247 research outputs found

    New analysis method for continuous base-flow and availability of water resources based on Parallel Linear Reservoir models

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    Water flows in the hydrosphere through a tangled and tortuous labyrinth of ways that is the hydrological cycle. Flow separation models are an attempt to group such complexity of paths into a few components of flow and storage so as to reflect the overall behaviour of a basin. A new method of analysis and separation of flow components, based on equations of dynamic relations between Linear Reservoirs connected in Parallel (PLR models), is developed in this article. A synthesis of models based on mathematical filter equations is carried out in order to make comparisons with the proposed model. Reference is also made to the methodology of adjustment and calibration of the PLR models based on the recession curves of the real hydrographs. The models are tested with the continuous register of a basin located in the northeast of Spain. The simulations are carried out with two reservoir models (2R models), three reservoirs (3R models) and with a mathematical filter model to compare the results. With the results of the models, flow duration curves (FDCs) and storage duration curves (SDCs) were elaborated, thus allowing assessment of the origin of the water resources of the basin, a guarantee of their regulation and availability, the dynamic storage in the catchment, residence times and other features

    EL NUEVO DERECHO DE MARCAS (LEY 17/2001, DE 7 DE DICIEMBRE)

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    Los bienes inmateriales son creaciones intelectuales susceptibles de reproducción a través de soportes perceptibles sensorialmente que el Derecho tutela mediante atribución de derechos de uso o explotación exclusiva. (...

    Expression of LPP3 in Bergmann glia is required for proper cerebellar sphingosine-1-phosphate metabolism/signaling and development

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    Bioactive lipids serve as intracellular and extracellular mediators in cell signaling in normal and pathological conditions. Here we describe that an important regulator of some of these lipids, the lipid phosphate phosphatase-3 (LPP3), is abundantly expressed in specific plasma membrane domains of Bergmann glia (BG), a specialized type of astrocyte with key roles in cerebellum development and physiology. Mice selectively lacking expression of LPP3/Ppap2b in the nervous system are viable and fertile but exhibit defects in postnatal cerebellum development and modifications in the cytoarchitecture and arrangement of BG with a mild non-progressive motor coordination defect. Lipid and gene profiling studies in combination with pharmacological treatments suggest that most of these effects are associated with alterations in sphingosine-1- phosphate (S1P) metabolism and signaling. Altogether our data indicate that LPP3 participates in several aspects of neuron-glia communication required for proper cerebellum developmen

    Sustainability indicator for the prevention of potential thermal interferences between groundwater heat pump systems in urban aquifers

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    The steady increase of geothermal systems using groundwater is compromising the renewability of the geothermal resources in shallow urban aquifers. To ensure sustainability, scientifically-based criteria are required to prevent potential thermal interferences between geothermal systems. In this work, a management indicator (balanced sustainability index, BSI) applicable to groundwater heat pump systems is defined to assign a quantitative value of sustainability to each system, based on their intrinsic potential to produce thermal interference. The BSI indicator relies on the net heat balance transferred to the terrain throughout the year and the maximum seasonal thermal load associated. To define this indicator, 75 heating-cooling scenarios based in 23 real systems were established to cover all possible different operational conditions. The scenarios were simulated in a standard numerical model, adopted as a reference framework, and thermal impacts were evaluated. Two polynomial regression models were used for the interpolation of thermal impacts, thus allowing the direct calculation of the sustainability indicator developed as a function of heating-cooling ratios and maximum seasonal thermal loads. The BSI indicator could provide authorities and technicians with scientifically-based criteria to establish geothermal monitoring programs, which are critical to maintain the implementation rates and renewability of these systems in the cities

    Uso de compostas y vermicompostas para la producción de tomate orgánico en invernadero

