting chiral superfields the propagators for the unconstrained superfield potentials in the 'shifted' theory, where the supersymmetry is explicitly broken, are derived in a compact form. They are used to compute one-loop effective potential in the general case, while a superfield calculation of renormalized effective potential to two loops for the Wess-Zumino model is performed. (author)

  17. Differentiation of Municipalities in São Paulo State based on Constitutional Transferences and Income Tributary Taxes

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Gouvêa

    2009-04-01

    Full Text Available This paper is part of a large study that combines several groups of municipalities in São Paulo State that are analyzed through multivariate statistical techniques. This study is intended to indicate whether the variables per capita transfer amounts from the Municipalities Participation Fund [MPF], Product and Service Circulation Tax Quota [ICMS] and collected tributary income have different average values among the municipalities of São Paulo State that present different economic and social situations according to the social responsibility index. The evaluation was carried out by multivariate analysis of variance. The results show that the tributary income has the greater difference of average among the groups. It was also found that MPF distribution criteria are applied differently and contribute to the available income fairness, giving support to local governments in the development of public policy.

  18. Towards the prevention of potential aluminum toxic effects and an effective treatment for Alzheimer's disease.

    Science.gov (United States)

    Percy, Maire E; Kruck, Theo P A; Pogue, Aileen I; Lukiw, Walter J

    2011-11-01

    In 1991, treatment with low dose intramuscular desferrioxamine (DFO), a trivalent chelator that can remove excessive iron and/or aluminum from the body, was reported to slow the progression of Alzheimer's disease (AD) by a factor of two. Twenty years later this promising trial has not been followed up and why this treatment worked still is not clear. In this critical interdisciplinary review, we provide an overview of the complexities of AD and involvement of metal ions, and revisit the neglected DFO trial. We discuss research done by us and others that is helping to explain involvement of metal ion catalyzed production of reactive oxygen species in the pathogenesis of AD, and emerging strategies for inhibition of metal-ion toxicity. Highlighted are insights to be considered in the quests to prevent potentially toxic effects of aluminum toxicity and prevention and intervention in AD. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Dams on Mekong tributaries as significant contributors of hydrological alterations to the Tonle Sap Floodplain in Cambodia

    Science.gov (United States)

    Arias, M. E.; Piman, T.; Lauri, H.; Cochrane, T. A.; Kummu, M.

    2014-12-01

    River tributaries have a key role in the biophysical functioning of the Mekong Basin. Of particular interest are the Sesan, Srepok, and Sekong (3S) rivers, which contribute nearly a quarter of the total Mekong discharge. Forty two dams are proposed in the 3S, and once completed they will exceed the active storage of China's large dam cascade in the Upper Mekong. Given their proximity to the Lower Mekong floodplains, the 3S dams could alter the flood-pulse hydrology driving the productivity of downstream ecosystems. Therefore, the main objective of this study was to quantify how hydropower development in the 3S, together with definite future (DF) plans for infrastructure development through the basin, would alter the hydrology of the Tonle Sap's Floodplain, the largest wetland in the Mekong and home to one of the most productive inland fisheries in the world. We coupled results from four numerical models representing the basin's surface hydrology, water resources development, and floodplain hydrodynamics. The scale of alterations caused by hydropower in the 3S was compared with the basin's DF scenario driven by the Upper Mekong dam cascade. The DF or the 3S development scenarios could independently increase Tonle Sap's 30-day minimum water levels by 30 ± 5 cm and decrease annual water level fall rates by 0.30 ± 0.05 cm day-1. When analyzed together (DF + 3S), these scenarios are likely to eliminate all baseline conditions (1986-2000) of extreme low water levels, a particularly important component of Tonle Sap's environmental flows. Given the ongoing trends and large economic incentives in the hydropower business in the region, there is a high possibility that most of the 3S hydropower potential will be exploited and that dams will be built even in locations where there is a high risk of ecological disruption. Hence, retrofitting current designs and operations to promote sustainable hydropower practices that optimize multiple river services - rather than just

  20. Influences of Stocking Salmon Carcass Analogs on Salmonids in Yakima River Tributaries, 2001-2002 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Pearsons, Todd N.; Johnson, Christopher L. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-04-01

    The benefits that marine derived nutrients from adult salmon carcasses provide to juvenile salmonids are increasingly being recognized. Current estimates suggest that only 6-7% of marine-derived nitrogen and phosphorus that were historically available to salmonids in the Pacific Northwest are currently available. Food limitation may be a major constraint limiting the restoration of salmonids. A variety of methods have been proposed to offset this nutrient deficit including: allowing greater salmon spawning escapement, stocking hatchery salmon carcasses, and stocking inorganic nutrients. Unfortunately, each of these methods has some ecological or socio-economic shortcoming. We intend to overcome many of these shortcomings by making and evaluating a pathogen free product that simulates a salmon carcass (analog). Abundant sources of marine derived nutrients are available such as fish offal from commercial fishing and salmon carcasses from hatcheries. However, a method for recycling these nutrients into a pathogen free analog that degrades at a similar rate as a natural salmon carcass has never been developed. We endeavored to (1) develop a salmon carcass analog that will increase the food available to salmonids, (2) determine the pathways that salmonids use to acquire food from analogs, and (3) determine the benefits to salmonids and the potential for application to salmonid restoration. We used a before-after-control-impact-paired design in six tributaries of the upper Yakima basin to determine the utility of stocking carcass analogs. Our preliminary results suggest that the introduction of carcass analogs into food-limited streams can be used to restore food pathways previously provided by anadromous salmon. The analogs probably reproduced both of the major food pathways that salmon carcasses produce: direct consumption and food chain enhancement. Trout and salmon fed directly on the carcass analogs during the late summer and presumably benefited from the increased

  1. Hydro-morphodynamics of open-channel confluences with low discharge ratio and dominant tributary sediment supply

    OpenAIRE

    Guillén Ludeña, Sebastián

    2015-01-01

    River confluences in which the tributary supplies the dominant sediment load, and the flow discharge is abundantly provided by the main river, are typically observed in mountain-river basins. The existent knowledge on the hydrodynamic, morphodynamic and sedimentary processes involved in mountain-river confluences is sparse, since most of the studies on confluence dynamics focus on low land confluences. In this context, the present research study aims to deepen the knowledge on the hydro-morph...

  2. Pesticides in the River Ravi and its tributaries between its stretches from Shahdara to Balloki Headworks, Punjab-Pakistan.

    Science.gov (United States)

    Akhtar, Mobeen; Mahboob, Shahid; Sultana, Salma; Sultana, Tayyaba

    2014-01-01

    The present study investigated the presence and potent source of pesticides and specific pesticide bearing effluent release points on the River Ravi, between the Shahdara and Balloki Headworks. Pakistan has banned the use of organochlorine and nitrogen containing pesticides, yet no attention has been paid to the continuous monitoring and assessment of these banned pesticides to make sure that they are not being used in practice. Levels of selected organochlorine and nitrogen containing pesticide residues were assessed in water collected from 18 sampling sites on the River Ravi and its tributaries using a gas chromatograph equipped with an electron capture detector (GC-ECD). All water samples were found to be contaminated with varying concentrations of pesticide residues. However, levels of pesticides were below the tolerance limits suggested in national and international standards. Pesticide concentrations in the water of river sites ranged from 0.034 to 0.045 microg/L for DDT, 0.033 to 0.046 microg/L for DDE, 0.108 to 0.123 microg/L for endosulfan and 0.028 to 0.040 microg/L for carbofuran. In tributaries, pesticide concentrations ranged from 0.0468 to 0.0685 microg/L for DDT, 0.0390 to 0.0637 microg/L for DDE, 0.111 to 0.147 microg/L for endosulfan and 0.0396 to 0.0631 microg/L for carbofuran. The results show pesticide concentrations in river water in the order: endosulfan > DDE > DDT > carbofuran. Pesticide concentrations in tributary waters decreased in the order: endosulfan > DDT> DDE > carbofuran. After Degh Fall and After Hudiara Nulla Fall river sampling sites were severely contaminated while, among the tributaries, Degh Fall and Hudiara Drain were severely contaminated with DDT, DDE, endosulfan and carbofuran. Constant monitoring programs should to be initiated to reform the present situation.

  3. Particle size of sediments collected from the bed of the Amazon River and its tributaries in June and July 1976

    Science.gov (United States)

    Nordin, Carl F.; Meade, R.H.; Mahoney, H.A.; Delany, B.M.

    1977-01-01

    Sixty-five samples of bed material were collected from the Amazon River and its major tributaries between Belem, Brazil, and Iquitos, Peru. Samples were taken with a standard BM-54 sampler, a pipe dredge, or a Helley-Smith bedload sampler. Most of the samples have median diameters in the size range of fine to medium sand and contain small percentages of fine gravel. Complete size distributions are tabulated.

  4. Particle size of sediments collected from the bed of the Amazon River and its tributaries in May and June 1977

    Science.gov (United States)

    Nordin, Carl F.; Meade, R.H.; Curtis, W.F.; Bosio, N.J.; Delaney, B.M.

    1979-01-01

    One-hundred-eight samples of bed material were collected from the Amazon River and its major tributaries between Belem, Brazil , and Iquitos, Peru. Samples were taken with a standard BM-54 sampler or with pipe dredges from May 18 to June 5, 1977. Most of the samples have median diameters in the size range of fine to medium sand and contain small percentages of fine gravel. Complete size distributions are tabulated. (Woodard-USGS)

  5. Scalar potential from de Sitter brane in 5D and effective cosmological constant

    International Nuclear Information System (INIS)

    Ito, Masato

    2004-01-01

    We derive the scalar potential in zero mode effective action arising from a de Sitter brane embedded in five dimensions with bulk cosmological constant Λ. The scalar potential for a scalar field canonically normalized is given by the sum of exponential potentials. In the case of Λ = 0 and Λ > 0, we point out that the scalar potential has an unstable maximum at the origin and exponentially vanishes for large positive scalar field. In the case of Λ < 0, the scalar potential has an unstable maximum at the origin and a local minimum. It is shown that the positive cosmological constant in dS brane is reduced by negative potential energy of scalar at minimum and that effective cosmological constant depends on a dimensionless quantity. Furthermore, we discuss the fate of our universe including the potential energy of the scalar. (author)

  6. GC/MS Based Non-target Screening of Organic Contaminants in River Indus and its Tributaries in Sindh (Pakistan

    Directory of Open Access Journals (Sweden)

    Huma Shaikh1

    2014-06-01

    Full Text Available To investigate presence of organic contaminants in river Indus and its tributaries screening studies were carried out. Two years screening studies were based on four sampling campaigns in 13 sampling points out of which 9 sampling points belong to river Indus and its tributaries, 4 to municipal sewerage and 1 to industrial sewerage. Deconvolution Reporting Software (DRS was used to analyze scan data. Deconvolution is capable of screening the compounds whose peaks become invisible due to co-extracted compounds. Furthermore it significantly reduces analysis time and chromatographic resolution requirements. Results reveal that all the sampling points were greatly polluted with phthalate esters and tributyl phosphate (TBP. Apart from these, numerous long chain hydrocarbons, toxic phenols i.e. bisphenol A, analgesic i.e. ibuprofen and mefenamic acid, pesticides i.e. endosulfan, PCPIs, etc have significantly contaminated water bodies. In this screening analysis many compounds are identified that can be possible emerging contaminants and that are rarely documented. The identified contaminants are debated in accordance with their use, possible emission source and pathway. To the best of our knowledge this study holds first detailed screening of organic contaminants in river Indus and its tributaries. The information gathered in this analysis can be useful for future studies based on individual contamination in river Indus.

  7. Structure of the optimized effective Kohn-Sham exchange potential and its gradient approximations

    International Nuclear Information System (INIS)

    Gritsenko, O.; Van Leeuwen, R.; Baerends, E.J.

    1996-01-01

    An analysis of the structure of the optimized effective Kohn-Sham exchange potential v, and its gradient approximations is presented. The potential is decomposed into the Slater potential v s and the response of v s to density variations, v resp . The latter exhibits peaks that reflect the atomic shell structure. Kohn-Sham exchange potentials derived from current gradient approaches for the exchange energy are shown to be quite reasonable for the Slater potential, but they fail to approximate the response part, which leads to poor overall potentials. Improved potentials are constructed by a direct fit of v x with a gradient-dependent Pade approximant form. The potentials obtained possess proper asymptotic and scaling properties and reproduce the shell structure of the exact v x . 44 refs., 7 figs., 4 tabs

  8. A systematic review of intervention effects on potential mediators of children’s physical activity

    Directory of Open Access Journals (Sweden)

    Brown Helen

    2013-02-01

    Full Text Available Abstract Background Many interventions aiming to increase children’s physical activity have been developed and implemented in a variety of settings, and these interventions have previously been reviewed; however the focus of these reviews tends to be on the intervention effects on physical activity outcomes without consideration of the reasons and pathways leading to intervention success or otherwise. To systematically review the efficacy of physical activity interventions targeting 5-12 year old children on potential mediators and, where possible, to calculate the size of the intervention effect on the potential mediator. Methods A systematic search identified intervention studies that reported outcomes on potential mediators of physical activity among 5-12 year old children. Original research articles published between 1985 and April 2012 were reviewed. Results Eighteen potential mediators were identified from 31 studies. Positive effects on cognitive/psychological potential mediators were reported in 15 out of 31 studies. Positive effects on social environmental potential mediators were reported in three out of seven studies, and no effects on the physical environment were reported. Although no studies were identified that performed a mediating analysis, 33 positive intervention effects were found on targeted potential mediators (with effect sizes ranging from small to large and 73% of the time a positive effect on the physical activity outcome was reported. Conclusions Many studies have reported null intervention effects on potential mediators of children’s physical activity; however, it is important that intervention studies statistically examine the mediating effects of interventions so the most effective strategies can be implemented in future programs.

