51 research outputs found

    Classification and area estimation of land covers in Kansas using ground-gathered and LANDSAT digital data

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    Ground-gathered data and LANDSAT multispectral scanner (MSS) digital data from 1981 were analyzed to produce a classification of Kansas land areas into specific types called land covers. The land covers included rangeland, forest, residential, commercial/industrial, and various types of water. The analysis produced two outputs: acreage estimates with measures of precision, and map-type or photo products of the classification which can be overlaid on maps at specific scales. State-level acreage estimates were obtained and substate-level land cover classification overlays and estimates were generated for selected geographical areas. These products were found to be of potential use in managing land and water resources

    Comparison of two methods to assess heterogeneity of water flow in soils

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    The heterogeneity of water flow and solute transport was assessed during radioactive tracer infiltration experiment in a black clay loam soil using modified methods to estimate the effective cross section (ECS) and the degree of preferential flow (DPF). The results of field and numerical experiments showed that these parameters characterized the heterogeneity of water flow in the soils unequivocally. The ECS decreases non-linearly and the DPF increases linearly with an increase of the bypassing ratio (ratio of macropore flow rate to total flow rate). The ECS decreased and the DPF increased with depth, which suggests an increase in the heterogeneity of water flow with depth. The plot of the DPF against ECS values calculated from the tracer experiment data was consistent with the relationship obtained by the numerical simulation assuming preferential flow in the neighbourhood of three probes

    Annotating the human genome with Disease Ontology

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    <p>Abstract</p> <p>Background</p> <p>The human genome has been extensively annotated with Gene Ontology for biological functions, but minimally computationally annotated for diseases.</p> <p>Results</p> <p>We used the Unified Medical Language System (UMLS) MetaMap Transfer tool (MMTx) to discover gene-disease relationships from the GeneRIF database. We utilized a comprehensive subset of UMLS, which is disease-focused and structured as a directed acyclic graph (the Disease Ontology), to filter and interpret results from MMTx. The results were validated against the Homayouni gene collection using recall and precision measurements. We compared our results with the widely used Online Mendelian Inheritance in Man (OMIM) annotations.</p> <p>Conclusion</p> <p>The validation data set suggests a 91% recall rate and 97% precision rate of disease annotation using GeneRIF, in contrast with a 22% recall and 98% precision using OMIM. Our thesaurus-based approach allows for comparisons to be made between disease containing databases and allows for increased accuracy in disease identification through synonym matching. The much higher recall rate of our approach demonstrates that annotating human genome with Disease Ontology and GeneRIF for diseases dramatically increases the coverage of the disease annotation of human genome.</p

    Turismo acessível para todos, um paradigma emergente e um desafio para a oferta turística. O caso dos espaços museológicos e empreendimentos turísticos de Cascais.

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    Reflexão sobre o turismo acessível para todos, como modelo que se revela cada vez mais essencial para todo o sistema turístico, que se afirma não só pela sua relevância social, cívica e demográfica mas também pelas potencialidades económicas associadas. Todavia, o turismo acessível constitui um desafio de adaptação para a oferta turística instalada há vários anos, em destinos turísticos mais antigos, como é o caso de Cascais.Reflection on accessible tourism for all, as an increasingly essential model for the touristic system, that claims not only for its social, civic and demographic significance, but also for the economic potential associated. However, the accessible tourism is an adaptation challenge for the elderly tourism supply, at long-established tourism destinations, such as Cascais

    Land use change impacts on floods at the catchment scale: Challenges and opportunities for future research

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    Research gaps in understanding flood changes at the catchment scale caused by changes in forest management, agricultural practices, artificial drainage and terracing are identified. Potential strategies in addressing these gaps are proposed, such as complex systems approaches to link processes across time scales, long-term experiments on physical-chemical-biological process interactions, and a focus on connectivity and patterns across spatial scales. It is suggested that these strategies will stimulate new research that coherently addresses the issues across hydrology, soil and agricultural sciences, forest engineering, forest ecology and geomorphology

    Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

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    Lawson criterion for ignition exceeded in an inertial fusion experiment

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    For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

    Twenty-three unsolved problems in hydrology (UPH) – a community perspective

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    This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through on-line media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focussed on process-based understanding of hydrological variability and causality at all space and time scales. Increased attention to environmental change drives a new emphasis on understanding how change propagates across interfaces within the hydrological system and across disciplinary boundaries. In particular, the expansion of the human footprint raises a new set of questions related to human interactions with nature and water cycle feedbacks in the context of complex water management problems. We hope that this reflection and synthesis of the 23 unsolved problems in hydrology will help guide research efforts for some years to come

    Isotopic hydrograph separation in two small mountain catchments during multiple events