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    Una alternativa en la agricultura orgánica es la utilización de sustratos orgánicos. El objetivo del presente trabajo fue evaluar el efecto de tres compostas y tres vermicompostas mezcladas en diferentes proporciones (100, 75 y 50%) con arena, sobre el rendimiento y calidad de tomate, bajo condiciones de invernadero. Se utilizó el híbrido SUN-7705 de tomate (Solanum lycopersicum L.). Los 18 tratamientos se distribuyeron en un diseño completamente al azar con arreglo factorial 6×3 con cinco repeticiones en dos fechas de siembra. Se detectaron diferencias estadísticas entre fechas de siembra (p≤0,01). Los resultados indican que las mejores siete mezclas fueron vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + tierra negra (VEMT) 75% + arena; vermicomposta de estiércol de ganado vacuno + pasto bahía (Paspalum notatum Flüggé) + tierra negra (VEPT) 100, 75 y 50% + arena; vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + tierra negra (VEMT) 50% + arena; y vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + zacate elefante (Pennisetum purpureum Schumacher; VEMZT) 100 y 75% + arena; con una media de 54,527t•ha-1. Los frutos de mayor tamaño se obtuvieron con la vermicomposta VEMT 75% + arena. El mayor contenido de sólidos solubles, se obtuvo con la mezcla VEPT 100% con 5,34ºBrix. Se concluye que se obtiene mayor rendimiento utilizando sustratos orgánicos con respecto al obtenido en producciones de tomate orgánico en campo, sin afectar la calidad del fruto

    Physical exercise as a multimodal tool for COVID-19: Could it be used as a preventive strategy?

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    Producción CientíficaThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or coronavirus disease 2019 (COVID-19) is a novel coronavirus not previously recognized in humans until late 2019. On 31 December 2019, a cluster of cases of pneumonia of unspecified etiology was reported to the World Health Organization in China. The availability of adequate SARS-CoV-2 drugs is also limited, and the efficacy and safety of these drugs for COVID-2019 pneumonia patients need to be assessed by further clinical trials. For these reasons, there is a need for other strategies against COVID-19 that are capable of prevention and treatment. Physical exercise has proven to be an effective therapy for most chronic diseases and microbial infections with preventive/therapeutic benefits, considering that exercise involves primary immunological mediators and/or anti-inflammatory properties. This review aimed to provide an insight into how the implementation of a physical exercise program against COVID-19 may be a useful complementary tool for prevention, which can also enhance recovery, improve quality of life, and provide immune protection against SARS-CoV-2 virus infection in the long term. In summary, physical exercise training exerts immunomodulatory effects, controls the viral gateway, modulates inflammation, stimulates nitric oxide synthesis pathways, and establishes control over oxidative stress

    If cooperation is likely punish mildly: Insights from economic experiments based on the snowdrift game

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    Punishment may deter antisocial behavior. Yet to punish is costly, and the costs often do not offset the gains that are due to elevated levels of cooperation. However, the effectiveness of punishment depends not only on how costly it is, but also on the circumstances defining the social dilemma. Using the snowdrift game as the basis, we have conducted a series of economic experiments to determine whether severe punishment is more effective than mild punishment. We have observed that severe punishment is not necessarily more effective, even if the cost of punishment is identical in both cases. The benefits of severe punishment become evident only under extremely adverse conditions, when to cooperate is highly improbable in the absence of sanctions. If cooperation is likely, mild punishment is not less effective and leads to higher average payoffs, and is thus the much preferred alternative. Presented results suggest that the positive effects of punishment stem not only from imposed fines, but may also have a psychological background. Small fines can do wonders in motivating us to chose cooperation over defection, but without the paralyzing effect that may be brought about by large fines. The later should be utilized only when absolutely necessary.Comment: 15 pages, 6 figures; accepted for publication in PLoS ON

    La modelización tridimensional del flujo del agua subterránea y transporte de calor en la gestión de recursos geotérmicos someros en zonas urbanas

