WorldWideScience

Sample records for water links gaps

  1. Bridging the Gap: Linking Simulation and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, Paul E.; Carsley, John; Stoudt, Mark R.; Hovanski, Yuri

    2012-09-01

    The Materials Genome Initiative (MGI) which is a key enabler for the Advanced Manufacturing Partnership, announced in 2011 by U.S. President Barack Obama, was established to accelerate the development and deployment of advanced materials. The MGI is driven by the need to "bridge the gap" between (I) experimental results and computational analysis to enable the rapid development and validation of new mateirals, and (II) the processes required to convert these materials into useable goods.

  2. Water limits to closing yield gaps

    Science.gov (United States)

    Davis, Kyle Frankel; Rulli, Maria Cristina; Garrassino, Francesco; Chiarelli, Davide; Seveso, Antonio; D'Odorico, Paolo

    2017-01-01

    Agricultural intensification is often seen as a suitable approach to meet the growing demand for agricultural products and improve food security. It typically entails the use of fertilizers, new cultivars, irrigation, and other modern technology. In regions of the world affected by seasonal or chronic water scarcity, yield gap closure is strongly dependent on irrigation (blue water). Global yield gap assessments have often ignored whether the water required to close the yield gap is locally available. Here we perform a gridded global analysis (10 km resolution) of the blue water consumption that is needed annually to close the yield gap worldwide and evaluate the associated pressure on renewable freshwater resources. We find that, to close the yield gap, human appropriation of freshwater resources for irrigation would have to increase at least by 146%. Most study countries would experience at least a doubling in blue water requirement, with 71% of the additional blue water being required by only four crops - maize, rice, soybeans, and wheat. Further, in some countries (e.g., Algeria, Morocco, Syria, Tunisia, and Yemen) the total volume of blue water required for yield gap closure would exceed sustainable levels of freshwater consumption (i.e., 40% of total renewable surface and groundwater resources).

  3. Development of Multidimensional Gap Conductance model using Virtual Link Gap Element

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyo Chan; Yang, Yong Sik; Kim, Dae Ho; Bang, Je Geon; Kim, Sun Ki; Koo, Yang Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The gap conductance that determines temperature gradient between pellet and cladding can be quite sensitive to gap thickness. For instance, once the gap size increases up to several micrometers in certain region, difference of pellet surface temperatures increases up to 100 Kelvin. Therefore, iterative thermo-mechanical coupled analysis is required to solve temperature distribution throughout pellet and cladding. Recently, multidimensional fuel performance codes have been being developed in the advanced countries to evaluate thermal behavior of fuel for off normal conditions and DBA(design based accident) conditions using the Finite Element Method (FEM). FRAPCON-FRAPTRAN code system, which is well known as the verified and reliable code, incorporates 1D thermal module and multidimensional mechanical module. In this code, multidimensional gap conductance model is not applied. ALCYONE developed by CEA introduces equivalent heat convection coefficient that represents multidimensional gap conductance as a function of gap thickness. BISON, which is multidimensional fuel performance code developed by INL, owns multidimensional gap conductance model using projected thermal contact. In general, thermal contact algorithm is nonlinear calculation which is expensive approach numerically. The gap conductance model for multi-dimension is difficult issue in terms of convergence and nonlinearity because gap conductance is function of gap thickness which depends on mechanical analysis at each iteration step. In this paper, virtual link gap (VLG) element has been proposed to resolve convergence issue and nonlinear characteristic of multidimensional gap conductance. In terms of calculation accuracy and convergence efficiency, the proposed VLG model was evaluated. LWR fuel performance codes should incorporate thermo-mechanical loop to solve gap conductance problem, iteratively. However, gap conductance in multidimensional model is difficult issue owing to its nonlinearity and

  4. Subharmonic energy-gap structure in superconducting weak links

    DEFF Research Database (Denmark)

    Flensberg, K.; Hansen, Jørn Bindslev; Octavio, M.

    1988-01-01

    We present corrected calculations of the subharmonic energy-gap structure using the model of Octavio, Tinkham, Blonder, and Klapwijk, which includes the effect of normal scattering in the weak link. We show that while the overall predictions of this model do not change qualitatively, the details...... of the predicted curves are different and in better agreement with experiment. We also present calculation of the current-voltage characteristics and of the excess currents for T=0, as the normal scattering parameter Z is varied. We also show how the calculation can be shortened using symmetry arguments...

  5. The missing link : bridging the gap between science and conservation

    NARCIS (Netherlands)

    Hoeven, van der C.A.

    2007-01-01

    Conservation biology is faced with an implementation crisis. This crisis is the result of a “knowledge-doing” or “assessment-planning” gap. One reason for this is that there is a discrepancy between systematic classical scientific assessments or surveys, and actual implementation in the field. This

  6. Formaldehyde cross-linking and structural proteomics: Bridging the gap.

    Science.gov (United States)

    Srinivasa, Savita; Ding, Xuan; Kast, Juergen

    2015-11-01

    Proteins are dynamic entities constantly moving and altering their structures based on their functions and interactions inside and outside the cell. Formaldehyde cross-linking combined with mass spectrometry can accurately capture interactions of these rapidly changing biomolecules while maintaining their physiological surroundings. Even with its numerous established uses in biology and compatibility with mass spectrometry, formaldehyde has not yet been applied in structural proteomics. However, formaldehyde cross-linking is moving toward analyzing tertiary structure, which conventional cross-linkers have already accomplished. The purpose of this review is to describe the potential of formaldehyde cross-linking in structural proteomics by highlighting its applications, characteristics and current status in the field. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Water service delivery - the weakest link

    CSIR Research Space (South Africa)

    Wall, K

    2009-05-01

    Full Text Available as strong as its weakest link at the time. • An integrated system …. Water and the poverty trap Poor level of water services Disease and sickness Spread of HIV/AIDS High cost for provision of household water and sanitation Limited employment... opportunities Education problems Skills deficiencies Loss of dignity POVERTY POOR WATER SUPPLY POOR SANITATION The poverty trap The poverty trap – Eastern Cape Eastern Cape Provincial “End of Term” Report (2009): • 7 out of 10 people in Eastern...

  8. Investigation of pulsed barrier discharge in water-air gap

    International Nuclear Information System (INIS)

    Taran, V.S.; Krasnyj, V.V.; Lozina, A.S.; Shvets, O.M.

    2013-01-01

    This article presents the results of the use of a pulsed dielectric barrier discharge with water electrode and diaphragm. The spectroscopic and electrical investigations of such discharge were conducted. The ozone concentration in an aqueous solution comprised 0.7 mg/l with high-voltage pulsed power at 120 W. The discharge reviewed emission spectrum lines of molecular nitrogen and hydroxyl radicals in the range of 200...800 nm in the water-air gap. The intensity changing of luminescence lines of OH and N 2 singles depending on the applied voltage and discharge gap has been determined. Aqueous solution of indigo was used in order to determine the impact level on the organic material. Experiments on inactivation of test E. coli cultures have been carried out.

  9. Trade Liberalization, Skill-linked Intermediate and Two-sided Wage Gap

    OpenAIRE

    Sugata Marjit; Rajat Achryya

    2005-01-01

    An interesting contemporary research question in trade theory deals with the possibility of rising wage inequality across the globe. A few possible explanations have been provided so far. We provide a natural explanation and a rigorous proof of the phenomenon by arguing that liberalizing trade in skill-linked intermediate product is likely to increase skilled-unskilled wage gap across the globe. Our model has the feature that a trade-induced shock can reduce the price of the skill-intensive t...

  10. Linking smallholder agriculture and water to household food security ...

    African Journals Online (AJOL)

    Linking smallholder agriculture and water to household food security and nutrition. ... Promoting household food security and reducing malnutrition rates of a growing population with the same amount of water is ... AJOL African Journals Online.

  11. Mind the gap: implementation challenges break the link between HIV/AIDS research and practice.

    Science.gov (United States)

    MacCarthy, Sarah; Reisner, Sari; Hoffmann, Michael; Perez-Brumer, Amaya; Silva-Santisteban, Alfonso; Nunn, Amy; Bastos, Leonardo; Vasconcellos, Mauricio Teixeira Leite de; Kerr, Ligia; Bastos, Francisco Inácio; Dourado, Inês

    2016-11-03

    Sampling strategies such as respondent-driven sampling (RDS) and time-location sampling (TLS) offer unique opportunities to access key populations such as men who have sex with men (MSM) and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic.

  12. Mind the gap: implementation challenges break the link between HIV/AIDS research and practice

    Science.gov (United States)

    MacCarthy, Sarah; Reisner, Sari; Hoffmann, Michael; Perez-Brumer, Amaya; Silva-Santisteban, Alfonso; Nunn, Amy; Bastos, Leonardo; de Vasconcellos, Mauricio Teixeira Leite; Kerr, Ligia; Bastos, Francisco Inácio; Dourado, Inês

    2018-01-01

    Sampling strategies such as respondent-driven sampling (RDS) and time-location sampling (TLS) offer unique opportunities to access key populations such as men who have sex with men (MSM) and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic. PMID:27828609

  13. Energy Gap, Microwave-Assisted Tunneling, and Josephson Steps in Thin-Film Weak Links at 63 and 302 GHz

    DEFF Research Database (Denmark)

    Kofoed, Bent; Særmark, Knud

    1973-01-01

    We present experimental evidence for the occurrence of energy-gap structure and microwave-assisted tunneling in the IV curves for superconducting thin-film weak links. From measurements of the power and the temperature dependence of the Josephson steps we argue that also the Riedel peak is observ......We present experimental evidence for the occurrence of energy-gap structure and microwave-assisted tunneling in the IV curves for superconducting thin-film weak links. From measurements of the power and the temperature dependence of the Josephson steps we argue that also the Riedel peak...

  14. Recurrent Anion Gap Acidosis: An Unusual Presentation of X-Linked Adrenoleukodystrophy in a Five-year-old Male.

    Science.gov (United States)

    Schwab, Joel; Pena, Loren; Sigman, Laura; Waggoner, Darrel

    2010-01-01

    We are presenting a five-year-old male with recurrent anion gap acidosis. During his last admission, it was detected that he had elevated VLCFA and the evaluation discovered that he had X-linked Adrenooleukodystrophy. He had the Addisonian only phenotype without any clinical or radiographic CNS findings. We were unable to find any other reports of this presentation of ALD. If the work-up of recurrent anion gap acidosis does not uncover an etiology, X-linked ALD should be considered in the differential diagnosis.

  15. Water2Invest: Global facility for calculating investments needed to bridge the climate-induced water gap

    Science.gov (United States)

    Straatsma, Menno; Droogers, Peter; Brandsma, Jairus; Buytaert, Wouter; Karssenberg, Derek; Meijer, Karen; van Aalst, Maaike; van Beek, Rens; Wada, Yoshihide; Bierkens, Marc

    2013-04-01

    Decision makers responsible for climate change adaptation investments are confronted with large uncertainties regarding future water availability and water demand, as well as the investment cost required to reduce the water gap. Moreover, scientists have worked hard to increase fundamental knowledge on climate change and its impacts (climate services), while practical use of this knowledge is limited due to a lack of tools for decision support under uncertain long term future scenarios (decision services). The Water2Invest project aims are to (i) assess the joint impact of climate change and socioeconomic change on water scarcity, (ii) integrate impact and potential adaptation in one flow, (iii) prioritize adaptation options to counteract water scarcity on their financial, regional socio-economic and environmental implications, and (iv) deliver all this information in an integrated user-friendly web-based service. Global water availability is computed between 2006 and 2100 using the PCR-GLOBWB water resources model at a 6 minute spatial resolution. Climate change scenarios are based on the fifth Assessment Report (AR5) of the IPCC Coupled Model Intercomparison Project (CMIP5) that defines four CO2 emission scenarios as representative concentration pathways. Water demand is computed for agriculture, industry, domestic, and environmental requirements based on socio-economic scenarios of increase in population and gross domestic product. Using a linear programming algorithm, water is allocated on a monthly basis over the four sectors. Based on these assessments, the user can evaluate various technological and infrastructural adaptation measures to assess the investments needed to bridge the future water gap. Regional environmental and socioeconomic effects of these investments are evaluated, such as environmental flows or downstream effects. A scheme is developed to evaluate the strategies on robustness and flexibility under climate change and scenario uncertainty

  16. Linking water treatment practices and fish welfare

    DEFF Research Database (Denmark)

    Zubiaurre, Claire; Pedersen, Lars-Flemming

    2016-01-01

    Peracetic acids can be used as sanitizers to control water quality in aquaculture systems. As an alternative to formalin, chloramine-T or copper sulphate, PAA has strong anti-microbial effects, degrades quickly and is relatively safe to use. Its mode of action and associated rapid decay can make....... Supportive enzymatic, biochemical and physiological biomarkers can be used along with gill and epidermal histological measures to evaluate the effects on water treatment regimens. The ultimate goal is to define the therapeutic window where fish welfare is not compromised.PAA is among the few disinfectants...

  17. Mind the gap: implementation challenges break the link between HIV/AIDS research and practice

    Directory of Open Access Journals (Sweden)

    Sarah MacCarthy

    Full Text Available Abstract: Sampling strategies such as respondent-driven sampling (RDS and time-location sampling (TLS offer unique opportunities to access key populations such as men who have sex with men (MSM and transgender women. Limited work has assessed implementation challenges of these methods. Overcoming implementation challenges can improve research quality and increase uptake of HIV services among key populations. Drawing from studies using RDS in Brazil and TLS in Peru, we summarize challenges encountered in the field and potential strategies to address them. In Brazil, study site selection, cash incentives, and seed selection challenged RDS implementation with MSM. In Peru, expansive geography, safety concerns, and time required for study participation complicated TLS implementation with MSM and transgender women. Formative research, meaningful participation of key populations across stages of research, and transparency in study design are needed to link HIV/AIDS research and practice. Addressing implementation challenges can close gaps in accessing services among those most burdened by the epidemic.

  18. Closing the 21st century global water gap: costs and effectiveness of adaptation measures

    Science.gov (United States)

    Bierkens, M. F.; Droogers, P.; Hunink, J.; Buitink, J.; Sutanudjaja, E.; Karssenberg, D.; Van Beek, L. P.; Straatsma, M. W.

    2017-12-01

    Water scarcity affects a major part of the globe, and is expected to increase significantly until 2100 as a result of climate change and socioeconomic developments. Yet, global projections are unavailable on the effectiveness and costs of adaptation measures to close the future water gap under global change. Here, we present a 21st century projection of the closure of the water gap under two contrasting climate and socio-economic scenarios: RCP2.6/SSP1(s1) and RCP8.5/SSP5(s5). We coupled a global hydrological model to water demand and redistribution model, and forced them with five General Circulation Models (GCMs) to assess the future water gap for 1604 water provinces covering most of the global land mass. Subsequently, using so-called water availability cost curves, we determined the water gap reduction that could be achieved by increasingly aggressive and expensive sets of adaptation measures, respectively aimed at improving agriculture, increasing water supply, and reducing water demands. Our results show that for s1, the water gap peaks around 2050 and declines towards 2100. Contrastingly, for s5, the gap increases linearly. Hotspots in water scarcity are found in the USA, India, and China. The proposed adaptation sets reduce the water gap, but for the majority of the hotspots are not sufficient to close the water gap completely. The median annual adaptation costs for the proposed measures amount to less than 2% of the GDP of the affected water provinces. Although these costs are already substantial, they do leave room for additional unorthodox adaptation measures.

  19. Material gap membrane distillation: A new design for water vapor flux enhancement

    KAUST Repository

    Francis, Lijo

    2013-08-19

    A new module design for membrane distillation, namely material gap membrane distillation (MGMD), for seawater desalination has been proposed and successfully tested. It has been observed that employing appropriate materials between the membrane and the condensation plate in an air gap membrane distillation (AGMD) module enhanced the water vapor flux significantly. An increase in the water vapor flux of about 200-800% was observed by filling the gap with sand and DI water at various feed water temperatures. However, insulating materials such as polypropylene and polyurethane have no effect on the water vapor flux. The influence of material thickness and characteristics has also been investigated in this study. An increase in the water gap width from 9. mm to 13. mm increases the water vapor flux. An investigation on an AGMD and MGMD performance comparison, carried out using two different commercial membranes provided by different manufacturers, is also reported in this paper. © 2013 Elsevier B.V.

  20. Bridging the Gap: Ideas for water sustainability in the western United States

    Science.gov (United States)

    Tidwell, V. C.; Passell, H. D.; Roach, J. D.

    2012-12-01

    Incremental improvements in water sustainability in the western U.S. may not be able to close the growing gap between increasing freshwater demand, climate driven variability in freshwater supply, and growing environmental consciousness. Incremental improvements include municipal conservation, improvements to irrigation technologies, desalination, water leasing, and others. These measures, as manifest today in the western U.S., are successful in themselves but limited in their ability to solve long term water scarcity issues. Examples are plainly evident and range from the steady and long term decline of important aquifers and their projected inability to provide water for future agricultural irrigation, projected declines in states' abilities to meet legal water delivery obligations between states, projected shortages of water for energy production, and others. In many cases, measures that can close the water scarcity gap have been identified, but often these solutions simply shift the gap from water to some other sector, e.g., economics. Saline, brackish or produced water purification, for example, could help solve western water shortages in some areas, but will be extremely expensive, and so shift the gap from water to economics. Transfers of water out of agriculture could help close the water scarcity gap in other areas; however, loss of agriculture will shift the gap to regional food security. All these gaps, whether in water, economics, food security, or other sectors, will have a negative impact on the western states. Narrowing these future gaps requires both technical and policy solutions as well as tools to understand the tradeoffs. Here we discuss several examples from across the western U.S. that span differing scales and decision spaces. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear

  1. Xylobolus subpileatus, a specialized basidiomycete functionally linked to old canopy gaps

    DEFF Research Database (Denmark)

    Taudiere, A.; Bellanger, J. M.; Moreau, P. A.

    2017-01-01

    Documenting succession in forest canopy gaps provides insights into the ecological processes governing the temporal dynamics of species within communities. We analyzed the fruiting patterns of a rare but widely distributed saproxylic macromycete, Xylobolus subpileatus, during the ageing of natura...

  2. Transport of Antarctic bottom water through the Kane Gap, tropical NE Atlantic Ocean

    NARCIS (Netherlands)

    Morozov, E.G.; Tarakanov, R.Y.; van Haren, H.

    2013-01-01

    We study low-frequency properties of the Antarctic Bottom Water (AABW) flow through the Kane Gap (9° N) in the Atlantic Ocean. The measurements in the Kane Gap include five visits with CTD (Conductivity-Temperature-Depth) sections in 2009–2012 and a year-long record of currents on a mooring using

  3. 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 ...

  4. A gap analysis of the South African innovation system for water ...

    African Journals Online (AJOL)

    A gap analysis of the South African innovation system for water. ... Two major approaches to science and innovation from the innovation systems ... infrastructure and data sharing; reorganising the research environment within universities; ...

  5. The gender gap reloaded: are school characteristics linked to labor market performance?

    Science.gov (United States)

    Konstantopoulos, Spyros; Constant, Amelie

    2008-06-01

    This study examines the wage gender gap of young adults in the 1970s, 1980s, and 2000 in the US. Using quantile regression we estimate the gender gap across the entire wage distribution. We also study the importance of high school characteristics in predicting future labor market performance. We conduct analyses for three major racial/ethnic groups in the US: Whites, Blacks, and Hispanics, employing data from two rich longitudinal studies: NLS and NELS. Our results indicate that while some school characteristics are positive and significant predictors of future wages for Whites, they are less so for the two minority groups. We find significant wage gender disparities favoring men across all three surveys in the 1970s, 1980s, and 2000. The wage gender gap is more pronounced in higher paid jobs (90th quantile) for all groups, indicating the presence of a persistent and alarming "glass ceiling."

  6. Linking the HOMO-LUMO gap to torsional disorder in P3HT/PCBM blends

    International Nuclear Information System (INIS)

    McLeod, John A.; Pitman, Amy L.; Moewes, Alexander; Kurmaev, Ernst Z.; Finkelstein, Larisa D.; Zhidkov, Ivan S.; Savva, Achilleas

    2015-01-01

    The electronic structure of [6,6]-phenyl C 61 butyric acid methyl ester (PCBM), poly(3-hexylthiophene) (P3HT), and P3HT/PCBM blends is studied using soft X-ray emission and absorption spectroscopy and density functional theory calculations. We find that annealing reduces the HOMO-LUMO gap of P3HT and P3HT/PCBM blends, whereas annealing has little effect on the HOMO-LUMO gap of PCBM. We propose a model connecting torsional disorder in a P3HT polymer to the HOMO-LUMO gap, which suggests that annealing helps to decrease the torsional disorder in the P3HT polymers. Our model is used to predict the characteristic length scales of the flat P3TH polymer segments in P3HT and P3HT/PCBM blends before and after annealing. Our approach may prove useful in characterizing organic photovoltaic devices in situ or even in operando

  7. Size Reduction of a DC Link Choke Using Saturation Gap and Biasing with Permanent Magnets

    DEFF Research Database (Denmark)

    Aguilar, Andres Revilla; Munk-Nielsen, Stig; Zuccherato, Marco

    2014-01-01

    This document describes the design procedure of permanent magnet biased DC inductors using the Saturation-gap technique [1]. This biasing configuration can provide a 50% reduction in either the core volume or the number of turns, while meeting its current and inductance requirements. A design exa...

  8. Gender Gap Linked to Differential Socialization for High-Achieving Senior Mathematics Students.

    Science.gov (United States)

    Campbell, James R.; Beaudry, Jeffrey S.

    1998-01-01

    Examined whether 11th-grade girls and boys enrolled in advanced mathematics courses nationwide were socialized in similar ways, using Campbell's differential socialization paradigm. Results uncovered a gender gap favoring boys. Self-imposed pressure and persistence had important direct effects on achievement. Self-concept had important direct…

  9. Managing Uncertainty in Water Infrastructure Design Using Info-gap Robustness

    Science.gov (United States)

    Irias, X.; Cicala, D.

    2013-12-01

    Info-gap theory, a tool for managing deep uncertainty, can be of tremendous value for design of water systems in areas of high seismic risk. Maintaining reliable water service in those areas is subject to significant uncertainties including uncertainty of seismic loading, unknown seismic performance of infrastructure, uncertain costs of innovative seismic-resistant construction, unknown costs to repair seismic damage, unknown societal impacts from downtime, and more. Practically every major earthquake that strikes a population center reveals additional knowledge gaps. In situations of such deep uncertainty, info-gap can offer advantages over traditional approaches, whether deterministic approaches that use empirical safety factors to address the uncertainties involved, or probabilistic methods that attempt to characterize various stochastic properties and target a compromise between cost and reliability. The reason is that in situations of deep uncertainty, it may not be clear what safety factor would be reasonable, or even if any safety factor is sufficient to address the uncertainties, and we may lack data to characterize the situation probabilistically. Info-gap is a tool that recognizes up front that our best projection of the future may be wrong. Thus, rather than seeking a solution that is optimal for that projection, info-gap seeks a solution that works reasonably well for all plausible conditions. In other words, info-gap seeks solutions that are robust in the face of uncertainty. Info-gap has been used successfully across a wide range of disciplines including climate change science, project management, and structural design. EBMUD is currently using info-gap to help it gain insight into possible solutions for providing reliable water service to an island community within its service area. The island, containing about 75,000 customers, is particularly vulnerable to water supply disruption from earthquakes, since it has negligible water storage and is

  10. Assessment of the terrestrial water balance using the global water availability and use model WaterGAP - status and challenges

    Science.gov (United States)

    Müller Schmied, Hannes; Döll, Petra

    2017-04-01

    The estimation of the World's water resources has a long tradition and numerous methods for quantification exists. The resulting numbers vary significantly, leaving room for improvement. Since some decades, global hydrological models (GHMs) are being used for large scale water budget assessments. GHMs are designed to represent the macro-scale hydrological processes and many of those models include human water management, e.g. irrigation or reservoir operation, making them currently the first choice for global scale assessments of the terrestrial water balance within the Anthropocene. The Water - Global Assessment and Prognosis (WaterGAP) is a model framework that comprises both the natural and human water dimension and is in development and application since the 1990s. In recent years, efforts were made to assess the sensitivity of water balance components to alternative climate forcing input data and, e.g., how this sensitivity is affected by WaterGAP's calibration scheme. This presentation shows the current best estimate of terrestrial water balance components as simulated with WaterGAP by 1) assessing global and continental water balance components for the climate period 1971-2000 and the IPCC reference period 1986-2005 for the most current WaterGAP version using a homogenized climate forcing data, 2) investigating variations of water balance components for a number of state-of-the-art climate forcing data and 3) discussing the benefit of the calibration approach for a better observation-data constrained global water budget. For the most current WaterGAP version 2.2b and a homogenized combination of the two WATCH Forcing Datasets, global scale (excluding Antarctica and Greenland) river discharge into oceans and inland sinks (Q) is assessed to be 40 000 km3 yr-1 for 1971-2000 and 39 200 km3 yr-1 for 1986-2005. Actual evapotranspiration (AET) is close to each other with around 70 600 (70 700) km3 yr-1 as well as water consumption with 1000 (1100) km3 yr-1. The

  11. Vulnerability Assessment of Water Supply Systems: Status, Gaps and Opportunities

    Science.gov (United States)

    Wheater, H. S.

    2015-12-01

    Conventional frameworks for assessing the impacts of climate change on water resource systems use cascades of climate and hydrological models to provide 'top-down' projections of future water availability, but these are subject to high uncertainty and are model and scenario-specific. Hence there has been recent interest in 'bottom-up' frameworks, which aim to evaluate system vulnerability to change in the context of possible future climate and/or hydrological conditions. Such vulnerability assessments are generic, and can be combined with updated information from top-down assessments as they become available. While some vulnerability methods use hydrological models to estimate water availability, fully bottom-up schemes have recently been proposed that directly map system vulnerability as a function of feasible changes in water supply characteristics. These use stochastic algorithms, based on reconstruction or reshuffling methods, by which multiple water supply realizations can be generated under feasible ranges of change in water supply conditions. The paper reports recent successes, and points to areas of future improvement. Advances in stochastic modeling and optimization can address some technical limitations in flow reconstruction, while various data mining and system identification techniques can provide possibilities to better condition realizations for consistency with top-down scenarios. Finally, we show that probabilistic and Bayesian frameworks together can provide a potential basis to combine information obtained from fully bottom-up analyses with projections available from climate and/or hydrological models in a fully integrated risk assessment framework for deep uncertainty.

  12. Desalination and water recycling by air gap membrane distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; Haan, de A.B.

    2006-01-01

    Membrane distillation (MD) is an emerging technology for desalination. Membrane distillation differs from other membrane technologies in that the driving force for desalination is the difference in vapour pressure of water across the membrane, rather than total pressure. The membranes for MD are

  13. Water recycling and desalination by air gap membrane distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; de Haan, A.B.

    2005-01-01

    Because salt and other small components are the most common compounds in wastewater from the process industry, desalination techniques are likely to be suitable as treatment processes in many cases. Although membrane distillation (MD) is a well-known technology for desalination and water treatment,

  14. Desalination and Water Recycling by Air Gap Membrane Distillation

    NARCIS (Netherlands)

    Meindersma, G.W.; Guijt, C.M.; de Haan, A.B.

    2006-01-01

    Membrane distillation (MD) is an emerging technology for desalination. Membrane distillation differs from other membrane technologies in that the driving force for desalination is the difference in vapour pressure of water across the membrane, rather than total pressure. The membranes for MD are

  15. Storm Water Management Model (SWMM): Performance Review and Gap Analysis

    Science.gov (United States)

    The Storm Water Management Model (SWMM) is a widely used tool for urban drainage design and planning. Hundreds of peer-reviewed articles and conference proceedings have been written describing applications of SWMM. This review focused on collecting information on model performanc...

  16. Spatial distribution of water supply reliability and critical links of water supply to crucial water consumers under an earthquake

    International Nuclear Information System (INIS)

    Wang Yu; Au, S.-K.

    2009-01-01

    This paper describes a process to characterize spatial distribution of water supply reliability among various consumers in a water system and proposes methods to identify critical links of water supply to crucial water consumers under an earthquake. Probabilistic performance of water supply is reflected by the probability of satisfying consumers' water demand, Damage Consequence Index (DCI) and Upgrade Benefit Index (UBI). The process is illustrated using a hypothetical water supply system, where direct Monte Carlo simulation is used for estimating the performance indices. The reliability of water supply to consumers varies spatially, depending on their respective locations in the system and system configuration. The UBI is adopted as a primary index in the identification of critical links for crucial water consumers. A pipe with a relatively large damage probability is likely to have a relatively large UBI, and hence, to be a critical link. The concept of efficient frontier is employed to identify critical links of water supply to crucial water consumers. It is found that a group of links that have the largest UBI individually do not necessarily have the largest group UBI, or be the group of critical links

  17. Filling the Gap : Relationship Between the Serotonin-Transporter-Linked Polymorphic Region and Amygdala Activation

    NARCIS (Netherlands)

    Bastiaansen, Jojanneke A.; Servaas, Michelle N.; Marsman, Jan-Bernard; Ormel, Johan; Nolte, Ilja M.; Riese, Harriette; Aleman, Andre

    2014-01-01

    The alleged association between the serotonin-transporter-linked polymorphic region (5-HTTLPR) and amygdala activation forms a cornerstone of the common view that carrying the short allele of this polymorphism is a potential risk factor for affective disorders. The authors of a recent meta-analysis

  18. Filling the Gap : Relationship Between the Serotonin-Transporter-Linked Polymorphic Region and Amygdala Activation

    NARCIS (Netherlands)

    Bastiaansen, Jojanneke A.; Servaas, Michelle N.; Marsman, Jan-Bernard; Ormel, Johan; Nolte, Ilja M.; Riese, Harriette; Aleman, Andre

    The alleged association between the serotonin-transporter-linked polymorphic region (5-HTTLPR) and amygdala activation forms a cornerstone of the common view that carrying the short allele of this polymorphism is a potential risk factor for affective disorders. The authors of a recent meta-analysis

  19. A vital link: water and vegetation in the Anthropocene

    Directory of Open Access Journals (Sweden)

    D. Gerten

    2013-10-01

    Full Text Available This paper argues that the interplay of water, carbon and vegetation dynamics fundamentally links some global trends in the current and conceivable future Anthropocene, such as cropland expansion, freshwater use, and climate change and its impacts. Based on a review of recent literature including geographically explicit simulation studies with the process-based LPJmL global biosphere model, it demonstrates that the connectivity of water and vegetation dynamics is vital for water security, food security and (terrestrial ecosystem dynamics alike. The water limitation of net primary production of both natural and agricultural plants – already pronounced in many regions – is shown to increase in many places under projected climate change, though this development is partially offset by water-saving direct CO2 effects. Natural vegetation can to some degree adapt dynamically to higher water limitation, but agricultural crops usually require some form of active management to overcome it – among them irrigation, soil conservation and eventually shifts of cropland to areas that are less water-limited due to more favourable climatic conditions. While crucial to secure food production for a growing world population, such human interventions in water–vegetation systems have, as also shown, repercussions on the water cycle. Indeed, land use changes are shown to be the second-most important influence on the terrestrial water balance in recent times. Furthermore, climate change (warming and precipitation changes will in many regions increase irrigation demand and decrease water availability, impeding rainfed and irrigated food production (if not CO2 effects counterbalance this impact – which is unlikely at least in poorly managed systems. Drawing from these exemplary investigations, some research perspectives on how to further improve our knowledge of human–water–vegetation interactions in the Anthropocene are outlined.

  20. Heterogenous treatment of water gaps and control rods in core calculations

    International Nuclear Information System (INIS)

    Lindahl, S.Oe.

    1984-08-01

    The conventional fuel assembly homogenization process introduces errors in the gross power distribution of the order of 10%. A method to mitigate the homogenization error is proposed. The gaps in between the fuel pin domains, containing water, control rod blades, fuel channel shroud, etc, are described by their transmission and reflection properties while the fuel pin regions are represented by conventional, homogenized cross sections. A nodal equation, incorporating the gap transmission and reflection functions, is set up in a general form. By numerical testing on 2D core problems it is shown that the explicit gap treatment is capable of reducing the homogenization error by an order of magnitude. (author)

  1. The Work-family Field: Gaps and Missing Links as Opportunities for Future Research

    Directory of Open Access Journals (Sweden)

    Katherina Kuschel

    2017-10-01

    Full Text Available This review presents a synthesis and a critique of the development of the existing workfamily (WF literature during the last decade in order to highlight gaps and limitations in current research. The study revises 83 peer-reviewed articles, book chapters and conference presentations (2004-2014 related to WF in economics, management and psychology disciplines, and classifies the current research into three broad themes for future research paths: i definitions and theories; ii background and outcomes of wf conflict, balance and enrichment; and iii methodological gaps. Advances have been made this decade on meta-analysis and the understanding of the positive side of WF interface. Future research opportunities in this field will include a deeper understanding of how to effectively cope with WF conflict, how to achieve WF enrichment, the use of different methods (qualitative, longitudinal and experimental studies on samples of new occupations, and how researchers could address methodological problems (causality, endogeneity, simultaneity, effect size, and self-selection bias to better handle the complexity of WF issues.

  2. A Linked Hydro-Economic Model to Examine the Effects of Water Policy on Rural Poverty

    Science.gov (United States)

    Maneta, M. P.; Torres, M.; Vosti, S. A.; Wallender, W. W.; Howitt, R.; Rodrigues, L. N.; Bassoi, L. H.; Pfeiffer, L.; Young, J.

    2006-12-01

    The sustainable intensification of small-scale agriculture is a necessary condition for reducing rural poverty in developing countries. Increasing the amount of irrigated cropland and the economic efficiency of irrigation are two key components of most intensification strategies. Improved access to water generally increases farm income but richer farmers use a disproportionate share of the available water, decreasing the chances of poor farmers to meet their water needs. Furthermore, water and poverty have strong spatial components that have so far been neglected in water planning. In that sense, too little is known about the short and long term hydrological effects, especially the externality effects of changes in on-farm water use and its implications to nearby farmers. To address this gap in knowledge, a spatially distributed and transient description of changes in surface and groundwater allocation under different agricultural management scenarios is needed. We propose a hydro-economic model providing a realistic spatio-temporal description of the linkages between the economic and hydrologic subsystems. This hydro-economic model is composed of a basin-level 3D spatially distributed transient hydrologic model (MOD-HMS) and a farm-level, spatially distributed agricultural production model. Both models are explicitly linked through the boundary conditions of the hydrologic model. The linkage will account for the spatial and temporal impact of different crop mixes, irrigation techniques and groundwater pumpage on water availability at farm level to assess the effects of policy action on the hydro-economic components of the system.

  3. Linking water and carbon cycles through salinity observed from space

    Science.gov (United States)

    Xie, X.; Liu, W. T.

    2017-12-01

    The association of ocean surface salinity in global hydrological cycle and climate change has been traditionally studied through the examination of its tendency and advection as manifestation of ocean's heat and water fluxes with the atmosphere. The variability of surface heat and water fluxes are linked to top of atmosphere radiation, whose imbalance is the main cause of global warming. Besides the link of salinity to greenhouse warming through water balance, this study will focus on the effect of changing salinity on carbon dioxide flux between the ocean and the atmosphere. We have built statistical models to estimate the partial pressure of carbon dioxide (pCO2) and ocean acidification (in terms of total alkalinity and pH) using spacebased data. PCO2 is a critical parameter governing ocean as source and sink of the accumulated greenhouse gas in the atmosphere. The exchange also causes ocean acidification, which is detrimental to marine lives and ecology. Before we had sufficient spacebased salinity measurements coincident with in situ pCO2 measurement, we trained our statistical models to use satellite sea surface temperature and chlorophyll, with one model using salinity climatology and the other without. We found significant differences between the two models in regions of strong water input through river discharge and surface water flux. The pCO2 output follows the seasonal salinity advection of the Amazon outflow. The seasonal salinity advection between Bay of Bengal and Arabian Sea are followed by change of pCO2 and total alkalinity. At shorter time scales, the signatures of rain associated with intraseasonal organized convection of summer monsoon can be detected. We have observed distribution agreement of among pCO2, surface salinity, and surface water flux for variation from a few days to a few years under the Pacific ITCZ; the agreement varies slightly with season and longitudes and the reason is under study.

  4. Jumpstarting post-conflict strategic water resources protection from a changing global perspective: gaps and prospects in Afghanistan.

    Science.gov (United States)

    Habib, H; Anceno, A J; Fiddes, J; Beekma, J; Ilyuschenko, M; Nitivattananon, V; Shipin, O V

    2013-11-15

    Notwithstanding ambiguities, long-term economic resurgence in Afghanistan amidst water insecurity exacerbated by climate change decisively requires a water protection strategy that will complement a multitude of agroindustrial and socioeconomic activities in an environmentally sustainable and climate resilient manner. In this paper, we begin with a perspective on institutions, legislation, and key issues in the water sector of Afghanistan. We then embark on linking the integrated water resources management (IWRM) and strategic environmental assessment (SEA) approaches as a novel framework for strategic water management and subsequently propose a strategy for post-conflict water protection based on the coalesced IWRM and SEA. Context relevant good practices worldwide are presented to provide empirical evidence for this approach whereas perceived opportunities and vulnerabilities in the Afghan context are discussed. Examination of post-conflict water sector initiatives in Afghanistan reveals the critical role of foreign assistance in both water infrastructure rehabilitation and modernization of the institutional aspect of water management. The introduction of IWRM as the basis for a progressive water sector strategy has been seen as a major milestone which is detrimentally matched by substantial deficiency in national capacity for implementation. Concurrently, the role of extra-national actors in relevant policy interventions has been considered catalytic despite criticisms of proposed regulations as being anachronistic to field realities. Therefore the view is maintained to practicable policies by accelerating policy learning in the country's water and environment sectors to encourage homegrown water strategy innovations. Demonstratively, mainstreaming IWRM-SEA coalescence will bridge institutional gaps for better feedback between local and national water stakeholders, providing a venue for improved delivery of water services to sustain post-conflict socioeconomic

  5. Healthier students are better learners: a missing link in school reforms to close the achievement gap.

    Science.gov (United States)

    Basch, Charles E

    2011-10-01

    This article provides an introduction to the October 2011 special issue of the Journal of School Health on "Healthier Students Are Better Learners." Literature was reviewed and synthesized to identify health problems affecting school-aged youth that are highly prevalent, disproportionately affect urban minority youth, directly and indirectly causally affect academic achievement, and can be feasibly and effectively addressed through school health programs and services. Based on these criteria, 7 educationally relevant health disparities were selected as strategic priorities to help close the achievement gap: (1) vision, (2) asthma, (3) teen pregnancy, (4) aggression and violence, (5) physical activity, (6) breakfast, and (7) inattention and hyperactivity. Research clearly shows that these health problems influence students' motivation and ability to learn. Disparities among urban minority youth are outlined, along with the causal pathways through which each adversely affects academic achievement, including sensory perceptions, cognition, school connectedness, absenteeism, and dropping out. Evidence-based approaches that schools can implement to address these problems are presented. These health problems and the causal pathways they influence have interactive and a synergistic effect, which is why they must be addressed collectively using a coordinated approach. No matter how well teachers are prepared to teach, no matter what accountability measures are put in place, no matter what governing structures are established for schools, educational progress will be profoundly limited if students are not motivated and able to learn. Particular health problems play a major role in limiting the motivation and ability to learn of urban minority youth. This is why reducing these disparities through a coordinated approach warrants validation as a cohesive school improvement initiative to close the achievement gap. Local, state, and national policies for implementing this

  6. Glacier surge mechanism based on linked cavity configuration of the basal water conduit system

    Science.gov (United States)

    Kamb, Barclay

    1987-08-01

    Based on observations of the 1982-1983 surge of Variegated Glacier, Alaska, a model of the surge mechanism is developed in terms of a transition from the normal tunnel configuration of the basal water conduit system to a linked cavity configuration that tends to restrict the flow of water, resulting in increased basal water pressures that cause rapid basal sliding. The linked cavity system consists of basal cavities formed by ice-bedrock separation (cavitation), ˜1 m high and ˜10 m in horizontal dimensions, widely scattered over the glacier bed, and hydraulically linked by narrow connections where separation is minimal (separation gap ≲ 0.1 m). The narrow connections, called orifices, control the water flow through the conduit system; by throttling the flow through the large cavities, the orifices keep the water flux transmitted by the basal water system at normal levels even though the total cavity cross-sectional area (˜200 m2) is much larger than that of a tunnel system (˜10 m2). A physical model of the linked cavity system is formulated in terms of the dimensions of the "typical" cavity and orifice and the numbers of these across the glacier width. The model concentrates on the detailed configuration of the typical orifice and its response to basal water pressure and basal sliding, which determines the water flux carried by the system under given conditions. Configurations are worked out for two idealized orifice types, step orifices that form in the lee of downglacier-facing bedrock steps, and wave orifices that form on the lee slopes of quasisinusoidal bedrock waves and are similar to transverse "N channels." The orifice configurations are obtained from the results of solutions of the basal-sliding-with-separation problem for an ice mass constituting of linear half-space of linear rheology, with nonlinearity introduced by making the viscosity stress-dependent on an intuitive basis. Modification of the orifice shapes by melting of the ice roof due to

  7. The ecogenetic link between demography and evolution: can we bridge the gap between theory and data?

    Science.gov (United States)

    Kokko, Hanna; López-Sepulcre, Andrés

    2007-09-01

    Calls to understand the links between ecology and evolution have been common for decades. Population dynamics, i.e. the demographic changes in populations, arise from life history decisions of individuals and thus are a product of selection, and selection, on the contrary, can be modified by such dynamical properties of the population as density and stability. It follows that generating predictions and testing them correctly requires considering this ecogenetic feedback loop whenever traits have demographic consequences, mediated via density dependence (or frequency dependence). This is not an easy challenge, and arguably theory has advanced at a greater pace than empirical research. However, theory would benefit from more interaction between related fields, as is evident in the many near-synonymous names that the ecogenetic loop has attracted. We also list encouraging examples where empiricists have shown feasible ways of addressing the question, ranging from advanced data analysis to experiments and comparative analyses of phylogenetic data.

  8. Properties of water leakage through concrete slabs with a parallel gap

    International Nuclear Information System (INIS)

    Shimooka, Kenji; Abe, Mikiya

    1988-10-01

    This paper describes the experimental results of water flow in concrete crack, in order to get the fundamental data on the barrier effect of the concrete material on the nuclide migration. Concrete slabs with a parallel gap, instead of the unidentified native cracks were used in the experiment and the water leakage through the certain gap was studied in detail. It is recognized that the water flow through cracks can be generally treated as a laminar flow, thus the theoretical equation derived from Navier-Stokes equation can be applied in the flow analysis. According to the theory, the amount of water flow through the crack is described to be proportional both to the third power of crack width and to the pressure gradient, and also to be inversely proportional to the coefficient of water viscosity. We have confirmed that the equation can be applied to the water flow through even 0.01 cm width gap in concrete by the experiments, measurement of the water flow under the conditions of constant head and gradually changing temperatures and also at the constant temperatures. (author)

  9. Linking economic water use, freshwater ecosystem impacts, and virtual water trade in a Great Lakes watershed

    Science.gov (United States)

    Mubako, S. T.; Ruddell, B. L.; Mayer, A. S.

    2013-12-01

    The impact of human water uses and economic pressures on freshwater ecosystems is of growing interest for water resource management worldwide. This case study for a water-rich watershed in the Great Lakes region links the economic pressures on water resources as revealed by virtual water trade balances to the nature of the economic water use and the associated impacts on the freshwater ecosystem. A water accounting framework that combines water consumption data and economic data from input output tables is applied to quantify localized virtual water imports and exports in the Kalamazoo watershed which comprises ten counties. Water using economic activities at the county level are conformed to watershed boundaries through land use-water use relationships. The counties are part of a region implementing the Michigan Water Withdrawal Assessment Process, including new regulatory approaches for adaptive water resources management under a riparian water rights framework. The results show that at local level, there exists considerable water use intensity and virtual water trade balance disparity among the counties and between water use sectors in this watershed. The watershed is a net virtual water importer, with some counties outsourcing nearly half of their water resource impacts, and some outsourcing nearly all water resource impacts. The largest virtual water imports are associated with agriculture, thermoelectric power generation and industry, while the bulk of the exports are associated with thermoelectric power generation and commercial activities. The methodology is applicable to various spatial levels ranging from the micro sub-watershed level to the macro Great Lakes watershed region, subject to the availability of reliable water use and economic data.

  10. Linking electricity and water models to assess electricity choices at water-relevant scales

    International Nuclear Information System (INIS)

    Sattler, S; Rogers, J; Macknick, J; Lopez, A; Yates, D; Flores-Lopez, F

    2012-01-01

    Hydrology/water management and electricity generation projections have been modeled separately, but there has been little effort in intentionally and explicitly linking the two sides of the water–energy nexus. This paper describes a platform for assessing power plant cooling water withdrawals and consumption under different electricity pathways at geographic and time scales appropriate for both electricity and hydrology/water management. This platform uses estimates of regional electricity generation by the Regional Energy Deployment System (ReEDS) as input to a hydrologic and water management model—the Water Evaluation and Planning (WEAP) system. In WEAP, this electricity use represents thermoelectric cooling water withdrawals and consumption within the broader, regional water resource context. Here we describe linking the electricity and water models, including translating electricity generation results from ReEDS-relevant geographies to the water-relevant geographies of WEAP. The result of this analysis is water use by the electric sector at the regional watershed level, which is used to examine the water resource implications of these electricity pathways. (letter)

  11. Bridging the climate-induced water gap in the twenty-first century: adaptation support based on water supply, demand, adaptation and financing.

    Science.gov (United States)

    Straatsma, Menno; Droogers, Peter; Brandsma, Jaïrus; Buytaert, Wouter; Karssenberg, Derek; Van Beek, Rens; Wada, Yoshihide; Sutanudjaja, Edwin; Vitolo, Claudia; Schmitz, Oliver; Meijer, Karen; Van Aalst, Maaike; Bierkens, Marc

    2014-05-01

    realistic combinations of a shared socio-economic pathways (SSPs) and RCPs. Our Water And Climate Adaptation Model (WatCAM) was used to compute the water gap based on reservoir capacity, water supply, and water demand. WatCam is based on the existing ModSim (Labadie, 2010) water allocation model, and facilitated the evaluation of nine technological and infrastructural adaptation measures to assess the investments needed to bridge the future water gap. Regional environmental and socio-economic effects of these investments, such as environmental flows or downstream effects, were evaluated. A scheme was developed to evaluate the strategies on robustness and flexibility under climate change and scenario uncertainty, and each measure was linked to possibilities for investment and financing mechanisms. The WatCAM is available as a web modeling service from www.water2invest.com, and enables user specified adaptation measures and the creation of an ensemble of water gap forecasts.

  12. 36 CFR 7.71 - Delaware Water Gap National Recreation Area.

    Science.gov (United States)

    2010-07-01

    ... THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.71 Delaware Water Gap National... route begins at the Smithfield Beach parking area and is in two loops. Loop One is a small trail... number of axles and wheels on a vehicle, regardless of load or weight, as follows: (i) Two-axle car, van...

  13. The Energy-Water Nexus: Managing the Links between Energy and Water for a Sustainable Future

    Science.gov (United States)

    Hussey, Karen; Petit, Carine

    2010-05-01

    Water and energy are both indispensable inputs to modern economies but currently both resources are under threat owing to the impacts of an ever-increasing population and associated demand, unsustainable practices in agriculture and manufacturing, and the implications of a changing climate. However, it is where water and energy rely on each other that pose the most complex challenges for policy-makers. Water is needed for mining coal, drilling oil, refining gasoline, and generating and distributing electricity; and, conversely, vast amounts of energy are needed to pump, transport, treat and distribute water, particularly in the production of potable water through the use of desalination plants and waste water treatment plants. Despite the links, and the urgency in both sectors for security of supply, in existing policy frameworks energy and water policies are developed largely in isolation from one another. Worse still, some policies designed to encourage alternative energy supplies give little thought to the resultant consequences on water resources, and, similarly, policies designed to secure water supplies pay little attention to the resultant consequences on energy use. The development of new technologies presents both opportunities and challenges for managing the energy-water nexus but a better understanding of the links between energy and water is essential in any attempt to formulate policies for more resilient and adaptable societies. The energy-water nexus must be adequately integrated into policy and decision-making or governments run the risk of contradicting their efforts, and therefore failing in their objectives, in both sectors. A series of COST Exploratory Workshops, drawing on on-going research in the energy-water nexus from a number of international teams, identified the implications of the energy-water nexus on the development of (i) energy policies (ii) water resource management policies and (iii) climate adaptation and mitigation policies. A

  14. Sustainable Water Infrastructure Asset Management: A Gap Analysis of Customer and Service Provider Perspectives

    Directory of Open Access Journals (Sweden)

    Sangjong Han

    2015-09-01

    Full Text Available The ultimate goal of urban water infrastructure asset management may be sustainable water supply with satisfaction for customers. In this work, we attempted to evaluate the gaps between the perspectives of customers and service providers in Korea’s water infrastructure asset management. To evaluate the customers’ perspective, a hierarchical questionnaire survey was conducted to estimate the weights of influence for six customer values and their attributes on Korean water utility management. To evaluate the service providers’ perspective, an AHP (Analytic Hierarchy Process analysis was performed to estimate the weights of influence for the customer values and their PIs (performance indicators. The gap analysis results show that customers place higher value on customer service satisfaction (emotion and information than do the service providers (managers, whereas the managers place more value on affordability than do the customers. The findings from this work imply that improving customer service is effective in satisfying the desirable water LOS (level of service for customers. Recommendations have also been provided for administrators and engineers to develop integrated decision-making systems that can reflect customer needs regarding the improvement of their water infrastructure asset management. The findings from this work may be helpful for the Korean government and water supply utilities in improving the sustainability of their water infrastructure asset management.

  15. Identifying data gaps and prioritizing restoration strategies for Fremont cottonwood using linked geomorphic and population models

    Science.gov (United States)

    Harper, E. B.; Stella, J. C.; Fremier, A. K.

    2009-12-01

    water for germination and adult tree growth. Our sensitivity analyses suggest that models of future scenarios should incorporate regional climate change projections because changes in temperature and the timing and volume of precipitation affects sensitive aspects of the system, including the timing of seed release and spring snowmelt runoff. Figure 1. The relative effects on model predictions of uncertainty around each parameter included in the patch-based population model for Fremont cottonwood.

  16. Water resources planning in a strategic context: Linking the water sector to the national economy

    Science.gov (United States)

    Rogers, Peter; Hurst, Christopher; Harshadeep, Nagaraja

    1993-07-01

    In many parts of the developing world investment in water resources takes a large proportion of the available public investment funds. As the conflicts for funds between the water and other sectors become more severe, the traditional ways of analyzing and planning water investments has to move away from project-by-project (or even a river basin-by-river basin) approaches to include the relationships of water investments to other sectors and to overall national development policies. Current approaches to water resources investments are too narrow. There is a need for ways to expand the strategic thinking of water sector managers. This paper develops a water resources planning methodology with the primary objective of giving insights into the linking of water sector investments and macroeconomic policies. The model optimizes the present value of investments for water resources development, while embedding a macroeconomic model into the framework to allow for an examination of the interactions between water investments, the growth in the agricultural sector, and the performance of the overall economy. A case study of Bangladesh is presented which shows how strategic thinking could lead to widely differing implications for water investments than would conventional water resources systems planning models.

  17. Scotland's Water Map: Understanding water sector links to support decision making for the Hydro Nation Agenda

    Science.gov (United States)

    Falconer, Ruth E.; Gilmour, Daniel; Duffy, Alison; Isaacs, John; Stojanovic, Vladeta; O'Keeffe, Juliette; Blackwood, David

    2015-04-01

    The value of Scotland's water and sewerage market is projected to grow to £1.24bn by 2016/17. Developing future opportunities must take place alongside maintaining current service provision; however the demand on water and waste water services is constantly evolving. An integrated approach to water management requires an understanding of complex interactions that exist between key actors in the sector to allow water management strategies to exploit inter-sectorial links. Successful integrated analysis of the water sector in Scotland will support management activities key to responding to the Hydro Nation themes of 1) Governance and international development 2) Environmental protection 3) Economic opportunities 4) Research development. In order to deliver on these objectives an approach is required to capture and communicate the scope and scale of the water sector and its interconnectedness. The methodology required to determine scope, scale and interconnectedness of water sector involved the identification and application of an appropriate range of techniques from the Information and Knowledge Management disciplines combined with the Information Visualisation field. Scope and scale of the water sector was identified by a desk based study and this data was visualized using a geographic map. Sector interconnectedness was determined by interviewing key actors. The interviews identified the stakeholders associated with information flows, and the purpose of the information transfer through Reporting/Managing (R/M), Influence and Information sharing (I) or Control (C) activities. Primary information flows were also scored with respect to importance against the 4 key Hydro Nation agenda themes. Many organisations were identified who interact within Scotland's water sector including the Scottish Government and Ministers, the Regulators (WICS, DWQR, SEPA), Scottish Water (core and non-core functions), plus many other stakeholders ranging from research institutions to

  18. Data gaps in evidence-based research on small water enterprises in developing countries.

    Science.gov (United States)

    Opryszko, Melissa C; Huang, Haiou; Soderlund, Kurt; Schwab, Kellogg J

    2009-12-01

    Small water enterprises (SWEs) are water delivery operations that predominantly provide water at the community level. SWEs operate beyond the reach of piped water systems, selling water to households throughout the world. Their ubiquity in the developing world and access to vulnerable populations suggests that these small-scale water vendors may prove valuable in improving potable water availability. This paper assesses the current literature on SWEs to evaluate previous studies and determine gaps in the evidence base. Piped systems and point-of-use products were not included in this assessment. Results indicate that SWES are active in urban, peri-urban and rural areas of Africa, Asia and Latin America. Benefits of SWEs include: no upfront connection fees; demand-driven and flexible to local conditions; and service to large populations without high costs of utility infrastructure. Disadvantages of SWEs include: higher charges for water per unit of volume compared with infrastructure-based utilities; lack of regulation; operation often outside legal structures; no water quality monitoring; increased potential for conflict with local utilities; and potential for extortion by local officials. No rigorous, evidence-based, peer-reviewed scientific studies that control for confounders examining the effectiveness of SWEs in providing potable water were identified.

  19. Understanding the drivers of the future water gap in the Indus-Ganges-Brahmaputra basins

    Science.gov (United States)

    Immerzeel, W. W.; Wijngaard, R. R.; Biemans, H.; Lutz, A. F.

    2017-12-01

    The Indus, Ganges, and Brahmaputra (IGB) river systems provide water resources for the agricultural, domestic and industrial sectors sustaining the lives of about 700 million people. The region is globally a hotspot for climate change as the headwaters of these rivers are fed by melt water from snow and glaciers, both strongly influenced by temperature change. In addition, the hydrology in the region is determined by the monsoon and its future dynamics as a results of climate change remains very uncertain. Simultaneously, the population is projected to grow rapidly over the coming decades, which in combination with strong economic developments, will likely result in a rapid increase in water demand. In this study we attempt to quantify the future water gap in the IGB and attribute this water gap to climate change and socio-economic growth. For the upstream mountainous parts of the basins we use the SPHY model, which is calibrated based on historical streamflow and glacier mass balance data and forced by the latest CMIP5 future climate model data for RCP4.5 and 8.5. Output of this model feeds into the downstream LPJmL model, which allows assessment of downstream climate change impacts and projected changes in water demand as a result of socio-economic developments. The LPJmL model is run for different combinations of RCPs and Shared Socio Economic Pathways (SSPs). Our results show that for the IGB as a whole climate change will increase water availability in the coming decades, due to an overall, albeit uncertain, increase in monsoon precipitation in combination with a sustained melt water supply from the upstream parts of the basins. However, irrespective of the SSP and RCP, the water demand as a result of socio-economic growth is expected to increase extremely fast in the near future and this is likely to be the main adaptation challenge for the IGB as far as water shortages are concerned. Our results also show that regional and temporal variation in the water gap

  20. Linking International Development Actors to Geophysical Infrastructure: Exploring an IRIS Community Role in Bridging a Communications Gap

    Science.gov (United States)

    Lerner-Lam, A.; Aster, R.; Beck, S.; Ekstrom, G.; Fisher, K.; Meltzer, A.; Nyblade, A.; Sandvol, E.; Willemann, R.

    2008-12-01

    Over the past quarter century, national investments in high-fidelity digital seismograph networks have resulted in a global infrastructure for real-time in situ earthquake monitoring. Many network operators adhere to community-developed standards, with the result that there are few technical impediments to data sharing and real-time information exchange. Two unanswered questions, however, are whether the existing models of international collaboration will ensure the stability and sustainability of global earthquake monitoring, and whether the participating institutions can work with international development agencies and non- governmental organizations in meeting linked development and natural hazard risk reduction goals. Since the 2004 Indian Ocean tsunami, many of these actors are enlarging their commitments to natural hazard risk reduction and building national technical capacities, among broader programs in poverty alleviation and adaptation to environmental stress. Despite this renewed commitment, international development organizations, with notable exceptions, have been relatively passive in discussions of how the existing earthquake monitoring infrastructure could be leveraged to support risk-reduction programs and meet sustainable development goals. At the same time, the international seismological community - comprising universities and government seismological surveys - has built research and education initiatives such as EarthScope, AfricaArray, and similar programs in China, Europe and South America, that use innovative instrumentation technologies and deployment strategies to enable new science and applications, and promote education and training in critical sectors. Can these developments be combined? Recognizing this communication or knowledge gap, the IRIS International Working Group (IWG) explores the link between the activities of IRIS Members using IRIS facilities and the missions of international development agencies, such as US AID, the World

  1. To trade or not to trade: Link prediction in the virtual water network

    Science.gov (United States)

    Tuninetti, Marta; Tamea, Stefania; Laio, Francesco; Ridolfi, Luca

    2017-12-01

    In the international trade network, links express the (temporary) presence of a commercial exchange of goods between any two countries. Given the dynamical behaviour of the trade network, where links are created and dismissed every year, predicting the link activation/deactivation is an open research question. Through the international trade network of agricultural goods, water resources are 'virtually' transferred from the country of production to the country of consumption. We propose a novel methodology for link prediction applied to the network of virtual water trade. Starting from the assumption of having links between any two countries, we estimate the associated virtual water flows by means of a gravity-law model using country and link characteristics as drivers. We consider the links with estimated flows higher than 1000 m3/year as active links, while the others as non-active links. Flows traded along estimated active links are then re-estimated using a similar but differently-calibrated gravity-law model. We were able to correctly model 84% of the existing links and 93% of the non-existing links in year 2011. It is worth to note that the predicted active links carry 99% of the global virtual water flow; hence, missed links are mainly those where a minimum volume of virtual water is exchanged. Results indicate that, over the period from 1986 to 2011, population, geographical distances between countries, and agricultural efficiency (through fertilizers use) are the major factors driving the link activation and deactivation. As opposed to other (network-based) models for link prediction, the proposed method is able to reconstruct the network architecture without any prior knowledge of the network topology, using only the nodes and links attributes; it thus represents a general method that can be applied to other networks such as food or value trade networks.

  2. Effects of Hydroxyl Radicals on Introduced Organisms of Ship's Ballast Water Based Micro-Gap Discharge

    International Nuclear Information System (INIS)

    Bai Mindong; Zhang Zhitao; Bai Mindi; Yang Bo; Bai Xiyao

    2007-01-01

    With the physical method of micro-gap gas discharge, OH· radicals were produced by the ionization of O 2 in air and H 2 O in the gaseous state, in order to explore more effective method to treat the ship's ballast water. The surface morphology of Al 2 O 3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al 2 O 3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved

  3. Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed

    Science.gov (United States)

    Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S.

    2013-01-01

    Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been proposed, but in general remain entirely hypothetical. For mineralized watersheds, a favored hypothesis is that falling water tables caused by declining recharge rates allow an increasing volume of sulfide-bearing rock to become exposed to air, thus oxygen. Here, we test the hypothesis that falling water tables are the primary cause of an increase in metals and SO4 (100-400%) observed since 1980 in the Upper Snake River (USR), Colorado. The USR drains an alpine watershed geologically and climatologically representative of many others in mineralized areas of the western U.S. Hydrologic and chemical data collected from 2005 to 2011 in a deep monitoring well (WP1) at the top of the USR watershed are utilized. During this period, both water table depths and groundwater SO4 concentrations have generally increased in the well. A numerical model was constructed using TOUGHREACT that simulates pyrite oxidation near WP1, including groundwater flow and oxygen transport in both saturated and unsaturated zones. The modeling suggests that a falling water table could produce an increase in metals and SO4 of a magnitude similar to that observed in the USR (up to 300%). Future water table declines may produce limited increases in sulfide weathering high in the watershed because of the water table dropping below the depth of oxygen penetration, but may continue to enhance sulfide weathering lower in the watershed where water tables are shallower. Advective air (oxygen) transport in the unsaturated zone caused by seasonally variable recharge and associated water table fluctuations was found to have little influence on pyrite

  4. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  5. Cross-linking of dermal sheep collagen using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Olde damink, L.H.H.; Olde Damink, L.H.H.; Dijkstra, Pieter J.; van Luyn, M.J.A.; van Wachem, P.B.; Nieuwenhuis, P.; Feijen, Jan

    1996-01-01

    A cross-linking method for collagen-based biomaterials was developed using the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride (EDC). Cross-linking using EDC involves the activation of carboxylic acid groups to give O-acylisourea groups, which form cross-links

  6. Cross-linking of wheat gluten using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Tropini, V.; Lens, J.P.; Mulder, W.J.; Silvestre, F.

    2000-01-01

    Wheat gluten was cross-linked using water-soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide HCl (EDC). To enhance cross-linking, N-hydroxysuccinimide (NHS) was added to the reaction mixture. The cross-linking efficiency was evaluated by the decrease in the amount of amino groups, the solubility

  7. Natural convection heat transfer of water in a horizontal circular gap

    Institute of Scientific and Technical Information of China (English)

    SU Guanghui; Kenichiro Sugiyama; WU Yingwei

    2007-01-01

    An experimental study on the natural convection heat transfer on a horizontal downward facing heated surface in a water gap was carried out under atmospheric pressure conditions. A total of 700 experimental data points were correlated using Rayleigh versus Nusselt number in various forms, based on different independent variables. The effects of different characteristic lengths and film temperatures were discussed. The results show that the buoyancy force acts as a resistance force for natural convecti on beat transfer ona downward facing horizontal heated surface in a confined space. For the estimation of the natural convection heat transfer under the present conditions, empirical correlations in which Nusselt number is expressed as a function of the Rayleigh number, or both Rayleigh and Prandtl numbers, may be used. When it is accurately predicted, the Nusselt number is expressed as a function of the Rayleigh and Prandtl numbers, as well as the gap width-to-heated surface diameter ratio; and uses the temperature difference between the heated surface and the ambient fluid in the definition of Rayleigh number. The characteristic length is the gap size and the film temperature is the average fluid temperature.

  8. Modeling of rotary movement of the articulating crane with increased gaps in the hinge joints of the links

    Directory of Open Access Journals (Sweden)

    Lagerev I.A.

    2016-06-01

    Full Text Available The article made computer simulation of dynamics of hydraulic articulating cranes with fully rotary motion for the case when the cylindrical hinges have an increased gap. Considered the use of special damping devices to reduce shock loads due to the presence of increased gaps. In previously developed software package KBCrane performed a series of calcu-lations made it possible to establish the relationship between the stiffness and damping devices the effectiveness of their use in varying the magnitude of the gap. In the case of the rotary movement of the articulating crane, a comparative analysis of work of joints of the connection node of the boom and lifting device with no gap and with high gaps. The features of the damping devices work joints and cushioning. Conclusions on positive and negative sides of the use of elastic damping devices.

  9. Effect of nitrogen and water deficit type on the yield gap between the potential and attainable wheat yield

    Directory of Open Access Journals (Sweden)

    Jiangang Liu

    2015-12-01

    Full Text Available Water deficit and N fertilizer are the two primary limiting factors for wheat yield in the North China plain, the most important winter wheat (Triticum aestivum L. production area in China. Analyzing the yield gap between the potential yield and the attainable yield can quantify the potential for increasing wheat production and exploring the limiting factors to yield gap in the high-yielding farming region of North China Plain. The Decision Support System for Agrotechnology Transfer (DSSAT model was used to identify methods to increase the grain yield and decrease the gap. In order to explore the impact of N and cultivars on wheat yield in the different drought types, the climate conditions during 1981 to 2011 growing seasons was categorized into low, moderate, and severe water deficit classes according to the anomaly percentage of the water deficit rate during the entire wheat growing season. There are differences (P < 0.0001 in the variations of the potential yields among three cultivars over 30 yr. For all three water deficit types, the more recent cultivars Jimai22 and Shijiazhuang8 had higher yields compared to the older 'Jinan17'. As the N fertilizer rate increased, the yield gap decreased more substantially during the low water deficit years because of the significant increase in attainable yield. Overall, the yield gaps were smaller with less water stress. Replacement of cultivars and appropriate N fertilizer application based on the forecasted drought types can narrow the yield gap effectively.

  10. Living waters: Linking cultural knowledge, ecosystem services, and wilderness

    Science.gov (United States)

    Linda Moon Stumpff

    2013-01-01

    American Indian tribes value pristine water sources that often originate in wilderness areas to support provisioning and cultural benefits. Based on interviews with four traditional leaders, this article focuses on the concept of living waters in ways that connect ecosystem service benefits to wilderness. Cultural knowledge connects indigenous water stewardship and...

  11. Band gaps and localization of surface water waves over large-scale sand waves with random fluctuations

    Science.gov (United States)

    Zhang, Yu; Li, Yan; Shao, Hao; Zhong, Yaozhao; Zhang, Sai; Zhao, Zongxi

    2012-06-01

    Band structure and wave localization are investigated for sea surface water waves over large-scale sand wave topography. Sand wave height, sand wave width, water depth, and water width between adjacent sand waves have significant impact on band gaps. Random fluctuations of sand wave height, sand wave width, and water depth induce water wave localization. However, random water width produces a perfect transmission tunnel of water waves at a certain frequency so that localization does not occur no matter how large a disorder level is applied. Together with theoretical results, the field experimental observations in the Taiwan Bank suggest band gap and wave localization as the physical mechanism of sea surface water wave propagating over natural large-scale sand waves.