  9. Tumor prevalence and biomarkers of genotoxicity in brown bullhead (Ameiurus nebulosus) in Chesapeake Bay tributaries.

    Science.gov (United States)

    Pinkney, Alfred E; Harshbarger, John C; Karouna-Renier, Natalie K; Jenko, Kathryn; Balk, Lennart; Skarphéðinsdóttir, Halldóra; Liewenborg, Birgitta; Rutter, Michael A

    2011-12-01

    We surveyed four Chesapeake Bay tributaries for skin and liver tumors in brown bullhead (Ameiurus nebulosus). We focused on the South River, where the highest skin tumor prevalence (53%) in the Bay watershed had been reported. The objectives were to 1) compare tumor prevalence with nearby rivers (Severn and Rhode) and a more remote river (Choptank); 2) investigate associations between tumor prevalence and polynuclear aromatic hydrocarbons (PAHs) and alkylating agents; and 3) statistically analyze Chesapeake Bay bullhead tumor data from 1992 through 2008. All four South River collections exhibited high skin tumor prevalence (19% to 58%), whereas skin tumor prevalence was 2%, 10%, and 52% in the three Severn collections; 0% and 2% in the Choptank collections; and 5.6% in the Rhode collection. Liver tumor prevalence was 0% to 6% in all but one South River collection (20%) and 0% to 6% in the three other rivers. In a subset of samples, PAH-like biliary metabolites and (32)P-DNA adducts were used as biomarkers of exposure and response to polycyclic aromatic compounds (PACs). Adducts from alkylating agents were detected as O6-methyl-2'-deoxyguanosine (O6Me-dG) and O6-ethyl-2'-deoxyguanosine (O6Et-dG) modified DNA. Bullheads from the contaminated Anacostia River were used as a positive control for DNA adducts. (32)P-DNA adduct concentrations were significantly higher in Anacostia bullhead livers compared with the other rivers. We identified alkyl DNA adducts in bullhead livers from the South and Anacostia, but not the Choptank. Neither the PAH-like bile metabolite data, sediment PAH data, nor the DNA adduct data suggest an association between liver or skin tumor prevalence and exposure to PACs or alkylating agents in the South, Choptank, Severn, or Rhode rivers. Logistic regression analysis of the Chesapeake Bay database revealed that sex and length were significant covariates for liver tumors and length was a significant covariate for skin tumors. Published by Elsevier B.V.

  10. Environmental DNA detection of rare and invasive fish species in two Great Lakes tributaries.

    Science.gov (United States)

    Balasingham, Katherine D; Walter, Ryan P; Mandrak, Nicholas E; Heath, Daniel D

    2018-01-01

    The extraction and characterization of DNA from aquatic environmental samples offers an alternative, noninvasive approach for the detection of rare species. Environmental DNA, coupled with PCR and next-generation sequencing ("metabarcoding"), has proven to be very sensitive for the detection of rare aquatic species. Our study used a custom-designed group-specific primer set and next-generation sequencing for the detection of three species at risk (Eastern Sand Darter, Ammocrypta pellucida; Northern Madtom, Noturus stigmosus; and Silver Shiner, Notropis photogenis), one invasive species (Round Goby, Neogobius melanostomus) and an additional 78 native species from two large Great Lakes tributary rivers in southern Ontario, Canada: the Grand River and the Sydenham River. Of 82 fish species detected in both rivers using capture-based and eDNA methods, our eDNA method detected 86.2% and 72.0% of the fish species in the Grand River and the Sydenham River, respectively, which included our four target species. Our analyses also identified significant positive and negative species co-occurrence patterns between our target species and other identified species. Our results demonstrate that eDNA metabarcoding that targets the fish community as well as individual species of interest provides a better understanding of factors affecting the target species spatial distribution in an ecosystem than possible with only target species data. Additionally, eDNA is easily implemented as an initial survey tool, or alongside capture-based methods, for improved mapping of species distribution patterns. © 2017 John Wiley & Sons Ltd.

  11. Tumor prevalence and biomarkers of genotoxicity in brown bullhead (Ameiurus nebulosus) in Chesapeake Bay tributaries

    Science.gov (United States)

    Pinkney, Alfred E.; Harshbarger, John C.; Karouna-Renier, Natalie K.; Jenko, Kathryn; Balk, Lennart; Skarphéðinsdóttir, Halldora; Liewenborg, Birgitta; Rutter, Michael A.

    2011-01-01

    We surveyed four Chesapeake Bay tributaries for skin and liver tumors in brown bullhead (Ameiurus nebulosus). We focused on the South River, where the highest skin tumor prevalence (53%) in the Bay watershed had been reported. The objectives were to 1) compare tumor prevalence with nearby rivers (Severn and Rhode) and a more remote river (Choptank); 2) investigate associations between tumor prevalence and polynuclear aromatic hydrocarbons (PAHs) and alkylating agents; and 3) statistically analyze Chesapeake Bay bullhead tumor data from 1992 through 2008. All four South River collections exhibited high skin tumor prevalence (19% to 58%), whereas skin tumor prevalence was 2%, 10%, and 52% in the three Severn collections; 0% and 2% in the Choptank collections; and 5.6% in the Rhode collection. Liver tumor prevalence was 0% to 6% in all but one South River collection (20%) and 0% to 6% in the three other rivers. In a subset of samples, PAH-like biliary metabolites and 32P-DNA adducts were used as biomarkers of exposure and response to polycyclic aromatic compounds (PACs). Adducts from alkylating agents were detected as O6-methyl-2'-deoxyguanosine (O6Me-dG) and O6-ethyl-2'-deoxyguanosine (O6Et-dG) modified DNA. Bullheads from the contaminated Anacostia River were used as a positive control for DNA adducts. 32P-DNA adduct concentrations were significantly higher in Anacostia bullhead livers compared with the other rivers. We identified alkyl DNA adducts in bullhead livers from the South and Anacostia, but not the Choptank. Neither the PAH-like bile metabolite data, sediment PAH data, nor the DNA adduct data suggest an association between liver or skin tumor prevalence and exposure to PACs or alkylating agents in the South, Choptank, Severn, or Rhode rivers. Logistic regression analysis of the Chesapeake Bay database revealed that sex and length were significant covariates for liver tumors and length was a significant covariate for skin tumors.

  12. NUMERICAL STUDY ON COOLING EFFECT POTENTIAL FROM VAPORIZER DEVICE OF LPG VEHICLE

    Directory of Open Access Journals (Sweden)

    MUJI SETIYO

    2017-07-01

    Full Text Available Over fuel consumption and increased exhaust gas due to the A/C system have become a serious problem. On the other hand, the LPG-fueled vehicle provides potential cooling from LPG phase changes in the vaporizer. Therefore, this article presents the potential cooling effect calculation from 1998 cm3 spark ignition (SI engine. A numerical study is used to calculate the potential heat absorption of latent and sensible heat transfer during LPG is expanded in the vaporizer. Various LPG compositions are also simulated through the engine speed range from 1000 to 6000 rpm. The result shows that the 1998 cm3 engine capable of generating the potential cooling effect of about 1.0 kW at 1000 rpm and a maximum of up to 1.8 kW at 5600 rpm. The potential cooling effects from the LPG vaporizer contributes about 26% to the A/C system works on eco-driving condition.

  13. Effects of flexoelectricity and surface elasticity on piezoelectric potential in a bent ZnO nanowire

    Science.gov (United States)

    Zhang, Shuangzhe; Yao, Haiyan; Fan, Wenliang; Hao, Yu; Wu, Xudong; Hou, Dongyuan

    2017-01-01

    In this work, a rapid model is established to study the effects of flexoelectricity and surface elasticity on the piezoelectric potential of a bent ZnO nanowire. Based on the piezoelectric theory and core-surface model, the distribution of piezoelectric potential of the ZnO nanowire is investigated. The analytical solution shows that the flexoelectricity and surface elasticity both significantly influence the piezoelectric potential. However, the effect of flexoelectricity is longitudinal dependent, which vanishes on the top side of nanowire, but only left surface elasticity effect on the potential. Simulation results show that the maximum value of potential on the top side of nanowire is about ± 220.5mV, of which result is lower compared to other theoretical models, but it should be more reasonable.

  14. The Effects of growing Indian military potential on South Asian stability

    Science.gov (United States)

    2017-06-09

    response. Both sides will then be engaged in a series of actions and counteractions leading to a potential ascent up the escalation ladder. If...national power and military potential . The dangerous outcome associated with these actions is the primary cause of instability in South Asia. In this...THE EFFECTS OF GROWING INDIAN MILITARY POTENTIAL ON SOUTH ASIAN STABILITY A thesis presented to the Faculty of the U.S. Army

  15. Dynamical properties of non-ideal plasma on the basis of effective potentials

    Energy Technology Data Exchange (ETDEWEB)

    Ramazanov, T. S.; Kodanova, S. K.; Moldabekov, Zh. A.; Issanova, M. K. [IETP, Al-Farabi Kazakh National University, 71 Al-Farabi str., Almaty 050040 (Kazakhstan)

    2013-11-15

    In this work, stopping power has been calculated on the basis of the Coulomb logarithm using the effective potentials. Calculations of the Coulomb logarithm and stopping power for different interaction potentials and degrees of ionization are compared. The comparison with the data of other theoretical and experimental works was carried out.

  16. The effects of saliva on the erosive potential of three different wines

    NARCIS (Netherlands)

    Brand, H.S.; Tjoe Fat, G.M.; Veerman, E.C.I.

    2009-01-01

    Background:  The erosive potential of wine on teeth may be modified by the buffering capacity of saliva. This potential effect was studied for three different wines in vitro and in vivo. Methods:  The buffering capacity was studied in vitro by stepwise addition of small volumes of a dry white wine,

  17. The effects of water potential on some active forms of phosphorus in ...

    African Journals Online (AJOL)

    Immobilization and mobilization reactions of soil phosphorus depend on biological properties of soil and these soil properties strongly depend on the soil water potential. The objective of this study was to test the effects of water potential on some active forms of soil P. A semiarid soil classified as Calcic Haploxerept was ...

  18. Bicultural Effects on the Creative Potential of Chinese and French Children

    Science.gov (United States)

    Lau, Sing; Cheung, Ping Chung; Lubart, Todd; Tong, Toby M. Y.; Chu, Dennis H. W.

    2013-01-01

    This study examined possible bicultural effects on creative potential of children in four groups of Chinese and French children in Hong Kong and Paris. An international battery of widely used divergent measures (Wallach-Kogan Creativity Tests; WKCT) and newly constructed divergent-plus-integrative measures (Evaluation of Potential Creativity;…

  19. Quantum Nuclear Extension of Electron Nuclear Dynamics on Folded Effective-Potential Surfaces

    DEFF Research Database (Denmark)

    Hall, B.; Deumens, E.; Ohrn, Y.

    2014-01-01

    A perennial problem in quantum scattering calculations is accurate theoretical treatment of low energy collisions. We propose a method of extracting a folded, nonadiabatic, effective potential energy surface from electron nuclear dynamics (END) trajectories; we then perform nuclear wave packet...

  20. Agglomeration Determines Effects of Carbonaceous Nanomaterials on Soybean Nodulation, Dinitrogen Fixation Potential, and Growth in Soil

    Science.gov (United States)

    The potential effects of carbonaceous nanomaterials (CNMs) on agricultural plants are of concern. However, little research has been performed using plants cultivated to maturity in soils contaminated with various CNMs at different concentrations. Here, we grew soybean for 39 days...

  1. Finite-temperature effective potential of a system with spontaneously broken symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Zemskov, E.P. [Yaroslavl State Technical Univ. (Russian Federation)

    1995-12-01

    A quantum-mechanical system with spontaneously broken symmetry is considered the effective potential is determined, and it is shown that with reduction of temperature the system undergoes a phase transition of the first kind.

  2. The O(N) model: Calculation of the effective potential for arbitrary values of N

    International Nuclear Information System (INIS)

    Casalbuoni, R.; Castellani, E.; De Curtis, S.; Florence Univ.

    1983-01-01

    By using the technique of the effective action for composition operators, we present a calculation of the effective potential of the O(N) scalar model for arbitrary values of N. The potential is given as a truncation of a loop expansion, and reproduces the known results of the N->infinite limit. The potential shows a symmetry breaking for ''small'' values of the ''classical fields'', whereas it shows Landau-type singularities in the region of ''large'' value. However, these singularities are clearly an artifact of our approximation and the model is perfectly consistent in the low energy regime. (orig.)

  3. Comparative effectiveness research and big data: balancing potential with legal and ethical considerations.

    Science.gov (United States)

    Gray, Elizabeth Alexandra; Thorpe, Jane Hyatt

    2015-01-01

    Big data holds big potential for comparative effectiveness research. The ability to quickly synthesize and use vast amounts of health data to compare medical interventions across settings of care, patient populations, payers and time will greatly inform efforts to improve quality, reduce costs and deliver more patient-centered care. However, the use of big data raises significant legal and ethical issues that may present barriers or limitations to the full potential of big data. This paper addresses the scope of some of these legal and ethical issues and how they may be managed effectively to fully realize the potential of big data.

  4. Effects of tacrolimus on action potential configuration and transmembrane ion currents in canine ventricular cells.

    Science.gov (United States)

    Szabó, László; Szentandrássy, Norbert; Kistamás, Kornél; Hegyi, Bence; Ruzsnavszky, Ferenc; Váczi, Krisztina; Horváth, Balázs; Magyar, János; Bányász, Tamás; Pál, Balázs; Nánási, Péter P

    2013-03-01

    Tacrolimus is a commonly used immunosuppressive agent which causes cardiovascular complications, e.g., hypertension and hypertrophic cardiomyopathy. In spite of it, there is little information on the cellular cardiac effects of the immunosuppressive agent tacrolimus in larger mammals. In the present study, therefore, the concentration-dependent effects of tacrolimus on action potential morphology and the underlying ion currents were studied in canine ventricular cardiomyocytes. Standard microelectrode, conventional whole cell patch clamp, and action potential voltage clamp techniques were applied in myocytes enzymatically dispersed from canine ventricular myocardium. Tacrolimus (3-30 μM) caused a concentration-dependent reduction of maximum velocity of depolarization and repolarization, action potential amplitude, phase-1 repolarization, action potential duration, and plateau potential, while no significant change in the resting membrane potential was observed. Conventional voltage clamp experiments revealed that tacrolimus concentrations ≥3 μM blocked a variety of ion currents, including I(Ca), I(to), I(K1), I(Kr), and I(Ks). Similar results were obtained under action potential voltage clamp conditions. These effects of tacrolimus developed rapidly and were fully reversible upon washout. The blockade of inward currents with the concomitant shortening of action potential duration in canine myocytes is the opposite of those observed previously with tacrolimus in small rodents. It is concluded that although tacrolimus blocks several ion channels at higher concentrations, there is no risk of direct interaction with cardiac ion channels when applying tacrolimus in therapeutic concentrations.

  5. Differential effects of thioridazine enantiomers on action potential duration in rabbit papillary muscle

    DEFF Research Database (Denmark)

    Jensen, A. S.; Pennisi, C. P.; Sevcencu, C.

