21 research outputs found

    Point rainfall statistics for ecohydrological analyses derived from satellite integrated rainfall measurements

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    ABSTRACT: Satellite rainfall measurements, nowadays commonly available, provide valuable information about the spatial structure of rainfall. In areas with low-density rain gage networks, or where these networks are nonexistent, satellite rainfall measurements can also provide useful estimates to be used as virtual rain gages. However, satellite and rain gage measurements are statistically different in nature and cannot be directly compared to one another. In the present paper, we develop a methodology to downscale satellite rainfall measurements to generate rain-gage-equivalent statistics. We apply the methodology to four locations along a strong rainfall gradient in the Kalahari transect, southern Africa, to validate the methodology. We show that the method allows the estimation of point rainfall statistics where only satellite measurements exist. Point rainfall statistics are key descriptors for ecohydrologic studies linking the response of vegetation to rainfall dynamics

    On the sensitivity of tidal network characterization to power law estimation

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    ABSTRACT. Long-term simulations (3000 yr) of an idealized basin using different tidal ranges (1, 2 and 3 m) and grain sizes (120, 480 and 960 μm) have been performed in order to cover a range of hydrodynamic and sedimentary conditions. Two different cell sizes (50 and 100 m) have been used to study the impact of cell size on tidal network development. The probability distributions of the drainage area and the drainage volume have been computed for every simulation (during an ebb and a flood phase). Power law distributions are observed in drainage area and drainage volume distribution. As an objective estimation of the exponent of a power law is an open issue, different approaches (linear binning, normalized logarithmic binning, cumulative distribution function and maximum likelihood) proposed by White et al. (2008) to estimate the exponent have been used to carry out a sensitivity analysis. Our findings indicate that although all methods results in high and significant correlation coefficients, more work is needed to develop a universal, objective estimation of the exponent

    Interbasin Water Transfer, Riverine Connectivity, and Spatial Controls on Fish Biodiversity

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    BACKGROUND: Large-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fish communities. Because connectivity in habitat networks is expected to be critical to species' biogeography, consideration of changes in the relative isolation of riverine networks may provide a strategy for controlling impacts of IBWTs on freshwater fish communities. METHODS/PRINCIPAL FINDINGS: Using empirical data on the current patterns of freshwater fish biodiversity for rivers of peninsular India, we show here how the spatial changes alone under an archetypal IBWT project will (1) reduce freshwater fish biodiversity system-wide, (2) alter patterns of local species richness, (3) expand distributions of widespread species throughout peninsular rivers, and (4) decrease community richness by increasing inter-basin similarity (a mechanism for the observed decrease in biodiversity). Given the complexity of the IBWT, many paths to partial or full completion of the project are possible. We evaluate two strategies for step-wise implementation of the 11 canals, based on economic or ecological considerations. We find that for each step in the project, the impacts on freshwater fish communities are sensitive to which canal is added to the network. CONCLUSIONS/SIGNIFICANCE: Importantly, ecological impacts can be reduced by associating the sequence in which canals are added to characteristics of the links, except for the case when all 11 canals are implemented simultaneously (at which point the sequence of canal addition is inconsequential). By identifying the fundamental relationship between the geometry of riverine networks and freshwater fish biodiversity, our results will aid in assessing impacts of IBWT projects and balancing ecosystem and societal demands for freshwater, even in cases where biodiversity data are limited

    Scaling properties of tidal networks

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    A new methodology is developed to extract tidal network from hydrodynamic conditions, and use data derived from numerical modeling or field observations to test the hypothesis that tidal networks are characterized by scale-invariant properties. Different tidal network configurations have been obtained from long-term numerical simulations in an idealized basin. These simulations show the influence of hydrodynamic conditions (tidal range, TR) and sediment (grain size sediment, D50) on the final configuration of the network. One of the signatures of scale-invariant behavior is related to the presence of a power law relationship in the probability distribution of geometrical characteristics. For each model configuration and field site, the probability distribution of drainage area and the drainage volume has been calculated, and in both cases tidal networks show scale-invariant characteristics. After assessing the sensitivity of the results, an energy expenditure analysis shows that tidal basins evolve toward a state with less morphodynamic activity, with a lower energy expenditure compare with the initial state

    Effectiveness of a strategy that uses educational games to implement clinical practice guidelines among Spanish residents of family and community medicine (e-EDUCAGUIA project):A clinical trial by clusters