  12. How to Limit Discrimination? Analyzing the Effects of Innovative Workplace Practices on Intra-Firm Gender Wage Gaps Using Linked Employer-Employee Data

    OpenAIRE

    Wolf, Elke; Heinze, Anja

    2007-01-01

    This paper provides a new approach to assess the impact of organisational changes fostering employee involvement, performance related pay schemes and other relevant trends in personnel policy on the gender wage gap. Our results indicate that innovative human resource practices tend to limit the wage differential between men and women. The innovation of this study is that we use linked employer-employee data to look at within-firm gender wage differentials. To investigate the theoretical hypot...

  13. Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon

    Science.gov (United States)

    2016-07-01

    was used to drive the transport and water quality kinetics for the simulation of 2007–2009. The sand berm, which controlled the opening/closure of...TECHNICAL REPORT 3015 July 2016 Calibration of Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei...Linked Hydrodynamic and Water Quality Model for Santa Margarita Lagoon Final Report Pei-Fang Wang Chuck Katz Ripan Barua SSC Pacific James

  14. Gap analysis between provisional diagnosis and final diagnosis in government and private teaching hospitals: A record-linked comparative study

    Directory of Open Access Journals (Sweden)

    Sudeshna Chatterjee

    2016-01-01

    Full Text Available Aims: 1. To identify the extent of clinical gaps at the context of knowledge, practice and systems. 2. To formulate necessary intervention measures towards bridging the gaps. Settings and Design: Comparative, cross-sectional and non-interventional study. Methods and Material: It is retrospective, record-based study conducted upon inpatients (n = 200 of major disciplines of two teaching hospitals. Major outcome variables were to observe the matching and un-matching of final and provisional diagnosis by using ICD-10 criteria. Statistical Analysis Used: Comparative analysis of specific and selective gaps were estimated in terms of percentage (%. Results: Pilot observation showed the existence of gaps between provisional and final diagnosis in both private and government institution. Both knowledge and skill gaps were evident in caregivers and gap in documentation was existent in medical records. Conclusions: The pilot data is may be an eye-opener to public and private governance systems for understanding and revising the process service planning and service delivery. Necessary intervention measures may be contemplated towards enhancing diagnostic skill of doctors for quality hospital care.

  15. Gap analysis between provisional diagnosis and final diagnosis in government and private teaching hospitals: A record-linked comparative study.

    Science.gov (United States)

    Chatterjee, Sudeshna; Ray, Krishnangshu; Das, Anup Kumar

    2016-01-01

    1. To identify the extent of clinical gaps at the context of knowledge, practice and systems. 2. To formulate necessary intervention measures towards bridging the gaps. Comparative, cross-sectional and non-interventional study. It is retrospective, record-based study conducted upon inpatients ( n = 200) of major disciplines of two teaching hospitals. Major outcome variables were to observe the matching and un-matching of final and provisional diagnosis by using ICD-10 criteria. Comparative analysis of specific and selective gaps were estimated in terms of percentage (%). Pilot observation showed the existence of gaps between provisional and final diagnosis in both private and government institution. Both knowledge and skill gaps were evident in caregivers and gap in documentation was existent in medical records. The pilot data is may be an eye-opener to public and private governance systems for understanding and revising the process service planning and service delivery. Necessary intervention measures may be contemplated towards enhancing diagnostic skill of doctors for quality hospital care.

  16. Linking ceragenins to water-treatment membranes to minimize biofouling.

    Energy Technology Data Exchange (ETDEWEB)

    Hibbs, Michael R.; Altman, Susan Jeanne; Feng, Yanshu (Brigham Young University, Provo, Utah); Savage, Paul B. (Brigham Young University, Provo, Utah); Pollard, Jacob (Brigham Young University, Provo, Utah); Branda, Steven S.; Goeres, Darla (Montana State University, Bozeman, MT); Buckingham-Meyer, Kelli (Montana State University, Bozeman, MT); Stafslien, Shane (North Dakota State University, Fargo, ND); Marry, Christopher; Jones, Howland D. T.; Lichtenberger, Alyssa; Kirk, Matthew F.; McGrath, Lucas K. (LMATA, Albuquerque, NM)

    2012-01-01

    Ceragenins were used to create biofouling resistant water-treatment membranes. Ceragenins are synthetically produced antimicrobial peptide mimics that display broad-spectrum bactericidal activity. While ceragenins have been used on bio-medical devices, use of ceragenins on water-treatment membranes is novel. Biofouling impacts membrane separation processes for many industrial applications such as desalination, waste-water treatment, oil and gas extraction, and power generation. Biofouling results in a loss of permeate flux and increase in energy use. Creation of biofouling resistant membranes will assist in creation of clean water with lower energy usage and energy with lower water usage. Five methods of attaching three different ceragenin molecules were conducted and tested. Biofouling reduction was observed in the majority of the tests, indicating the ceragenins are a viable solution to biofouling on water treatment membranes. Silane direct attachment appears to be the most promising attachment method if a high concentration of CSA-121a is used. Additional refinement of the attachment methods are needed in order to achieve our goal of several log-reduction in biofilm cell density without impacting the membrane flux. Concurrently, biofilm forming bacteria were isolated from source waters relevant for water treatment: wastewater, agricultural drainage, river water, seawater, and brackish groundwater. These isolates can be used for future testing of methods to control biofouling. Once isolated, the ability of the isolates to grow biofilms was tested with high-throughput multiwell methods. Based on these tests, the following species were selected for further testing in tube reactors and CDC reactors: Pseudomonas ssp. (wastewater, agricultural drainage, and Colorado River water), Nocardia coeliaca or Rhodococcus spp. (wastewater), Pseudomonas fluorescens and Hydrogenophaga palleronii (agricultural drainage), Sulfitobacter donghicola, Rhodococcus fascians, Rhodobacter

  17. Radioecological consequences of potential accident in Norwegian coastal waters. Uncertainties and knowledges gaps in methodology

    International Nuclear Information System (INIS)

    Iosjpe, M.; Reistad, O.; Brown, J.; Jaworska, A.; Amundsen, I.

    2007-01-01

    Complete text of publication follows. A potential accident involving the transport of spent nuclear fuel along the Norwegian coastline has been choosen for evaluation of a dose assessment methodology. The accident scenario assumes that the release the radioactivity takes place under water and that there is free exchange of water between the spent fuel and the sea. The inventory has been calculated using the ORIGEN programme. Radioecological consequences are provided by the NRPA compartment model which includes the processes of advection of radioactivity between compartments and water-sediment interactions. The contamination of biota is further calculated from the radionuclide concentrations in filtered seawater in the different water regions. Doses to man are calculated on the basis of radionuclide concentrations in marine organisms, water and sediment and dose conversion factors. Collective dose-rates to man, doses to the critical groups, concentration of radionuclides in biota/sea-foods and doses to marine organisms were calculated through the evaluation of radioecological consequences after accidents. Results of calculations indicate that concentrations of radionuclides for some marine organisms can exceed guideline levels. At the same time collective dose rates to man as well as doses to a critical group are not higher than guideline levels. Comparison of results from calculations with provisional benchmark values suggests that doses to biota are in most cases unlikely to be of concern. However, to some marine organisms can be much higher than the screening dose of 10 μGyh over long periods. It is apparent that water-sediment distribution coefficients and concentration factors constitute the main sources of uncertainties in the present case. It is important to note that knowledge gaps concerning the influence of relatively low dose to populations of marine organisms over long time periods (many generations) substantially constrain the accessor's ability to

  18. Water, energy, and climate change: what's the link? | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2013-01-31

    Jan 31, 2013 ... Related articles ... researchers have found changes in weather patterns and in the intensity of extreme weather events are resulting in the erosion of lo ... Water management and food security in vulnerable regions of China.

  19. Plasma treatment of polyethersulfone membrane for benzene removal from water by air gap membrane distillation.

    Science.gov (United States)

    Pedram, Sara; Mortaheb, Hamid Reza; Arefi-Khonsari, Farzaneh

    2018-01-01

    In order to obtain a durable cost-effective membrane for membrane distillation (MD) process, flat sheet polyethersulfone (PES) membranes were modified by an atmospheric pressure nonequilibrium plasma generated using a dielectric barrier discharge in a mixture of argon and hexamethyldisiloxane as the organosilicon precursor. The surface properties of the plasma-modified membranes were characterized by water contact angle (CA), liquid entry pressure, X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy. The water CA of the membrane was increased from 64° to 104° by depositing a Si(CH 3 )-rich thin layer. While the pristine PES membrane was not applicable in the MD process, the modified PES membrane could be applied for the first time in an air gap membrane distillation setup for the removal of benzene as a volatile organic compound from water. The experimental design using central composite design and response surface methodology was applied to study the effects of feed temperature, concentration, and flow rate as well as their binary interactions on the overall permeate flux and separation factor. The separation factor and permeation flux of the modified PES membrane at optimum conditions were comparable with those of commercial polytetrafluoroethylene membrane.

  20. Links between river water acidity, land use and hydrology

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, T.; Celebi, A.; Kloeve, B. [Oulu Univ. (Finland). Water Resources and Environmental Eng. Lab.], Email: tuomas.saarinen@oulu.fi

    2013-11-01

    In western Finland, acid leaching to watercourses is mainly due to drainage of acid sulphate (As) soils. This study examined how different land-use and land-cover types affect water acidity in the northwestern coastal region of Finland, which has abundant drained AS soils and peatlands. Sampling conducted in different hydrological conditions in studied river basins revealed two different catchment types: catchments dominated by drained forested peatlands and catchments used by agriculture. Low pH and high electric conductivity (EC) were typical in rivers affected by agriculture. In rivers dominated by forested peatlands and wetlands, EC was considerably lower. During spring and autumn high runoff events, water quality was poor and showed large spatial variation. Thus it is important to ensure that in river basin status assessment, sampling is carried out in different hydrological situations and in also water from some tributaries is sampled. (orig.)

  1. Linking land use with pesticides in Dutch surface waters.

    Science.gov (United States)

    Van't, Zelfde M T; Tamis, W L M; Vijver, M G; De Snoo, G R

    2012-01-01

    Compared with other European countries The Netherlands has a relatively high level of pesticide consumption, particularly in agriculture. Many of the compounds concerned end up in surface waters. Surface water quality is routinely monitored and numerous pesticides are found to be present in high concentrations, with various standards being regularly exceeded. Many standards-breaching pesticides exhibit regional patterns that can be traced back to land use. These patterns have been statistically analysed by correlating surface area per land use category with standards exceedance per pesticide, thereby identifying numerous significant correlations with respect to breaches of both the ecotoxicological standard (Maximum Tolerable Risk, MTR) and the drinking water standard. In the case of the MTR, greenhouse horticulture, floriculture and bulb-growing have the highest number as well as percentage of standard-breaching pesticides, despite these market segments being relatively small in terms of area cropped. Cereals, onions, vegetables, perennial border plants and pulses are also associated with many pesticides that exceed the drinking water standard. When a correction is made for cropped acreage, cereals and potatoes also prove to be a major contributor to monitoring sites where the MTR standard is exceeded. Over the period 1998-2006 the land-use categories with the most and highest percentage of standards-exceeding pesticides (greenhouse horticulture, bulb-growing and flower cultivation) showed an increase in the percentage of standards-exceeding compounds.

  2. Cassava productivity linked to potassium's influence on water use efficiency

    NARCIS (Netherlands)

    Ezui, K.S.; Franke, A.C.; Leffelaar, P.A.; Giller, K.E.

    2017-01-01

    This paper presents the results of field studies conducted in Togo (Djakakope and Sevekpota) to assess the effect of potassium (K) on cassava yield, water use efficiency (WUE) and transpiration as affected by nitrogen (N) and phosphorus (P) availability under rainfed conditions. It was shown that an

  3. Exergy Analysis of Air-Gap Membrane Distillation Systems for Water Purification Applications

    Directory of Open Access Journals (Sweden)

    Daniel Woldemariam

    2017-03-01

    Full Text Available Exergy analyses are essential tools for the performance evaluation of water desalination and other separation systems, including those featuring membrane distillation (MD. One of the challenges in the commercialization of MD technologies is its substantial heat demand, especially for large scale applications. Identifying such heat flows in the system plays a crucial role in pinpointing the heat loss and thermal integration potential by the help of exergy analysis. This study presents an exergetic evaluation of air-gap membrane distillation (AGMD systems at a laboratory and pilot scale. A series of experiments were conducted to obtain thermodynamic data for the water streams included in the calculations. Exergy efficiency and destruction for two different types of flat-plate AGMD were analyzed for a range of feed and coolant temperatures. The bench scale AGMD system incorporating condensation plate with more favorable heat conductivity contributed to improved performance parameters including permeate flux, specific heat demand, and exergy efficiency. For both types of AGMD systems, the contributions of the major components involved in exergy destruction were identified. The result suggested that the MD modules caused the highest fraction of destructions followed by re-concentrating tanks.

  4. Water linked 3D coordination polymers: Syntheses, structures and applications

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Suryabhan, E-mail: sbs.bhu@gmail.com; Bhim, Anupam

    2016-12-15

    Three new coordination polymers (CPs) based on Cd and Pb, [Cd(OBA)(μ-H{sub 2}O)(H{sub 2}O)]{sub n}1, [Pb(OBA)(μ-H{sub 2}O)]{sub n}2 [where OBA=4,4’-Oxybis(benzoate)] and [Pb(SDBA)(H{sub 2}O)]{sub n}.1/4DMF 3 (SDBA=4,4’-Sulfonyldibenzoate), have been synthesized and characterized. The single crystal structural studies reveal that CPs 1 and 2 have three dimensional structure. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. Compound 3 has a supramolecular 3D structure involving water molecule and hydrogen bonds. A structural transformation is observed when 3 was heated at 100 °C or kept in methanol, forming [Pb(SDBA)]{sub n}4. Compound 4 is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH{sub 4} at room temperature. Luminescence studies revealed that all CPs could be an effective sensor for nitroaromatic explosives. - Graphical abstract: Three new CPs based on Cd and Pb, have been synthesized and characterized. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. One of the CP is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol. Luminescence studies shown that all CPs could be an effective sensor for nitroaromatic explosives. - Highlights: • Three new CPs based on Cd and Pb, have been synthesized and characterized. • A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. • One of the CP is used as supporting matrix for palladium nanoparticles, PdNPs@4. • Luminescence studies shown that all CPs could be an effective sensor for nitroaromatic explosives.

  5. The properties of water in swollen cross-linked polystyrene sulfo acids

    Science.gov (United States)

    Gagarin, A. N.; Tokmachev, M. G.; Kovaleva, S. S.; Ferapontov, N. B.

    2008-11-01

    The properties of water in polystyrene sulfo acid gels with various cross-linking degrees were studied by optical volumetry and dynamic desorption porosimetry. The isotherms of water desorption obtained by dynamic desorption porosimetry coincided with isopiestic isotherms, which allowed this method to be recommended for the determination of the amount of water in polymer gels. Joint optical volumetry and dynamic desorption porosimetry studies showed that the interphase boundary in the cross-liked hydrophilic polymer-water system did not coincide with the visible gel boundary, because gels were two-phase systems, which contained water of two types, “free” and “bound.” The influence of the degree of polymer cross-linking on the amounts and properties of water of the two types was studied. It was shown that constants of water distribution in the polymer could be calculated from the dynamic desorption porosimetry data.

  6. Water linked 3D coordination polymers: Syntheses, structures and applications

    Science.gov (United States)

    Singh, Suryabhan; Bhim, Anupam

    2016-12-01

    Three new coordination polymers (CPs) based on Cd and Pb, [Cd(OBA)(μ-H2O)(H2O)]n1, [Pb(OBA)(μ-H2O)]n2 [where OBA=4,4'-Oxybis(benzoate)] and [Pb(SDBA)(H2O)]n.1/4DMF 3 (SDBA=4,4'-Sulfonyldibenzoate), have been synthesized and characterized. The single crystal structural studies reveal that CPs 1 and 2 have three dimensional structure. A water molecule bridges two metal centres which appears to the responsible for the dimensionality increase from 2D to 3D. Compound 3 has a supramolecular 3D structure involving water molecule and hydrogen bonds. A structural transformation is observed when 3 was heated at 100 °C or kept in methanol, forming [Pb(SDBA)]n4. Compound 4 is used as supporting matrix for palladium nanoparticles, PdNPs@4. The PdNPs@4 exhibits good catalytic activity toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4 at room temperature. Luminescence studies revealed that all CPs could be an effective sensor for nitroaromatic explosives.

  7. Measuring CO 2 and N 2 O Mass Transfer into GAP-1 CO 2 –Capture Solvents at Varied Water Loadings

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Zwoster, Andy; Zheng, Feng; Perry, Robert J.; Wood, Benjamin R.; Spiry, Irina; Freeman, Charles J.; Heldebrant, David J.

    2017-04-12

    This paper investigates the CO2 and N2 O absorption behavior in the water-lean gamma amino propyl (GAP)-1/TEG solvent system using a wetted-wall contactor. Testing was performed on a blend of GAP-1 aminosilicone in triethylene glycol at varied water loadings in the solvent. Measurements were made with CO2 and N2 O at representative lean (0.04 mol CO2/mol alkalinity), middle (0.13 mol CO2 /mol alkalinity) and rich (0.46 mol CO2 /mol alkalinity) solvent loadings at 0, 5, 10 and 15 wt% water loadings at 40, 60 and 80C° and N2 O at (0.08-0.09 mol CO2 /mol alkalinity) at 5 wt% water at 40, 60 and 80C°. CO2 flux was found to be non-linear with respect to log mean pressure driving force (LMPD). Liquid-film mass transfer coefficients (k'g) were calculated by subtracting the gas film resistance (determined from a correlation from literature) from the overall mass transfer measurement. The resulting k'g values for CO2 and N2 O in GAP-1/TEG mixtures were found to be higher than that of 5M aqueous monoethanolamine under comparable driving force albeit at higher solvent viscosities. The k'g values for CO2 were also found to decrease with increasing solvent water content and increase with a decrease in temperature. These observations indicate that mass transfer of CO2 in GAP-1/TEG is linked to the physical solubility of CO2 , which is higher in organic solvents compared to water. This paper expands on the understanding of the unique mass transfer behavior and kinetics of CO2 capture in water-lean solvents.

  8. Bridging "The Gap"--Linking Workplace-Based and University-Based Learning in Preschool Teacher Education in Sweden

    Science.gov (United States)

    Karlsson Lohmander, Maelis

    2015-01-01

    Professional experience in preschool settings comprises an important part of the education of preschool teachers. During their placements, students are expected to link theory to practice, to integrate university-based knowledge with workplace-based knowledge and skills essential for their future profession. They often refer to a perceived gap…

  9. Linking the effects of land use change with water quality and discharge :an integrated approach

    OpenAIRE

    Fauss, Lynn Michael

    1992-01-01

    Hydrologic and water-quality equilibria are greatly affected by changing land use. This study presents a methodology that integrates the use of remote sensing, geographical information systems (GIS) and water-quality modeling. Archived aerial photography proved to be a valuable source of historical land use data. GIS technology was used to compile and analyze spatial data. A comprehensive watershed model was used to link the effects of land use change to water quali...

  10. What drives the gender gap in STEM? The SAGA Science, Technology and Innovation Gender Objectives List (STI GOL) as a new approach to linking indicators to STI policies

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, E.; Schaaper, M.; Bello, A.

    2016-07-01

    There is a large imbalance in the participation of women in Science, Technology, Engineering and Mathematics (STEM) fields across all of Latin American countries despite the fact that the region has one of the highest proportions of female researchers worldwide (44% according to UIS statistics). Female researchers face persisting institutional and cultural barriers, which limit the development of their careers and constrains their access to decision-making positions. In this framework, UNESCO has launched the STEM and Gender Advancement (SAGA) project, which has for objective to address the gender gap in STEM fields in all countries at all levels of education and research as well as to promote women’s participation in science. SAGA is a global UNESCO project with the support of the Swedish Government through the Swedish International Development Cooperation Agency (Sida). One of the outcomes of this project is the SAGA Science, Technology and Innovation Gender Objectives List (STI GOL), which is an innovative tool that aids in the identification of gaps in the policy mix. Additionally, the STI GOL configures the conceptual backbone of the SAGA project, by linking gender equality STI policy instruments with indicators. By using the STI GOL, and identifying the gender gaps, policy-makers will be able to implement evidence-based policies in STEM fields. The SAGA STI GOL is a new and innovative way of contributing to the development of effective gender sensitive policies in STI fields, both in education and in the workplace. Likewise, it enables the categorization of STI policies and instruments, with the objective of identifying gaps in the policy mix and aid in the creation and design of evidence-based public policies to promote gender equality. (Author)

  11. Large band gaps of water waves through two-dimensional periodic topography

    International Nuclear Information System (INIS)

    Yang Shaohua; Wu Fugen; Zhong Huilin; Zhong Lanhua

    2006-01-01

    In this Letter, the band structures and band gaps of liquid surface waves propagating over two-dimensional periodic topography was investigated by plane-waves expansion method. The periodic topography drilled by square hollows with square lattice was considered. And the effects of the filling fraction and the orientation of bottom-hollows on the band gaps are investigated in detail

  12. Closing the Energy Efficiency Gap: A study linking demographics with barriers to adopting energy efficiency measures in the home

    International Nuclear Information System (INIS)

    Pelenur, Marcos J.; Cruickshank, Heather J.

    2012-01-01

    This paper presents a study which linked demographic variables with barriers affecting the adoption of domestic energy efficiency measures in large UK cities. The aim was to better understand the ‘Energy Efficiency Gap’ and improve the effectiveness of future energy efficiency initiatives. The data for this study was collected from 198 general population interviews (1.5–10 min) carried out across multiple locations in Manchester and Cardiff. The demographic variables were statistically linked to the identified barriers using a modified chi-square test of association (first order Rao–Scott corrected to compensate for multiple response data), and the effect size was estimated with an odds-ratio test. The results revealed that strong associations exist between demographics and barriers, specifically for the following variables: sex; marital status; education level; type of dwelling; number of occupants in household; residence (rent/own); and location (Manchester/Cardiff). The results and recommendations were aimed at city policy makers, local councils, and members of the construction/retrofit industry who are all working to improve the energy efficiency of the domestic built environment. -- Highlights: ► 7 demographic variables linked to 8 barriers to adopting energy efficiency measures. ► A modified chi-square test for association was used (first order Rao–Scott corrected). ► Results revealed strong associations between most of the demographics and barriers. ► Data was collected from 198 interviews in the UK cities of Manchester and Cardiff. ► Specific recommendations are presented for regional policy makers and industry.

  13. Oligothiophene-Indandione-Linked Narrow-Band Gap Molecules: Impact of π-Conjugated Chain Length on Photovoltaic Performance.

    Science.gov (United States)

    Komiyama, Hideaki; To, Takahiro; Furukawa, Seiichi; Hidaka, Yu; Shin, Woong; Ichikawa, Takahiro; Arai, Ryota; Yasuda, Takuma

    2018-04-04

    Solution-processed organic solar cells (OSCs) based on narrow-band gap small molecules hold great promise as next-generation energy-converting devices. In this paper, we focus on a family of A-π-D-π-A-type small molecules, namely, BDT- nT-ID ( n = 1-4) oligomers, consisting of benzo[1,2- b:4,5- b']dithiophene (BDT) as the central electron-donating (D) core, 1,3-indandione (ID) as the terminal electron-accepting (A) units, and two regioregular oligo(3-hexylthiophene)s ( nT) with different numbers of thiophene rings as the π-bridging units, and elucidate their structure-property-function relationships. The effects of the length of the π-bridging nT units on the optical absorption, thermal behavior, morphology, hole mobility, and OSC performance were systematically investigated. All oligomers exhibited broad and intense visible photoabsorption in the 400-700 nm range. The photovoltaic performances of bulk heterojunction OSCs based on BDT- nT-IDs as donors and a fullerene derivative as an acceptor were studied. Among these oligomers, BDT-2T-ID, incorporating bithiophene as the π-bridging units, showed better photovoltaic performance with a maximum power conversion efficiency as high as 6.9% under AM 1.5G illumination without using solvent additives or postdeposition treatments. These favorable properties originated from the well-developed interpenetrating network morphology of BDT-2T-ID, with larger domain sizes in the photoactive layer. Even though all oligomers have the same A-D-A main backbone, structural modulation of the π-bridging nT length was found to impact their self-organization and nanostructure formation in the solid state, as well as the corresponding OSC device performance.

  14. Material gap membrane distillation: A new design for water vapor flux enhancement

    KAUST Repository

    Francis, Lijo; Ghaffour, NorEddine; Alsaadi, Ahmad Salem; Amy, Gary L.

    2013-01-01

    A new module design for membrane distillation, namely material gap membrane distillation (MGMD), for seawater desalination has been proposed and successfully tested. It has been observed that employing appropriate materials between the membrane

  15. Advances in the ROBLINKS project on long-range shallow-water robust acoustic communciation links

    NARCIS (Netherlands)

    Gijzen, M.B. van; Walree, P.A. van; Cano, D.; Passerieux, J-M.; Waldhorst, A.; Weber, R.

    2000-01-01

    Within the ROBLINKS project waveforms and algorithms have been developed to establish robust underwater acoustic communication links with high data rates in shallow water. To evaluate the signalling schemes, a wide range of experiments has been performed during a sea trial that has been held in May

  16. Aggregating land use quantity and intensity to link water quality in upper catchment of Miyun Reservoir

    Science.gov (United States)

    Xu, E.

    2015-12-01

    Land use is closely related to hydrological and biochemical processes influencing the water quality. Quantifying relationship between both of them can help effectively manage land use to improve water quality. Previous studies majorly utilized land use quantity as an indicator to link water quality parameters, which lacked an insight to the influence of land use intensity. Taking upper catchment of Miyun Reservoir as a case study, we proposed a method of aggregating land use quantity and intensity to build a new land use indicator and investigated its explanation empower on water quality. Six nutrient concentrations from 52 sub-watersheds covering the whole catchment were used to characterize spatial distributions of water eutrophication. Based on spatial techniques and empirical conversion coefficients, combined remote sensing with socio-economic statistical data, land use intensity was measured and mapped visually. Then the new land use indicator was calculated and linked to nutrient concentrations by Pearson correlation coefficients. Results demonstrated that our new land use indicator incorporating intensity information can quantify the potential different nutrients exporting abilities from land uses. Comparing to traditional indicators only characterized by land use quantity, most Pearson correlation coefficients between new indicator and water nutrient concentrations increased. New information enhanced the explanatory power of land use on water nutrient concentrations. Then it can help better understand the impact of land use on water quality and guide land use management for supporting decision making.

  17. Linking poverty levels to water resource use and conflicts in rural Tanzania

    Science.gov (United States)

    Madulu, Ndalahwa F.

    Water scarcity is an important environmental constraint to development. Water availability is closely linked to human welfare and health by affecting nutrition status and quantity of drinking water especially for the poor. It has impacts on household labour because of the time and energy spent in obtaining it. These problems are more keenly felt among the poor households and in the agricultural subsistence economy. In many areas, the demand for water has been increasing due to rapid population growth, economic development, and climatic change. Water scarcity also stimulates social conflicts between various water users: individuals, communities, industries, livestock, wildlife, agriculture etc. Consequently, local communities have evolved strategies for coping with water stress and drought. These strategies include use of various sources of water, inaction to strict bye-laws regarding the use of water, crop diversification, wage labour, and possibly seasonal migration. The available strategies are likely to vary from one area to another. Some of these actions have measurable longterm demographic consequences, particularly if water stress is severe or repetitive. Although most governments and donor organizations often put much emphasis on the provision of water for drinking purposes, there is clear evidence that the supply of water for other uses has equal importance especially among rural communities. This observation suggests that putting too much emphasis on drinking water needs, addresses a rather insignificant part of the problem of water resources and biases the range of solutions which are likely to be proposed for perceived shortages. The presence of other water uses necessitates the provision of multi-purpose water sources that can serve a number of contrasting functions. This demand-responsive approach can enable the local communities and the poor households to choose the type of services they require on the basis of perceived needs and their ability to

  18. Exploring the link between meteorological drought and streamflow to inform water resource management

    Science.gov (United States)

    Lennard, Amy; Macdonald, Neil; Hooke, Janet

    2015-04-01

    Drought indicators are an under-used metric in UK drought management. Standardised drought indicators offer a potential monitoring and management tool for operational water resource management. However, the use of these metrics needs further investigation. This work uses statistical analysis of the climatological drought signal based on meteorological drought indicators and observed streamflow data to explore the link between meteorological drought and hydrological drought to inform water resource management for a single water resource region. The region, covering 21,000 km2 of the English Midlands and central Wales, includes a variety of landscapes and climatological conditions. Analysis of the links between meteorological drought and hydrological drought performed using streamflow data from 'natural' catchments indicates a close positive relationship between meteorological drought indicators and streamflow, enhancing confidence in the application of drought indicators for monitoring and management. However, many of the catchments in the region are subject to modification through impoundments, abstractions and discharge. Therefore, it is beneficial to explore how climatological drought signal propagates into managed hydrological systems. Using a longitudinal study of catchments and sub-catchments that include natural and modified river reaches the relationship between meteorological and hydrological drought is explored. Initial statistical analysis of meteorological drought indicators and streamflow data from modified catchments shows a significantly weakened statistical relationship and reveals how anthropogenic activities may alter hydrological drought characteristics in modified catchments. Exploring how meteorological drought indicators link to streamflow across the water supply region helps build an understanding of their utility for operational water resource management.

  19. Retrieval Accuracy Assessment with Gap Detection for Case 2 Waters Chla Algorithms

    Science.gov (United States)

    Salem, S. I.; Higa, H.; Kim, H.; Oki, K.; Oki, T.

    2016-12-01

    Inland lakes and coastal regions types of Case 2 Waters should be continuously and accurately monitored as the former contain 90% of the global liquid freshwater storage, while the latter provide most of the dissolved organic carbon (DOC) which is an important link in the global carbon cycle. The optical properties of Case 2 Waters are dominated by three optically active components: phytoplankton, non-algal particles (NAP) and color dissolved organic matter (CDOM). During the last three decades, researchers have proposed several algorithms to retrieve Chla concentration from the remote sensing reflectance. In this study, seven algorithms are assessed with various band combinations from multi and hyper-spectral data with linear, polynomial and power regression approaches. To evaluate the performance of the 43 algorithm combination sets, 500,000 remote sensing reflectance spectra are simulated with a wide range of concentrations for Chla, NAP and CDOM. The concentrations of Chla and NAP vary from 1-200 (mg m-3) and 1-200 (gm m-3), respectively, and the absorption of CDOM at 440 nm has the range of 0.1-10 (m-1). It is found that the three-band algorithm (665, 709 and 754 nm) with the quadratic polynomial (3b_665_QP) indicates the best overall performance. 3b_665_QP has the least error with a root mean square error (RMSE) of 0.2 (mg m-3) and a mean absolute relative error (MARE) of 0.7 %. The less accurate retrieval of Chla was obtained by the synthetic chlorophyll index algorithm with RMSE and MARE of 35.8 mg m-3 and 160.4 %, respectively. In general, Chla algorithms which incorporates 665 nm band or band tuning technique performs better than those with 680 nm. In addition, the retrieval accuracy of Chla algorithms with quadratic polynomial and power regression approaches are consistently better than the linear ones. By analyzing Chla versus NAP concentrations, the 3b_665_QP outperforms the other algorithms for all Chla concentrations and NAP concentrations above 40

  20. Linking Spatial Variations in Water Quality with Water and Land Management using Multivariate Techniques.

    Science.gov (United States)

    Wan, Yongshan; Qian, Yun; Migliaccio, Kati White; Li, Yuncong; Conrad, Cecilia

    2014-03-01

    Most studies using multivariate techniques for pollution source evaluation are conducted in free-flowing rivers with distinct point and nonpoint sources. This study expanded on previous research to a managed "canal" system discharging into the Indian River Lagoon, Florida, where water and land management is the single most important anthropogenic factor influencing water quality. Hydrometric and land use data of four drainage basins were uniquely integrated into the analysis of 25 yr of monthly water quality data collected at seven stations to determine the impact of water and land management on the spatial variability of water quality. Cluster analysis (CA) classified seven monitoring stations into four groups (CA groups). All water quality parameters identified by discriminant analysis showed distinct spatial patterns among the four CA groups. Two-step principal component analysis/factor analysis (PCA/FA) was conducted with (i) water quality data alone and (ii) water quality data in conjunction with rainfall, flow, and land use data. The results indicated that PCA/FA of water quality data alone was unable to identify factors associated with management activities. The addition of hydrometric and land use data into PCA/FA revealed close associations of nutrients and color with land management and storm-water retention in pasture and citrus lands; total suspended solids, turbidity, and NO + NO with flow and Lake Okeechobee releases; specific conductivity with supplemental irrigation supply; and dissolved O with wetland preservation. The practical implication emphasizes the importance of basin-specific land and water management for ongoing pollutant loading reduction and ecosystem restoration programs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Acanthamoeba Species Keratitis in a Soft Contact Lens Wearer Molecularly Linked to Well Water

    Directory of Open Access Journals (Sweden)

    Samira Mubareka

    2006-01-01

    Full Text Available Acanthamoeba species keratitis has been associated with soft contact lens wear. In the present report, an epidemiological link was established between the patient's isolate and well water from the home using molecular methods. To the authors' knowledge, this is the first case in Canada where such a link has been established. Primary care practitioners and specialists, including ophthalmologists and infectious diseases specialists, must maintain a high degree of clinical suspicion in soft contact lens wearers with keratitis unresponsive to conventional topical and systemic treatment.

  2. A linked hydrodynamic and water quality model for the Salton Sea

    Science.gov (United States)

    Chung, E.G.; Schladow, S.G.; Perez-Losada, J.; Robertson, Dale M.

    2008-01-01

    A linked hydrodynamic and water quality model was developed and applied to the Salton Sea. The hydrodynamic component is based on the one-dimensional numerical model, DLM. The water quality model is based on a new conceptual model for nutrient cycling in the Sea, and simulates temperature, total suspended sediment concentration, nutrient concentrations, including PO4-3, NO3-1 and NH4+1, DO concentration and chlorophyll a concentration as functions of depth and time. Existing water temperature data from 1997 were used to verify that the model could accurately represent the onset and breakup of thermal stratification. 1999 is the only year with a near-complete dataset for water quality variables for the Salton Sea. The linked hydrodynamic and water quality model was run for 1999, and by adjustment of rate coefficients and other water quality parameters, a good match with the data was obtained. In this article, the model is fully described and the model results for reductions in external phosphorus load on chlorophyll a distribution are presented. ?? 2008 Springer Science+Business Media B.V.

  3. Water-Food-Nutrition-Health Nexus: Linking Water to Improving Food, Nutrition and Health in Sub-Saharan Africa.

    Science.gov (United States)

    Mabhaudhi, Tafadzwanashe; Chibarabada, Tendai; Modi, Albert

    2016-01-06

    Whereas sub-Saharan Africa's (SSA) water scarcity, food, nutrition and health challenges are well-documented, efforts to address them have often been disconnected. Given that the region continues to be affected by poverty and food and nutrition insecurity at national and household levels, there is a need for a paradigm shift in order to effectively deliver on the twin challenges of food and nutrition security under conditions of water scarcity. There is a need to link water use in agriculture to achieve food and nutrition security outcomes for improved human health and well-being. Currently, there are no explicit linkages between water, agriculture, nutrition and health owing to uncoordinated efforts between agricultural and nutrition scientists. There is also a need to develop and promote the use of metrics that capture aspects of water, agriculture, food and nutrition. This review identified nutritional water productivity as a suitable index for measuring the impact of a water-food-nutrition-health nexus. Socio-economic factors are also considered as they influence food choices in rural communities. An argument for the need to utilise the region's agrobiodiversity for addressing dietary quality and diversity was established. It is concluded that a model for improving nutrition and health of poor rural communities based on the water-food-nutrition-health nexus is possible.

  4. Water-Food-Nutrition-Health Nexus: Linking Water to Improving Food, Nutrition and Health in Sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Tafadzwanashe Mabhaudhi

    2016-01-01

    Full Text Available Whereas sub-Saharan Africa’s (SSA water scarcity, food, nutrition and health challenges are well-documented, efforts to address them have often been disconnected. Given that the region continues to be affected by poverty and food and nutrition insecurity at national and household levels, there is a need for a paradigm shift in order to effectively deliver on the twin challenges of food and nutrition security under conditions of water scarcity. There is a need to link water use in agriculture to achieve food and nutrition security outcomes for improved human health and well-being. Currently, there are no explicit linkages between water, agriculture, nutrition and health owing to uncoordinated efforts between agricultural and nutrition scientists. There is also a need to develop and promote the use of metrics that capture aspects of water, agriculture, food and nutrition. This review identified nutritional water productivity as a suitable index for measuring the impact of a water-food-nutrition-health nexus. Socio-economic factors are also considered as they influence food choices in rural communities. An argument for the need to utilise the region’s agrobiodiversity for addressing dietary quality and diversity was established. It is concluded that a model for improving nutrition and health of poor rural communities based on the water-food-nutrition-health nexus is possible.

  5. Climate Change and European Water Bodies, a Review of Existing Gaps and Future Research Needs: Findings of the ClimateWater Project.

    Science.gov (United States)

    Garnier, Monica; Harper, David M; Blaskovicova, Lotta; Hancz, Gabriella; Janauer, Georg A; Jolánkai, Zsolt; Lanz, Eva; Lo Porto, Antonio; Mándoki, Monika; Pataki, Beata; Rahuel, Jean-Luc; Robinson, Victoria J; Stoate, Chris; Tóth, Eszter; Jolánkai, Géza

    2015-08-01

    There is general agreement among scientists that global temperatures are rising and will continue to increase in the future. It is also agreed that human activities are the most important causes of these climatic variations, and that water resources are already suffering and will continue to be greatly impaired as a consequence of these changes. In particular, it is probable that areas with limited water resources will expand and that an increase of global water demand will occur, estimated to be around 35-60% by 2025 as a consequence of population growth and the competing needs of water uses. This will cause a growing imbalance between water demand (including the needs of nature) and supply. This urgency demands that climate change impacts on water be evaluated in different sectors using a cross-cutting approach (Contestabile in Nat Clim Chang 3:11-12, 2013). These issues were examined by the EU FP7-funded Co-ordination and support action "ClimateWater" (bridging the gap between adaptation strategies of climate change impacts and European water policies). The project studied adaptation strategies to minimize the water-related consequences of climate change and assessed how these strategies should be taken into consideration by European policies. This article emphasizes that knowledge gaps still exist about the direct effects of climate change on water bodies and their indirect impacts on production areas that employ large amounts of water (e.g., agriculture). Some sectors, such as ecohydrology and alternative sewage treatment technologies, could represent a powerful tool to mitigate climate change impacts. Research needs in these still novel fields are summarized.

  6. Climate Change and European Water Bodies, a Review of Existing Gaps and Future Research Needs: Findings of the ClimateWater Project

    Science.gov (United States)

    Garnier, Monica; Harper, David M.; Blaskovicova, Lotta; Hancz, Gabriella; Janauer, Georg A.; Jolánkai, Zsolt; Lanz, Eva; Porto, Antonio Lo; Mándoki, Monika; Pataki, Beata; Rahuel, Jean-Luc; Robinson, Victoria J.; Stoate, Chris; Tóth, Eszter; Jolánkai, Géza

    2015-08-01

    There is general agreement among scientists that global temperatures are rising and will continue to increase in the future. It is also agreed that human activities are the most important causes of these climatic variations, and that water resources are already suffering and will continue to be greatly impaired as a consequence of these changes. In particular, it is probable that areas with limited water resources will expand and that an increase of global water demand will occur, estimated to be around 35-60 % by 2025 as a consequence of population growth and the competing needs of water uses. This will cause a growing imbalance between water demand (including the needs of nature) and supply. This urgency demands that climate change impacts on water be evaluated in different sectors using a cross-cutting approach (Contestabile in Nat Clim Chang 3:11-12, 2013). These issues were examined by the EU FP7-funded Co-ordination and support action "ClimateWater" (bridging the gap between adaptation strategies of climate change impacts and European water policies). The project studied adaptation strategies to minimize the water-related consequences of climate change and assessed how these strategies should be taken into consideration by European policies. This article emphasizes that knowledge gaps still exist about the direct effects of climate change on water bodies and their indirect impacts on production areas that employ large amounts of water (e.g., agriculture). Some sectors, such as ecohydrology and alternative sewage treatment technologies, could represent a powerful tool to mitigate climate change impacts. Research needs in these still novel fields are summarized.

  7. The `seafood gap' in the food-water nexus literature-issues surrounding freshwater use in seafood production chains

    Science.gov (United States)

    Gephart, Jessica A.; Troell, Max; Henriksson, Patrik J. G.; Beveridge, Malcolm C. M.; Verdegem, Marc; Metian, Marc; Mateos, Lara D.; Deutsch, Lisa

    2017-12-01

    Freshwater use for food production is projected to increase substantially in the coming decades with population growth, changing demographics, and shifting diets. Ensuring joint food-water security has prompted efforts to quantify freshwater use for different food products and production methods. However, few analyses quantify freshwater use for seafood production, and those that do use inconsistent water accounting. This inhibits water use comparisons among seafood products or between seafood and agricultural/livestock products. This 'seafood gap' in the food-water nexus literature will become increasingly problematic as seafood consumption is growing globally and aquaculture is one of the fastest growing animal food sectors in the world. Therefore, the present study 1) reviews freshwater use concepts as they relate to seafood production; 2) provides three cases to highlight the particular water use concerns for aquaculture, and; 3) outlines future directions to integrate seafood into the broader food-water nexus discussion. By revisiting water use concepts through a focus on seafood production systems, we highlight the key water use processes that should be considered for seafood production and offer a fresh perspective on the analysis of freshwater use in food systems more broadly.

  8. Error Analysis of Clay-Rock Water Content Estimation with Broadband High-Frequency Electromagnetic Sensors—Air Gap Effect

    Directory of Open Access Journals (Sweden)

    Thierry Bore

    2016-04-01

    Full Text Available Broadband electromagnetic frequency or time domain sensor techniques present high potential for quantitative water content monitoring in porous media. Prior to in situ application, the impact of the relationship between the broadband electromagnetic properties of the porous material (clay-rock and the water content on the frequency or time domain sensor response is required. For this purpose, dielectric properties of intact clay rock samples experimental determined in the frequency range from 1 MHz to 10 GHz were used as input data in 3-D numerical frequency domain finite element field calculations to model the one port broadband frequency or time domain transfer function for a three rods based sensor embedded in the clay-rock. The sensor response in terms of the reflection factor was analyzed in time domain with classical travel time analysis in combination with an empirical model according to Topp equation, as well as the theoretical Lichtenecker and Rother model (LRM to estimate the volumetric water content. The mixture equation considering the appropriate porosity of the investigated material provide a practical and efficient approach for water content estimation based on classical travel time analysis with the onset-method. The inflection method is not recommended for water content estimation in electrical dispersive and absorptive material. Moreover, the results clearly indicate that effects due to coupling of the sensor to the material cannot be neglected. Coupling problems caused by an air gap lead to dramatic effects on water content estimation, even for submillimeter gaps. Thus, the quantitative determination of the in situ water content requires careful sensor installation in order to reach a perfect probe clay rock coupling.

  9. Error Analysis of Clay-Rock Water Content Estimation with Broadband High-Frequency Electromagnetic Sensors—Air Gap Effect

    Science.gov (United States)

    Bore, Thierry; Wagner, Norman; Delepine Lesoille, Sylvie; Taillade, Frederic; Six, Gonzague; Daout, Franck; Placko, Dominique

    2016-01-01

    Broadband electromagnetic frequency or time domain sensor techniques present high potential for quantitative water content monitoring in porous media. Prior to in situ application, the impact of the relationship between the broadband electromagnetic properties of the porous material (clay-rock) and the water content on the frequency or time domain sensor response is required. For this purpose, dielectric properties of intact clay rock samples experimental determined in the frequency range from 1 MHz to 10 GHz were used as input data in 3-D numerical frequency domain finite element field calculations to model the one port broadband frequency or time domain transfer function for a three rods based sensor embedded in the clay-rock. The sensor response in terms of the reflection factor was analyzed in time domain with classical travel time analysis in combination with an empirical model according to Topp equation, as well as the theoretical Lichtenecker and Rother model (LRM) to estimate the volumetric water content. The mixture equation considering the appropriate porosity of the investigated material provide a practical and efficient approach for water content estimation based on classical travel time analysis with the onset-method. The inflection method is not recommended for water content estimation in electrical dispersive and absorptive material. Moreover, the results clearly indicate that effects due to coupling of the sensor to the material cannot be neglected. Coupling problems caused by an air gap lead to dramatic effects on water content estimation, even for submillimeter gaps. Thus, the quantitative determination of the in situ water content requires careful sensor installation in order to reach a perfect probe clay rock coupling. PMID:27096865

  10. Error Analysis of Clay-Rock Water Content Estimation with Broadband High-Frequency Electromagnetic Sensors--Air Gap Effect.

    Science.gov (United States)

    Bore, Thierry; Wagner, Norman; Lesoille, Sylvie Delepine; Taillade, Frederic; Six, Gonzague; Daout, Franck; Placko, Dominique

    2016-04-18

    Broadband electromagnetic frequency or time domain sensor techniques present high potential for quantitative water content monitoring in porous media. Prior to in situ application, the impact of the relationship between the broadband electromagnetic properties of the porous material (clay-rock) and the water content on the frequency or time domain sensor response is required. For this purpose, dielectric properties of intact clay rock samples experimental determined in the frequency range from 1 MHz to 10 GHz were used as input data in 3-D numerical frequency domain finite element field calculations to model the one port broadband frequency or time domain transfer function for a three rods based sensor embedded in the clay-rock. The sensor response in terms of the reflection factor was analyzed in time domain with classical travel time analysis in combination with an empirical model according to Topp equation, as well as the theoretical Lichtenecker and Rother model (LRM) to estimate the volumetric water content. The mixture equation considering the appropriate porosity of the investigated material provide a practical and efficient approach for water content estimation based on classical travel time analysis with the onset-method. The inflection method is not recommended for water content estimation in electrical dispersive and absorptive material. Moreover, the results clearly indicate that effects due to coupling of the sensor to the material cannot be neglected. Coupling problems caused by an air gap lead to dramatic effects on water content estimation, even for submillimeter gaps. Thus, the quantitative determination of the in situ water content requires careful sensor installation in order to reach a perfect probe clay rock coupling.

  11. Water Resource Management Mechanisms for Intrastate Violent Conflict Resolution: the Capacity Gap and What To Do About It.

    Science.gov (United States)

    Workman, M.; Veilleux, J. C.

    2014-12-01

    Violent conflict and issues surrounding available water resources are both global problems and are connected. Violent conflict is increasingly intrastate in nature and coupled with increased hydrological variability as a function of climate change, there will be increased pressures on water resource use. The majority of mechanisms designed to secure water resources are often based on the presence of a governance framework or another type of institutional capacity, such as offered through a supra- or sub-national organization like the United Nations or a river basin organization. However, institutional frameworks are not present or loose functionality during violent conflict. Therefore, it will likely be extremely difficult to secure water resources for a significant proportion of populations in Fragile and Conflict Affected States. However, the capacity in Organisation for Economic Co-operation and Development nations for the appropriate interventions to address this problem is reduced by an increasing reluctance to participate in interventionist operations following a decade of expeditionary warfighting mainly in Iraq and Afghanistan, and related defence cuts. Therefore, future interventions in violent conflict and securing water resources may be more indirect in nature. This paper assesses the state of understanding key areas in the present literature and highlights the gap of securing water resources during violent conflict in the absence of institutional capacity. There is a need to close this gap as a matter of urgency by formulating frameworks to assess the lack of institutional oversight / framework for water resources in areas where violent conflict is prevalent; developing inclusive resource management platforms through transparency and reconciliation mechanisms; and developing endogenous confidence-building measures and evaluate how these may be encouraged by exogenous initiatives including those facilitated by the international community. This effort

  12. Bridging Water Issue Knowledge Gaps between the General Public and Opinion Leaders

    Science.gov (United States)

    Lamm, Kevan W.; Lamm, Alexa J.; Carter, Hannah S.

    2015-01-01

    Global conflicts have rapidly made water the most contentious issue in the world today. Considering water drives health, industry, recreation, and the agricultural food system it is no surprise that it has become such a hot topic. As a result, the general public has an increased interest in water-focused policy; policy that can have a large impact…

  13. AFLP marker linked to water-stress-tolerant bulks in barley (Hordeum vulgare L.

    Directory of Open Access Journals (Sweden)

    A. Altinkut

    2003-01-01

    Full Text Available The amplified fragment length polymorphism (AFLP assay is an efficient method for the identification of molecular markers, useful in the improvement of numerous crop species. Bulked Segregant Analysis (BSA was used to identify AFLP markers associated with water-stress tolerance in barley, as this would permit rapid selection of water-stress tolerant genotypes in breeding programs. AFLP markers linked to water-stress tolerance was identified in two DNA pools (tolerant and sensitive, which were established using selected F2 individuals resulting from a cross between water-stress-tolerant and sensitive barley parental genotypes, based on their paraquat (PQ tolerance, leaf size, and relative water content (RWC. All these three traits were previously shown to be associated with water-stress tolerance in segregating F2 progeny of the barley cross used in a previous study. AFLP analysis was then performed on these DNA pools, using 40 primer pairs to detect AFLP fragments that are present/absent, respectively, in the two pools and their parental lines. One separate AFLP fragment, which was present in the tolerant parent and in the tolerant bulk, but absent in the sensitive parent and in the sensitive bulk, was identified. Polymorphism of the AFLP marker was tested among tolerant and sensitive F2 individuals. The presence of this marker that is associated with water-stress tolerance will greatly enhance selection for paraquat and water-stress tolerant genotypes in future breeding programs.

  14. Putting produced water to a useful purpose : regulatory gaps and other concerns

    International Nuclear Information System (INIS)

    Kwasniak, A.J.

    2006-01-01

    This presentation discussed issues related to produced water from oil and gas activities and its use and disposal in Alberta. The province is in danger of a water shortage, and studies have shown that runoff volumes in the South Saskatchewan River Basin (SSRB) are below average. A recent assessment of 33 river reaches in the SSRB has shown that 31 river reaches are approaching ecologically unacceptable values. Water produced from coalbed methane (CBM) activities will be only marginally saline or non-saline, and CBM activities are expected to increase in the region in order to supplement Alberta's dwindling natural gas supplies. Approximately 10 per cent of the CBM wells drilled in 2004 targeted seams that contained water. Approximately 50,000 more CBM wells will be drilled in Alberta in the next decade. While water conservation will help to address the situation, the re-use of produced water in processing technologies will help to reduce the impact of oil and gas activities in the province. However, regulatory difficulties may prevent produced water from being re-used. It is not currently known whether operators require a water rights permit to produce water. Regulatory obligations concerning damage to aquifers and water discharges are also unclear. The Water Act currently requires statutory authorizations for diversions of water. If the water is non-saline, then the operator is required to obtain a licence to divert produced water from its source. It was concluded that clear legislation is needed to determine if water can be re-used after it is brought to the surface. The introduction of an American-style beneficial rights use was recommended. refs., tabs., figs

  15. Linking xylem water storage with anatomical parameters in five temperate tree species.

    Science.gov (United States)

    Jupa, Radek; Plavcová, Lenka; Gloser, Vít; Jansen, Steven

    2016-06-01

    The release of water from storage compartments to the transpiration stream is an important functional mechanism that provides the buffering of sudden fluctuations in water potential. The ability of tissues to release water per change in water potential, referred to as hydraulic capacitance, is assumed to be associated with the anatomy of storage tissues. However, information about how specific anatomical parameters determine capacitance is limited. In this study, we measured sapwood capacitance (C) in terminal branches and roots of five temperate tree species (Fagus sylvatica L., Picea abies L., Quercus robur L., Robinia pseudoacacia L., Tilia cordata Mill.). Capacitance was calculated separately for water released mainly from capillary (CI; open vessels, tracheids, fibres, intercellular spaces and cracks) and elastic storage compartments (CII; living parenchyma cells), corresponding to two distinct phases of the moisture release curve. We found that C was generally higher in roots than branches, with CI being 3-11 times higher than CII Sapwood density and the ratio of dead to living xylem cells were most closely correlated with C In addition, the magnitude of CI was strongly correlated with fibre/tracheid lumen area, whereas CII was highly dependent on the thickness of axial parenchyma cell walls. Our results indicate that water released from capillary compartments predominates over water released from elastic storage in both branches and roots, suggesting the limited importance of parenchyma cells for water storage in juvenile xylem of temperate tree species. Contrary to intact organs, water released from open conduits in our small wood samples significantly increased CI at relatively high water potentials. Linking anatomical parameters with the hydraulic capacitance of a tissue contributes to a better understanding of water release mechanisms and their implications for plant hydraulics. © The Author 2016. Published by Oxford University Press. All rights

  16. The Joint Front Range Climate Change Vulnerability Study: Closing the Gap between Science and Water Management Decisions

    Science.gov (United States)

    Kaatz, L.; Yates, D.; Woodbury, M.

    2008-12-01

    There is increasing concern among metropolitan water providers in Colorado's Front Range about the possible impacts of global and regional climate changes on their future water supply. This is of particular worry given that recent studies indicate global warming may lead to unprecedented drought conditions in the Southwest U.S. (IPCC 2007). The City of Aurora, City of Boulder, Colorado Springs Utilities, Denver Water, City of Ft. Collins, and Northern Colorado Water Conservancy District, along with additional water agencies including the Colorado Water Conservation Board, the Water Research Foundation (formerly AwwaRF), and the NOAA-CIRES Western Water Assessment, have come together to participate in a study intended to provide the education, tools, and methodology necessary to examine possible effects of climate change on several common watersheds. The central objective of this project is to assess possible changes in the timing and volume of hydrologic runoff from selected climate change scenarios centered about the years 2040 and 2070. Two hydrologic models will be calibrated and implemented in the study for this purpose. The future temperature and precipitation scenarios used to generate corresponding future streamflow are based on regionally downscaled temperature and precipitation projections. The projected streamflow obtained by running varied sequences of temperature and precipitation through the hydrologic models, will be compared to historic streamflow to estimate the sensitivity of water supplies to climate change. This regional unified approach is intended to help Colorado water providers communicate with their customers and the media cohesively, by working with the same historic and projected hydrometeorological data, historic natural streamflow, and methodology. Lessons learned from this collaborative approach can be used to encourage and establish other regional efforts throughout the country. Furthermore, this study will set the stage for future

  17. Modeling of the water gap in BWR fuel elements using SCALE/TRITON; Modellierung des Wasserspalts bei SWR-BE mit SCALE/TRITON

    Energy Technology Data Exchange (ETDEWEB)

    Tittelbach, S.; Chernykh, M. [WTI Wissenschaftlich-Technische Ingenieurberatung GmbH, Juelich (Germany)

    2012-11-01

    The authors show that an adequate modeling of the water gap in BWR fuel element models using the code TRITON requires an explicit consideration of the Dancoff factors. The analysis of three modeling options reveals that considering the moderating effects of the water gap coolant for the peripheral fuel elements the resulting deviations of the U-235 and Pu-239 concentrations are significantly reduced. The increased temporal calculation efforts are justified with respect to the burnup credits for criticality safety analyses.

  18. Borax cross-linked guar gum hydrogels as potential adsorbents for water purification.

    Science.gov (United States)

    Thombare, Nandkishore; Jha, Usha; Mishra, Sumit; Siddiqui, M Z

    2017-07-15

    With the aim to explore new adsorbents for water purification, guar gum based hydrogels were synthesized by cross-linking with borax at different percentage. The cross-linking was confirmed through characterization by FTIR spectroscopy, SEM morphology, thermal studies and water absorption capacity. To examine the adsorption/absorption performance of different grades of hydrogels, their flocculation efficiency was studied in kaolin suspension at different pH by standard jar test procedure. The flocculation efficiency of the test materials was compared with the commercially used coagulant, alum and also residues of Al and K left in the treated water were comparatively studied. The synthesized hydrogels were also tested for their efficiency of removing Aniline Blue dye by UV-vis spectrophotometer study. The best grade hydrogel outperformed alum, at extremely low concentration and also showed dye removing efficiency up to 94%. The single step synthesized green products thus exhibited great potential as water purifying agents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Forest filled with gaps : effects of gap size on water and nutrient cycling in tropical rain forest : a study in Guyana

    NARCIS (Netherlands)

    Dam, O. van

    2001-01-01

    Guyana's forests are selectively logged and a forest management is desired that is economically sustainable and ecologically responsible. Canopy gaps, created by selective logging, induce changes to microclimatic and edaphic conditions. These changes influence the regeneration of the

  20. Dehydration of an ethanol/water azeotrope through alginate-DNA membranes cross-linked with metal ions by pervaporation.

    Science.gov (United States)

    Uragami, Tadashi; Banno, Masashi; Miyata, Takashi

    2015-12-10

    To obtain high dehydration membranes for an ethanol/water azeotrope, dried blend membranes prepared from mixtures of sodium alginate (Alg-Na) and sodium deoxyribonucleate (DNA-Na) were cross-linked by immersing in a methanol solution of CaCl2 or MaCl2. In the dehydration of an ethanol/water azeotropic mixture by pervaporation, the effects of immersion time in methanol solution of CaCl2 or MaCl2 on the permeation rate and water/ethanol selectivity through Alg-DNA/Ca(2+) and Alg-DNA/Mg(2+) cross-linked membranes were investigated. Alg-DNA/Mg(2+) cross-linked membrane immersed for 12h in methanol solution of MaCl2 exhibited the highest water/ethanol selectivity. This results from depressed swelling of the membranes by formation of a cross-linked structure. However, excess immersion in solution containing cross-linker led to an increase in the hydrophobicity of cross-linked membrane. Therefore, the water/ethanol selectivity of Alg-DNA/Mg(2+) cross-linked membranes with an excess immersion in cross-linking solution was lowered. The relationship between the structure of Alg-DNA/Ca(2+) and Alg-DNA/Mg(2+) cross-linked membranes and their permeation and separation characteristics during pervaporation of an ethanol/water azeotropic mixture is discussed in detail. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Legionnaires' Disease acquired within the homes of two patients: link to the home water supply

    International Nuclear Information System (INIS)

    Stout, J.E.; Yu, V.L.; Muraca, P.

    1987-01-01

    Two patients with sporadic community-acquired legionnaires' disease are described. Legionella pneumophila was isolated from sputum specimens, and seroconversion of antibody titers was demonstrated for both patients. Legionella pneumophila was also recovered from the residential water supply of both patients. In each case, the serogroup of the environmental organism matched that of the infecting organism. In one patient, serogroup 3 was isolated - a rare cause of legionnaires' disease, and in the second case, monoclonal antibody testing confirmed that the serogroup 1 organisms isolated from sputum and residential water supply samples were identical. The incubation period of legionnaires' disease is presumed to be up to two weeks. Because of medical problems, both patients had been confined to their homes for the entire two weeks before the onset of symptoms. This is the first report that links acquisition of community-acquired legionnaires' disease to contaminated water supplies within the homes of susceptible patients

  2. Enzyme-linked immunosorbent assay (ELISA) for the anthropogenic marker isolithocholic acid in water.

    Science.gov (United States)

    Baldofski, Stefanie; Hoffmann, Holger; Lehmann, Andreas; Breitfeld, Stefan; Garbe, Leif-Alexander; Schneider, Rudolf J

    2016-11-01

    Bile acids are promising chemical markers to assess the pollution of water samples with fecal material. This study describes the optimization and validation of a direct competitive enzyme-linked immunosorbent assay for the bile acid isolithocholic acid (ILA). The quantification range of the optimized assay was between 0.09 and 15 μg/L. The assay was applied to environmental water samples. Most studies until now were focused on bile acid fractions in the particulate phase of water samples. In order to avoid tedious sample preparation, we undertook to evaluate the dynamics and significance of ILA levels in the aqueous phase. Very low concentrations in tap and surface water samples made a pre-concentration step necessary for this matrix as well as for wastewater treatment plant (WWTP) effluent. Mean recoveries for spiked water samples were between 97% and 109% for tap water and WWTP influent samples and between 102% and 136% for WWTP effluent samples. 90th percentiles of intra-plate and inter-plate coefficients of variation were below 10% for influents and below 20% for effluents and surface water. ILA concentrations were quantified in the range of 33-72 μg/L in influent, 21-49 ng/L in effluent and 18-48 ng/L in surface water samples. During wastewater treatment the ILA levels were reduced by more than 99%. ILA concentrations of influents determined by ELISA and LC-MS/MS were in good agreement. However, findings in LC-ELISA experiments suggest that the true ILA levels in concentrated samples are lower due to interfering effects of matrix compounds and/or cross-reactants. Yet, the ELISA will be a valuable tool for the performance check and comparison of WWTPs and the localization of fecal matter input into surface waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Bridging the Gap: The 'Soft Path' for Improving Resilience and Adaptability of Water Systems (Invited)

    Science.gov (United States)

    Gleick, P. H.

    2010-12-01

    The failure of traditional water management systems in the 20th century -- what I call the "hard path for water" -- is evident in several ways, including the persistent inability to meet basic human needs for safe water and adequate sanitation for vast populations, ongoing and accelerating aquatic ecosystem collapses , and growing political disputes over water allocation, management, and use, even in regions where substantial investment in water has been made. Progress in resolving these problems, especially in the face of unavoidable climate changes, growing populations, and constrained financial systems, will require bridging hydrologic and social sciences in new ways. Integrating social and cultural knowledge with new economic and technological tools and classical hydrologic and climatological sciences can produce a new “soft path for water” that offers the opportunity to move toward sustainable water systems. This talk will define the soft path for water and offer examples of innovative steps already being taken along that path in the western United States, South Africa, India, and elsewhere.

  4. The use of artificial impoundments by two amphibian species in the Delaware Water Gap National Recreation Area

    Science.gov (United States)

    Julian, J.T.; Snyder, C.D.; Young, J.A.

    2006-01-01

    We compared breeding activity of Ambystoma maculatum (Spotted Salamander) and Rana sylvatica (Wood Frog) in artificial impoundments to patterns in natural wetlands over a three-year period in the Delaware Water Gap National Recreation Area. Rana sylvatica were 5.6 times more likely to use natural bodies of water for breeding than artificial impoundments, while A. maculatum were 2.7 times more likely to use natural bodies of water. Both species were approximately 9 times more likely to breed in fishless bodies of water than in waters with predatory fish. Ambystoma maculatum were 6 times more likely to breed in wetlands with more stable seasonal hydroperiods, while R. sylvatica were only 2 times more likely to do so. We conclude that the high likelihood of fish presence in impoundments was the primary explanation for why both species were less likely to use impoundments than natural wetlands, while the tendency of A. maculatum to avoid natural wetlands with shorter hydroperiods explained why differences in use between pond types was more pronounced for R. sylvatica.

  5. Gastrointestinal illness linked to incidents in drinking water distribution networks in Sweden.

    Science.gov (United States)

    Säve-Söderbergh, Melle; Bylund, John; Malm, Annika; Simonsson, Magnus; Toljander, Jonas

    2017-10-01

    During recent years, knowledge gaps on drinking water-related gastrointestinal illness have been identified, especially for non-epidemic cases. Pathogen contamination of drinking water during distribution has been suggested to contribute to these cases, but the risk factors are not yet fully understood. During 2014-2015, we conducted an epidemiological study in five municipalities in Sweden, to assess whether incidents in the drinking water distribution system influence the risk of gastrointestinal illness. Telephone interviews were conducted in the affected areas and in reference areas 7-14 days after a reported incident. Symptoms of gastrointestinal illness occurring during the period were documented for each household member. The results showed a significantly elevated risk of vomiting and acute gastrointestinal illness (AGI) in the affected areas, compared to the reference areas (OR vom.  = 2.0, 95% CI: 1.2-3.3; OR AGI  = 1.9, 95% CI: 1.2-3.0). Certain conditions, or risk factors, during the incidents, such as sewage and drinking water pipelines at the same level in the trench, were associated with an elevated risk of AGI and vomiting. Safety measures taken during repair work, like flushing, were also associated with an elevated risk of AGI and vomiting. These results show that incidents in the drinking water distribution network contribute to endemic gastrointestinal illness, especially AGI and vomiting, and that external pathogen contamination of the drinking water is a likely cause of these cases of gastrointestinal illness. The results also indicate that safety measures used today may not be sufficient for eliminating the risk of gastrointestinal illness. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Water and sanitation hygiene in South Sudan: What needs to be done to bridge the gap?

    Directory of Open Access Journals (Sweden)

    Victor Vuni Joseph

    2014-05-01

    Full Text Available Water, and sanitation hygiene (WASH is a major public health challenge, not only globally, but also in the Republic of South Sudan. It is estimated that 1 in 10 (768 million of the world’s population do not have access to safe drinking water, most of whom are in developing countries, while a third of the world’s population (2.5 billion people do not have access to adequate sanitation

  7. Meeting report: knowledge and gaps in developing microbial criteria for inland recreational waters

    Science.gov (United States)

    Dorevitch, Samuel; Ashbolt, Nicholas J.; Ferguson, Christobel M.; Fujioka, Roger; McGee, Charles D.; Soller, Jeffrey A.; Whitman, Richard L.

    2010-01-01

    The U.S. Environmental Protection Agency (EPA) has committed to issuing in 2012 new or revised criteria designed to protect the health of those who use surface waters for recreation. For this purpose, the U.S. EPA has been conducting epidemiologic studies to establish relationships between microbial measures of water quality and adverse health outcomes among swimmers. New methods for testing water quality that would provide same-day results will likely be elements of the new criteria. Although the epidemiologic studies upon which the criteria will be based were conducted at Great Lakes and marine beaches, the new water quality criteria may be extended to inland waters (IWs). Similarities and important differences between coastal waters (CWs) and IWs that should be considered when developing criteria for IWs were the focus of an expert workshop. Here, we summarize the state of knowledge and research needed to base IWs microbial criteria on sound science. Two key differences between CWs and IWs are the sources of indicator bacteria, which may modify the relationship between indicator microbes and health risk, and the relationship between indicators and pathogens, which also may vary within IWs. Monitoring using rapid molecular methods will require the standardization and simplification of analytical methods, as well as greater clarity about their interpretation. Research needs for the short term and longer term are described.