    2015-01-01

    with (+)-thioridazine. In this study we for the first time investigate the cardiotoxicity of the isolated thioridazine enantiomers and show their effects on ventricular repolarization. The effects of (+)-thioridazine, (-)-thioridazine, and racemate on the rabbit ventricular action potential duration (APD) were...... investigated in a randomized controlled blinded experiment. Action potentials were measured in papillary muscles isolated from 21 female rabbits, and the drug effect on 90% APD in comparison with control (DeltaDelta-APD90) was evaluated. Increasing concentrations of (+)-thioridazine and the racemate caused......The antipsychotic drug thioridazine has potential for treatment of multidrug-resistant microbes including tuberculosis but also causes cardiotoxic QT interval prolongation. Both thioridazine enantiomers have potent antimicrobial effects, but the neuroleptic effect primarily resides...

  6. Effects of group status and victim sex on female bystanders' responses to a potential party rape.

    Science.gov (United States)

    Katz, Jennifer; Colbert, Samuel; Colangelo, Liane

    2015-01-01

    This research examined bystander responses to 1 of 4 potential party rape scenarios. Undergraduate women (N = 249) imagined attending a party either alone or with three friends where a sober man led an intoxicated potential victim (either male or female) into a bedroom. After random assignment to conditions, participants reported on intent to help and barriers to helping the potential victim. In contrast to the classic bystander effect, bystanders in groups intended to offer more help than lone bystanders. Bystanders also intended to offer more help to potential female than male victims and experienced more barriers to helping male victims. Two of these barriers (lack of personal responsibility to help and identifying risk) explained the lower intentions to help potential male victims. Potential male victims were more likely than female victims to be perceived as gay, and bystanders reported the least intentions to help presumably gay men at risk.

  7. The effect of interatomic potential in molecular dynamics simulation of low energy ion implantation

    International Nuclear Information System (INIS)

    Chan, H.Y.; Nordlund, K.; Peltola, J.; Gossmann, H.-J.L.; Ma, N.L.; Srinivasan, M.P.; Benistant, F.; Chan, Lap

    2005-01-01

    Being able to accurately predict dopant profiles at sub-keV implant energies is critical for the microelectronic industry. Molecular Dynamics (MD), with its capability to account for multiple interactions as energy lowers, is an increasingly popular simulation method. We report our work on sub-keV implantation using MD and investigate the effect of different interatomic potentials on the range profiles. As an approximation, only pair potentials are considered in this work. Density Functional Theory (DFT) is used to calculate the pair potentials for a wide range of dopants (B, C, N, F, Si, P, Ga, Ge, As, In and Sb) in single crystalline silicon. A commonly used repulsive potential is also included in the study. Importance of the repulsive and attractive regions of the potential has been investigated with different elements and we show that a potential depicting the right attractive forces is especially important for heavy elements at low energies

  8. Effective Potential Energies and Transport Cross Sections for Atom-Molecule Interactions of Nitrogen and Nitrogen

    Science.gov (United States)

    Stallcop, James R.; Partridge, Harry; Levin, Eugene; Arnold, Jim (Technical Monitor)

    2001-01-01

    The potential energy surfaces for H2-N and N2-N interactions are calculated by accurate ab initio methods and applied to determine transport data. The results confirm that an effective potential energy for accurately determining transport properties can be calculated using a single orientation. A simple method is developed to determine the dispersion coefficients of effective potential energies Effective potential energies required for O2-O collisions are determ=ined. The H2-N, N2-N, O2-H, and O2-O collision integrals are calculated and tabulated for a large range of temperatures. The theoretical values of the N2-N and O2-O diffusion coefficients compare well with measured data available at room temperature.

  9. Effective Potential from the Generalized Time-Dependent Schrödinger Equation

    Directory of Open Access Journals (Sweden)

    Trifce Sandev

    2016-09-01

    Full Text Available We analyze the generalized time-dependent Schrödinger equation for the force free case, as a generalization, for example, of the standard time-dependent Schrödinger equation, time fractional Schrödinger equation, distributed order time fractional Schrödinger equation, and tempered in time Schrödinger equation. We relate it to the corresponding standard Schrödinger equation with effective potential. The general form of the effective potential that leads to a standard time-dependent Schrodinger equation with the same solution as the generalized one is derived explicitly. Further, effective potentials for several special cases, such as Dirac delta, power-law, Mittag-Leffler and truncated power-law memory kernels, are expressed in terms of the Mittag-Leffler functions. Such complex potentials have been used in the transport simulations in quantum dots, and in simulation of resonant tunneling diode.

  10. The potential effects of sodium bicarbonate, a major constituent from coalbed natural gas production, on aquatic life

    Science.gov (United States)

    Farag, Aïda M.; Harper, David D.

    2012-01-01

    The production water from coalbed natural gas (CBNG) extraction contains many constituents. The U.S. Environmental Protection Agency has established aquatic life criteria for some of these constituents, and it is therefore possible to evaluate their risk to aquatic life. However, of the major ions associated with produced waters, chloride is the only one with an established aquatic life criterion (U.S. Environmental Protection Agency, 1988). The focus of this research was NaHCO3, a compound that is a major constituent of coalbed natural gas produced waters in the Tongue and Powder River Basins. This project included laboratory experiments, field in situ experiments, a field mixing zone study, and a fishery presence/absence assessment. Though this investigation focuses on the Tongue and Powder River Basins, the information is applicable to other watersheds where sodium bicarbonate is a principle component of product water either from CBNG or from traditional or unconventional oil and gas development. These data can also be used to separate effects of saline discharges from those potentially posed by other constituents. Finally, this research effort and the additional collaboration with USGS Water Resources and Mapping, Bureau of Land Management, US Environmental Protection Agency, State of Montana, State of Wyoming, Montana State University, University of Wyoming, and others as part of a Powder River Aquatic Task Group, can be used as a model for successful approaches to studying landscapes with energy development. The laboratory acute toxicity experiments were completed with a suite of organisms, including 7 species of fish, 5 species of invertebrates, and 1 amphibian species. Experiments performed on these multiple species resulted in LC50s that ranged from 1,120 to greater than (>) 8,000 milligrams sodium bicarbonate per liter (mg NaHCO3/L) (also defined as 769 to >8,000 milligrams bicarbonate per liter (mg HCO3-/L) or total alkalinity expressed as 608 to >4

  11. RESEARCH ON HEAVY METAL POLLUTION OF THE RIVER MUREŞ IN HUNEDOARA COUNTY DUE TRIBUTARIES AFFECTED BY HUMAN ACTIVITIES, INDUSTRIAL AND MINING

    Directory of Open Access Journals (Sweden)

    SZOLLOSI-MOŢA ANDREI

    2014-05-01

    Full Text Available Mureş crosses over a length of 105 km, a broad tectonic corridor between mountains Şureanu, Poiana Rusca Mountains and the Apuseni Mountains in the north. Hunedoara County has significant quantities of mineral resources, mining specific activities effectively represents one of the main economic sectors. Ore processing gave rise to significant amounts of mining waste. Tailings dams and waste dumps obtained from ore processing in preparation plants are large and have led to changes in the morphology of the area. The purpose of this study is to examine the degree of pollution of the river Mures in Hunedoara county, with heavy metals due to various human activities. For monitoring and evaluation in terms of water quality of the river Mures and studying the degree and effects of pollution were collected and analyzed water samples from Mures River and tributaries from the main mining areas, such Certej. Samples were analyzed by emission spectrometry with inductively coupled plasma and the results of measurements allowed us to assess the degree of pollution of the aquatic environment and sediments . The effects of mining waste on the environment persists for a long time , even after the operation closed. Rehabilitation mining areas and those adjacent to improve the quality of life, as a prerequisite for sustainable development.

  12. Effect of Glucuronidation on the Potential of Kaempferol to Inhibit Serine/Threonine Protein Kinases

    NARCIS (Netherlands)

    Beekmann, Karsten; Haan, De Laura H.J.; Actis-Goretta, Lucas; Bladeren, Van Peter J.; Rietjens, Ivonne M.C.M.

    2016-01-01

    To study the effect of metabolic conjugation of flavonoids on the potential to inhibit protein kinase activity, the inhibitory effects of the dietary flavonol kaempferol and its major plasma conjugate kaempferol-3-O-glucuronide on protein kinases were studied. To this end, the inhibition of the

  13. Observability of the effects of curl-free magnetic vector potential on ...

    Indian Academy of Sciences (India)

    We discuss here the prediction, based on a formalism by the author, on the observable effects of a curl-free magnetic vector potential on the macroscale as against the microscale of the Aharonov–Bohm effect. A new quantum concept – the 'transition amplitude wave' – postulated in the formalism has already been shown to ...

  14. Effects of diazepam on auditory evoked potentials of rats elicited in a ten-tone paradigm

    NARCIS (Netherlands)

    Jongsma, M.L.A.; Rijn, C.M. van; Schaijk, W.J. van; Coenen, A.M.L.; Dirksen, R.

    2000-01-01

    The effect of diazepam on sensory gating was studied in rats, by measuring diazepam effects on Auditory Evoked Potentials (AEPs) elicited in a ten-tone paradigm. Trains of 10 repetitive tone-pip stimuli were presented. Rats (n=8) received 4 mg.kg-1 diazepam s.c. or vehicle, counterbalanced over two

  15. Effects of seed priming and water potential on seed germination and ...

    African Journals Online (AJOL)

    Poor crop establishment is a major problem in wheat production due to low soil moisture. Two experiments were undertaken to determine the effects of seed priming on seed germination and seedling emergence of wheat varieties. The first experiment determined the effects of water potentials (0, -0.01, -0.1, -0.2, -0.5 and ...

  16. Environmentally Relevant Chemical Mixtures of Concern in Waters of U.S. Tributaries to the Great Lakes.

    Science.gov (United States)

    Elliott, Sarah M; Brigham, Mark E; Kiesling, Richard L; Schoenfuss, Heiko L; Jorgenson, Zachary G

    2018-03-08

    The North American Great Lakes are a vital natural resource that provide fish and wildlife habitat, as well as drinking water and waste assimilation services for millions of people. Tributaries to the Great Lakes receive chemical inputs from various point and non-point sources, and thus are expected to have complex mixtures of chemicals. However, our understanding of the co-occurrence of specific chemicals in complex mixtures is limited. To better understand the occurrence of specific chemical mixtures in the U.S. Great Lakes basin, surface water from 24 U.S. tributaries to the Laurentian Great Lakes was collected and analyzed for diverse suites of organic chemicals, primarily focused on chemicals of concern (e.g. pharmaceuticals, personal care products, fragrances, etc.). A total of 181 samples and 21 chemical classes were assessed for mixture compositions. Basin wide, 1,664 mixtures occurred in at least 25% of sites. The most complex mixtures identified were comprised of nine chemical classes and occurred in 58% of sampled tributaries. Pharmaceuticals typically occurred in complex mixtures, reflecting pharmaceutical-use patterns and wastewater facility outfall influences. Fewer mixtures were identified at lake or lake-influenced sites than at riverine sites. As mixture complexity increased, the probability of a specific mixture occurring more often than by chance greatly increased, highlighting the importance of understanding source contributions to the environment. This empirically-based analysis of mixture composition and occurrence may be used to focus future sampling efforts or mixture toxicity assessments. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Widespread dieback of riparian trees on a dammed ephemeral river and evidence of local mitigation by tributary flows

    Directory of Open Access Journals (Sweden)

    Caitlin M. S. Douglas

    2016-10-01

    Full Text Available Ephemeral rivers act as linear oases in drylands providing key resources to people and wildlife. However, not much is known about these rivers’ sensitivities to human activities. We investigated the landscape-level determinants of riparian tree dieback along the Swakop River, a dammed ephemeral river in Namibia, focusing on the native ana tree (Faidherbia albida and the invasive mesquite (Prosopis spp.. We surveyed over 1,900 individual trees distributed across 24 sites along a 250 km stretch of the river. General linear mixed models were used to test five hypotheses relating to three anthropogenic threats: river flow disruption from damming, human settlement and invasive species. We found widespread dieback in both tree populations: 51% mortality in ana tree, with surviving trees exhibiting 18% canopy death (median; and 26% mortality in mesquite, with surviving trees exhibiting 10% canopy death. Dieback in the ana tree was most severe where trees grew on drier stretches of the river, where tributary flow was absent and where mesquite grew more abundantly. Dieback in the mesquite, a more drought-tolerant taxon, did not show any such patterns. Our findings suggest that dieback in the ana tree is primarily driven by changes in river flow resulting from upstream dam creation and that tributary flows provide a local buffer against this loss of main channel flow. The hypothesis that the invasive mesquite may contribute to ana tree dieback was also supported. Our findings suggest that large dams along the main channels of ephemeral rivers have the ability to cause widespread mortality in downstream riparian trees. To mitigate such impacts, management might focus on the maintenance of natural tributary flows to buffer local tree populations from the disruption to main channel flow.

  18. Investigation of the effective potential barrier in the case of rare earth atoms

    International Nuclear Information System (INIS)

    Kiselev, A.A.; Karosene, A.V.; Karaziya, R.I.

    1975-01-01

    Based on the present tables on the Herman-Skilman potential, the potential barriers were determined for many neutral atoms and a few mathematical interrelationships in its change in the periodic system of elements are given. An analysis of the single parts in the exact effective Hartree-Fock potential was made and the change of the potential barrier in the isoelectronic series was investigated. By means of analyzing the behaviour of the single members in the effective potential, the change of the potential barrier when filling the 4fsup(N) shell in a series of neutral rare earth atoms is dealt with in this work and the special features of the 'collapse' of the shell containing a few electrons, as well as the dependence of the effective barrier on the atomic excitation and on the state of the configuration concerned, are also dealt with. The theoretical considerations are anticipated through the calculated results for potential barriers in rare earth atoms. (orig./LH) [de

  19. Chiral effective potential in N = {1/2} non-commutative Wess-Zumino model

    International Nuclear Information System (INIS)

    Banin, A.T.; Buchbinder, I.L.; Pletnev, N.G.

    2004-01-01

    We study a structure of holomorphic quantum contributions to the effective action for N = {1/2} noncommutative Wess-Zumino model. Using the symbol operator techniques we present the one-loop chiral effective potential in a form of integral over proper time of the appropriate heat kernel. We prove that this kernel can be exactly found. As a result we obtain the exact integral representation of the one-loop effective potential. Also we study the expansion of the effective potential in a series in powers of the chiral superfield φ and derivative D 2 φ and construct a procedure for systematic calculation of the coefficients in the series. We show that all terms in the series without derivatives can be summed up in an explicit form. (author)

  20. Non-perturbative effective potential: Lower bounds on the Higgs mass and dynamical applications

    International Nuclear Information System (INIS)

    Faivre, H.