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    Two-component isotopic hydrograph separation (IHS) was developed to determine the event- and pre-event components of a single storm event. Its application for several sucessive events requires repeated determination of isotopic signatures of end-members (precipitation, pre-event component) for each event. The existence of several possible alternative signatures results in differences in calculated contributions of event-/pre- event components. This article addresses the question of how big the differences could be in small mountain catchments with different methods for detemining the end member signatures. We analyzed data on isotopic composition of daily/event precipitation at different elevations in two catchments located in the highest part of the Carpathians in July 2014.The isotopic composition of streamflow sampled every 4-6 hours was analyzed as well. Elevational gradients of δ18O and δ2H in precipitation in the study period were -0.18 ‰ 100 m-1 and -1.1 ‰ 100 m-1, respectively. An elevation gradient in deuterium excess (0.29 ‰ 100 m-1) was also found. Precipitation on the windward side of the mountains was isotopically lighter than expected for a given rain gauge elevation. Five large rainfall-runoff events occurred in the study period in the meso-scale catchment of the Jalovecký creek (Western Tatra Mountains, area 22.2 km2) and in the headwater catchment of the Škaredý creek (High Tatra Mountains, area 1.4 km2). Isotopic hydrograph separation was conducted using eight options for the isotopic signatures of event and pre-event water. The isotopic signature of the event water (rainfall) was alternatively represented by data from high or low elevations. Pre-event water was represented either by the streamflow before the event or by the value taken from the statistics of the long-term data on isotopic composition of the stream. Both isotopes (18O and 2H) were used to calculate event water fractions during peak flows of individual events. Calculated peak flow event water fractions were below 0.2-0.3 for most events. However, the differences in calculated event water fractions for alternative isotopic composition of end-members were significant even if we did not take into account changes in isotopic composition during individual rainfalls. Coefficients of variation for event water fractions calculated for various options varied during individual events from 0.14 to 0.36. It is therefore perhaps better to use a range of possible values instead of a single accurate number to interpret the IHS results. Hydrograph separations based on 18O and 2H provided similar results.Se llevó a cabo una separación isotópica del hidrograma en dos componentes con el fin de determinar la proporción de agua de lluvia y de agua preexistente de un único evento de crecida. Su aplicación para varios eventos sucesivos requiere la determinación reiterada de las señales isotópicas de los distintos componentes (precipitación, agua preexistente) para cada evento. La existencia de varias señales posibles conlleva diferencias en el cálculo de las contribuciones de los distintos componentes. Este artículo responde a la pregunta de cuánto de grandes podrían ser las diferencias debidas a la aplicación de diferentes métodos para la determinación de las señales de los distintos componentes en una pequeña cuenca de montaña. Se analizó la composición isotópica de la lluvia diaria y a escala de evento, a diferentes altitudes en dos cuencas localizadas en los Cárpatos en julio de 2014. La composición isotópica del caudal, muestreado cada 4-6 h, también se analizó. Los gradientes altitudinales de δ18O y δ2H en la precipitación durante el periodo de estudio fueron 0.18 ‰ 100 m-1 y -1.1 ‰ 100 m-1. También se observó un gradiente altitudinal en el exceso de deuterio (0.29 ‰ 100 m-1). La precipitación en la cara norte de las montañas fue isotópicamente más ligera de lo esperado para una altitud dada. Cinco eventos de gran magnitud fueron registrados durante el periodo de estudio en la cuenca de Jalovecký (Tatras Occidentales, 22.2 km2 de superficie) y la cuenca de cabecera de Škaredý (Altos Tatras, 1.4 km2 de superficie). La separación isotópica del hidrograma en dos componentes se llevó a cabo utilizando ocho opciones para el cálculo de las señales del agua de lluvia y del agua preexistente. La señal isotópica de la precipitación fue representada mediante los datos obtenidos en altitudes altas y bajas. El agua preexistente fue representada mediante el caudal previo a la crecida y mediante un valor estadístico de los datos sobre la composición isotópica del caudal tomados a largo plazo. Ambos isótopos, δ18O y δ2H, fueron utilizados para calcular las fracciones de agua de lluvia durante los picos de crecida de los eventos individuales. Estas fracciones estuvieron por debajo de 0.2-0.3 en la mayoría de los eventos. No obstante, las diferencias en el cálculo de las fracciones de agua de lluvia para diferentes composiciones isotópicas de los distintos componentes fue significativa, incluso sin tener en cuenta posibles cambios en la composición isotópica durante eventos pluviométricos individuales. El coeficiente de variación para las fracciones de agua de lluvia, calculado para las diferentes opciones, varió entre 0.14 y 0.36. Estos resultados sugieren que seguramente es más adecuado usar un rango de posibles valores en vez de un único valor a la hora de interpretar los resultados de la separación del hidrograma. La separación del hidrograma mediante 18O and 2H arrojó resultados similares
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