  8. Linking carbon and water limitations to drought-induced mortality of Pinus flexilis seedlings

    Science.gov (United States)

    Reinhardt, Keith; Germino, Matthew J.; Kueppers, Lara M.; Domec, Jean-Christophe; Mitton, Jeffry

    2015-01-01

    Survival of tree seedlings at high elevations has been shown to be limited by thermal constraints on carbon balance, but it is unknown if carbon relations also limit seedling survival at lower elevations, where water relations may be more important. We measured and modeled carbon fluxes and water relations in first-year Pinus flexilis seedlings in garden plots just beyond the warm edge of their natural range, and compared these with dry-mass gain and survival across two summers. We hypothesized that mortality in these seedlings would be associated with declines in water relations, more so than with carbon-balance limitations. Rather than gradual declines in survivorship across growing seasons, we observed sharp, large-scale mortality episodes that occurred once volumetric soil-moisture content dropped below 10%. By this point, seedling water potentials had decreased below −5 MPa, seedling hydraulic conductivity had decreased by 90% and seedling hydraulic resistance had increased by >900%. Additionally, non-structural carbohydrates accumulated in aboveground tissues at the end of both summers, suggesting impairments in phloem-transport from needles to roots. This resulted in low carbohydrate concentrations in roots, which likely impaired root growth and water uptake at the time of critically low soil moisture. While photosynthesis and respiration on a leaf area basis remained high until critical hydraulic thresholds were exceeded, modeled seedling gross primary productivity declined steadily throughout the summers. At the time of mortality, modeled productivity was insufficient to support seedling biomass-gain rates, metabolism and secondary costs. Thus the large-scale mortality events that we observed near the end of each summer were most directly linked with acute, episodic declines in plant hydraulic function that were linked with important changes in whole-seedling carbon relations.

  9. Linking carbon and water relations to drought-induced mortality in Pinus flexilis seedlings.

    Science.gov (United States)

    Reinhardt, Keith; Germino, Matthew J; Kueppers, Lara M; Domec, Jean-Christophe; Mitton, Jeffry

    2015-07-01

    Survival of tree seedlings at high elevations has been shown to be limited by thermal constraints on carbon balance, but it is unknown if carbon relations also limit seedling survival at lower elevations, where water relations may be more important. We measured and modeled carbon fluxes and water relations in first-year Pinus flexilis seedlings in garden plots just beyond the warm edge of their natural range, and compared these with dry-mass gain and survival across two summers. We hypothesized that mortality in these seedlings would be associated with declines in water relations, more so than with carbon-balance limitations. Rather than gradual declines in survivorship across growing seasons, we observed sharp, large-scale mortality episodes that occurred once volumetric soil-moisture content dropped below 10%. By this point, seedling water potentials had decreased below -5 MPa, seedling hydraulic conductivity had decreased by 90% and seedling hydraulic resistance had increased by >900%. Additionally, non-structural carbohydrates accumulated in aboveground tissues at the end of both summers, suggesting impairments in phloem-transport from needles to roots. This resulted in low carbohydrate concentrations in roots, which likely impaired root growth and water uptake at the time of critically low soil moisture. While photosynthesis and respiration on a leaf area basis remained high until critical hydraulic thresholds were exceeded, modeled seedling gross primary productivity declined steadily throughout the summers. At the time of mortality, modeled productivity was insufficient to support seedling biomass-gain rates, metabolism and secondary costs. Thus the large-scale mortality events that we observed near the end of each summer were most directly linked with acute, episodic declines in plant hydraulic function that were linked with important changes in whole-seedling carbon relations. © The Author 2015. Published by Oxford University Press. All rights reserved

  10. GAP Analysis Program (GAP)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas GAP Analysis Land Cover database depicts 43 land cover classes for the state of Kansas. The database was generated using a two-stage hybrid classification...

  11. The biophysical link between climate, water, and vegetation in bioenergy agro-ecosystems

    International Nuclear Information System (INIS)

    Bagley, Justin E.; Davis, Sarah C.; Georgescu, Matei; Hussain, Mir Zaman; Miller, Jesse; Nesbitt, Stephen W.; VanLoocke, Andy; Bernacchi, Carl J.

    2014-01-01

    Land use change for bioenergy feedstocks is likely to intensify as energy demand rises simultaneously with increased pressure to minimize greenhouse gas emissions. Initial assessments of the impact of adopting bioenergy crops as a significant energy source have largely focused on the potential for bioenergy agroecosystems to provide global-scale climate regulating ecosystem services via biogeochemical processes. Such as those processes associated with carbon uptake, conversion, and storage that have the potential to reduce global greenhouse gas emissions (GHG). However, the expansion of bioenergy crops can also lead to direct biophysical impacts on climate through water regulating services. Perturbations of processes influencing terrestrial energy fluxes can result in impacts on climate and water across a spectrum of spatial and temporal scales. Here, we review the current state of knowledge about biophysical feedbacks between vegetation, water, and climate that would be affected by bioenergy-related land use change. The physical mechanisms involved in biophysical feedbacks are detailed, and interactions at leaf, field, regional, and global spatial scales are described. Locally, impacts on climate of biophysical changes associated with land use change for bioenergy crops can meet or exceed the biogeochemical changes in climate associated with rising GHG's, but these impacts have received far less attention. Realization of the importance of ecosystems in providing services that extend beyond biogeochemical GHG regulation and harvestable yields has led to significant debate regarding the viability of various feedstocks in many locations. The lack of data, and in some cases gaps in knowledge associated with biophysical and biochemical influences on land–atmosphere interactions, can lead to premature policy decisions. - Highlights: • The physical basis for biophysical impacts of expanding bioenergy agroecosystems on climate and water is described. • We

  12. Sedimentary noise and sea levels linked to land-ocean water exchange and obliquity forcing.

    Science.gov (United States)

    Li, Mingsong; Hinnov, Linda A; Huang, Chunju; Ogg, James G

    2018-03-08

    In ancient hothouses lacking ice sheets, the origins of large, million-year (myr)-scale sea-level oscillations remain a mystery, challenging current models of sea-level change. To address this mystery, we develop a sedimentary noise model for sea-level changes that simultaneously estimates geologic time and sea level from astronomically forced marginal marine stratigraphy. The noise model involves two complementary approaches: dynamic noise after orbital tuning (DYNOT) and lag-1 autocorrelation coefficient (ρ 1 ). Noise modeling of Lower Triassic marine slope stratigraphy in South China reveal evidence for global sea-level variations in the Early Triassic hothouse that are anti-phased with continental water storage variations in the Germanic Basin. This supports the hypothesis that long-period (1-2 myr) astronomically forced water mass exchange between land and ocean reservoirs is a missing link for reconciling geological records and models for sea-level change during non-glacial periods.

  13. Bridging the Gap Between Climate Science and Water-resource Applications

    Science.gov (United States)

    Arnold, J. R.; Clark, M. P.; Wood, A.; Gutmann, E. D.; Nijssen, B.; Brekke, L. D.

    2015-12-01

    Since 2010, the US Army Corps of Engineers (USACE) Climate Preparedness and Resilience Program has supported development of a coordinated system of products and tools to improve use of climate information in water-resource planning and management. The key products include: 1) a new understanding of the limitations of methods used to quantify impacts of climate change on water resources; 2) development and evaluation of national-domain climate downscaling and hydrologic simulation capabilities to provide information from climate model output relevant to the multiple scales of water resources decision-making with a spatially consistent assessment of the impacts of climate change on hydrologic conditions; and 3) development and evaluation of advanced streamflow forecasting methods. This will support USACE Districts and their stakeholders and partners with new data, new and newly evaluated model output, and specific tools in a framework to help with routine applications for managing water resources throughout the U.S., and to enhance considerations of climate preparedness and resilience in that work. This presentation will summarize the collaborative development of some of those products; describe current and planned future USACE capabilities for incorporating advanced climate information at multiple scales of analysis and decision; discuss uses of climate information in water-resources planning and management; and outline key unanswered science questions being addressed to increase utility and use of information in short- and longer-term planning. Specifically, we will describe the current suite and planned trajectory of new products, moving from capability development through to testing in limited pilot domains, on to product applications throughout the U.S., and, ultimately, into actual implementation at the level of USACE Districts to address climate change issues. Two key foci of this talk will be: 1) where climatological and hydrologic science is currently

  14. Ecosystem-groundwater interactions under changing land uses: Linking water, salts, and carbon across central Argentina

    Science.gov (United States)

    Jobbagy, E. G.; Nosetto, M. D.; Santoni, C. S.; Jackson, R. B.

    2007-05-01

    Although most ecosystems display a one-way connection with groundwater based on the regulation of deep water drainage (recharge), this link can become reciprocal when the saturated zone is shallow and plants take up groundwater (discharge). In what context is the reciprocal link most likely? How is it affected by land use changes? Has it consequences on salt and carbon cycling? We examine these questions across a precipitation gradient in the Pampas and Espinal of Argentina focusing on three vegetation change situations (mean annual rainfall): afforestation of humid (900-1300 mm) and subhumid grassland (700-900 mm/yr of rainfall), annual cultivation of subhumid grasslands (700-800 mm/yr), and annual cultivation of semiarid forests (500-700 mm). Humid and subhumid grasslands have shallow (measurements. Groundwater contributions enhance carbon uptake in plantations compared to grasslands as suggested by aboveground biomass measurements and satellite vegetation indexes from sites with and without access to groundwater. Where rainfall is 15 m deep) and recharge under natural conditions is null. The establishment of crops, however, triggers the onset of recharge, as evidenced by vadose zones getting wetter and leached of atmospheric chloride. Cropping may cause water table raises leading to a two-way coupling of ecosystems and groundwater in the future, as it has been documented for similar settings in Australia and the Sahel. In the Pampas land use change interacts with groundwater consumption leading to higher carbon uptake (humid and subhumid grasslands) and salt accumulation (subhumid grasslands). In the Espinal (semiarid forest) land use change currently involves a one-way effect on groundwater recharge that may switch to a reciprocal connection if regional water table raises occur. Neglecting the role of groundwater in flat sedimentary plains can obscure our understanding of carbon and salt cycling and curtail our attempts to sustain soil and water resources under

  15. Multifunctional Binary Monolayers Ge xP y: Tunable Band Gap, Ferromagnetism, and Photocatalyst for Water Splitting.

    Science.gov (United States)

    Li, Pengfei; Zhang, Wei; Li, Dongdong; Liang, Changhao; Zeng, Xiao Cheng

    2018-06-04

    The most stable structures of two-dimensional Ge x P y and Ge x As y monolayers with different stoichiometries (e.g., GeP, GeP 2 , and GeP 3 ) are explored systematically through the combination of the particle-swarm optimization technique and density functional theory optimization. For GeP 3 , we show that the newly predicted most stable C2/ m structure is 0.16 eV/atom lower in energy than the state-of-the-art P3̅m1 structure reported previously ( Nano Lett. 2017, 17, 1833). The computed electronic band structures suggest that all the stable and metastable monolayers of Ge x P y are semiconductors with highly tunable band gaps under the biaxial strain, allowing strain engineering of their band gaps within nearly the whole visible-light range. More interestingly, the hole doping can convert the C2/ m GeP 3 monolayer from nonmagnetic to ferromagnetic because of its unique valence band structure. For the GeP 2 monolayer, the predicted most stable Pmc2 1 structure is a (quasi) direct-gap semiconductor that possesses a high electron mobility of ∼800 cm 2 V -1 s -1 along the k a direction, which is much higher than that of MoS 2 (∼200 cm 2 V -1 s -1 ). More importantly, the Pmc2 1 GeP 2 monolayer not only can serve as an n-type channel material in field-effect transistors but also can be an effective catalyst for splitting water.

  16. Water relations link carbon and oxygen isotope discrimination to phloem sap sugar concentration in eucalyptus globulus

    International Nuclear Information System (INIS)

    Cernusak, L.A.; Farquhar, G.D.; Arthur, D.J; Pate, J.S.

    2002-01-01

    Full text: The carbon isotope ratio of phloem sap sugars has been previously observed to correlate strongly with the phloem sap sugar concentration in Eucalyptus globulus. We hypothesized that the correspondence between these two parameters results from co-linearity in their responses to variation in plant water potential. Carbon isotope discrimination is expected to decrease with decreasing plant water potential due to the influence of stomatal conductance on the ratio of intercellular to ambient CO 2 , concentrations (c 1 /c a ). Conversely, we expected the phloem sap sugar concentration to increase with decreasing plant water potential, thereby maintaining positive turgor pressure within the sieve tubes. The study comprised 40 individual Eucalyptus globulus trees growing in three plantations situated on opposing ends of a rainfall gradient in southwestern Australia. A strong correlation was observed between the carbon isotope ratio in phloem sap sugars and phloem sap sugar concentration. Carbon isotope discrimination correlated positively with shoot water potential, whereas phloem sap sugar concentration correlated negatively with shoot water potential. The relationship between carbon isotope discrimination measured in phloem sap sugars collected from the stem and c 1 /c a measured instantaneously on subtending leaves was close to that theoretically predicted. Accordingly, a strong, negative relationship was observed between instantaneous c 1 /c a and the phloem sap sugar concentration. Oxygen isotope discrimination in phloem sap sugars also correlated strongly with phloem sap sugar concentration. A theoretical model suggested that the observed variation in stomatal conductance was sufficient to account for the variation observed in oxygen isotope discrimination across the study. Results strongly support the contention that water relations form a mechanistic link between phloem sap sugar concentration and both instantaneous and integrated measures of the

  17. Inter-Basin Water Transfer Impact Assessment on Environment of Pennar to Cauvery Link Canal

    Science.gov (United States)

    Rajesh, S. V. J. S. S.; Prakasa Rao, B. S.; Niranjan, K.

    2016-07-01

    Owing to its striking differences in its climatic conditions, India is frequently facing with extremities such as heavy rain fall in some regions where as some other regions endure little rainfall. The regions receiving heavy precipitation are facing floods resulting in huge amount of water runs into the sea. Contrarily, the regions, without adequate rainfall are suffering from persistent droughts. To overcome such disparities in the distribution of water, National Water Development Agency (NWDA) put a proposal to transfer water through link canals between rivers. The current study is limited to two river basins, Pennar and Cauvery. The present study is confined to Pennar (somasila) to Cauvery (Grand Anicut) whose length is 483 km. The study consist of10 km. buffer on either side of the canal and it occupies 17,215.68 sq. km. out of these 10,105.96 sq.km.is proposed command area which falls in Chittoor, Chengalpattu, North Arcott and South Arcott districts. Using IRS-P6, LISS-III data the characteristics of the rocks, lineaments, drainage, settlements and land use/land cover are mapped for better analysis and the environmental impact. The study indicated that Current fallow land of 5340.14 km2 and 6307.98 km2 of cropland will be brought under cultivation which is more than what is NWDA estimated land that will be benefited. The canal will provide water for irrigation and drinking to 4597 villages and 244 villages to be rehabilitated. 119 culverts/canal bridges and 24 aqueducts have to be constructed across the canal.

  18. A cluster of cases of nosocomial legionnaires disease linked to a contaminated hospital decorative water fountain.

    Science.gov (United States)

    Palmore, Tara N; Stock, Frida; White, Margaret; Bordner, MaryAnn; Michelin, Angela; Bennett, John E; Murray, Patrick R; Henderson, David K

    2009-08-01

    Nosocomial outbreaks of Legionnaires disease have been linked to contaminated water in hospitals. Immunocompromised patients are particularly vulnerable and, when infected, have a high mortality rate. We report the investigation of a cluster of cases of nosocomial pneumonia attributable to Legionella pneumophila serogroup 1 that occurred among patients on our stem cell transplantation unit. We conducted a record review to identify common points of potential exposure, followed by environmental and water sampling for Legionella species from those sources. We used an air sampler to in an attempt to detect aerosolized Legionella and pulsed-field gel electrophoresis to compare clinical and environmental isolates. The most likely sources identified were the water supply in the patients' rooms and a decorative fountain in the radiation oncology suite. Samples from the patients' rooms did not grow Legionella species. Cultures of the fountain, which had been restarted 4 months earlier after being shut off for 5 months, yielded L. pneumophila serogroup 1. The isolates from both patients and the fountain were identical by pulsed-field gel electrophoresis. Both patients developed pneumonia within 10 days of completing radiation therapy, and each reported having observed the fountain at close range. Both patients' infections were identified early and treated promptly, and both recovered. This cluster was caused by contamination of a decorative fountain despite its being equipped with a filter and ozone generator. Fountains are a potential source of nosocomial Legionnaires disease despite standard maintenance and sanitizing measures. In our opinion, fountains present unacceptable risk in hospitals serving immunocompromised patients.

  19. Water and energy link in the cities of the future - achieving net zero carbon and pollution emissions footprint.

    Science.gov (United States)

    Novotny, V

    2011-01-01

    This article discusses the link between water conservation, reclamation, reuse and energy use as related to the goal of achieving the net zero carbon emission footprint in future sustainable cities. It defines sustainable ecocities and outlines quantitatively steps towards the reduction of energy use due to water and used water flows, management and limits in linear and closed loop water/stormwater/wastewater management systems. The three phase water energy nexus diagram may have a minimum inflection point beyond which reduction of water demand may not result in a reduction of energy and carbon emissions. Hence, water conservation is the best alternative solution to water shortages and minimizing the carbon footprint. A marginal water/energy chart is developed and proposed to assist planners in developing future ecocities and retrofitting older communities to achieve sustainability.

  20. Water Resource Assessment, Gaps, and Constraints of Vegetable Production in Robit and Dangishta Watersheds, Upper Blue Nile Basin, Ethiopia

    Science.gov (United States)

    Worqlul, A. W.; Dile, Y.; Jeong, J.; Schmitter, P.; Bizimana, J. C.; Gerik, T.; Srinivasan, R.; Richardson, J. W.; Clarke, N.

    2017-12-01

    Rainfed agriculture supports the majority of the poor in sub-Saharan Africa. However, rainfall variability, land degradation and low soil fertility lessen their effectiveness for feeding the growing population. This study aims to estimate the water resources potential to sustain small-scale irrigation (SSI) in Ethiopia into the dry season to expand the food supply by growing vegetable and to understand the gaps and constraints of irrigated vegetable production. The case studies were located in Robit and Dangishta watersheds of the Ethiopian highlands near Lake Tana, where detailed field-level data were collected. The study focused on data from 18 households who have been cultivating tomato and onion during the dry season using irrigation in each watershed. The two components of the Integrated Decision Support System (IDSS) - the Soil and Water Assessment Tool (SWAT) and Agricultural Policy Environmental eXtender (APEX) - were used to assess impacts of SSI at multiple scales. Results suggest that there is a substantial amount of surface runoff and shallow groundwater recharge at watershed scale. The field-scale analysis within the Robit watershed indicated that optimal tomato yield could be obtained with 450 mm of irrigation and 200 to 250 kg/ha of urea with 50 kg/ha of diammonium phosphate (DAP). In Dangishta, optimum onion yield can be obtained by applying 550 mm irrigation and 120 to 180 kg/ha of urea with 50 kg/ha of DAP. Studying field scale water balance, the average shallow groundwater recharge (after accounting other groundwater users such as household and livestock uses) was not sufficient to meet tomato and onion water demand. The field-scale analysis also indicated that soil evaporation attributed a significant proportion of evapotranspiration (i.e. 60% of the evapotranspiration for onion and 40% for tomato). Use of mulching or other soil and water conservation interventions could increase water for cropping by reducing soil evaporation thereby enhancing

  1. Dually cross-linked single network poly(acrylic acid) hydrogels with superior mechanical properties and water absorbency.

    Science.gov (United States)

    Zhong, Ming; Liu, Yi-Tao; Liu, Xiao-Ying; Shi, Fu-Kuan; Zhang, Li-Qin; Zhu, Mei-Fang; Xie, Xu-Ming

    2016-06-28

    Poly(acrylic acid) (PAA) hydrogels with superior mechanical properties, based on a single network structure with dual cross-linking, are prepared by one-pot free radical polymerization. The network structure of the PAA hydrogels is composed of dual cross-linking: a dynamic and reversible ionic cross-linking among the PAA chains enabled by Fe(3+) ions, and a sparse covalent cross-linking enabled by a covalent cross-linker (Bis). Under deformation, the covalently cross-linked PAA chains remain intact to maintain their original configuration, while the Fe(3+)-enabled ionic cross-linking among the PAA chains is broken to dissipate energy and then recombined. It is found that the mechanical properties of the PAA hydrogels are significantly influenced by the contents of covalent cross-linkers, Fe(3+) ions and water, which can be adjusted within a substantial range and thus broaden the applications of the hydrogels. Meanwhile, the PAA hydrogels have excellent recoverability based on the dynamic and reversible ionic cross-linking enabled by Fe(3+) ions. Moreover, the swelling capacity of the PAA hydrogels is as high as 1800 times in deionized water due to the synergistic effects of ionic and covalent cross-linkings. The combination of balanced mechanical properties, efficient recoverability, high swelling capacity and facile preparation provides a new method to obtain high-performance hydrogels.

  2. Extreme diving behaviour in devil rays links surface waters and the deep ocean

    KAUST Repository

    Thorrold, Simon R.

    2014-07-01

    Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food webs containing a suite of predators that include commercially important fishes and marine mammals. Here we deploy pop-up satellite archival transmitting tags on 15 Chilean devil rays (Mobula tarapacana) in the central North Atlantic Ocean, which provide movement patterns of individuals for up to 9 months. Devil rays were considered surface dwellers but our data reveal individuals descending at speeds up to 6.0 ms-1 to depths of almost 2,000 m and water temperatures <4 C. The shape of the dive profiles suggests that the rays are foraging at these depths in deep scattering layers. Our results provide evidence of an important link between predators in the surface ocean and forage species occupying pelagic habitats below the euphotic zone in ocean ecosystems. 2014 Macmillan Publishers Limited. All rights reserved.

  3. Hydraulically Induced Seismicity in South-Eastern Brazil Linked to Water Wells

    Science.gov (United States)

    Convers, J.; Assumpcao, M.; Barbosa, J. R.

    2017-12-01

    While hydraulic stimulus on seismic activity is most commonly associated with hydraulic fracturing processes, we find in SE Brazil a rare case of seismicity influenced by hydraulic stimulation linked to seasonal rain and water wells in a farming area. These are thought to be the main factors influencing the seasonal seismicity activity in Jurupema, a farming town located in the interior of the state of Sao Paulo, southern Brazil. With temporary seismic station deployments during 2016 and 2017, we analyze the seismicity in this area, its temporal and spatial distribution, and its association with the drilling of ground water wells in this particular area. In a region where water wells are often drilled to provide irrigation for farming, these are often perforated down to about 100 m depth, penetrating below the uppermost sandstone rock layer ( 50 m) into a fractured basaltic rock layer, reaching the confined aquifer within it. While the wells are constantly pumped during the dry season, during the course of the rainy season (when these are not being used), a possible infiltration into the confined basaltic aquifer, from both the rainwater and the upper sandstone aquifer, adds changes to the pore pressure of the fractured rock, and modifies the tectonic pre-stress conditions, to facilitate stress release mechanisms in pre-existing faults and cracks. With our temporary seismic station deployments, we not only examine the seismicity in this region during both 2016 and 2017, but we additionally compare its characteristics to the nearby Bebedouro case in an apparent induced seismic case of analogous source, and seismic activity with magnitudes up to 2.9 occurring between 2005 and 2010.

  4. Effect of operating parameters and membrane characteristics on air gap membrane distillation performance for the treatment of highly saline water

    KAUST Repository

    Xu, Jingli

    2016-04-07

    In this study, ten different commercially available PTFE, PP and PVDF membranes were tested in desalination of highly saline water by air gap membrane distillation (AGMD). Process performance was investigated under different operating parameters, such as feed temperatures, feed flow velocities and salt concentrations reaching 120 g/L, and different membrane characteristics, such as membrane material, thickness, pore size and support layer, using a locally designed and fabricatd AGMD module and spacer. Results showed that increasing feed temperature increases permeate flux regardless of the feed concentration. However, feed flow velocity does not significantly affect the flux, especially at low feed temperatures. The PP membrane showed a better performance than the PVDF and PTFE membranes. Permeate flux decreases with the increase of salt concentration of feed solution, especially at higher concentrations above 90 g/L. The existence of membrane support layer led to a slight decrease of permeate flux. Membranes with pore sizes of 0.2 and 0.45 μm gave the best performance. Smaller pore size led to lower flux and larger pore size led to pore wetting due to lower LEP values. The effect of concentration polarization and temperature polarization has also been studied and compared.

  5. Zero-Gap Alkaline Water Electrolysis Using Ion-Solvating Polymer Electrolyte Membranes at Reduced KOH Concentrations

    DEFF Research Database (Denmark)

    Kraglund, Mikkel Rykær; Aili, David; Jankova Atanasova, Katja

    2016-01-01

    Membranes based on poly(2,2'-(m-phenylene)-5,5-bibenzimidazole) (m-PBI) can dissolve large amounts of aqueous KOH to give electrolyte systems with ion conductivity in a practically useful range. The conductivity of the membrane strongly depends on the concentration of the aqueous KOH phase......, reaching about 10-1 S cm-1 or higher in 15-25 wt% KOH. Herein, m-PBI membranes are systematically characterized with respect to performance and short-term stability as electrolyte in a zero-gap alkaline water electrolyzer at different KOH concentrations. Using plain uncatalyzed nickel foam electrodes......, the cell based on m-PBI outperforms the cell based on the commercially available state-of-the-art diaphragm and reaches a current density of 1500 mA cm-2 at 2.4 V in 20 wt% KOH at 80°C. The cell performance remained stable during two days of operation, though post analysis of the membrane using size...

  6. The effects of gaseous bubble composition and gap distance on the characteristics of nanosecond discharges in distilled water

    KAUST Repository

    Hamdan, Ahmad

    2016-05-17

    Electric discharge in liquids with bubbles can reduce the energy consumption, which increases treatment efficiency. We present an experimental study of nanosecond discharges in distilled water bubbled with the monoatomic gas argon and with the polyatomic gases methane, carbon dioxide, and propane. We monitor the time evolution of the voltage and current waveforms, and calculate the injected charges to characterize the discharge. We establish a relationship between the injected charges and the shape of the plasma by time-resolved imaging to find that increasing the size of the gap reduces the injected charges. Moreover, we determine the plasma characteristics, including electron density, excitation temperatures (for atoms and ions), and rotational temperature of the OH and C2 radicals found in the plasma. Our space- and time-averaged measurements allow us to propose a spatial distribution of the plasma that is helpful for understanding the plasma dynamics necessary to develop and optimize applications based on nanosecond discharges in bubbled liquids. © 2016 IOP Publishing Ltd.

  7. Public-Elite Gap on European Integration : The Missing Link between Discourses about EU Enlargement among Citizens and Elites in Serbia

    NARCIS (Netherlands)

    Kortenska, E.G.; Sircar, I.; Steunenberg, B.

    2016-01-01

    Enlargement is often regarded as an elite-driven process, which does not or not sufficiently include the views of ordinary citizens. At the same time, support for integration has been eroding over the last decade, contributing to a public-elite gap in preferences towards the process. This paper

  8. Filling the gap: using non-invasive geophysical methods to monitor the processes leading to enhanced carbon turnover induced by periodic water table fluctuations

    Science.gov (United States)

    Mellage, A.; Pronk, G.; Atekwana, E. A.; Furman, A.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Subsurface transition environments such as the capillary fringe are characterized by steep gradients in redox conditions. Spatial and temporal variations in electron acceptor and donor availability - driven by hydrological changes - may enhance carbon turnover, in some cases resulting in pulses of CO2-respiration. Filling the mechanistic knowledge gap between the hydrological driver and its biogeochemical effects hinges on our ability to monitor microbial activity and key geochemical markers at a high spatial and temporal resolution. However, direct access to subsurface biogeochemical processes is logistically difficult, invasive and usually expensive. In-line, non-invasive geophysical techniques - Spectral Induced Polarization (SIP) and Electrodic Potential (EP), specifically - offer a comparatively inexpensive alternative and can provide data with high spatial and temporal resolution. The challenge lies in linking electrical responses to specific changes in biogeochemical processes. We conducted SIP and EP measurements on a soil column experiment where an artificial soil mixture was subjected to monthly drainage and imbibition cycles. SIP responses showed a clear dependence on redox zonation and microbial abundance. Temporally variable responses exhibited no direct moisture dependence suggesting that the measured responses recorded changes in microbial activity and coincided with the depth interval over which enhanced carbon turnover was observed. EP measurements detected the onset of sulfate mineralization and mapped its depth zonation. SIP and EP signals thus detected enhanced microbial activity within the water table fluctuation zone as well as the timing of the development of specific reactive processes. These findings can be used to relate measured electrical signals to specific reaction pathways and help inform reactive transport models, increasing their predictive capabilities.

  9. Critical heat flux analysis on change of plate temperature and cooling water flow rate for rectangular narrow gap with bilateral-heated cases

    International Nuclear Information System (INIS)

    M Hadi Kusuma; Mulya Juarsa; Anhar Riza Antariksawan

    2013-01-01

    Boiling heat transfer phenomena on rectangular narrow gap was related to the safety of nuclear reactors. Research done in order to study the safety of nuclear reactors in particular relating to boiling heat transfer and useful on the improvement of next-generation reactor designs. The research focused on calculation of the heat flux during the cooling process in rectangular narrow gap size 1.0 mm. with initial temperatures 200°C. 400°C, and 600°C, also the flow rates of cooling water 0,1 liters/second. 0,2 liters/second. and 0,3 liters/second. Experiments carried out by injecting water at a certain flow rate with the water temperature 85°C. Transient temperature measurement data recorded by the data acquisition system. Transient temperature measurement data is used to calculate the flux of heat gain is then used to obtain the heat transfer coefficient. This research aimed to obtain the correlation between critical heat flux and heat transfer coefficient to changes in temperatures and water flow rates for bilaterally-heated cases on rectangular narrow gap. The results obtained for a constant cooling water flow rate, critical heat flux will increase when hot plate temperature also increased. While on a constant hot plate temperature, coefficient heat transfer will increase when cooling water flow rate also increased. Thus it can be said that the cooling water flow rate and temperature of the hot plate has a significant effect on the critical heat flux and heat transfer coefficient resulted in quenching process of vertical rectangular narrow gap with double-heated cases. (author)

  10. Dynamical electron-phonon coupling, G W self-consistency, and vertex effect on the electronic band gap of ice and liquid water

    Science.gov (United States)

    Ziaei, Vafa; Bredow, Thomas

    2017-06-01

    We study the impact of dynamical electron-phonon (el-ph) effects on the electronic band gap of ice and liquid water by accounting for frequency-dependent Fan contributions in the el-ph mediated self-energy within the many-body perturbation theory (MBPT). We find that the dynamical el-ph coupling effects greatly reduce the static el-ph band-gap correction of the hydrogen-rich molecular ice crystal from-2.46 to -0.23 eV in great contrast to the result of Monserrat et al. [Phys. Rev. B 92, 140302 (2015), 10.1103/PhysRevB.92.140302]. This is of particular importance as otherwise the static el-ph gap correction would considerably reduce the electronic band gap, leading to considerable underestimation of the intense peaks of optical absorption spectra of ice which would be in great disagreement to experimental references. By contrast, the static el-ph gap correction of liquid water is very moderate (-0.32 eV), and inclusion of dynamical effects slightly reduces the gap correction to -0.19 eV. Further, we determine the diverse sensitivity of ice and liquid water to the G W self-consistency and show that the energy-only self-consistent approach (GnWn ) exhibits large implicit vertex character in comparison to the quasiparticle self-consistent approach, for which an explicit calculation of vertex corrections is necessary for good agreement with experiment.

  11. Predicting future US water yield and ecosystem productivity by linking an ecohydrological model to WRF dynamically downscaled climate projections

    Science.gov (United States)

    S. Sun; Ge Sun; Erika Cohen Mack; Steve McNulty; Peter Caldwell; K. Duan; Y. Zhang

    2015-01-01

    Quantifying the potential impacts of climate change on water yield and ecosystem productivity (i.e., carbon balances) is essential to developing sound watershed restoration plans, and climate change adaptation and mitigation strategies. This study links an ecohydrological model (Water Supply and Stress Index, WaSSI) with WRF (Weather Research and Forecasting Model)...

  12. Scandinavian links

    DEFF Research Database (Denmark)

    Matthiessen, Christian Wichmann; Knowles, Richard D.

    2014-01-01

    are impressive mega structures spanning international waterways. These waterways between the Baltic Sea and the North Sea have played major roles in history. The length of each of the crossings are around 20 km. The fixed links closes gaps between the Scandinavian and European motorway and rail networks...

  13. Recreation Value of Water to Wetlands in the San Joaquin Valley: Linked Multinomial Logit and Count Data Trip Frequency Models

    Science.gov (United States)

    Creel, Michael; Loomis, John

    1992-10-01

    The recreational benefits from providing increased quantities of water to wildlife and fisheries habitats is estimated using linked multinomial logit site selection models and count data trip frequency models. The study encompasses waterfowl hunting, fishing and wildlife viewing at 14 recreational resources in the San Joaquin Valley, including the National Wildlife Refuges, the State Wildlife Management Areas, and six river destinations. The economic benefits of increasing water supplies to wildlife refuges were also examined by using the estimated models to predict changing patterns of site selection and overall participation due to increases in water allocations. Estimates of the dollar value per acre foot of water are calculated for increases in water to refuges. The resulting model is a flexible and useful tool for estimating the economic benefits of alternative water allocation policies for wildlife habitat and rivers.

  14. The effects of gaseous bubble composition and gap distance on the characteristics of nanosecond discharges in distilled water

    KAUST Repository

    Hamdan, Ahmad; Cha, Min

    2016-01-01

    of the plasma by time-resolved imaging to find that increasing the size of the gap reduces the injected charges. Moreover, we determine the plasma characteristics, including electron density, excitation temperatures (for atoms and ions), and rotational

  15. Ground water security and drought in Africa: linking availability, access, and demand.

    Science.gov (United States)

    Calow, Roger C; Macdonald, Alan M; Nicol, Alan L; Robins, Nick S

    2010-01-01

    Drought in Africa has been extensively researched, particularly from meteorological, agricultural, and food security perspectives. However, the impact of drought on water security, particularly ground water dependent rural water supplies, has received much less attention. Policy responses have concentrated on food needs, and it has often been difficult to mobilize resources for water interventions, despite evidence that access to safe water is a serious and interrelated concern. Studies carried out in Ghana, Malawi, South Africa, and Ethiopia highlight how rural livelihoods are affected by seasonal stress and longer-term drought. Declining access to food and water is a common and interrelated problem. Although ground water plays a vital role in buffering the effects of rainfall variability, water shortages and difficulties in accessing water that is available can affect domestic and productive water uses, with knock-on effects on food consumption and production. Total depletion of available ground water resources is rarely the main concern. A more common scenario is a spiral of water insecurity as shallow water sources fail, additional demands are put on remaining sources, and mechanical failures increase. These problems can be planned for within normal development programs. Water security mapping can help identify vulnerable areas, and changes to monitoring systems can ensure early detection of problems. Above all, increasing the coverage of ground water-based rural water supplies, and ensuring that the design and siting of water points is informed by an understanding of hydrogeological conditions and user demand, can significantly increase the resilience of rural communities to climate variability.

  16. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis.

    Science.gov (United States)

    Trosko, James E

    2016-06-15

    The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules ("quorum sensing"), the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or "connexin" genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC) in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision-making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global "metabolic disease" crisis.

  17. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis

    Directory of Open Access Journals (Sweden)

    James E. Trosko

    2016-06-01

    Full Text Available The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules (“quorum sensing”, the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or “connexin” genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision–making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global “metabolic disease” crisis.

  18. Bridging the gap: linking a legacy hospital information system with a filmless radiology picture archiving and communications system within a nonhomogeneous environment.

    Science.gov (United States)

    Rubin, R K; Henri, C J; Cox, R D

    1999-05-01

    A health level 7 (HL7)-conformant data link to exchange information between the mainframe hospital information system (HIS) of our hospital and our home-grown picture archiving and communications system (PACS) is a result of a collaborative effort between the HIS department and the PACS development team. Based of the ability to link examination requisitions and image studies, applications have been generated to optimise workflow and to improve the reliability and distribution of radiology information. Now, images can be routed to individual radiologists and clinicians; worklists facilitate radiology reporting; applications exist to create, edit, and view reports and images via the internet; and automated quality control now limits the incidence of "lost" cases and errors in image routing. By following the HL7 standard to develop the gateway to the legacy system, the development of a radiology information system for booking, reading, reporting, and billing remains universal and does not preclude the option to integrate off-the-shelf commercial products.

  19. An Assessment of the Water Development Project (GAP) of Turkey: Meeting Its Objectives and EU Criteria for Turkey’s Accession

    Science.gov (United States)

    2010-12-01

    This became the turning point, from the 1980s onwards, in the booming history begun in the 1930s, of large dams and multipurpose projects, where...Experiments with different levels of saline water used in sprinkler irrigation systems have shown that crops such as beans, pepper, lettuce and cotton...developmentalist view on the GAP, characterized by an aggressive support for HEPP constructions, remains constant in modern Turkish history . Suleyman Demiral

  20. Water data to answer urgent water policy questions: Monitoring design, available data, and filling data gaps for determining whether shale gas development activities contaminate surface water or groundwater in the Susquehanna River Basin

    Science.gov (United States)

    Betanzo, Elin A.; Hagen, Erik R.; Wilson, John T.; Reckhow, Kenneth H.; Hayes, Laura; Argue, Denise M.; Cangelosi, Allegra A.

    2016-01-01

    Throughout its history, the United States has made major investments in assessing natural resources, such as soils, timber, oil and gas, and water. These investments allow policy makers, the private sector and the American public to make informed decisions about cultivating, harvesting or conserving these resources to maximize their value for public welfare, environmental conservation and the economy. As policy issues evolve, new priorities and challenges arise for natural resource assessment, and new approaches to monitoring are needed. For example, new technologies for oil and gas development or alternative energy sources may present new risks for water resources both above and below ground. There is a need to evaluate whether today’s water monitoring programs are generating the information needed to answer questions surrounding these new policy priorities. The Northeast-Midwest Institute (NEMWI), in cooperation with the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program, initiated this project to explore the types and amounts of water data needed to address water-quality related policy questions of critical concern to today’s policy makers and whether those data are currently available. The collaborating entities identified two urgent water policy questions and conducted case studies in the Northeast-Midwest region to determine the water data needed, water data available, and the best ways to fill the data gaps relative to those questions. This report details the output from one case study and focuses on the Susquehanna River Basin, a data-rich area expected to be a best-case scenario in terms of water data availability.

  1. Simulating the potential yield and yield gaps of sugar beet due to water and nitrogen limitations in Khorasan province using SUCROS model

    Directory of Open Access Journals (Sweden)

    R Deihimfard

    2015-12-01

    Full Text Available Introduction Crop productivity is highly constrained by water and nitrogen limitations in many areas of the world (Kalra et al., 2007. Therefore, there is a need to investigate more on nitrogen and water management to achieve higher production as well as quality. Irrigated sugar beet in the cropping systems of Khorasan province in northeastern of Iran accounts for about 34% of the land area under sugar beet production (~115,000 ha with an average yield of around 36 t.ha-1 (Anonymous, 2009. However, there is a huge yield gap (the difference between potential and water and nitrogen-limited yield mainly due to biotic and abiotic factors causing major reduction in farmers’ yield. Accordingly, yield gap analysis should be carried out to reduce the yield reduction and reach the farmer’s yield to the potential yield. The current study aimed to simulate potential yield as well as yield gap related to water and nitrogen shortage in the major sugar beet-growing areas of Khorasan province of Iran. Materials and methods This study was carried out in 6 locations across Khorasan province, which is located in the northeast of Iran. Long term weather data for 1986 to 2009 were obtained from Iran Meteorological Organization for 6 selected locations. The weather data included daily sunshine hours (h, daily maximum and minimum temperatures (◦C, and daily rainfall (mm. Daily solar radiation was estimated using the Goudriaan (1993 method. The validated SUCROSBEET model (Deihimfard, 2011; Deihimfard et al., 2011 was then used to estimate potential, water and nitrogen-limited yield and yield gap of sugar beet for 6 selected locations across the Khorasan province in the northeast of Iran. This model simulates the impacts of weather, genotype and management factors on crop growth and development, soil water and nitrogen balance on a daily basis and finally it predicts crop yield. The model requires input data, including local weather and soil conditions, cultivar

  2. Linking levels of societal and ecosystems metabolism of water in a Mediterranean watershed

    Science.gov (United States)

    Cabello, V.

    2014-12-01

    Water resources degradation is a complex environmental problem that involves multiple dimensions and scales of analysis. The Socio-Ecological Systems Water Metabolism has been proposed as a general holistic framework to deal with integrated analysis of water use sustainability (Madrid and Giampietro 2014). The innovation of the approach is that it sets the research focus beyond the classical supply-demand modeling to societal integrity and ecosystems integrity. To do so, it integrates quantitative grammars of water use (relating water exchange to societal and ecosystems organization) and qualitative methods (discourse analysis). This work presents the first case study focused at a river basin extent: the Upper Andarax, in South-East Spain. Water metabolism is indicated at multiple levels for ecosystems and society. To deal with the interfaces among them, relational indicators of water exploitation, water use and impact over ecosystems are used alongside policies and narratives analysis.While being a rather not intensively exploited river basin (year Water Exploitation Index~0.3 blue water,~0.15 green water), impacts over water bodies are yet important (periodic aquifer overdraft, biological degradation of the river) especially during dry season. Perceived mayor problems of water sustainability are generated by the not integration of different policies at European, national and regional scales: while the water authority establishes a compulsory reduction over water withdrawal to attend environmental flows, agricultural markets force to raise productivity increasing water demands. Adaptation strategies are divided among irrigation efficiency improvement and a reorientation of the economy towards touristic activities. Both of them entail specific trade-offs to be deemed. Aquifer-river interactions and climate change impacts are yet mayor research challenges.

  3. Compartmentalization Technologies via Self-Assembly and Cross-Linking of Amphiphilic Random Block Copolymers in Water.

    Science.gov (United States)

    Matsumoto, Mayuko; Terashima, Takaya; Matsumoto, Kazuma; Takenaka, Mikihito; Sawamoto, Mitsuo

    2017-05-31

    Orthogonal self-assembly and intramolecular cross-linking of amphiphilic random block copolymers in water afforded an approach to tailor-make well-defined compartments and domains in single polymer chains and nanoaggregates. For a double compartment single-chain polymer, an amphiphilic random block copolymer bearing hydrophilic poly(ethylene glycol) (PEG) and hydrophobic dodecyl, benzyl, and olefin pendants was synthesized by living radical polymerization (LRP) and postfunctionalization; the dodecyl and benzyl units were incorporated into the different block segments, whereas PEG pendants were statistically attached along a chain. The copolymer self-folded via the orthogonal self-assembly of hydrophobic dodecyl and benzyl pendants in water, followed by intramolecular cross-linking, to form a single-chain polymer carrying double yet distinct hydrophobic nanocompartments. A single-chain cross-linked polymer with a chlorine terminal served as a globular macroinitiator for LRP to provide an amphiphilic tadpole macromolecule comprising a hydrophilic nanoparticle and a hydrophobic polymer tail; the tadpole thus self-assembled into multicompartment aggregates in water.

  4. Coastal upwelling linked to toxic Pseudo-nitzschia australis blooms in Los Angeles coastal waters, 2005-2007

    KAUST Repository

    Schnetzer, Astrid; Jones, Burton; Schaffner, Rebecca A.; Cetinić, Ivona; Fitzpatrick, Elizabeth; Miller, Peter E.; Seubert, Erica L.; Caron, David A.

    2013-01-01

    Harmful algal blooms dominated by the diatom Pseudo-nitzschia spp. have become a perennial but variable event within surface waters near the greater Los Angeles area. Toxic blooms during spring seasons from 2005 to 2007 varied strongly in their overall toxicity and duration. Differences in bloom dynamics were linked to differences in storm-induced river discharge following episodic rain events and coastal upwelling, both major coastal processes that led to the injection of nutrients into coastal surface waters. Heavy river runoff during early 2005, a record-rainfall year, favored a phytoplankton community mainly comprised of algal taxa other than Pseudo-nitzschia. The spring bloom during 2005 was associated with low domoic acid surface concentrations and minor contributions of (mainly) P. delicatissima to the diatom assemblage. In contrast, highly toxic P. australis-dominated blooms during spring seasons of 2006 and 2007 were linked to strong upwelling events. River discharge quotas in 2006 and 2007, in contrast to 2005, fell well below annual averages for the region. Surface toxin levels were linked to colder, more saline (i.e. upwelled) water over the 3-year study, but no such consistent relationship between domoic acid levels and other physiochemical parameters, such as macronutrient concentrations or nutrient ratios, was observed. © The Author 2013. Published by Oxford University Press. All rights reserved.

  5. Coastal upwelling linked to toxic Pseudo-nitzschia australis blooms in Los Angeles coastal waters, 2005-2007

    KAUST Repository

    Schnetzer, Astrid

    2013-06-10

    Harmful algal blooms dominated by the diatom Pseudo-nitzschia spp. have become a perennial but variable event within surface waters near the greater Los Angeles area. Toxic blooms during spring seasons from 2005 to 2007 varied strongly in their overall toxicity and duration. Differences in bloom dynamics were linked to differences in storm-induced river discharge following episodic rain events and coastal upwelling, both major coastal processes that led to the injection of nutrients into coastal surface waters. Heavy river runoff during early 2005, a record-rainfall year, favored a phytoplankton community mainly comprised of algal taxa other than Pseudo-nitzschia. The spring bloom during 2005 was associated with low domoic acid surface concentrations and minor contributions of (mainly) P. delicatissima to the diatom assemblage. In contrast, highly toxic P. australis-dominated blooms during spring seasons of 2006 and 2007 were linked to strong upwelling events. River discharge quotas in 2006 and 2007, in contrast to 2005, fell well below annual averages for the region. Surface toxin levels were linked to colder, more saline (i.e. upwelled) water over the 3-year study, but no such consistent relationship between domoic acid levels and other physiochemical parameters, such as macronutrient concentrations or nutrient ratios, was observed. © The Author 2013. Published by Oxford University Press. All rights reserved.

  6. The Gap in the Current Research on the Link between Health Locus of Control and Multiple Sclerosis: Lessons and Insights from a Systematic Review

    Directory of Open Access Journals (Sweden)

    Nicola Luigi Bragazzi

    2013-01-01

    Full Text Available Multiple sclerosis (MS is a chronic neurological disease whose etiology has not been fully understood yet in detail. Empirical findings show how psychosocial symptoms are very important features of the clinical presentation of MS, having a deep impact on patient's quality of life, and thus psychological coping strategies may play a central role in reducing the burden of the disease and improving patient's satisfaction of life. MS progression and relapses/exacerbations are unpredictable and may depend on factors such as stressor chronicity, frequency, severity, type, and individual patient characteristics such as depression, personality, locus of control (LOC, optimism, and perceived social support. Due to its importance for health-care delivery, rehabilitation, and nursing, here, we make a systematic review on the current state-of-the-art studies concerning the relationship between LOC and MS, according to the PRISMA guidelines, and we assess the quality and the completeness of the studies using the CONSORT instrument, underpinning their limitations, and suggesting how to fill the gap in this research field.

  7. Social Position Influencing the Water Perception Gap Between Local Leaders and Constituents in a Socio-Hydrological System

    Science.gov (United States)

    Haeffner, Melissa; Jackson-Smith, Douglas; Flint, Courtney G.

    2018-02-01

    How well city leaders represent their constituents and meet their needs are key concerns in transitioning to local sustainable water governance. To date, however, there is little research documenting the influence of social position between elected leaders who make policy, career staff water managers who design and operate systems and implement policies, and the members of the public whose individual water use behaviors are important drivers of water sustainability outcomes. In this study, we ask: "How does social position explain variation in water perceptions and concerns between different actors in a socio-hydrological system?" Using a mixed method approach with survey and interview data, we explore the ways that positioning within the governance system, geographic context, and citizen engagement in local government mediate perceptions of the urban water system. Regardless of local biophysical water supply conditions, residents showed most concern about future water shortages and high water costs, while their leaders were consistently most concerned about deteriorating local water infrastructure. Further, constituents who received water-related information directly from public utility mailings or served on community committees and boards had perceptions that were more aligned with leaders' concerns. The importance of social structure over natural and built environments in shaping water issue perceptions underscores the value of social analysis in socio-hydrology studies. Further, practitioners looking to increase consensus for a transition to sustainable water governance might work to develop institutional mechanisms to increase opportunities for water user involvement in local water system governance.

  8. A conceptual model for the analysis of multi-stressors in linked groundwater-surface water systems.

    Science.gov (United States)

    Kaandorp, Vince P; Molina-Navarro, Eugenio; Andersen, Hans E; Bloomfield, John P; Kuijper, Martina J M; de Louw, Perry G B

    2018-06-15

    Groundwater and surface water are often closely coupled and are both under the influence of multiple stressors. Stressed groundwater systems may lead to a poor ecological status of surface waters but to date no conceptual framework to analyse linked multi-stressed groundwater - surface water systems has been developed. In this paper, a framework is proposed showing the effect of groundwater on surface waters in multiple stressed systems. This framework will be illustrated by applying it to four European catchments, the Odense, Denmark, the Regge and Dinkel, Netherlands, and the Thames, UK, and by assessing its utility in analysing the propagation or buffering of multi-stressors through groundwater to surface waters in these catchments. It is shown that groundwater affects surface water flow, nutrients and temperature, and can both propagate stressors towards surface waters and buffer the effect of stressors in space and time. The effect of groundwater on drivers and states depends on catchment characteristics, stressor combinations, scale and management practises. The proposed framework shows how groundwater in lowland catchments acts as a bridge between stressors and their effects within surface waters. It shows water managers how their management areas might be influenced by groundwater, and helps them to include this important, but often overlooked part of the water cycle in their basin management plans. The analysis of the study catchments also revealed a lack of data on the temperature of both groundwater and surface water, while it is an important parameter considering future climate warming. Copyright © 2018. Published by Elsevier B.V.

  9. Ecohydrology of managed ecosystems: Linking rainfall unpredictability, agronomic performance, and sustainable water use

    Science.gov (United States)

    Vico, Giulia; Porporato, Amilcare

    2014-05-01

    The field of ecohydrology, traditionally focusing on natural ecosystems, can offer the necessary quantitative tools to assess and compare the sustainability of agriculture across climates, soil types, crops, and irrigation strategies, including rainfall unpredictability. In particular, irrigation is one of the main strategies to enhance and stabilize agricultural productivity, but represents a cost in terms of often scarce water resources. Here, the sustainability of irrigated and rainfed agriculture is assessed by means of water productivity (defined as the ratio between yield and total supplied water), yields, water requirements, and their variability. These indicators are quantified using a probabilistic description of the soil water balance and crop development. Employing this framework, we interpret changes in water productivity as total water input is altered, in two staple crops (maize and wheat) grown under different soils, climates, and irrigation strategies. Climate change scenarios are explored by using the same approach and altering the rainfall statistics. For a given irrigation strategy, intermediate rainfall inputs leads to the highest variability in yield and irrigation water requirement - it is under these conditions that water management is most problematic. When considering the contrasting needs of limiting water requirements while ensuring adequate yields, micro-irrigation emerges as the most sustainable strategy at the field level, although consideration should be given to its profitability and long-term environmental implications.

  10. Gap-filling of dry weather flow rate and water quality measurements in urban catchments by a time series modelling approach

    DEFF Research Database (Denmark)

    Sandoval, Santiago; Vezzaro, Luca; Bertrand-Krajewski, Jean-Luc

    2016-01-01

    seeks to evaluate the potential of the Singular Spectrum Analysis (SSA), a time-series modelling/gap-filling method, to complete dry weather time series. The SSA method is tested by reconstructing 1000 artificial discontinuous time series, randomly generated from real flow rate and total suspended......Flow rate and water quality dry weather time series in combined sewer systems might contain an important amount of missing data due to several reasons, such as failures related to the operation of the sensor or additional contributions during rainfall events. Therefore, the approach hereby proposed...... solids (TSS) online measurements (year 2007, 2 minutes time-step, combined system, Ecully, Lyon, France). Results show up the potential of the method to fill gaps longer than 0.5 days, especially between 0.5 days and 1 day (mean NSE > 0.6) in the flow rate time series. TSS results still perform very...

  11. Afloat in a Boat: Linking Land Use / Land Cover to the Spatial Evolution of Water Quality along a Blackwater Stream

    Science.gov (United States)

    Neville, J.; Vose, J. M.; Nichols, E. G.; Jass, T. L.; Emanuel, R. E.; McRae, J.

    2016-12-01

    Water quality and land use/land cover (LULC) are linked intimately in many watersheds, although exact relationships are often nonlinear and sometimes complex. Together with watershed topography, LULC can affect water quality in various ways. As such, attributing water quality characteristics to LULC variations (either in space or time) can be difficult. Many studies seek to understand these relationships from a Eulerian reference frame, which typically involves many samples or observations through time at a fixed location. Here we explore an alternative approach to understanding relationships between LULC and water quality that relies on a Lagrangian, or moving, reference frame, in which the effects of LULC and watershed topography on water quality can be observed through a different lens. We studied three reaches of the Lumber River, a blackwater stream in North Carolina's Coastal Plain, to assess relationships between LULC and water quality in a watershed that is a patchwork of agriculture, forests, wetlands and developed land. Our study combines spatially intensive water quality measurements (temperature, specific conductance, dissolved oxygen, pH and nitrate concentration), collected by boat, with geospatial analyses of LULC to understand influences on the spatial evolution of reach-scale water quality. In particular, we investigate relationships between spatial patterns in nitrate and the changing spatial characteristics of the watershed integrated at sampling points along each reach. We also assess relationships between nitrate and other water quality variables, such as pH, temperature, and dissolved oxygen to better understand the potential role of in-stream nutrient processing in observed spatial patterns. This work has implications for the regulation and management of agriculture, wetlands, and forests in a region that has long struggled to balance agriculture, a major economic driver, with water quality, a major concern for recreation and cultural

  12. Gap Resolution

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-25

    Gap Resolution is a software package that was developed to improve Newbler genome assemblies by automating the closure of sequence gaps caused by repetitive regions in the DNA. This is done by performing the follow steps:1) Identify and distribute the data for each gap in sub-projects. 2) Assemble the data associated with each sub-project using a secondary assembler, such as Newbler or PGA. 3) Determine if any gaps are closed after reassembly, and either design fakes (consensus of closed gap) for those that closed or lab experiments for those that require additional data. The software requires as input a genome assembly produce by the Newbler assembler provided by Roche and 454 data containing paired-end reads.

  13. Systems Biology for Smart Crops and Agricultural Innovation: Filling the Gaps between Genotype and Phenotype for Complex Traits Linked with Robust Agricultural Productivity and Sustainability

    Science.gov (United States)

    Pathak, Rajesh Kumar; Gupta, Sanjay Mohan; Gaur, Vikram Singh; Pandey, Dinesh

    2015-01-01

    Abstract In recent years, rapid developments in several omics platforms and next generation sequencing technology have generated a huge amount of biological data about plants. Systems biology aims to develop and use well-organized and efficient algorithms, data structure, visualization, and communication tools for the integration of these biological data with the goal of computational modeling and simulation. It studies crop plant systems by systematically perturbing them, checking the gene, protein, and informational pathway responses; integrating these data; and finally, formulating mathematical models that describe the structure of system and its response to individual perturbations. Consequently, systems biology approaches, such as integrative and predictive ones, hold immense potential in understanding of molecular mechanism of agriculturally important complex traits linked to agricultural productivity. This has led to identification of some key genes and proteins involved in networks of pathways involved in input use efficiency, biotic and abiotic stress resistance, photosynthesis efficiency, root, stem and leaf architecture, and nutrient mobilization. The developments in the above fields have made it possible to design smart crops with superior agronomic traits through genetic manipulation of key candidate genes. PMID:26484978

  14. Changes in water consumption linked to heavy news media coverage of extreme climatic events.

    Science.gov (United States)

    Quesnel, Kimberly J; Ajami, Newsha K

    2017-10-01

    Public awareness of water- and drought-related issues is an important yet relatively unexplored component of water use behavior. To examine this relationship, we first quantified news media coverage of drought in California from 2005 to 2015, a period with two distinct droughts; the later drought received unprecedentedly high media coverage, whereas the earlier drought did not, as the United States was experiencing an economic downturn coinciding with a historic presidential election. Comparing this coverage to Google search frequency confirmed that public attention followed news media trends. We then modeled single-family residential water consumption in 20 service areas in the San Francisco Bay Area during the same period using geospatially explicit data and including news media coverage as a covariate. Model outputs revealed the factors affecting water use for populations of varying demographics. Importantly, the models estimated that an increase of 100 drought-related articles in a bimonthly period was associated with an 11 to 18% reduction in water use. Then, we evaluated high-resolution water consumption data from smart meters, known as advanced metering infrastructure, in one of the previously modeled service areas to evaluate breakpoints in water use trends. Results demonstrated that whereas nonresidential commercial irrigation customers responded to changes in climate, single-family residential customers decreased water use at the fastest rate following heavy drought-related news media coverage. These results highlight the need for water resource planners and decision makers to further consider the importance of effective, internally and externally driven, public awareness and education in water demand behavior and management.

  15. Gap Junctions

    Science.gov (United States)

    Nielsen, Morten Schak; Axelsen, Lene Nygaard; Sorgen, Paul L.; Verma, Vandana; Delmar, Mario; Holstein-Rathlou, Niels-Henrik

    2013-01-01

    Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society. Compr Physiol 2:1981-2035, 2012. PMID:23723031

  16. Linking Flow Regime and Water Quality in Rivers: a Challenge to Adaptive Catchment Management

    Directory of Open Access Journals (Sweden)

    Christer Nilsson

    2008-12-01

    Full Text Available Water quality describes the physicochemical characteristics of the water body. These vary naturally with the weather and with the spatiotemporal variation of the water flow, i.e., the flow regime. Worldwide, biota have adapted to the variation in these variables. River channels and their riparian zones contain a rich selection of adapted species and have been able to offer goods and services for sustaining human civilizations. Many human impacts on natural riverine environments have been destructive and present opportunities for rehabilitation. It is a big challenge to satisfy the needs of both humans and nature, without sacrificing one or the other. New ways of thinking, new policies, and institutional commitment are needed to make improvements, both in the ways water flow is modified in rivers by dam operations and direct extractions, and in the ways runoff from adjacent land is affected by land-use practices. Originally, prescribed flows were relatively static, but precepts have been developed to encompass variation, specifically on how water could be shared over the year to become most useful to ecosystems and humans. A key aspect is how allocations of water interact with physicochemical variation of water. An important applied question is how waste releases and discharge can be managed to reduce ecological and sanitary problems that might arise from inappropriate combinations of flow variation and physicochemical characteristics of water. We review knowledge in this field, provide examples on how the flow regime and the water quality can impact ecosystem processes, and conclude that most problems are associated with low-flow conditions. Given that reduced flows represent an escalating problem in an increasing number of rivers worldwide, managers are facing enormous challenges.

  17. Analysis of environmental setting, surface-water and groundwater data, and data gaps for the Citizen Potawatomi Nation Tribal Jurisdictional Area, Oklahoma, through 2011

    Science.gov (United States)

    Andrews, William J.; Harich, Christopher R.; Smith, S. Jerrod; Lewis, Jason M.; Shivers, Molly J.; Seger, Christian H.; Becker, Carol J.

    2013-01-01

    in more urbanized areas. Much of the water in the area is of good quality, though some parts of this area have water quality impaired by very hard surface water and groundwater; large chloride concentrations in some smaller streams; relatively large concentrations of nutrients and counts of fecal-indicator bacteria in the North Canadian River; and chloride, iron, manganese, and uranium concentrations that exceed primary or secondary drinking-water standards in water samples collected from small numbers of wells. Substantial amounts of hydrologic and water-quality data have been collected in much of this area, but there are gaps in those data caused by relatively few streamflow-gaging stations, uneven distribution of surface-water quality sampling sites, lack of surface-water quality sampling at high-flow and low-flow conditions, and lack of a regularly measured and sampled groundwater network. This report summarizes existing water-use, climatic, geographic, hydrologic, and water-quality data and describes several means of filling gaps in hydrologic data for this area.

  18. Linking marine resources to ecotonal shifts of water uptake by terrestrial dune vegetation.

    Science.gov (United States)

    Greaver, Tara L; Sternberg, Leonel L da S

    2006-09-01

    As evidence mounts that sea levels are rising, it becomes increasingly important to understand the role of ocean water within terrestrial ecosystem dynamics. Coastal sand dunes are ecosystems that occur on the interface of land and sea. They are classic ecotones characterized by zonal distribution of vegetation in response to strong gradients of environmental factors from the ocean to the inland. Despite the proximity of the dune ecosystem to the ocean, it is generally assumed that all vegetation utilizes only freshwater and that water sources do not change across the ecotone. Evidence of ocean water uptake by vegetation would redefine the traditional interpretation of plant-water relations in the dune ecosystem and offer new ideas for assessing maritime influences on function and spatial distribution of plants across the dune. The purpose of this study was to identify sources of water (ocean, ground, and rain) taken up by vegetation using isotopic analysis of stem water and to evaluate water uptake patterns at the community level based on the distribution and assemblage of species. Three coastal dune systems located in southern Florida, USA, and the Bahamian bank/platform system were investigated. Plant distributions across the dune were zonal for 61-94% of the 18 most abundant species at each site. Species with their highest frequency on the fore dune (nearest the ocean) indicate ocean water uptake as evidenced by delta 18O values of stem water. In contrast, species most frequent in the back dune show no evidence of ocean water uptake. Analysis of species not grouped by frequency, but instead sampled along a transect from the ocean toward the inland, indicates that individuals from the vegetation assemblage closest to the ocean had a mixed water-harvesting strategy characterized by plants that may utilize ocean, ground-, and/or rainwater. In contrast, the inland vegetation relies mostly on rainwater. Our results show evidence supporting ocean water use by dune

  19. First Detection of Water Ice and Organics on an Asteroid: A Possible Link to the Origin of Earth's Water

    Science.gov (United States)

    Hargrove, Kelsey D.; Campins, H.; Pinilla-Alonso, N.; Howell, E. S.; Kelley, M. S.; Licandro, J.; Mothédiniz, T.; Fernández, Y.; Ziffer, J.

    2010-05-01

    We report the detection of water ice and organics on the surface of asteroid 24 Themis. Our rotationally-resolved infrared (2-4 µm) spectra of this asteroid indicate that the ice and organics are widespread on its surface. The spectral difference with other asteroids observed in the same manner, makes 24 Themis unique so far. Our identification of water ice and organic compounds on this asteroid agrees with independent results (Rivkin and Emery 2010). At first glance, the presence of any surface ice on 24 Themis, particularly over a significant fraction of its surface, is puzzling because of the instability for exposed water ice at Themis's heliocentric distance ( 3.2 AU). Nevertheless, there are several possible sources for this unstable ice and identifying them is likely to be diagnostic of other processes on primitive asteroids. The presence of water ice on 24 Themis supports the idea that ice sublimation drives the cometary activity in two small members of the Themis dynamical family, labeled "Main Belt comets” by Hsieh and Jewitt (2006). It also helps to address other relevant questions, such as, how abundant is water ice in the outer asteroid belt and where was the "snow” line when the solar system formed? The answers to these questions could transform current views of primitive asteroids, delivery of water and organic molecules to Earth, and models of Solar System formation. This research was published in the April 29, 2010 issue of the journal Nature. Hargrove and Campins are visiting astronomers at the Infrared Telescope Facility (IRTF), which is operated by the University of Hawaii under Cooperative Agreement no. NCC 5-538 with the National Aeronautics and Space Administration

  20. The cross-linking influence of electromagnetic radiation on water-soluble polyacrylan compositions with biopolymers

    Directory of Open Access Journals (Sweden)

    B. Grabowska

    2009-01-01

    Full Text Available The results of examinations of the cross-linking influence of electromagnetic radiation - in a microwave range – on polyacrylancompositions with biopolymers, are presented in the hereby paper. The cross-linking process of the tested compositions was determined on the basis of the FT-IR spectroscopic methods. It was shown that microwave operations can lead to the formation of new cross-linkedstructures with strong covalent bonds. The adsorption process and formation of active centres in polymer molecules as well as in highsilica sand were found due to microwave radiations. In this process hydroxyl groups (-OH - present in a polymer - and silane groups (Si- O-H - present in a matrix - are mainly taking part. Spectroscopic and strength tests performed for the system: biopolymer binding agent – matrix indicate that the microwave radiation can be applied for hardening moulding sands with biopolymer binders.

  1. Extreme diving behaviour in devil rays links surface waters and the deep ocean

    KAUST Repository

    Thorrold, Simon R.; Afonso, Pedro; Fontes, Jorge; Braun, Camrin D.; Santos, Ricardo S.; Skomal, Gregory B.; Berumen, Michael L.

    2014-01-01

    Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food webs containing a suite

  2. Linking otolith microchemistry and surface water contamination from natural gas mining.

    Science.gov (United States)

    Keller, David H; Zelanko, Paula M; Gagnon, Joel E; Horwitz, Richard J; Galbraith, Heather S; Velinsky, David J

    2018-09-01

    Unconventional natural gas drilling and the use of hydraulic fracturing technology have expanded rapidly in North America. This expansion has raised concerns of surface water contamination by way of spills and leaks, which may be sporadic, small, and therefore difficult to detect. Here we explore the use of otolith microchemistry as a tool for monitoring surface water contamination from generated waters (GW) of unconventional natural gas drilling. We exposed Brook Trout in the laboratory to three volumetric concentrations of surrogate generated water (SGW) representing GW on day five of drilling. Transects across otolith cross-sections were analyzed for a suite of elements by LA-ICP-MS. Brook Trout exposed to a 0.01-1.0% concentration of SGW for 2, 15, and 30 days showed a significant (p waters and provide support for the use of this technique in natural habitats. To our knowledge, this is the first demonstration of how trace elements in fish otoliths may be used to monitor for surface water contamination from GW. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Reflexive Land and Water Management in Iran: Linking Technology, Governance and Culture. Part 1: Land and Water Management Paradigms

    NARCIS (Netherlands)

    Balali, M.R.; Keulartz, F.W.J.; Korthals, M.J.J.A.A.

    2011-01-01

    In order to examine the possibilities for sustainable land and water management in Iran, this research was carried out with two types of research and their combinations, i.e. theoretical and empirical research during 2005- 2009. In the theoretical part, which is the scope of this paper, the

  4. Precipitation isotopes link regional climate patterns to water supply in a tropical mountain forest, eastern Puerto Rico

    Science.gov (United States)

    Scholl, Martha A.; Murphy, Sheila F.