    2006-01-01

    The purpose of this work was to assess the benefits of using non-perturbative methods to phenomenological issues in field theory. The exact equations of the Wilson renormalization group (RG) and the effective action have been used, we have computed the energy gap between the first 2 levels in double-well potential. We get a very good agreement with exact solutions inferring from the numerical solving of the Schroedinger equation. RG equations lead to a convex effective potential that is consistent with theory. We have considered the Higgs sector of the standard model. It is commonly acknowledged that the Yukawa coupling between the top quark and the Higgs boson generates the instability of the electroweak vacuum at high energy. We show that this instability does not exist, it is a mere consequence of the extrapolation of the RG equations beyond their validity range. We have also used the effective potential for the description of the time history of the mean value of the quantum field. We have defined the conditions under which the dynamics of the mean value can be described in the local potential approximation by classical equations of motion in which the effective potential replaces the classical potential. (A.C.)

  1. Influence of interface potential on the effective mass in Ge nanostructures

    International Nuclear Information System (INIS)

    Barbagiovanni, E. G.; Cosentino, S.; Terrasi, A.; Mirabella, S.; Lockwood, D. J.; Costa Filho, R. N.

    2015-01-01

    The role of the interface potential on the effective mass of charge carriers is elucidated in this work. We develop a new theoretical formalism using a spatially dependent effective mass that is related to the magnitude of the interface potential. Using this formalism, we studied Ge quantum dots (QDs) formed by plasma enhanced chemical vapour deposition (PECVD) and co-sputtering (sputter). These samples allowed us to isolate important consequences arising from differences in the interface potential. We found that for a higher interface potential, as in the case of PECVD QDs, there is a larger reduction in the effective mass, which increases the confinement energy with respect to the sputter sample. We further understood the action of O interface states by comparing our results with Ge QDs grown by molecular beam epitaxy. It is found that the O states can suppress the influence of the interface potential. From our theoretical formalism, we determine the length scale over which the interface potential influences the effective mass

  2. Polarization Potential Has No Effect on Maximum Current Density Produced by Halotolerant Bioanodes

    Directory of Open Access Journals (Sweden)

    Muriel González-Muñoz

    2018-03-01

    Full Text Available Halotolerant bioanodes are considered an attractive alternative in microbial electrochemical systems, as they can operate under higher conductive electrolytes, in comparison with traditional wastewater and freshwater bioanodes. The dependency between energetic performance and polarization potential has been addressed in several works; however the vast majority discusses its effect when wastewater or freshwater inocula are employed, and fewer reports focus on inocula from highly-saline environments. Moreover, the effect of the polarization potential on current production is not fully understood. To determine if the polarization potential has a significant effect on current production, eight bioanodes were grown by chronoamperometry at positive and negative potentials relative to the reference electrode (+0.34 V/SHE and −0.16 V/SHE, in a three-electrode set-up employing sediments from a hyperhaline coastal lagoon. The maximum current density obtained was the same, despite the differences in the applied potential. Our findings indicate that even if differences in organic matter removal and coulombic efficiency are obtained, the polarization potential had no statistically significant effect on overall current density production.

  3. Distribution of selected halogenated organic compounds among suspended particulate, colloid, and aqueous phases in the Mississippi River and major tributaries

    Science.gov (United States)

    Rostad, C.E.; Daniel, S.R.

    2007-01-01

    Suspended particulate, colloid, and aqueous phases were separated and analyzed to determine spatial variation of specific organic compound transport associated with each phase in a dynamic river system. Sixteen sites along the Mississippi River and its major tributaries were sampled at low-flow conditions to maximize the possibility of equilibrium. Across the solubility range studied, the proportion transported by each phase depended on the compound solubility, with more water-soluble compounds (dacthal, trifluralin) transported predominantly in the aqueous phase and less-water soluble compounds (polychlorinated biphenyls, chlordane-related compounds) transported predominantly in the particulate and colloid phases. ?? 2007 Springer Science+Business Media, LLC.

  4. Fish assemblage composition in a tributary of the Mogi Guaçu river basin, southeastern Brazil

    OpenAIRE

    Oliveira, Alexandre Kannebley de; Garavello, Júlio César

    2003-01-01

    Fish assemblage composition and seasonal patterns of species abundance were studied in Cabaceiras stream, a tributary of the Mogi Guaçu river in São Paulo State, Brazil. Three stations were sampled monthly from June 1999 to May 2000 using sieves and small trawl net and gill nets. Fifteen fish families, 37 genera and 45 species were captured. Characiformes (27 spp.) and Siluriformes (13 spp.) were the most species-rich orders. Gymnotiformes and Perciformes were represented by two species each,...

  5. Fish fauna from Sapucaí-Mirim River, tributary of Grande River, upper Paraná River basin, Southeastern Brazil

    OpenAIRE

    Oliveira,Alexandre Kannebley de; Garavello,Julio Cesar; Cesario,Vinicius Vendramini; Cardoso,Rodrigo Torres

    2016-01-01

    The fish species composition of Sapucaí-Mirim River is herein reported and discussed in the faunistic context of Grande and Paranaíba river basins, both formers of the Paraná River. The Sapucaí-Mirim is an important tributary of this hydrographic system, flowing to the left bank of Grande River in a region occupied by the reservoir of the Porto Colombia hydroelectric power plant, at São Paulo state northeastern region, in southeastern Brazil. The poorly known fish diversity of the Sapucaí-Mir...

  6. Effective potential in the strong-coupling lattice QCD with next-to-next-to-learning order effects

    International Nuclear Information System (INIS)

    Nakano, Takashi Z.; Miura, Kohtaroh; Ohnishi, Akira

    2010-01-01

    We derive an analytic expression of the effective potential at finite temperature (T) and chemical potential (μ) in the strong-coupling lattice QCD for color SU(3) including next-to-next-to-leading order (NNLO) effects in the strong coupling expansion. NNLO effective action terms are systematically evaluated in the leading order of the large dimensional (1/d) expansion, and are found to come from some types of connected two-plaquette configurations. We apply the extended Hubbard-Stratonovich transformation and a gluonic-dressed fermion technique to the effective action, and obtain the effective potential as a function of T, μ, and two order parameters: chiral condensate and vector potential field. The next-to-leading order (NLO) and NNLO effects result in modifications of the wave function renormalization factor, quark mass, and chemical potential. We find that T c,μ =0 and μ c,T =0 are similar to the NLO results, whereas the position of the critical point is sensitive to NNLO corrections. (author)

  7. Effect of potential attraction term on surface tension of ionic liquids

    Science.gov (United States)

    Vaziri, N.; Khordad, R.; Rezaei, G.

    2018-03-01

    In this work, we have studied the effect of attraction term of molecular potential on surface tension of ionic liquids (ILs). For this purpose, we have introduced two different potential models to obtain analytical expressions for the surface tension of ILs. The introduced potential models have different attraction terms. The obtained surface tensions in this work have been compared with other theoretical methods and also experimental data. Using the calculated surface tension, the sound velocity is also estimated. We have studied the structural effects on the surface tensions of imidazolium-based ionic liquids. It is found that the cation alkyl chain length and the anion size play important roles to the surface tension of the selected ionic liquids. The calculated surface tensions show a good harmony with experimental data. It is clear that the attraction term of molecular potential has an important role on surface tension and sound velocity of our system.

  8. Use of Continuous Monitors and Autosamplers to Predict Unmeasured Water-Quality Constituents in Tributaries of the Tualatin River, Oregon

    Science.gov (United States)

    Anderson, Chauncey W.; Rounds, Stewart A.

    2010-01-01

    Management of water quality in streams of the United States is becoming increasingly complex as regulators seek to control aquatic pollution and ecological problems through Total Maximum Daily Load programs that target reductions in the concentrations of certain constituents. Sediment, nutrients, and bacteria, for example, are constituents that regulators target for reduction nationally and in the Tualatin River basin, Oregon. These constituents require laboratory analysis of discrete samples for definitive determinations of concentrations in streams. Recent technological advances in the nearly continuous, in situ monitoring of related water-quality parameters has fostered the use of these parameters as surrogates for the labor intensive, laboratory-analyzed constituents. Although these correlative techniques have been successful in large rivers, it was unclear whether they could be applied successfully in tributaries of the Tualatin River, primarily because these streams tend to be small, have rapid hydrologic response to rainfall and high streamflow variability, and may contain unique sources of sediment, nutrients, and bacteria. This report evaluates the feasibility of developing correlative regression models for predicting dependent variables (concentrations of total suspended solids, total phosphorus, and Escherichia coli bacteria) in two Tualatin River basin streams: one draining highly urbanized land (Fanno Creek near Durham, Oregon) and one draining rural agricultural land (Dairy Creek at Highway 8 near Hillsboro, Oregon), during 2002-04. An important difference between these two streams is their response to storm runoff; Fanno Creek has a relatively rapid response due to extensive upstream impervious areas and Dairy Creek has a relatively slow response because of the large amount of undeveloped upstream land. Four other stream sites also were evaluated, but in less detail. Potential explanatory variables included continuously monitored streamflow

  9. Two loop effective Kahler potential of (non)-renormalizable supersymmetric models

    International Nuclear Information System (INIS)

    Groot Nibbelink, S.; Nyawelo, T.S.

    2005-10-01

    We perform a supergraph computation of the effective Kahler potential at one and two loops for general four dimensional N=1 supersymmetric theories described by arbitrary Kahler potential, superpotential and gauge kinetic function. We only insist on gauge invariance of the Kahler potential and the superpotential as we heavily rely on its consequences in the quantum theory. However, we do not require gauge invariance for the gauge kinetic functions, so that our results can also be applied to anomalous theories that involve the Green-Schwarz mechanism. We illustrate our two loop results by considering a few simple models: the (non-)renormalizable Wess-Zumino model and Super Quantum Electrodynamics. (author)

  10. Contamination, potential bias and humidity effects on electrical performance and corrosion reliability of electronic devices

    DEFF Research Database (Denmark)

    Piotrowska, Kamila; Verdingovas, Vadimas; Jellesen, Morten S.

    2015-01-01

    This paper describes the interactions between flux contamination, humidity and po-tential bias and their effect on corrosion reliability. Water layer formation on laminate surfaces and behavior of different solder flux chemistries with humid conditions have been studied, together with their influ......This paper describes the interactions between flux contamination, humidity and po-tential bias and their effect on corrosion reliability. Water layer formation on laminate surfaces and behavior of different solder flux chemistries with humid conditions have been studied, together...... with their influence on electrical performance of electronics. The effect of the type of laminate’s solder mask on the formation of water film and droplets was investigated for two different types: smooth glossy and rough matte sur-face finishes of the solder mask. The impact of potential bias on the electrical re...

  11. Measuring historic water levels of Lake Balaton and tributary wetlands using georeferenced maps

    Science.gov (United States)

    Zlinszky, A.

    2009-04-01

    that the topography of the lake floor has not changed measurably in the last hundred years. The bathymetric contours of Lake Balaton depicted on the georeferenced Krieger-map were digitized and overlain on the present-day DEM of the lake floor. The elevation profile of these lines was used to calculate the original elevation of the water level of the lake with the accuracy of one meter. The height of the water table around the lake depends closely on the water level of the lake, but wetlands can retain water and thus sustain a higher water table in the tributary valleys than in the lake itself. In order to measure the elevation of the water table around the lake, the borders of the water-logged areas on the southern shore of the lake were also digitized from the sheets of the First Military Survey and traced on a DEM of the hills on the southern side of the lake. The elevation of the water level in these wetlands was calculated based on these profiles. The water level in some valleys adjoining the lake is significantly higher than the water level of the lake itself, which shows that the water balance of these wetlands was mostly independent of the fluctuation of the lake. Some other large wetlands have borders that are in the same elevation as the shores of the lake itself, which shows that these wetlands are in close connection with the lake. The mapping of these historic wetland properties provides a valuable guide for future habitat restoration efforts.

  12. Pharmacodynamic Modelling of Placebo and Buprenorphine Effects on Event-Related Potentials in Experimental Pain

    DEFF Research Database (Denmark)

    Juul, Rasmus V; Foster, David J R; Upton, Richard N

    2014-01-01

    The purpose of the study was to investigate placebo and buprenorphine effects on event-related potentials (ERPs) in experimental pain and the potential benefit of population pharmacodynamic modelling in data analysis. Nineteen healthy volunteers received transdermal placebo and buprenorphine...... in a cross-over study. Drug plasma concentrations and ERPs after electrical stimulation at the median nerve with intensity adjusted to pain detection threshold were recorded until 144 hrs after administration. Placebo and concentration-effect models were fitted to data using non-linear mixed-effects...... modelling implemented in NONMEM (V7.2.0.). Pharmacodynamic models were developed to adequately describe both placebo and buprenorphine ERP data. Models predicted significant placebo effects, but did not predict significant effects related to buprenorphine concentration. Models revealed that ERPs varied both...

  13. Longitudinal gradient in limnological variables in the Upper Paraná River: a brief description and the importance of undammed tributaries

    Directory of Open Access Journals (Sweden)

    Natália Fernanda Santana

    2017-12-01

    Full Text Available Abstract Aim: Describe the limnological pattern in a longitudinal gradient in the Paraná River, a highly dammed river, in a stretch localized between two dams, but rich in undammed tributaries. Methods Twelve transects in the longitudinal gradient of the Paraná River were sampled, with the first transect being placed right after Porto Primavera dam, and the last one in the lotic region of the Itaipu dam. In each of these transects, water transparency, electrical conductivity, pH, total nitrogen and total phosphorous were analyzed. Results In those regions nearer Porto Primavera dam it was observed high values of water transparency and low values of nitrogen and phosphorous. The values of water transparency decreased and the values of nitrogen and phosphorous increased as the distance from Porto Primavera dam increased. Because the new tributaries connect to the Paraná River, with the sites farer from Porto Primavera dam presenting values similar to those prior its construction. Conclusions Increase in the nutrients concentration and changes in ecological integrity are probably due to the presence of the undammed tributaries. They are originate in different river basins and therefore contribute to the Paraná River in distinct manners. Results presented here are an indicative of the fundamental importance of undammed tributaries in mitigating damming negative impacts in extremely dammed rivers and highlight the importance of keeping such tributaries free of dams.