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    La planificación del uso geotérmico del agua subterránea en acuíferos someros urbanos requiere un modelo numérico capaz de reproducir los efectos de la explotación actual y ser capaz de predecir los impactos derivados de dicha actividad. En este trabajo se presenta el desarrollo preliminar de un modelo numérico que puede contribuir a mejorar la gestión de los recursos geotérmicos someros en la ciudad de Zaragoza. El modelo numérico permite implementar toda la información hidrogeológica y térmica recopilada, explicar esta información de forma coherente reproduciendo la física de fluidos y termodinámica en medios poroso s y predecir a medio y largo plazo los impactos producidos. Finalmente se muestran las posibilidades y ventajas derivadas del uso del modelo numérico en la gestión de permisos de concesión de derechos de explotación para nuevos aprovechamientos. The management of the thermal use of groundwater in shallow urban aquifers requires a numerical model capable of reproducing the impacts of actual exploitations and of predicting further impacts in the future. In this work, the numerical model developed for the management of shallow geothermal resources in the city of Zaragoza (Spain) is presented. The model allows to explain the data coherent with the fluid physics and the heat transport in porous media and also provide predictions for the thermal impacts at mid- and long-term. Finally, the possibilities and advantages derived from the use of the numerical modelling for the concession process of new exploitation licenses are described

    Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants

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    [EN] Generation units connected to the grid are currently required to meet low-voltage ride-through (LVRT) requirements. In most developed countries, these requirements also apply to renewable sources, mainly wind power plants and photovoltaic installations connected to the grid. This study proposes an alternative characterisation solution to classify and visualise a large number of collected events in light of current limits and requirements. The authors' approach is based on linearised root-mean-square-(RMS)-voltage trajectories, taking into account LRVT requirements, and a clustering process to identify the most likely pattern trajectories. The proposed solution gives extensive information on an event's severity by providing a simple but complete visualisation of the linearised RMS-voltage patterns. In addition, these patterns are compared to current LVRT requirements to determine similarities or discrepancies. A large number of collected events can then be automatically classified and visualised for comparative purposes. Real disturbances collected from renewable sources in Spain are used to assess the proposed solution. Extensive results and discussions are also included in this study.The authors thank the financial support from the 'Ministerio de Economia y Competitividad' (Spain) and the European Union - ENE2016-78214-C2-2-R, Fulbright/Spanish Ministry of Education Visiting Scholar - PRX14/00694. This work was also supported by the US Department of Energy under contract no. DE-AC36-08-GO28308 with the National Renewable Energy LaboratoryGarcía-Sánchez, TM.; Gómez-Lázaro, E.; Muljadi, E.; Kessler, M.; Muñoz-Benavente, I.; Molina-García, A. (2018). Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants. IET Generation Transmission & Distribution. 12(6):1256-1262. https://doi.org/10.1049/iet-gtd.2017.0474S12561262126Craciun B. Kerekes T. 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    Maximal care considerations when treating patients with end-stage heart failure: ethical and procedural quandaries in management of the very sick

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    Deciding who should receive maximal technological treatment options and who should not represents an ethical, moral, psychological and medico-legal challenge for health care providers. Especially in patients with chronic heart failure, the ethical and medico-legal issues associated with providing maximal possible care or withholding the same are coming to the forefront. Procedures, such as cardiac transplantation, have strict criteria for adequate candidacy. These criteria for subsequent listing are based on clinical outcome data but also reflect the reality of organ shortage. Lack of compliance and non-adherence to lifestyle changes represent relative contraindications to heart transplant candidacy. Mechanical circulatory support therapy using ventricular assist devices is becoming a more prominent therapeutic option for patients with end-stage heart failure who are not candidates for transplantation, which also requires strict criteria to enable beneficial outcome for the patient. Physicians need to critically reflect that in many cases, the patient’s best interest might not always mean pursuing maximal technological options available. This article reflects on the multitude of critical issues that health care providers have to face while caring for patients with end-stage heart failure
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