    2014-05-01

    Like many mountainous areas in the tropics, watersheds in the Luquillo Mountains of eastern Puerto Rico have abundant rainfall and stream discharge and provide much of the water supply for the densely populated metropolitan areas nearby. Projected changes in regional temperature and atmospheric dynamics as a result of global warming suggest that water availability will be affected by changes in rainfall patterns. It is essential to understand the relative importance of different weather systems to water supply to determine how changes in rainfall patterns, interacting with geology and vegetation, will affect the water balance. To help determine the links between climate and water availability, stable isotope signatures of precipitation from different weather systems were established to identify those that are most important in maintaining streamflow and groundwater recharge. Precipitation stable isotope values in the Luquillo Mountains had a large range, from fog/cloud water with δ2H, δ18O values as high as +12 ‰, -0.73 ‰ to tropical storm rain with values as low as -127 ‰, -16.8 ‰. Temporal isotope values exhibit a reverse seasonality from those observed in higher latitude continental watersheds, with higher isotopic values in the winter and lower values in the summer. Despite the higher volume of convective and low-pressure system rainfall, stable isotope analyses indicated that under the current rainfall regime, frequent trade -wind orographic showers contribute much of the groundwater recharge and stream base flow. Analysis of rain events using 20 years of 15 -minute resolution data at a mountain station (643 m) showed an increasing trend in rainfall amount, in agreement with increased precipitable water in the atmosphere, but differing from climate model projections of drying in the region. The mean intensity of rain events also showed an increasing trend. The determination of recharge sources from stable isotope tracers indicates that water supply

  5. Demand Supply Gap in Urban Water Supply and Sanitary Services- A Case Study of Mangalore City Corporation Area

    OpenAIRE

    Nagendra; Suresh

    2009-01-01

    Today, some 1.1 billion people in developing countries have inadequate access to water, and 2.6 billion lack basic sanitations. These twin deficits were rooted in institutions and political choices, not in water’s availability. Household water requirements represent a tiny fraction of water use, usually less than 5% of the total, but there is tremendous inequality in access to clean water and to sanitation at a household level. In high-income areas of cities in Asia, Latin America and Sub-Sah...

  6. Mythic gaps

    Directory of Open Access Journals (Sweden)

    William Hansen

    2014-11-01

    Full Text Available Different kinds of omissions sometimes occur, or are perceived to occur, in traditional narratives and in tradition-inspired literature. A familiar instance is when a narrator realizes that he or she does not fully remember the story that he or she has begun to tell, and so leaves out part of it, which for listeners may possibly result in an unintelligible narrative. But many instances of narrative gap are not so obvious. From straightforward, objective gaps one can distinguish less-obvious subjective gaps: in many cases narrators do not leave out anything crucial or truly relevant from their exposition, and yet readers perceive gaps and take steps to fill them. The present paper considers four examples of subjective gaps drawn from ancient Greek literature (the Pandora myth, ancient Roman literature (the Pygmalion legend, ancient Hebrew literature (the Joseph legend, and early Christian literature (the Jesus legend. I consider the quite varied ways in which interpreters expand the inherited texts of these stories, such as by devising names, manufacturing motives, creating backstories, and in general filling in biographical ellipses. Finally, I suggest an explanation for the phenomenon of subjective gaps, arguing that, despite their variety, they have a single cause.

  7. Linking climate change to water provision: greywater treatment by constructed wetlands

    Science.gov (United States)

    Qomariyah, S.; Ramelan, AH; Setyono, P.; Sobriyah

    2018-03-01

    Climate change has been felt to take place in Indonesia, causing the temperature to increase, additional drought with more moisture evaporates from rivers, lakes, and other bodies of water, and intense rainfall in a shorter rainy season. One of the major concerns is the risk of severe drought leading to water shortages. It will affect water supply and agriculture yields. As a country extremely vulnerable to the climate change, Indonesia must adapt to the serious environmental issues. This paper aims to offer an effort of water provision by recycling and reusing of greywater applying constructed wetland systems. The treated greywater is useful as water provision for non-consumptive uses. A recent experiment was conducted on a household yard using a single horizontal subsurface flow type of constructed wetland. The experiments demonstrated that the constructed wetland systems reduced effectively the pollutants of TSS, BOD, COD, and detergent to the level that are compliant with regulatory standards. The constructed wetland has been established for almost two years however the system still works properly.

  8. Linking seasonal surface water dynamics with methane emissions and export from small, forested wetlands

    Science.gov (United States)

    Hondula, K. L.; Palmer, M.

    2017-12-01

    One of the biggest uncertainties about global methane sources and sinks is attributed to uncertainties regarding wetland area and its dynamics. This is exacerbated by confusion over the role of small, shallow water bodies like Delmarva bay wetlands that could be categorized as both wetlands and ponds. These small inland water bodies are often poorly quantified due to their size, closed forest canopies, and inter- and intra-annual variability in surface water extent. We are studying wetland-rich areas on the Delmarva Peninsula in the U.S. mid-Atlantic to address this uncertainty at the scale of individual wetland ecosystems ( 1m depth). We estimated the size and temporal variability of the methane emissions source area by combining these measurements with daily estimates of the extent of surface water inundation derived from water level monitoring and a high-resolution digital elevation model. This knowledge is critical for informing land use decisions (e.g. restoring wetlands specifically for climate mitigation), the jurisdiction of environmental policies in the US, and for resolving major outstanding discrepancies in our understanding of the global methane budget.

  9. Modeling Sustainability of Water, Environment, Livelihood, and Culture in Traditional Irrigation Communities and Their Linked Watersheds

    Directory of Open Access Journals (Sweden)

    Kenneth Boykin

    2012-11-01

    Full Text Available Water scarcity, land use conversion and cultural and ecosystem changes threaten the way of life for traditional irrigation communities of the semi-arid southwestern United States. Traditions are strong, yet potential upheaval is great in these communities that rely on acequia irrigation systems. Acequias are ancient ditch systems brought from the Iberian Peninsula to the New World over 400 years ago; they are simultaneously gravity flow water delivery systems and shared water governance institutions. Acequias have survived periods of drought and external shocks from changing economics, demographics, and resource uses. Now, climate change and urbanization threaten water availability, ecosystem functions, and the acequia communities themselves. Do past adaptive practices hold the key to future sustainability, or are new strategies required? To explore this issue we translated disciplinary understanding into a uniform format of causal loop diagrams to conceptualize the subsystems of the entire acequia-based human-natural system. Four subsystems are identified in this study: hydrology, ecosystem, land use/economics, and sociocultural. Important linkages between subsystems were revealed as well as variables indicating community cohesion (e.g., total irrigated land, intensity of upland grazing, mutualism. Ongoing work will test the conceptualizations with field data and modeling exercises to capture tipping points for non-sustainability and thresholds for sustainable water use and community longevity.

  10. Method of cross-linking polyvinyl alcohol and other water soluble resins

    Science.gov (United States)

    Phillipp, W. H.; May, C. E.; Hsu, L. C.; Sheibley, D. W. (Inventor)

    1980-01-01

    A self supporting sheet structure comprising a water soluble, noncrosslinked polymer such as polyvinyl alcohol which is capable of being crosslinked by reaction with hydrogen atom radicals and hydroxyl molecule radicals is contacted with an aqueous solution having a pH of less than 8 and containing a dissolved salt in an amount sufficient to prevent substantial dissolution of the noncrosslinked polymer in the aqueous solution. The aqueous solution is then irradiated with ionizing radiation to form hydrogen atom radicals and hydroxyl molecule radicals and the irradiation is continued for a time sufficient to effect crosslinking of the water soluble polymer to produce a water insoluble polymer sheet structure. The method has particular application in the production of battery separators and electrode envelopes for alkaline batteries.

  11. Link between DOC in near surface peat and stream water in an upland catchment.

    Science.gov (United States)

    Clark, Joanna M; Lane, Stuart N; Chapman, Pippa J; Adamson, John K

    2008-10-15

    Hydrologic transport of dissolved organic carbon (DOC) from peat soils may differ to organo-mineral soils in how they responded to changes in flow, because of differences in soil profile and hydrology. In well-drained organo-mineral soils, low flow is through the lower mineral layer where DOC is absorbed and high flow is through the upper organic layer where DOC is produced. DOC concentrations in streams draining organo-mineral soils typically increase with flow. In saturated peat soils, both high and low flows are through an organic layer where DOC is produced. Therefore, DOC in stream water draining peat may not increase in response to changes in flow as there is no switch in flow path between a mineral and organic layer. To verify this, we conducted a high-resolution monitoring study of soil and stream water at an upland peat catchment in northern England. Our data showed a strong positive correlation between DOC concentrations at -1 and -5 cm depth and stream water, and weaker correlations between concentrations at -20 to -50 cm depth and stream water. Although near surface organic material appears to be the key source of stream water DOC in both peat and organo-mineral soils, we observed a negative correlation between stream flow and DOC concentrations instead of a positive correlation as DOC released from organic layers during low and high flow was diluted by rainfall. The differences in DOC transport processes between peat and organo-mineral soils have different implications for our understanding of long-term changes in DOC exports. While increased rainfall may cause an increase in DOC flux from peat due to an increase in water volume, it may cause a decrease in concentrations. This response is contrary to expected changes in DOC exports from organo-mineral soils, where increase rainfall is likely to result in an increase in flux and concentration.

  12. The link between water quality and tidal marshes in a highly impacted estuary.

    Science.gov (United States)

    Meire, Patrick; Maris, Tom; van Damme, Stefan; Jacobs, Sander; Cox, Tom; Struyf, Eric

    2010-05-01

    The Schelde estuary is one of the most heavily impacted estuaries in Europe. During several decades, untreated waste water from large cities (e.g. Brussels, Antwerp, Valenciennes, Lille) and industries was discharged in the river. As a result, the Schelde estuary has the reputation of being one of the most polluted estuaries in Europe. For a long time (approx. 1950 - 1995) all forms of higher life (macro-invertebrates and fish) were absent in the fresh and brackish parts of the estuary. Due to European legislation, a large part of the sewage water is now treated resulting in a significant recovery of water quality in the estuary. However, next to water quality, the estuary also suffered serious habitat losses during the last decades, mostly due to economic development and changing hydrological conditions causing more erosion. Over the last fifteen years, the management of the estuary has changed fundamentally. It is now more and more focused on the restoration of ecosystem services. In this presentation we will document the changes in water quality over the last 50 years and summarize recent work on the role of tidal marshes on water quality within the freshwater part of the Schelde estuary. Our results stress the important of taking into account ecosystem services and habitat restoration for long-term estuarine management. .After decades of high inorganic nutrient concentrations and recurring anoxia and hypoxia, we observed a paradoxical increase in chlorophyll-a concentrations with decreasing nutrient inputs, indicating a regime shift. Our results indicate that the recovery of a hypereutrophied systems towards a classical eutrophied state, needs the reduction of waste loads below certain thresholds. Paradoxically, phytoplankton production was inhibited by high ammonia or low oxygen concentrations. The system state change is accompanied by large fluctuations in oxygen concentrations. The improved water quality resulted in a remarkable recovery of different groups

  13. Combining integrated models and participatory methods to quantify water and agricultural trade-offs linked to different rural development scenarios

    Science.gov (United States)

    Rivas, David; Willaarts, Barbara; García, Ángel de Miguel; Tarquis, Ana Maria

    2017-04-01

    This study explores the water and agricultural tradeoffs linked to three different rural development scenarios in the Cega-Eresma-Adaja basin (CEA) in Central Spain. Agriculture is a key socioeconomic activity in CEA, and nearly 44% of the basin is devoted to croplands and pastures. Irrigated agriculture accounts for 12% of the cropland area and is currently using over 84% of available water resources. To define the three scenarios for CEA, we conducted a workshop with local stakeholders to infer how contrasting evolutions of EU agricultural, water and environmental policies could affect the local land use and agricultural management using participatory mapping techniques. The three scenarios reflect 1) a business as usual (BAU) rural development; 2) a land sharing strategy (LSH); and 3) a land sparing (LSP) situation. The integrated Soil Water Assessment Tool (SWAT) was used to model the changes in water use (hm^3/year) and agricultural productivity (ton/year) under each scenario. To account for changes in agricultural land use and management, the model integrates a large set of agricultural patterns obtained from combining high resolution remote sensing images (20m x 20m) for the years 2011-2015, agricultural productivity from survey by municipality and land use information obtained from the national map SIOSE2011 (1:50.000). Model calibration and sensitivity analysis were performed using SWAT-CUP/SUFI2 The period of the years 2005 to 2008 were used for parameter calibration and validation period extending between 2009 and 2014. The predicted daily streamflow presents a correlation coefficient of 0.76 and a NS coefficient of 0.81. The preliminary results reveal that under a BAU and a LSP scenario agricultural production and water demand will increase significantly (>25%) despite the improvements in water use efficiency and agricultural productivity. Under these scenarios, allocated water is likely to exceed the natural renewable water resources compromising the

  14. Are nitrate exports in stream water linked to nitrogen fluxes in decomposing foliar litter?

    Science.gov (United States)

    Kathryn B. Piatek; Mary Beth. Adams

    2011-01-01

    The central hardwood forest receives some of the highest rates of atmospheric nitrogen (N) deposition, which results in nitrate leaching to surface waters. Immobilization of N in foliar litter during litter decomposition represents a potential mechanism for temporal retention of atmospherically deposited N in forest ecosystems. When litter N dynamics switch to the N-...

  15. Biodiversity links above and below the marine sediment-water interface that may influence community stability

    NARCIS (Netherlands)

    Austen, M.C.; Lambshead, P.J.D.; Hutchings, P.; Boucher, G.; Snelgrove, P.V.R.; Heip, C.H.R.; King, G.; Koike, I.; Smith, C.

    2002-01-01

    Linkages across the sediment-water interface (SWI) between biodiversity and community stability appear to exist but are very poorly studied. Processes by which changes in biodiversity could affect stability on the other side of the SWI include carbon transfer during feeding, decomposition of organic

  16. In vitro degradation of dermal sheep collagen cross-linked using a water-soluble carbodiimide

    NARCIS (Netherlands)

    Damink, LHHO; Dijkstra, PJ; vanLuyn, MJA; vanWachem, PB; Nieuwenhuis, P; Feijen, J

    Bacterial collagenase was used to study the susceptibility of dermal sheep collagen (DSC) cross-inked with a mixture of the water-soluble carbodiimide 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide (EIN-DSC) towards enzymatic degradation. Contrary to

  17. Comment on 'Water footprint of marine protein consumption—aquaculture's link to agriculture'

    NARCIS (Netherlands)

    Troell, M.; Metian, M.; Beveridge, M.; Verdegem, M.C.J.; Deutsch, L.

    2014-01-01

    In their article ‘Freshwater savings from marine protein consumption’ (2014 Environ. Res. Lett. 9 014005), Gephart and her colleagues analyzed how consumption of marine animal protein rather than terrestrial animal protein leads to reduced freshwater allocation. They concluded that future water

  18. UV radiation and natural fluorescence linked primary production in Antarctic waters

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; KrishnaKumari, L.; Bhattathiri, P.M.A.; Chandramohan, D.

    Primary productivity and chlorophyll values have been measured using an underwater profiling radiometer for the first time in the waters around Indian Antarctic Station (70°46'S & 11°44'E) in the summer of 1994. The profiles include natural...

  19. Linking Health Concepts in the Assessment and Evaluation of Water Distribution Systems

    Science.gov (United States)

    Karney, Bryan W.; Filion, Yves R.

    2005-01-01

    The concept of health is not only a specific criterion for evaluation of water quality delivered by a distribution system but also a suitable paradigm for overall functioning of the hydraulic and structural components of the system. This article views health, despite its complexities, as the only criterion with suitable depth and breadth to allow…

  20. Linking water management to spatial development: impact from EU to local level

    NARCIS (Netherlands)

    Knaap, van der W.G.M.

    2013-01-01

    The co-operation between water managers and spatial planners depends heavily on its basic element: competing interests. Aspects that shapes the co-operation and define its effectiveness are language (discipline related jargon), contracts, trust, personal competences, policy tuning & policy

  1. Physiological Plasticity to Water Flow Habitat in the Damselfish, Acanthochromis polyacanthus: Linking Phenotype to Performance

    Science.gov (United States)

    Binning, Sandra A.; Ros, Albert F. H.; Nusbaumer, David; Roche, Dominique G.

    2015-01-01

    The relationships among animal form, function and performance are complex, and vary across environments. Therefore, it can be difficult to identify morphological and/or physiological traits responsible for enhancing performance in a given habitat. In fishes, differences in swimming performance across water flow gradients are related to morphological variation among and within species. However, physiological traits related to performance have been less well studied. We experimentally reared juvenile damselfish, Acanthochromis polyacanthus, under different water flow regimes to test 1) whether aspects of swimming physiology and morphology show plastic responses to water flow, 2) whether trait divergence correlates with swimming performance and 3) whether flow environment relates to performance differences observed in wild fish. We found that maximum metabolic rate, aerobic scope and blood haematocrit were higher in wave-reared fish compared to fish reared in low water flow. However, pectoral fin shape, which tends to correlate with sustained swimming performance, did not differ between rearing treatments or collection sites. Maximum metabolic rate was the best overall predictor of individual swimming performance; fin shape and fish total length were 3.3 and 3.7 times less likely than maximum metabolic rate to explain differences in critical swimming speed. Performance differences induced in fish reared in different flow environments were less pronounced than in wild fish but similar in direction. Our results suggest that exposure to water motion induces plastic physiological changes which enhance swimming performance in A. polyacanthus. Thus, functional relationships between fish morphology and performance across flow habitats should also consider differences in physiology. PMID:25807560

  2. Exergy analysis of a system using a chemical heat pump to link a supercritical water-cooled nuclear reactor and a thermochemical water splitting cycle

    International Nuclear Information System (INIS)

    Granovskii, M.; Dincer, I.; Rosen, M. A.; Pioro, I

    2007-01-01

    The power generation efficiency of nuclear plants is mainly determined by the permissible temperatures and pressures of the nuclear reactor fuel and coolants. These parameters are limited by materials properties and corrosion rates and their effect on nuclear reactor safety. The advanced materials for the next generation of CANDU reactors, which employ steam as a coolant and heat carrier, permit the increased steam parameters (outlet temperature up to 625 degree C and pressure of about 25 MPa). Supercritical water-cooled (SCW) nuclear power plants are expected to increase the power generation efficiency from 35 to 45%. Supercritical water-cooled nuclear reactors can be linked to thermochemical water splitting cycles for hydrogen production. An increased steam temperature from the nuclear reactor makes it also possible to utilize its energy in thermochemical water splitting cycles. These cycles are considered by many as one of the most efficient ways to produce hydrogen from water and to have advantages over traditional low-temperature water electrolysis. However, even lower temperature water splitting cycles (Cu-Cl, UT-3, etc.) require a heat supply at the temperatures over 550-600 degree C. A sufficient increase in the heat transfer from the nuclear reactor to a thermochemical water splitting cycle, without jeopardizing nuclear reactor safety, might be effectively achieved by application of a heat pump which increases the temperature the heat supplied by virtue of a cyclic process driven by mechanical or electrical work. A high temperature chemical heat pump which employs the reversible catalytic methane conversion reaction is proposed. The reaction shift from exothermic to endothermic and back is achieved by a change of the steam concentration in the reaction mixture. This heat pump, coupled with a SCW nuclear plant on one side and thermochemical water splitting cycle on the other, increases the temperature level of the 'nuclear' heat and, thus, the intensity of

  3. Absorbed Pb2+ and Cd2+ Ions in Water by Cross-Linked Starch Xanthate

    Directory of Open Access Journals (Sweden)

    Kai Feng

    2017-01-01

    Full Text Available A cross-linked starch xanthate was prepared by graft copolymerization of acrylamide and sodium acrylate onto starch xanthate using potassium persulfate and sodium hydrogen sulfite initiating system and N,N′-methylenebisacrylamide as a cross-linker. As this kind of cross-linked potato starch xanthate can effectively absorb heavy metal ions, it was dispersed in aqueous solutions of divalent heavy metal ions (Pb2+ and Cd2+ to investigate their absorbency by the polymer. Factors that can influence absorbency were investigated, such as the ratio of matrix to monomers, the amount of initiator and cross-linker, pH, and the concentration of metal ions. Results were reached and conclusion was drawn that the best synthetic conditions for the polymer adsorbing Pb2+ and Cd2+ were as follows: the quality ratio of matrix to monomers was 1 : 12 and 1 : 11, the amount of initiator was 2.4% and 3.2% of matrix, and the amount of cross-linker was 12 mg and 13 mg. When the initial concentration of ions was 10 mg/L, the highest quantities of adsorption of Pb2+ and Cd2+ were 47.11 mg/g and 36.55 mg/g. Adsorption mechanism was discussed by using Fourier transform infrared (FTIR spectroscopy, X-ray diffraction (XRD, scanning electron microscope (SEM, Energy Dispersive X-Ray Spectroscopy (EDS test, and adsorption kinetic simulation.

  4. Novel indirect enzyme-linked immunosorbent assay (ELISA) method to detect Total E. coli in water environment

    International Nuclear Information System (INIS)

    Wang Na; He Miao; Shi Hanchang

    2007-01-01

    In order to establish ELISA (enzyme-linked immunosorbent assay) method to detect Total E. coli in water environment, E. coli multi-characters antigens in water environment were prepared according to the characters of kinds of E. coli serotypes, including antigen of whole cell, antigen of disrupted whole cell, somatic antigen, flagellar antigen and fimbrial antigen. Total E. coli polyclonal antibodies were obtained from the New Zealand rabbits immunized with these five antigens, respectively. Antibodies generated in this research are with high titers and good purity, can conjugate with antigens, specifically, stably and strongly. Indirect ELISA shows the titers of antibody of whole cell and antibody of disrupted whole cell are both over 1 x 10 5 . The cross-reactivity of the antibody is from 12 to 30% which indicate the specificity of the antibody against Total E. coli. Based on these antibodies, we established indirect ELISA method to detect Total E. coli in water environment. The matrix effects were studied and the results show that there is no significant influence by all the factors. The ELISA result shows that the detection limitation could be 10 4 CFU (colony forming units) L -1 . The indirect ELISA method developed in this study is well suited for Total E. coli analysis in real water samples as a rapid screen method

  5. Enhancement of water retention by cross-linked carboxymethylcellulose through polystyrene grafting or γ irradiation

    International Nuclear Information System (INIS)

    Bhattacharjee, S.S.; Perlin, A.S.

    1975-01-01

    The absorbency and retention characteristics of crosslinked carboxymethylcellulose (CLCMC) with respect to water and saline can be substantially improved by two different treatments. One treatment involves γ-radioinduced grafting of polystyrene onto fibers of CLCMC. At a critical level of grafting (approximately 25 percent) the retentive capacity of the fibers is almost doubled. Particularly noteworthy is the sharp increase that follows an initial drop in retentivity. It is concluded the polystyrene becomes associated preferentially with residual ordered regions of the CLCMC macromolecule, through the localization of free radicals in these regions. A second means for enhancing the water and saline retention value of CLCMC, consists of subjecting the material to gamma irradiation from a 60 Co source. Dosages used have ranged from 1.0 to 4.8 megarads (MR), depending on the degree of substitution of the initial carboxymethylcellulose. (JGB)

  6. Linking quantitative microbial risk assessment and epidemiological data: informing safe drinking water trials in developing countries.

    Science.gov (United States)

    Enger, Kyle S; Nelson, Kara L; Clasen, Thomas; Rose, Joan B; Eisenberg, Joseph N S

    2012-05-01

    Intervention trials are used extensively to assess household water treatment (HWT) device efficacy against diarrheal disease in developing countries. Using these data for policy, however, requires addressing issues of generalizability (relevance of one trial in other contexts) and systematic bias associated with design and conduct of a study. To illustrate how quantitative microbial risk assessment (QMRA) can address water safety and health issues, we analyzed a published randomized controlled trial (RCT) of the LifeStraw Family Filter in the Congo. The model accounted for bias due to (1) incomplete compliance with filtration, (2) unexpected antimicrobial activity by the placebo device, and (3) incomplete recall of diarrheal disease. Effectiveness was measured using the longitudinal prevalence ratio (LPR) of reported diarrhea. The Congo RCT observed an LPR of 0.84 (95% CI: 0.61, 1.14). Our model predicted LPRs, assuming a perfect placebo, ranging from 0.50 (2.5-97.5 percentile: 0.33, 0.77) to 0.86 (2.5-97.5 percentile: 0.68, 1.09) for high (but not perfect) and low (but not zero) compliance, respectively. The calibration step provided estimates of the concentrations of three pathogen types (modeled as diarrheagenic E. coli, Giardia, and rotavirus) in drinking water, consistent with the longitudinal prevalence of reported diarrhea measured in the trial, and constrained by epidemiological data from the trial. Use of a QMRA model demonstrated the importance of compliance in HWT efficacy, the need for pathogen data from source waters, the effect of quantifying biases associated with epidemiological data, and the usefulness of generalizing the effectiveness of HWT trials to other contexts. © 2012 American Chemical Society

  7. Identifying factors linked to the occurrence of alien gastropods in isolated woodland water bodies

    Science.gov (United States)

    Spyra, Aneta; Strzelec, Małgorzata

    2014-03-01

    Biological invasions are a significant component of human-caused global change and is widely regarded as one of the main threats to natural biodiversity. Isolated anthropogenic water bodies created in the areas that are deprived of natural freshwater habitats allow the survival and reproduction of alien species on newly settled sites. They are often small with water level fluctuations causing frequent environmental disturbances. The colonisation success may be the result of the rate of their degradation. The aims of the study were to determine the environmental conditions that affect the existence of alien species of gastropods in this type of aquatic environment and to examine whether the occurrence of non-native species affects the community structure of the native species. This study made it possible to group woodland ponds according to the occurrence of the three invasive species in snail communities and discuss the environmental conditions present in these pond types. Analysis of water properties emphasised the distinctiveness of the selected pond types. In ponds of the Potamopyrgus antipodarum type, we found the highest values of some parameters mainly hardness, conductivity, and content of calcium and chlorides, in contrast with the Physella acuta type, which were characterised by the lowest values except for phosphates and nitrites. In the Ferrissia fragilis type, we found the highest nitrate content. Data on the occurrence of alien species in different water environments play an important role in actions which are taken to prevent new invasions and spread of non-native species as well as to reduce future impacts of invaders.

  8. Growth decline linked to warming-induced water limitation in hemi-boreal forests.

    Directory of Open Access Journals (Sweden)

    Xiuchen Wu

    Full Text Available Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii, sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

  9. Growth decline linked to warming-induced water limitation in hemi-boreal forests.

    Science.gov (United States)

    Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A; Badmaeva, Natalya K; Sandanov, Denis V

    2012-01-01

    Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii), sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year) over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

  10. Linking plant functional trait plasticity and the large increase in forest water use efficiency

    Science.gov (United States)

    Mastrotheodoros, Theodoros; Pappas, Christoforos; Molnar, Peter; Burlando, Paolo; Keenan, Trevor F.; Gentine, Pierre; Gough, Christopher M.; Fatichi, Simone

    2017-09-01

    Elevated atmospheric CO2 concentrations are expected to enhance photosynthesis and reduce stomatal conductance, thus increasing plant water use efficiency. A recent study based on eddy covariance flux observations from Northern Hemisphere forests showed a large increase in inherent water use efficiency (IWUE). Here we used an updated version of the same data set and robust uncertainty quantification to revisit these contemporary IWUE trends. We tested the hypothesis that the observed IWUE increase could be attributed to interannual trends in plant functional traits, potentially triggered by environmental change. We found that IWUE increased by 1.3% yr-1, which is less than previously reported but still larger than theoretical expectations. Numerical simulations with the Tethys-Chloris ecosystem model using temporally static plant functional traits cannot explain this increase. Simulations with plant functional trait plasticity, i.e., temporal changes in model parameters such as specific leaf area and maximum Rubisco capacity, match the observed trends in IWUE. Our results show that trends in plant functional traits, equal to 1.0% yr-1, can explain the observed IWUE trends. Thus, at decadal or longer time scales, trait plasticity could potentially influence forest water, carbon, and energy fluxes with profound implications for both the monitoring of temporal changes in plant functional traits and their representation in Earth system models.

  11. Linking community-based monitoring to water policy: Perceptions of citizen scientists.

    Science.gov (United States)

    Carlson, Tyler; Cohen, Alice

    2018-05-05

    This paper examines the relationships between Community-Based Water Monitoring (CBM) and government-led water initiatives. Drawing on a cross-Canada survey of over one hundred organizations, we explore the reasons why communities undertake CBM, the monitoring protocols they follow, and the extent to which CBM program members feel their findings are incorporated into formal (i.e., government-led) decision-making processes. Our results indicate that despite following standardized and credible monitoring protocols, fewer than half of CBM organizations report that their data is being used to inform water policy at any level of government. Moreover, respondents report higher rates of cooperation and data-sharing between CBM organizations themselves than between CBM organizations and their respective governments. These findings are significant, because many governments continue to express support for CBM. We explore the barriers between CBM data collection and government policy, and suggest that structural barriers include lack of multi-year funding, inconsistent protocols, and poor communication. More broadly, we argue that the distinction between formal and informal programming is unclear, and that addressing known CBM challenges will rely on a change in perception: CBM cannot simply be a less expensive alternative to government-driven data collection. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. From microbes to water districts: Linking observations across scales to uncover the implications of riparian and channel management on water quality in an irrigated agricultural landscape

    Science.gov (United States)

    Webster, A.; Cadenasso, M. L.

    2016-12-01

    Interactions among runoff, riparian and stream ecosystems, and water quality remain uncertain in many settings, particularly those heavily impacted by human activities. For example, waterways in the irrigated agricultural landscape of California's Central Valley are seasonally disconnected from groundwater tables and are extensively modified by infrastructure and management. These conditions make the impact of riparian and channel management difficult to predict across scales, which hinders efforts to promote best management practices to improve water quality. We seek to link observations across catchment, reach, and patch scales to understand patterns of nitrate and turbidity in waterways draining irrigated cropland. Data was collected on 80 reaches spanning two water management districts. At the catchment scale, water districts implemented waterway and riparian management differently: one water district had a decentralized approach, allowing individual land owners to manage their waterway channels and banks, while the other had a centralized approach, in which land owners defer management to a district-run program. At the reach scale, riparian and waterway vegetation, geomorphic complexity, and flow conditions were quantified. Reach-scale management such as riparian planting projects and channel dredging frequency were also considered. At the patch scale, denitrification potential and organic matter were measured in riparian toe-slope soils and channel sediments, along with associated vegetation and geomorphic features. All factors were tested for their ability to predict water quality using generalized linear mixed effects models and the consistency of predictors within and across scales was evaluated. A hierarchy of predictors emerges: catchment-scale management regimes predict reach-scale geomorphic and vegetation complexity, which in turn predicts sediment denitrification potential - the patch-scale factor most associated with low nitrate. Similarly

  13. Design of medium band gap Ag-Bi-Nb-O and Ag-Bi-Ta-O semiconductors for driving direct water splitting with visible light.

    Science.gov (United States)

    Wang, Limin; Cao, Bingfei; Kang, Wei; Hybertsen, Mark; Maeda, Kazuhiko; Domen, Kazunari; Khalifah, Peter G

    2013-08-19

    Two new metal oxide semiconductors belonging to the Ag-Bi-M-O (M = Nb, Ta) chemical systems have been synthesized as candidate compounds for driving overall water splitting with visible light on the basis of cosubstitution of Ag and Bi on the A-site position of known Ca2M2O7 pyrochlores. The low-valence band edge energies of typical oxide semiconductors prevents direct water splitting in compounds with band gaps below 3.0 eV, a limitation which these compounds are designed to overcome through the incorporation of low-lying Ag 4d(10) and Bi 6s(2) states into compounds of nominal composition "AgBiM2O7". It was found that the "AgBiTa2O7" pyrochlores are in fact a solid solution with an approximate range of Ag(x)Bi(5/6)Ta2O(6.25+x/2) with 0.5 semiconductors with the onset of strong direct absorption at 2.72 and 2.96 eV, respectively. Electronic structure calculations for an ordered AgBiNb2O7 structure show that the band gap reduction and the elevation of the valence band primarily result from hybridized Ag d(10)-O 2p orbitals that lie at higher energy than the normal O 2p states in typical pyrochlore oxides. While the minimum energy gap is direct in the band structure, the lowest energy dipole allowed optical transitions start about 0.2 eV higher in energy than the minimum energy transition and involve different bands. This suggests that the minimum electronic band gap in these materials is slightly smaller than the onset energy for strong absorption in the optical measurements. The elevated valence band energies of the niobate and tantalate compounds are experimentally confirmed by the ability of these compounds to reduce 2 H(+) to H2 gas when illuminated after functionalization with a Pt cocatalyst.

  14. Linking hydrology of traditional irrigation canals and socio-economic aspects of agricultural water use around Mt. Kilimanjaro

    Science.gov (United States)

    Kimaro, Jerome; Scharsich, Valeska; Huwe, Bernd; Bogner, Christina

    2017-04-01

    Traditional irrigation network around Mt. Kilimanjaro has been an important resource for both ecosystem functioning and agricultural production. However, a number of irrigation furrows can no longer maintain their discharge throughout the year and their future sustainability is uncertain. The actual efforts to improve the water supply were unsuccessful. We attribute this failure to a lack of information about the actual causes and extent of the problem. We suppose that there is a strong link between the socio-economic aspects like institutional and community management of the furrows and conflicts about water use. Therefore, we conducted a study to determine the relationship between current hydrological patterns and socio-economic aspects of agricultural water use. We measured discharge at 11 locations along an altitudinal gradient on the southern slopes of Mt. Kilimanjaro. Additionally, we conducted focus group discussions with participants from 15 villages and key informants interviews (n = 15). We found that the mean discharge did not differ significantly between dry and rainy seasons (ANOVA, p = 0.17). The overall discharge pattern indicated that furrows located in lower altitude had higher mean monthly discharge rate of 65 l s-1 compared to 11.5 l s-1 at the source area of the canals. This is due to the convergence of canals downstream. 41% of furrows were seasonal, 22% dry and only 37% perennial. Despite of a seemingly better water resource availability downstream, water conflicts are a major challenge across the whole mountain communities. Key informants and group discussions reported poor management of water on the district level. The Rural Moshi and Hai District Councils operate on a top down approach that give less power to the local water management committees. However, the latter have been an important part of the traditional management system for decades. Since 1990, the district authorities are using 65% of springs from the catchment to abstract water

  15. Simulated nutrient dissolution of Asian aerosols in various atmospheric waters: Potential links to marine primary productivity

    Science.gov (United States)

    Wang, Lingyan; Bi, Yanfeng; Zhang, Guosen; Liu, Sumei; Zhang, Jing; Xu, Zhaomeng; Ren, Jingling; Zhang, Guiling

    2017-09-01

    To probe the bioavailability and environmental mobility of aerosol nutrient elements (N, P, Si) in atmospheric water (rainwater, cloud and fog droplets), ten total suspended particulate (TSP) samples were collected at Fulong Mountain, Qingdao from prevailing air mass trajectory sources during four seasons. Then, a high time-resolution leaching experiment with simulated non-acidic atmospheric water (non-AAW, Milli-Q water, pH 5.5) and subsequently acidic atmospheric water (AAW, hydrochloric acid solution, pH 2) was performed. We found that regardless of the season or source, a monotonous decreasing pattern was observed in the dissolution of N, P and Si compounds in aerosols reacted with non-AAW, and the accumulated dissolved curves of P and Si fit a first-order kinetic model. No additional NO3- + NO2- dissolved out, while a small amount of NH4+ in Asian dust (AD) samples was released in AAW. The similar dissolution behaviour of P and Si from non-AAW to AAW can be explained by the Transition State Theory. The sources of aerosols related to various minerals were the natural reasons that affected the amounts of bioavailable phosphorus and silicon in aerosols (i.e., solubility), which can be explained by the dissolution rate constant of P and Si in non-AAW with lower values in mineral aerosols. The acid/particle ratio and particle/liquid ratio also have a large effect on the solubility of P and Si, which was implied by Pearson correlation analysis. Acid processing of aerosols may have great significance for marine areas with limited P and Si and post-acidification release increases of 1.1-10-fold for phosphorus and 1.2-29-fold for silicon. The decreasing mole ratio of P and Si in AAW indicates the possibility of shifting from a Si-limit to a P-limit in aerosols in the ocean, which promotes the growth of diatoms prior to other algal species.

  16. Genetic and biochemical analysis reveals linked QTLs determining natural variation for fruit post-harvest water loss in pepper (Capsicum).

    Science.gov (United States)

    Popovsky-Sarid, Sigal; Borovsky, Yelena; Faigenboim, Adi; Parsons, Eugene P; Lohrey, Gregory T; Alkalai-Tuvia, Sharon; Fallik, Elazar; Jenks, Matthew A; Paran, Ilan

    2017-02-01

    Molecular markers linked to QTLs controlling post-harvest fruit water loss in pepper may be utilized to accelerate breeding for improved shelf life and inhibit over-ripening before harvest. Bell pepper (Capsicum annuum L.) is an important vegetable crop world-wide. However, marketing is limited by the relatively short shelf life of the fruit due to water loss and decay that occur during prolonged storage. Towards breeding pepper with reduced fruit post-harvest water loss (PWL), we studied the genetic, physiological and biochemical basis for natural variation of PWL. We performed quantitative trait locus (QTL) mapping of fruit PWL in multiple generations of an interspecific cross of pepper, which resulted in the identification of two linked QTLs on chromosome 10 that control the trait. We further developed near-isogenic lines (NILs) for characterization of the QTL effects. Transcriptome analysis of the NILs allowed the identification of candidate genes associated with fruit PWL-associated traits such as cuticle biosynthesis, cell wall metabolism and fruit ripening. Significant differences in PWL between the NILs in the immature fruit stage, differentially expressed cuticle-associated genes and differences in the content of specific chemical constituents of the fruit cuticle, indicated a likely influence of cuticle composition on the trait. Reduced PWL in the NILs was associated with delayed over-ripening before harvest, low total soluble solids before storage, and reduced fruit softening after storage. Our study enabled a better understanding of the genetic and biological processes controlling natural variation in fruit PWL in pepper. Furthermore, the genetic materials and molecular markers developed in this study may be utilized to breed peppers with improved shelf life and inhibited over-ripening before harvest.

  17. A Comparative Analysis of Yield Gaps and Water Productivity on Smallholder Farms in Ethiopia, South Africa and Tunisia

    NARCIS (Netherlands)

    Jovanovic, Nebo; Musvoto, Constansia; Clercq, De Willem; Pienaar, Cou; Petja, Brilliant; Zairi, Abdelaziz; Hanafi, Salia; Ajmi, Tarek; Mailhol, Jean Claude; Cheviron, Bruno; Albasha, Rami; Habtu, Solomon; Yazew, Eyasu; Kifle, Muluberhan; Fissahaye, Degol; Aregay, Gebremeskel; Habtegebreal, Kiros; Gebrekiros, Abreha; Woldu, Yirga; Froebrich, Jochen

    2018-01-01

    Agriculture in developing countries will have to transform and increase production by an estimated 70% in order to meet demands by 2050. Although well-managed commercial farms offer little manoeuvring space for increasing agricultural water productivity, smallholder farms usually operate at low

  18. Linking R&D Activities with Teaching: Water Quality Monitoring in Aquaculture as a Remote Laboratory Proxy for Environmental Studies

    Directory of Open Access Journals (Sweden)

    Maria Teresa Borges

    2011-04-01

    Full Text Available This work presents a system for on-line study purposes and for demonstrative operation of water quality monitoring based on previous full-scale trials in a commercial aquaculture facility under the scope of a R&D project. This system is still under development, and was designed for sharing resources in R&D activities and later in distance learning blended courses. An application developed in LabVIEW is responsible for receiving information from physical and chemical data (water level, flow, oxygen, temperature, pH, ORP and CO2 through a hardware interface. The acquired data are recorded in a Microsoft Access database that can be locally queried as desired. An IP camera allows students to observe the system in real-time. Students can log into the system and follow the real-time variations of a specific water quality parameter and the synergetic effects of these changes on the levels of other constituents. The water tanks contain no living beings in order to allow free adjustments of the parameters under study. The system description, data and remote access link is integrated in a basic course available in a Moodle® server. The goal of this course is to provide a stimulating interdisciplinary environment to a diverse group of undergraduate students, where critical research questions related to water are addressed. This system, unique in the area concerning with our knowledge, intends to contribute also to students’ training on data monitoring and analysis; and to nourish analytical skills and creativity of future scientists by encouraging potential graduate students to go further. Finally, this system allows the students to be familiar with the use of some new information technologies.

  19. Linking hydraulic properties of fire-affected soils to infiltration and water repellency

    Science.gov (United States)

    Moody, John A.; Kinner, David A.; Úbeda, Xavier

    2009-12-01

    SummaryHeat from wildfires can produce a two-layer system composed of extremely dry soil covered by a layer of ash, which when subjected to rainfall, may produce extreme floods. To understand the soil physics controlling runoff for these initial conditions, we used a small, portable disk infiltrometer to measure two hydraulic properties: (1) near-saturated hydraulic conductivity, K f and (2) sorptivity, S( θ i), as a function of initial soil moisture content, θ i, ranging from extremely dry conditions ( θ i ash, reference soils, soils unaffected by fire, and fire-affected soils. Each has a different degrees of water repellency that influences K f and S( θ i). Values of K f ranged from 4.5 × 10 -3 to 53 × 10 -3 cm s -1 for ash; from 0.93 × 10 -3 to 130 × 10 -3 cm s -1 for reference soils; and from 0.86 × 10 -3 to 3.0 × 10 -3 cm s -1, for soil unaffected by fire, which had the lowest values of K f. Measurements indicated that S( θ i) could be represented by an empirical non-linear function of θ i with a sorptivity maximum of 0.18-0.20 cm s -0.5, between 0.03 and 0.08 cm 3 cm -3. This functional form differs from the monotonically decreasing non-linear functions often used to represent S( θ i) for rainfall-runoff modeling. The sorptivity maximum may represent the combined effects of gravity, capillarity, and adsorption in a transitional domain corresponding to extremely dry soil, and moreover, it may explain the observed non-linear behavior, and the critical soil-moisture threshold of water repellent soils. Laboratory measurements of K f and S( θ i) are the first for ash and fire-affected soil, but additional measurements are needed of these hydraulic properties for in situ fire-affected soils. They provide insight into water repellency behavior and infiltration under extremely dry conditions. Most importantly, they indicate how existing rainfall-runoff models can be modified to accommodate a possible two-layer system in extremely dry conditions. These

  20. Surface effects on phase distributions of a fast-quenched miscibility gap type system - Succinonitrile-water

    Science.gov (United States)

    Frazier, D. O.; Facemire, B. R.; Fanning, U. S.

    1986-01-01

    If a binary homogeneous melt is cooled into an immiscible region, the newly formed second phase will generally have a density different from the parent phase, and will separate readily by sedimentation. Observation of solidification processes in microgravity indicates that outside of sedimentation, at least two other important effets can separate the phases: (1) preferential wetting, and (2) thermal migration of second-phase droplets due to interfacial tension gradients. The latter effect would drive the minority phase along the thermal gradient toward the hottest part (assuming the interfacial tension decreases with increasing temperature), which is usually away from the crucible wall. On the other hand, if the minority phase preferentially wets the crucible, a minority phase layer which thickens as initial solution compositions approach critical, will form adjacent to the solid surface and remain in the coldest region of the ingot. This study presents compelling preliminary evidence that these two effects do exist and that they compete with one another. However, the temperature dependence of preferential wetting below T(c) for the current system of study is, as yet, undetermined. These effects are sensitive to the initial concentration of a hypermonotectic solution cooling through a miscibility gap.

  1. Urban Stormwater Quality: Linking Pesticide Variability To Our Sustainable Water Future

    Science.gov (United States)

    Rippy, M.; Deletic, A.; Gernjak, W.

    2015-12-01

    Climate change and global population growth demand creative, multidisciplinary, and multi-benefit approaches for sustaining adequate fresh water resources and protecting ecosystem health. Currently, a driving factor of aquatic ecosystem degradation (stormwater) is also one of the largest untapped urban freshwater resources. This suggests that ecosystem protection and potable water security might both be achieved via treating and capturing stormwater for human use (e.g., potable substitution). The viability of such a scheme, however, depends on 1) initial stormwater quality (e.g., the contaminants present and their associated human/environmental health risks), 2) the spatial and temporal variability of contaminants in stormwater, and 3) the capacity of existing technologies to treat those contaminants to fit for purpose standards. Here we present results from a four year study of urban stormwater conducted across ten catchments and four states in Australia that addresses these three issues relative to stormwater pesticides. In total, 19 pesticides were detected across all sites and times. In general, pesticide concentrations were lower than has been reported in other countries, including the United States, Canada and Europe. This is reflected in few exceedences of public health (< 1%) and aquatic ecosystem standards (0% for invertebrates and fish, < 1% for algae and plants). Interestingly, pesticide patterns were found to be stable across seasons, and years, but varied across catchments. These catchment-specific fingerprints may reflect preferential commercial product use, as they map closely to co-occurrence patterns in registered Australian products. Importantly, the presence of catchment-specific pesticide variability has clear management implications; namely, urban stormwater must be managed at the catchment level and target local contaminant suites in order to best achieve desired human use and environmental protection standards.

  2. Reactivity of the Bacteria-Water Interface: Linking Nutrient Availability to Bacteria-Metal Interactions

    Science.gov (United States)

    Fowle, D. A.; Daughney, C. J.; Riley, J. L.

    2002-12-01

    Identifying and quantifying the controls on metal mobilities in geologic systems is critical in order to understand processes such as global element cycling, metal transport in near-surface water-rock systems, sedimentary diagenesis, and mineral formation. Bacteria are ubiquitous in near-surface water-rock systems, and numerous laboratory and field studies have demonstrated that bacteria can facilitate the formation and dissolution of minerals, and enhance or inhibit contaminant transport. However, despite the growing evidence that bacteria play a key role in many geologic processes in low temperature systems, our understanding of the influence of the local nutrient dynamics of the system of interest on bacteria-metal interactions is limited. Here we present data demonstrating the effectiveness of coupling laboratory experiments with geochemical modeling to isolate the effect of nutrient availability on bacterially mediated proton and metal adsorption reactions. Experimental studies of metal-bacteria interactions were conducted in batch reactors as a function of pH, and solid-solute interactions after growth in a variety of defined and undefined media. Media nutrient composition (C,N,P) was quantified before and after harvesting the cells. Surface complexation models (SCM) for the adsorption reactions were developed by combining sorption data with the results of acid-base titrations, and in some cases zeta potential titrations of the bacterial surface. Our results indicate a clear change in both buffering potential and metal binding capacity of the cell walls of Bacillus subtilis as a function of initial media conditions. Combining current studies with our past studies on the effects of growth phase and others work on temperature dependence on metal adsorption we hope to develop a holistic surface complexation model for quantifying bacterial effects on metal mass transfer in many geologic systems.

  3. Biomass Assessment. Assessment of global biomass potentials and their links to food, water, biodiversity, energy demand and economy. Inventory and analysis of existing studies. Supporting document

    International Nuclear Information System (INIS)

    Dornburg, V.; Faaij, A.; Verweij, P.; Banse, M.; Van Diepen, K.; Van Keulen, H.; Langeveld, H.; Meeusen, M.; Van de Ven, G.; Wester, F.; Alkemade, R.; Ten Brink, B.; Van den Born, G.J.; Van Oorschot, M.; Ros, J.; Smout, F.; Van Vuuren, D.; Van den Wijngaart, R.; Aiking, H.; Londo, M.; Mozaffarian, H.; Smekens, K.; Lysen, E.

    2008-01-01

    This supporting document contains the result from the inventory phase of the biomass assessment of global biomass potentials and their links to food, water, biodiversity, energy demand and economy. This study provides a comprehensive assessment of global biomass potential estimates, focusing on the various factors affecting these potentials, such as food supplies, water use, biodiversity, energy demands and agro-economics

  4. Projecting water yield and ecosystem productivity across the United States by linking an ecohydrological model to WRF dynamically downscaled climate data

    Science.gov (United States)

    Shanlei Sun; Ge Sun; Erika Cohen Mack; Steve McNulty; Peter V. Caldwell; Kai Duan; Yang Zhang

    2016-01-01

    Quantifying the potential impacts of climatechange on water yield and ecosystem productivity is essential to developing sound watershed restoration plans, andecosystem adaptation and mitigation strategies. This study links an ecohydrological model (Water Supply and StressIndex, WaSSI) with WRF (Weather Research and Forecasting Model) using dynamically downscaled...

  5. Linking air and water transport in intact soils to macropore characteristics inferred from X-ray computed tomography

    DEFF Research Database (Denmark)

    Katuwal, S.; Nørgaard, Trine; Møldrup, Per

    2015-01-01

    Soil macropores often control fluid flow and solute transport, and quantification of macropore characteristics including their variability in space and time are essential to predict soil hydraulic and hydrogeochemical functions. In this study, measurements of air and solute transport properties...... and direct macropore visualization by X-ray CT scanning were carried out on 17 large (19-cm diam.; 20-cm length) undisturbed soil columns sampled across a field site (Silstrup, Denmark) with natural gradients in texture and density. Air permeability (ka) at in-situ water content and -20 hPa of matric......-porosity, suggesting that density is the main control of functional soil structure and gas and solute transport at the Silstrup site. Linking gas transport and chemical tracer experiments with X-ray CT based visualization and quantification of macro-porosity was found to be a powerful method to understand field scale...

  6. Knowledge Gaps

    DEFF Research Database (Denmark)

    Lyles, Marjorie; Pedersen, Torben; Petersen, Bent

    2003-01-01

    The study explores what factors influence the reduction of managers' perceivedknowledge gaps in the context of the environments of foreign markets. Potentialdeterminants are derived from traditional internationalization theory as well asorganizational learning theory, including the concept...... of absorptive capacity. Building onthese literature streams a conceptual model is developed and tested on a set of primarydata of Danish firms and their foreign market operations. The empirical study suggeststhat the factors that pertain to the absorptive capacity concept - capabilities ofrecognizing......, assimilating, and utilizing knowledge - are crucial determinants ofknowledge gap elimination. In contrast, the two factors deemed essential in traditionalinternationalization process theory - elapsed time of operations and experientiallearning - are found to have no or limited effect.Key words...

  7. Modeling stomatal conductance in the earth system: linking leaf water-use efficiency and water transport along the soil-plant-atmosphere continuum

    Science.gov (United States)

    Bonan, G. B.; Williams, M.; Fisher, R. A.; Oleson, K. W.

    2014-09-01

    The Ball-Berry stomatal conductance model is commonly used in earth system models to simulate biotic regulation of evapotranspiration. However, the dependence of stomatal conductance (gs) on vapor pressure deficit (Ds) and soil moisture must be empirically parameterized. We evaluated the Ball-Berry model used in the Community Land Model version 4.5 (CLM4.5) and an alternative stomatal conductance model that links leaf gas exchange, plant hydraulic constraints, and the soil-plant-atmosphere continuum (SPA). The SPA model simulates stomatal conductance numerically by (1) optimizing photosynthetic carbon gain per unit water loss while (2) constraining stomatal opening to prevent leaf water potential from dropping below a critical minimum. We evaluated two optimization algorithms: intrinsic water-use efficiency (ΔAn /Δgs, the marginal carbon gain of stomatal opening) and water-use efficiency (ΔAn /ΔEl, the marginal carbon gain of transpiration water loss). We implemented the stomatal models in a multi-layer plant canopy model to resolve profiles of gas exchange, leaf water potential, and plant hydraulics within the canopy, and evaluated the simulations using leaf analyses, eddy covariance fluxes at six forest sites, and parameter sensitivity analyses. The primary differences among stomatal models relate to soil moisture stress and vapor pressure deficit responses. Without soil moisture stress, the performance of the SPA stomatal model was comparable to or slightly better than the CLM Ball-Berry model in flux tower simulations, but was significantly better than the CLM Ball-Berry model when there was soil moisture stress. Functional dependence of gs on soil moisture emerged from water flow along the soil-to-leaf pathway rather than being imposed a priori, as in the CLM Ball-Berry model. Similar functional dependence of gs on Ds emerged from the ΔAn/ΔEl optimization, but not the ΔAn /gs optimization. Two parameters (stomatal efficiency and root hydraulic

  8. Data report of tight-lattice rod bundle thermal-hydraulic tests (2). Gap-width effect test using 37-rod bundle simulated water-cooled breeder reactor (Contract research)

    International Nuclear Information System (INIS)

    Tamai, Hidesada; Kureta, Masatoshi; Liu, Wei; Akimoto, Hajime; Sato, Takashi; Watanabe, Hironori; Ohnuki, Akira

    2006-11-01

    Japan Atomic Energy Agency has been performing tight-lattice rod bundle thermal-hydraulic tests to realize essential technologies for the technological and engineering feasibility of super high burn-up water-cooled breeder reactor featured by a high breeding ratio and super high burn-up by reducing the core water volume in water-cooled reactor. The tests are performing to make clear the fundamental subjects related to the boiling transition (BT) (Subjects: BT criteria under a highly tight-lattice rod bundle, effects of gap-width between rods and of rod-bowing) using 37-rod bundles (Base case test section (1.3mm gap-width), Two parameter effect test sections (Gap-width effect one (1.0mm) and Rod-bowing one)). In the present report, we summarize the test results from the gap-width effect test section. The thermal-hydraulic characteristics were obtained for the critical power under the steady-state and transient conditions, the pressure drop and the wall heat transfer within a wide range of pressure, flow rate, etc. including normal operational conditions of the designed reactor. Then the gap-width effects were also obtained from the comparison between the results using the base case test section and the gap-width effect one. (author)

  9. Surface-water quantity and quality, aquatic biology, stream geomorphology, and groundwater-flow simulation for National Guard Training Center at Fort Indiantown Gap, Pennsylvania, 2002-05

    Science.gov (United States)

    Langland, Michael J.; Cinotto, Peter J.; Chichester, Douglas C.; Bilger, Michael D.; Brightbill, Robin A.

    2010-01-01

    Base-line and long-term monitoring of water resources of the National Guard Training Center at Fort Indiantown Gap in south-central Pennsylvania began in 2002. Results of continuous monitoring of streamflow and turbidity and monthly and stormflow water-quality samples from two continuous-record long-term stream sites, periodic collection of water-quality samples from five miscellaneous stream sites, and annual collection of biological data from 2002 to 2005 at 27 sites are discussed. In addition, results from a stream-geomorphic analysis and classification and a regional groundwater-flow model are included. Streamflow at the facility was above normal for the 2003 through 2005 water years and extremely high-flow events occurred in 2003 and in 2004. Water-quality samples were analyzed for nutrients, sediments, metals, major ions, pesticides, volatile and semi-volatile organic compounds, and explosives. Results indicated no exceedances for any constituent (except iron) above the primary and secondary drinking-water standards or health-advisory levels set by the U.S. Environmental Protection Agency. Iron concentrations were naturally elevated in the groundwater within the watershed because of bedrock lithology. The majority of the constituents were at or below the method detection limit. Sediment loads were dominated by precipitation due to the remnants of Hurricane Ivan in September 2004. More than 60 percent of the sediment load measured during the entire study was transported past the streamgage in just 2 days during that event. Habitat and aquatic-invertebrate data were collected in the summers of 2002-05, and fish data were collected in 2004. Although 2002 was a drought year, 2003-05 were above-normal flow years. Results indicated a wide diversity in invertebrates, good numbers of taxa (distinct organisms), and on the basis of a combination of metrics, the majority of the 27 sites indicated no or slight impairment. Fish-metric data from 25 sites indicated results

  10. Water data to answer urgent water policy questions: Monitoring design, available data and filling data gaps for determining the effectiveness of agricultural management practices for reducing tributary nutrient loads to Lake Erie

    Science.gov (United States)

    Bentanzo, Elin A.; Choquette, Anne F.; Reckhow, Kenneth H.; Hayes, Laura; Hagan, Erik R; Argue, Denise M.; Cangelosi, A.A.

    2015-01-01

    Throughout its history, the United States has made major investments in assessing natural resources, such as soils, timber, oil and gas, and water. These investments allow policy makers, the private sector and the American public to make informed decisions about cultivating, harvesting or conserving these resources to maximize their value for public welfare, environmental conservation and the economy. As policy issues evolve, new priorities and challenges arise for natural resource assessment, and new approaches to monitoring are needed. For example, informed conservation and use of the nation’s finite fresh water resources in the context of increasingly intensive land development is a priority for today’s policy decisionmakers. There is a need to evaluate whether today’s water monitoring programs are generating the information needed to answer questions surrounding these new policy priorities. The Northeast-Midwest Institute (NEMWI), in cooperation with the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program, initiated this project to explore the types and amounts of water data needed to address water-quality related policy questions of critical concern to today’s policy makers. The collaborating entities identified two urgent water policy questions and conducted case studies in the Northeast-Midwest region to determine the water data needed, water data available, and the best ways to fill the data gaps relative to those questions. This report details the output from one case study and focuses on the Lake Erie drainage basin, a data-rich area expected to be a best-case scenario in terms of water data availability.

  11. Membrane-Based Separation of Phenol/Water Mixtures Using Ionically and Covalently Cross-Linked Ethylene-Methacrylic Acid Copolymers

    Directory of Open Access Journals (Sweden)

    Alexander Mixa

    2008-01-01

    Full Text Available Membrane-based separation of phenol/water mixtures with concentrations of phenol between 3 wt% and 8 wt% in the feed has been performed with nonmodified as well as cross-linked ethylene-methacrylic acid (E-MAA copolymers with different amounts of methacrylic acid. As cross-linking agents, aluminium acetyl acetonate, which leads to ionically cross-linked membranes, and 2,3,5,6-tetramethyl-1,4-phenylene diamine and glycerine digycidether, leading to covalently cross-linked membranes, have been used. Generally, it was found that with increasing phenol content in the feed, the total flux is increasing whereas the enrichment factor is decreasing. Using nonmodified membranes with higher methacrylic acid monomer content in the polymer, lower fluxes and higher enrichment factors were observed. Investigation of different cross-linked membranes showed that with high phenol concentration in the feed, ionic cross-linking seems to be very promising. Furthermore, variation of feed temperature shows that ionically cross-linked membranes reached higher fluxes as well as higher enrichment factors at elevated temperatures. The temperature-dependent data were fitted based on an Arrhenius-type equation, and activation energies for the permeation of phenol and water through the membrane were calculated.

  12. Dehydration of an azeotrope of ethanol/water by sodium carboxymethylcellulose membranes cross-linked with organic or inorganic cross-linker

    Directory of Open Access Journals (Sweden)

    2010-11-01

    Full Text Available To control the swelling of sodium carboxymethylcellulose (CMCNa membranes, mixtures of CMCNa and glutaraldehyde (GA and mixtures of CMCNa as an organic component and tetraethoxysilane (TEOS as an inorganic component were prepared, and CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes were formed. In the separation of an ethanol/water azeotrope by pervaporation (PV, the effects of the GA or TEOS content on the water/ethanol selectivity and permeability of these CMCNa/GA cross-linked and CMCNa/TEOS hybrid membranes were investigated. Cross-linked and hybrid membranes containing up to 10 wt% GA or 10 wt% TEOS exhibited higher water/ethanol selectivity than CMCNa membrane without any cross-linker. This resulted from both increased density and depressed swelling of the membranes by the formation of a cross-linked structure. The relationship between the structure of the CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes and their permeation and separation characteristics for an ethanol/water azeotrope during PV is discussed in detail.

  13. Minding the Gap

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, Millicent Anne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-23

    Neutron & X-ray scattering provides nano- to meso-scale details of complex fluid structure; 1D electronic density maps dervied from SAXS yield molecular level insights; Neutron reflectivity provides substructure details of substrate supported complex fluids; Complex fluids composition can be optimized to support a wide variety of both soluble and membrane proteins; The water gap dimensions can be finely tuned through polymer component.

  14. Differential growth responses to water balance of coexisting deciduous tree species are linked to wood density in a Bolivian tropical dry forest.

    Science.gov (United States)

    Mendivelso, Hooz A; Camarero, J Julio; Royo Obregón, Oriol; Gutiérrez, Emilia; Toledo, Marisol

    2013-01-01

    A seasonal period of water deficit characterizes tropical dry forests (TDFs). There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability.

  15. Differential growth responses to water balance of coexisting deciduous tree species are linked to wood density in a Bolivian tropical dry forest.

    Directory of Open Access Journals (Sweden)

    Hooz A Mendivelso

    Full Text Available A seasonal period of water deficit characterizes tropical dry forests (TDFs. There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability.

  16. Differential Growth Responses to Water Balance of Coexisting Deciduous Tree Species Are Linked to Wood Density in a Bolivian Tropical Dry Forest

    Science.gov (United States)

    Mendivelso, Hooz A.; Camarero, J. Julio; Royo Obregón, Oriol; Gutiérrez, Emilia; Toledo, Marisol

    2013-01-01

    A seasonal period of water deficit characterizes tropical dry forests (TDFs). There, sympatric tree species exhibit a diversity of growth rates, functional traits, and responses to drought, suggesting that each species may possess different strategies to grow under different conditions of water availability. The evaluation of the long-term growth responses to changes in the soil water balance should provide an understanding of how and when coexisting tree species respond to water deficit in TDFs. Furthermore, such differential growth responses may be linked to functional traits related to water storage and conductance. We used dendrochronology and climate data to retrospectively assess how the radial growth of seven coexisting deciduous tree species responded to the seasonal soil water balance in a Bolivian TDF. Linear mixed-effects models were used to quantify the relationships between basal area increment and seasonal water balance. We related these relationships with wood density and sapwood production to assess if they affect the growth responses to climate. The growth of all species responded positively to water balance during the wet season, but such responses differed among species as a function of their wood density. For instance, species with a strong growth response to water availability averaged a low wood density which may facilitate the storage of water in the stem. By contrast, species with very dense wood were those whose growth was less sensitive to water availability. Coexisting tree species thus show differential growth responses to changes in soil water balance during the wet season. Our findings also provide a link between wood density, a trait related to the ability of trees to store water in the stem, and wood formation in response to water availability. PMID:24116001

  17. Analysis of drought and desertification by means of aridity indices and the estimation of water gap in Baja California Sur, Northwest Mexico

    Directory of Open Access Journals (Sweden)

    Enrique Troyo Diéguez

    2013-10-01

    Full Text Available In Baja California Sur (BCS, Mexico, dry-semi warm and warm climates prevail associated to an extreme trend of diurnal temperatures and the environmental dryness. In this State, the maximum summer t exceeds 40° C and the minimum varies from 5 to 12° C, with a minimal for the State of 2° C in winter, at the top of the Sierra de La Laguna; only Los Cabos region has a warm humid climate. Because precipitation in the state is low, oscillating from 310 mm in the southern area of the state to 120 mm per year in the northern portion, predictions and scenarios under climate conditions point to an intensification of droughts. The aim of this work was to carry out a comparative analysis of trends of temperature, precipitation and hydro-environmental aridity among contrasting localities of BCS, by means of the application of Aridity Indexes and the determination of the Standardized Water Gap (BHE, through a numerical scale modification of the De Martonne Index. With the values of temperature and precipitation for the different climate change scenarios for four weather stations, the indicators Hydro Environmental Availability Index (IDHA and Hydro Environmental Drought Index (ISHA were calculated to determine their trend and the consequent BHE, an innovative quantification of wáter deficit, which is proposed in this paper. The máximum value of BHE (10 units, indicating prevalence of drought, is observed from February to June in almost the entire state.

  18. Experimental and Theoretical Study of Dryout and Post-Dryout Heat Transfer of Steam-Water Two-Phase Flow in the Annular Channel with Narrow Gap

    International Nuclear Information System (INIS)

    Aye Myint

    2004-10-01

    Two-phase annular flow with heat transfer is prevalent in many processes such as industrial and energy reformation processes. Recently, advances in high performance electronic chips and the miniaturisation of electronic circuits in which high heat flux will be created and other compact systems such as Integrated Nuclear Power Device (INPD), the refrigeration/air conditioning, automobile environment control systems have resulted in a great demand for developing efficient heat transfer techniques to accommodate these high heat fluxes. It has been studied by many researchers because of its successful application in many areas, but its influence factor and mechanism of heat transfer remain somewhat unknown yet. In order to understand the heat transfer and flow mechanism in the narrow annular channel, experimental and theoretical study of dryout and post-dryout heat transfer of steam-water two-phase flow in annular channel with narrow gap (1.0 mm and 1.5 mm) have been carried out. The working fluid is deionized water. The range of experimental pressure is 1.0 ∼ 6.OMPa. In correspondence with two different narrow gaps, two kinds of test sections were designed. The test sections were made of specially processed straight stainless steel tubes with linearity error less than 0.01% to form narrow concentric annuli. It also needs a good sealed performance at high pressure and high temperature. The experiments were carried out to investigate the characteristics and occurring conditions of the dryout point. The former Soviet researcher Kutateladse's correlation, based on round tube, was quoted and modified to apply barrow annuli under low flow conditions. At full conditions of the influencing factors, such as geometry of test section, pressure, mass flux, heat flux etc., an empirical correlation was developed to apply to bilaterally heated annuli and it had a good agreement with the experimental data A new analytical model for the dryout point of critical quality in

  19. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers

    DEFF Research Database (Denmark)

    Kirkeskov, Lilli; Kristiansen, Eva; Bøggild, Henrik

    2010-01-01

    Kirkeskov L, Kristiansen E, Bøggild H, von Platen-Hallermund F, Sckerl H, Carlsen A, Larsen MJ, Poulsen S. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers. Community...... Dent Oral Epidemiol 2010. (c) 2010 John Wiley & Sons A/S Abstract - Objectives: To study the association between fluoride concentration in drinking water and dental caries in Danish children. Methods: The study linked registry data on fluoride concentration in drinking water over a 10-year period...... with data on dental caries from the Danish National Board of Health database on child dental health for 5-year-old children born in 1989 and 1999, and for 15-year-old children born in 1979 and 1989. The number of children included in the cohorts varied between 41.000 and 48.000. Logistic regression was used...

  20. The Missing Link: the Role of Floodplain Tie Channels in Connecting Off River Water Bodies to Lowland Rivers

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.; Day, G.