  14. Tributary trunk stream relations in a cut-and-fill landscape: a case study from Wolumla catchment, New South Wales, Australia

    Science.gov (United States)

    Brierley, Gary J.; Fryirs, Kirstie

    1999-05-01

    At the time of European settlement of the south coast of New South Wales, Australia, in the mid-nineteenth century, river courses were discontinuous throughout Wolumla catchment. Within a few decades of settlement, intact valley fills had been transformed into incised channels along trunk streams. This induced associated patterns of secondary incision into tributary valley fills. Three of the primary subcatchments in Wolumla catchment became fully incised, while an upland swamp and a floodout (i.e., sand sheet deposits atop an intact valley floor) remain in mid-catchment of the fourth subcatchment. Of the 70 lower order tributaries which join the trunk streams in the four subcatchments, 27 have incised (12 of which are discontinuously incised). Incision of tributary streams in Wolumla catchment cannot be explained by subcatchment area and slope relations. The position of the trunk stream channel within the valley floor trough is the key determinant of whether or not tributary streams have incised. Changes to river morphology since European settlement have altered the linkage of tributary streams to the trunk stream, impacting directly on the within-catchment transfer of water and sediment.

  15. Three-loop Standard Model effective potential at leading order in strong and top Yukawa couplings

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Stephen P. [Santa Barbara, KITP

    2014-01-08

    I find the three-loop contribution to the effective potential for the Standard Model Higgs field, in the approximation that the strong and top Yukawa couplings are large compared to all other couplings, using dimensional regularization with modified minimal subtraction. Checks follow from gauge invariance and renormalization group invariance. I also briefly comment on the special problems posed by Goldstone boson contributions to the effective potential, and on the numerical impact of the result on the relations between the Higgs vacuum expectation value, mass, and self-interaction coupling.

  16. A View of Water Quality Characteristics Pertinent to Phosphorus Movement in a Third Level Tributary to Lake Champlain

    Science.gov (United States)

    Witt, M.

    2017-12-01

    Lake Champlain is a large natural freshwater lake located in the northeastern United States. The lake provides fresh drinking water for over a quarter of a million people and affords for the livelihoods and recreational opportunities of many well beyond its borders. The health of Lake Champlain is important to the people of Vermont and beyond. During the summer months it is plagued by algal blooms. These unsightly and harmful growths affect other aquatic organisms and are the result of excess phosphate flowing into the lake. Missisquoi Bay in the far northern part of the lake is an area of concern. (Algal bloom Missisquoi Bay. Photo by Robert Galbraith) Measuring in-stream characteristics pertinent to phosphorus movement from the headwaters to the outflow of a third level tributary concurrently will provide important information regarding the movement of phosphorus into tributaries then on into Lake Champlain. Phosphorus, Total Suspended Solids, Temperature and Flow Rate were measured at the mouth, mid-point and headwaters of Black Creek. Black Creek is the last major contributor to the Missisquoi River before it flows into Missisquoi Bay, a bay in Lake Champlain. These measurements were made concurrently at low, normal and high water levels. Significant differences were found between temperature, total suspended solids and phosphate from the headwaters of Black Creek through to its outflow into the Missisquoi River. These characteristics pertinent to phosphorus movement indicated various rates of increase from headwaters to outflow.

  17. Fish assemblages and diversity in three tributaries of the Irrawaddy River in China: changes, threats and conservation perspectives

    Directory of Open Access Journals (Sweden)

    Yang M.-L.

    2016-01-01

    Full Text Available Incompletely known fish assemblages and species diversity are substantial obstacles in fish conservation, particularly when their aquatic habitats are under threat due to rapid human-induced changes. Fish assemblages and diversity in three tributaries of the upper Irrawaddy River in China (the Dulong, Daying and Ruili rivers were examined based on field collections and literature resources. The newly compiled fish assemblage recorded 85 species (in 8 orders, 20 families and 51 genera distributed in the upper Irrawaddy. The fish compositions in the Daying (67 species, 44 genera, 19 families, 7 orders and Ruili rivers (65 species, 44 genera, 19 families, 8 orders were more similar to each other and more speciose than that in the Dulong River (14 species, 10 genera, 4 families, 3 orders. Two indices of taxonomic diversity (the average taxonomic distinctness (Δ+, and the variation in taxonomic distinctness (Λ+ were used to discriminate four collections spanning a ten-year period. A decrease in taxonomic diversity and an increase in unevenness of the fish assemblages were found in both the Daying River and Ruili rivers, which indicated that the impacts were accumulated gradually during this decade, when dams and the spread of non-native species were major threats. Comparatively speaking, the Dulong River is still in a near-natural state, and thus the fish community has experienced less disturbance. In situ conservation (nature reserves and tributary protection and ex situ conservation (artificial propagation and release should be combined and managed to promote fish conservation in the future.

  18. Cumulative Effects of Micro-Hydro Development on the Fisheries of the Swan River Drainage, Montana, First Annual Progress Report (Covering Field Season July-November 1982).

    Energy Technology Data Exchange (ETDEWEB)

    Leathe, Stephen A.; Graham, Patrick J.

    1984-03-01

    This fisheries study is to determine the potential cumulative biological and economic effects of 20 small or micro-hydro-electric facilities (less than 5 megawatts) proposed to be constructed on tributaries to the Swan River, a 1738 square kilometer (671 square mile) drainage located in northwestern Montana. The study addresses portions of measure 1204 (b) (2) of the Norwthwest Power Planning Council's Columbia River Basin Fish and Wildlife Program. Aerial pre-surveys conducted during 1982 identified 102 stream reaches that may support fish populations in the Swan drainage between Swan and Lindbergh lakes. These reaches were located in 49 tributary streams and constituted 416 kilometers (258 miles) of potential fish habitat. Construction of all proposed small hydro projects would divert water from 54 kilometers (34 miles) or about 13 percent of the tributary system. Only two of the 20 proposed hydro sites did not support trout populations and most were populated by migratory bull trout and westslope cutthroat trout. Potential cumulative habitat losses that could result from dewatering of all proposed project areas were predicted using a stream reach classification scheme involving stream gradient, drainage ara, and fish population data. Preliminary results of this worst case analysis indicate that 23, 19 and 6 percent of the high quality rearing habitat for cutthroat, bull, and brook trout respectively would be lost.

  19. Effects of Acetylcholine and Noradrenalin on Action Potentials of Isolated Rabbit Sinoatrial and Atrial Myocytes

    Science.gov (United States)

    Verkerk, Arie O.; Geuzebroek, Guillaume S. C.; Veldkamp, Marieke W.; Wilders, Ronald

    2012-01-01

    The autonomic nervous system controls heart rate and contractility through sympathetic and parasympathetic inputs to the cardiac tissue, with acetylcholine (ACh) and noradrenalin (NA) as the chemical transmitters. In recent years, it has become clear that specific Regulators of G protein Signaling proteins (RGS proteins) suppress muscarinic sensitivity and parasympathetic tone, identifying RGS proteins as intriguing potential therapeutic targets. In the present study, we have identified the effects of 1 μM ACh and 1 μM NA on the intrinsic action potentials of sinoatrial (SA) nodal and atrial myocytes. Single cells were enzymatically isolated from the SA node or from the left atrium of rabbit hearts. Action potentials were recorded using the amphotericin-perforated patch-clamp technique in the absence and presence of ACh, NA, or a combination of both. In SA nodal myocytes, ACh increased cycle length and decreased diastolic depolarization rate, whereas NA decreased cycle length and increased diastolic depolarization rate. Both ACh and NA increased maximum upstroke velocity. Furthermore, ACh hyperpolarized the maximum diastolic potential. In atrial myocytes stimulated at 2 Hz, both ACh and NA hyperpolarized the maximum diastolic potential, increased the action potential amplitude, and increased the maximum upstroke velocity. Action potential duration at 50 and 90% repolarization was decreased by ACh, but increased by NA. The effects of both ACh and NA on action potential duration showed a dose dependence in the range of 1–1000 nM, while a clear-cut frequency dependence in the range of 1–4 Hz was absent. Intermediate results were obtained in the combined presence of ACh and NA in both SA nodal and atrial myocytes. Our data uncover the extent to which SA nodal and atrial action potentials are intrinsically dependent on ACh, NA, or a combination of both and may thus guide further experiments with RGS proteins. PMID:22754533

  20. Effects of Growth Environment and Ulking Rate on Cyanogenic Potential of Cassava Tuerous Roots

    International Nuclear Information System (INIS)

    Githunguri, C.M

    2002-01-01

    Various abiotic factors affect the pattern of growth and accumulation of cyanogenic glucosides in cassava plants. Five cassava genotypes were planted in a wet and a dry agro-ecological zone and analyzed at 4, 6, 8, 10 and 12 months after planting for tuberous root bulking rate and cyanogenic potential. Cassava plants at Ibadan (the wetter zone) had higher tuberous roots bulking rate and lower cynogenic potential than those planted at Minjibir (the drier zone). Root bulking rate at Ibadan increased from 4 to 6 months after planting, fell to 10 months, and then levelled off thereafter. At Majorana, bulking rate increased from 4 to 6 months, levelling off u pto 8 months after planting, and then falling slightly u pto to 10 months, and rising gradually u pto 12 months after planting. At Minijibir, the 6-8 months after planting period coincided with drought and the highest root bulking rate but increasing cyanogenic potential. Similarly, at Ibadan the 6-8 months after planting period coincided with drought and the highest root bulking rate but increasing cyanogenic potential. Despite the onset of drought, bulking continued up to 8 months after planting, falling u pto 10 months and levelling off thereafter at both agro-ecological zones. However, whereas cyanogenic potential rose rapidly after 8 months to peak at 10 months, and levelling off up to 12 months at Minjibir, cyanogenic potential levelled of after 8 u pto 12 months at Ibadan. Correlation and regression analysis suggested that root bulking rate and cyanogenic potential were negatively associated, meaning that an increase in root bulking rate would lead to corresponding decrease in it's cyanogenic potential which is highly desirable. This study has demonstrated that whereas the plant age and genotypic effects are not important factors in determining tuberous roots bulking rate and cyanogenic potential of cassava, the agro-ecological zone effect is an important factor in determining them

  1. Phenylephrine potentiates the anticonvulsant effect and neutralizes the sedative effect of diazepam in rats upon combined intragastric administration.

    Science.gov (United States)

    Serdyuk, S E; Gmiro, V E

    2014-12-01

    High doses of phenylephrine and diazepam (1 and 10 mg/kg, respectively) suppressed the development of generalized tonic-clonic pentylenetetrazole-induced convulsions in 86-100% rats, but did not prevent local clonic pentylenetetrazole-induced convulsions. Diazepam in the specified dose produced strong sedation, while phenylephrine had no sedative effect in the open-field test. Combined intragastric administration of phenylephrine in a medium and individually ineffective dose (0.3 mg/kg) and diazepam in a high dose (10 mg/kg) potentiated the anticonvulsant effect of diazepam: it prevented not only tonic-clonic, but also clonic pentylenetetrazole-induced convulsions in 100% rats and 2.6-fold increased anticonvulsant activity of diazepam. The specified combination of diazepam and phenylephrine had no sedative effect. The mechanism of potentiation of the anticonvulsive effect and elimination of the sedative side effect is based on stimulation of gastric mucosa afferents by phenylephrine.

  2. Reproductive endocrine-disrupting effects of triclosan: Population exposure, present evidence and potential mechanisms

    International Nuclear Information System (INIS)

    Wang, Cai-Feng; Tian, Ying

    2015-01-01

    Triclosan has been used as a broad-spectrum antibacterial agent for over 40 years worldwide. Increasing reports indicate frequent detection and broad exposure to triclosan in the natural environment and the human body. Current laboratory studies in various species provide strong evidence for its disrupting effects on the endocrine system, especially reproductive hormones. Multiple modes of action have been suggested, including disrupting hormone metabolism, displacing hormones from hormone receptors and disrupting steroidogenic enzyme activity. Although epidemiological studies on its effects in humans are mostly negative but conflicting, which is typical of much of the early evidence on the toxicity of EDCs, overall, the evidence suggests that triclosan is an EDC. This article reviews human exposure to triclosan, describes the current evidence regarding its reproductive endocrine-disrupting effects, and discusses potential mechanisms to provide insights for further study on its endocrine-disrupting effects in humans. - Highlights: • Triclosan is widely detected in human urine, blood and breast milk. • Laboratory studies suggest reproductive endocrine-disrupting effects of triclosan. • Laboratory studies suggest estrogenic properties of triclosan. • There are three potential mechanisms regarding the estrogenic effect of triclosan. • Prospective epidemiological studies on vulnerable populations are needed. - This review summarizes current evidence on human exposure to triclosan, and its reproductive endocrine-disrupting effects and potential mechanisms.

  3. Effects of pioglitazone on cardiac ion currents and action potential morphology in canine ventricular myocytes.

    Science.gov (United States)

    Kistamás, Kornél; Szentandrássy, Norbert; Hegyi, Bence; Ruzsnavszky, Ferenc; Váczi, Krisztina; Bárándi, László; Horváth, Balázs; Szebeni, Andrea; Magyar, János; Bányász, Tamás; Kecskeméti, Valéria; Nánási, Péter P

    2013-06-15

    Despite its widespread therapeutical use there is little information on the cellular cardiac effects of the antidiabetic drug pioglitazone in larger mammals. In the present study, therefore, the concentration-dependent effects of pioglitazone on ion currents and action potential configuration were studied in isolated canine ventricular myocytes using standard microelectrode, conventional whole cell patch clamp, and action potential voltage clamp techniques. Pioglitazone decreased the maximum velocity of depolarization and the amplitude of phase-1 repolarization at concentrations ≥3 μM. Action potentials were shortened by pioglitazone at concentrations ≥10 μM, which effect was accompanied with significant reduction of beat-to-beat variability of action potential duration. Several transmembrane ion currents, including the transient outward K(+) current (Ito), the L-type Ca(2+) current (ICa), the rapid and slow components of the delayed rectifier K(+) current (IKr and IKs, respectively), and the inward rectifier K(+) current (IK1) were inhibited by pioglitazone under conventional voltage clamp conditions. Ito was blocked significantly at concentrations ≥3 μM, ICa, IKr, IKs at concentrations ≥10 μM, while IK1 at concentrations ≥30 μM. Suppression of Ito, ICa, IKr, and IK1 has been confirmed also under action potential voltage clamp conditions. ATP-sensitive K(+) current, when activated by lemakalim, was effectively blocked by pioglitazone. Accordingly, action potentials were prolonged by 10 μM pioglitazone when the drug was applied in the presence of lemakalim. All these effects developed rapidly and were readily reversible upon washout. In conclusion, pioglitazone seems to be a harmless agent at usual therapeutic concentrations. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Effects of energy dependent Δ-nucleus optical potential in charge exchange reactions

    International Nuclear Information System (INIS)

    Helgesson, J.; Dmitriev, V.