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    This study was funded by the Fondo de Investigaciones Sanitarias FIS Grant Number PI11/0477 ISCIII.-REDISSEC Proyecto RD12/0001/0012 AND FEDER Funding.Background: Clinical practice guidelines (CPGs) have been developed with the aim of helping health professionals, patients, and caregivers make decisions about their health care, using the best available evidence. In many cases, incorporation of these recommendations into clinical practice also implies a need for changes in routine clinical practice. Using educational games as a strategy for implementing recommendations among health professionals has been demonstrated to be effective in some studies; however, evidence is still scarce. The primary objective of this study is to assess the effectiveness of a teaching strategy for the implementation of CPGs using educational games (e-learning EDUCAGUIA) to improve knowledge and skills related to clinical decision-making by residents in family medicine. The primary objective will be evaluated at 1 and 6months after the intervention. The secondary objectives are to identify barriers and facilitators for the use of guidelines by residents of family medicine and to describe the educational strategies used by Spanish teaching units of family and community medicine to encourage implementation of CPGs. Methods/design: We propose a multicenter clinical trial with randomized allocation by clusters of family and community medicine teaching units in Spain. The sample size will be 394 residents (197 in each group), with the teaching units as the randomization unit and the residents comprising the analysis unit. For the intervention, both groups will receive an initial 1-h session on clinical practice guideline use and the usual dissemination strategy by e-mail. The intervention group (e-learning EDUCAGUIA) strategy will consist of educational games with hypothetical clinical scenarios in a virtual environment. The primary outcome will be the score obtained by the residents on evaluation questionnaires for each clinical practice guideline. Other included variables will be the sociodemographic and training variables of the residents and the teaching unit characteristics. The statistical analysis will consist of a descriptive analysis of variables and a baseline comparison of both groups. For the primary outcome analysis, an average score comparison of hypothetical scenario questionnaires between the EDUCAGUIA intervention group and the control group will be performed at 1 and 6months post-intervention, using 95% confidence intervals. A linear multilevel regression will be used to adjust the model. Discussion: The identification of effective teaching strategies will facilitate the incorporation of available knowledge into clinical practice that could eventually improve patient outcomes. The inclusion of information technologies as teaching tools permits greater learning autonomy and allows deeper instructor participation in the monitoring and supervision of residents. The long-term impact of this strategy is unknown; however, because it is aimed at professionals undergoing training and it addresses prevalent health problems, a small effect can be of great relevance. Trial registration: ClinicalTrials.gov: NCT02210442.Publisher PDFPeer reviewe

    Innovación del Diseño para el Desarrollo Social

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    Una labor de síntesis alrededor de la gran temática de este libro que surge a partir de una serie de reflexiones y propuestas encaminadas desde la innovación del diseño para el desarrollo social, refleja una invitación al lector para enunciar a partir de su lectura nuevas discusiones sobre el quehacer del diseño con una perspectiva de innovación para este tipo de desarrollo, es pues este texto una invitación a enunciar nuevos retos y diálogos partiendo de reconocer al desarrollo social como uno de los pilares fundamentales desde la Organización de las Naciones Unidas (ONU) como parte fundamental para garantizar el mejoramiento de la vida de las personas. Desde la disciplina del diseño y retomado como eje para su discusión se pretendería establecer una serie de reflexiones y acciones que permitan atender situaciones para grupos minoritarios y vulnerables, así como apoyar esfuerzos encaminados a mejorar la calidad de vida de los integrantes de grupos y sociedades establecidas y recuperar el patrimonio cultural como parte fundamental de las identidades culturales y por tanto de la historia de la humanidad.A lo largo de la historia, el diseño, en cualquiera de sus manifestaciones, ha estado presente en todos los ámbitos. Se ha convertido en una disciplina que evoluciona al ritmo de las sociedades, que se pone al servicio de las necesidades de mercado pero también de las que requieren un abordaje distinto, observadas desde una mirada que concierne a lo social, entendido éste como lo que se reproduce o se instaura en el colectivo, en el grupo, en las comunidades, en las sociedades como parte significativa de sus cotidianeidades. El Diseño desde esta perspectiva acompaña al ser humano produciendo una significación de los objetos como parte fundamental de sus vidas, que transforma una realidad deseada en una realidad concreta, de aquí la importancia de crear una conciencia social para la praxis laboral de esta disciplina. En este sentido el campo profesional, académico y de investigación del diseño debe ocuparse de crear, difundir y divulgar el quehacer de la misma, manifestando un equilibrio entre conciencia, racionalidad y la realidad. Desde el contexto planteado, la Universidad Autónoma del Estado de México, a través de su Facultad de Arquitectura y Diseño presenta en esta obra una serie de reflexiones en torno al papel que desempeña el diseño humanístico, científico y tecnológico desde un enfoque de vanguardia e innovación para el desarrollo social, como resultado de la experiencia vertida en el Coloquio Internacional de Diseño que organiza éste año este espacio académico, en donde cada una de las aportaciones refleja la experiencia de cada uno de sus participantes; con base en ello, el presente libro integrado por una compilación de trabajos ofrece descripciones, análisis y propuestas que contribuyen a la solución de problemas procurando un desarrollo social

    Random functions and hydrology

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    New Frontiers of Hydrology

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    Papers submitted for this special section are selected contributions presented during ‘‘New Frontiers of Hydrology’’ Workshops held in Princeton (USA) in 2003 and in Capri (Italy) in 200

    Scaling laws for river networks

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