    2005-05-01

    Along lowland river systems across the globe the exchange of water, sediment, carbon, nutrients and biota between main stem rivers and off-river water bodies (ORWB) is facilitated by the presence of stable secondary channels referred to here as tie channels. Sixty five percent of the ORWB along the middle Fly River in Papua New Guinea connect to the river through such channels. A similar percentage of the 37 ORWB located between Baton Rouge and Memphis on the lower Mississippi River at one time were linked to the river by tie or batture (as they are locally known) channels. Levee construction and other alterations aimed at flood control or navigation on the Mississippi have left only a handful of lakes connected to the river, of these, most are heavily altered by dredging or other modifications. Tie channels were also once common along major tributaries to the Mississippi, such as the Red River. In the much less disturbed Alaskan environment, tie channels are still common, especially along Birch Creek and the Koyukuk and Black rivers. Our studies on the Mississippi River, in Alaska and in Papua New Guinea indicate that tie channels possess a common channel form that is stable and self-maintaining for hundreds to possibly a thousand years. Tie channels exhibit narrow width to depth ratios (~ 5.5) and consistently scale in cross-sectional dimensions to the size of the lake into which they flow. Variations in river and lake stage drive flow bi-directionally through tie channels. A local high or sill in the bed of tie channels controls the degree and duration of connection between the river and ORWB, with many lakes becoming isolated during periods of low stage. The life-span of a tie channel depends on the rate of sediment loading to the ORWB. Our research indicates that this rate directly corresponds to the sediment loading in the main stem river. Along the Fly River, for example, a 5 to 7 fold increase in the river sediment load has resulted increases of 6 to 17

  1. Ultraviolet-B radiation induced cross-linking improves physical properties of cold- and warm-water fish gelatin gels and films.

    Science.gov (United States)

    Otoni, Caio G; Avena-Bustillos, Roberto J; Chiou, Bor-Sen; Bilbao-Sainz, Cristina; Bechtel, Peter J; McHugh, Tara H

    2012-09-01

    Cold- and warm-water fish gelatin granules were exposed to ultraviolet-B radiation for doses up to 29.7 J/cm(2). Solutions and films were prepared from the granules. Gel electrophoresis and refractive index were used to examine changes in molecular weight of the samples. Also, the gel strength and rheological properties of the solutions as well as the tensile and water vapor barrier properties of the films were characterized. SDS-PAGE and refractive index results indicated cross-linking of gelatin chains after exposure to radiation. Interestingly, UV-B treated samples displayed higher gel strengths, with cold- and warm-water fish gelatin having gel strength increases from 1.39 to 2.11 N and from 7.15 to 8.34 N, respectively. In addition, both gelatin samples exhibited an increase in viscosity for higher UV doses. For gelatin films, the cold-water fish gelatin samples made from irradiated granules showed greater tensile strength. In comparison, the warm-water gelatin films made from irradiated granules had lower tensile strength, but better water vapor barrier properties. This might be due to the UV induced cross-linking in warm-water gelatin that disrupted helical structures. Journal of Food Science copy; 2012 Institute of Food Technologists® No claim to original US government works.

  2. Linking fish tolerance to water quality criteria for the assessment of environmental flows: A practical method for streamflow regulation and pollution control.

    Science.gov (United States)

    Zhao, Changsen; Yang, Shengtian; Liu, Junguo; Liu, Changming; Hao, Fanghua; Wang, Zhonggen; Zhang, Huitong; Song, Jinxi; Mitrovic, Simon M; Lim, Richard P

    2018-05-15

    The survival of aquatic biota in stream ecosystems depends on both water quantity and quality, and is particularly susceptible to degraded water quality in regulated rivers. Maintenance of environmental flows (e-flows) for aquatic biota with optimum water quantity and quality is essential for sustainable ecosystem services, especially in developing regions with insufficient stream monitoring of hydrology, water quality and aquatic biota. Few e-flow methods are available that closely link aquatic biota tolerances to pollutant concentrations in a simple and practical manner. In this paper a new method was proposed to assess e-flows that aimed to satisfy the requirements of aquatic biota for both the quantity and quality of the streamflow by linking fish tolerances to water quality criteria, or the allowable concentration of pollutants. For better operation of water projects and control of pollutants discharged into streams, this paper presented two coefficients for streamflow adjustment and pollutant control. Assessment of e-flows in the Wei River, the largest tributary of the Yellow River, shows that streamflow in dry seasons failed to meet e-flow requirements. Pollutant influx exerted a large pressure on the aquatic ecosystem, with pollutant concentrations much higher than that of the fish tolerance thresholds. We found that both flow velocity and water temperature exerted great influences on the pollutant degradation rate. Flow velocity had a much greater influence on pollutant degradation than did the standard deviation of flow velocity. This study provides new methods to closely link the tolerance of aquatic biota to water quality criteria for e-flow assessment. The recommended coefficients for streamflow adjustment and pollutant control, to dynamically regulate streamflow and control pollutant discharge, are helpful for river management and ecosystems rehabilitation. The relatively low data requirement also makes the method easy to use efficiently in developing

  3. Going against the flow: A critical analysis of virtual water trade in the context of India's National River Linking Programme

    NARCIS (Netherlands)

    Verma, Shilp; Kampman, Doeke A.; van der Zaag, Pieter; Hoekstra, Arjen Ysbert

    2008-01-01

    Virtual water trade has been promoted as a tool to address national and regional water scarcity. In the context of international (food) trade, this concept has been applied with a view to optimize the flow of commodities considering the water endowments of nations. The concept states that water-rich

  4. Soil ciliate bioassay for the pore water habitat. A missing link between microflora and earthworm testing in soil toxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Berthold, A. [Lab. for Ecotoxicology, Univ. of Veterinary Medicine, Vienna (Austria); Jakl, T. [Chemicals Policy Unit, Federal Ministry of Agriculture, Forestry, Environment and Water Management, Vienna (Austria)

    2002-07-01

    Background, Scope and Goal. The chemical, pesticide and biocide legislation of the European Union assembles a variety of bioassays. Among the ecotoxicological tests involved, the testing strategy for the aquatic compartment builds up on three tests reflecting the main trophic levels (algae, Daphnia, fish). For the soil compartment at least one trophic level for a basic food chain is missing, namely between microflora and earthworms. Protozoa are an ideal missing link as they were shown to be the most prominent faunal contributors to nutrient cycling in soil ecosystems and as they represent the lacking first level consumers as well as the highly diverse microfauna. As protozoa inhabit the soil pore water, they can serve as direct indicators for the solved and thus bioavailable portion of xenobiotics. In order to widen the spectrum of available toxicity tests for a meaningful effect assessment for the soil compartment, a test with the soil ciliate Colpoda inflata (Ciliophora, Protozoa), introduced by Pratt et al. (1997), was improved. Methods. The novel improvements comprise a substantially refined inoculation and counting procedure, as well as the adaptation to yeast as a nutritional source. The test was designed to be rapid and easy to perform, in order to have both a higher degree of standardisation and reproducibility, as well as to be in compliance with international test guidelines. Results and Discussion. Five test substances, cadmium chloride, potassium dichromate, acetone, atrazine, and metolachlor, were used in single-compound, static, short-term exposure (24 h, 48 h) tests to examine the effect on the population growth of C. inflata. The median effective concentrations (EC50) were 0.17 to 0.26 mg/l for Cd, 34 to 63 mg/l for Cr, >3000 mg/l for acetone, 91-112 mg/l for atrazine and 83-119 mg/l for metolachlor. The equilibrium partitioning approach was used to extrapolate the results to total soil exposure and thus enable a sensitivity comparison to

  5. Early outbreak detection by linking health advice line calls to water distribution areas retrospectively demonstrated in a large waterborne outbreak of cryptosporidiosis in Sweden

    Directory of Open Access Journals (Sweden)

    Pär Bjelkmar

    2017-04-01

    Full Text Available Abstract Background In the winter and spring of 2011 a large outbreak of cryptosporidiosis occurred in Skellefteå municipality, Sweden. This study summarizes the outbreak investigation in terms of outbreak size, duration, clinical characteristics, possible source(s and the potential for earlier detection using calls to a health advice line. Methods The investigation included two epidemiological questionnaires and microbial analysis of samples from patients, water and other environmental sources. In addition, a retrospective study based on phone calls to a health advice line was performed by comparing patterns of phone calls between different water distribution areas. Results Our analyses showed that approximately 18,500 individuals were affected by a waterborne outbreak of cryptosporidiosis in Skellefteå in 2011. This makes it the second largest outbreak of cryptosporidiosis in Europe to date. Cryptosporidium hominis oocysts of subtype IbA10G2 were found in patient and sewage samples, but not in raw water or in drinking water, and the initial contamination source could not be determined. The outbreak went unnoticed to authorities for several months. The analysis of the calls to the health advice line provides strong indications early in the outbreak that it was linked to a particular water treatment plant. Conclusions We conclude that an earlier detection of the outbreak by linking calls to a health advice line to water distribution areas could have limited the outbreak substantially.

  6. pH-induced inversion of water-in-oil emulsions to oil-in-water high internal phase emulsions (HIPEs) using core cross-linked star (CCS) polymer as interfacial stabilizer.

    Science.gov (United States)

    Chen, Qijing; Deng, Xiaoyong; An, Zesheng

    2014-06-01

    A pH-responsive core cross-linked star (CCS) polymer containing poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) arms was used as an interfacial stabilizer for emulsions containing toluene (80 v%) and water (20 v%). In the pH range of 12.1-9.3, ordinary water-in-oil emulsions were formed. Intermediate multiple emulsions of oil-in-water-in-oil and water-in-oil-in-water were formed at pH 8.6 and 7.5, respectively. Further lowering the pH resulted in the formation of gelled high internal phase emulsions of oil-in-water type in the pH range of 6.4-0.6. The emulsion behavior was correlated with interfacial tension, conductivity and configuration of the CCS polymer at different pH. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Finding the gaps

    Science.gov (United States)

    Stoneham, A. M.

    Much of the pioneering work on radiation damage was based on very simple potentials. Potentials are now much more sophisticated and accurate. Self-consistent molecular dynamics is routine for adiabatic energy surfaces, at least for modest numbers of atoms and modest timescales. This means that non-equilibrium nuclear processes can be followed dynamically. It might also give the illusion that any damage process can be modelled with success. Sadly, this is not yet so. This paper discusses where the gaps lie, and specifically three groups of challenges. The first challenge concerns electronic excited states. The second challenge concerns timescales, from femtoseconds to tens of years. The third challenge concerns length scales, and the link between microscopic (atomistic) and mesoscopic (microstructural) scales. The context of these challenges is materials modification by excitation: the removal of material, the modification of bulk or surface material, the altering of rates of processes or changing of branching ratios, and damage, good or bad.

  8. River basins as social-ecological systems: linking levels of societal and ecosystem water metabolism in a semiarid watershed

    Directory of Open Access Journals (Sweden)

    Violeta Cabello

    2015-09-01

    Full Text Available River basin modeling under complexity requires analytical frameworks capable of dealing with the multiple scales and dimensions of environmental problems as well as uncertainty in the evolution of social systems. Conceptual and methodological developments can now be framed using the wide socio-eco-hydrological approach. We add hierarchy theory into the mix to discuss the conceptualization of river basins as complex, holarchic social-ecological systems. We operationalize the social-ecological systems water metabolism framework in a semiarid watershed in Spain, and add the governance dimension that shapes human-environment reciprocity. To this purpose, we integrate an eco-hydrological model with the societal metabolism accounting scheme for land use, human activity, and water use. We explore four types of interactions: between societal organization and water uses/demands, between ecosystem organization and their water requirements/supplies, between societal metabolism and aquatic ecosystem health, and between water demand and availability. Our results reveal a metabolic pattern of a high mountain rural system striving to face exodus and agricultural land abandonment with a multifunctional economy. Centuries of social-ecological evolution shaping waterscapes through traditional water management practices have influenced the eco-hydrological functioning of the basin, enabling adaptation to aridity. We found a marked spatial gradient on water supply, use pattern, and impact on water bodies from the head to the mouth of the basin. Management challenges posed by the European water regulatory framework as a new driver of social-ecological change are highlighted.

  9. Sustainable Water Management in the Tourism Economy: Linking the Mediterranean’s Traditional Rainwater Cisterns to Modern Needs

    Directory of Open Access Journals (Sweden)

    Jared Enriquez

    2017-11-01

    Full Text Available Communities on islands with mass-tourism, like Santorini, rely on vast quantities of water to develop the local economy. Today’s inhabitants of Santorini have largely abandoned the traditional cisterns that were used to sustain the island’s pre-modern civilizations in favor of water obtained from desalinization, ship deliveries, and well withdrawals. In June 2016, Cornell University researchers worked with the Water and Sewage Authority of Thera (DEYATH to assess the viability of improving sustainability and water efficiency by restoring traditional rainwater harvesting and storage cisterns. The team surveyed five cisterns, held meetings with water authority staff and mayoral leadership, conducted interviews with local tourism stakeholders, and coordinated with Global Water Partnership-Mediterranean. One conclusion was that cisterns could be rehabilitated as decentralized storage reservoirs and integrated into the island’s centralized water systems, or alternatively, serve as educational and cultural spaces used to communicate the importance of water to residents and tourists. The research findings highlight how multi-stakeholder partnerships could assist local authorities with developing new water management initiatives to foster more sustainable models of tourism development.

  10. Divergent NEE balances from manual-chamber CO2 fluxes linked to different measurement and gap-filling strategies: A source for uncertainty of estimated terrestrial C sources and sinks?

    DEFF Research Database (Denmark)

    Huth, Vytas; Vaidya, Shrijana; Hoffmann, Mathias

    2017-01-01

    Manual closed-chamber measurements are commonly used to quantify annual net CO2 ecosystem exchange (NEE) in a wide range of terrestrial ecosystems. However, differences in both the acquisition and gap filling of manual closed-chamber data are large in the existing literature, complicating inter...... measurements from sunrise to noon (sunrise approach) to capture a span of light conditions for measurements of NEE with transparent chambers. (2) The second level included three different methods of pooling measured ecosystem respiration (RECO) fluxes for empirical modeling of RECO: campaign-wise (19 single...... RECO fluxes (direct GPP modeling) or empirically modeled RECO fluxes from measured NEE fluxes (indirect GPP modeling). Measurements were made during 2013–2014 in a lucerne-clover-grass field in NE Germany. Across the different combinations of measurement and gap-filling options, the NEE balances...

  11. Macro-Micro Feedback Links of Water Management in South Africa : CGE Analyses of Selected Policy Regimes

    OpenAIRE

    Hassan, R.; Thurlow, J.; Roe, T.; Diao, X.; Chumi., S.; Tsur, Y.

    2008-01-01

    The pressure on an already stressed water situation in South Africa is predicted to increase significantly under climate change, plans for large industrial expansion, observed rapid urbanization, and government programs to provide access to water to millions of previously excluded people. The present study employed a general equilibrium approach to examine the economy-wide impacts of selec...

  12. Gains from trans-boundary water quality management in linked catchment and coastal socio-ecological systems: a case study for the Minho region

    Science.gov (United States)

    Roebeling, P. C.; Brito, A. G.; Rocha, J.; Alves, H.; Mamede, J.

    2012-04-01

    Worldwide, aquatic and coastal ecosystems are affected by point and diffuse source water pollution originating from rural, urban and industrial land uses in catchments, even though these ecosystems are of vital importance from an environmental and economic perspective. Integrated Catchment and Coastal Zone Management (ICCZM) specifically takes into account this inherent relationship between terrestrial land use, surface and ground water pollution, aquatic and coastal ecosystem state, and associated environmental values. To warrant sustainable regional economic development, we need to balance the marginal costs from terrestrial water pollution abatement and the associated marginal benefits from aquatic and coastal resource appreciation. In doing so, however, we need to differentiate between intra- and trans-boundary catchments because benefactors and beneficiaries from water quality improvement are not one and the same. In trans-boundary catchments, private (national) welfare maximizing rates of water quality improvement differ across nations as benefits from water quality improvement generally accrue to one nation while the costs are paid by multiple nations. While approaches for water quality management in linked catchment and coastal socio-ecological systems are fairly recent though existent, water quality management in trans-boundary catchments poses additional challenges. The objective of this paper is to develop and apply a deterministic optimal control approach that allows us to explore private and social welfare maximizing rates of water pollution abatement in linked catchment and coastal socio-ecological systems. For a case study of the Minho region in the Iberian Peninsula, we estimate nation-specific water pollution abatement cost (based on management practice adoption) and benefit (based on aquatic and coastal environmental values) functions, to determine as well as compare private (national) and social (trans-national) welfare maximizing rates of water

  13. Effect of cross-linking of interfacial sodium caseinate by natural processing on the oxidative stability of oil-in-water (o/w) emulsions.

    Science.gov (United States)

    Phoon, Pui Yeu; Paul, Lake N; Burgner, John W; San Martin-Gonzalez, M Fernanda; Narsimhan, Ganesan

    2014-04-02

    This study investigated how enzymatic cross-linking of interfacial sodium caseinate and emulsification, via high-pressure homogenization, influenced the intrinsic oxidative stability of 4% (w/v) menhaden oil-in-water emulsions stabilized by 1% (w/v) caseinate at pH 7. Oil oxidation was monitored by the ferric thiocyanate perioxide value assay. Higher homogenization pressure resulted in improved intrinsic emulsion oxidative stability, which is attributed to increased interfacial cross-linking as indicated by higher weighted average sedimentation coefficients of interfacial protein species (from 11.2 S for 0 kpsi/0.1 MPa to 18 S for 20 kpsi/137.9 MPa). Moderate dosage of transglutaminase at 0.5-1.0 U/mL emulsion enhanced intrinsic emulsion oxidative stability further, despite a contradictory reduction in the antioxidant property of cross-linked caseinate as tested by the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. This implied the prominent role of cross-linked interfacial caseinate as a physical barrier for oxygen transfer, hence its efficacy in retarding oil oxidation.

  14. An approach to link water resource management with landscape art to enhance its aesthetic appeal, ecological utility and social benefits

    Science.gov (United States)

    Mukherjee, Anita; Sen, Somnath; Paul, Saikat Kumar

    2017-04-01

    Landscape art or land art is the discourse of scientific application of artistic skill to integrate man-made structures with the natural landscape for planning, design, management, preservation and rehabilitation of natural and built environment. It does beautification of the landscape enhancing its utility for habitats. Availability of water with acceptable quality is crucial for economic growth, social peace and equality and of course for environmental sustainability. Development of new and growth of existing urban and suburban units are obvious. It postulates the increase of population density and percent of the impervious area in an urban unit. The demand for water is increasing with progressive concentration of population, the volume and velocity of surface runoff increase and the travel time decreases. At the same time, an increase in the volume of gray water not only contaminate water bodies, it also reduces the quantity of available freshwater transforming a portion of blue and green water to gray one and would intensify the pressure on water resources of the area. Therefore, to meet the incremental pressure of demand for and pollution of water collection, treatment and reuse of wastewater, both sewage and storm water, are on the requirement to improve urban water security. People must be concerned not to stifle urban lives with concrete; rather must provide all basic amenities for achieving a higher standard of life than the previous one with the essence of natural green spaces. The objective of the study is to propose a conceptual design and planning guidelines for developing urban and suburban drainage network and reuse of surface runoff and sewage water utilizing less used natural water bodies, such as paleo-channels or lakes or moribund channels as retention or detention basin. In addition to wastewater management, the proposal serves to promote the aesthetics of environmental engagement, ecological utility and restoration of moribund channels

  15. Evaluation of CDOM sources and their links with water quality in the lakes of Northeast China using fluorescence spectroscopy

    Science.gov (United States)

    Zhao, Ying; Song, Kaishan; Wen, Zhidan; Fang, Chong; Shang, Yingxin; Lv, Lili

    2017-07-01

    The spatial distributions of the fluorescence intensities Fmax for chromophoric dissolved organic matter (CDOM) components, the fluorescence indices (FI370 and FI310) and their correlations with water quality of 19 lakes in the Songhua River Basin (SHRB) across semiarid regions of Northeast China were examined with the data collected in September 2012 and 2015. The 19 lakes were divided into two groups according to EC (threshold value = 800 μS cm-1): fresh water (N = 13) and brackish water lakes (N = 6). The fluorescent characteristics of CDOM in the 19 lakes were investigated using excitation-emission matrix fluorescence spectroscopy (EEM) coupled with parallel factor (PARAFAC) and multivariate analysis. Two humic-like components (C1 and C3), one tryptophan-like component (C2), and one tyrosine-like component (C4) were identified by PARAFAC. The component C4 was not included in subsequent analyses due to the strong scatter in some colloidal water samples from brackish water lakes. The correlations between Fmax for the three EEM-PARAFAC extracted CDOM components C1-C3, the fluorescence indices (FI370 and FI310) and the water quality parameters (i.e., TN, TP, Chl-a, pH, EC, turbidity (Turb) and dissolved organic carbon (DOC)) were determined by redundancy analysis (RDA). The results of RDA analysis showed that spatial variation in land cover, pollution sources, and salinity/EC gradients in water quality affected Fmax for the fluorescent components C1-C3 and the fluorescence indices (FI370 and FI310). Further examination indicated that the CDOM fluorescent components and the fluorescence indices (FI370 and FI310) did not significantly differ (t-test, p > 0.05) in fresh water (N = 13) and brackish water lakes (N = 6). There was a difference in the distribution of the average Fmax for the CDOM fluorescent components between C1 to C3 from agricultural sources and urban wastewater sources in hypereutrophic brackish water lakes. The Fmax for humic-like components C1 and

  16. Determining the potential link between irrigation water quality and the microbiological quality of onions by phenotypic and genotypic characterization of Escherichia coli isolates.

    Science.gov (United States)

    du Plessis, Erika M; Duvenage, Francois; Korsten, Lise

    2015-04-01

    The potential transfer of human pathogenic bacteria present in irrigation water onto fresh produce was investigated, because surface water sources used for irrigation purposes in South Africa have increasingly been reported to be contaminated with enteric bacterial pathogens. A microbiological analysis was performed of a selected river in Limpopo Province, South Africa, that is often contaminated with raw sewage from municipal sewage works and overhead irrigated onions produced on a commercial farm. Counts of Escherichia coli, coliforms, aerobic bacteria, fungi, and yeasts and the prevalence of E. coli O157:H7, Salmonella, and Listeria monocytogenes were determined. Identities of bacterial isolates from irrigation water and onions were confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrometry, PCR, and biochemical tests. To establish a potential link between the microbiological quality of the irrigation source and the onions, the E. coli isolates from both were subjected to antibiotic resistance, virulence gene, and enterobacterial repetitive intergenic consensus PCR analyses. River water E. coli counts exceeded South African Department of Water Affairs and World Health Organization irrigation water guidelines. Counts of aerobic bacteria, coliforms, fungi, and yeasts of onions from the market were acceptable according to Department of Health Directorate, Food Control, South Africa, microbiological guidelines for ready-to-eat fresh fruits and vegetables. E. coli O157:H7, Salmonella, and L. monocytogenes were not detected in onions, whereas only Salmonella was detected in 22% of water samples. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and PCR identification of E. coli isolates from water and onions correlated. Of the 45 E. coli isolates from water and onions, 42.2% were resistant to multiple antibiotics. Virulence genes eae, stx1, and stx2 were detected in 2.2, 6.6, and 2.2% of the E. coli isolates

  17. Linking the Diffusion of Water in Compacted Clays at Two Different Time Scales: Tracer Through-Diffusion and QENS

    International Nuclear Information System (INIS)

    Juranyi, Fanni; Gonzalez Sanchez, Fatima; Gimmi, Thomas; Bestel, Martina; Van Loon, Luc; Diamond, Larryn W.

    2013-01-01

    Observable water diffusion processes in clays and their parameters depend on the spatial- and time-scale of the measurement. Comparing the diffusion coefficients of quasielastic neutron scattering and tracer through-diffusion, 'chemical' and 'geometrical' effects can be distinguished and quantified. Results for montmorillonite and illite in the Na- and Ca- form illustrate this very well. Swelling clays such as montmorillonite are especially interesting because of the interlayer water. This water is confined in form of few layers such that the diffusion occurs essentially in 2D. Furthermore the ratio of interlayer- and external- (macro-pore) water changes as a function of bulk dry density and degree of water saturation. Therefore it is of interest to describe the diffusion process using these parameters. Finally, the activation energy of the diffusion should be equal for both methods assuming that the geometrical factor does not depend on temperature. For the montmorillonites this was not the case, which might also indicate that the main processes on the two scales are different. We conclude that the geometrical factor and the electrostatic constraint can be determined from a comparison of the diffusion coefficients measured by the two different techniques: quasielastic neutron scattering and tracer through diffusion. Furthermore, activation energies obtained at the two scales are similar for clays having no interlayer water. For montmorillonite the activation energy values are different. Further investigations are required to clarify the reason. (authors)

  18. The Knowledge Gap Versus the Belief Gap and Abstinence-Only Sex Education.

    Science.gov (United States)

    Hindman, Douglas Blanks; Yan, Changmin

    2015-08-01

    The knowledge gap hypothesis predicts widening disparities in knowledge of heavily publicized public affairs issues among socioeconomic status groups. The belief gap hypothesis extends the knowledge gap hypothesis to account for knowledge and beliefs about politically contested issues based on empirically verifiable information. This analysis of 3 national surveys shows belief gaps developed between liberals and conservatives regarding abstinence-only sex education; socioeconomic status-based knowledge gaps did not widen. The findings partially support both belief gap and knowledge gap hypotheses. In addition, the unique contributions of exposure to Fox News, CNN, and MSNBC in this process were investigated. Only exposure to Fox News was linked to beliefs about abstinence-only sex education directly and indirectly through the cultivation of conservative ideology.

  19. Exploring links between water quality and E. coli O157:H7 survival potential in well waters from a rural area of southern Changchun City, China.

    Science.gov (United States)

    Ding, Meiyue; Li, Jiahang; Liu, Xiaodan; Li, Huiru; Zhang, Rui; Ma, Jincai

    2018-04-01

    Waterborne infectious disease outbreak associated with well water contamination is a worldwide public health issue, especially for rural areas in developing countries. In the current study, we characterized 20 well water samples collected from a rural area of southern Changchun city, China, and investigated the survival potential of Escherichia coli O157:H7 in those water samples. The results showed that nitrate and ammonia concentrations in some well water samples exceed the corresponding China drinking water standards, indicating potential contamination by local agricultural farms. Our results also revealed that the average survival time (ttd) of E. coli O157:H7 in all well water samples was 30.09 days, with shortest and longest ttd being 17.95 and 58.10 days, respectively. The ttds were significantly correlated with pH and the ratio of total nitrogen to total phosphorus. In addition, it was found that the shape parameter (p) and first decimal reduction parameter (δ) were negatively (P well water, suggesting that this pathogen could constitute a great public health risk.

  20. Variations of DOM quality in inflows of a drinking water reservoir: linking of van Krevelen diagrams with EEMF spectra by rank correlation.

    Science.gov (United States)

    Herzsprung, Peter; von Tümpling, Wolf; Hertkorn, Norbert; Harir, Mourad; Büttner, Olaf; Bravidor, Jenny; Friese, Kurt; Schmitt-Kopplin, Philippe

    2012-05-15

    Elevated concentrations of dissolved organic matter (DOM) such as humic substances in raw water pose significant challenges during the processing of the commercial drinking water supplies. This is a relevant issue in Saxony, Central East Germany, and many other regions worldwide, where drinking water is produced from raw waters with noticeable presence of chromophoric DOM (CDOM), which is assumed to originate from forested watersheds in spring regions of the catchment area. For improved comprehension of DOM molecular composition, the seasonal and spatial variations of humic-like fluorescence and elemental formulas in the catchment area of the Muldenberg reservoir were recorded by excitation emission matrix fluorescence (EEMF) and ultrahigh-resolution mass spectrometry (FT-ICR-MS). The Spearman rank correlation was applied to link the EEMF intensities with exact molecular formulas and their corresponding relative mass peak abundances. Thereby, humic-like fluorescence could be allocated to the pool of oxygen-rich and relatively unsaturated components with stoichiometries similar to those of tannic acids, which are suspected to have a comparatively high disinfection byproduct formation potential associated with the chlorination of raw water. Analogous relationships were established for UV absorption at 254 nm (UV(254)) and dissolved organic carbon (DOC) and compared to the EEMF correlation.

  1. Links Between the Deep Western Boundary Current, Labrador Sea Water Formation and Export, and the Meridional Overturning Circulation

    Science.gov (United States)

    Myers, Paul G.; Kulan, Nilgun

    2010-05-01

    Based on an isopyncal analysis of historical data, 3-year overlapping triad fields of objectively analysed temperature and salinity are produced for the Labrador Sea, covering 1949-1999. These fields are then used to spectrally nudge an eddy-permitting ocean general circulation model of the sub-polar gyre, otherwise forced by inter annually varying surface forcing based upon the Coordinated Ocean Reference Experiment (CORE). High frequency output from the reanalysis is used to examine Labrador Sea Water formation and its export. A number of different apprpoaches are used to estimate Labrador Sea Water formation, including an instanteous kinematic approach to calculate the annual rate of water mass subduction at a given density range. Historical transports are computed along sections at 53 and 56N for several different water masses for comparison with recent observations, showing a decline in the stength of the deep western boundary current with time. The variability of the strength of the meridional overturning circulation (MOC) from the reanalysis is also examined in both depth and density space. Linkages between MOC variability and water mass formation variability is considered.

  2. Uranium Speciation in Drinking Water from Drilled Wells in Southern Finland and Its Potential Links to Health Effects

    International Nuclear Information System (INIS)

    Prat, O.; Vercouter, Th.; Ansoborlo, E.; Fichet, P.; Perret, P.; Kurttio, P.; Salonen, L.

    2009-01-01

    Exceptionally high concentrations of natural uranium have been found in drinking water originating from drilled wells in Southern Finland. However, no clear clinical symptoms have been observed among the exposed population. Hence a question arose as to whether uranium speciation could be one reason for the lack of significant adverse health effects. Uranium species were determined using time-resolved laser-induced-fluorescence-spectroscopy. We performed multi-element chemical analyses in these water samples, and predictive calculations were carried out using up-to-date thermodynamic data. The results indicated good agreement between measurements and modeling. The low toxicity of Finnish bedrock water may be due to the predominance of two calcium dependent species, Ca 2 UO 2 (CO 3 ) 3 (aq) and CaUO 2 (CO 3 ) 3 2- , whose non toxicity for cells has been described previously. This interdisciplinary study describes chemical speciation of drinking water with elevated uranium concentrations and the potential consequence on health. From these results, it appears that modeling could be used for a better understanding of uranium toxicity of drinking water in the event of contamination. (authors)

  3. The prototype GAPS (pGAPS) experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mognet, S.A.I., E-mail: mognet@astro.ucla.edu [University of California, Los Angeles, CA 90095 (United States); Aramaki, T. [Columbia University, New York, NY 10027 (United States); Bando, N. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Boggs, S.E.; Doetinchem, P. von [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Fuke, H. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Gahbauer, F.H.; Hailey, C.J.; Koglin, J.E.; Madden, N. [Columbia University, New York, NY 10027 (United States); Mori, K.; Okazaki, S. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Ong, R.A. [University of California, Los Angeles, CA 90095 (United States); Perez, K.M.; Tajiri, G. [Columbia University, New York, NY 10027 (United States); Yoshida, T. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Zweerink, J. [University of California, Los Angeles, CA 90095 (United States)

    2014-01-21

    The General Antiparticle Spectrometer (GAPS) experiment is a novel approach for the detection of cosmic ray antiparticles. A prototype GAPS (pGAPS) experiment was successfully flown on a high-altitude balloon in June of 2012. The goals of the pGAPS experiment were: to test the operation of lithium drifted silicon (Si(Li)) detectors at balloon altitudes, to validate the thermal model and cooling concept needed for engineering of a full-size GAPS instrument, and to characterize cosmic ray and X-ray backgrounds. The instrument was launched from the Japan Aerospace Exploration Agency's (JAXA) Taiki Aerospace Research Field in Hokkaido, Japan. The flight lasted a total of 6 h, with over 3 h at float altitude (∼33km). Over one million cosmic ray triggers were recorded and all flight goals were met or exceeded.

  4. The prototype GAPS (pGAPS) experiment

    International Nuclear Information System (INIS)

    Mognet, S.A.I.; Aramaki, T.; Bando, N.; Boggs, S.E.; Doetinchem, P. von; Fuke, H.; Gahbauer, F.H.; Hailey, C.J.; Koglin, J.E.; Madden, N.; Mori, K.; Okazaki, S.; Ong, R.A.; Perez, K.M.; Tajiri, G.; Yoshida, T.; Zweerink, J.

    2014-01-01

    The General Antiparticle Spectrometer (GAPS) experiment is a novel approach for the detection of cosmic ray antiparticles. A prototype GAPS (pGAPS) experiment was successfully flown on a high-altitude balloon in June of 2012. The goals of the pGAPS experiment were: to test the operation of lithium drifted silicon (Si(Li)) detectors at balloon altitudes, to validate the thermal model and cooling concept needed for engineering of a full-size GAPS instrument, and to characterize cosmic ray and X-ray backgrounds. The instrument was launched from the Japan Aerospace Exploration Agency's (JAXA) Taiki Aerospace Research Field in Hokkaido, Japan. The flight lasted a total of 6 h, with over 3 h at float altitude (∼33km). Over one million cosmic ray triggers were recorded and all flight goals were met or exceeded

  5. [Usefulness of local health reports to link the incidence rate of diarrhea with the quality of drinking water].

    Science.gov (United States)

    Rodriguez-Alvarez, María S; Moraña, Liliana B; Salusso, María M; Gil, José; Seghezzo, Lucas

    2018-03-20

    In this study, we analyzed the reports of the health care center located in Vaqueros (Salta, Argentina) over an 8-month period. Moreover, we determined the concentration of Escherichia coli and Giardia spp. cysts in samples from four different drinking water sources. A statistical relationship between water quality and cases of diarrhea could not be found. However, using an odds ratio calculation, it was possible to determine that one of the studied drinking water systems acts as a protection factor in cases of diarrhea. The present work provides useful information for planning preventive measures by the local health system. Copyright © 2018 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Linking diverse nutrient patterns to different water masses within anticyclonic eddies in the upwelling system off Peru

    Science.gov (United States)

    Saranga José, Yonss; Dietze, Heiner; Oschlies, Andreas

    2017-03-01

    Ocean eddies can both trigger mixing (during their formation and decay) and effectively shield water encompassed from being exchanged with ambient water (throughout their lifetimes). These antagonistic effects of eddies complicate the interpretation of synoptic snapshots typically obtained by ship-based oceanographic measurement campaigns. Here we use a coupled physical-biogeochemical model to explore biogeochemical dynamics within anticyclonic eddies in the eastern tropical South Pacific Ocean. The goal is to understand the diverse biogeochemical patterns that have been observed at the subsurface layers of the anticyclonic eddies in this region. Our model results suggest that the diverse subsurface nutrient patterns within eddies are associated with the presence of water masses of different origins at different depths.

  7. Link Climate Effects to Surface Water Quality and Drinking Water Plant Adaptation - A Update on Hydroclimatic Province and WTP-ccam Model

    Science.gov (United States)

    Key points in this presentation are: (1) How and why hydroclimatic province can help precipitation projection for water program engineering and management, (2) Implications of initial research results and planned further monitoring / research activities, (3) Five adaptation t...

  8. School Segregation and Racial Academic Achievement Gaps

    Directory of Open Access Journals (Sweden)

    Sean F. Reardon

    2016-09-01

    Full Text Available Although it is clear that racial segregation is linked to academic achievement gaps, the mechanisms underlying this link have been debated since James Coleman published his eponymous 1966 report. In this paper, I examine sixteen distinct measures of segregation to determine which is most strongly associated with academic achievement gaps. I find clear evidence that one aspect of segregation in particular—the disparity in average school poverty rates between white and black students’ schools—is consistently the single most powerful correlate of achievement gaps, a pattern that holds in both bivariate and multivariate analyses. This implies that high-poverty schools are, on average, much less effective than lower-poverty schools and suggests that strategies that reduce the differential exposure of black, Hispanic, and white students to poor schoolmates may lead to meaningful reductions in academic achievement gaps.

  9. Linking of FRAP-T, FRAPCON and RELAP-4 codes for transient analysis and accidents of light water reactors fuel rods

    International Nuclear Information System (INIS)

    Marra Neto, A.; Silva, A.T. e; Sabundjian, G.; Freitas, R.L.; Neves Conti, T. das.

    1991-09-01

    The computer codes FRAP-T, FRAPCON and RELAP-4 have been linked for the fuel rod behavior analysis under transients and hypothetical accidents in light water reactors. The results calculated by thermal hydraulic code RELAP-4 give input in file format into the transient fuel analysis code FRAP-T. If the effect of fuel burnup is taken into account, the fuel performance code FRAPCON should provide the initial steady state data for thhe transient analysis. With the thermal hydraulic boundary conditions provided by RELAP-4 (MOD3), FRAP-T6 is used to analyse pressurized water reactor fuel rod behavior during the blowdown phase under large break loss of coolant accident conditions. Two cases have been analysed: without and with initialization from FRAPCON-2 steady state data. (author)

  10. Linking air and water transport in intact soils to macro-porosity by combining laboratory measurements and X-ray Computed Tomography

    DEFF Research Database (Denmark)

    Katuwal, Sheela; Norgaard, Trine; Møldrup, Per

    -porosity (R2 = 0.80 for air permeability: R2= 0.61 for 5% arrival time) and macro-porosity of the restricting layer (R2=0.83 for air permeability: R2= 0.71 for 5% arrival time) over air-filled porosity and all the correlations were positive. The high positive correlation these air and water transport...... functions with macro-porosity stressed the importance of continuity and tortuosity of pores in air, water and solute flow and transport through the soils. Negative correlations of air permeability, 5% arrival time of tracer and macro-porosity were obtained with bulk density whereas with other soil physical......With an objective to link the hydraulic properties of soil with the soil structural properties, air permeability and 5% arrival time of a conservative tracer was measured for large undisturbed soil columns from the same agricultural field. The same soil columns were scanned with a medical scanner...

  11. Current knowledge and future research directions to link soil health and water conservation in the Ogallala Aquifer region.

    Science.gov (United States)

    The Ogallala Aquifer is one of the largest freshwater aquifers in the world. It acts as a valuable resource in agriculture, animal production, and public water supplies across eight Great Plains states. However, with high irrigation demand, low recharge rates across most of the region, and extreme c...

  12. Exploring industry specific social welfare maximizing rates of water pollution abatement in linked terrestrial and marine ecosystems

    NARCIS (Netherlands)

    Roebeling, P.C.; Hendrix, E.M.T.; Grieken, van M.E.

    2009-01-01

    Marine ecosystems are severely affected by water pollution originating from coastal catchments, while these ecosystems are of vital importance from an environmental as well as an economic perspective. To warrant sustainable economic development of coastal regions, we need to balance the marginal

  13. Ecosystem engineering creates a direct nutritional link between 600-m deep cold-water coral mounds and surface productivity

    NARCIS (Netherlands)

    Soetaert, K.; Mohn, C.; Rengstorf, A.; Grehan, A.; Van Oevelen, D.

    2016-01-01

    Cold-water corals (CWCs) form large mounds on the seafloor that are hotspots of biodiversity in the deep sea, but it remains enigmatic how CWCs can thrive in this food-limited environment. Here, we infer from model simulations that the interaction between tidal currents and CWC-formed mounds induces

  14. Water use by black wattle (Acacia mearnsii): implications for the link between removal of invading trees and catchment streamflow response

    CSIR Research Space (South Africa)

    Dye, P

    2004-01-01

    Full Text Available vegetation covers. Author’s review shows that very high rates of total evaporation are possible from dense infestations of black waffle occurring in riparian zones, where there are no soil water deficits through the year. Annual total evaporation from...

  15. The links between global carbon, water and nutrient cycles in an urbanizing world — the case of coastal eutrophication

    NARCIS (Netherlands)

    Kroeze, C.; Hofstra, N.; Ivens, W.; Löhr, A.; Strokal, M.; Wijnen, van J.

    2013-01-01

    The natural cycles of carbon (C), nitrogen (N), phosphorus (P) and water have been disturbed substantially by human activities. Urbanizing coastal drainage basins and large river deltas are located at the interface of freshwater and coastal components of the larger earth system and the process of

  16. A linked lake system beneath Thwaites Glacier, West Antarctica reveals an efficient mechanism for subglacial water flow.

    Science.gov (United States)

    Smith, B. E.; Gourmelen, N.; Huth, A.; Joughin, I. R.

    2016-12-01

    In this presentation we show the results of a multi-sensor survey of a system of subglacial lakes beneath Thwaites Glacier, West Antarctica. This is the first substantial active (meaning draining or filling on annual time scales) lake system detected under the fast-flowing glaciers of the Amundsen Coast. Altimetry data show that over the 2013 calendar year, four subglacial lakes drained, essentially simultaneously, with the bulk of the drainage taking place over the course the first three months of the year. The largest of the lakes appears to have drained around 3.7 km3 of water, with the others each draining less than 1 km3. The high-resolution radar surveys conducted in this area by NASA's IceBridge program allow detailed analysis of the subglacial hydrologic potential, which shows that the potential map in this area is characterized by small closed basins that should not, under the common assumption that water flow is directed down the gradient of the hydropotential, allow long-range water transport. The lakes' discharge demonstrates that, at least in some cases, water can flow out of apparently closed hydropotential basins. Combining a basal-flow routing map with a map of basal melt production suggests that the largest drainage event could recur as often as every 22 years, provided that overflow or leakage of mapped hydropotential basins allows melt water transport to refill the lake. An analysis of ice-surface speed records both around the lakes and at the Thwaites grounding line shows small changes in ice speed, but none clearly associated with the drainage event, suggesting that, at least in this area where subglacial melt is abundant, the addition of further water to the subglacial hydrologic system need not have any significant effect on ice flow. It is likely that the main impact of the lake system on the glacier is that as an efficient mechanism to remove meltwater from the system, it drains water that would otherwise flow through less efficient

  17. Linking hard and soft traits: Physiology, morphology and anatomy interact to determine habitat affinities to soil water availability in herbaceous dicots.

    Science.gov (United States)

    Belluau, Michaël; Shipley, Bill

    2018-01-01

    Species' habitat affinities along environmental gradients should be determined by a combination of physiological (hard) and morpho-anatomical (soft) traits. Using a gradient of soil water availability, we address three questions: How well can we predict habitat affinities from hard traits, from soft traits, and from a combination of the two? How well can we predict species' physiological responses to drought (hard traits) from their soft traits? Can we model a causal sequence as soft traits → hard traits → species distributions? We chose 25 species of herbaceous dicots whose affinities for soil moisture have already been linked to 5 physiological traits (stomatal conductance and net photosynthesis measured at soil field capacity, water use efficiency, stomatal conductance and soil water potential measured when leaves begin to wilt). Under controlled conditions in soils at field capacity, we measured five soft traits (leaf dry matter content, specific leaf area, leaf nitrogen content, stomatal area, specific root length). Soft traits alone were poor predictors (R2 = 0.129) while hard traits explained 48% of species habitat affinities. Moreover, hard traits were significantly related to combinations of soft traits. From a priori biological knowledge and hypothesized ecological links we built a path model showing a sequential pattern soft traits → hard traits → species distributions and accounting for 59.6% (p = 0.782) of habitat wetness. Both direct and indirect causal relationships existed between soft traits, hard traits and species' habitat preferences. The poor predictive abilities of soft traits alone were due to the existence of antagonistic and synergistic direct and indirect effects of soft traits on habitat preferences mediated by the hard traits. To obtain a more realistic model applicable to a population level, it has to be tested in an experiment including species competition for water supply.

  18. Linking River Basin Modifications and Rural Soil and Water Management Practices in Tropical Deltas to Sea Level Rise Vulnerability

    Science.gov (United States)

    Rogers, K. G.; Brondizio, E.; Roy, K.; Syvitski, J. P.

    2015-12-01

    The increased vulnerability of deltaic communities to coastal flooding as a result of upstream engineering has been acknowledged for decades. What has received less attention is the sensitivity of deltas to the interactions between river basin modifications and local scale cultivation and irrigation. Combined with reduced river and sediment discharge, soil and water management practices in coastal areas may exacerbate the risk of tidal flooding, erosion of arable land, and salinization of soils and groundwater associated with sea level rise. This represents a cruel irony to smallholder subsistence farmers whose priorities are food, water and economic security, rather than sustainability of the environment. Such issues challenge disciplinary approaches and require integrated social-biophysical models able to understand and diagnose these complex relationships. This study applies a new conceptual framework to define the relevant social and physical units operating on the common pool resources of climate, water and sediment in the Bengal Delta (Bangladesh). The new framework will inform development of a nested geospatial analysis and a coupled model to identify multi-scale social-biophysical feedbacks associated with smallholder soil and water management practices, coastal dynamics, basin modification, and climate vulnerability in tropical deltas. The framework was used to create household surveys for collecting data on climate perceptions, land and water management, and governance. Test surveys were administered to rural farmers in 14 villages during a reconnaissance visit to coastal Bangladesh. Initial results demonstrate complexity and heterogeneity at the local scale in both biophysical conditions and decision-making. More importantly, the results illuminate how national and geopolitical-level policies scale down to impact local-level environmental and social stability in communities already vulnerable to coastal flooding. Here, we will discuss components of the

  19. Linking land use changes to surface water quality variability in Lake Victoria: some insights from remote sensing

    Science.gov (United States)

    Mugo, R. M.; Limaye, A. S.; Nyaga, J. W.; Farah, H.; Wahome, A.; Flores, A.

    2016-12-01

    The water quality of inland lakes is largely influenced by land use and land cover changes within the lake's catchment. In Africa, some of the major land use changes are driven by a number of factors, which include urbanization, intensification of agricultural practices, unsustainable farm management practices, deforestation, land fragmentation and degradation. Often, the impacts of these factors are observable on changes in the land cover, and eventually in the hydrological systems. When the natural vegetation cover is reduced or changed, the surface water flow patterns, water and nutrient retention capacities are also changed. This can lead to high nutrient inputs into lakes, leading to eutrophication, siltation and infestation of floating aquatic vegetation. To assess the relationship between land use and land cover changes in part of the Lake Victoria Basin, a series of land cover maps were derived from Landsat imagery. Changes in land cover were identified through change maps and statistics. Further, the surface water chlorophyll-a concentration and turbidity were derived from MODIS-Aqua data for Lake Victoria. Chlrophyll-a and turbidity are good proxy indicators of nutrient inputs and siltation respectively. The trends in chlorophyll-a and turbidity concentrations were analyzed and compared to the land cover changes over time. Certain land cover changes related to agriculture and urban development were clearly identifiable. While these changes might not be solely responsible for variability in chlrophyll-a and turbidity concentrations in the lake, they are potentially contributing factors to this problem. This work illustrates the importance of addressing watershed degradation while seeking to solve water quality related problems.

  20. Beyond the Dams: Linking Rural Smallholder Soil and Water Management Practices in Tropical Deltas to Sea Level Rise Vulnerability

    Science.gov (United States)

    Rogers, K. G.; Syvitski, J. P.; Brondizio, E. S.

    2014-12-01

    The increased vulnerability of deltaic communities to coastal flooding as a result of upstream engineering has been acknowledged for decades. What has received less attention is the sensitivity of deltas to the interactions of river basin modifications and cultivation and irrigation in their coastal regions, particularly in tropical deltas. Embanking, tilling, and crop or stock choice all affect the movement of sediment and water on deltas. Combined with reduced river and sediment discharge, soil and water management practices in coastal areas may in fact exacerbate the risk of tidal flooding, erosion of arable land, and salinization of soils and groundwater associated with sea level rise. Thus exists a cruel irony to smallholder subsistence farmers whose priorities are food, water and economic security, rather than sustainability of the regional environment. Such issues challenge disciplinary approaches and require integrated social-biophysical models able to understand and diagnose these complex relationships. The complementary Institutional Analysis and Development and SocioEcological Systems frameworks are applied to the southwestern Bengal Delta (Bangladesh). The method helps to define the relevant social and physical units operating on the common pool of environmental resources, those of climate, water and sediment. The conceptual frameworks are designed to inform development of a nested geospatial analysis and a dynamic coupled model to identify the social-biophysical feedbacks associated with smallholder soil and water management practices, coastal dynamics, and climate vulnerability in rural Bangladesh. Our presentation will discuss components of the conceptual frameworks and will introduce a bi-directional pilot study designed for obtaining and disseminating information about environmental change to farmers in southwest Bangladesh with potential application to rural farming communities in other tropical deltas.

  1. Paradigm Shift in Transboundary Water Management Policy: Linking Water Environment Energy and Food (weef) to Catchment Hydropolitics - Needs, Scope and Benefits

    Science.gov (United States)

    RAI, S.; Wolf, A.; Sharma, N.; Tiwari, H.

    2015-12-01

    The incessant use of water due to rapid growth of population, enhanced agricultural and industrial activities, degraded environment and ecology will in the coming decades constrain the socioeconomic development of humans. To add on to the precarious situation, political boundaries rarely embrace hydrological boundaries of lakes, rivers, aquifers etc. Hydropolitics relate to the ability of geopolitical institutions to manage shared water resources in a politically sustainable manner, i.e., without tensions or conflict between political entities. Riparian hydropolitics caters to differing objectives, needs and requirements of states making it difficult to administer the catchment. The diverse riparian objectives can be merged to form a holistic catchment objective of sustainable water resources development and management. It can be proposed to make a paradigm shift in the present-day transboundary water policy from riparian hydropolitics (in which the focal point of water resources use is hinged on state's need) to catchment hydropolitics (in which the interest of the basin inhabitants are accorded primacy holistically over state interests) and specifically wherein the water, environment, energy and food (WEEF) demands of the catchment are a priority and not of the states in particular. The demands of the basin pertaining to water, food and energy have to be fulfilled, keeping the environment and ecology healthy in a cooperative political framework; the need for which is overwhelming. In the present scenario, the policy for water resources development of a basin is segmented into independent uncoordinated parts controlled by various riparians; whereas in catchment hydropolitics the whole basin should be considered as a unit. The riparians should compromise a part of national interest and work in collaboration on a joint objective which works on the principle of the whole as against the part. Catchment hydropolitics may find greater interest in the more than 250

  2. Thermodynamic analysis of the use a chemical heat pump to link a supercritical water-cooled nuclear reactor and a thermochemical water-splitting cycle for hydrogen production

    International Nuclear Information System (INIS)

    Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.; Pioro, Igor

    2008-01-01

    Increases in the power generation efficiency of nuclear power plants (NPPs) are mainly limited by the permissible temperatures in nuclear reactors and the corresponding temperatures and pressures of the coolants in reactors. Coolant parameters are limited by the corrosion rates of materials and nuclear-reactor safety constraints. The advanced construction materials for the next generation of CANDU reactors, which employ supercritical water (SCW) as a coolant and heat carrier, permit improved 'steam' parameters (outlet temperatures up to 625degC and pressures of about 25 MPa). An increase in the temperature of steam allows it to be utilized in thermochemical water splitting cycles to produce hydrogen. These methods are considered by many to be among the most efficient ways to produce hydrogen from water and to have advantages over traditional low-temperature water electrolysis. However, even lower temperature water splitting cycles (Cu-Cl, UT-3, etc.) require an intensive heat supply at temperatures higher than 550-600degC. A sufficient increase in the heat transfer from the nuclear reactor to a thermochemical water splitting cycle, without jeopardizing nuclear reactor safety, might be effectively achieved by application of a heat pump, which increases the temperature of the heat supplied by virtue of a cyclic process driven by mechanical or electrical work. Here, a high-temperature chemical heat pump, which employs the reversible catalytic methane conversion reaction, is proposed. The reaction shift from exothermic to endothermic and back is achieved by a change of the steam concentration in the reaction mixture. This heat pump, coupled with the second steam cycle of a SCW nuclear power generation plant on one side and a thermochemical water splitting cycle on the other, increases the temperature of the 'nuclear' heat and, consequently, the intensity of heat transfer into the water splitting cycle. A comparative preliminary thermodynamic analysis is conducted of

  3. Columbia River Component Data Gap Analysis

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Hulstrom

    2007-10-23

    This Data Gap Analysis report documents the results of a study conducted by Washington Closure Hanford (WCH) to compile and reivew the currently available surface water and sediment data for the Columbia River near and downstream of the Hanford Site. This Data Gap Analysis study was conducted to review the adequacy of the existing surface water and sediment data set from the Columbia River, with specific reference to the use of the data in future site characterization and screening level risk assessments.

  4. Estimating soil water-holding capacities by linking the Food and Agriculture Organization Soil map of the world with global pedon databases and continuous pedotransfer functions

    Science.gov (United States)

    Reynolds, C. A.; Jackson, T. J.; Rawls, W. J.

    2000-12-01

    Spatial soil water-holding capacities were estimated for the Food and Agriculture Organization (FAO) digital Soil Map of the World (SMW) by employing continuous pedotransfer functions (PTF) within global pedon databases and linking these results to the SMW. The procedure first estimated representative soil properties for the FAO soil units by statistical analyses and taxotransfer depth algorithms [Food and Agriculture Organization (FAO), 1996]. The representative soil properties estimated for two layers of depths (0-30 and 30-100 cm) included particle-size distribution, dominant soil texture, organic carbon content, coarse fragments, bulk density, and porosity. After representative soil properties for the FAO soil units were estimated, these values were substituted into three different pedotransfer functions (PTF) models by Rawls et al. [1982], Saxton et al. [1986], and Batjes [1996a]. The Saxton PTF model was finally selected to calculate available water content because it only required particle-size distribution data and results closely agreed with the Rawls and Batjes PTF models that used both particle-size distribution and organic matter data. Soil water-holding capacities were then estimated by multiplying the available water content by the soil layer thickness and integrating over an effective crop root depth of 1 m or less (i.e., encountered shallow impermeable layers) and another soil depth data layer of 2.5 m or less.

  5. Long-term study of migration of volatile organic compounds from cross-linked polyethylene (PEX) pipes and effects on drinking water quality.

    Science.gov (United States)

    Lund, Vidar; Anderson-Glenna, Mary; Skjevrak, Ingun; Steffensen, Inger-Lise

    2011-09-01

    The objectives of this study were to investigate migration of volatile organic compounds (VOCs) from cross-linked polyethylene (PEX) pipes used for drinking water produced by different production methods, and to evaluate their potential risk for human health and/or influence on aesthetic drinking water quality. The migration tests were carried out in accordance with EN-1420-1, and VOCs were analysed by gas chromatography-mass spectrometry. The levels of VOC migrating from new PEX pipes were generally low, and decreasing with time of pipe use. No association was found between production method of PEX pipes and concentration of migration products. 2,4-di-tert-butyl phenol and methyl tert-butyl ether (MTBE) were two of the major individual components detected. In three new PEX pipes, MTBE was detected in concentrations above the recommended US EPA taste and odour value for drinking water, but decreased below this value after 5 months in service. However, the threshold odour number (TON) values for two pipes were similar to new pipes even after 1 year in use. For seven chemicals for which conclusions on potential health risk could be drawn, this was considered of no or very low concern. However, odour from some of these pipes could negatively affect drinking water for up to 1 year.

  6. Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

    Directory of Open Access Journals (Sweden)

    Élise Euvrard

    2016-08-01

    Full Text Available In this study, a polymer, prepared by crosslinking cyclodextrin (CD by means of a polycarboxylic acid, was used for the removal of pollutants from spiked solutions and discharge waters from the surface treatment industry. In spiked solutions containing five metals, sixteen polycyclic aromatic hydrocarbons (PAH and three alkylphenols (AP, the material exhibited high adsorption capacities: >99% of Co2+, Ni2+ and Zn2+ were removed, between 65 and 82% of the PAHs, as well as 69 to 90% of the APs. Due to the structure of the polymer and its specific characteristics, such as the presence of carboxylic groups and CD cavities, the adsorption mechanism involves four main interactions: ion exchange, electrostatic interactions and precipitation for metal removal, and inclusion complexes for organics removal. In industrial discharge waters, competition effects appeared, especially because of the presence of calcium at high concentrations, which competed with other pollutants for the adsorption sites of the adsorbent.

  7. Ecosystem engineering creates a direct nutritional link between 600-m deep cold-water coral mounds and surface productivity

    Science.gov (United States)

    Soetaert, Karline; Mohn, Christian; Rengstorf, Anna; Grehan, Anthony; van Oevelen, Dick

    2016-10-01

    Cold-water corals (CWCs) form large mounds on the seafloor that are hotspots of biodiversity in the deep sea, but it remains enigmatic how CWCs can thrive in this food-limited environment. Here, we infer from model simulations that the interaction between tidal currents and CWC-formed mounds induces downwelling events of surface water that brings organic matter to 600-m deep CWCs. This positive feedback between CWC growth on carbonate mounds and enhanced food supply is essential for their sustenance in the deep sea and represents an example of ecosystem engineering of unparalleled magnitude. This ’topographically-enhanced carbon pump’ leaks organic matter that settles at greater depths. The ubiquitous presence of biogenic and geological topographies along ocean margins suggests that carbon sequestration through this pump is of global importance. These results indicate that enhanced stratification and lower surface productivity, both expected consequences of climate change, may negatively impact the energy balance of CWCs.

  8. Release of drinking water contaminants and odor impacts caused by green building cross-linked polyethylene (PEX) plumbing systems.

    Science.gov (United States)

    Kelley, Keven M; Stenson, Alexandra C; Dey, Rajarashi; Whelton, Andrew J

    2014-12-15

    Green buildings are increasingly being plumbed with crosslinked polyethylene (PEX) potable water pipe. Tap water quality was investigated at a six month old plumbing system and chemical and odor quality impacts of six PEX pipe brands were examined. Eleven PEX related contaminants were found in the plumbing system; one regulated (toluene) and several unregulated: Antioxidant degradation products, resin solvents, initiator degradation products, or manufacturing aides. Water chemical and odor quality was monitored for new PEX-a, -b and -c pipes with (2 mg/L free chlorine) and without disinfectant over 30 days. Odor and total organic carbon (TOC) levels decreased for all pipes, but odor remained greater than the USA's Environmental Protection Agency's (USEPA) secondary maximum contaminant level. Odors were not attributed to known odorants ethyl-tert-butyl ether (ETBE) or methyl-tert-butyl ether (MTBE). Free chlorine caused odor levels for PEX-a1 pipe to increase from 26 to 75 threshold odor number (TON) on day 3 and affected the rate at which TOC changed for each brand over 30 days. As TOC decreased, the ultraviolet absorbance at 254 nm increased. Pipes consumed as much as 0.5 mg/L as Cl2 during each 3 day stagnation period. Sixteen organic chemicals were identified, including toluene, pyridine, methylene trichloroacetate and 2,4-di-tert-butylphenol. Some were also detected during the plumbing system field investigation. Six brands of PEX pipes sold in the USA and a PEX-a green building plumbing system impacted chemical and drinking water odor quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Incidence of plasmid-linked antibiotic-heavy metal resistant enterics in water-sediment from agricultural and harbor sites

    Energy Technology Data Exchange (ETDEWEB)

    Mietz, J.A.; Sjorgren, R.E.

    1983-01-01

    This study assesses the impact of antibiotics used in clinical and veterinary practices on the incidence of antibiotic-heavy metal resistant enterics in fresh water and sediment from agricultural and harbor sample sites. A total of 848 bacterial strains of the family Enterobacteriaceae was isolated from agricultural and lake harbor samples. These were examined for anitbiotic-heavy metal resistance. A select smaller number of these isolates were also examined for the presence of plasmids and ability to transfer antibiotic resistance via conjugation or transformation. More than 85% of the 848 isolates from all four sites were resistant to Pb, Zn, and Co while 5.6% to 16% were resistant to Te and 2.4% to 5.7% to Hg. Of the total isolates tested, 87% were resistant to six or more antibiotics and 74% were also simultaneously resistant to Co, Zn, and Pb. Testing the resistance of the water isolates to antibiotics used solely in animal husbandry-veterinary medicine indicated that 55.6% of the agricultural isolates possessed resistance to these antibiotics while only 31.9% of the isolates from harbor water showed resistance to the same antibiotics. Of 41 ampicillin resistant isolates examined, 16 (39%) were capable of transferring antibiotic-heavy resistance markers via conjugation. From this same group, plasmid DNA preparations were made. Of these latter preparations, 67% transformed recipient E. coli cells while 58% possessed discernible, often multiple plasmids when examined by gel electrophoresis.

  10. Gas exchange at whole plant level shows that a less conservative water use is linked to a higher performance in three ecologically distinct pine species

    Science.gov (United States)

    Salazar-Tortosa, D.; Castro, J.; Rubio de Casas, R.; Viñegla, B.; Sánchez-Cañete, E. P.; Villar-Salvador, P.

    2018-04-01

    Increasing temperatures and decreasing precipitation in large areas of the planet as a consequence of global warming will affect plant growth and survival. However, the impact of climatic conditions will differ across species depending on their stomatal response to increasing aridity, as this will ultimately affect the balance between carbon assimilation and water loss. In this study, we monitored gas exchange, growth and survival in saplings of three widely distributed European pine species (Pinus halepensis, P. nigra and P. sylvestris) with contrasting distribution and ecological requirements in order to ascertain the relationship between stomatal control and plant performance. The experiment was conducted in a common garden environment resembling rainfall and temperature conditions that two of the three species are expected to encounter in the near future. In addition, gas exchange was monitored both at the leaf and at the whole-plant level using a transient-state closed chamber, which allowed us to model the response of the whole plant to increased air evaporative demand (AED). P. sylvestris was the species with lowest survival and performance. By contrast, P. halepensis showed no mortality, much higher growth (two orders of magnitude), carbon assimilation (ca. 14 fold higher) and stomatal conductance and water transpiration (ca. 4 fold higher) than the other two species. As a consequence, P. halepensis exhibited higher values of water-use efficiency than the rest of the species even at the highest values of AED. Overall, the results strongly support that the weaker stomatal control of P. halepensis, which is linked to lower stem water potential, enabled this species to maximize carbon uptake under drought stress and ultimately outperform the more water conservative P. nigra and P. sylvestris. These results suggest that under a hotter drought scenario P. nigra and P. sylvestris would very likely suffer increased mortality, whereas P. halepensis could maintain

  11. Behind the Pay Gap

    Science.gov (United States)

    Dey, Judy Goldberg; Hill, Catherine

    2007-01-01

    Women have made remarkable gains in education during the past three decades, yet these achievements have resulted in only modest improvements in pay equity. The gender pay gap has become a fixture of the U.S. workplace and is so ubiquitous that many simply view it as normal. "Behind the Pay Gap" examines the gender pay gap for college graduates.…

  12. The impacts of neutralized acid mine drainage contaminated water on the expression of selected endocrine-linked genes in juvenile Mozambique tilapia Oreochromis mossambicus exposed in vivo.

    Science.gov (United States)

    Truter, Johannes Christoff; va Wyk, Johannes Hendrik; Oberholster, Paul Johan; Botha, Anna-Maria

    2014-02-01

    Acid mine drainage (AMD) is a global environmental concern due to detrimental impacts on river ecosystems. Little is however known regarding the biological impacts of neutralized AMD on aquatic vertebrates despite excessive discharge into watercourses. The aim of this investigation was to evaluate the endocrine modulatory potential of neutralized AMD, using molecular biomarkers in the teleost fish Oreochromis mossambicus in exposure studies. Surface water was collected from six locations downstream of a high density sludge (HDS) AMD treatment plant and a reference site unimpacted by AMD. The concentrations of 28 elements, including 22 metals, were quantified in the exposure water in order to identify potential links to altered gene expression. Relatively high concentrations of manganese (~ 10mg/l), nickel (~ 0.1mg/l) and cobalt (~ 0.03 mg/l) were detected downstream of the HDS plant. The expression of thyroid receptor-α (trα), trβ, androgen receptor-1 (ar1), ar2, glucocorticoid receptor-1 (gr1), gr2, mineralocorticoid receptor (mr) and aromatase (cyp19a1b) was quantified in juvenile fish after 48 h exposure. Slight but significant changes were observed in the expression of gr1 and mr in fish exposed to water collected directly downstream of the HDS plant, consisting of approximately 95 percent neutralized AMD. The most pronounced alterations in gene expression (i.e. trα, trβ, gr1, gr2, ar1 and mr) was associated with water collected further downstream at a location with no other apparent contamination vectors apart from the neutralized AMD. The altered gene expression associated with the "downstream" locality coincided with higher concentrations of certain metals relative to the locality adjacent to the HDS plant which may indicate a causative link. The current study provides evidence of endocrine disruptive activity associated with neutralized AMD contamination in regard to alterations in the expression of key genes linked to the thyroid, interrenal and

  13. Molar ratios of therapeutic water-soluble phenothiazine⋅water-insoluble phospholipid adducts reveal a Fibonacci correlation and a putative link for structure–activity relationships

    DEFF Research Database (Denmark)

    Keyzer, Hendrik; Fey, S. J.; Thornton, Barry

    2015-01-01

    1,2diacyl-sn-glycero-3-phospholipids (PL) with even-numbered symmetric saturated diacyl chains with the headgroups choline (PC), glycerol (PG), serine (PS), ethanolamine (PE), phosphatidic acid (PA). We observed water soluble products with replicable molar ratios (MR) that could be divided into two...

  14. Linking benthic hydrodynamics and cold-water coral occurrences: A high-resolution model study at three cold-water coral provinces in the NE Atlantic

    NARCIS (Netherlands)

    Mohn, C.; Rengstorf, A.; White, M.; Mienis, F.; Soetaert, K.; Grehan, A.; Duineveld, G.

    2014-01-01

    Observations from numerous cold-water coral locations in the NE Atlantic show energetic near-bottom flow dynamics along the European continental margin at individual coral mounds and mound clusters. Dynamics are largely controlled by tide-topography interaction generating and enhancing periodic

  15. Uranium contaminated drinking water linked to leukaemia-Revisiting a case study from South Africa taking alternative exposure pathways into account.

    Science.gov (United States)

    Winde, Frank; Erasmus, Ewald; Geipel, Gerhard

    2017-01-01

    The paper presents results of a follow-up to an earlier study which established a geospatial link between naturally elevated uranium (U) levels in borehole water and haematological abnormalities in local residents serving as a proxy for leukaemia prevalent in the area. While the original study focussed on drinking water only, this paper also explores alternative exposure pathways including the inhalation of dust and the food chain. U-levels in grass and tissue of sheep generally reflect U-levels in nearby borehole water and exceed background concentrations by 20 to nearly 500 times. U-levels in sheep tissue increase with age of the animal. Wool showed the highest U-concentration followed by other non-consumable tissue such as hooves, teeth and bones. Lower levels occur in edible parts such as meat and inner organs. The U-deposition rate in wool is several orders of magnitudes higher than in bone as a known target organ. Wool is an easy-to-sample non-invasive bioindicator for U-levels in meat. Depending on the original water content, dried samples show up to 5 times higher U-levels than identical fresh material. Contaminated drinking water is the main exposure pathway for farm residents resulting in U-uptake rates exceeding the WHO's tolerable daily intake (TDI) limit by up to 900%. This is somewhat mitigated by the fact that U-speciation is dominated by a neutral calcium-uranyl-carbonate complex of relatively low toxicity. Commercially available household filters are able to significantly reduce U-levels in well water and are thus recommended as a short-term intervention. Based on average consumption rates sheep meat, as local staple food, accounts for 34% of the TDI for U. Indoor levels of radon should be monitored, too, since it is linked to both, U and leukaemia. With elevated U-levels being present in other geological formations across South Africa boreholes in these areas should be surveyed. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Exploring the links between water, sanitation and hygiene and disability; Results from a case-control study in Guatemala.