    1994-01-01

    The Δ-nucleus optical potential from microscopic calculations in nuclear matter is used to study the effects of its energy dependence in charge-exchange (p, n) and ( 3 He, T) reactions. The neutron or triton spectrum is calculated via response function of a finite nucleus accounting for pion renormalization effects and short-range correlations. Only very small effects, 1-2%, were found for ( 3 He, T) reaction where the changes in the high energy part of the triton spectrum are enhanced relative to the low-energy part by ( 3 He, T) form factor. For the (p, n) reaction no visible effects were found. (orig.)

  5. Effect of an educational game on university students' learning about action potentials.

    Science.gov (United States)

    Luchi, Kelly Cristina Gaviao; Montrezor, Luís Henrique; Marcondes, Fernanda K

    2017-06-01

    The aim of this study was to evaluate the effect of an educational game that is used for teaching the mechanisms of the action potentials in cell membranes. The game was composed of pieces representing the intracellular and extracellular environments, ions, ion channels, and the Na + -K + -ATPase pump. During the game activity, the students arranged the pieces to demonstrate how the ions move through the membrane in a resting state and during an action potential, linking the ion movement with a graph of the action potential. To test the effect of the game activity on student understanding, first-year dental students were given the game to play at different times in a series of classes teaching resting membrane potential and action potentials. In all experiments, students who played the game performed better in assessments. According to 98% of the students, the game supported the learning process. The data confirm the students' perception, indicating that the educational game improved their understanding about action potentials. Copyright © 2017 the American Physiological Society.

  6. Interplay of infrared divergences and gauge dependence of the effective potential

    Science.gov (United States)

    Espinosa, J. R.; Garny, M.; Konstandin, T.

    2016-09-01

    The perturbative effective potential suffers infrared (IR) divergences in gauges with massless Goldstones in their minima (like the Landau or Fermi gauges), but the problem can be fixed by a suitable resummation of the Goldstone propagators. When the potential minimum is generated radiatively, gauge independence of the potential at the minimum also requires resummation, and we demonstrate that the resummation that solves the IR problem also cures the gauge-dependence issue, showing this explicitly in the Abelian Higgs model in the Fermi gauge. In the process, we find an IR divergence (in the first derivative of the potential) specific to the Fermi gauge and not appreciated in the recent literature. We show that physical observables can still be computed in this gauge, and we further show how to get rid of this divergence by a field redefinition. All these results generalize to the Standard Model case.

  7. Effects of electrolysis time and electric potential on chlorine generation of electrolyzed deep ocean water.

    Science.gov (United States)

    Hsu, Guoo-Shyng Wang; Lu, Yi-Fa; Hsu, Shun-Yao

    2017-10-01

    Electrolyzed water is a sustainable disinfectant, which can comply with food safety regulations and is environmentally friendly. A two-factor central composite design was adopted for studying the effects of electrolysis time and electric potential on the chlorine generation efficiency of electrolyzed deep ocean water (DOW). DOW was electrolyzed in a glass electrolyzing cell equipped with platinum-plated titanium anode and cathode. The results showed that chlorine concentration reached maximal level in the batch process. Prolonged electrolysis reduced chlorine concentration in the electrolyte and was detrimental to electrolysis efficiency, especially under high electric potential conditions. Therefore, the optimal choice of electrolysis time depends on the electrolyzable chloride in DOW and cell potential adopted for electrolysis. The higher the electric potential, the faster the chlorine level reaches its maximum, but the lower the electric efficiency will be. Copyright © 2016. Published by Elsevier B.V.

  8. Effect of quantity and composition of waste on the prediction of annual methane potential from landfills.

    Science.gov (United States)

    Cho, Han Sang; Moon, Hee Sun; Kim, Jae Young

    2012-04-01

    A study was conducted to investigate the effect of waste composition change on the methane production in landfills. An empirical equation for the methane potential of the mixed waste is derived based on the methane potential values of individual waste components and the compositional ratio of waste components. A correction factor was introduced in the equation and was determined from the BMP and lysimeter tests. The equation and LandGEM were applied for a full size landfill and the annual methane potential was estimated. Results showed that the changes in quantity of waste affected the annual methane potential from the landfill more than the changes of waste composition. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Effects of grid potentials and geometric dimensions on the multi-electrode probe measurements

    International Nuclear Information System (INIS)

    Elakshar, F.F.; Abdul El-Raoof, W.S.

    1986-01-01

    A hollow anode plasma source is used to produce low temperature plasma which is injected into a magnetic field. The effects of the grid potentials, collector potential and geometric dimensions on multi-electrode probe measurements, in the presence of a magnetic field, are investigated. It is found that the collector potential plays a substantial role in the measurement of temperatures and densities. The finite-size of the geometric dimensions of the probe influences the data and high values of temperature are obtained when a small ratio of the discriminator grid radius to the separation distance is used, providing that the repeller grid potentials is low. Reliable measurements can only be obtained if the multi-electrode probe is used in the presence of a magnetic field strong enough to reduce electron Larmor radii to less than the grid mesh radius. (author)

  10. The effect of empirical potential functions on modeling of amorphous carbon using molecular dynamics method

    International Nuclear Information System (INIS)

    Li, Longqiu; Xu, Ming; Song, Wenping; Ovcharenko, Andrey; Zhang, Guangyu; Jia, Ding

    2013-01-01

    Empirical potentials have a strong effect on the hybridization and structure of amorphous carbon and are of great importance in molecular dynamics (MD) simulations. In this work, amorphous carbon at densities ranging from 2.0 to 3.2 g/cm 3 was modeled by a liquid quenching method using Tersoff, 2nd REBO, and ReaxFF empirical potentials. The hybridization, structure and radial distribution function G(r) of carbon atoms were analyzed as a function of the three potentials mentioned above. The ReaxFF potential is capable to model the change of the structure of amorphous carbon and MD results are in a good agreement with experimental results and density function theory (DFT) at low density of 2.6 g/cm 3 and below. The 2nd REBO potential can be used when amorphous carbon has a very low density of 2.4 g/cm 3 and below. Considering the computational efficiency, the Tersoff potential is recommended to model amorphous carbon at a high density of 2.6 g/cm 3 and above. In addition, the influence of the quenching time on the hybridization content obtained with the three potentials is discussed.

  11. Effects of anisotropic potentials on the energy gap of Bose gas

    Directory of Open Access Journals (Sweden)

    F Nabipoor

    2010-09-01

    Full Text Available We investigate the effect of dipole-dipole and quadrapole- quadrapole interaction of a weakly interacting Bose gas near the transition temperature on the energy spectra of the thermal and condensate parts. We use the two fluid model and mean field approximation. We show that the effects of the condensate part on the shift of energy is greater than the case of contact potential

  12. The potentiation of the effect of radiation treatment by intratumoral delivery of cisplatin

    International Nuclear Information System (INIS)

    Yapp, Donald T.T.; Lloyd, David K.; Zhu, Julian; Lehnert, Shirley M.

    1998-01-01

    Purpose: To compare potentiation of the effects of acute or fractionated radiation by cisplatin when the drug was delivered intratumorally by implanted biodegradable polymer, by intraperitoneal injection, or by intraperitoneal osmotic pump. Methods and Materials: Radiation was delivered to a mouse tumor (RIF-1) either in a single dose or in a fractionated regime in conjunction with cisplatin delivered either as a bolus injection, with an osmotic pump, or with a biodegradable polymer rod containing cisplatin. The osmotic pump was implanted in the intraperitoneal cavity of the mouse while the polymer implants were placed directly in the tumor. As the polymer degrades, the drug is released at the treatment site leading to high local concentrations. The osmotic pump, in contrast, leads to prolonged systemic exposure to the drug at low concentrations. Tumor growth delay (TGD) was used as an endpoint in these experiments. Results: The most effective treatment protocol, in terms of potentiating the effects of radiation was cisplatin delivered by polymer implanted 2 days before an acute dose of radiation (growth modification factor [DMF] = 2.2). Comparison of single and multifraction regimes where polymer implant was on the same day as the commencement of treatment showed greater potentiation of the effect of fractionated than of acute radiation treatment with the DMF for fractionated treatment remaining relatively constant (1.5-1.9) for 5, 8, and 12 fraction treatments. Cisplatin delivered via the osmotic pump did not deliver a high enough dose of cisplatin to produce therapeutic effect in this mouse tumor model and had little impact on response to treatment. Conclusions: Our results indicated that cisplatin delivered intratumorally by biodegradable polymer implant was effective in potentiating the effect of both acute and fractionated radiation. For the fractionated treatments the effect was maintained with increasing fraction numbers and treatment time

  13. Potential Effect of Opium Consumption on Controlling Diabetes and Some Cardiovascular Risk Factors in Diabetic Patients

    OpenAIRE

    Rahimi, Najmeh; Gozashti, Mohamad Hossain; Najafipour, Hamid; Shokoohi, Mostafa; Marefati, Hamid

    2014-01-01

    Background Due to this belief that opium may have beneficial effects on diabetes or cardiovascular risk factors, the present study aimed to assess the potential and possible effects of opium consumption on diabetes control and some cardiovascular risk factors in diabetic patients. Methods This study enrolled 374 diabetic subjects from diabetes care centers in Kerman, Iran, including opium user group (n = 179) and a non-opium user group (n = 195). The data were collected through a questionnair...

  14. Potentiating effects of honey on antioxidant properties of lemon flavoured black tea

    OpenAIRE

    Pereira, Carla; Barros, Lillian; Vilas-Boas, Miguel; Ferreira, Isabel C.F.R.

    2013-01-01

    Health benefits including antioxidant potential of black tea (Camellia sinensis), lemon (Citrus limon) and honey bees (Apis mellifera) have been extensively reported. Nevertheless, nothing is reported about the effects of their concomitant use. Herein, those effects were evaluated in infusions of lemon-flavoured black tea with three different kinds of honey (light amber, amber and dark amber) from Lavandula stoechas, Erica sp. pl. and other indigenous floral species from north-east Portugal, ...

  15. Potential terrestrial fate and effects on soil biota of a coal liquefaction product spill

    Energy Technology Data Exchange (ETDEWEB)

    Strayer, R.F.; Edwards, N.T.; Walton, B.T.; Charles-Shannon, V.

    1983-01-01

    Contaminated soil samples collected from the site of a coal liquefaction product spill were used to study potential fates and effects of this synthetic fuel. Simulated weathering in the laboratory caused significant changes in residual oil composition. Soil column leachates contained high phenol levels that decreased exponentially over time. Toxicity tests demonstrated that the oil-contaminated soil was phytotoxic and caused embryotoxic and teratogenic effects on eggs of the cricket Acheta domesticus.

  16. Effects of light and temperature on the growth rate of potentially ...

    African Journals Online (AJOL)

    Thalassiosira allenii is a potentially harmful marine diatom distributed along the Northern Aegean and Southern Black Sea coasts of Turkey. In order to better understand the effect of environmental factors on T. allenii, the effects of 6 different light intensities (6.5, 38.7, 77.5, 116.2, 15 and 193.7 mmol/m2s (PAR)) and 4 ...

  17. Muscle Twitch Torque During Two Different in Volume Isometric Exercise Protocols: Fatigue Effects on Postactivation Potentiation.

    Science.gov (United States)

    Xenofondos, Anthi; Bassa, Eleni; Vrabas, Ioannis S; Kotzamanidis, Christos; Patikas, Dimitrios A

    2018-02-01

    Xenofondos, A, Bassa, E, Vrabas, IS, Kotzamanidis, C, and Patikas, D. Muscle twitch torque during two different in volume isometric exercise protocols: fatigue effects on postactivation potentiation. J Strength Cond Res 32(2): 578-586, 2018-The purpose of this study was to quantify the effect of the contraction duration of 2 isometric exercise protocols on the postactivation potentiation of 14 well-trained men (age: 22.6 ± 2.8 years, height: 180.3 ± 5.9 cm, and body mass: 72.3 ± 37.9 kg). The protocols consisted of 4 × 6 maximal plantar flexions, of 3-second (P3) or 6-second (P6) duration, performed in random order, with a 2-minute and 15-second intervals between the sets and repetitions, respectively. The torque during maximal isometric voluntary contraction (MIVC), the peak twitch torque (TT), and the rate of torque development (RTD) after each MIVC were analyzed for the first and the last trial of each set, the average of all trials of each set, and the trials within each set that had the highest peak TT. The MIVC had an overall greater reduction during P6 compared with P3 (P3: -4.6 ± 2.3 vs. P6: -16.0 ± 1.9%). P6 showed higher potentiation in TT during the initial repetitions of the first 2 sets (p twitch RTD presented no systematic difference between the 2 protocols (p > 0.05). These data demonstrate the dependence of the TT potentiation on the conditioning stimulus and verify the cumulative effect of potentiation, suggesting the implementation of longer contractions to achieve maximal but temporal TT potentiation and shorter contractions for less variable but prolonged potentiation.

  18. [Effect of pulse magnetic field on distribution of neuronal action potential].

    Science.gov (United States)

    Zheng, Yu; Cai, Di; Wang, Jin-Hai; Li, Gang; Lin, Ling

    2014-08-25

    The biological effect on the organism generated by magnetic field is widely studied. The present study was aimed to observe the change of sodium channel under magnetic field in neurons. Cortical neurons of Kunming mice were isolated, subjected to 15 Hz, 1 mT pulse magnetic stimulation, and then the currents of neurons were recorded by whole-cell patch clamp. The results showed that, under magnetic stimulation, the activation process of Na(+) channel was delayed, and the inactivation process was accelerated. Given the classic three-layer model, the polarization diagram of cell membrane potential distribution under pulse magnetic field was simulated, and it was found that the membrane potential induced was associated with the frequency and intensity of magnetic field. Also the effect of magnetic field-induced current on action potential was simulated by Hodgkin-Huxley (H-H) model. The result showed that the generation of action potential was delayed, and frequency and the amplitudes were decreased when working current was between -1.32 μA and 0 μA. When the working current was higher than 0 μA, the generation frequency of action potential was increased, and the change of amplitudes was not obvious, and when the working current was lower than -1.32 μA, the time of rising edge and amplitudes of action potential were decreased drastically, and the action potential was unable to generate. These results suggest that the magnetic field simulation can affect the distribution frequency and amplitude of action potential of neuron via sodium channel mediation.

  19. A simulation for predicting potential cooling effect on LPG-fuelled vehicles

    Science.gov (United States)

    Setiyo, M.; Soeparman, S.; Wahyudi, S.; Hamidi, N.

