807 research outputs found
Biodiversity and Ecosystem Health of the Aldabra Group, Southern Seychelles: Scientific Report to the Government of Seychelles.
National Geographic's Pristine Seas project, in collaboration with the government of the Seychelles, the Island Conservation Society (ICS), the Seychelles Islands Foundation (SIF), and the Waitt Foundation, conducted an expedition to explore the poorly known marine environment around these islands. The goals were to assess the biodiversity of the nearshore marine environment and to survey the largely unknown deep sea realm. The data collected contribute to the marine spatial planning of the Seychelles, in particular the creation of large marine reserves
Bruja, brujo, hechicera, hechicero, sorgin como insultos en la Navarra de los siglos XVI y XVII
Enhanced Viral Activity in the Surface Microlayer of the Arctic and Antarctic Oceans
The ocean surface microlayer (SML), with physicochemical characteristics different from those of subsurface waters (SSW), results in dense and active viral and microbial communities that may favor virus–host interactions. Conversely, wind speed and/or UV radiation could adversely affect virus infection. Furthermore, in polar regions, organic and inorganic nutrient inputs from melting ice may increase microbial activity in the SML. Since the role of viruses in the microbial food web of the SML is poorly understood in polar oceans, we aimed to study the impact of viruses on prokaryotic communities in the SML and in the SSW in Arctic and Antarctic waters. We hypothesized that a higher viral activity in the SML than in the SSW in both polar systems would be observed. We measured viral and prokaryote abundances, virus-mediated mortality on prokaryotes, heterotrophic and phototrophic nanoflagellate abundance, and environmental factors. In both polar zones, we found small differences in environmental factors between the SML and the SSW. In contrast, despite the adverse effect of wind, viral and prokaryote abundances and virus-mediated mortality on prokaryotes were higher in the SML than in the SSW. As a consequence, the higher carbon flux released by lysed cells in the SML than in the SSW would increase the pool of dissolved organic carbon (DOC) and be rapidly used by other prokaryotes to grow (the viral shunt). Thus, our results suggest that viral activity greatly contributes to the functioning of the microbial food web in the SML, which could influence the biogeochemical cycles of the water columnEn prensa
Obstrucción por cuerpos extraños localizados en esófago : terapéutica endoscópica. Tres casos clínicos
Se presentan tres casos clínicos de obstrucción esofágica por cuerpos extraños en posición precardial que son extraídos por técnica endoscópica con fibroencloscopio flexible.Three clinical cases of oesophagus obstruction due to foreign bodies in precardial position are described. These-foreign bodies have been removed by endoscopical technic with flexible fiberscope
Microbially-Mediated Fluorescent Organic Matter Transformations in the Deep Ocean. Do the chemical precursors matter?
Original research paperThe refractory nature of marine dissolved organic matter (DOM) increases while it travels from surface waters to the deep ocean. This resistant fraction is in part composed of fluorescent humic-like material, which is relatively difficult to metabolize by deep water prokaryotes, and it can also be generated by microbial activity. It has been recently argued that microbial production of new fluorescent DOM (FDOM) requires the presence of humic precursors in the surrounding environment. In order to experimentally test how the chemical quality of the available organic compounds influences the production of new FDOM, three experiments were performed with bathypelagic Atlantic waters. Microbial communities were incubated in three treatments which differed in the quality of the organic compounds added: (i) glucose and acetate; (ii) glucose, acetate, essential amino acids, and humic acids; and (iii) humic acids alone. The response of the prokaryotes and the production of FDOM were simultaneously monitored. Prokaryotic abundance was highest in treatments where labile compounds were added. The rate of humic-like fluorescence production, scaled to prokaryotic abundance, varied depending on the quality of the additions. The precursor compounds affected the generation of new humic-like FDOM, and the cell-specific production of this material was higher in the incubations amended with humic precursors. Furthermore, we observed that the protein-like fluorescence decreased only when fresh amino acids were added. These findings contribute to the understanding of FDOM variability in deep waters and provide valuable information for studies where fluorescent compounds are used in order to track water masses and/or microbial processes.Spanish Ministry of Economy and Competitivity, CSIC, ESF and Danish Research Council for Independent ResearchVersión del edito
Tuning the current ratio of a CPV system to maximize the energy harvesting in a particular location
A method based on experimental data is proposed to optimize the energy harvesting of a silicone-on-glass Fresnel-lens based CPV system. It takes into account the spectral variations along the year in a particular location as well as the thermal and spectral sensitivities of the optics and solar cell. In addition, different alternatives to tune the top/middle subcells current ratio in a CPV module are analyzed and their capacity to maximize the annually produced energy is quantified
Optimising Test Environment and Test Set Up for Characterizing Actual Thermal Performance of Building Components and Whole Buildings
The development of mathematical models that can reliably simulate the energy performance of a whole building or a building component with minimal discrepancy between the real and simulated data is a major aim of Building Physics science. In order to create models that accurately represent real physical phenomena it is necessity to perform tests on buildings and building components, producing real data that can be used to adjust and validate these models. If these tests are not undertaken correctly, incorrect data sets, insufficient data sets or excessively complex and expensive experiments may be performed. Thus, depending on the aim and the accuracy needed for the mathematical models, the test environment and test set up must be chosen correctly. This problem has been studied inside Subtask 2 of the Annex58 “Reliable building energy performance characterisation based on full scale dynamic measurements”. The aim was to come to a roadmap on how to measure the actual thermal performance of building components and whole buildings. This means under realistic boundary conditions (field exposure or artificial climate) and taking into account workmanship. Since there are many established methods and different Standards for different measurement purposes, the solution has been to organize the existing methods (both Standards and widely used non-Standard testing methods) into a decision tree. This decision tree begins with the question “What do you want to characterize?” and determines the context, environment, experimental design and analysis method being used by the user, terminating in a document reference. In a very simple format, following the decision tree and having a clear idea of what you need to characterize or model, you will reach an end branch of the decision tree where a testing Standard or testing method will be defined. The objective of this paper is to present the decision tree, its logic and the way it should be used
Análisis de las predicciones climáticas a partir de distintos servicios climáticos para la programación del riego
Comunicación presentada al XXXVII Congreso Nacional de Riegos, celebrado en Don Benito del 4 al 6 de Junio de 2019 y organizada por la Asociación Española de Riegos y Drenajes y la Universidad de ExtremaduraEl objetivo del estudio es analizar la precisión de los servicios climáticos disponibles mediante su comparación con los datos reales registrados, y mejorar su estimación para el cálculo de la ETo a la hora de efectuar la programación del riego a corto plazo.Generalitat Valenciana, Consellería de Educación, Investigación, Cultura y Deportes: Proyecto AICO 201
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