    Science.gov (United States)

    Kuper, Hannah; Mactaggart, Islay; White, Sian; Dionicio, Carlos; Cañas, Rafael; Naber, Jonathan; Polack, Sarah; Biran, Adam

    2018-01-01

    To assess the Water, Sanitation and Hygiene (WASH) access and appropriateness of people with disabilities compared to those without, in Guatemala. A case-control study was conducted, nested within a national survey. The study included 707 people with disabilities, and 465 age- and sex-matched controls without disabilities. Participants reported on WASH access at the household and individual level. A sub-set of 121 cases and 104 controls completed a newly designed, in-depth WASH questionnaire. Households including people with disabilities were more likely to use an improved sanitation facility compared to control households (age-sex-adjusted OR: 1.7, 95% CI 1.3-2.5), but otherwise there were no differences in WASH access at the household level. At the individual level, people with disabilities reported greater difficulties in relation to sanitation (mean score 26.2, SD 26.5) and hygiene access and quality (mean 30.7, SD 24.2) compared to those without disabilities (15.5, 21.7, p<0.001; 22.4, 19.1, p<0.01). There were no differences in different aspects of water collection between people with and without disabilities in this context where over 85% of participants had water piped into their dwelling. Among people with disabilities, older adults were more likely to experience difficulties in hygiene and sanitation than younger people with disabilities. People with disabilities in Guatemala experience greater difficulties in accessing sanitation facilities and practicing hygienic behaviours than their peers without disabilities. More data collection is needed using detailed tools to detect these differences, highlight which interventions are needed, and to allow assessment of their effectiveness.

  17. Exploring the links between transient water inputs and glacier velocity in a small temperate glacier in southeastern Alaska

    Science.gov (United States)

    Heavner, M.; Habermann, M.; Hood, E. W.; Fatland, D. R.

    2009-12-01

    Glaciers along the Gulf of Alaska are thinning and retreating rapidly. An important control on the rate at which ice is being lost is basal motion because higher glacier velocities increase the rate at which ice is delivered to ablation zones. Recent research has focused on understanding the effects of sub-glacial water storage on glacier basal motion. In this study, we examined two seasons of the effect of hydrologic controls (from large rainfall events as well as a glacier lake outburst floods) on the velocity of the Lemon Creek Glacier in southeastern Alaska. Lemon Creek Glacier is a moderately sized (~16~km2) temperate glacier at the margin of the Juneau Icefield. An ice-marginal lake forms at the head of the glacier and catastrophically drains once or twice every melt season. We have instrumented the glacier with two meteorological stations: one at the head of the glacier near the ice-marginal lake and another several kilometers below the terminus. These stations measure temperature, relative humidity, precipitation, incoming solar radiation and wind speed and direction. Lake stage in the ice-marginal lake was monitored with a pressure transducer. In addition, Lemon Creek was instrumented with a water quality sonde at the location of a US Geological Survey gaging station approximately 3 km downstream from the glacier terminus. The sonde provides continuous measurements of water temperature, dissolved oxygen, turbidity and conductivity. Finally, multiple Trimble NetRS dual frequency, differential GPS units were deployed on the glacier along the centerline of the glacier. All of the instruments were run continuously from May-September 2008 and May-September 2009 and captured threee outburst floods associated with the ice-marginal lake drainage as well as several large (>3~cm) rainfall events associated with frontal storms off of the Gulf of Alaska in late summer. Taken together, these data allow us to test the hypothesis that water inputs which overwhelm

  18. Water-carbon Links in a Tropical Forest: How Interbasin Groundwater Flow Affects Carbon Fluxes and Ecosystem Carbon Budgets

    Energy Technology Data Exchange (ETDEWEB)

    Genereux, David [North Carolina State Univ., Raleigh, NC (United States); Osburn, Christopher [North Carolina State Univ., Raleigh, NC (United States); Oberbauer, Steven [Florida Intl Univ., Miami, FL (United States); Oviedo Vargas, Diana [North Carolina State Univ., Raleigh, NC (United States); Dierick, Diego [Florida Intl Univ., Miami, FL (United States)

    2017-03-27

    This report covers the outcomes from a quantitative, interdisciplinary field investigation of how carbon fluxes and budgets in a lowland tropical rainforest are affected by the discharge of old regional groundwater into streams, springs, and wetlands in the forest. The work was carried out in a lowland rainforest of Costa Rica, at La Selva Biological Station. The research shows that discharge of regional groundwater high in dissolved carbon dioxide represents a significant input of carbon to the rainforest "from below", an input that is on average larger than the carbon input "from above" from the atmosphere. A stream receiving discharge of regional groundwater had greatly elevated emissions of carbon dioxide (but not methane) to the overlying air, and elevated downstream export of carbon from its watershed with stream flow. The emission of deep geological carbon dioxide from stream water elevates the carbon dioxide concentrations in air above the streams. Carbon-14 tracing revealed the presence of geological carbon in the leaves and stems of some riparian plants near streams that receive inputs of regional groundwater. Also, discharge of regional groundwater is responsible for input of dissolved organic matter with distinctive chemistry to rainforest streams and wetlands. The discharge of regional groundwater in lowland surface waters has a major impact on the carbon cycle in this and likely other tropical and non-tropical forests.

  19. Modeling Water and Nutrient Transport through the Soil-Root-Canopy Continuum: Explicitly Linking the Below- and Above-Ground Processes

    Science.gov (United States)

    Kumar, P.; Quijano, J. C.; Drewry, D.

    2010-12-01

    Vegetation roots provide a fundamental link between the below ground water and nutrient dynamics and above ground canopy processes such as photosynthesis, evapotranspiration and energy balance. The “hydraulic architecture” of roots, consisting of the structural organization of the root system and the flow properties of the conduits (xylem) as well as interfaces with the soil and the above ground canopy, affect stomatal conductance thereby directly linking them to the transpiration. Roots serve as preferential pathways for the movement of moisture from wet to dry soil layers during the night, both from upper soil layer to deeper layers during the wet season (‘hydraulic descent’) and vice-versa (‘hydraulic lift’) as determined by the moisture gradients. The conductivities of transport through the root system are significantly, often orders of magnitude, larger than that of the surrounding soil resulting in movement of soil-moisture at rates that are substantially larger than that through the soil. This phenomenon is called hydraulic redistribution (HR). The ability of the deep-rooted vegetation to “bank” the water through hydraulic descent during wet periods for utilization during dry periods provides them with a competitive advantage. However, during periods of hydraulic lift these deep-rooted trees may facilitate the growth of understory vegetation where the understory scavenges the hydraulically lifted soil water. In other words, understory vegetation with relatively shallow root systems have access to the banked deep-water reservoir. These inter-dependent root systems have a significant influence on water cycle and ecosystem productivity. HR induced available moisture may support rhizosphere microbial and mycorrhizal fungi activities and enable utilization of heterogeneously distributed water and nutrient resources To capture this complex inter-dependent nutrient and water transport through the soil-root-canopy continuum we present modeling

  20. Linking benthic hydrodynamics and cold-water coral occurrences: A high-resolution model study at three cold-water coral provinces in the NE Atlantic

    Science.gov (United States)

    Mohn, Christian; Rengstorf, Anna; White, Martin; Duineveld, Gerard; Mienis, Furu; Soetaert, Karline; Grehan, Anthony

    2014-03-01

    Observations from numerous cold-water coral locations in the NE Atlantic show energetic near-bottom flow dynamics along the European continental margin at individual coral mounds and mound clusters. Dynamics are largely controlled by tide-topography interaction generating and enhancing periodic motions such as trapped waves, freely propagating internal tides and internal hydraulic jumps. In this study, linkages between key abiotic parameters and cold water coral occurrences are explored across entire cold-water coral mound provinces using an integrated modelling and observational approach. The 3-D ocean circulation model ROMS-AGRIF was applied to simulate near-bottom hydrodynamic conditions at three provinces in the NE Atlantic (Logachev mounds, Arc mounds and Belgica mounds) adopting a nested model setup with a central grid resolution of 250 m. Simulations were carried out with a focus on accurate high-resolution topography and tidal forcing. The central model bathymetry was taken from high-resolution INSS (Irish National Seabed Survey) seafloor mapping data. The model was integrated over a full one-year reference period starting from the 1st January 2010. Interannual variability was not considered. Tidal forcing was obtained from a global solution of the Oregon State University (OSU) inverse tidal model. Modelled fields of benthic currents were validated against available independent in situ observations. Coral assemblage patterns (presence and absence locations) were obtained from benthic surveys of the EU FP7 CoralFISH programme and supplemented by data from additional field surveys. Modelled near-bottom currents, temperature and salinity were analysed for a 1-month subset (15th April to 15th May 2010) corresponding to the main CoralFISH survey period. The model results show intensified near-bottom currents in areas where living corals are observed by contrast with coral absence and random background locations. Instantaneous and time-mean current speeds at

  1. Rift systems of the Russian Eastern Arctic shelf and Arctic deep water basins: link between geological history and geodynamics

    Directory of Open Access Journals (Sweden)

    A. M. Nikishin

    2017-01-01

    Full Text Available In our study, we have developed a new tectonic scheme of the Arctic Ocean, which is based mainly on seismic profiles obtained in the Arctic-2011, Arctic-2012 and Arctic-2014 Projects implemented in Russia. Having interpreted many seismic profiles, we propose a new seismic stratigraphy of the Arctic Ocean. Our main conclusions are drawn from the interpretation of the seismic profiles and the analysis of the regional geological data. The results of our study show that rift systems within the Laptev, the East Siberian and the Chukchi Seas were formed not earlier than Aptian. The geological structure of the Eurasian, Podvodnikov, Toll and Makarov Basins is described in this paper. Having synthesized all the available data on the study area, we propose the following model of the geological history of the Arctic Ocean: 1. The Canada Basin formed till the Aptian (probably, during Hauterivian-Barremian time. 2. During the Aptian-Albian, large-scale tectonic and magmatic events took place, including plume magmatism in the area of the De Long Islands, Mendeleev Ridge and other regions. Continental rifting started after the completion of the Verkhoyansk-Chukotka orogenу, and rifting occurred on the shelf of the Laptev, East Siberian, North Chukchi and South Chukchi basins, and the Chukchi Plateau; simultaneously, continental rifting started in the Podvodnikov and Toll basins. 3. Perhaps the Late Cretaceous rifting continued in the Podvodnikov and Toll basins. 4. At the end of the Late Cretaceous and Paleocene, the Makarov basin was formed by rifting, although local spreading of oceanic crust during its formation cannot be excluded. 5. The Eurasian Basin started to open in the Early Eocene. We, of course, accept that our model of the geological history of the Arctic Ocean, being preliminary and debatable, may need further refining. In this paper, we have shown a link between the continental rift systems on the shelf and the formation history of the Arctic

  2. Removal of some organic pollutants in water employing ceramic membranes impregnated with cross-linked silylated dendritic and cyclodextrin polymers.

    Science.gov (United States)

    Allabashi, Roza; Arkas, Michael; Hörmann, Gerold; Tsiourvas, Dimitris

    2007-01-01

    Triethoxysilylated derivatives of poly(propylene imine) dendrimer, polyethylene imine and polyglycerol hyperbranched polymers and beta-cyclodextrin have been synthesized and characterized. These compounds impregnated ceramic membranes made from Al(2)O(3), SiC and TiO(2) and subsequently sol-gel reaction led to their polymerization and chemical bond formation with the ceramic substrates. The resulting organic-inorganic filters were tested for the removal of a variety of organic pollutants from water. They were found to remove of polycyclic aromatic hydrocarbons (up to 99%), of monocyclic aromatic hydrocarbons (up to 93%), trihalogen methanes (up to 81%), pesticides (up to 43%) and methyl-tert-butyl ether (up to 46%).

  3. A novel water-based process produces eco-friendly bio-adhesive made from green cross-linked soybean soluble polysaccharide and soy protein.

    Science.gov (United States)

    Yuan, Cheng; Chen, Mingsong; Luo, Jing; Li, Xiaona; Gao, Qiang; Li, Jianzhang

    2017-08-01

    In this study, an eco-friendly soy protein adhesive was developed that utilized two components from soybean meal without addition of any toxic material. A plant-based, water-soluble and inexpensive soybean soluble polysaccharide was used as the novel renewable material to combine with soy protein to produce a soy protein adhesive. Three-plywood was fabricated with the resulting adhesive, and its wet shear strength was measured. The results showed the wet shear strength of plywood bonded by the adhesive reached 0.99MPa, meeting the water resistance requirement for interior use panels. This improvement was attributed to the following reasons: (1) Combination of cross-linked soybean soluble polysaccharide and soy protein formed an interpenetrating network structure, improving the thermal stability and water resistance of the cured adhesive. (2) Adding CL-SSPS decreased the adhesive viscosity to 15.14Pas, which increased the amount of the adhesive that penetrate the wood's surface and formed more interlocks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Tropical Ocean Evaporation/SST Sensitivity and It's Link to Water and Energy Budget Variations During ENSO

    Science.gov (United States)

    Robertson, Franklin R.; Marshall, Susan; Oglesby, Robert; Roads, John; Sohn, Byung-Ju; Arnold, James E. (Technical Monitor)

    2001-01-01

    The continuing debate over feedback mechanisms governing tropical sea surface temperatures (SSTs) and tropical climate in general has highlighted the diversity of potential checks and balances within the climate system. Competing feedbacks due to changes in surface evaporation, water vapor, and cloud long- and shortwave radiative properties each may serve critical roles in stabilizing or destabilizing the climate system. It is also intriguing that even those climate variations having origins internal to the climate system - changes in ocean heat transport for example, apparently require complementary equilibrating effects by changes in atmospheric energy fluxes. Perhaps the best observational evidence of this is the relatively invariant nature of tropically averaged net radiation exiting the top-of-atmosphere (TOA) as measured by broadband satellite sensors over the past two decades. Thus, analyzing how these feedback mechanisms are operating within the context of current interannual variability may offer considerable insight for anticipating future climate change. In this paper we focus primarily on interannual variations of ocean evaporative fluxes and their significance for coupled water and energy cycles within the tropical climate system. In particular, we use both the da Silva estimates of surface fluxes (based on the Comprehensive Ocean Atmosphere Data Set, COADS) and numerical simulations from several global climate models to examine evaporation sensitivity to perturbations in SST associated with warm and cold ENSO events. The specific questions we address are as follows: (1) What recurring patterns of surface wind and humidity anomalies are present during ENSO and how do they combine to yield systematic evaporation anomalies?, (2) What is the resulting tropical ocean mean evaporation-SST sensitivity associated with this climate perturbation?, and (3) What role does this evaporation play in tropical heat and water balance over tropical oceanic regions? We

  5. A Reconsideration of the Link between the Energetics of Water and of ATP Hydrolysis Energy in the Power Strokes of Molecular Motors in Protein Structures

    Directory of Open Access Journals (Sweden)

    Wilfred F. Widdas

    2008-09-01

    Full Text Available Mechanical energy from oxygen metabolism by mammalian tissues has been studied since 1837. The production of heat by mechanical work was studied by Fick in about 1860. Prior to Fick’s work, energetics were revised by Joule’s experiments which founded the First Law of Thermodynamics. Fenn in 1923/24 found that frog muscle contractions generated extra heat proportional to the amount of work done in shortening the muscle. This was fully consistent with the Joule, Helmholtz concept used for the First Law of Thermodynamics. The link between the energetics of water and ATP hydrolysis in molecular motors is recommended for reconsideration.

  6. Water resource protection in Australia: Links between land use and river health with a focus on stubble farming systems

    Science.gov (United States)

    Bowmer, Kathleen H.

    2011-06-01

    SummaryStubble farming (conservation farming, minimum tillage, zero tillage) has increased in Australia over several decades with claims of improved productivity, landscape stability and environmental benefit including ecosystem services downstream, yet recent audits show a dramatic and general decline in river health. This review explores explanations for this apparent anomaly. Many confounding factors complicate interactions between land use and river condition and may disguise or over-ride the potential benefits of adoption of stubble systems or other improvements in agricultural land use practice. These factors include climate change and variability; land use changes including an increase in bushfires, growth of farm dams and afforestation; lag times between land use change and expression of benefits in river systems; use of inappropriate scale that disguises local benefit; variations in the extent of ecosystem resilience; impacts of river regulation; and impacts of introduced species. Additionally, the value of river condition and utility is complicated by different local or regional perceptions and by contrasting rural and urban outlooks. The use of indicators, risk frameworks and biophysical modelling may help elucidate the complex relationships between land use and downstream ecosystem impact. The strengthening of local, regional and catchment scale approaches is advocated. This includes the re-integration of land management and governance with water management and planning. It is encouraging that farmers are themselves developing systems to optimise trade-offs between on-farm activities and ecosystem service benefits. This approach needs to be supported and extended.

  7. Linking Environmental Research and Practice: Lessons From The Integration of Climate Science and Water Management in the Western United States

    Science.gov (United States)

    Ferguson, D. B.; Rice, J.; Woodhouse, C. A.

    2015-12-01

    Efforts to better connect scientific research with people and organizations involved in environmental decision making are receiving increased interest and attention. Some of the challenges we currently face, however—including complex questions associated with climate change—present unique challenges because of their scale and scope. Focused research on the intersections between environment and society has provided substantial insight into dynamics of large-scale environmental change and the related impacts on people, natural resources, and ecosystems, yet our ability to connect this research to real-world decision making remains limited. Addressing these complex environmental problems requires broad cooperation between scientists and those who may apply research results in decision making, but there are few templates for guiding the growing number of scientists and practitioners now engaging in this kind of cooperative work. This presentation will offer a set of heuristics for carrying out collaborative work between scientists and practitioners. These heuristics were derived from research that examined the direct experiences of water resources professionals and climate researchers who have been working to integrate science and practice.

  8. Novel Insights Linking Ecological Health to Biogeochemical Hotspots across the Groundwater-Surface Water Interface in Mixed Land Use Stream Systems

    Science.gov (United States)

    McKnight, U. S.; Sonne, A. T.; Rasmussen, J. J.; Rønde, V.; Traunspurger, W.; Höss, S.; Bjerg, P. L.

    2017-12-01

    Increasing modifications in land use and water management have resulted in multiple stressors impacting freshwater ecosystems globally. Chemicals with the potential to impact aquatic habitats are still often evaluated individually for their adverse effects on ecosystem health. This may lead to critical underestimations of the combined impact caused by interactions occurring between stressors not typically evaluated together, e.g. xenobiotic groundwater pollutants and trace metals. To address this issue, we identified sources and levels of chemical stressors along a 16-km groundwater-fed stream corridor (Grindsted, Denmark), representative for a mixed land use stream system. Potential pollution sources included two contaminated sites (factory, landfill), aquaculture, wastewater/industrial discharges, and diffuse sources from agriculture and urban areas. Ecological status was determined by monitoring meiobenthic and macrobenthic invertebrate communities.The stream was substantially impaired by both geogenic and anthropogenic sources of metals throughout the investigated corridor, with concentrations close to or above threshold values for barium, copper, lead, nickel and zinc in the stream water, hyporheic zone and streambed sediment. The groundwater plume from the factory site caused elevated concentrations of chlorinated ethenes, benzene and pharmaceuticals in both the hyporheic zone and stream, persisting for several km downstream. Impaired ecological conditions, represented by a lower abundance of meiobenthic individuals, were found in zones where the groundwater plume discharges to the stream. The effect was only pronounced in areas characterized by high xenobiotic organic concentrations and elevated dissolved iron and arsenic levels - linked to the dissolution of iron hydroxides caused by the degradation of xenobiotic compounds in the plume. The results thus provide ecological evidence for the interaction of organic and inorganic chemical stressors, which may

  9. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  10. Why Seedlings Die: Linking Carbon and Water Limitations to Mechanisms of Mortality During Establishment in Conifer Seedlings

    Science.gov (United States)

    Reinhardt, K.; Germino, M. J.; Kueppers, L. M.; Mitton, J.; Castanha, C.

    2012-12-01

    /or reduced hydraulic conductance), associated with roots unable to escape the seasonal drying front in the soil, would limit seedling survival at least as much as C-balance dysfunction; and 3) seedling mortality would not be due to exhaustion of whole-plant NSC, as suggested by appreciable NSC in dead conifer seedlings reported in alpine treeline studies. RESULTS AND INTERPRETATIONS Preliminary results suggest that photosynthesis, fluorescence, and whole-tree NSC remained high until mortality, when plant water potentials decreased below -5 MPa. As seedlings approached mortality, NSC concentrations (both soluble sugars and starch) in roots decreased from ~9% to physiology, or exhaustion of NSC at the whole-plant level. We propose that hydraulic failure was likely the proximate cause of mortality under the conditions we evaluated, and drought-induced inhibition of NSC transport to roots may ultimately undermine the ability of seedlings to tap progressively deeper water sources during summer drying.

  11. Tracking Water, C, N, and P by Linking Local Scale Soil Hydrologic and Biogeochemical Features to Watershed Scale

    Science.gov (United States)

    Sedaghatdoost, A.; Mohanty, B.; Huang, Y.

    2017-12-01

    The biogeochemical cycles of carbon (C), nitrogen (N), and phosphorus (P) have many contemporary significance due to their critical roles in determining the structure and function of ecosystems. The objectives of our study is to find out temporal dynamics and spatial distribution of soil physical, chemical, and biological properties and their interaction with C, N, and P cycles in the soil for different land covers and weather conditions. The study is being conducted at three locations within Texas Water Observatory (TWO), including Riesel (USDA-ARS experimental watersheds), Texas A&M Agrilife Research Farm, and Danciger forest in Texas. Soil physical, hydraulic, chemical (total C, total N, total P, pH, EC, redox potential, N-NO3-, N-NH4+, PO42-, K, Ca, Mg, Na, Mn, and Alox and Feox), and microbiological (Microbial biomass C, N, and P, PLFA analysis, enzymatic activity) properties are being measured in the top 30 cm of the soil profile. Our preliminary data shows that biogeochemical processes would be more profound in the areas with higher temperature and precipitation as these factors stimulate microbial activity and thus influence C, N, and P cycles. Also concentrations of C and N are greater in woodlands relative to remnant grasslands as a consequence of the greater above- and below-ground productivity of woodlands relative to remnant grasslands. We hypothesize that finer soil textures have more organic matter, microbial population, and reactive surfaces for chemicals than coarse soils, as described in some recent literature. However, the microbial activity may not be active in fine textured soils as organic materials may be sorbed to clay surfaces or protected from decomposing organisms. We also expect reduced condition in saturated soils which will decrease carbon mineralization while increase denitrification and alkalinity in the soil. Spatio-temporal data with initial evaluation of biogeochemical factors/processes for different land covers will be presented.

  12. Radiating gap filler

    International Nuclear Information System (INIS)

    2009-01-01

    Full text: In May, corrosion on the outside wall of the over 50 year old Canadian Chalk River reactor vessel caused a heavy water leak and the reactor was shut down triggering worldwide a nuclear medicine shortage. The reactor is also a major supplier of the isotope molybdenum-99 (Mo-99), a precursor of the medically widely used technetium-99 m . To fill the gap in demand, the Australian Nuclear Science and Technology Organisation has now arranged with US company Lantheus Medical Imaging, Inc., a world leader in medical imaging, to supply Mo-99. Subject to pending Australian regulatory processes, the deal is expected to assist in alleviating the world's current nuclear medicine shortage. As ANSTO is currently also the only global commercial supplier that produces Mo-99 from low enriched uranium (LEU) targets, Lantheus will be the first company bringing LEU derived Tc-99 m to the US market. To date, over 95% of Mo-99 is derived from highly enriched uranium (HEU) targets. However, there are concerns regarding proliferation risks associated with HEU targets and for commercial uses production from LEU targets would be desirable. ANSTO says that global Mo-99 supply chain is fragile and limited and it is working closely with nuclear safety and healthy regulators, both domestically and overseas, to expedite all necessary approvals to allow long-term production and export of medical isotopes.

  13. Gap and density theorems

    CERN Document Server

    Levinson, N

    1940-01-01

    A typical gap theorem of the type discussed in the book deals with a set of exponential functions { \\{e^{{{i\\lambda}_n} x}\\} } on an interval of the real line and explores the conditions under which this set generates the entire L_2 space on this interval. A typical gap theorem deals with functions f on the real line such that many Fourier coefficients of f vanish. The main goal of this book is to investigate relations between density and gap theorems and to study various cases where these theorems hold. The author also shows that density- and gap-type theorems are related to various propertie

  14. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  15. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger

    2012-01-01

    educational goals, learning content, or value clarification. Health pedagogy is often a matter of retrospective rationalization rather than the starting point of planning. Health and risk behaviour approaches override health educational approaches. Conclusions: Operational links between health education......, health professionalism, and management strategies pose the foremost challenge. Operational links indicates cooperative levels that facilitate a creative and innovative effort across traditional professional boundaries. It is proposed that such links are supported by network structures, shared semantics...

  16. Is reliable water access the solution to undernutrition? A review of the potential of irrigation to solve nutrition and gender gaps in Africa South of the Sahara:

    OpenAIRE

    Domènech, Laia

    2015-01-01

    Interventions aimed at increasing water availability for livelihood and domestic activities have great potential to improve various determinants of undernutrition, such as the quantity and diversity of foods consumed within the household, income generation, and women’s empowerment. However, current evidence on the topic is diluted across many different publications. This paper aims to connect the dots and review the literature available on the linkages between irrigation and food security, im...

  17. Measurement of bubble velocity in an air/water flow through a narrow gap by using high-speed cinematography; Ermittlung der Blasengeschwindigkeit einer Luft/Wasser-Spaltstroemung mit Hilfe der Hochgeschwindigkeitskinematographie

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, S.; Friedel, L. [Technische Univ. Hamburg-Harburg, Hamburg (Germany)

    1997-12-01

    To predict the mass flow of a two phase mixture at a given pressure difference through narrow gaps, apart from the change in state of the gas phase during pressure reduction, the knowledge of the fluid dynamics on balance which occurs in the form of a relative velocity between the phases is important. These two influences were examined with the aid of high speed cinematography for a water/air bubble flow. Apart from the quick reduction in pressure due to the sudden reduction in crossection at the entry to the gap, there are no significant differences between the experimentally determined volume change in bubbles of different sizes and that calculated assuming an isothermal change in state. The mean velocity of the bubbles does not differ appreciably from that calculated assuming an homogeneous flow. [Deutsch] Zur Vorhersage des sich bei gegebener Druckdifferenz einstellenden Massenstroms eines Zweiphasengemischs durch enge Spalte ist neben der Zustandsaenderung der Gasphase waehrend der Druckabsenkung u.a. auch die Kenntnis des sich dabei einstellenden fluiddynamischen Ungleichgewichts in Form einer Relativgeschwindigkeit zwischen den Phasen von Bedeutung. Diese beiden Einfluesse wurden mit Hilfe der Hochgeschwindigkeitskinematographie fuer eine Wasser/Luft-Blasenstroemung untersucht. Abgesehen von der raschen Druckabsenkung aufgrund der ploetzlichen Querschnittsverengung im Spalteintritt treten keine nennenswerten Unterschiede zwischen den experimentell ermittelten und den unter der Annahme einer isothermen Zustandsaenderungen berechneten Volumenaenderung verschiedengrosser Blasen auf. Die mittlere Geschwindigkeit der Blasen unterscheidet sich dabei nicht wesentlich von der unter der Annahme einer homogenen Stroemung berechneten. (orig.)

  18. Measurement of bubble velocity in an air/water flow through a narrow gap by using high-speed cinematography; Ermittlung der Blasengeschwindigkeit einer Luft/Wasser-Spaltstroemung mit Hilfe der Hochgeschwindigkeitskinematographie

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, S.; Friedel, L. [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Arbeitsbereich Stroemungsmechanik

    1998-05-01

    For the prediction of the establishing two-phase massflow for a given pressure difference across a narrow rectangular gap, beside others, the knowledge of the change of state of the gas phase and the fluiddynamic non-equilibrium in form of the slip velocity between the phases is needed. For an air/water bubbly flow it turned out by using high-speed cinematography that apart from the quick pressure decrease during the rapid acceleration at the gap inlet no significant difference between the measured and the predicted bubble size changes assuming an isothermal change of state of the air bubbles could be detected. The measured mean bubble velocities do not considerably deviate from the values calculated on the basis of a homogeneous flow. (orig.) [Deutsch] Zur Vorhersage des sich bei gegebener Druckdifferenz einstellenden Massenstroms eines Zweiphasengemischs durch enge Spalte ist neben der Zustandsaenderung der Gasphase waehrend der Druckabsenkung u.a. auch die Kenntnis des sich dabei einstellenden fluiddynamischen Ungleichgewichts in Form einer Relativgeschwindigkeit zwischen den Phasen von Bedeutung. Diese beiden Einfluesse wurden mit Hilfe der Hochgeschwindigkeitskinematographie fuer eine Wasser/Luft-Blasenstroemung untersucht. Abgesehen von der raschen Druckabsenkung aufgrund der ploetzlichen Querschnittsverengung im Spalteintritt treten keine nennenswerten Unterschiede zwischen den experimentell ermittelten und den unter der Annahme einer isothermen Zustandsaenderungen berechneten Volumenaenderung verschiedengrosser Blasen auf. Die mittlere Geschwindigkeit der Blasen unterscheidet sich dabei nicht wesentlich von der unter der Annahme einer homogenen Stroemung berechneten. (orig.)

  19. Bridge the Gap

    DEFF Research Database (Denmark)

    Marselis, Randi

    2017-01-01

    This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

  20. Bridging a Cultural Gap

    Science.gov (United States)

    Leviatan, Talma

    2008-01-01

    There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes--aimed at bridging the gap between high-school mathematics and tertiary mathematics--is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a…

  1. Understanding the Gender Gap.

    Science.gov (United States)

    Goldin, Claudia

    1985-01-01

    Despite the great influx of women into the labor market, the gap between men's and women's wages has remained stable at 40 percent since 1950. Analysis of labor data suggests that this has occurred because women's educational attainment compared to men has declined. Recently, however, the wage gap has begun to narrow, and this will probably become…

  2. Bridging the Transition Gap

    Science.gov (United States)

    2013-05-23

    period and provide recommendations to guide future research and policy development. 4 DEFINING THE TRANSITIONAL SECURITY GAP There have been...BRIDGING THE TRANSITION GAP A Monograph by MAJ J.D. Hansen United States Army School of Advanced Military Studies United States Army...suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704

  3. Spatial-temporal evolution of self-organized loop-patterns on a water surface and a diffuse discharge in the gap

    Science.gov (United States)

    Li, Xuechen; Geng, Jinling; Jia, Pengying; Zhang, Panpan; Zhang, Qi; Li, Yaru

    2017-11-01

    Excited by an alternating current voltage, a patterned discharge and a diffuse discharge are generated in a needle to liquid configuration. Using an intensified charge-coupled device (ICCD), temporal evolution of the discharge between the two electrodes is investigated for the diffuse mode and the patterned mode, respectively. For the diffuse mode, the positive discharge is in a glow regime, and the negative discharge is in a Townsend discharge regime. For the patterned mode, the discharge always belongs to the Townsend discharge regime. Moreover, in the patterned mode, various patterns including the single loop, single loop with the surrounding corona, triple loops, and concentric loops with a central spot are observed on the water surface with the increasing positive peak-value of the applied voltage (Upp). Temporally resolved images of the loop-patterns are captured on the water surface. From the electrical measurements and the ICCD imaging, it is found that the loop pattern emerges after the discharge bridges the two electrodes. Then, it begins to evolve and finally degenerates with the decrease in the discharge current. The pattern does not disappear until the discharge quenches. Formation of the loop-patterns is attributed to the role of negative ions.

  4. Links between circulation indices and precipitation in the Mediterranean in an ensemble of regional climate models

    Czech Academy of Sciences Publication Activity Database

    Beranová, Romana; Kyselý, Jan

    2016-01-01

    Roč. 123, č. 3 (2016), s. 693-701 ISSN 0177-798X R&D Projects: GA ČR GAP209/10/2265 EU Projects: European Commission(XE) 505539 - ENSEMBLES Program:FP6 Institutional support: RVO:68378289 Keywords : atmospheric sciences climatology * atmospheric protection * air quality control * air pollution * waste water technology * water pollution control * water management * aquatic pollution Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.640, year: 2016 http://link.springer.com/article/10.1007%2Fs00704-015-1381-6

  5. An ecohydrological sketch of climate change impacts on water and natural ecosystems for the Netherlands: bridging the gap between science and society

    Directory of Open Access Journals (Sweden)

    J. P. M. Witte

    2012-11-01

    Full Text Available For policy making and spatial planning, information is needed about the impacts of climate change on natural ecosystems. To provide this information, commonly hydrological and ecological models are used. We give arguments for our assessment that modelling only is insufficient for determining the impacts of climate changes on natural ecosystems at regional scales. Instead, we proposed a combination of hydrological simulations, a literature review and process-knowledge on climate-hydrology-vegetation interactions, to compile a sketch map that indicates climate change effects on a number of ecosystems in the Netherlands. Soon after a first version of our sketch map was published by a Dutch professional journal, copies appeared in policy documents, and also in a commercial and popular atlas of the Netherlands. Moreover, the map led to a question in the Dutch parliament about the sustainability of bog reserves under the future climate. Apparently, there was an urgent need for the information provided by the map.

    The map shows that climate change will presumably have the largest influence on ecosystems in the Netherlands that depend on precipitation as the major water source, like heathlands, dry grasslands, rain-fed moorland pools and raised bogs. Also highly susceptible are fens in reserves surrounded by deeply drained polders, because such fens depend on the inlet of surface water, of which quality is likely to deteriorate upon climate change. While the map is indicative for directions of change, in view of the uncertainties of our study, no conclusions should be drawn that may have far-reaching consequences, such as giving up certain nature targets that might no longer be feasible in the future climate. Instead, we advise to anticipate the potential threats from climate change by taking a number of adaptation measures that enhance the robustness of nature reserves.

    To improve climate change projections on hydrology and ecosystems

  6. An ecohydrological sketch of climate change impacts on water and natural ecosystems for the Netherlands: bridging the gap between science and society

    Science.gov (United States)

    Witte, J. P. M.; Runhaar, J.; van Ek, R.; van der Hoek, D. C. J.; Bartholomeus, R. P.; Batelaan, O.; van Bodegom, P. M.; Wassen, M. J.; van der Zee, S. E. A. T. M.

    2012-11-01

    For policy making and spatial planning, information is needed about the impacts of climate change on natural ecosystems. To provide this information, commonly hydrological and ecological models are used. We give arguments for our assessment that modelling only is insufficient for determining the impacts of climate changes on natural ecosystems at regional scales. Instead, we proposed a combination of hydrological simulations, a literature review and process-knowledge on climate-hydrology-vegetation interactions, to compile a sketch map that indicates climate change effects on a number of ecosystems in the Netherlands. Soon after a first version of our sketch map was published by a Dutch professional journal, copies appeared in policy documents, and also in a commercial and popular atlas of the Netherlands. Moreover, the map led to a question in the Dutch parliament about the sustainability of bog reserves under the future climate. Apparently, there was an urgent need for the information provided by the map. The map shows that climate change will presumably have the largest influence on ecosystems in the Netherlands that depend on precipitation as the major water source, like heathlands, dry grasslands, rain-fed moorland pools and raised bogs. Also highly susceptible are fens in reserves surrounded by deeply drained polders, because such fens depend on the inlet of surface water, of which quality is likely to deteriorate upon climate change. While the map is indicative for directions of change, in view of the uncertainties of our study, no conclusions should be drawn that may have far-reaching consequences, such as giving up certain nature targets that might no longer be feasible in the future climate. Instead, we advise to anticipate the potential threats from climate change by taking a number of adaptation measures that enhance the robustness of nature reserves. To improve climate change projections on hydrology and ecosystems, future research should especially

  7. 'Mind the Gap!'

    DEFF Research Database (Denmark)

    Persson, Karl Gunnar

    This paper challenges the widely held view that sharply falling real transport costs closed the transatlantic gap in grain prices in the second half of the 19th century. Several new results emerge from an analysis of a new data set of weekly wheat prices and freight costs from New York to UK...... markets. Firstly, there was a decline in the transatlantic price gap but it was not sharp and the gap remained substantial. Secondly, the fall in the transatlantic price differential had more to do with improved market and marketing efficiency than with falling transport costs. Thirdly, spurious price...

  8. Use of Heavy Water (D2O in Developing Thermostable Recombinant p26 Protein Based Enzyme-Linked Immunosorbent Assay for Serodiagnosis of Equine Infectious Anemia Virus Infection

    Directory of Open Access Journals (Sweden)

    Harisankar Singha

    2014-01-01

    Full Text Available Thermostabilizing effect of heavy water (D2O or deuterium oxide has been demonstrated previously on several enzymes and vaccines like oral poliovirus vaccine and influenza virus vaccine. In view of the above observations, effect of heavy water on in situ thermostabilization of recombinant p26 protein on enzyme-linked immunosorbent assay (ELISA for serodiagnosis of equine infectious anemia virus (EIAV infection was investigated in the present study. The carbonate-bicarbonate coating buffer was prepared in 60% and 80% D2O for coating the p26 protein in 96-well ELISA plate and thermal stability was examined at 4°C, 37°C, 42°C, and 45°C over a storage time from 2 weeks to 10 months. A set of positive serum (n=12 consisting of strong, medium, and weak titer strength (4 samples in each category and negative serum (n=30 were assessed in ELISA during the study period. At each time point, ELISA results were compared with fresh plate to assess thermal protective effect of D2O. Gradual increase in the stabilizing effect of 80% D2O at elevated temperature (37°C < 42°C < 45°C was observed. The 80% D2O provides the thermal protection to rp26 protein in ELISA plate up to 2 months of incubation at 45°C. The findings of the present study have the future implication of adopting cost effective strategies for generating more heat tolerable ELISA reagents with extended shelf life.

  9. Milk progesterone enzyme-linked immunosorbent assay as a tool to investigate ovarian cyclicity of water buffaloes in relation to body condition score and milk production

    Directory of Open Access Journals (Sweden)

    Banu Turgish A

    2012-05-01

    Full Text Available Abstract Background Application of assisted reproductive technologies in buffaloes is limited to some extent by farmers’ inability to detect oestrus because of its poor expression. The present study aimed at investigating reliability of a milk progesterone enzyme-linked immunosorbent assay (ELISA to assess the ovarian cyclicity during post partum, oestrus and post-breeding periods in water buffaloes. Methods Progesterone concentrations were measured by an ELISA in milk of 23 postpartum buffaloes in relation to oestrus, pregnancy, body condition score (BCS and milk production. Two milk samples were taken at 10 days intervals, every month starting from day 30 and continued to day 150 post partum. BCS and milk production were recorded during sample collection. Milk samples from bred buffaloes were collected at Day 0 (day of breeding, Days 10–12 and Days 22–24. Defatted milk was preserved at −80°C until analysis. Pregnancy was confirmed by palpation per rectum on Days 70–90. Results Seventeen buffaloes had 47 ovulatory cycles, one to four in each, 13 were detected in oestrus once (28 % oestrus detection rate. Progesterone concentration ≥1 ng/ml in one of the two 10-day-interval milk samples reflected ovulation and corpus luteum formation. The intervals between calving to first luteal activity and to first detected oestrus varied from 41 to 123 days (n = 17 and 83 to 135 (n = 13 days, respectively. Eight buffaloes were bred in the course of the study and seven were found pregnant. These buffaloes had a progesterone profile of low (P P  Conclusions Milk progesterone ELISA is a reliable tool for monitoring ovarian cyclicity and good BCS may be an indicator of resuming cyclicity in water buffalo.

  10. Milk progesterone enzyme-linked immunosorbent assay as a tool to investigate ovarian cyclicity of water buffaloes in relation to body condition score and milk production.

    Science.gov (United States)

    Banu, Turgish A; Shamsuddin, Mohammed; Bhattacharjee, Jayonta; Islam, Mohammad F; Khan, Saiful I; Ahmed, Jalal U

    2012-05-03

    Application of assisted reproductive technologies in buffaloes is limited to some extent by farmers' inability to detect oestrus because of its poor expression. The present study aimed at investigating reliability of a milk progesterone enzyme-linked immunosorbent assay (ELISA) to assess the ovarian cyclicity during post partum, oestrus and post-breeding periods in water buffaloes. Progesterone concentrations were measured by an ELISA in milk of 23 postpartum buffaloes in relation to oestrus, pregnancy, body condition score (BCS) and milk production. Two milk samples were taken at 10 days intervals, every month starting from day 30 and continued to day 150 post partum. BCS and milk production were recorded during sample collection. Milk samples from bred buffaloes were collected at Day 0 (day of breeding), Days 10-12 and Days 22-24. Defatted milk was preserved at -80°C until analysis. Pregnancy was confirmed by palpation per rectum on Days 70-90. Seventeen buffaloes had 47 ovulatory cycles, one to four in each, 13 were detected in oestrus once (28 % oestrus detection rate). Progesterone concentration ≥1 ng/ml in one of the two 10-day-interval milk samples reflected ovulation and corpus luteum formation. The intervals between calving to first luteal activity and to first detected oestrus varied from 41 to 123 days (n = 17) and 83 to 135 (n = 13) days, respectively. Eight buffaloes were bred in the course of the study and seven were found pregnant. These buffaloes had a progesterone profile of low (progesterone ELISA is a reliable tool for monitoring ovarian cyclicity and good BCS may be an indicator of resuming cyclicity in water buffalo.

  11. Disruption of hippocampus-regulated behavioural and cognitive processes by heterozygous constitutive deletion of SynGAP.

    Science.gov (United States)

    Muhia, Mary; Yee, Benjamin K; Feldon, Joram; Markopoulos, Foivos; Knuesel, Irene

    2010-02-01

    The brain-specific Ras/Rap-GTPase activating protein (SynGAP) is a prime candidate linking N-methyl-d-aspartate receptors to the regulation of the ERK/MAP kinase signalling cascade, suggested to be essential for experience-dependent synaptic plasticity. Here, we evaluated the behavioural phenotype of SynGAP heterozygous knockout mice (SG(+/-)), expressing roughly half the normal levels of SynGAP. In the cognitive domain, SG(+/-) mice demonstrated severe working and reference memory deficits in the radial arm maze task, a mild impairment early in the transfer test of the water maze task, and a deficiency in spontaneous alternation in an elevated T-maze. In the non-cognitive domain, SG(+/-) mice were hyperactive in the open field and appeared less anxious in the elevated plus maze test. In contrast, object recognition memory performance was not impaired in SG(+/-) mice. The reduction in SynGAP thus resulted in multiple behavioural traits suggestive of aberrant cognitive and non-cognitive processes normally mediated by the hippocampus. Immunohistochemical evaluation further revealed a significant reduction in calbindin-positive interneurons in the hippocampus and doublecortin-positive neurons in the dentate gyrus of adult SG(+/-) mice. Heterozygous constitutive deletion of SynGAP is therefore associated with notable behavioural as well as morphological phenotypes indicative of hippocampal dysfunction. Any suggestion of a possible causal link between them however remains a matter for further investigation.

  12. CIEEM Skills Gap Project

    OpenAIRE

    Bartlett, Deborah

    2017-01-01

    This paper describes the research conducted for the Chartered Institute for Ecology and Environmental Management to identify skills gaps within the profession. It involved surveys of professionals, conference workshops and an investigation into the views of employers regarding graduate recruitment.

  13. Wide-Gap Chalcopyrites

    CERN Document Server

    Siebentritt, Susanne

    2006-01-01

    Chalcopyrites, in particular those with a wide band gap, are fascinating materials in terms of their technological potential in the next generation of thin-film solar cells and in terms of their basic material properties. They exhibit uniquely low defect formation energies, leading to unusual doping and phase behavior and to extremely benign grain boundaries. This book collects articles on a number of those basic material properties of wide-gap chalcopyrites, comparing them to their low-gap cousins. They explore the doping of the materials, the electronic structure and the transport through interfaces and grain boundaries, the formation of the electric field in a solar cell, the mechanisms and suppression of recombination, the role of inhomogeneities, and the technological role of wide-gap chalcopyrites.

  14. Identification of new SSR markers linked to leaf chlorophyll content, flag leaf senescence and cell membrane stability traits in wheat under water stressed condition.

    Science.gov (United States)

    Barakat, Mohamed N; Saleh, Mohamed; Al-Doss, Abdullah A; Moustafa, Khaled A; Elshafei, Adel A; Al-Qurainy, Fahed H

    2015-03-01

    Segregating F4 families from the cross between drought sensitive (Yecora Rojo) and drought tolerant (Pavon 76) genotypes were made to identify SSR markers linked to leaf chlorophyll content, flag leaf senescence and cell membrane stability traits in wheat (Triticum aestivum L.) under water-stressed condition and to map quantitative trait locus (QTL) for the three physiological traits. The parents and 150 F4 families were evaluated phenotypically for drought tolerance using two irrigation treatments (2500 and 7500 m3/ha). Using 400 SSR primers tested for polymorphism in testing parental and F4 families genotypes, the results revealed that QTL for leaf chlorophyll content, flag leaf senescence and cell membrane stability traits were associated with 12, 5 and 12 SSR markers, respectively and explained phenotypic variation ranged from 6 to 42%. The SSR markers for physiological traits had genetic distances ranged from 12.5 to 25.5 cM. These SSR markers can be further used in breeding programs for drought tolerance in wheat.

  15. Gender-Pay-Gap

    OpenAIRE

    Eicker, Jannis

    2017-01-01

    Der Gender-Pay-Gap ist eine statistische Kennzahl zur Messung der Ungleichheit zwischen Männern* und Frauen* beim Verdienst. Es gibt zwei Versionen: einen "unbereinigten" und einen "bereinigten". Der "unbereinigte" Gender-Pay-Gap berechnet den geschlechtsspezifischen Verdienstunterschied auf Basis der Bruttostundenlöhne aller Männer* und Frauen* der Grundgesamtheit. Beim "bereinigten" Wert hingegen werden je nach Studie verschiedene Faktoren wie Branche, Position und Berufserfahrung herausger...

  16. The Gender Pay Gap

    OpenAIRE

    Alan Manning

    2006-01-01

    Empirical research on gender pay gaps has traditionally focused on the role of gender-specific factors, particularly gender differences in qualifications and differences in the treatment of otherwise equally qualified male and female workers (i.e., labor market discrimination). This paper explores the determinants of the gender pay gap and argues for the importance of an additional factor, wage structure, the array of prices set for labor market skills and the rewards received for employment ...

  17. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  18. GAP: yet another image processing system for solar observations.

    Science.gov (United States)

    Keller, C. U.

    GAP is a versatile, interactive image processing system for analyzing solar observations, in particular extended time sequences, and for preparing publication quality figures. It consists of an interpreter that is based on a language with a control flow similar to PASCAL and C. The interpreter may be accessed from a command line editor and from user-supplied functions, procedures, and command scripts. GAP is easily expandable via external FORTRAN programs that are linked to the GAP interface routines. The current version of GAP runs on VAX, DECstation, Sun, and Apollo computers. Versions for MS-DOS and OS/2 are in preparation.

  19. Operative Links

    DEFF Research Database (Denmark)

    Wistoft, Karen; Højlund, Holger

    2012-01-01

    and have been the object of great expectations concerning the ability to incorporate health concerns into every welfare area through health promotion strategies. The paper draws on results and analyses of a collective research project funded by the Danish National Research Council and carried out...... links' that indicate cooperative levels which facilitate a creative and innovative effort in disease prevention and health promotion targeted at children and adolescents - across traditional professional boundaries. It is proposed that such links are supported by network structures, shared semantics...

  20. SRTC - Gap Analysis Table

    International Nuclear Information System (INIS)

    M.L. Johnson

    2005-01-01

    The purpose of this document is to review the existing SRTC design against the ''Nuclear Safety Design Bases for License Application'' (NSDB) [Ref. 10] requirements and to identify codes and standards and supplemental requirements to meet these requirements. If these codes and standards and supplemental requirements can not fully meet these safety requirements then a ''gap'' is identified. These gaps will be identified here and addressed using the ''Site Rail Transfer Cart (SRTC) Design Development Plan'' [Ref. 14]. The codes and standards, supplemental requirements, and design development requirements are provided in the SRTC and associated rails gap analysis table in Appendix A. Because SRTCs are credited with performing functions important to safety (ITS) in the NSDB [Ref. 10], design basis requirements are applicable to ensure equipment is available and performs required safety functions when needed. The gap analysis table is used to identify design objectives and provide a means to satisfy safety requirements. To ensure that the SRTC and rail design perform required safety Functions and meet performance criteria, this portion of the gap analysis table supplies codes and standards sections and the supplemental requirements and identifies design development requirements, if needed

  1. Clan structure analysis and rapidity gap probability

    International Nuclear Information System (INIS)

    Lupia, S.; Giovannini, A.; Ugoccioni, R.

    1995-01-01

    Clan structure analysis in rapidity intervals is generalized from negative binomial multiplicity distribution to the wide class of compound Poisson distributions. The link of generalized clan structure analysis with correlation functions is also established. These theoretical results are then applied to minimum bias events and evidentiate new interesting features, which can be inspiring and useful in order to discuss data on rapidity gap probability at TEVATRON and HERA. (orig.)

  2. Clan structure analysis and rapidity gap probability

    Energy Technology Data Exchange (ETDEWEB)

    Lupia, S. [Turin Univ. (Italy). Ist. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Turin (Italy); Giovannini, A. [Turin Univ. (Italy). Ist. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Turin (Italy); Ugoccioni, R. [Turin Univ. (Italy). Ist. di Fisica Teorica]|[Istituto Nazionale di Fisica Nucleare, Turin (Italy)

    1995-03-01

    Clan structure analysis in rapidity intervals is generalized from negative binomial multiplicity distribution to the wide class of compound Poisson distributions. The link of generalized clan structure analysis with correlation functions is also established. These theoretical results are then applied to minimum bias events and evidentiate new interesting features, which can be inspiring and useful in order to discuss data on rapidity gap probability at TEVATRON and HERA. (orig.)

  3. The longevity gender gap

    DEFF Research Database (Denmark)

    Aviv, Abraham; Shay, Jerry; Christensen, Kaare

    2005-01-01

    In this Perspective, we focus on the greater longevity of women as compared with men. We propose that, like aging itself, the longevity gender gap is exceedingly complex and argue that it may arise from sex-related hormonal differences and from somatic cell selection that favors cells more...... resistant to the ravages of time. We discuss the interplay of these factors with telomere biology and oxidative stress and suggest that an explanation for the longevity gender gap may arise from a better understanding of the differences in telomere dynamics between men and women....

  4. Gap junction diseases of the skin.

    NARCIS (Netherlands)

    Steensel, M.A.M. van

    2004-01-01

    Gap junctions are intercellular channels that allow the passage of water, ions, and small molecules. They are involved in quick, short-range messaging between cells and are found in skin, nervous tissue, heart, and muscle. An increasing number of hereditary skin disorders appear to be caused by

  5. Going against the flow: a critical analysis of inter-state virtual water trade in the context of India's national river linking programme

    NARCIS (Netherlands)

    Verma, Shilp; Kampman, Doeke A.; van der Zaag, Pieter; Hoekstra, Arjen Ysbert

    2009-01-01

    Virtual water trade has been promoted as a tool to address national and regional water scarcity. In the context of international (food) trade, this concept has been applied with a view to optimize the flow of commodities considering the water endowments of nations. The concept states that water rich

  6. Estimating Gender Wage Gaps

    Science.gov (United States)

    McDonald, Judith A.; Thornton, Robert J.

    2011-01-01

    Course research projects that use easy-to-access real-world data and that generate findings with which undergraduate students can readily identify are hard to find. The authors describe a project that requires students to estimate the current female-male earnings gap for new college graduates. The project also enables students to see to what…

  7. Determining the ’Gap

    Science.gov (United States)

    2009-05-01

    Army training doctrine, and by adjusting the curriculum of the officer core in order to close the knowledge gap . The author closes by concluding...fight. The research to find these gaps begins with a process trace of doctrine from 1976 to the present, starting with the advent of Active Defense...discovering the one gap , three were found. Upon further examination below, even these initially perceived gaps dissipate under close scrutiny. Gap

  8. Water

    Science.gov (United States)

    ... drink and water in food (like fruits and vegetables). 6. Of all the earth’s water, how much is ocean or seas? 97 percent of the earth’s water is ocean or seas. 7. How much of the world’s water is frozen? Of all the water on earth, about 2 percent is frozen. 8. How much ...

  9. Experimental Determination of Temperatures in a Liquid GAP

    International Nuclear Information System (INIS)

    Masson, Viviana; Ojeda, Andres; Fabian, Bonetto

    2003-01-01

    An experimental study of heat transfer in a gap of water at atmospheric pressure is presented under natural convection conditions.The objective of the work was to experimentally determine the expected maximum temperatures in the gap for a given heater power.The experimental set-up was a plane surface heated by resistances and facing a 1mm-liquid gap.Visualisation of phenomena by video and still picture was performed

  10. Water

    International Nuclear Information System (INIS)

    Chovanec, A.; Grath, J.; Kralik, M.; Vogel, W.

    2002-01-01

    An up-date overview of the situation of the Austrian waters is given by analyzing the status of the water quality (groundwater, surface waters) and water protection measures. Maps containing information of nitrate and atrazine in groundwaters (analyses at monitoring stations), nitrate contents and biological water quality of running waters are included. Finally, pollutants (nitrate, orthophosphate, ammonium, nitrite, atrazine etc.) trends in annual mean values and median values for the whole country for the years 1992-1999 are presented in tables. Figs. 5. (nevyjel)

  11. Mind the Gap!

    DEFF Research Database (Denmark)

    Schmidt, Kjeld; Simone, Carla

    2000-01-01

    CSCW at large seems to be pursuing two diverging strategies: on one hand a strategy aiming at coordination technologies that reduce the complexity of coordinating cooperative activities by regulating the coordinative interactions, and on the other hand a strategy that aims at radically flexible m...... and blended in the course of real world cooperative activities. On the basis of this discussion the paper outlines an approach which may help CSCW research to bridge this gap....... means of interaction which do not regulate interaction but rather leave it to the users to cope with the complexity of coordinating their activities. As both strategies reflect genuine requirements, we need to address the issue of how the gap can be bridged, that is, how the two strategies can...

  12. Closing the gap

    International Nuclear Information System (INIS)

    Moxon, Suzanne

    1999-01-01

    The problem of fish going through turbines at hydroelectric power plants and the growing concern over the survival rate of salmon at the US Army Corps operated Bonneville lock and dam on the Columbia river in the Pacific Northwest is discussed. The protection of the fish, the assessment of the hazards facing fish passing through turbines, the development of a new turbine, and improved turbine efficiency that reduces cavitation, turbulence and shear flow are examined. The closing of the gap between the turbine blades, hub and discharge ring to increase efficiency and reduce the risk to fish, and the development of the minimum gap runner (MGR) are described, and the lower maximum permitted power output of MGR is noted. (UK)

  13. Gender gap in entrepreneurship

    OpenAIRE

    Startienė, Gražina; Remeikienė, Rita

    2008-01-01

    The article considers a significant global issue - gender gap starting and developing own business. The field of business was for a long time reserved to men, thus, despite of an increasing number of female entrepreneurs during last decade, the number of female entrepreneurs in Europe, including Lithuania, remains lower than the one of male entrepreneurs. According to the data of various statistical sources, an average ratio of enterprises newly established by men and women in EU countries is...

  14. Mind the Gap

    Science.gov (United States)

    Fairbanks, Terry; Savage, Erica; Adams, Katie; Wittie, Michael; Boone, Edna; Hayden, Andrew; Barnes, Janey; Hettinger, Zach; Gettinger, Andrew

    2016-01-01

    Summary Objective Decisions made during electronic health record (EHR) implementations profoundly affect usability and safety. This study aims to identify gaps between the current literature and key stakeholders’ perceptions of usability and safety practices and the challenges encountered during the implementation of EHRs. Materials and Methods Two approaches were used: a literature review and interviews with key stakeholders. We performed a systematic review of the literature to identify usability and safety challenges and best practices during implementation. A total of 55 articles were reviewed through searches of PubMed, Web of Science and Scopus. We used a qualitative approach to identify key stakeholders’ perceptions; semi-structured interviews were conducted with a diverse set of health IT stakeholders to understand their current practices and challenges related to usability during implementation. We used a grounded theory approach: data were coded, sorted, and emerging themes were identified. Conclusions from both sources of data were compared to identify areas of misalignment. Results We identified six emerging themes from the literature and stakeholder interviews: cost and resources, risk assessment, governance and consensus building, customization, clinical work-flow and usability testing, and training. Across these themes, there were misalignments between the literature and stakeholder perspectives, indicating major gaps. Discussion Major gaps identified from each of six emerging themes are discussed as critical areas for future research, opportunities for new stakeholder initiatives, and opportunities to better disseminate resources to improve the implementation of EHRs. Conclusion Our analysis identified practices and challenges across six different emerging themes, illustrated important gaps, and results suggest critical areas for future research and dissemination to improve EHR implementation. PMID:27847961

  15. Water

    Science.gov (United States)

    ... can be found in some metal water taps, interior water pipes, or pipes connecting a house to ... reduce or eliminate lead. See resources below. 5. Children and pregnant women are especially vulnerable to the ...

  16. MV controlled spark gap

    International Nuclear Information System (INIS)

    Evdokimovich, V.M.; Evlampiev, S.B.; Korshunov, G.S.; Nikolaev, V.A.; Sviridov, Yu.F.; Khmyrov, V.V.

    1980-01-01

    A megavolt gas-filled trigatron gap with a sectional gas-discharge chamber having a more than three-fold range of operating voltages is described. The discharge chamber consists of ten sections, each 70 mm thick, made of organic glass. The sections are separated one from another by aluminium gradient rings to which ohmic voltage divider is connected. Insulational sections and gradient rings are braced between themselves by means of metal flanges through gaskets made of oil-resistant rubber with the help of fiberglass-laminate pins. The gap has two electrodes 110 mm in diameter. The trigatron ignition assembly uses a dielectric bushing projecting over the main electrode plane. Use has been made of a gas mixture containing 10% of SF 6 and 90% of air making possible to ensure stable gap operation without readjusting in the voltage range from 0.4 to 1.35 MV. The operation time lag in this range is equal to 10 μs at a spread of [ru

  17. What is the Mass of a Gap-opening Planet?

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Ruobing [Steward Observatory, University of Arizona, Tucson, AZ (United States); Fung, Jeffrey, E-mail: rdong@email.arizona.edu [Department of Astronomy, University of California, Berkeley, CA (United States)

    2017-02-01

    High-contrast imaging instruments such as GPI and SPHERE are discovering gap structures in protoplanetary disks at an ever faster pace. Some of these gaps may be opened by planets forming in the disks. In order to constrain planet formation models using disk observations, it is crucial to find a robust way to quantitatively back out the properties of the gap-opening planets, in particular their masses, from the observed gap properties, such as their depths and widths. Combining 2D and 3D hydrodynamics simulations with 3D radiative transfer simulations, we investigate the morphology of planet-opened gaps in near-infrared scattered-light images. Quantitatively, we obtain correlations that directly link intrinsic gap depths and widths in the gas surface density to observed depths and widths in images of disks at modest inclinations under finite angular resolution. Subsequently, the properties of the surface density gaps enable us to derive the disk scale height at the location of the gap h , and to constrain the quantity M {sub p}{sup 2}/ α , where M {sub p} is the mass of the gap-opening planet and α characterizes the viscosity in the gap. As examples, we examine the gaps recently imaged by VLT/SPHERE, Gemini/GPI, and Subaru/HiCIAO in HD 97048, TW Hya, HD 169142, LkCa 15, and RX J1615.3-3255. Scale heights of the disks and possible masses of the gap-opening planets are derived assuming each gap is opened by a single planet. Assuming α = 10{sup −3}, the derived planet masses in all cases are roughly between 0.1 and 1 M {sub J}.

  18. Non-metallic gage for gap

    International Nuclear Information System (INIS)

    Hiroki, Hideo.

    1996-01-01

    The present invention concerns a non-metallic gage for detecting a gap which can not be seen from the out side such as a gap between a water pipe and fuel rods without damaging an objective material as to whether the gap is formed within a standard value or not. The gage is made of a synthetic resin, for example, polyacetal having such a hardness as not damaging the objective material and endurable to repeating flexure upon use. The gage comprises a short gage portion having a predetermined standard thickness and an flexible extended connection portion reduced in the thickness. Provision of the extended connection portion enables wide range flexure thereof such as ±60deg relative to insertion direction during insertion operation upon testing to solve a drawback in the prior art such as worry of breakage of the gage, thereby enabling to conduct inspection rapidly at high reliability. (N.H.)

  19. CASE STUDY: China — Bridging the Gap between Scientists and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-01-05

    Jan 5, 2011 ... CASE STUDY: China — Bridging the Gap between Scientists and ... the right inputs of water, fertilizer, and pesticides to maximize yields. ... Some are rare and unique to the area, such as black wax maize and mountain lily.

  20. Understanding the "Family Gap" in Pay for Women with Children

    OpenAIRE

    Jane Waldfogel

    1998-01-01

    As the gender gap in pay between women and men has been narrowing, the 'family gap' in pay between mothers and nonmothers has been widening. One reason may be the institutional structure in the United States, which has emphasized equal pay and opportunity policies but not family policies, in contrast to other countries that have implemented both. The authors now have evidence on the links between one such family policy and women's pay. Recent research suggests that maternity leave coverage, b...

  1. GapBlaster-A Graphical Gap Filler for Prokaryote Genomes.

    Directory of Open Access Journals (Sweden)

    Pablo H C G de Sá

    Full Text Available The advent of NGS (Next Generation Sequencing technologies has resulted in an exponential increase in the number of complete genomes available in biological databases. This advance has allowed the development of several computational tools enabling analyses of large amounts of data in each of the various steps, from processing and quality filtering to gap filling and manual curation. The tools developed for gap closure are very useful as they result in more complete genomes, which will influence downstream analyses of genomic plasticity and comparative genomics. However, the gap filling step remains a challenge for genome assembly, often requiring manual intervention. Here, we present GapBlaster, a graphical application to evaluate and close gaps. GapBlaster was developed via Java programming language. The software uses contigs obtained in the assembly of the genome to perform an alignment against a draft of the genome/scaffold, using BLAST or Mummer to close gaps. Then, all identified alignments of contigs that extend through the gaps in the draft sequence are presented to the user for further evaluation via the GapBlaster graphical interface. GapBlaster presents significant results compared to other similar software and has the advantage of offering a graphical interface for manual curation of the gaps. GapBlaster program, the user guide and the test datasets are freely available at https://sourceforge.net/projects/gapblaster2015/. It requires Sun JDK 8 and Blast or Mummer.

  2. Gap Analysis Bulletin No. 13

    Science.gov (United States)

    2005-12-01

    we would like to web developer; gather comments from GAP researchers and data users. We are * facilitate collaboration among GAP projects by...N.Y. Research Grant #012/01 A. 42 Gap Analysis Bulletin No. 13, December 2005 Ga pAnalysis Smith, S. D., W. A. Brown, C. R. Smith, and M. E. Richmond... GAP will be focusing activities have greatly reduced the habitat available to support on the enduring features of the Great Lakes basin. Influences

  3. The homeownership gap

    OpenAIRE

    Andrew F. Haughwout; Richard Peach; Joseph Tracy

    2009-01-01

    After rising for a decade, the U.S. homeownership rate peaked at 69 percent in the third quarter of 2006. Over the next two and a half years, as home prices fell in many parts of the country and the unemployment rate rose sharply, the homeownership rate declined by 1.7 percentage points. An important question is, how much more will this rate decline over the current economic downturn? To address this question, we propose the concept of the 'homeownership gap' as a gauge of downward pressure o...

  4. Gaps in nonsymmetric numerical semigroups

    International Nuclear Information System (INIS)

    Fel, Leonid G.; Aicardi, Francesca

    2006-12-01

    There exist two different types of gaps in the nonsymmetric numerical semigroups S(d 1 , . . . , d m ) finitely generated by a minimal set of positive integers {d 1 , . . . , d m }. We give the generating functions for the corresponding sets of gaps. Detailed description of both gap types is given for the 1st nontrivial case m = 3. (author)

  5. The Politics of Achievement Gaps

    DEFF Research Database (Denmark)

    Valant, J.; Newark, D. A.

    2016-01-01

    on achievement gaps have received little attention from researchers, despite playing an important role in shaping policymakers’ behaviors. Drawing on randomized experiments with a nationally representative sample of adults, we explore the public’s beliefs about test score gaps and its support for gap...

  6. Bridging the Gaps.

    Science.gov (United States)

    Netzer, Greg

    1995-01-01

    Discusses a model water quality monitoring project, Project Bridge, established to train minority girls about to enter eighth grade in scientific procedures followed by hands-on experimentation. Students spent a week monitoring water in an urban stream and analyzing results. (LZ)

  7. Anisohydric water use behavior links growing season evaporative demand to ring-width increment in conifers from summer-dry environments

    Science.gov (United States)

    Steve L. Voelker; R. Justin DeRose; Matthew F. Bekker; Chalita Sriladda; Nisa Leksungnoen; Roger K. Kjelgren

    2018-01-01

    Conifers in the Pinaceae and Cupressaceae from dry environments have been shown to broadly differ in their stomatal sensitivity to soil drying that result in isohydric versus anisohydric water use behavior, respectively. Here, we first employ a series of drought experiments and field observations to confirm the degree of isohydric versus anisohydric water use behavior...

  8. GAP-REACH

    Science.gov (United States)

    Lewis-Fernández, Roberto; Raggio, Greer A.; Gorritz, Magdaliz; Duan, Naihua; Marcus, Sue; Cabassa, Leopoldo J.; Humensky, Jennifer; Becker, Anne E.; Alarcón, Renato D.; Oquendo, María A.; Hansen, Helena; Like, Robert C.; Weiss, Mitchell; Desai, Prakash N.; Jacobsen, Frederick M.; Foulks, Edward F.; Primm, Annelle; Lu, Francis; Kopelowicz, Alex; Hinton, Ladson; Hinton, Devon E.