    2016-03-01

    Liquefied Petroleum Gas vehicles (LPG Vehicles) provide a potential cooling effect about 430 kJ/kg LPG consumption. This cooling effect is obtained from the LPG phase change from liquid to vapor in the vaporizer. In the existing system, energy to evaporate LPG is obtained from the coolant which is circulated around the vaporizer. One advantage is that the LPG (70/30 propane / butane) when expanded from 8 bar to at 1.2 bar, the temperature is less than -25 °C. These conditions provide opportunities to evaporate LPG with ambient air flow, then produce a cooling effect for cooling car's cabin. In this study, some LPG mix was investigated to determine the optimum condition. A simulation was carried out to estimate potential cooling effects of 2000 cc engine from 1000 rpm to 6000 rpm. In this case, the mass flow rate of LPG is a function of fuel consumption. The simulation result shows that the LPG (70/30 propane/butane) provide the greatest cooling effect compared with other mixtures. In conclusion, the 2000 cc engine fueled LPG at 3000 rpm provides potential cooling effect more than 1.3 kW, despite in the low engine speed (1000 rpm) only provides about 0.5 kW.

  20. Effects of inbreeding on potential and realized immune responses in Tenebrio molitor.

    Science.gov (United States)

    Rantala, Markus J; Viitaniemi, Heidi; Roff, Derek A

    2011-06-01

    Although numerous studies on vertebrates suggest that inbreeding reduces their resistance against parasites and pathogens, studies in insects have found contradictory evidence. In this study we tested the effect of 1 generation of brother-sister mating (inbreeding) on potential and realized immune responses and other life-history traits in Tenebrio molitor. We found that inbreeding reduced adult mass, pre-adult survival and increased development time, suggesting that inbreeding reduced the condition of the adults and thus potentially made them more susceptible to physiological stress. However, we found no significant effect of inbreeding on the potential immune response (encapsulation response), but inbreeding reduced the realized immune response (resistance against the entomopathogenic fungi, Beauveria bassiana). There was a significant family effect on encapsulation response, but no family effect on the resistance against the entomopathogenic fungi. Given that this latter trait showed significant inbreeding depression and that the sample size for the family-effect analysis was small it is likely that the lack of a significant family effect is due to reduced statistical power, rather than the lack of a heritable basis to the trait. Our study highlights the importance of using pathogens and parasites in immunoecological studies.

  1. Using Social Simulations to Assess and Train Potential Leaders to Make Effective Decisions in Turbulent Environments

    Science.gov (United States)

    Hunsaker, L. Phillip

    2007-01-01

    Purpose: The purpose of this paper is to describe two social simulations created to assess leadership potential and train leaders to make effective decisions in turbulent environments. One is set in the novel environment of a lunar moon colony and the other is a military combat command. The research generated from these simulations for assessing…

  2. Observability of the effects of curl-free magnetic vector potential on ...

    Indian Academy of Sciences (India)

    accepted conceptual framework which does not admit, as per the Lorentz equa- tion, any effect that a curl-free vector potential could have on the dynamics of a charged particle on the macroscale, and hence its detection. Such an observation has been predicted by a formalism developed by the author in a series of theo-.

  3. Effect of membrane potential on dialysis of calcium in a continuous-flow system.

    Science.gov (United States)

    Staley, M J; Farrance, I

    1978-12-01

    Electical potentials across the membrane in a modified AutoAnalyzer dialyzer (Technicon) have been determined under various conditions and related to the dialysis of 45Ca. The results suggest that anomalies in the diffusion of calcium from protein and nonprotein containing streams could be due to factors other than "Donnan equilibrium effects."

  4. Modelling the effects of soil water potential on growth and quality of cut chrysanthemum (Chrysanthemum morifolium)

    NARCIS (Netherlands)

    Lin, L.; Li, W.; Shao, J.; Luo, W.; Dai, J.; Yin, X.; Zhou, Y.; Zhao, C.

    2011-01-01

    A complete dynamic model was developed to describe the effects of soil water potential (WP) on the growth and external quality of standard cut chrysanthemum (Chrysanthemum morifolium) in order to optimise water management of greenhouse crops. Experiments using chrysanthemum cv. ‘Jinba’ with

  5. Effect of temperature on development and growth potential of axillary buds in roses

    NARCIS (Netherlands)

    Marcelis-van Acker, C.A.M.

    1995-01-01

    The effect of temperature during axillary bud formation on axillary bud development and subsequent shoot growth was investigated. Growth potential of the axillary buds was studied either in situ, by pruning the parent shoot above the bud, or in isolation, by grafting the bud or by culturing the bud

  6. Exoskeletons for industrial application and their potential effects on physical work load

    NARCIS (Netherlands)

    Looze, M.P. de; Bosch, T.; Krause, F.; Stadler, K.S.; O'Sullivan, L.W.

    2016-01-01

    The aim of this review was to provide an overview of assistive exoskeletons that have specifically been developed for industrial purposes and to assess the potential effect of these exoskeletons on reduction of physical loading on the body. The search resulted in 40 papers describing 26 different

  7. Potential effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on urban trees in the United States

    Science.gov (United States)

    David J. Nowak; Judith E. Pasek; Ronaldo A. Sequeira; Daniel E. Crane; Victor C. Mastro

    2001-01-01

    Anoplophora glabripennis Motschulsky, a wood borer native to Asia, was recently found in New York City and Chicago. In an attempt to eradicate these beetle populations, thousands of infested city trees have been removed. Field data from nine U.S. cities and national tree cover data were used to estimate the potential effects of A....

  8. Effect of surgery on sensory threshold and somatosensory evoked potentials after skin stimulation

    DEFF Research Database (Denmark)

    Lund, C; Hansen, O B; Kehlet, H

    1990-01-01

    We have studied the effect of surgical injury on cutaneous sensitivity and somatosensory evoked potentials (SSEP) to dermatomal electrical stimulation in 10 patients undergoing hysterectomy. Forty-eight hours after surgery, sensory threshold increased from 2.2 (SEM 0.3) mA to 4.4 (1.1) mA (P less...

  9. The potential effect of an HIV/AIDS vaccine in South Africa | Johnson ...

    African Journals Online (AJOL)

    This paper presents a model for assessing the potential effect of an HIV/AIDS vaccine in South Africa, and for calculating the amount of vaccine that would be required. A number of different hypothetical vaccine profiles and vaccine distribution strategies are considered. Results suggest that a sterilising vaccine could reduce ...

  10. The Effect of the Shape of Atomic Potential on the Diffraction Pattern ...

    African Journals Online (AJOL)

    We have simulated the diffraction patterns of both periodic and quasiperiodic monatomic chains using the code Laue (written by Silsbee and Drager) and investigated the effects of the shape of the atomic potential. Three fundamental differences between the diffraction patterns of periodic and quasiperiodic monatomic chain ...

  11. The effect of changes in perilymphatic K+ on the vestibular evoked potential in the guinea pig

    NARCIS (Netherlands)

    Kingma, C. M.; Wit, H. P.

    2010-01-01

    To investigate the effect on the functioning of the vestibular system of a rupture of Reissner's membrane, artificial endolymph was injected in scala media of ten guinea pigs and vestibular evoked potentials (VsEPs), evoked by vertical acceleration pulses, were measured. Directly after injection of

  12. Investigating aftergrowth potential of polymers in drinking water – the effect of water replacement and temperature

    DEFF Research Database (Denmark)

    Corfitzen, Charlotte B.; Albrechtsen, Hans-Jørgen

    no significant effect on the aftergrowth potential of the water. The background biomass production could be affected by the choice of caps for the test bottles, since ‘blue caps’ of polyethylene leached significant amounts of AOCP17 compared to ‘red caps’ containing teflon inlayers. There was no or only slightly...

  13. Effect of epidural 0.25% bupivacaine on somatosensory evoked potentials to dermatomal stimulation

    DEFF Research Database (Denmark)

    Lund, C; Hansen, O B; Kehlet, H

    1989-01-01

    The effect of lumbar epidural analgesia with similar volumes (about 25 ml) of 0.25% and 0.5% bupivacaine on early (less than 0.5 seconds) somatosensory evoked potentials (SEPs) to electrical stimulation of the S1, L1, and T10 dermatomes was examined in two groups of ten patients. Level of sensory...

  14. Effects of etidocaine administered epidurally on changes in somatosensory evoked potentials after dermatomal stimulation

    DEFF Research Database (Denmark)

    Lund, C; Hansen, O B; Kehlet, H

    1991-01-01

    The effect of lumbar epidural anesthesia with similar volumes (approximately 20 ml) of 1% and 1.5% etidocaine on early (less than 0.5 seconds) somatosensory evoked potentials (SEPs) to electrical stimulation of the S1, L1, and T10 dermatomes was examined in two groups of ten patients...

  15. Potential health effects of tobacco smoking in Uganda and how to ...

    African Journals Online (AJOL)

    Potential health effects of tobacco smoking in Uganda and how to overcome them through an appropriate communication strategy. ... East African Journal of Public Health ... Later, this paper suggests a communication strategy which can be adopted to convey scientific evidence to the public about the dangers of smoking.

  16. Effect of SRT and temperature on biological conversions and the related scum-forming potential

    NARCIS (Netherlands)

    Halalsheh, M.M.I.; Koppes, J.; Elzen, den J.; Zeeman, G.; Fayyad, M.; Lettinga, G.

    2005-01-01

    Sludge flotation was reported to cause several operational problems in anaerobic systems including UASB reactors treating both strong domestic sewage and some industrial wastewater. This research is to investigate the effect of anaerobic digestion on scum-forming potential (SFP) of sludge and other

  17. Retracted: Effects of pro-inflammatory cytokines on mineralization potential of rat dental pulp stem cells

    NARCIS (Netherlands)

    Yang, X.; Walboomers, X.F.; Bian, Z.; Jansen, J.A.; Fan, M.

    2011-01-01

    The following article from the Journal of Tissue Engineering and Regenerative Medicine, 'Effects of Pro-inflammatory Cytokines on Mineralization Potential of Rat Dental Pulp Stem Cells' by Yang X, Walboomers XF, Bian Z, Jansen JA, Fan M, published online on 11 July 2011 in Wiley Online Library

  18. Multivalley envelope function equations and effective potentials for phosphorus impurity in silicon

    Science.gov (United States)

    Klymenko, M. V.; Rogge, S.; Remacle, F.

    2015-11-01

    We propose a system of real-space envelope function equations without fitting parameters for modeling the electronic spectrum and wave functions of a phosphorus donor atom embedded in silicon. The approach relies on the Burt-Foreman envelope function representation and leads to coupled effective-mass Schrödinger equations containing smooth effective potentials. These potentials result from the spatial filtering imposed on the exact potential energy matrix elements in the envelope function representation. The corresponding filter function is determined from the definition of the envelope function. The resulting effective potentials and the system of envelope functions jointly reproduce the valley-orbit coupling effect in doped silicon. It is found that including the valley-orbit coupling not only of the 1 s but also for 2 s atomic orbitals, as well as static dielectric screening, is crucial to accurately reproduce experimental data. The measured binding energies are recovered with a maximum relative error of 1.53%. The computed wave functions are in good agreement with experimental measurements of the electron density provided by scanning tunneling microscopy.

  19. Effect of an Educational Game on University Students' Learning about Action Potentials

    Science.gov (United States)

    Luchi, Kelly Cristina Gaviao; Montrezor, Luís Henrique; Marcondes, Fernanda K.

    2017-01-01

    The aim of this study was to evaluate the effect of an educational game that is used for teaching the mechanisms of the action potentials in cell membranes. The game was composed of pieces representing the intracellular and extracellular environments, ions, ion channels, and the Na+-K+-ATPase pump. During the game activity, the students arranged…

  20. Shadow effect on photovoltaic potentiality analysis using 3D city models

    NARCIS (Netherlands)

    Alam, N.; Coors, V.; Zlatanova, S.; Van Oosterom, P.J.M.

    2012-01-01

    Due to global warming, green-house effect and various other drawbacks of existing energy sources, renewable energy like Photovoltaic system is being popular for energy production. The result of photovoltaic potentiality analysis depends on data quality and parameters. Shadow rapidly decreases

  1. Assessing Potential Climate Change Effects on Loblolly Pine Growth: A Probabilistic Regional Modeling Approach

    Science.gov (United States)

    Peter B. Woodbury; James E. Smith; David A. Weinstein; John A. Laurence

    1998-01-01

    Most models of the potential effects of climate change on forest growth have produced deterministic predictions. However, there are large uncertainties in data on regional forest condition, estimates of future climate, and quantitative relationships between environmental conditions and forest growth rate. We constructed a new model to analyze these uncertainties...

  2. Orientation effects on bipolar and other asymmetric membranes as observed by concentration potentials

    Czech Academy of Sciences Publication Activity Database

    Kůdela, Vlastimil; Richau, K.; Bleha, Miroslav; Paul, D.

    22-23, - (2001), s. 655-662 ISSN 1383-5866 R&D Projects: GA MŠk ME 079; GA AV ČR KSK2050602 Institutional research plan: CEZ:AV0Z4050913 Keywords : asymmetric membranes * concentration potentials * orientation effects Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.552, year: 2001

  3. Self-efficacy as a potential moderator of the effects of framed health messages

    NARCIS (Netherlands)

    Werrij, M.Q.; Ruiter, R.A.C.; Riet, van 't J.P.; Vries, de H.

    2011-01-01

    This study focuses on self-efficacy as a potential moderator of the effects of gain- and loss-framed health messages. Undergraduate students (N = 124) received a gain- or loss-framed message about consuming ecological meat. The data revealed that for participants high in self-efficacy, the

  4. Effect of Zeta Potential on the Properties of Nano-Drug Delivery ...

    African Journals Online (AJOL)

    The zeta potential (ZP) of colloidal systems and nano-medicines, as well as their particle size exert a major effect on the various properties of nano-drug delivery systems. Not only the stability of dosage forms and their release rate are affected but also their circulation in the blood stream and absorption into body membranes ...