    2015-01-01

    Growing awareness of health and health care disparities highlights the importance of including information about race, ethnicity, and culture (REC) in health research. Reporting of REC factors in research publications, however, is notoriously imprecise and unsystematic. This article describes the development of a checklist to assess the comprehensiveness and the applicability of REC factor reporting in psychiatric research publications. The 16-itemGAP-REACH© checklist was developed through a rigorous process of expert consensus, empirical content analysis in a sample of publications (N = 1205), and interrater reliability (IRR) assessment (N = 30). The items assess each section in the conventional structure of a health research article. Data from the assessment may be considered on an item-by-item basis or as a total score ranging from 0% to 100%. The final checklist has excellent IRR (κ = 0.91). The GAP-REACH may be used by multiple research stakeholders to assess the scope of REC reporting in a research article. PMID:24080673

  9. Gap Task Force

    CERN Multimedia

    Lissuaer, D

    One of the more congested areas in the ATLAS detector is the GAP region (the area between the Barrel Calorimeter and the End Cap calorimeter) where Inner Detector services, LAr Services and some Tile services all must co-habitat in a very limited area. It has been clear for some time that the space in the GAP region is not sufficient to accommodate all that is needed. In the last few month additional problems of routing all the services to Z=0 have been encountered due to the very limited space between the Tile Calorimeter and the first layer of Muon chambers. The Technical Management Board (TMB) and the Executive Board (EB) decided in the middle of March to establish a Task Force to look at this problem and come up with a solution within well-specified guidelines. The task force consisted of experts from the ID, Muon, Liquid Argon and Tile systems in addition to experts from the Technical Coordination team and the Physics coordinator. The task force held many meetings and in general there were some very l...

  10. Closing the value gap

    International Nuclear Information System (INIS)

    Snyder, A.V.

    1992-01-01

    It's a predicament. For the most part, investor-owned electric utilities trade at a deep discount to the actual (that is, replacement-cost) value to their assets. That's because most utilities fail to earn real returns large enough to justify raising and investing capital. The result is a value gap, where overall market value is significantly lower than the replacement costs of the assets. This gap is wider for utilities than for virtually any other industry in our economy. In addition to providing education and awareness, senior management must determine which businesses and activities create value and which diminish it. Then, management must allocate capital and human resources appropriately, holding down investments in value-diminishing areas until they can improve their profitability, and aggressively investing in value-enhancing businesses while preserving their profitability. But value management must not stop with resource-allocation decisions. To create a lasting transition to a value management philosophy, the utility's compensation system must also change: executives will have motivation to create value when compensation stems from this goal, not from such misleading accounting measures as earnings-per-share growth or ROE. That requires clear value-creation goals, and the organization must continuously evaluate top management's performance in light of the progress made toward those goals

  11. Soil moisture in sessile oak forest gaps

    Science.gov (United States)

    Zagyvainé Kiss, Katalin Anita; Vastag, Viktor; Gribovszki, Zoltán; Kalicz, Péter

    2015-04-01

    By social demands are being promoted the aspects of the natural forest management. In forestry the concept of continuous forest has been an accepted principle also in Hungary since the last decades. The first step from even-aged stand to continuous forest can be the forest regeneration based on gap cutting, so small openings are formed in a forest due to forestry interventions. This new stand structure modifies the hydrological conditions for the regrowth. Without canopy and due to the decreasing amounts of forest litter the interception is less significant so higher amount of precipitation reaching the soil. This research focuses on soil moisture patterns caused by gaps. The spatio-temporal variability of soil water content is measured in gaps and in surrounding sessile oak (Quercus petraea) forest stand. Soil moisture was determined with manual soil moisture meter which use Time-Domain Reflectometry (TDR) technology. The three different sizes gaps (G1: 10m, G2: 20m, G3: 30m) was opened next to Sopron on the Dalos Hill in Hungary. First, it was determined that there is difference in soil moisture between forest stand and gaps. Second, it was defined that how the gap size influences the soil moisture content. To explore the short term variability of soil moisture, two 24-hour (in growing season) and a 48-hour (in dormant season) field campaign were also performed in case of the medium-sized G2 gap along two/four transects. Subdaily changes of soil moisture were performed. The measured soil moisture pattern was compared with the radiation pattern. It was found that the non-illuminated areas were wetter and in the dormant season the subdaily changes cease. According to our measurements, in the gap there is more available water than under the forest stand due to the less evaporation and interception loss. Acknowledgements: The research was supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0004 and AGRARKLIMA.2 VKSZ_12-1-2013-0034.

  12. Water

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available Water scarcity is without a doubt on of the greatest threats to the human species and has all the potential to destabilise world peace. Falling water tables are a new phenomenon. Up until the development of steam and electric motors, deep groudwater...

  13. Water

    OpenAIRE

    Hertie School of Governance

    2010-01-01

    All human life depends on water and air. The sustainable management of both is a major challenge for today's public policy makers. This issue of Schlossplatz³ taps the streams and flows of the current debate on the right water governance.

  14. Board affiliation and pay gap

    Directory of Open Access Journals (Sweden)

    Shenglan Chen

    2014-06-01

    Full Text Available This paper examines the effects of board affiliation on the corporate pay gap. Using a sample of Chinese listed firms from 2005 to 2011, we find that boards with a greater presence of directors appointed by block shareholders have lower pay gaps. Furthermore, the governance effects of board affiliation with and without pay are distinguished. The empirical results show that board affiliation without pay is negatively related to the pay gap, while board affiliation with pay is positively related to the pay gap. Overall, the results shed light on how block shareholders affect their companies’ pay gaps through board affiliation.

  15. Causes of Domestic Water Consumption Trends in the City of Alicante: Exploring the Links between the Housing Bubble, the Types of Housing and the Socio-Economic Factors

    Directory of Open Access Journals (Sweden)

    Álvaro-Francisco Morote

    2016-08-01

    Full Text Available The European Mediterranean coastline has experienced major tourism-related urbanization since 1960. This is a dynamic that has led to increased spending on water consumption for urban and tourism-related uses. The objective of this paper is to define and to analyze how domestic water consumption in the city of Alicante evolved between 2000 and 2013. Real billing figures for individual households were analyzed according to the type of housing and the income level of the occupants. The conclusions drawn show that consumption fell over the period studied, and that there are different patterns in water expenditure depending on the type of housing and the inhabitants.

  16. Minding the gap

    Directory of Open Access Journals (Sweden)

    Mia Carlberg

    2013-12-01

    Full Text Available The plan for the Round table session was to focus on organizational and social/cultural differences between librarians and faculty with the aim to increase our awareness of the differences when we try to find ways to cooperate within the academy or school. This may help us to sort things out, experience acceptance and take adequate actions, saving energy and perhaps be less frustrated.  The questions that the workshop addressed were: What is in the gap between librarians and faculty when dealing with information literacy? How can we fill the gap? Participants discussed this in detail with the aim of together finding ways to understand it better and make it possible to find ways to fill this gap. By defining it and thereby making it easier to work out a strategy for future action to improve the teaching of information literacy, including listing possible, impossible or nearly impossible ways. The springboard to the discussion was extracted from some projects that the workshop leader has been engaged in since 2009. The first example is a research circle where Uppsala University Library used action research to observe and understand the process when we had the opportunity to implement information literacy classes with progression in an undergraduate program. What worked well? What did not? Why? This work was described together with other examples from Uppsala University to an international panel working with quality issues. What did they think of our work? May this change the ways we are working? How? Another example is an ongoing joint project where librarians and faculty members are trying to define ways to increase the cooperation between the library and faculty and make this cooperation sustainable. Recent experience from this was brought to the discussion.   There are an overwhelming number of papers written in this field. A few papers have inspired these ideas. One article in particular: Christiansen, L., Stombler, M. & Thaxton, L. (2004. A

  17. A systematic approach for the assessment of bacterial growth-controlling factors linked to biological stability of drinking water in distribution systems

    KAUST Repository

    Prest, E. I.; Hammes, F.; Kotzsch, S.; van Loosdrecht, M. C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    A systematic approach is presented for the assessment of (i) bacterial growth-controlling factors in drinking water and (ii) the impact of distribution conditions on the extent of bacterial growth in full-scale distribution systems. The approach

  18. Bridging the Evaluation Gap

    Directory of Open Access Journals (Sweden)

    Paul Wouters

    2017-02-01

    Full Text Available Paul Wouters’ essay is concerned with bridging the gap between what we value in our academic work and how we are assessed in formal evaluation exercises. He reflects on the recent evaluation of his own center, and reminds us that it is productive to see evaluations not as the (obviously impossible attempt to produce a true representation of past work, but rather as the exploration and performance of “who one wants to be.” Reflecting on why STS should do more than just play along to survive in the indicator game, he suggests that our field should contribute to changing its very rules. In this endeavor, the attitude and sensibilities developed in our field may be more important than any specific theoretical concepts or methodologies.

  19. The GAP-TPC

    International Nuclear Information System (INIS)

    Rossi, B.; Anastasio, A.; Boiano, A.; Cocco, A.G.; Meo, P. Di; Vanzanella, A.; Catalanotti, S.; Covone, G.; Longo, G.; Walker, S.; Fiorillo, G.; Wang, H.; Wang, Y.

    2016-01-01

    Several experiments have been conducted worldwide, with the goal of observing low-energy nuclear recoils induced by WIMPs scattering off target nuclei in ultra-sensitive, low-background detectors. In the last few decades noble liquid detectors designed to search for dark matter in the form of WIMPs have been extremely successful in improving their sensitivities and setting the best limits. One of the crucial problems to be faced for the development of large size (multi ton-scale) liquid argon experiments is the lack of reliable and low background cryogenic PMTs: their intrinsic radioactivity, cost, and borderline performance at 87 K rule them out as a possible candidate for photosensors. We propose a brand new concept of liquid argon-based detector for direct dark matter search: the Geiger-mode Avalanche Photodiode Time Projection Chamber (GAP-TPC) optimized in terms of residual radioactivity of the photosensors, energy and spatial resolution, light and charge collection efficiency

  20. Gaps in Political Interest

    DEFF Research Database (Denmark)

    Robison, Joshua

    2015-01-01

    Political interest fundamentally influences political behavior, knowledge, and persuasion (Brady, Verba, & Schlozman, 1995; Delli Carpini & Keeter, 1996; Luskin, 1990; Zukin, Andolina, Keeter, Jenkins, & Delli Carpini, 2006). Since the early 1960s, the American National Election Studies (ANES) has...... sought to measure respondents’ general interest in politics by asking them how often they follow public affairs. In this article, we uncover novel sources of measurement error concerning this question. We first show that other nationally representative surveys that frequently use this item deliver...... drastically higher estimates of mass interest. We then use a survey experiment included on a wave of the ANES’ Evaluating Government and Society Surveys (EGSS) to explore the influence of question order in explaining this systemic gap in survey results. We show that placing batteries of political...

  1. Water

    Directory of Open Access Journals (Sweden)

    E. Sanmuga Priya

    2017-05-01

    Full Text Available Phytoremediation through aquatic macrophytes treatment system (AMATS for the removal of pollutants and contaminants from various natural sources is a well established environmental protection technique. Water hyacinth (Eichhornia crassipes, a worst invasive aquatic weed has been utilised for various research activities over the last few decades. The biosorption capacity of the water hyacinth in minimising various contaminants present in the industrial wastewater is well studied. The present review quotes the literatures related to the biosorption capacity of the water hyacinth in reducing the concentration of dyestuffs, heavy metals and minimising certain other physiochemical parameters like TSS (total suspended solids, TDS (total dissolved solids, COD (chemical oxygen demand and BOD (biological oxygen demand in textile wastewater. Sorption kinetics through various models, factors influencing the biosorption capacity, and role of physical and chemical modifications in the water hyacinth are also discussed.

  2. The inverse F-BAR domain protein srGAP2 acts through srGAP3 to modulate neuronal differentiation and neurite outgrowth of mouse neuroblastoma cells.

    Directory of Open Access Journals (Sweden)

    Yue Ma

    Full Text Available The inverse F-BAR (IF-BAR domain proteins srGAP1, srGAP2 and srGAP3 are implicated in neuronal development and may be linked to mental retardation, schizophrenia and seizure. A partially overlapping expression pattern and highly similar protein structures indicate a functional redundancy of srGAPs in neuronal development. Our previous study suggests that srGAP3 negatively regulates neuronal differentiation in a Rac1-dependent manner in mouse Neuro2a cells. Here we show that exogenously expressed srGAP1 and srGAP2 are sufficient to inhibit valporic acid (VPA-induced neurite initiation and growth in the mouse Neuro2a cells. While ectopic- or over-expression of RhoGAP-defective mutants, srGAP1(R542A and srGAP2(R527A exert a visible inhibitory effect on neuronal differentiation. Unexpectedly, knockdown of endogenous srGAP2 fails to facilitate the neuronal differentiation induced by VPA, but promotes neurite outgrowth of differentiated cells. All three IF-BAR domains from srGAP1-3 can induce filopodia formation in Neuro2a, but the isolated IF-BAR domain from srGAP2, not from srGAP1 and srGAP3, can promote VPA-induced neurite initiation and neuronal differentiation. We identify biochemical and functional interactions of the three srGAPs family members. We propose that srGAP3-Rac1 signaling may be required for the effect of srGAP1 and srGAP2 on attenuating neuronal differentiation. Furthermore, inhibition of Slit-Robo interaction can phenocopy a loss-of-function of srGAP3, indicating that srGAP3 may be dedicated to the Slit-Robo pathway. Our results demonstrate the interplay between srGAP1, srGAP2 and srGAP3 regulates neuronal differentiation and neurite outgrowth. These findings may provide us new insights into the possible roles of srGAPs in neuronal development and a potential mechanism for neurodevelopmental diseases.

  3. Technique for estimating relocated gap width for gap conductance calculations

    International Nuclear Information System (INIS)

    Klink, P.H.

    1978-01-01

    Thermally induced fuel fragmentation and relocation has been demonstrated to influence the thermal behavior of a fuel rod in two ways. The effective fuel pellet conductivity is decreased and pellet-to-cladding heat transfer is improved. This paper presents a correlation between as-built and relocated gap width which, used with the Ross and Stoute Gap Conductance Correlation and an appropriate fuel thermal expansion model, closely predicts the measured gap conductances

  4. Binding water to a PEG-linked flexible bichromophore: IR spectra of diphenoxyethane-(H{sub 2}O){sub n} clusters, n = 2-4

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Patrick S.; Buchanan, Evan G.; Gord, Joseph R.; Zwier, Timothy S., E-mail: zwier@purdue.edu [Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084 (United States)

    2015-04-21

    The single-conformation infrared (IR) and ultraviolet (UV) spectroscopies of neutral 1,2-diphenoxyethane-(H{sub 2}O){sub n} clusters with n = 2-4 (labeled henceforth as 1:n) have been studied in a molecular beam using a combination of resonant two-photon ionization, IR-UV holeburning, and resonant ion-dip infrared (RIDIR) spectroscopies. Ground state RIDIR spectra in the OH and CH stretch regions were used to provide firm assignments for the structures of the clusters by comparing the experimental spectra with the predictions of calculations carried out at the density functional M05-2X/6-31+G(d) level of theory. At all sizes in this range, the water molecules form water clusters in which all water molecules engage in a single H-bonded network. Selective binding to the tgt monomer conformer of 1,2-diphenoxyethane (C{sub 6}H{sub 5}-O-CH{sub 2}-CH{sub 2}-O-C{sub 6}H{sub 5}, DPOE) occurs, since this conformer provides a binding pocket in which the two ether oxygens and two phenyl ring π clouds can be involved in stabilizing the water cluster. The 1:2 cluster incorporates a water dimer “chain” bound to DPOE much as it is in the 1:1 complex [E. G. Buchanan et al., J. Phys. Chem. Lett. 4, 1644 (2013)], with primary attachment via a double-donor water that bridges the ether oxygen of one phenoxy group and the π cloud of the other. Two conformers of the 1:3 cluster are observed and characterized, one that extends the water chain to a third molecule (1:3 chain) and the other incorporating a water trimer cycle (1:3 cycle). A cyclic water structure is also observed for the 1:4 cluster. These structural characterizations provide a necessary foundation for studies of the perturbations imposed on the two close-lying S{sub 1}/S{sub 2} excited states of DPOE considered in the adjoining paper [P. S. Walsh et al., J. Chem. Phys. 142, 154304 (2015)].

  5. A systematic approach for the assessment of bacterial growth-controlling factors linked to biological stability of drinking water in distribution systems

    KAUST Repository

    Prest, E. I.

    2016-01-06

    A systematic approach is presented for the assessment of (i) bacterial growth-controlling factors in drinking water and (ii) the impact of distribution conditions on the extent of bacterial growth in full-scale distribution systems. The approach combines (i) quantification of changes in autochthonous bacterial cell concentrations in full-scale distribution systems with (ii) laboratoryscale batch bacterial growth potential tests of drinking water samples under defined conditions. The growth potential tests were done by direct incubation of water samples, without modification of the original bacterial flora, and with flow cytometric quantification of bacterial growth. This method was shown to be reproducible (ca. 4% relative standard deviation) and sensitive (detection of bacterial growth down to 5 μg L-1 of added assimilable organic carbon). The principle of step-wise assessment of bacterial growth-controlling factors was demonstrated on bottled water, shown to be primarily carbon limited at 133 (±18) × 103 cells mL-1 and secondarily limited by inorganic nutrients at 5,500 (±1,700) × 103 cells mL-1. Analysis of the effluent of a Dutch full-scale drinking water treatment plant showed (1) bacterial growth inhibition as a result of end-point chlorination, (2) organic carbon limitation at 192 (±72) × 103 cells mL-1 and (3) inorganic nutrient limitation at 375 (±31) × 103 cells mL-1. Significantly lower net bacterial growth was measured in the corresponding full-scale distribution system (176 (±25) × 103 cells mL-1) than in the laboratory-scale growth potential test of the same water (294 (±35) × 103 cells mL-1), highlighting the influence of distribution on bacterial growth. The systematic approach described herein provides quantitative information on the effect of drinking water properties and distribution system conditions on biological stability, which can assist water utilities in decision-making on treatment or distribution system improvements to

  6. Sex-linked dominant

    Science.gov (United States)

    Inheritance - sex-linked dominant; Genetics - sex-linked dominant; X-linked dominant; Y-linked dominant ... can be either an autosomal chromosome or a sex chromosome. It also depends on whether the trait ...

  7. Advances, gaps, and future prospects in biological soil crust research

    Science.gov (United States)

    Weber, Bettina; Büdel, Burkhard; Belnap, Jayne

    2017-04-01

    Research progress has led to the understanding that biological soil crusts (biocrusts) are often complete miniature ecosystems comprising a variety of photosynthesizers (cyanobacteria, algae, lichens, bryophytes), decomposers like bacteria, fungi, and archaea, and heterotrophic organisms, like protozoa, nematodes, and microarthropods feeding on them. Biocrusts are one of the oldest terrestrial ecosystems, playing central roles in the structure and functioning of dryland ecosystems and presumably also influencing global biogeochemical cycles. On the other hand, biocrusts have been shown to be highly sensitive to global change, being easily destroyed by mechanical disturbance and severely threatened by minor changes in climate patterns. Despite the large increase in biocrust research, we still see major knowledge gaps which need to be tackled. Considering biodiversity studies, there are major regions of potential biocrust occurrence, where hardly any studies have been conducted. Molecular identification techniques are increasingly employed, but genetically characterized entities need to be linked with morphologically identified organisms to identify their ecological roles. Although there is a large body of research on the role of biocrusts in water and nutrient budgets, we are still far from closing the overall cycles. Results suggest that not all mechanisms have been identified, yet, leading to sometimes contradictory results between different studies. Knowledge on how to minimize impact to biocrusts during surface-disturbing activities has hardly been gained, and despite research efforts, instructions on effective biocrust restoration are still exemplary. In order to fill these research gaps, novel scientific approaches are needed. We expect that global research networks could be extremely helpful to answer scientific questions by tackling them within different regions, utilizing the same methodological techniques. Global networks could also be used for long

  8. The Adaptation Finance Gap Report

    DEFF Research Database (Denmark)

    UNEP’s Adaptation Gap Report series focuses on Finance, Technology and Knowledge gaps in climate change adaptation. It compliments the Emissions Gap Report series, and explores the implications of failing to close the emissions gap. The report builds on a 2014 assessment by the United Nations...... Environment Programme (UNEP), which laid out the concept of ‘adaptation gaps’ and outlined three such gaps: technology, finance and knowledge. The 2016 Adaptation Gap Report assesses the difference between the financial costs of adapting to climate change in developing countries and the amount of money...... actually available to meet these costs – a difference known as the “adaptation finance gap”. Like the 2014 report, the 2016 report focuses on developing countries, where adaptation capacity is often the lowest and needs the highest, and concentrates on the period up to 2050. The report identifies trends...

  9. Southwest Pacific deep water carbonate chemistry linked to high southern latitude climate and atmospheric CO2 during the Last Glacial Termination

    Science.gov (United States)

    Allen, Katherine A.; Sikes, Elisabeth L.; Hönisch, Bärbel; Elmore, Aurora C.; Guilderson, Thomas P.; Rosenthal, Yair; Anderson, Robert F.

    2015-08-01

    A greater amount of CO2 was stored in the deep sea during glacial periods, likely via greater efficiency of the biologic pump and increased uptake by a more alkaline ocean. Reconstructing past variations in seawater carbonate ion concentration (a major component of alkalinity) enables quantification of the relative roles of different oceanic CO2 storage mechanisms and also places constraints on the timing, magnitude, and location of subsequent deep ocean ventilation. Here, we present a record of deep-water inorganic carbon chemistry since the Last Glacial Maximum (LGM; ∼19-23 ka BP), derived from sediment core RR0503-83 raised from 1627 m in New Zealand's Bay of Plenty. The core site lies within the upper limit of southern-sourced Circumpolar Deep Water (CDW), just below the lower boundary of Antarctic Intermediate Water (AAIW). We reconstruct past changes in bottom water inorganic carbon chemistry from the trace element and stable isotopic composition of calcite shells of the epibenthic foraminifer Cibicidoides wuellerstorfi. A record of ΔCO32-(ΔCO32- = [COCO32-] in situ - [CO32-] saturation) derived from the foraminiferal boron to calcium ratio (B/Ca) provides evidence for greater ice-age storage of respired CO2 and reveals abrupt deglacial shifts in [CO32-] in situ of up to 30 μmol/kg (5 times larger than the difference between average LGM and Holocene values). The rapidity of these changes suggests the influence of changing water mass structure and atmospheric circulation in addition to a decrease in CO2 content of interior waters.

  10. Identification of SSR and retrotransposon-based molecular markers linked to morphological characters in oily sunfl ower (Helianthus annuus L.) under natural and water-limited states.

    Science.gov (United States)

    Ali, Soleimani Gezeljeh; Darvishzadeh, Reza; Ebrahimi, Asa; Bihamta, Mohammad Reza

    2018-03-01

    Sunflower is an important source of edible oil. Drought is known as an important factor limiting the growth and productivity of field crops in most parts of the world. Agricultural biotechnology mainly aims at developing crops with higher tolerance to the challenging environmental conditions, such as drought. This study examined a number of morphological characters, along with relative water content (RWC) in 100 inbred sunflower lines. A 10 × 10 simple lattice design with two replications was employed to measure the mentioned parameters under natural and water-limited states during two successive years. In molecular trial, 30 simple sequence repeat (SSR) primer pairs, as well as 14 inter-retrotransposon amplified polymorphism (IRAP) and 14 retrotransposon-microsatellite amplified polymorphism (REMAP) primer combinations were used for DNA fingerprinting of the lines. Most of the examined characters had lower average values under water-limited than natural states. Maximum and minimum reductions were observed in the cases of yield and oil percentage, respectively. The broad-sense heritabilities for all the examined characters were 0.20-0.73 and 0.10-0.34 under natural and water-limited states, respectively. In the studied samples, 8.97% of the 435 possible locus pairs of the SSRs represented significant linkage disequilibrium (LD) levels. In the association analysis using SSR markers, 22 and 21 markers were identified (P ≤ 0.05) for the studied characters under natural and water-limited states, respectively. The corresponding values were 50 and 37 using retrotransposon-based molecular markers. Some detected markers were communal between the characters under water-limited and natural states. This was in line with the phenotypic correlations detected between the characters. Communal markers facilitate the simultaneous selection of several characters and can thus improve the efficacy of selection based on markers in the plant-breeding activities.

  11. The influence of tagasaste (chamaecytisus proliferus link) trees on the water balance of an alley cropping system on deep sand in south-western Australia)

    International Nuclear Information System (INIS)

    Lefroy, E.C.; Pate, J.S.; Stirzaker, R.J.

    2001-01-01

    Components of the water balance of an alley cropping system were measured to assess the extent to which tree rows 30 m apart with access to a fresh, perched watertable at 5 m depth were able to capture deep drainage from an inter-cropped cereal-legume rotation. Neutron probe data showed that the 4-year-old trees, cut back to 0.6-m high at the beginning of the experiment, depleted soil water to 2, 4, and 8 m laterally from the tree rows in their first, second, and third years of coppice regrowth, respectively. Combining data from soil water depletion in summer and comparisons of deuterium/hydrogen ratios of groundwater, xylem sap of trees, and herbaceous plants, it was shown that tagasaste trees drew on soil water for 80% of their transpiration in the first winter and 40% in the second, while switching to near total dependence on groundwater each summer and early autumn. Tree water use on a whole plot basis was 170 mm in 1997 (68% from groundwater) v. 167 mm in 1998 (73% from groundwater). Recharge to the perched watertable was estimated to be 193 mm under sole crop in 1998 (52% of rainfall), reducing to 32 mm when uptake of groundwater by trees was included. The degree of complementarity between tagasaste trees and crops in alley cropping used for water management is quantified for 1998 by calculating the ratio of the distance over which trees reduced drainage to zero to the distance over which they reduced crop yield to zero. It is concluded that segregated monocultures of trees and crops would be a more appropriate strategy than a closely integrated system such as alley cropping in this case. Copyright (2001) CSIRO Australia

  12. Source Country Differences in Test Score Gaps: Evidence from Denmark

    Science.gov (United States)

    Rangvid, Beatrice Schindler

    2010-01-01

    We combine data from three studies for Denmark in the PISA 2000 framework to investigate differences in the native-immigrant test score gap by country of origin. In addition to the controls available from PISA data sources, we use student-level data on home background and individual migration histories linked from administrative registers. We find…

  13. Gap solitons in periodic Schrodinger lattice system with nonlinear hopping

    Directory of Open Access Journals (Sweden)

    Ming Cheng

    2016-10-01

    Full Text Available This article concerns the periodic discrete Schrodinger equation with nonlinear hopping on the infinite integer lattice. We obtain the existence of gap solitons by the linking theorem and concentration compactness method together with a periodic approximation technique. In addition, the behavior of such solutions is studied as $\\alpha\\to 0$. Notice that the nonlinear hopping can be sign changing.

  14. Gender Pay Gap in Poland

    OpenAIRE

    Oczki, Jarosław

    2016-01-01

    The aim of the article is to investigate the actual and explained gender pay gaps in Poland in comparison with selected highly developed countries, and to discuss the factors determining wage disparities between men and women. Data from Eurostat EU-SILC and the International Labour Organization were used. The article concludes that the gender pay gap in Poland is relatively small and decreasing, and that estimates of the explained gender pay gap published by the Internationa...

  15. Bridging the Gap

    DEFF Research Database (Denmark)

    Dahlberg, Rasmus

    2016-01-01

    The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresu...... in its final report to the Danish and Swedish transport authorities while drawing upon experiences from two recent comparable cases of infrastructure disruptions: The Champlain Bridge (2009) and the Forth Road Bridge (2015).......The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresund...... Tunnel, approximately 25,000 of them critical to the regional work market. Even though the risk analysis states that the likelihood of a long-term closure (100C days) is very low Danish and Swedish transport authorities have demanded that the infrastructure operator conducts a survey of the preparedness...

  16. Gap junctions and motor behavior

    DEFF Research Database (Denmark)

    Kiehn, Ole; Tresch, Matthew C.

    2002-01-01

    The production of any motor behavior requires coordinated activity in motor neurons and premotor networks. In vertebrates, this coordination is often assumed to take place through chemical synapses. Here we review recent data suggesting that electrical gap-junction coupling plays an important role...... in coordinating and generating motor outputs in embryonic and early postnatal life. Considering the recent demonstration of a prevalent expression of gap-junction proteins and gap-junction structures in the adult mammalian spinal cord, we suggest that neuronal gap-junction coupling might also contribute...... to the production of motor behavior in adult mammals....

  17. Axial gap rotating electrical machine

    Science.gov (United States)

    None

    2016-02-23

    Direct drive rotating electrical machines with axial air gaps are disclosed. In these machines, a rotor ring and stator ring define an axial air gap between them. Sets of gap-maintaining rolling supports bear between the rotor ring and the stator ring at their peripheries to maintain the axial air gap. Also disclosed are wind turbines using these generators, and structures and methods for mounting direct drive rotating electrical generators to the hubs of wind turbines. In particular, the rotor ring of the generator may be carried directly by the hub of a wind turbine to rotate relative to a shaft without being mounted directly to the shaft.

  18. The Gender Gap in Mathematics: Evidence from Low- and Middle-Income Countries. NBER Working Paper No. 18464

    Science.gov (United States)

    Bharadwaj, Prashant; De Giorgi, Giacomo; Hansen, David; Neilson, Christopher

    2012-01-01

    We establish the presence of a gender gap in mathematics across many low- and middle-income countries using detailed, comparable test score data. Examining micro level data on school performance linked to household demographics we note that first, the gender gap appears to increase with age. Indeed, the gap nearly doubles when comparing 4th grade…

  19. Groundwater Discharge of Legacy Nitrogen to River Networks: Linking Regional Groundwater Models to Streambed Groundwater-Surface Water Exchange and Nitrogen Processing

    Science.gov (United States)

    Barclay, J. R.; Helton, A. M.; Briggs, M. A.; Starn, J. J.; Hunt, A.

    2017-12-01

    Despite years of management, excess nitrogen (N) is a pervasive problem in many aquatic ecosystems. More than half of surface water in the United States is derived from groundwater, and widespread N contamination in aquifers from decades of watershed N inputs suggest legacy N discharging from groundwater may contribute to contemporary N pollution problems in surface waters. Legacy N loads to streams and rivers are controlled by both regional scale flow paths and fine-scale processes that drive N transformations, such as groundwater-surface water exchange across steep redox gradients that occur at stream bed interfaces. Adequately incorporating these disparate scales is a challenge, but it is essential to understanding legacy N transport and making informed management decisions. We developed a regional groundwater flow model for the Farmington River, a HUC-8 basin that drains to the Long Island Sound, a coastal estuary that suffers from elevated N loads despite decades of management, to understand broad patterns of regional transport. To evaluate and refine the regional model, we used thermal infrared imagery paired with vertical temperature profiling to estimate groundwater discharge at the streambed interface. We also analyzed discharging groundwater for multiple N species to quantify fine scale patterns of N loading and transformation via denitrification at the streambed interface. Integrating regional and local estimates of groundwater discharge of legacy N to river networks should improve our ability to predict spatiotemporal patterns of legacy N loading to and transformation within surface waters.

  20. Linking Changes in Management and Riparian Physical Functionality to Water Quality and Aquatic Habitat: A Case Study of Maggie Creek, NV

    Science.gov (United States)

    The total maximum daily load (TMDL) process is ineffective and inappropriate for improving stream water quality in the rural areas of the northern Great Basin, and likely in many areas throughout the country. Important pollutants (e.g., sediment and nutrients) come from the stre...

  1. Detection of Poly- and Perfluoroalkyl Substances (PFASs) in U.S. Drinking Water Linked to Industrial Sites, Military Fire Training Areas, and Wastewater Treatment Plants

    Science.gov (United States)

    2016-01-01

    Drinking water contamination with poly- and perfluoroalkyl substances (PFASs) poses risks to the developmental, immune, metabolic, and endocrine health of consumers. We present a spatial analysis of 2013–2015 national drinking water PFAS concentrations from the U.S. Environmental Protection Agency’s (US EPA) third Unregulated Contaminant Monitoring Rule (UCMR3) program. The number of industrial sites that manufacture or use these compounds, the number of military fire training areas, and the number of wastewater treatment plants are all significant predictors of PFAS detection frequencies and concentrations in public water supplies. Among samples with detectable PFAS levels, each additional military site within a watershed’s eight-digit hydrologic unit is associated with a 20% increase in PFHxS, a 10% increase in both PFHpA and PFOA, and a 35% increase in PFOS. The number of civilian airports with personnel trained in the use of aqueous film-forming foams is significantly associated with the detection of PFASs above the minimal reporting level. We find drinking water supplies for 6 million U.S. residents exceed US EPA’s lifetime health advisory (70 ng/L) for PFOS and PFOA. Lower analytical reporting limits and additional sampling of smaller utilities serving PFAS contamination sources. PMID:27752509

  2. Linking land-use type and stream water quality using spatial data of fecal indicator bacteria and heavy metals in the Yeongsan river basin.

    Science.gov (United States)

    Kang, Joo-Hyon; Lee, Seung Won; Cho, Kyung Hwa; Ki, Seo Jin; Cha, Sung Min; Kim, Joon Ha

    2010-07-01

    This study reveals land-use factors that explain stream water quality during wet and dry weather conditions in a large river basin using two different linear models-multiple linear regression (MLR) models and constrained least squares (CLS) models. Six land-use types and three topographical parameters (size, slope, and permeability) of the watershed were incorporated into the models as explanatory variables. The suggested models were then demonstrated using a digitized elevation map in conjunction with the land-use and the measured concentration data for Escherichia coli (EC), Enterococci bacteria (ENT), and six heavy metal species collected monthly during 2007-2008 at 50 monitoring sites in the Yeongsan Watershed, Korea. The results showed that the MLR models can be a powerful tool for predicting the average concentrations of pollutants in stream water (the Nash-Sutcliffe (NS) model efficiency coefficients ranged from 0.67 to 0.95). On the other hand, the CLS models, with moderately good prediction performance (the NS coefficients ranged 0.28-0.85), were more suitable for quantifying contributions of respective land-uses to the stream water quality. The CLS models suggested that industrial and urban land-uses are major contributors to the stream concentrations of EC and ENT, whereas agricultural, industrial, and mining areas were significant sources of many heavy metal species. In addition, the slope, size, and permeability of the watershed were found to be important factors determining the extent of the contribution from each land-use type to the stream water quality. The models proposed in this paper can be considered useful tools for developing land cover guidelines and for prioritizing locations for implementing management practices to maintain stream water quality standard in a large river basin. Copyright 2010 Elsevier Ltd. All rights reserved.

  3. Investigation of Swedish cases reveals an outbreak of cryptosporidiosis at a Norwegian hotel with possible links to in-house water systems

    Science.gov (United States)

    Hajdu, Agnes; Vold, Line; Østmo, Torild A; Helleve, Anna; Helgebostad, Sigrid R; Krogh, Truls; Robertson, Lucy; de Jong, Birgitta; Nygård, Karin

    2008-01-01

    Background In March 2007, the Norwegian Institute of Public Health was notified of Swedish individuals diagnosed with cryptosporidiosis after staying at a Norwegian hotel. In Norway, cryptosporidiosis is not reportable, and human infections are rarely diagnosed. Methods A questionnaire on illness and exposure history was e-mailed to seven organised groups who had visited the hotel in March. Cases were defined as persons with diarrhoea for more than two days or laboratory-confirmed cryptosporidiosis during or within two weeks of the hotel visit. The risk factor analysis was restricted to two groups with the highest attack rates (AR) and same hotel stay period. Local food safety authorities conducted environmental investigations. Results In total, 25 diarrhoeal cases (10 laboratory-confirmed) were identified among 89 respondents. Although environmental samples were negative, epidemiological data suggest an association with in-house water consumption. In one group, the AR was higher amongst consumers of water from hotel dispenser (relative risk [RR] = 3.0; 95% confidence interval [CI]: 0.9–9.8), tap water (RR = 2.3; CI: 0.9–5.8), and lower amongst commercial bottled water drinkers (RR = 0.6; CI: 0.4–1.0). Consumption of ice cubes was a risk-factor (RR = 7.1; CI: 1.1–45.7) in the two groups combined. Conclusion This outbreak would probably have remained undetected without the alert from Swedish health authorities, illustrating the difficulties in outbreak detection due to low health care seeking behaviour for diarrhoea and limited parasite diagnostics in Norway. Awareness of cryptosporidiosis should be raised amongst Norwegian medical personnel to improve case and outbreak detection, and possible risks related to in-house water systems should be assessed. PMID:18976495

  4. Interhemispheric teleconnections: Late Pliocene change in Mediterranean outflow water linked to changes in Indonesian Through-Flow and Atlantic Meridional Overturning Circulation, a review and update

    Science.gov (United States)

    Sarnthein, Michael; Grunert, Patrick; Khélifi, Nabil; Frank, Martin; Nürnberg, Dirk

    2018-03-01

    The ultimate, possibly geodynamic control and potential impact of changes in circulation activity and salt discharge of Mediterranean outflow waters (MOW) on Atlantic meridional overturning circulation have formed long-standing objectives in paleoceanography. Late Pliocene changes in the distal advection of MOW were reconstructed on orbital timescales for northeast Atlantic DSDP/ODP sites 548 and 982 off Brittany and on Rockall Plateau, supplemented by a proximal record from Site U1389 west off Gibraltar, and compared to Western Mediterranean surface and deep-water records of Alboran Sea Site 978. From 3.43 to 3.3 Ma, MOW temperatures and salinities form a prominent rise by 2-4 °C and 3 psu, induced by a preceding and coeval rise in sea surface and deep-water salinity and increased summer aridity in the Mediterranean Sea. We speculate that these changes triggered an increased MOW flow and were ultimately induced by a persistent 2.5 °C cooling of Indonesian Through-Flow waters. The temperature drop resulted from the northward drift of Australia that crossed a threshold value near 3.6-3.3 Ma and led to a large-scale cooling of the eastern subtropical Indian Ocean and in turn, to a reduction of African monsoon rains. Vice versa, we show that the distinct rise in Mediterranean salt export after 3.4 Ma induced a unique long-term rise in the formation of Upper North Atlantic Deep Water, that followed with a phase lag of 100 ky. In summary, we present evidence for an interhemispheric teleconnection of processes in the Indonesian Gateways, the Mediterranean and Labrador Seas, jointly affecting Pliocene climate.

  5. Investigation of Swedish cases reveals an outbreak of cryptosporidiosis at a Norwegian hotel with possible links to in-house water systems

    Directory of Open Access Journals (Sweden)

    Krogh Truls

    2008-11-01

    Full Text Available Abstract Background In March 2007, the Norwegian Institute of Public Health was notified of Swedish individuals diagnosed with cryptosporidiosis after staying at a Norwegian hotel. In Norway, cryptosporidiosis is not reportable, and human infections are rarely diagnosed. Methods A questionnaire on illness and exposure history was e-mailed to seven organised groups who had visited the hotel in March. Cases were defined as persons with diarrhoea for more than two days or laboratory-confirmed cryptosporidiosis during or within two weeks of the hotel visit. The risk factor analysis was restricted to two groups with the highest attack rates (AR and same hotel stay period. Local food safety authorities conducted environmental investigations. Results In total, 25 diarrhoeal cases (10 laboratory-confirmed were identified among 89 respondents. Although environmental samples were negative, epidemiological data suggest an association with in-house water consumption. In one group, the AR was higher amongst consumers of water from hotel dispenser (relative risk [RR] = 3.0; 95% confidence interval [CI]: 0.9–9.8, tap water (RR = 2.3; CI: 0.9–5.8, and lower amongst commercial bottled water drinkers (RR = 0.6; CI: 0.4–1.0. Consumption of ice cubes was a risk-factor (RR = 7.1; CI: 1.1–45.7 in the two groups combined. Conclusion This outbreak would probably have remained undetected without the alert from Swedish health authorities, illustrating the difficulties in outbreak detection due to low health care seeking behaviour for diarrhoea and limited parasite diagnostics in Norway. Awareness of cryptosporidiosis should be raised amongst Norwegian medical personnel to improve case and outbreak detection, and possible risks related to in-house water systems should be assessed.

  6. Investigation of Swedish cases reveals an outbreak of cryptosporidiosis at a Norwegian hotel with possible links to in-house water systems.

    Science.gov (United States)

    Hajdu, Agnes; Vold, Line; Østmo, Torild A; Helleve, Anna; Helgebostad, Sigrid R; Krogh, Truls; Robertson, Lucy; de Jong, Birgitta; Nygård, Karin

    2008-11-01

    In March 2007, the Norwegian Institute of Public Health was notified of Swedish individuals diagnosed with cryptosporidiosis after staying at a Norwegian hotel. In Norway, cryptosporidiosis is not reportable, and human infections are rarely diagnosed. A questionnaire on illness and exposure history was e-mailed to seven organised groups who had visited the hotel in March. Cases were defined as persons with diarrhoea for more than two days or laboratory-confirmed cryptosporidiosis during or within two weeks of the hotel visit. The risk factor analysis was restricted to two groups with the highest attack rates (AR) and same hotel stay period. Local food safety authorities conducted environmental investigations. In total, 25 diarrhoeal cases (10 laboratory-confirmed) were identified among 89 respondents. Although environmental samples were negative, epidemiological data suggest an association with in-house water consumption. In one group, the AR was higher amongst consumers of water from hotel dispenser (relative risk [RR] = 3.0; 95% confidence interval [CI]: 0.9-9.8), tap water (RR = 2.3; CI: 0.9-5.8), and lower amongst commercial bottled water drinkers (RR = 0.6; CI: 0.4-1.0). Consumption of ice cubes was a risk-factor (RR = 7.1; CI: 1.1-45.7) in the two groups combined. This outbreak would probably have remained undetected without the alert from Swedish health authorities, illustrating the difficulties in outbreak detection due to low health care seeking behaviour for diarrhoea and limited parasite diagnostics in Norway. Awareness of cryptosporidiosis should be raised amongst Norwegian medical personnel to improve case and outbreak detection, and possible risks related to in-house water systems should be assessed.

  7. Experimental Study on CHF in a Hemispherical Narrow Gap

    International Nuclear Information System (INIS)

    Jeong, J.H.; Park, R.J.; Kang, K.H.; Kim, S.B.; Kim, H.D.

    1999-01-01

    As a part of the SONATA-IV program, KAERI is conducting an experimental investigation of critical heat flux(CHF) in hemispherical narrow gaps. A visualization experiment, VISU-II, was done as the first step to get a visual observation of the flow behaviour inside a hemispherical gap and to understand the CHF-triggering mechanism. It was observed that the counter-current flow limitation (CCFL) phenomenon prevented water from wetting the heater surface and induced CHF. The CHFG (Critical Heat Flux in Gap) test is now being performed to measure the CHF and to investigate the inherent cooling mechanism in hemispherical narrow gaps. Temperature measurements over the heater surface show that the two-phase flow behaviour inside the gaps could be quite different from the other usual CHF experiments. The measured CHF points are lower than the predictions by existing empirical correlations based on the data measured with small-scale horizontal plates and vertical annulus. (authors)

  8. Bottled Water and Fluoride

    Science.gov (United States)

    ... Private Wells Infant Formula Fluorosis Public Health Service Recommendation Water Operators & Engineers Water Fluoridation Additives Shortages of Fluoridation Additives Drinking Water Pipe Systems CDC-Sponsored Water Fluoridation Training Links to Other ...

  9. Well-Constructed Single-Layer Molybdenum Disulfide Nanorose Cross-Linked by Three Dimensional-Reduced Graphene Oxide Network for Superior Water Splitting and Lithium Storage Property

    Science.gov (United States)

    Zhao, Yanyan; Kuai, Long; Liu, Yanguo; Wang, Pengpeng; Arandiyan, Hamidreza; Cao, Sufeng; Zhang, Jie; Li, Fengyun; Wang, Qing; Geng, Baoyou; Sun, Hongyu

    2015-01-01

    A facile one-step solution reaction route for growth of novel MoS2 nanorose cross-linked by 3D rGO network, in which the MoS2 nanorose is constructed by single-layered or few-layered MoS2 nanosheets, is presented. Due to the 3D assembled hierarchical architecture of the ultrathin MoS2 nanosheets and the interconnection of 3D rGO network, as well as the synergetic effects of MoS2 and rGO, the as-prepared MoS2-NR/rGO nanohybrids delivered high specific capacity, excellent cycling and good rate performance when evaluated as an anode material for lithium-ion batteries. Moreover, the nanohybrids also show excellent hydrogen-evolution catalytic activity and durability in an acidic medium, which is superior to MoS2 nanorose and their nanoparticles counterparts. PMID:25735416

  10. Evaluation of indirect TaSP enzyme-linked immunosorbent assay for diagnosis of tropical theileriosis in cattle (Bos indicus) and water buffaloes (Bubalus bubalis) in Egypt.

    Science.gov (United States)

    Mohamed, Amr M; Abdel-Rady, Ahmed; Ahmed, Laila S; El-Hosary, Amira

    2012-05-25

    The aim of the present study was to evaluate the validity of Theileria annulata surface protein (TaSP)-ELISA, in comparison with traditional microscopic test, for the diagnosis of T. annulata infection among Egyptian baladi cattle (Bos taurus) and water buffaloes (Bubalus bubalis). Molecular confirmation of infection using T. annulata merozoite surface (Tams-1) target amplification by PCR was used as a gold standard. A total of 76 clinically suspected animals including 64 baladi cattle and 12 water buffaloes were investigated in the current study by the three methods. Based on the PCR-confirmed results, the evaluation study revealed higher sensitivity of TaSP-ELISA (72.9% and 75%) as compared to microscopic examination (58.3% and 50%) among cattle and buffaloes, respectively. On the other hand, the specificity of TaSP-ELISA in diagnosis of T. annulata infection was higher (87.5%) in baladi cattle as compared to water buffaloes (37.5%). In conclusion, TaSP-ELISA was shown to be suitable for the diagnosis of T. annulata infection in cattle under field conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Mind the Gap

    Science.gov (United States)

    2008-09-01

    Astronomers have been able to study planet-forming discs around young Sun-like stars in unsurpassed detail, clearly revealing the motion and distribution of the gas in the inner parts of the disc. This result, which possibly implies the presence of giant planets, was made possible by the combination of a very clever method enabled by ESO's Very Large Telescope. Uncovering the disc ESO PR Photo 27a/08 Planet-forming Disc Planets could be home to other forms of life, so the study of exoplanets ranks very high in contemporary astronomy. More than 300 planets are already known to orbit stars other than the Sun, and these new worlds show an amazing diversity in their characteristics. But astronomers don't just look at systems where planets have already formed - they can also get great insights by studying the discs around young stars where planets may currently be forming. "This is like going 4.6 billion years back in time to watch how the planets of our own Solar System formed," says Klaus Pontoppidan from Caltech, who led the research. Pontoppidan and colleagues have analysed three young analogues of our Sun that are each surrounded by a disc of gas and dust from which planets could form. These three discs are just a few million years old and were known to have gaps or holes in them, indicating regions where the dust has been cleared and the possible presence of young planets. The new results not only confirm that gas is present in the gaps in the dust, but also enable astronomers to measure how the gas is distributed in the disc and how the disc is oriented. In regions where the dust appears to have been cleared out, molecular gas is still highly abundant. This can either mean that the dust has clumped together to form planetary embryos, or that a planet has already formed and is in the process of clearing the gas in the disc. For one of the stars, SR 21, a likely explanation is the presence of a massive giant planet orbiting at less than 3.5 times the distance

  12. PhoneGap for enterprise

    CERN Document Server

    Shotts, Kerri

    2014-01-01

    This book is intended for developers who wish to use PhoneGap to develop useful, rich, secure mobile applications for their enterprise environment. The book assumes you have working knowledge of PhoneGap, HTML5, CSS3, and JavaScript, and a reasonable understanding of networking and n-tier architectures.

  13. Tonle Sap Lake Water Storage Change Over 24 Years From Satellite Observation and Its Link With Mekong River Discharge and Climate Events

    Science.gov (United States)

    Biancamaria, S.; Frappart, F.; Normandin, C.; Blarel, F.; Bourrel, L.; Aumont, M.; Azema, P.; Vu, P. L.; Lubac, B.; Darrozes, J.

    2017-12-01

    The Tonle Sap lake is the largest freshwater lake in Southeast Asia and is located within the Mekong basin (mainly in Cambodia). It is one of he most productive ecosystem of the world and provide two thirds of Cambodia fish catch. It also plays a unique role on the Mekong basin hydrological cycle: during the monsoon period, the Mekong river partially flows to the lake, whereas during the dry season, the lake flows to the Mekong delta. It is therefore crucial to monitor and take into account this lake to estimate Mekong discharge to the ocean. However, in situ measurements of lake level and river discharge are very sparse (especially during the last decades) and computing lake storage variation from in situ data only is difficult due to the huge annual variation of lake area. That's why, satellite data (nadir radar altimetry and visible imagery) have been used to study its volume variation and its relationship with climate events and Mekong river discharge. Multi-mission altimetry data have been extracted (Topex, ERS-2, ENVISAT, Jason-1, Jason-2, Saral and Jason-3, using CTOH data extraction tools) to derive a lake water level from1993 to 2016, which varies from 3 m to 12 m. Lake area have been computed from MODIS data from 2000 to 2016 and varies from 3,400 km2 to 11,800 km2. These dataset clearly shows a relationship between lake water level and area, which has been used to estimate lake water volume change from 1995 to 2016, with a minimum in 2015 and a maximum in 2011. Lake's droughts and floods can be observed during moderate and strong El Nino/La Nina events, enhanced by the Pacific Decadal Oscillation. Besides, comparison with in situ discharge at the outlet of the Mekong basin (over 1995/2000 time period) shows that lake water level is 20 days time lagged and increases/decreases after Mekong discharge at its outlet. This time lag results of Mekong river partially flowing to the lake. Finally, high correlation between lake level and outlet discharge allows to

  14. A study on critical heat flux in gap

    International Nuclear Information System (INIS)

    Park, Rae Joon; Jeong, Ji Whan; Cho, Young Ro; Chang, Young Cho; Kang, Kyung Ho; Kim, Jong Whan; Kim, Sang Baik; Kim, Hee Dong

    1999-04-01

    The scope and content of this study is to perform the test on critical heat flux in hemispherical narrow gaps using distilled water and Freon R-113 as experimental parameters, such as system pressure from 1 to 10 atm and gap thickness of 0.5, 1.0, 2.0, and 5.0 mm. The CHFG test results have shown that the measured values of critical power are much lower than the predictions made by empirical CHF correlations applicable to flat plate gaps and annuli. The pressure effect on the critical power was found to be much milder than predictions by those CHF correlations. The values and the pressure trend of the critical powers measured in the present experiments are close to the values converted from the CCFL data. This confirms the claim that a CCFL brings about local dryout and finally, global dryout in hemispherical narrow gaps. Increases in the gap thickness lead to increase in critical power. The measured critical power using R-113 in hemispherical narrow gaps are 60 % lower than that using water due to the lower boiling point, which is different from the pool boiling condition. The CCFL (counter counter flow limit) test facility was constructed and the test is being performed to estimate the CCFL phenomena and to evaluate the CHFG test results on critical power in hemispherical narrow gaps. (Author). 35 refs., 2 tabs., 19 figs

  15. A study on critical heat flux in gap

    Energy Technology Data Exchange (ETDEWEB)

    Park, Rae Joon; Jeong, Ji Whan; Cho, Young Ro; Chang, Young Cho; Kang, Kyung Ho; Kim, Jong Whan; Kim, Sang Baik; Kim, Hee Dong

    1999-04-01

    The scope and content of this study is to perform the test on critical heat flux in hemispherical narrow gaps using distilled water and Freon R-113 as experimental parameters, such as system pressure from 1 to 10 atm and gap thickness of 0.5, 1.0, 2.0, and 5.0 mm. The CHFG test results have shown that the measured values of critical power are much lower than the predictions made by empirical CHF correlations applicable to flat plate gaps and annuli. The pressure effect on the critical power was found to be much milder than predictions by those CHF correlations. The values and the pressure trend of the critical powers measured in the present experiments are close to the values converted from the CCFL data. This confirms the claim that a CCFL brings about local dryout and finally, global dryout in hemispherical narrow gaps. Increases in the gap thickness lead to increase in critical power. The measured critical power using R-113 in hemispherical narrow gaps are 60 % lower than that using water due to the lower boiling point, which is different from the pool boiling condition. The CCFL (counter counter flow limit) test facility was constructed and the test is being performed to estimate the CCFL phenomena and to evaluate the CHFG test results on critical power in hemispherical narrow gaps. (Author). 35 refs., 2 tabs., 19 figs.

  16. Experimental Study on Critical Power in a Hemispherical Narrow Gap

    International Nuclear Information System (INIS)

    Park, Rae-Joon; Ha, Kwang-Soon; Kim, Sang-Baik; Kim, Hee-Dong; Jeong, Ji-Hwan

    2002-01-01

    An experimental study of critical heat flux in gap (CHFG) has been performed to investigate the inherent cooling mechanism in a hemispherical narrow gap. The objectives of the CHFG test are to measure critical power from a critical heat removal rate through the hemispherical narrow gap using distilled water with experimental parameters of system pressure and gap width. The CHFG test results have shown that a countercurrent flow limitation (CCFL) brings about local dryout at the small edge region of the upper part and finally global dryout in a hemispherical narrow gap. Increases in the gap width and pressure lead to an increase in critical power. The measured values of critical power are lower than the predictions made by other empirical CHF correlations applicable to flat plate, annuli, and small spherical gaps. The measured data on critical power in the hemispherical narrow gaps have been correlated using nondimensional parameters with a range of approximately ±20%. The developed correlation has been expanded to apply the spherical geometry using the Siemens/KWU correlation

  17. The fluctuating gap model

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Xiaobin

    2011-01-15

    The quasi-one-dimensional systems exhibit some unusual phenomenon, such as the Peierls instability, the pseudogap phenomena and the absence of a Fermi-Dirac distribution function line shape in the photoemission spectroscopy. Ever since the discovery of materials with highly anisotropic properties, it has been recognized that fluctuations play an important role above the three-dimensional phase transition. This regime where the precursor fluctuations are presented can be described by the so called fluctuating gap model (FGM) which was derived from the Froehlich Hamiltonian to study the low energy physics of the one-dimensional electron-phonon system. Not only is the FGM of great interest in the context of quasi-one-dimensional materials, liquid metal and spin waves above T{sub c} in ferromagnets, but also in the semiclassical approximation of superconductivity, it is possible to replace the original three-dimensional problem by a directional average over effectively one-dimensional problem which in the weak coupling limit is described by the FGM. In this work, we investigate the FGM in a wide temperature range with different statistics of the order parameter fluctuations. We derive a formally exact solution to this problem and calculate the density of states, the spectral function and the optical conductivity. In our calculation, we show that a Dyson singularity appears in the low energy density of states for Gaussian fluctuations in the commensurate case. In the incommensurate case, there is no such kind of singularity, and the zero frequency density of states varies differently as a function of the correlation lengths for different statistics of the order parameter fluctuations. Using the density of states we calculated with non-Gaussian order parameter fluctuations, we are able to calculate the static spin susceptibility which agrees with the experimental data very well. In the calculation of the spectral functions, we show that as the correlation increases, the

  18. The fluctuating gap model

    International Nuclear Information System (INIS)

    Cao, Xiaobin

    2011-01-01

    The quasi-one-dimensional systems exhibit some unusual phenomenon, such as the Peierls instability, the pseudogap phenomena and the absence of a Fermi-Dirac distribution function line shape in the photoemission spectroscopy. Ever since the discovery of materials with highly anisotropic properties, it has been recognized that fluctuations play an important role above the three-dimensional phase transition. This regime where the precursor fluctuations are presented can be described by the so called fluctuating gap model (FGM) which was derived from the Froehlich Hamiltonian to study the low energy physics of the one-dimensional electron-phonon system. Not only is the FGM of great interest in the context of quasi-one-dimensional materials, liquid metal and spin waves above T c in ferromagnets, but also in the semiclassical approximation of superconductivity, it is possible to replace the original three-dimensional problem by a directional average over effectively one-dimensional problem which in the weak coupling limit is described by the FGM. In this work, we investigate the FGM in a wide temperature range with different statistics of the order parameter fluctuations. We derive a formally exact solution to this problem and calculate the density of states, the spectral function and the optical conductivity. In our calculation, we show that a Dyson singularity appears in the low energy density of states for Gaussian fluctuations in the commensurate case. In the incommensurate case, there is no such kind of singularity, and the zero frequency density of states varies differently as a function of the correlation lengths for different statistics of the order parameter fluctuations. Using the density of states we calculated with non-Gaussian order parameter fluctuations, we are able to calculate the static spin susceptibility which agrees with the experimental data very well. In the calculation of the spectral functions, we show that as the correlation increases, the quasi

  19. Bridging the terahertz gap

    International Nuclear Information System (INIS)

    Davies, Giles; Linfield, Edmund

    2004-01-01

    Over the last century or so, physicists and engineers have progressively explored and conquered the electromagnetic spectrum. Starting with visible light, we have encroached outwards, developing techniques for generating and detecting radiation at both higher and lower frequencies. And as each successive region of the spectrum has been colonized, we have developed technology to exploit the radiation found there. X-rays, for example, are routinely used to image hidden objects. Near-infrared radiation is used in fibre-optic communications and in compact-disc players, while microwaves are used to transmit signals from your mobile phone. But there is one part of the electromagnetic spectrum that has steadfastly resisted our advances. This is the terahertz region, which ranges from frequencies of about 300 GHz to 10 THz (10 x 10 sup 1 sup 2 Hz). This corresponds to wavelengths of between about 1 and 0.03 mm, and lies between the microwave and infrared regions of the spectrum. However, the difficulties involved in making suitably compact terahertz sources and detectors has meant that this region of the spectrum has only begun to be explored thoroughly over the last decade. A particularly intriguing feature of terahertz radiation is that the semiconductor devices that generate radiation at frequencies above and below this range operate in completely different ways. At lower frequencies, microwaves and millimetre- waves can be generated by 'electronic' devices such as those found in mobile phones. At higher frequencies, near-infrared and visible light are generated by 'optical' devices such as semiconductor laser diodes, in which electrons emit light when they jump across the semiconductor band gap. Unfortunately, neither electronic nor optical devices can conveniently be made to work in the terahertz region because the terahertz frequency range sits between the electronic and optical regions of the electromagnetic spectrum. Developing a terahertz source is therefore a

  20. Growth, water use efficiency, and adaptive features of the tree legume tagasaste (Chamaecytisus proliferus Link.) on deep sands in south-western Australia

    International Nuclear Information System (INIS)

    Lefroy, E. C.; Pate, J. S.

    2001-01-01

    Four-year-old tagasaste trees in dense plantation and wide-spaced alley cropping layouts at Moora, Western Australia, were cut back to 0.6 m high and their patterns of coppice regrowth and water use monitored over 3 years. Trees reached a permanent fresh watertable at 5 m depth by means of deeply penetrating sinker roots. Dry matter (DM) accumulation and transpiration loss were closely similar at the 2 planting densities despite higher soil water contents in alley plots. Yearly transpiration at plantation density amounted to 0.55 and 0.63 of Penman-Montieth potential evapotranspiration (E 0 ) in the second and third years, respectively. Mean water use efficiency over the 3 years was 247 L/kg DM, compared with values in the range 186-320 L/kg for younger pot-and column-grown trees. Using a combination of neutron moisture metre (NMM) assays of soil moisture and deuterium: hydrogen ratios of groundwater and xylem water of tagasaste and annual weeds, it was shown that trees became increasingly dependent on groundwater over time and had the capacity to switch rapidly between soil and groundwater sources. Seasonal changes in carbon isotope composition of new shoot tip dry matter indicated that plantation trees were less stressed than alley trees by the third summer as they adapted to heavy dependence on groundwater. In the third season, when plantation trees were transpiring at rates equivalent to 2.3 times annual rainfall, NMM profiles and time domain reflectometry (TDR) assays indicated that no free drainage occurred and that trees were capable of hydraulically lifting groundwater to near surface soil in the dry season. Additional adaptive features of importance to this environment included heat stress induced leaf shedding, development of perennial root nodules on lower parts of tap roots, and an ability to respond in summer to artificial irrigation or a seasonal rainfall by rapidly increasing transpiration 2-3-fold to values equalling E 0 . Copyright (2001) CSIRO

  1. Cooperative protein structural dynamics of homodimeric hemoglobin linked to water cluster at subunit interface revealed by time-resolved X-ray solution scattering

    Directory of Open Access Journals (Sweden)

    Jong Goo Kim

    2016-03-01

    Full Text Available Homodimeric hemoglobin (HbI consisting of two subunits is a good model system for investigating the allosteric structural transition as it exhibits cooperativity in ligand binding. In this work, as an effort to extend our previous study on wild-type and F97Y mutant HbI, we investigate structural dynamics of a mutant HbI in solution to examine the role of well-organized interfacial water cluster, which has been known to mediate intersubunit communication in HbI. In the T72V mutant of HbI, the interfacial water cluster in the T state is perturbed due to the lack of Thr72, resulting in two less interfacial water molecules than in wild-type HbI. By performing picosecond time-resolved X-ray solution scattering experiment and kinetic analysis on the T72V mutant, we identify three structurally distinct intermediates (I1, I2, and I3 and show that the kinetics of the T72V mutant are well described by the same kinetic model used for wild-type and F97Y HbI, which involves biphasic kinetics, geminate recombination, and bimolecular CO recombination. The optimized kinetic model shows that the R-T transition and bimolecular CO recombination are faster in the T72V mutant than in the wild type. From structural analysis using species-associated difference scattering curves for the intermediates, we find that the T-like deoxy I3 intermediate in solution has a different structure from deoxy HbI in crystal. In addition, we extract detailed structural parameters of the intermediates such as E-F distance, intersubunit rotation angle, and heme-heme distance. By comparing the structures of protein intermediates in wild-type HbI and the T72V mutant, we reveal how the perturbation in the interfacial water cluster affects the kinetics and structures of reaction intermediates of HbI.

  2. The test of Tensile Properties and Water Resistance of a Novel Cross-linked Starch Prepared by Adding Oil-Flax

    Science.gov (United States)

    Shi, Dawei; Wang, Rui

    2017-12-01

    In this study, to solve the poor water resistance and the low mechanical properties of starch, a mixed-starch composite matrix which including glycerol, sorbitol, and urea, were prepared via single-crew extrusion, then adding oil-flax to improve its physical mechanical and used to a source of biodegradable plastics material. The composite matrix was systematically characterized using various analytic tools including XRD, SEM and TG. The composite showed a maximum tensile strength of 18.11Mpa and moisture absorption 17.67%, while the original starch matrix was only 12.51 Mpa and 24.98%, respectively.

  3. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers

    DEFF Research Database (Denmark)

    Kirkeskov, Lilli; Kristiansen, Eva; Bøggild, Henrik

    2010-01-01

    with data on dental caries from the Danish National Board of Health database on child dental health for 5-year-old children born in 1989 and 1999, and for 15-year-old children born in 1979 and 1989. The number of children included in the cohorts varied between 41.000 and 48.000. Logistic regression was used...... if analysis was limited to children residing in the same place during the entire study period. Conclusions: The study confirmed previous findings of an inverse relation between fluoride concentration in the drinking water and dental caries in children. This correlation was found in spite of the extensive use...

  4. Study on optimal conditions and adsorption kinetics of copper from water by collodion membrane cross-linked poly-γ-glutamic acid

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xiangting; Wang, Aiyin; Li, Guoxing; Dong, Xinjiao; Wu, Mingjiang [Wenzhou University, Wenzhou (China); Zheng, Xiaojie [Wenzhou Vocational College of Technology and Science, Wenzhou (China)

    2013-06-15

    Poly-γ-glutamic acid (γ-PGA) is a novel polyamino acid formed through microorganism fermentation and biosynthesis. In the present test, membrane (PGA-C) formation by γ-PGA and collodion was performed by using 0.1% glutaraldehyde as a cross-linking agent. A study was conducted on the PGA-C adsorption of Cu{sup 2+}, specifically the related adsorption equilibrium and kinetics, desorption and regeneration. The results show that with an initial solution pH=5.5 and at 318 K, the static adsorption isotherm behavior of PGA-C is in compliance with the Langmuir model and is beneficial to the adsorption of the metal. Meanwhile, with the reaction lasting for 30min, adsorption equilibrium was reached with a maximum adsorption capacity up to 7.431 mg/g. The entire reaction process follows the pseudo-second-order kinetics. By using PGA-C, good regeneration results were obtained after adsorption-generation-adsorption cycling with an HCl solution (0.1 mol/L) as regeneration liquid.

  5. Use of γ-irradiation cross-linking to improve the water vapor permeability and the chemical stability of milk protein films

    International Nuclear Information System (INIS)

    Ouattara, B.; Canh, L.T.; Vachon, C.; Mateescu, M.A.; Lacroix, M.

    2002-01-01

    γ-irradiation was used to produce free-standing cross-linked milk proteins. Film forming solutions were prepared according to a method previously developed in our laboratory using calcium caseinate (cas) with various proportions of whey protein isolate (wpi) or whey protein concentrate (wpc). The following caseinate-whey protein (cas:wp) ratio were prepared: 100:0, 75:25, 50:50, 25:75, and 0:100. The WVP of the films was determined gravimetrically at 23 deg. C using a modified ASTM procedure. Molecular properties characterization was performed by size exclusion chromatography (SEC). Results showed significant (p≤0.05) reduction of the WVP of protein films for the following formulations: cas:wpi or cas:wpc (100:0); cas:wpi (25:75); cas:wpc (25:75); and cas:wpc (0:100). Mixture of cas and wpi produced a synergistic effect. The strongest combined effect was obtained for cas:wpi (25:75) formulation with permeability values of 2.07 and 1.38 g mm/m 2 d mm Hg for unirradiated and irradiated samples, respectively. γ-irradiation also induced a substantial increase of high molecular weight protein components in film forming solutions. The predominant fraction was ≥10x10 6 Da for irradiated film forming solutions, compared to less than 0.2x10 6 Da for native unirradiated solutions

  6. Use of {gamma}-irradiation cross-linking to improve the water vapor permeability and the chemical stability of milk protein films

    Energy Technology Data Exchange (ETDEWEB)

    Ouattara, B.; Canh, L.T.; Vachon, C.; Mateescu, M.A.; Lacroix, M. E-mail: monique.lacroix@inrs-iaf.uquebec.ca

    2002-03-01

    {gamma}-irradiation was used to produce free-standing cross-linked milk proteins. Film forming solutions were prepared according to a method previously developed in our laboratory using calcium caseinate (cas) with various proportions of whey protein isolate (wpi) or whey protein concentrate (wpc). The following caseinate-whey protein (cas:wp) ratio were prepared: 100:0, 75:25, 50:50, 25:75, and 0:100. The WVP of the films was determined gravimetrically at 23 deg. C using a modified ASTM procedure. Molecular properties characterization was performed by size exclusion chromatography (SEC). Results showed significant (p{<=}0.05) reduction of the WVP of protein films for the following formulations: cas:wpi or cas:wpc (100:0); cas:wpi (25:75); cas:wpc (25:75); and cas:wpc (0:100). Mixture of cas and wpi produced a synergistic effect. The strongest combined effect was obtained for cas:wpi (25:75) formulation with permeability values of 2.07 and 1.38 g mm/m{sup 2} d mm Hg for unirradiated and irradiated samples, respectively. {gamma}-irradiation also induced a substantial increase of high molecular weight protein components in film forming solutions. The predominant fraction was {>=}10x10{sup 6} Da for irradiated film forming solutions, compared to less than 0.2x10{sup 6} Da for native unirradiated solutions.

  7. El Niño-Southern Oscillation and water resources in the headwaters region of the Yellow River: links and potential for forecasting

    Directory of Open Access Journals (Sweden)

    A. Lü

    2011-04-01

    Full Text Available This research explores the rainfall-El Niño-Southern Oscillation (ENSO and runoff-ENSO relationships and examines the potential for water resource forecasting using these relationships. The Southern Oscillation Index (SOI, Niño1.2, Niño3, Niño4, and Niño3.4 were selected as ENSO indicators for cross-correlation analyses of precipitation and runoff. There was a significant correlation (95% confidence level between precipitation and ENSO indicators during three periods: January, March, and from September to November. In addition, monthly streamflow and monthly ENSO indictors were significantly correlated during three periods: from January to March, June, and from October to December (OND, with lag periods between one and twelve months. Because ENSO events can be accurately predicted one to two years in advance using physical modeling of the coupled ocean-atmosphere system, the lead time for forecasting runoff using ENSO indicators in the Headwaters Region of the Yellow River could extend from one to 36 months. Therefore, ENSO may have potential as a powerful forecasting tool for water resources in the headwater regions of Yellow River.

  8. Linking ecosystem scale vegetation change to shifts in carbon and water cycling: the consequences of widespread piñon mortality in the Southwest

    Energy Technology Data Exchange (ETDEWEB)

    Litvak, Marcy Ellen [University of New Mexico

    2012-10-01

    The southwestern United States experienced an extended drought from 1999-2002 which led to widespread coniferous tree mortality. Piñon-juniper (PJ) woodlands, which occupy 24 million ha throughout the Southwest, were extremely vulnerable to this drought. An abrupt die-off of 40 to 95% of piñon pine (Pinus edulis) and 2-25% of juniper (Juniperus monosperma) across 1.5 million ha triggered rapid and extensive changes in the structure of PJ woodlands with potentially large, yet unknown, consequences for ecosystem services and feedbacks between the carbon cycle and climate system. Given the spatial extent of PJ woodlands (3rd largest biome in the US) and climatic predictions of increased frequency and intensity of drought in the region, it is crucial to understand the consequences of these disturbances on regional carbon and energy dynamics, biogeochemical processes and atmospheric CO2. The overall objective of our research was to quantify what impact widespread mortality of piñon trees has for carbon and water cycling in PJ woodlands. Our specific objectives for this proposal were: 1) Quantify the carbon, water and energy exchange trajectory after mortality in PJ woodlands; 2) Determine the mechanisms controlling the response and recovery of ecosystem production and respiration processes following large-scale piñon mortality; 3) Use the relationships we measure between ecosystem structure and function PJ woodlands recover from mortality to scale the results of our study up to the regional scale.

  9. Linking Species Traits to the Abiotic Template of Flowing Waters: Contrasting Eco physiologies Underlie Displacement of Zebra Mussels by Quagga Mussels in a Large River-Estuary

    Science.gov (United States)

    Casper, A. F.

    2005-05-01

    The St. Lawrence River-Estuary was the gateway of entry for dreissenids to North America and holds some of the oldest populations. The St. Lawrence also has four distinct physical-chemical water masses (a regional scale abiotic template) that both species inhabit. Despite their ecological similarities, quagga mussels are supplanting zebra mussels in much of their shared range. In order to try to better understand the changing distributions of these two species we compared glycogen, shell mass and tissue biomass in each of the water masses. This comparative physiological combined with experimental approaches (estuarine salinity experiments and reciprocal transplants) showed that while quagga mussels should dominate in most habitats, that abiotic/bioenergetic constraints in two regions (the Ottawa River plume and the freshwater-marine transition zone) might prevent them from dominating these locations. These findings are an example of how the interaction of landscape scale abiotic heterogeneity and a species-specific physiology can have strong impacts of distribution of biota large rivers.

  10. Exploring the Links in Monthly to Decadal Variability of the Atmospheric Water Balance Over the Wettest Regions in ERA-20C

    Science.gov (United States)

    Nogueira, M.

    2017-10-01

    Monthly-to-decadal variability of the regional precipitation over Intertropical Convergence Zone and north-Atlantic and north-Pacific storm tracks was investigated using ERA-20C reanalysis. Satellite-based precipitation (P) and evaporation (E) climatological patterns were well reproduced by ERA-20C. Regional P and E monthly time series displayed 20% differences, but these decreased rapidly with time scale ( 10% at yearly time scales). Spectral analysis showed good scale-by-scale statistical agreement between ERA-20C and observations. Using ERA-Interim showed no improvement despite the much wider range of information assimilated (including satellites). Remarkably high Detrended Cross-Correlation Analysis coefficients (ρDCCA > 0.7 and often ρDCCA > 0.9) revealed tight links between the nonperiodic variability of P, moisture divergence (DIV), and pressure velocity (ω) at monthly-to-decadal time scales over all the wet regions. In contrast, ρDCCA was essentially nonsignificant between nonperiodic P and E or sea surface temperature (SST). Thus, the nonperiodic monthly-to-decadal variability of precipitation in these regions is almost fully controlled by dynamics and not by local E or SST (suggested by Clausius-Clapeyron relation). Analysis of regional nonperiodic standard deviations and power spectra (and respective spectral exponents, β) provided further robustness to this conclusion. Finally, clear transitions in β for P, DIV, and ω between tropical and storm track regions were found. The latter is dominated by transient storms, with energy accumulation at synoptic scales and β β values (0.2 to 0.4) were found in the tropics, implying longer-range autocorrelations and slower decreasing variability and information creation with time scale, consistent with the important forcing from internal modes of variability (e.g., El Niño-Southern Oscillation).

  11. The generaltion gap in nursing

    Directory of Open Access Journals (Sweden)

    J.G.P. van Niekerk

    1984-09-01

    Full Text Available Generation gap is one of those catch phrases that we so often use, and misuse, to excuse ourselves or to cover up for our shortcomings. It is like the shortage of nurses behind which we hide from all our nursing problems. Although it is such a commonly used phrase, do we really know what it means? When you consult the Oxford Dictionary, you will find that it defines generation gap as: differences of opinion between those of different generations. It will surprise most people that the generation gap becomes a problem only when there are differences of opinion.

  12. Wide gap semiconductor microwave devices

    International Nuclear Information System (INIS)

    Buniatyan, V V; Aroutiounian, V M

    2007-01-01

    A review of properties of wide gap semiconductor materials such as diamond, diamond-like carbon films, SiC, GaP, GaN and AlGaN/GaN that are relevant to electronic, optoelectronic and microwave applications is presented. We discuss the latest situation and perspectives based on experimental and theoretical results obtained for wide gap semiconductor devices. Parameters are taken from the literature and from some of our theoretical works. The correspondence between theoretical results and parameters of devices is critically analysed. (review article)

  13. Linking Land Use Changes to Surface Water Quality Variability in Lake Victoria: Some Insights From Remote Sensing (GC41B-1101)

    Science.gov (United States)

    Limaye, Ashutosh; Mugo, Robinson; Wanjohi, James; Farah, Hussein; Wahome, Anastasia; Flores, Africa; Irwin, Dan

    2016-01-01

    Various land use changes driven by urbanization, conversion of grasslands and woodlands into farmlands, intensification of agricultural practices, deforestation, land fragmentation and degradation are taking place in Africa. In Kenya, agriculture is the main driver of land use conversions. The impacts of these land use changes are observable in land cover maps, and eventually in the hydrological systems. Reduction or change of natural vegetation cover types increases the speed of surface runoff and reduces water and nutrient retention capacities. This can lead to high nutrient inputs into lakes, resulting in eutrophication, siltation and infestation of floating aquatic vegetation. To assess if changes in land use could be contributing to increased phytoplankton blooms and sediment loads into Lake Victoria, we analyzed land use land cover data from Landsat, as well as surface chlorophyll-a and total suspended matter from MODIS-Aqua sensor.

  14. Linking hydrogen-mediated boron toxicity tolerance with improvement of root elongation, water status and reactive oxygen species balance: a case study for rice.

    Science.gov (United States)

    Wang, Yu; Duan, Xingliang; Xu, Sheng; Wang, Ren; Ouyang, Zhaozeng; Shen, Wenbiao

    2016-12-01

    Boron is essential for plant growth but hazardous when present in excess. As the antioxidant properties of hydrogen gas (H 2 ) were recently described in plants, oxidative stress induced by excess boron was investigated along with other biological responses during rice (Oryza sativa) seed germination to study the beneficial role of H 2 METHODS: Rice seeds were pretreated with exogenous H 2 Using physiological, pharmacological and molecular approaches, the production of endogenous H 2 , growth status, reactive oxygen species (ROS) balance and relative gene expression in rice were measured under boron stress to investigate mechanisms of H 2 -mediated boron toxicity tolerance. In our test, boron-inhibited seed germination and seedling growth, and endogenous H 2 production, were obviously blocked by exogenously applying H 2 The re-establishment of ROS balance was confirmed by reduced lipid peroxidation and ROS accumulation. Meanwhile, activities of catalase (CAT) and peroxidase (POX) were increased. Suppression of pectin methylesterase (PME) activity and downregulation of PME transcripts by H 2 were consistent with the alleviation of root growth inhibition caused by boron. Water status was improved as well. This result was confirmed by the upregulation of genes encoding specific aquaporins (AQPs), the maintenance of low osmotic potential and high content of soluble sugar. Increased transcription of representative AQP genes (PIP2;7 in particular) and BOR2 along with decreased BOR1 mRNA may contribute to lowering boron accumulation. Hydrogen provides boron toxicity tolerance mainly by improving root elongation, water status and ROS balance. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Gap Junctions and Cancer: Communicating for 50 Years’

    Science.gov (United States)

    Aasen, Trond; Mesnil, Marc; Naus, Christian C.; Lampe, Paul D.; Laird, Dale W.

    2017-01-01

    Fifty years ago, tumour cells were found to lack electrical coupling, leading to the hypothesis that loss of direct intercellular communication is commonly associated with cancer onset and progression. Subsequent studies linked this phenomenon to gap junctions composed of connexin proteins. While many studies support the notion that connexins are tumour suppressors, recent evidence suggests that, in some tumour types, they may facilitate specific stages of tumour progression through both junctional and non-junctional signalling pathways. This Timeline article highlights the milestones connecting gap junctions to cancer, and underscores important unanswered questions, controversies and therapeutic opportunities in the field. PMID:27782134

  16. Closing the Cybersecurity Skills Gap

    Directory of Open Access Journals (Sweden)

    Rebecca Vogel

    2016-05-01

    Full Text Available The current consensus is that there is a worldwide gap in skills needed for a competent cybersecurity workforce. This skills gap has implications for the national security sector, both public and private. Although the view is that this will take a concerted effort to rectify, it presents an opportunity for IT professionals, university students, and aspirants to take-up jobs in national security national intelligence as well military and law enforcement intelligence. This paper examines context of the issue, the nature of the cybersecurity skills gap, and some key responses by governments to address the problem. The paper also examines the emerging employment trends, some of the employment challenges, and what these might mean for practice. The paper argues that the imperative is to close the cyber skills gap by taking advantage of the window of opportunity, allowing individuals interested in moving into the cybersecurity field to do so via education and training.

  17. Gap Surface Plasmon Waveguide Analysis

    DEFF Research Database (Denmark)

    Nielsen, Michael Grøndahl; Bozhevolnyi, Sergey I.

    2014-01-01

    Plasmonic waveguides supporting gap surface plasmons (GSPs) localized in a dielectric spacer between metal films are investigated numerically and the waveguiding properties at telecommunication wavelengths are presented. Especially, we emphasize that the mode confinement can advantageously...

  18. Linking phytoplankton nitrogen uptake, macronutrients and chlorophyll- a in SW Atlantic waters: The case of the Gulf of San Jorge, Argentina

    Science.gov (United States)

    Paparazzo, Flavio E.; Williams, Gabriela N.; Pisoni, Juan P.; Solís, Miriam; Esteves, José L.; Varela, Diana E.

    2017-08-01

    We compared biological and chemical parameters in surface waters of the Gulf of San Jorge to better understand carbon export and the factors that control phytoplankton production in an area of the Argentinian Continental Shelf, a vastly under sampled region of the SW Atlantic Ocean. In April of 2012, we estimated new and regenerated primary production in the Gulf by measuring nitrate and ammonium uptake, respectively. We also measured macronutrient, and in situ chlorophyll-a concentrations, which were compared to chlorophyll-a estimates from remote sensing. Although the Gulf of San Jorge presents high levels of chlorophyll-a and primary production, the relationship between these parameters is not straightforward. Previous studies showed that surface chlorophyll-a explains only part of the variance in euphotic-zone integrated primary production, and that satellite-derived chlorophyll-a underestimates in situ primary production. Our results showed large spatial variability in the Gulf, with transitional physico-chemical conditions, such as fronts, that could favor an increase in biological production. In situ chlorophyll-a concentrations were highest at the mid-shelf station (6.0 mg m- 3) and lowest at the northernmost location by an order of magnitude. Remote sensing measurements of chlorophyll-a underestimated our in situ chlorophyll-a concentrations. Total nitrogen (nitrate + ammonium) uptake showed relatively similar rates throughout the study area (≈ 130 nM-N d- 1), except in the northernmost station where it was much lower (53 nM-N d- 1). This north region had a distinct water mass and maximal levels of macronutrients (nitrate ≈ 6 μM, ammonium ≈ 1.2 μM, phosphate ≈ 1.2 μM and silicic acid ≈ 4 μM). For the entire sampling region, chlorophyll-a concentrations strongly correlated with total nitrogen uptake (r = 0.76, n = 8, p < 0.05) and new primary production (r = 0.78, n = 8, p < 0.05). Values of the f-ratio were 0.9 in mid-shelf, and ranged

  19. Understanding the carbon dioxide gaps.

    Science.gov (United States)

    Scheeren, Thomas W L; Wicke, Jannis N; Teboul, Jean-Louis

    2018-06-01

    The current review attempts to demonstrate the value of several forms of carbon dioxide (CO2) gaps in resuscitation of the critically ill patient as monitor for the adequacy of the circulation, as target for fluid resuscitation and also as predictor for outcome. Fluid resuscitation is one of the key treatments in many intensive care patients. It remains a challenge in daily practice as both a shortage and an overload in intravascular volume are potentially harmful. Many different approaches have been developed for use as target of fluid resuscitation. CO2 gaps can be used as surrogate for the adequacy of cardiac output (CO) and as marker for tissue perfusion and are therefore a potential target for resuscitation. CO2 gaps are easily measured via point-of-care analysers. We shed light on its potential use as nowadays it is not widely used in clinical practice despite its potential. Many studies were conducted on partial CO2 pressure differences or CO2 content (cCO2) differences either alone, or in combination with other markers for outcome or resuscitation adequacy. Furthermore, some studies deal with CO2 gap to O2 gap ratios as target for goal-directed fluid therapy or as marker for outcome. CO2 gap is a sensitive marker of tissue hypoperfusion, with added value over traditional markers of tissue hypoxia in situations in which an oxygen diffusion barrier exists such as in tissue oedema and impaired microcirculation. Venous-to-arterial cCO2 or partial pressure gaps can be used to evaluate whether attempts to increase CO should be made. Considering the potential of the several forms of CO2 measurements and its ease of use via point-of-care analysers, it is recommendable to implement CO2 gaps in standard clinical practice.

  20. Colour reconnections and rapidity gaps

    International Nuclear Information System (INIS)

    Loennblad, Leif

    1996-01-01

    I argue that the success of recently proposed models describing events with large rapidity gaps in DIS at HERA in terms of non-perturbative colour exchange is heavily reliant on suppression of perturbative gluon emission in the proton direction. There is little or no physical motivation for such suppression and I show that a model without this suppression cannot describe the rapidity gap events at HERA. (author)

  1. Bridging the Gap (BRIEFING CHARTS)

    Science.gov (United States)

    2007-03-05

    1 Defense Advanced Research Projects Agency “Bridging the Gap ” Dr. Robert F. Leheny Deputy Director Report Documentation Page Form ApprovedOMB No...comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to...4. TITLE AND SUBTITLE Bridging the Gap 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  2. Synthesis of Cross-Linked Chitosan and Application to Adsorption and Speciation of Se (VI and Se (IV in Environmental Water Samples by Inductively Coupled Plasma Optical Emission Spectrometry

    Directory of Open Access Journals (Sweden)

    Yang Bai

    2011-06-01

    Full Text Available A new type of cross-linked chitosan was synthesized with Diethylene Triamine (DCCTS. The adsorption of Se (VI on DCCTS was studied. The effect factors on adsorption and the adsorption mechanism were considered. The results indicated that the DCCTS could concentrate and separate Se (IV at pH = 3.6; the maximum adsorption efficiency was 94%, the adsorption equilibrium time was 30 min; the maximum adsorption capacity was 42.7 mg/g; the adsorption fitted Langmuir equation. A novel method for speciation of Se (VI and Se (IV in environmental water samples has been developed using DCCTS as adsorbent and ICP–OES as determination means. The detection limit of this method was 12 ng/L, the relatively standard deviation was 4.5% and the recovery was 99%~104%.

  3. Dragonfly Mercury Project—A citizen science driven approach to linking surface-water chemistry and landscape characteristics to biosentinels on a national scale

    Science.gov (United States)

    Eagles-Smith, Collin A.; Nelson, Sarah J.; Willacker,, James J.; Flanagan Pritz, Colleen M.; Krabbenhoft, David P.

    2016-02-29

    Mercury is a globally distributed pollutant that threatens human and ecosystem health. Even protected areas, such as national parks, are subjected to mercury contamination because it is delivered through atmospheric deposition, often after long-range transport. In aquatic ecosystems, certain environmental conditions can promote microbial processes that convert inorganic mercury to an organic form (methylmercury). Methylmercury biomagnifies through food webs and is a potent neurotoxicant and endocrine disruptor. The U.S. Geological Survey (USGS), the University of Maine, and the National Park Service (NPS) Air Resources Division are working in partnership at more than 50 national parks across the United States, and with citizen scientists as key participants in data collection, to develop dragonfly nymphs as biosentinels for mercury in aquatic food webs. To validate the use of these biosentinels, and gain a better understanding of the connection between biotic and abiotic pools of mercury, this project also includes collection of landscape data and surface-water chemistry including mercury, methylmercury, pH, sulfate, and dissolved organic carbon and sediment mercury concentration. Because of the wide geographic scope of the research, the project also provides a nationwide “snapshot” of mercury in primarily undeveloped watersheds.

  4. Results of gap conductance tests in the power burst facility

    International Nuclear Information System (INIS)

    Garner, R.W.; Sparks, D.T.

    1977-01-01

    Light water reactor (LWR) fuel rod behavior studies are being conducted by the Thermal Fuels Behavior Program of EG and G Idaho, Inc. These studies are being performed under contract to the Energy Research and Development Adminstration at the Idaho National Engineering Laboratory (INEL), as part of the Nuclear Regulatory Commission's Water Reactor Safety Research Fuel Behavior Program. Experimental data for verification of analytical models developed to predict light water nuclear fuel rod behavior under normal and postulated accident conditions are being obtained from a variety of in-reactor and out-of-reactor experiments. This paper summarizes the results of tests performed in the Power Burst Facility (PBF) to obtain data from which the thermal response, gap conductance, and stored energy of LWR fuel rods can be determined. Primary objectives of the PBF gap conductance test program are (a) to obtain data on a variety of pressurized water reactor (PWR) and boiling water reactor (BWR) fuel rod designs, under a wide range of operating conditions, from which gap conductance values can be determined and (b) to evaluate experimentally the power oscillation method for measuring the gap conductance and thermal response of a fresh or burned LWR fuel rod. Tests have been performed with both irradiated and unirradiated PWR-type fuel and with fresh BWR-type fuel rods. Some PWR rod test results are described, and the thermal response data from BWR rod tests are discussed in greater detail. Comparisons are made of gap conductance values determined by the tests with analytically calculated values using the Fuel Rod Analysis Program-Transient (FRAP-T) computer code. These comparisons provide insight into both the experimental measurements methods and the validity of the gap conductance models

  5. GAP junctional communication in brain secondary organizers.

    Science.gov (United States)

    Bosone, Camilla; Andreu, Abraham; Echevarria, Diego

    2016-06-01

    Gap junctions (GJs) are integral membrane proteins that enable the direct cytoplasmic exchange of ions and low molecular weight metabolites between adjacent cells. They are formed by the apposition of two connexons belonging to adjacent cells. Each connexon is formed by six proteins, named connexins (Cxs). Current evidence suggests that gap junctions play an important part in ensuring normal embryo development. Mutations in connexin genes have been linked to a variety of human diseases, although the precise role and the cell biological mechanisms of their action remain almost unknown. Among the big family of Cxs, several are expressed in nervous tissue but just a few are expressed in the anterior neural tube of vertebrates. Many efforts have been made to elucidate the molecular bases of Cxs cell biology and how they influence the morphogenetic signal activity produced by brain signaling centers. These centers, orchestrated by transcription factors and morphogenes determine the axial patterning of the mammalian brain during its specification and regionalization. The present review revisits the findings of GJ composed by Cx43 and Cx36 in neural tube patterning and discuss Cx43 putative enrollment in the control of Fgf8 signal activity coming from the well known secondary organizer, the isthmic organizer. © 2016 The Authors. Development, Growth & Differentiation published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Developmental Biologists.

  6. Optimal balance of water use efficiency and leaf construction cost with a link to the drought threshold of the desert steppe ecotone in northern China.

    Science.gov (United States)

    Wei, Haixia; Luo, Tianxiang; Wu, Bo

    2016-09-01

    In arid environments, a high nitrogen content per leaf area (Narea) induced by drought can enhance water use efficiency (WUE) of photosynthesis, but may also lead to high leaf construction cost (CC). Our aim was to investigate how maximizing Narea could balance WUE and CC in an arid-adapted, widespread species along a rainfall gradient, and how such a process may be related to the drought threshold of the desert-steppe ecotone in northern China. Along rainfall gradients with a moisture index (MI) of 0·17-0·41 in northern China and the northern Tibetan Plateau, we measured leaf traits and stand variables including specific leaf area (SLA), nitrogen content relative to leaf mass and area (Nmass, Narea) and construction cost (CCmass, CCarea), δ(13)C (indicator of WUE), leaf area index (LAI) and foliage N-pool across populations of Artemisia ordosica In samples from northern China, a continuous increase of Narea with decreasing MI was achieved by a higher Nmass and constant SLA (reduced LAI and constant N-pool) in high-rainfall areas (MI > 0·29), but by a lower SLA and Nmass (reduced LAI and N-pool) in low-rainfall areas (MI ≤ 0·29). While δ(13)C, CCmass and CCarea continuously increased with decreasing MI, the low-rainfall group had higher Narea and δ(13)C at a given CCarea, compared with the high-rainfall group. Similar patterns were also found in additional data for the same species in the northern Tibetan Plateau. The observed drought threshold where MI = 0·29 corresponded well to the zonal boundary between typical and desert steppes in northern China. Our data indicated that below a climatic drought threshold, drought-resistant plants tend to maximize their intrinsic WUE through increased Narea at a given CCarea, which suggests a linkage between leaf functional traits and arid vegetation zonation. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please

  7. Is there a gap in the gap? Regional differences in the gender pay gap

    OpenAIRE

    Hirsch, Boris; König, Marion; Möller, Joachim

    2009-01-01

    In this paper, we investigate regional differences in the gender pay gap both theoretically and empirically. Within a spatial oligopsony model, we show that more densely populated labour markets are more competitive and constrain employers' ability to discriminate against women. Utilising a large administrative data set for western Germany and a flexible semi-parametric propensity score matching approach, we find that the unexplained gender pay gap for young workers is substantially lower in ...

  8. Linked data management

    CERN Document Server

    Hose, Katja; Schenkel, Ralf

    2014-01-01

    Linked Data Management presents techniques for querying and managing Linked Data that is available on today’s Web. The book shows how the abundance of Linked Data can serve as fertile ground for research and commercial applications. The text focuses on aspects of managing large-scale collections of Linked Data. It offers a detailed introduction to Linked Data and related standards, including the main principles distinguishing Linked Data from standard database technology. Chapters also describe how to generate links between datasets and explain the overall architecture of data integration systems based on Linked Data. A large part of the text is devoted to query processing in different setups. After presenting methods to publish relational data as Linked Data and efficient centralized processing, the book explores lookup-based, distributed, and parallel solutions. It then addresses advanced topics, such as reasoning, and discusses work related to read-write Linked Data for system interoperation. Desp...

  9. Explaining the Gender Wealth Gap

    Science.gov (United States)

    Ruel, Erin; Hauser, Robert M.

    2013-01-01

    To assess and explain the United States’ gender wealth gap, we use the Wisconsin Longitudinal Study to examine wealth accumulated by a single cohort over 50 years by gender, by marital status, and limited to the respondents who are their family’s best financial reporters. We find large gender wealth gaps between currently married men and women, and never-married men and women. The never-married accumulate less wealth than the currently married, and there is a marital disruption cost to wealth accumulation. The status-attainment model shows the most power in explaining gender wealth gaps between these groups explaining about one-third to one-half of the gap, followed by the human-capital explanation. In other words, a lifetime of lower earnings for women translates into greatly reduced wealth accumulation. A gender wealth gap remains between married men and women after controlling for the full model that we speculate may be related to gender differences in investment strategies and selection effects. PMID:23264038

  10. Virtual gap dielectric wall accelerator

    Science.gov (United States)

    Caporaso, George James; Chen, Yu-Jiuan; Nelson, Scott; Sullivan, Jim; Hawkins, Steven A

    2013-11-05

    A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

  11. Hard diffraction and rapidity gaps

    International Nuclear Information System (INIS)

    Brandt, A.

    1995-09-01

    The field of hard diffraction, which studies events with a rapidity gap and a hard scattering, has expanded dramatically recently. A review of new results from CDF, D OE, H1 and ZEUS will be given. These results include diffractive jet production, deep-inelastic scattering in large rapidity gap events, rapidity gaps between high transverse energy jets, and a search for diffractive W-boson production. The combination of these results gives new insight into the exchanged object, believed to be the pomeron. The results axe consistent with factorization and with a hard pomeron that contains both quarks and gluons. There is also evidence for the exchange of a strongly interacting color singlet in high momentum transfer (36 2 ) events

  12. ABORT GAP CLEANING IN RHIC

    International Nuclear Information System (INIS)

    DREES, A.; AHRENS, L.; III FLILLER, R.; GASSNER, D.; MCINTYRE, G.T.; MICHNOFF, R.; TRBOJEVIC, D.

    2002-01-01

    During the RHIC Au-run in 2001 the 200 MHz storage cavity system was used for the first time. The rebucketing procedure caused significant beam debunching in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam could account for approximately 30%-40% of the total beam intensity. Some of it will be in the abort gap. In order to minimize the risk of magnet quenching due to uncontrolled beam losses at the time of a beam dump, a combination of a fast transverse kicker and copper collimators were used to clean the abort gap. This report gives an overview of the gap cleaning procedure and the achieved performance

  13. Electrophysiological gap detection thresholds: effects of age and comparison with a behavioral measure.

    Science.gov (United States)

    Palmer, Shannon B; Musiek, Frank E

    2014-01-01

    Temporal processing ability has been linked to speech understanding ability and older adults often complain of difficulty understanding speech in difficult listening situations. Temporal processing can be evaluated using gap detection procedures. There is some research showing that gap detection can be evaluated using an electrophysiological procedure. However, there is currently no research establishing gap detection threshold using the N1-P2 response. The purposes of the current study were to 1) determine gap detection thresholds in younger and older normal-hearing adults using an electrophysiological measure, 2) compare the electrophysiological gap detection threshold and behavioral gap detection threshold within each group, and 3) investigate the effect of age on each gap detection measure. This study utilized an older adult group and younger adult group to compare performance on an electrophysiological and behavioral gap detection procedure. The subjects in this study were 11 younger, normal-hearing adults (mean = 22 yrs) and 11 older, normal-hearing adults (mean = 64.36 yrs). All subjects completed an adaptive behavioral gap detection procedure in order to determine their behavioral gap detection threshold (BGDT). Subjects also completed an electrophysiologic gap detection procedure to determine their electrophysiologic gap detection threshold (EGDT). Older adults demonstrated significantly larger gap detection thresholds than the younger adults. However, EGDT and BGDT were not significantly different in either group. The mean difference between EGDT and BGDT for all subjects was 0.43 msec. Older adults show poorer gap detection ability when compared to younger adults. However, this study shows that gap detection thresholds can be measured using evoked potential recordings and yield results similar to a behavioral measure. American Academy of Audiology.

  14. The Emissions Gap Report 2014

    DEFF Research Database (Denmark)

    Farrell, Timothy Clifford

    This fifth Emissions Gap report has a different focus from previous years. While it updates the 2020 emissions gap analysis, it gives particular attention to the implications of the global carbon dioxide emissions budget for staying within the 2 °C limit beyond 2020. It does so because countries...... are giving increasing attention to where they need to be in 2025, 2030 and beyond. Furthermore, this year’s update of the report benefits from the findings on the emissions budget from the latest series of Intergovernmental Panel on Climate Change (IPCC) reports...

  15. Gap filling strategies for long term energy flux data sets

    NARCIS (Netherlands)

    Falge, E.; Baldocchi, D.; Olson, R.; Anthoni, P.; Aubinet, M.; Bernhofer, C.; Burba, G.; Ceulemans, R.; Clement, R.; Dolman, H.; Granier, A.; Gross, P.; Grünwald, T.; Hollinger, D.; Jensen, N.O.; Katul, G.; Keronen, P.; Kowalski, A.; Lai, C.T.; Law, B.E.; Meyers, T.; Moncrieff, J.; Moors, E.J.; Munger, J.W.; Pilegaard, K.; Rebmann, C.; Suyker, A.; Tenhunen, J.; Tu, K.

    2001-01-01

    At present a network of over 100 field sites are measuring carbon dioxide, water vapor and sensible heat fluxes between the biosphere and atmosphere, on a nearly continuous basis. Gaps in the long term measurements of evaporation and sensible heat flux must be filled before these data can be used

  16. Assessment of interstate virtual water flows embedded in agriculture to mitigate water scarcity in India (1996-2014)

    Science.gov (United States)

    Katyaini, Suparana; Barua, Anamika

    2017-08-01

    India is the largest global freshwater user despite being highly water scarce. Agriculture is largest consumer of water and is most affected by water scarcity. Water scarcity is a persistent challenge in India, due to a gap in science and policy spheres. Virtual Water (VW) flows concept to mitigate water scarcity is at the science-policy interface. The paper aims to address the gap in VW research in India by first analyzing the interstate VW-flows embedded in food grains, and then linking these VW-flows with the water scarcity situation in the states, and elements of state and national water policies for the postreforms, and recovery periods of India's agriculture. There were net water savings (WS) of 207.5 PL during 1996-2014, indicating sustainable flows at the national level. WS increased from 11.2 TL/yr (1996-2005) to 25931.7 TL/yr (2005-2014), with the increase in interstate movement of food grains, and yield. However, unsustainable flows are seen at subnational scale, as VW-flows are from highly water-scarce states in North to highly water-scarce states in West and South. These flows are causing a concentration of water scarcity in water-scarce zones/states. Net VW imports were found to be driven by larger population and net VW exports by arable land. Further, the absence of state water policy cripples water management. Therefore, the paper argues that there is a need to rethink policy decisions on agriculture at the national and state level by internalizing water as a factor of production, through VW research.

  17. Drinking Water - National Drinking Water Clearinghouse

    Science.gov (United States)

    Savings Septic Unsafe Disposable Wipe Woes FacebookLogo FOCUS AREAS Drinking Water Wastewater Training Security Conservation & Water Efficiency Water We Drink Source Water Protection SORA/COI EPA MOU CartIcon Links Listserv Educators Homeowners Operators Small Systems Drinking Water Read On Tap Latest

  18. The Adaptation Gap Report - a Preliminary Assessment

    DEFF Research Database (Denmark)

    Alverson, Keith; Olhoff, Anne; Noble, Ian

    This first Adaptation Gap report provides an equally sobering assessment of the gap between adaptation needs and reality, based on preliminary thinking on how baselines, future goals or targets, and gaps between them might be defined for climate change adaptation. The report focuses on gaps...... in developing countries in three important areas: finance, technology and knowledge....

  19. Closing yield gaps: perils and possibilities for biodiversity conservation.

    Science.gov (United States)

    Phalan, Ben; Green, Rhys; Balmford, Andrew

    2014-04-05

    Increasing agricultural productivity to 'close yield gaps' creates both perils and possibilities for biodiversity conservation. Yield increases often have negative impacts on species within farmland, but at the same time could potentially make it more feasible to minimize further cropland expansion into natural habitats. We combine global data on yield gaps, projected future production of maize, rice and wheat, the distributions of birds and their estimated sensitivity to changes in crop yields to map where it might be most beneficial for bird conservation to close yield gaps as part of a land-sparing strategy, and where doing so might be most damaging. Closing yield gaps to attainable levels to meet projected demand in 2050 could potentially help spare an area equivalent to that of the Indian subcontinent. Increasing yields this much on existing farmland would inevitably reduce its biodiversity, and therefore we advocate efforts both to constrain further increases in global food demand, and to identify the least harmful ways of increasing yields. The land-sparing potential of closing yield gaps will not be realized without specific mechanisms to link yield increases to habitat protection (and restoration), and therefore we suggest that conservationists, farmers, crop scientists and policy-makers collaborate to explore promising mechanisms.

  20. The Widening Income Achievement Gap

    Science.gov (United States)

    Reardon, Sean F.

    2013-01-01

    Has the academic achievement gap between high-income and low-income students changed over the last few decades? If so, why? And what can schools do about it? Researcher Sean F. Reardon conducted a comprehensive analysis of research to answer these questions and came up with some striking findings. In this article, he shows that income-related…

  1. Closing the Gaps. Research Brief

    Science.gov (United States)

    Johnston, Howard

    2011-01-01

    Achievement gaps between groups of students (minority and white, rich and poor, English speakers and English language learners) are complex and intractable. Increasingly, they are being seen as a result of disparities between opportunities for learning available to different groups. By changing the opportunity structures of schools and…

  2. The Emissions Gap Report 2015

    DEFF Research Database (Denmark)

    Following the historic signing of the 2030 Agenda for Sustainable Development, this sixth edition of the UNEP Emissions Gap Report comes as world leaders start gathering in Paris to establish a new agreement on climate change. The report offers an independent assessment of the mitigation...

  3. Project LOCAL - Bridging The Gap

    Science.gov (United States)

    Haven, Robert N.

    1975-01-01

    Project LOCAL, a not-for-profit regional consortium, offers a broad spectrum of in-service training courses tailored to meet the needs of educators in various disciplines and levels of experience. The purpose of these offerings is to bridge the communication gap between innovative centers in computer-oriented education and staff members in Boston…

  4. Gender Wealth Gap in Slovakia

    NARCIS (Netherlands)

    S.K. Trommlerová (Sofia Karina)

    2017-01-01

    markdownabstractNo data on wealth has been available in Slovakia prior to Household Finance and Consumption Survey. Therefore, only studies on labor market participation and wage gender gaps are available to date. These studies indicate that Slovak women earn on average 25% less than men.

  5. Investigations of Pulsed Vacuum Gap.

    Science.gov (United States)

    1981-02-10

    Violet Spectra of Hot Sparks in Hh’Iacua, ’ ?hys. Rev., Vol. 12, p. 167, (1913). 31A Maitland , "Spark CondiiIoning Equation for Olane ElectrodesI-in...Appl. Phys., Vol. 1, 1291 G. Thecohilus, K. Srivastava, and R. ’ ian Heeswi.k, ’tn-situ Observation of !Microparticles in a Vacuum-Tnsulated Gap Using

  6. Featured Image: Simulating Planetary Gaps

    Science.gov (United States)

    Kohler, Susanna

    2017-03-01

    The authors model of howthe above disk would look as we observe it in a scattered-light image. The morphology of the gap can be used to estimate the mass of the planet that caused it. [Dong Fung 2017]The above image from a computer simulation reveals the dust structure of a protoplanetary disk (with the star obscured in the center) as a newly formed planet orbits within it. A recent study by Ruobing Dong (Steward Observatory, University of Arizona) and Jeffrey Fung (University of California, Berkeley) examines how we can determine mass of such a planet based on our observations of the gap that the planet opens in the disk as it orbits. The authors models help us to better understand how our observations of gaps might change if the disk is inclined relative to our line of sight, and how we can still constrain the mass of the gap-opening planet and the viscosity of the disk from the scattered-light images we have recently begun to obtain of distant protoplanetary disks. For more information, check out the paper below!CitationRuobing Dong () and Jeffrey Fung () 2017 ApJ 835 146. doi:10.3847/1538-4357/835/2/146

  7. Globalization and the Gender Gap

    NARCIS (Netherlands)

    Oostendorp, R.H.

    2004-01-01

    There are several theoretical reasons why globalization will have a narrowing as well as a widening effect on the gender wage gap, but little is known about the actual impact, except for some country studies. This study contributes to the literature in three respects. First, it is a large

  8. PSS: beyond the implementation gap

    NARCIS (Netherlands)

    Geertman, S.C.M.

    2017-01-01

    In the last couple of decades, a large number of papers on planning support systems (PSS) have been published in national and international, scientific and professional journals. What is remarkable about PSS is that for quite some time their history has been dominated by an implementation gap, that

  9. Denmark and the gap year

    DEFF Research Database (Denmark)

    Katznelson, Noemi; Juul, Tilde Mette

    2013-01-01

    This paper describes three different educational offers to young people: “The Folk High School”, “The ‘After-school’” and 10th class. All can be considered optional Gap Years. The following diagram shows how the Danish education system is structured. The Folk High School is a training course...

  10. On the growth of homogeneously nucleated water droplets in nitrogen: an experimental study

    Czech Academy of Sciences Publication Activity Database

    Fransen, M. A. L. J.; Sachteleben, E.; Hrubý, Jan; Smeulders, D. M. J.

    2014-01-01

    Roč. 55, č. 7 (2014), s. 1780-1780 ISSN 0723-4864 R&D Projects: GA ČR(CZ) GAP101/11/1593 Institutional support: RVO:61388998 Keywords : droplet nucleation * droplet growth * water Subject RIV: BJ - Thermodynamics Impact factor: 1.670, year: 2014 http://link.springer.com/article/10.1007%2Fs00348-014-1780-y

  11. Private Well Water and Fluoride

    Science.gov (United States)

    ... Private Wells Infant Formula Fluorosis Public Health Service Recommendation Water Operators & Engineers Water Fluoridation Additives Shortages of Fluoridation Additives Drinking Water Pipe Systems CDC-Sponsored Water Fluoridation Training Links to Other ...

  12. Optimizing a gap conductance model applicable to VVER-1000 thermal–hydraulic model

    International Nuclear Information System (INIS)

    Rahgoshay, M.; Hashemi-Tilehnoee, M.

    2012-01-01

    Highlights: ► Two known conductance models for application in VVER-1000 thermal–hydraulic code are examined. ► An optimized gap conductance model is developed which can predict the gap conductance in good agreement with FSAR data. ► The licensed thermal–hydraulic code is coupled with the gap conductance model predictor externally. -- Abstract: The modeling of gap conductance for application in VVER-1000 thermal–hydraulic codes is addressed. Two known models, namely CALZA-BINI and RELAP5 gap conductance models, are examined. By externally linking of gap conductance models and COBRA-EN thermal hydraulic code, the acceptable range of each model is specified. The result of each gap conductance model versus linear heat rate has been compared with FSAR data. A linear heat rate of about 9 kW/m is the boundary for optimization process. Since each gap conductance model has its advantages and limitation, the optimized gap conductance model can predict the gap conductance better than each of the two other models individually.

  13. Dynamic link: user's manual

    International Nuclear Information System (INIS)

    Harada, Hiroo; Asai, Kiyoshi; Kihara, Kazuhisa.

    1981-09-01

    The purpose of dynamic link facility is to link a load module dynamically only when it is used in execution time. The facility is very useful for development, execution and maintenance of a large scale computer program which is too big to be saved as one load module in main memory, or it is poor economy to save it due to many unused subroutines depending on an input. It is also useful for standardization and common utilization of programs. Standard usage of dynamic link facility of FACOM M-200 computer system, a software tool which analyzes the effect of dynamic link facility and application of dynamic link to nuclear codes are described. (author)

  14. Water footprint components required to address the water-energy-food nexus, with the recent Urban Water Atlas for Europe as an example

    Science.gov (United States)

    Vanham, Davy

    2017-04-01

    The first part of this presentation analyses which water footprint (WF) components are necessary in WF accounting to provide relevant information to address the Sustainable Development Goals (SDG's) water security (SDG 6), food security (SDG 2) and energy security (SDG 7) in a nexus setting. It is strongly based on the publication Vanham (2016) http://dx.doi.org/10.1016/j.ecoser.2015.08.003. First, the nexus links between (1) the planetary boundary freshwater resources (green and blue water resources) and (2) food, energy and blue water security are discussed. Second, it is shown which water uses are mostly represented in WF accounting. General water management and WF studies only account for the water uses agriculture, industry and domestic water. Important water uses are however mostly not identified as separate entities or even included, i.e. green and blue water resources for aquaculture, wild foods, biofuels, hydroelectric cooling, hydropower, recreation/tourism, forestry (for energy and other biomass uses) and navigation. Third, therefore a list of essential separate components to be included within WF accounting is presented. The latter would be more coherent with the water-food-energy-ecosystem nexus. The second part of the presentation gives a brief overview of the recently published Urban Water Atlas for Europe. It shows for a selected city which WF components are represented and which not. As such, it also identifies research gaps.

  15. Multi-flexural band gaps in an Euler–Bernoulli beam with lateral local resonators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ting, E-mail: WT323@mail.nwpu.edu.cn [School of Marine Science and Technology, Northwestern Polytechnical University, Xi' an, Shaanxi, 710072 (China); College of Engineering and Computer Science, The Australian National University, ACT, 2600 (Australia); Sheng, Mei-Ping [School of Marine Science and Technology, Northwestern Polytechnical University, Xi' an, Shaanxi, 710072 (China); Qin, Qing-Hua [College of Engineering and Computer Science, The Australian National University, ACT, 2600 (Australia)

    2016-02-05

    Flexural vibration suppression in an Euler–Bernoulli beam with attached lateral local resonators (LLR) is studied theoretically and numerically. Hamilton's principle and Bloch's theorem are employed to derive the dispersion relation which reveals that two band gaps are generated. Within both band gaps, the flexural waves are partially transformed into longitudinal waves through a four-link-mechanism and totally blocked. The band gaps can be flexibly tuned by changing the geometry parameter of the four-link-mechanism and the spring constants of the resonators. Frequency response function (FRF) from finite element analysis via commercial software of ANSYS shows large flexural wave attenuation within the band gaps and the effect of damping from the LLR substructures which helps smooth and lower the response peaks at the sacrifice of the band gap effect. The existence of the multi-flexural band gaps can be exploited for the design of flexural vibration control of beams. - Highlights: • A metamaterial beam with lateral local resonance is proposed. • The metamaterial beam can generate multi-band gaps for flexural wave suppression. • The substructure can transform the flexural wave into longitudinal wave and absorb the waves. • Damping from different part has different influence on the band gaps. • The design of the metamaterial beam can be used for multi-flexural vibration control.

  16. Emplacement Gantry Gap Analysis Study

    International Nuclear Information System (INIS)

    Thornley, R.

    2005-01-01

    To date, the project has established important to safety (ITS) performance requirements for structures, systems, and components (SSCs) based on the identification and categorization of event sequences that may result in a radiological release. These performance requirements are defined within the ''Nuclear Safety Design Bases for License Application'' (NSDB) (BSC 2005 [DIRS 171512], Table A-11). Further, SSCs credited with performing safety functions are classified as ITS. In turn, assurance that these SSCs will perform as required is sought through the use of consensus codes and standards. This gap analysis is based on the design completed for license application only. Accordingly, identification of ITS SSCs beyond those defined within the NSDB are based on designs that may be subject to further development during detail design. Furthermore, several design alternatives may still be under consideration to satisfy certain safety functions, and final selection will not be determined until further design development has occurred. Therefore, for completeness, alternative designs currently under consideration will be discussed throughout this study. This gap analysis will evaluate each code and standard identified within the ''Emplacement Gantry ITS Standards Identification Study'' (BSC 2005 [DIRS 173586]) to ensure each ITS performance requirement is fully satisfied. When a performance requirement is not fully satisfied, a gap is highlighted. This study will identify requirements to supplement or augment the code or standard to meet performance requirements. Further, this gap analysis will identify nonstandard areas of the design that will be subject to a design development plan. Nonstandard components and nonstandard design configurations are defined as areas of the design that do not follow standard industry practices or codes and standards. Whereby, assurance that an SSC will perform as required may not be readily sought though the use of consensus standards. This

  17. Gaps in EU Foreign Policy

    DEFF Research Database (Denmark)

    Larsen, Henrik

    of Capability-Expectations Gap in the study of European foreign policy. Through examples from relevant literature, Larsen not only demonstrates how this concept sets up standards for the EU as a foreign policy actor (that are not met by most other international actors) but also shows how this curtails analysis...... of EU foreign policy. The author goes on to discuss how the widespread use of the concept of ‘gap' affects the way in which EU foreign policy has been studied; and that it always produces the same result: the EU is an unfulfilled actor outside the realm of “normal” actors in IR. This volume offers new...... perspectives on European foreign policy research and advice and serves as an invaluable resource for students of EU foreign policy and, more broadly, European Studies....

  18. GAP Analysis. Bulletin Number 11

    Science.gov (United States)

    2002-01-01

    dynamics into ecotoxicology . Pages 281-317 in O.E. Rhodes, Jr., R.K. Chesser, and M.H. Smith, editors. Population dynamics in ecological space and time...current stewardship chapter of the GAP handbook states that ... human-induced barren, cultivated exotic-dominated, or ar- "...the process of categorizing...least some level of protection, very sible. The initial data used in developing the map was remotely little of our scrub/shrub, grassland, or cultivated

  19. Filling in biodiversity threat gaps

    DEFF Research Database (Denmark)

    Joppa, L. N.; O'Connor, Brian; Visconti, Piero

    2016-01-01

    increase to 10,000 times the background rate should species threatened with extinction succumb to pressures they face (4). Reversing these trends is a focus of the Convention on Biological Diversity's 2020 Strategic Plan for Biodiversity and its 20 Aichi Targets and is explicitly incorporated...... into the United Nations' 2030 Agenda for Sustainable Development and its 17 Sustainable Development Goals (SDGs). We identify major gaps in data available for assessing global biodiversity threats and suggest mechanisms for closing them....

  20. Hyper-active gap filling

    OpenAIRE

    Omaki, Akira; Lau, Ellen F.; Davidson White, Imogen; Dakan, Myles L.; Apple, Aaron; Phillips, Colin

    2015-01-01

    Much work has demonstrated that speakers of verb-final languages are able to construct rich syntactic representations in advance of verb information. This may reflect general architectural properties of the language processor, or it may only reflect a language-specific adaptation to the demands of verb-finality. The present study addresses this issue by examining whether speakers of a verb-medial language (English) wait to consult verb transitivity information before constructing filler-gap d...

  1. Hyper-active gap filling.

    Science.gov (United States)

    Omaki, Akira; Lau, Ellen F; Davidson White, Imogen; Dakan, Myles L; Apple, Aaron; Phillips, Colin

    2015-01-01

    Much work has demonstrated that speakers of verb-final languages are able to construct rich syntactic representations in advance of verb information. This may reflect general architectural properties of the language processor, or it may only reflect a language-specific adaptation to the demands of verb-finality. The present study addresses this issue by examining whether speakers of a verb-medial language (English) wait to consult verb transitivity information before constructing filler-gap dependencies, where internal arguments are fronted and hence precede the verb. This configuration makes it possible to investigate whether the parser actively makes representational commitments on the gap position before verb transitivity information becomes available. A key prediction of the view that rich pre-verbal structure building is a general architectural property is that speakers of verb-medial languages should predictively construct dependencies in advance of verb transitivity information, and therefore that disruption should be observed when the verb has intransitive subcategorization frames that are incompatible with the predicted structure. In three reading experiments (self-paced and eye-tracking) that manipulated verb transitivity, we found evidence for reading disruption when the verb was intransitive, although no such reading difficulty was observed when the critical verb was embedded inside a syntactic island structure, which blocks filler-gap dependency completion. These results are consistent with the hypothesis that in English, as in verb-final languages, information from preverbal noun phrases is sufficient to trigger active dependency completion without having access to verb transitivity information.

  2. Emerging semantics to link phenotype and environment

    Directory of Open Access Journals (Sweden)

    Anne E. Thessen

    2015-12-01

    Full Text Available Understanding the interplay between environmental conditions and phenotypes is a fundamental goal of biology. Unfortunately, data that include observations on phenotype and environment are highly heterogeneous and thus difficult to find and integrate. One approach that is likely to improve the status quo involves the use of ontologies to standardize and link data about phenotypes and environments. Specifying and linking data through ontologies will allow researchers to increase the scope and flexibility of large-scale analyses aided by modern computing methods. Investments in this area would advance diverse fields such as ecology, phylogenetics, and conservation biology. While several biological ontologies are well-developed, using them to link phenotypes and environments is rare because of gaps in ontological coverage and limits to interoperability among ontologies and disciplines. In this manuscript, we present (1 use cases from diverse disciplines to illustrate questions that could be answered more efficiently using a robust linkage between phenotypes and environments, (2 two proof-of-concept analyses that show the value of linking phenotypes to environments in fishes and amphibians, and (3 two proposed example data models for linking phenotypes and environments using the extensible observation ontology (OBOE and the Biological Collections Ontology (BCO; these provide a starting point for the development of a data model linking phenotypes and environments.

  3. Assessing Antiretroviral Use During Gaps in HIV Primary Care Using Multisite Medicaid Claims and Clinical Data.

    Science.gov (United States)

    Monroe, Anne K; Fleishman, John A; Voss, Cindy C; Keruly, Jeanne C; Nijhawan, Ank E; Agwu, Allison L; Aberg, Judith A; Rutstein, Richard M; Moore, Richard D; Gebo, Kelly A

    2017-09-01

    Some individuals who appear poorly retained by clinic visit-based retention measures are using antiretroviral therapy (ART) and maintaining viral suppression. We examined whether individuals with a gap in HIV primary care (≥180 days between HIV outpatient clinic visits) obtained ART during that gap after 180 days. HIV Research Network data from 5 sites and Medicaid Analytic Extract eligibility and pharmacy data were combined. Factors associated with having both an HIV primary care gap and a new (ie, nonrefill) ART prescription during a gap were evaluated with multinomial logistic regression. Of 6892 HIV Research Network patients, 6196 (90%) were linked to Medicaid data, and 4275 had any Medicaid ART prescription. Over half (54%) had occasional gaps in HIV primary care. Women, older people, and those with suppressed viral load were less likely to have a gap. Among those with occasional gaps (n = 2282), 51% received a new ART prescription in a gap. Viral load suppression before gap was associated with receiving a new ART prescription in a gap (odds ratio = 1.91, 95% confidence interval: 1.57 to 2.32), as was number of days in a gap (odds ratio = 1.04, 95% confidence interval: 1.02 to 1.05), and the proportion of months in the gap enrolled in Medicaid. Medicaid-insured individuals commonly receive ART during gaps in HIV primary care, but almost half do not. Retention measures based on visit frequency data that do not incorporate receipt of ART and/or viral suppression may misclassify individuals who remain suppressed on ART as not retained.

  4. [Research progress of larger flexion gap than extension gap in total knee arthroplasty].

    Science.gov (United States)

    Zhang, Weisong; Hao, Dingjun

    2017-05-01

    To summarize the progress of larger flexion gap than extension gap in total knee arthro-plasty (TKA). The domestic and foreign related literature about larger flexion gap than extension gap in TKA, and its impact factors, biomechanical and kinematic features, and clinical results were summarized. During TKA, to adjust the relations of flexion gap and extension gap is one of the key factors of successful operation. The biomechanical, kinematic, and clinical researches show that properly larger flexion gap than extension gap can improve both the postoperative knee range of motion and the satisfaction of patients, but does not affect the stability of the knee joint. However, there are also contrary findings. So adjustment of flexion gap and extension gap during TKA is still in dispute. Larger flexion gap than extension gap in TKA is a new joint space theory, and long-term clinical efficacy, operation skills, and related complications still need further study.

  5. The Gamma Gap and All-Cause Mortality.

    Directory of Open Access Journals (Sweden)

    Stephen P Juraschek

    Full Text Available The difference between total serum protein and albumin, i.e. the gamma gap, is a frequently used clinical screening measure for both latent infection and malignancy. However, there are no studies defining a positive gamma gap. Further, whether it is an independent risk factor of mortality is unknown.This study examined the association between gamma gap, all-cause mortality, and specific causes of death (cardiovascular, cancer, pulmonary, or other in 12,260 participants of the National Health and Nutrition Examination Survey (NHANES from 1999-2004. Participants had a comprehensive metabolic panel measured, which was linked with vital status data from the National Death Index. Cause of death was based on ICD10 codes from death certificates. Analyses were performed with Cox proportional hazards models adjusted for mortality risk factors. The mean (SE age was 46 (0.3 years and the mean gamma gap was 3.0 (0.01 g/dl. The population was 52% women and 10% black. During a median follow-up period of 4.8 years (IQR: 3.3 to 6.2 years, there were 723 deaths. The unadjusted 5-year cumulative incidences across quartiles of the gamma gap (1.7-2.7, 2.8-3.0, 3.1-3.2, and 3.3-7.9 g/dl were 5.7%, 4.2%, 5.5%, and 7.8%. After adjustment for risk factors, participants with a gamma gap of ≥3.1 g/dl had a 30% higher risk of death compared to participants with a gamma gap <3.1 g/dl (HR: 1.30; 95%CI: 1.08, 1.55; P = 0.006. Gamma gap (per 1.0 g/dl was most strongly associated with death from pulmonary causes (HR 2.22; 95%CI: 1.19, 4.17; P = 0.01.The gamma gap is an independent risk factor for all-cause mortality at values as low as 3.1 g/dl (in contrast to the traditional definition of 4.0 g/dl, and is strongly associated with death from pulmonary causes. Future studies should examine the biologic pathways underlying these associations.

  6. The Gamma Gap and All-Cause Mortality

    Science.gov (United States)

    Juraschek, Stephen P.; Moliterno, Alison R.; Checkley, William; Miller, Edgar R.

    2015-01-01

    Background The difference between total serum protein and albumin, i.e. the gamma gap, is a frequently used clinical screening measure for both latent infection and malignancy. However, there are no studies defining a positive gamma gap. Further, whether it is an independent risk factor of mortality is unknown. Methods and Findings This study examined the association between gamma gap, all-cause mortality, and specific causes of death (cardiovascular, cancer, pulmonary, or other) in 12,260 participants of the National Health and Nutrition Examination Survey (NHANES) from 1999–2004. Participants had a comprehensive metabolic panel measured, which was linked with vital status data from the National Death Index. Cause of death was based on ICD10 codes from death certificates. Analyses were performed with Cox proportional hazards models adjusted for mortality risk factors. The mean (SE) age was 46 (0.3) years and the mean gamma gap was 3.0 (0.01) g/dl. The population was 52% women and 10% black. During a median follow-up period of 4.8 years (IQR: 3.3 to 6.2 years), there were 723 deaths. The unadjusted 5-year cumulative incidences across quartiles of the gamma gap (1.7–2.7, 2.8–3.0, 3.1–3.2, and 3.3–7.9 g/dl) were 5.7%, 4.2%, 5.5%, and 7.8%. After adjustment for risk factors, participants with a gamma gap of ≥3.1 g/dl had a 30% higher risk of death compared to participants with a gamma gap gap (per 1.0 g/dl) was most strongly associated with death from pulmonary causes (HR 2.22; 95%CI: 1.19, 4.17; P = 0.01). Conclusions The gamma gap is an independent risk factor for all-cause mortality at values as low as 3.1 g/dl (in contrast to the traditional definition of 4.0 g/dl), and is strongly associated with death from pulmonary causes. Future studies should examine the biologic pathways underlying these associations. PMID:26629820

  7. Gap filling strategies for long term energy flux data sets

    DEFF Research Database (Denmark)

    Falge, E.; Baldocchi, D.; Olson, R.

    2001-01-01

    At present a network of over 100 field sites are measuring carbon dioxide, water vapor and sensible heat fluxes between the biosphere and atmosphere, on a nearly continuous basis. Gaps in the long term measurements of evaporation and sensible heat flux must be filled before these data can be used...... for hydrological and meteorological applications. We adapted methods of gap filling for NEE (net ecosystem exchange of carbon) to energy fluxes and applied them to data sets available from the EUROFLUX and AmeriFlux eddy covariance databases. The average data coverage for the sites selected was 69% and 75......% for latent heat (lambdaE) and sensible heat (H). The methods were based on mean diurnal variations (half-hourly binned means of fluxes based on previous and subsequent days, MDV) and look-up tables for fluxes during assorted meteorological conditions (LookUp), and the impact of different gap filling methods...

  8. Visualisierung von typisierten Links in Linked Data

    Directory of Open Access Journals (Sweden)

    Georg Neubauer

    2017-09-01

    Full Text Available Das Themengebiet der Arbeit behandelt Visualisierungen von typisierten Links in Linked Data. Die wissenschaftlichen Gebiete, die im Allgemeinen den Inhalt des Beitrags abgrenzen, sind das Semantic Web, das Web of Data und Informationsvisualisierung. Das Semantic Web, das von Tim Berners Lee 2001 erfunden wurde, stellt eine Erweiterung zum World Wide Web (Web 2.0 dar. Aktuelle Forschungen beziehen sich auf die Verknüpfbarkeit von Informationen im World Wide Web. Um es zu ermöglichen, solche Verbindungen wahrnehmen und verarbeiten zu können sind Visualisierungen die wichtigsten Anforderungen als Hauptteil der Datenverarbeitung. Im Zusammenhang mit dem Sematic Web werden Repräsentationen von zuhammenhängenden Informationen anhand von Graphen gehandhabt. Der Grund des Entstehens dieser Arbeit ist in erster Linie die Beschreibung der Gestaltung von Linked Data-Visualisierungskonzepten, deren Prinzipien im Rahmen einer theoretischen Annäherung eingeführt werden. Anhand des Kontexts führt eine schrittweise Erweiterung der Informationen mit dem Ziel, praktische Richtlinien anzubieten, zur Vernetzung dieser ausgearbeiteten Gestaltungsrichtlinien. Indem die Entwürfe zweier alternativer Visualisierungen einer standardisierten Webapplikation beschrieben werden, die Linked Data als Netzwerk visualisiert, konnte ein Test durchgeführt werden, der deren Kompatibilität zum Inhalt hatte. Der praktische Teil behandelt daher die Designphase, die Resultate, und zukünftige Anforderungen des Projektes, die durch die Testung ausgearbeitet wurden.

  9. Narrowing Maize Yield Gaps Under Rain-fed conditions in Tanzania ...

    African Journals Online (AJOL)

    Abstract. The wide gap between potential and actual yields of maize in Tanzania, due low productivity is the major constraint to ... An International Journal of Basic and Applied Research ... for determining maize grain yield followed by water.

  10. The Øresund Link

    DEFF Research Database (Denmark)

    Møller, Jacob Steen

    "Øresundsbron" is the combined bridge and tunnel connecting Denmark and Sweden adjacent to Copenhagen. Øresundsbron was built and is operated by a consortium owned jointly by the Danish and Swedish states. The Link was inaugurated 1 July 2000 by the Queen of Denmark and the King of Sweden. The 16......-km link across the Sound could potentially impact the water exchange between the Baltic Sea and the North Sea, and the dredging activities during construction were a threat to the local marine environment. The public interest in the environmental issues together with a pro-active environmental policy...... of hydrodynamic modelling, on line monitoring and access to all environmental information through a GIS based information system. The public attitude towards the project in general and the environmental impact in particular shifted from a very sceptical one at the beginning of the project to a very positive one...

  11. Colorado Water Institute

    Science.gov (United States)

    Colorado Water Institute Colorado State University header HomeMission StatementGRAD592NewslettersPublications/ReportsCSU Water ExpertsFunding OpportunitiesScholarshipsSubscribeEmploymentAdvisory BoardStaffContact UsCommentsLinks Water Center Logo Water Resources Archive Office of Engagement Ag Water

  12. Biological Water Quality Criteria

    Science.gov (United States)

    Page contains links to Technical Documents pertaining to Biological Water Quality Criteria, including, technical assistance documents for states, tribes and territories, program overviews, and case studies.

  13. Linking open vocabularies

    CERN Document Server

    Greifender, Elke; Seadle, Michael

    2013-01-01

    Linked Data (LD), Linked Open Data (LOD) and generating a web of data, present the new knowledge sharing frontier. In a philosophical context, LD is an evolving environment that reflects humankinds' desire to understand the world by drawing on the latest technologies and capabilities of the time. LD, while seemingly a new phenomenon did not emerge overnight; rather it represents the natural progression by which knowledge structures are developed, used, and shared. Linked Open Vocabularies is a significant trajectory of LD. Linked Open Vocabularies targets vocabularies that have traditionally b

  14. Yield gap analysis of Chickpea under semi-arid conditions: A simulation study

    OpenAIRE

    seyed Reza Amiri Deh ahmadi; mehdi parsa; mohammad bannayan aval; mahdi nassiri mahallati

    2016-01-01

    Yield gap analysis provides an essential framework to prioritize research and policy efforts aimed at reducing yield constraints. To identify options for increasing chickpea yield, the SSM-chickpea model was parameterized and evaluated to analyze yield potentials, water limited yields and yield gaps for nine regions representing major chickpea-growing areas of Razavi Khorasan province. The average potential yield of chickpea for the locations was 2251 kg ha-1, while the water limited yield wa...

  15. Experimental study of a spark-gap

    International Nuclear Information System (INIS)

    Bruzzone, H.; Moreno, C.; Vieytes, R.

    1990-01-01

    Some experimental results concerning to the resistance of an atmospheric pressure spark-gap, operating in the self breakdown regime are presented. The influence of the energy discharging through the gap on this resistance is discussed. (Author)

  16. Bridging the Gap Between Theory and Practice

    OpenAIRE

    Roy H.M. Sembel

    2015-01-01

    Some concerns in the field of Business Management regarding the gap between theory and practice have been raised by practitioners and academicians. This keynote speech describes some lessons learned from the academic literature regarding this gap (whether the gap really exists, and if it exists, whether it needs to be bridged or closed, and how to bridge or close this gap), and shares the author's personal and professional experiences of living as both an academician and a practitioner. The m...

  17. Gap Year: Time off, with a Plan

    Science.gov (United States)

    Torpey, Elka Maria

    2009-01-01

    A gap year allows people to step off the usual educational or career path and reassess their future. According to people who have taken a gap year, the time away can be well worth it. This article can help a person decide whether to take a gap year and how to make the most of his time off. It describes what a gap year is, including its pros and…

  18. "Explaining the Gender Wage Gap in Georgia"

    OpenAIRE

    Tamar Khitarishvili

    2009-01-01

    This paper evaluates gender wage differentials in Georgia between 2000 and 2004. Using ordinary least squares, we find that the gender wage gap in Georgia is substantially higher than in other transition countries. Correcting for sample selection bias using the Heckman approach further increases the gender wage gap. The Blinder Oaxaca decomposition results suggest that most of the wage gap remains unexplained. The explained portion of the gap is almost entirely attributed to industrial variab...

  19. Gap Analysis: Rethinking the Conceptual Foundations

    Science.gov (United States)

    2008-04-23

    there could exist a basis for gap in capability and, therefore, a desire to close the capability gap . What one desires versus what one has is, in...Analysis is not intended to close the space between the most distant extremes or the rarest occurrences. Rather, Gap Analysis is centered on the larger...åÖÉ=======- 13 - = = Research Objectives The process of identifying needs and unsatisfied desires, or gaps in capability—in essence, the goal—is

  20. Hyper-active gap filling

    Directory of Open Access Journals (Sweden)

    Akira eOmaki

    2015-04-01

    Full Text Available Much work has demonstrated that speakers of verb-final languages are able to construct rich syntactic representations in advance of verb information. This may reflect general architectural properties of the language processor, or it may only reflect a language-specific adaptation to the demands of verb-finality. The present study addresses this issue by examining whether speakers of a verb-medial language (English wait to consult verb transitivity information before constructing filler-gap dependencies, where internal arguments are fronted and hence precede the verb. This configuration makes it possible to investigate whether the parser actively makes representational commitments on the gap position before verb transitivity information becomes available. A key prediction of the view that rich pre-verbal structure-building is a general architectural property is that speakers of verb-medial languages should predictively construct dependencies in advance of verb transitivity information, and therefore that disruption should be observed when the verb has intransitive subcategorization frames that are incompatible with the predicted structure. In three reading experiments (self-paced and eye-tracking that manipulated verb transitivity, we found evidence for reading disruption when the verb was intransitive, although no such reading difficulty was observed when the critical verb was embedded inside a syntactic island structure, which blocks filler-gap dependency completion. These results are consistent with the hypothesis that in English, as in verb-final languages, information from preverbal NPs is sufficient to trigger active dependency completion without having access to verb transitivity information.