  5. Developing Effective Earthquake Risk Reduction Strategies: The Potential Role of Academic Institutions in Lebanon

    Science.gov (United States)

    Baytiyeh, Hoda

    2015-01-01

    Lebanon faces the risk of powerful earthquakes with potentially devastating effects. However, the Lebanese people in general have not yet recognized this risk, as current educational programs and government officials have failed to inform them about it. This article discusses the essential role that Lebanese institutions of higher education should…

  6. The Rationale for Comparative Effectiveness of Tourist Potential Realization (Case Study of the Volga Region

    Directory of Open Access Journals (Sweden)

    Anna Nikolaevna Polukhina

    2016-11-01

    Full Text Available The article presents the analysis of long-term tourism development programs of the Volga Region. Great attention is given to the sector’s financing measures set out in development programs. Domestic and foreign tourist potential assessment methods are analyzed. Tourist potential dynamics of the Volga Region is studied based on expert opinion. Using econometric approach the authors study the correlation between tourism investments and incomes of the Volga Region for the past six years – from 2009 to 2014. The analysis was carried out using statistics provided by the Russian Tourism Association and the Federal State Statistics Service of the Russian Federation by category of profitability from paid tourist services and from hospitality and catering services. The conducted analysis helped construct the figures showing the differentiation of the Volga regions by tourism investment efficiency and tourist potential realization. It is shown that tourist potential of the territories and its realization are highly differentiated. The sub-regions of the Volga Region are divided into groups according to the effectiveness of potential realization. The effectiveness of implementation of natural recreational and historical and cultural potential is higher in the sub-regions where places of tourist accommodation and entertainment are developed enough, effective mechanisms for programs implementation control are formed and the indicators of expected effectiveness of measures implementation are elaborated. The study has revealed the need for the development of common indicators of expected final results of tourism development programs. The use of a unified system of standardized indicators should become the principle of monitoring the implementation of regional tourism development programs. Data obtained by the research will be useful for the improvement of the existing regional tourism development programs

  7. Numerical study of junction-angle effects on flow pattern in a river ...

    African Journals Online (AJOL)

    The effect of main channel curvature on the flow pattern in river junctions is a complex and important issue. The 3-dimensional flow pattern in a river bend with a lateral or tributary channel is not only affected by the centrifugal force and pressure gradient but is also affected by the tributary channel's momentum.

  8. Ultra-low dose naltrexone potentiates the anticonvulsant effect of low dose morphine on clonic seizures.

    Science.gov (United States)

    Honar, H; Riazi, K; Homayoun, H; Sadeghipour, H; Rashidi, N; Ebrahimkhani, M R; Mirazi, N; Dehpour, A R

    2004-01-01

    Significant potentiation of analgesic effects of opioids can be achieved through selective blockade of their stimulatory effects on intracellular signaling pathways by ultra-low doses of opioid receptor antagonists. However, the generality and specificity of this interaction is not well understood. The bimodal modulation of pentylenetetrazole-induced seizure threshold by opioids provide a model to assess the potential usefulness of this approach in seizure disorders and to examine the differential mechanisms involved in opioid anti- (morphine at 0.5-3 mg/kg) versus pro-convulsant (20-100 mg/kg) effects. Systemic administration of ultra-low doses of naltrexone (100 fg/kg-10 ng/kg) significantly potentiated the anticonvulsant effect of morphine at 0.5 mg/kg while higher degrees of opioid receptor antagonism blocked this effect. Moreover, inhibition of opioid-induced excitatory signaling by naltrexone (1 ng/kg) unmasked a strong anticonvulsant effect for very low doses of morphine (1 ng/kg-100 microg/kg), suggesting that a presumed inhibitory component of opioid receptor signaling can exert strong seizure-protective effects even at very low levels of opioid receptor activation. However, ultra-low dose naltrexone could not increase the maximal anticonvulsant effect of morphine (1-3 mg/kg), possibly due to a ceiling effect. The proconvulsant effects of morphine on seizure threshold were minimally altered by ultra-low doses of naltrexone while being completely blocked by a higher dose (1 mg/kg) of the antagonist. The present data suggest that ultra-low doses of opioid receptor antagonists may provide a potent strategy to modulate seizure susceptibility, especially in conjunction with very low doses of opioids.

  9. Potential and economic efficiency of using reduced tillage to mitigate climate effects in Danish agriculture

    DEFF Research Database (Denmark)

    Zandersen, Marianne; Jørgensen, Sisse Liv; Nainggolan, Doan

    2016-01-01

    , research also suggests that soil carbon stocks are declining. The scope of Payment for Ecosystem Service (PES) approaches to effectively and efficiently address climate regulation will depend on the spatial distribution of the carbon assimilation capacity, current land use, the value of avoided emissions...... and land owners’ objectives and preferences in terms of participating in initiatives to increase SOC. We map the carbon sequestration potential under different scenarios, value the potential sequestered carbon in terms of marginal costs of using voluntary agreements with agricultural land managers...... and compare these to the marginal abatement costs curve used in Danish climate policy. The cost effectiveness of reduced tillage as a climate mitigation PES scheme critically depends on the current debate on the net effects of carbon sequestration in reduced tillage practices. Based on existing IPCC...

  10. Under-examined aspects of the potential environmental effects of nuclear war

    Energy Technology Data Exchange (ETDEWEB)

    MacCracken, M.C.; Penner, J.E.

    1987-07-01

    In addition to destroying the area near the explosions, a nuclear war would lead to injection of a wide range of substances into the environment, both as a result of the delivery systems and explosions themselves and as a consequence of the blast, fires, and resulting destruction and disruption. While addressing the many remaining uncertainties concerning the effects of smoke injections on climate is the major topic of present research, there are a number of other potential impacts that could have major consequences, but which are currently poorly understood and have not yet been carefully examined. These under-examined effects include perturbations to atmospheric chemistry, the effects of injections of dust and water (which could create ice particles), the consequences of emissions from the smoldering phase of the fires, resuspension of materials due to perturbed surface conditions, and a range of other potential consequences.

  11. Effective potential and spontaneous symmetry breaking in the noncommutative φ6 model

    International Nuclear Information System (INIS)

    Barbosa, G.D.

    2004-01-01

    We study the conditions for spontaneous symmetry breaking of the (2+1)-dimensional noncommutative φ 6 model in the small-θ limit. In this regime, considering the model as a cutoff theory, it is reasonable to assume translational invariance as a property of the vacuum state and study the conditions for spontaneous symmetry breaking by an effective potential analysis. An investigation of up to the two-loop level reveals that noncommutative effects can modify drastically the shape of the effective potential. Under reasonable conditions, the nonplanar sector of the theory can become dominant and induce symmetry breaking for values of the mass and coupling constants not reached by the commutative counterpart

  12. Potential jurors' opinions on the effects of hypnosis on eyewitness identification: a brief communication.

    Science.gov (United States)

    Labelle, L; Lamarche, M C; Laurence, J R

    1990-10-01

    The present study examined a selected group of potential jurors' opinions on the effects of hypnosis on eyewitness identification and testimony. A group of 78 undergraduate psychology and optometry students completed a 2-part multiple choice questionnaire. The first part assessed Ss' knowledge of several issues concerning eyewitness testimony. The second part of the questionnaire contained 11 items which assessed Ss' beliefs and expectations concerning the effects of hypnosis on eyewitness identification and testimony. It was found that Ss' opinions on the effects of hypnosis on eyewitness testimony and identification were at odds with current empirical findings. These results, in accord with the previous literature, suggest that it is imperative that the courts be informed of the use of hypnosis during police work and that adequate precautions be taken to avoid a potential source of miscarriage of justice.

  13. Under-examined aspects of the potential environmental effects of nuclear war

    International Nuclear Information System (INIS)

    MacCracken, M.C.; Penner, J.E.

    1987-07-01

    In addition to destroying the area near the explosions, a nuclear war would lead to injection of a wide range of substances into the environment, both as a result of the delivery systems and explosions themselves and as a consequence of the blast, fires, and resulting destruction and disruption. While addressing the many remaining uncertainties concerning the effects of smoke injections on climate is the major topic of present research, there are a number of other potential impacts that could have major consequences, but which are currently poorly understood and have not yet been carefully examined. These under-examined effects include perturbations to atmospheric chemistry, the effects of injections of dust and water (which could create ice particles), the consequences of emissions from the smoldering phase of the fires, resuspension of materials due to perturbed surface conditions, and a range of other potential consequences

  14. [The birth of nanobiotechnologies: new nanomaterials, potential uses, toxic effects and implications for public health].

    Science.gov (United States)

    Petrinca, Anna Rita; Pietroiusti, Antonio; Argentin, Gabriella; Cicchetti, Rosadele; Donia, Domenica; Gabrieli, Rosanna; Vignoli, Isabella; Magrini, Andrea; Divizia, Maurizio

    2009-01-01

    Nanotechnologies hold considerable promise of advances in many sectors especially the biomedical field, since the materials used are of the appropriate dimensions to interact with important biological matter such as proteins, DNA and viruses. In this field the use of nanotechnologies will probably be second in importance only to biotechnologies. However many characteristics of nanomaterials that make them so promising from a technological point of view may also lead to negative effects on the environment and human health. It is important therefore that the environmental and work-related exposure effects to these materials be evaluated. In this article the potential uses, toxic effects and public health implications of nanobiotechnologies are discussed.

  15. Toxicity tests with crustaceans for detecting sublethal effects of potential endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Wollenberger, Leah

    on effects of potential endocrine disrupters on crustacean development and reproduction have been published since the beginning of the nineties. However, most crustacean toxicity test protocols routinely used so far have not been designed with endocrine-specific endpoints in mind. The main objectives...... of effective concentrations (ECx). After having demonstrated that larval development of A. tonsa was a very sensitive endpoint for evaluating effects of chemicals that might interfere with the endocrine system of crustaceans, the larval development test has been applied to two groups of emerging environmental...

  16. [Effect of the medium redox potential on the growth and metabolism of anaerobic bacteria].

    Science.gov (United States)

    Vasilian, A; Trchunian, A

    2008-01-01

    Based on the available literature data on a decrease in the redox potential of medium to low negative values and a decrease in pH during the growth of sugar-fermenting anaerobic bacteria, it was concluded that these processes cannot be described by the theory of redox potential. A theory was developed according to which the regulation of bacterial metabolism is accomplished through changes in the redox potential. The theory considers the redox potential as a factor determining the growth of anaerobic bacteria, which is regulated by oxidizers and reducers. The assumption is put forward that, under anaerobic conditions, bacteria are sensitive to changes in the redox potential and have a redox taxis. The effect of the redox potential on the transport of protons and other substances through membranes and the activity of membrane-bound enzymes, including the proton F1-F0-ATPase, whose mechanisms of action involve changes in the proton conductance of the membrane, the generation of proton-driving force, and dithiol-disulfide transitions in proteins was studied.

  17. Transient plasma potential in pulsed dual frequency inductively coupled plasmas and effect of substrate biasing

    Directory of Open Access Journals (Sweden)

    Anurag Mishra

    2016-09-01

    Full Text Available An electron emitting probe in saturated floating potential mode has been used to investigate the temporal evolution of plasma potential and the effect of substrate RF biasing on it for pulsed dual frequency (2 MHz/13.56 MHz inductively coupled plasma (ICP source. The low frequency power (P2MHz has been pulsed at 1 KHz and a duty ratio of 50%, while high frequency power (P13.56MHz has been used in continuous mode. The substrate has been biased with a separate bias power at (P12.56MHz Argon has been used as a discharge gas. During the ICP power pulsing, three distinct regions in a typical plasma potential profile, have been identified as ‘initial overshoot’, pulse ‘on-phase’ and pulse ‘off-phase’. It has been found out that the RF biasing of the substrate significantly modulates the temporal evolution of the plasma potential. During the initial overshoot, plasma potential decreases with increasing RF biasing of the substrate, however it increases with increasing substrate biasing for pulse ‘on-phase’ and ‘off-phase’. An interesting structure in plasma potential profile has also been observed when the substrate bias is applied and its evolution depends upon the magnitude of bias power. The reason of the evolution of this structure may be the ambipolar diffusion of electron and its dependence on bias power.

  18. Iterative optimized effective potential and exact exchange calculations at finite temperature

    International Nuclear Information System (INIS)

    Mattsson, Ann Elisabet; Modine, Normand Arthur; Muller, Richard Partain; Desjarlais, Michael Paul; Lippert, Ross A.; Sears, Mark P.; Wright, Alan Francis

    2006-01-01

    We report the implementation of an iterative scheme for calculating the Optimized Effective Potential (OEP). Given an energy functional that depends explicitly on the Kohn-Sham wave functions, and therefore, implicitly on the local effective potential appearing in the Kohn-Sham equations, a gradient-based minimization is used to find the potential that minimizes the energy. Previous work has shown how to find the gradient of such an energy with respect to the effective potential in the zero-temperature limit. We discuss a density-matrix-based derivation of the gradient that generalizes the previous results to the finite temperature regime, and we describe important optimizations used in our implementation. We have applied our OEP approach to the Hartree-Fock energy expression to perform Exact Exchange (EXX) calculations. We report our EXX results for common semiconductors and ordered phases of hydrogen at zero and finite electronic temperatures. We also discuss issues involved in the implementation of forces within the OEP/EXX approach.

  19. Biocide and corrosion inhibition use in the oil and gas industry: Effectiveness and potential environmental impacts

    International Nuclear Information System (INIS)

    Brandon, D.M.; Fillo, J.P.; Morris, A.E.; Evans, J.M.

    1995-01-01

    Treatment chemicals are used in all facets of the natural gas industry (NGI) from well development through transmission and storage of natural gas. The multitude of chemicals used, combined with the dozens of chemical manufacturers and/or suppliers has lead to the availability of hundreds of possible chemical products. Because of the widespread use of chemical products and their numerous sources, the NGI needs access to consistent data regarding their effectiveness and potential environmental impacts. The objective of this work was to evaluate the effectiveness and potential environmental impacts of, chemical products used in the NGI. This assessment was initially focused on biocides and corrosion inhibitors and their use in the gas production, storage and transmission facilities, The overall approach was obtain the necessary data on chemical use and effectiveness directly from the oil and gas industry, supplemented with data/information obtained from the published literature. Five case histories of chemical use were documented and evaluated to assess the effectiveness of these chemicals. Potential environmental impacts were addressed by performing a screening environmental assessment on the use of glutaraldehyde, a widely used biocide. Prototype discharge scenarios were formulated and modeled to evaluate potential impacts to groundwater and surface water. The paper describes the basis for the study, provides an overview of chemical use with a focus on biocides and corrosion inhibitors, describes and assesses the specific uses of chemicals, and presents the results of the environmental assessment. It was found that various chemicals can be effective in treating microbiologically influenced corrosion and souring, but that the effectiveness of specific chemicals is dependent on the operational scenario and the site-specific conditions

  20. Potential health effects of climatic change: Effects of increased ultraviolet radiation on man

    International Nuclear Information System (INIS)

    Urbach, F.

    1991-01-01

    There is scientific evidence that stratospheric ozone concentration has declined over the Northern Hemisphere in the past 20 years, and projections based on various assumption s about future release of chlorofluorocarbon gases and other contaminants suggest that this decline will continue into the next century. The effects on human health secondary to increase in biologically effective ultraviolet radiation are expected to consist of increases in nonmelanoma skin cancer and malignant melanoma of the skin, possible alteration of immune response, and development of lens cataracts. The recent and projected increases in skin cancer and changes in human immune responses are discussed. 19 refs