116 resultados para Rapa Nui


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The observed changes in physical properties of sea ice such as decreased thickness and increased melt pond cover severely impact the energy budget of Arctic sea ice. Increased light transmission leads to increased deposition of solar energy in the upper ocean and thus plays a crucial role for amount and timing of sea-ice-melt and under-ice primary production. Recent developments in underwater technology provide new opportunities to study light transmission below the largely inaccessible underside of sea ice. We measured spectral under-ice radiance and irradiance using the new Nereid Under-Ice (NUI) underwater robotic vehicle, during a cruise of the R/V Polarstern to 83°N 6°W in the Arctic Ocean in July 2014. NUI is a next generation hybrid remotely operated vehicle (H-ROV) designed for both remotely piloted and autonomous surveys underneath land-fast and moving sea ice. Here we present results from one of the first comprehensive scientific dives of NUI employing its interdisciplinary sensor suite. We combine under-ice optical measurements with three dimensional under-ice topography (multibeam sonar) and aerial images of the surface conditions. We investigate the influence of spatially varying ice-thickness and surface properties on the spatial variability of light transmittance during summer. Our results show that surface properties such as melt ponds dominate the spatial distribution of the under-ice light field on small scales (<1000 m**2), while sea ice-thickness is the most important predictor for light transmission on larger scales. In addition, we propose the use of an algorithm to obtain histograms of light transmission from distributions of sea ice thickness and surface albedo.

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The present data set was used as a training set for a Habitat Suitability Model. It contains occurrence (presence-only) of living Lophelia pertusa reefs in the Irish continental margin, which were assembled from databases, cruise reports and publications. A total of 4423 records were inspected and quality assessed to ensure that they (1) represented confirmed living L. pertusa reefs (so excluding 2900 records of dead and isolated coral colony records); (2) were derived from sampling equipment that allows for accurate (<200 m) geo-referencing (so excluding 620 records derived mainly from trawling and dredging activities); and (3) were not duplicated. A total of 245 occurrences were retained for the analysis. Coral observations are highly clustered in regions targeted by research expeditions, which might lead to falsely inflated model evaluation measures (Veloz, 2009). Therefore, we coarsened the distribution data by deleting all but one record within grid cells of 0.02° resolution (Davies & Guinotte 2011). The remaining 53 points were subject to a spatial cross-validation process: a random presence point was chosen, grouped with its 12 closest neighbour presence points based on Euclidean distance and withheld from model training. This process was repeated for all records, resulting in 53 replicates of spatially non-overlapping sets of test (n=13) and training (n=40) data. The final 53 occurrence records were used for model training.

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This paper reports the effects produced on the organisms of the soil (plants, invertebrates and microorganisms), after the application of two types of poultry manure (sawdust and straw bed) on an agricultural land. The test was made using a terrestrial microcosm, Multi-Species Soil System (MS3) developed in INIA. There was no difference in the germination for any of the three species of plants considered in the study. The biomass was increased in the wheat (Triticum aestivum) coming from ground treated with both kinds of poultry manure. Oilseed rape (Brasica rapa) was not affected and regarding vetch (Vicia sativa) only straw poultry manure showed significant difference. For length only Vicia sativa was affected showing a reduction when straw was exposed to poultry manure. When the effect on invertebrates was studied, we observed a reduction in the number of worms during the test, especially from the ground control (13.7%), higher than in the ground with sawdust poultry manure (6.7%), whereas in the ground with straw poultry manure, there was no reduction. The biomass was affected and at the end of the test it was observed that while the reduction of worms in the ground control was about 48%, the number of those that were in the ground with sawdust poultry manure or straw poultry manure decreased by 41% and 22% respectively. Finally, the effects on microorganisms showed that the enzymatic activities: dehydrogenase (DH) and phosphatase and basal respiration rate increased at the beginning of the test, and the differences were statistically significant compared with the values of the control group. During the test, all these parameters decreased (except DH activities) but they were always higher than in the ground control. This is why it is possible to deduce that the contribution of poultry manure caused an improvement in the conditions of fertilization and also for the soil.

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A la hora de afrontar un proyecto de investigación, no basta con una vigilancia tradicional del entorno. Ya que debido a lo cambiante del mundo, a la globalización, a lo rápido que se desarrollan nuevas tecnologías y productos es preciso realizar un proceso sistemático que permita a las organizaciones o empresas anticiparse a los cambios tecnológicos. En este contexto, el diseño de metodologías basadas en la Vigilancia Tecnológica (VT) permite gestionar la actividad innovadora de organizaciones o empresas facilitando el proceso de generación de ideas para el desarrollo de productos o servicios. Es por ello que en este Proyecto de Fin de Grado se ha diseñado una estrategia para aplicar metodologías de Vigilancia Tecnológica aplicadas a un proyecto de I+D que estudia las Interfaces Naturales de Usuario (NUI). Para ello se ha partido de la metodología de trabajo basada en el proceso de Vigilancia Tecnológica e Inteligencia Competitiva del proyecto CETISME, identificando claramente cada una de las fases que lo componen: identificación de objetivos, selección de las fuentes de información, búsqueda y almacenamiento de la información, análisis de la información y por último validación de la información que concluye con la creación de informes de Vigilancia Tecnológica. Por lo tanto, para cada una de las fases que componen lo que comúnmente se llama el ciclo de la vigilancia, se ha explicado en primer lugar en qué consisten, que estrategias a seguir son las más adecuadas así como la manera de llevarlas a cabo, y por último, si fuera necesario, qué herramientas (desde bases de datos a software) son necesarias o son de utilidad para llevar a cabo el proceso y optimizarlo. De esta manera, como se verá a lo largo de este documento, la aplicación de dicha metodología permitirá a las organizaciones o empresas obtener situaciones ventajosas a la hora de innovar, captar oportunidades o detectar amenazas, identificar competidores o alianzas potenciales, entre otros. ABSTRACT. When taking over a research project, a traditional surveillance of the environment is not enough. Mainly due to the changing the world, to the globalization, to how fast new technologies and products are developed, is necessary to make a systematic process that enables organizations or companies anticipate to technological changes. In this context, the design of methodologies based on the Technology Watch (TW) allows managing the innovative activity of organizations or companies facilitating the process of generating ideas for products or services development. For this reason, in this Thesis a strategy for applying Technological Watch methodologies applied to a R&D project studying Natural User Interfaces (NUI) has been designed. To achieve this goal, the starting point was the CETISME project methodologies, which are based on the Technology Watch and the Competitive Intelligence process, clearly identifying each of the phases that compose it: identification of objectives, selection of the information sources, storage, search and analysis of the information, and finally validating the information that concludes with the creation of Technological Watch reports. Therefore, for each of the phases composing what is commonly known as the monitoring cycle, it has been explained in first place what they consist of, what strategies are more adequate as well as how they should be implemented, and finally, if necessary, what tools (from databases to software) are needed or are useful for managing the process and optimize it. Thus, as discussed throughout this document, the application of said methodology will allow organizations or companies to obtain advantageous situations when it comes to innovate, catch opportunities or detect threats, to identify competitors or potential alliances, among others.

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Auxin plays an important role in many aspects of plant development including stress responses. Here we briefly summarize how auxin is involved in salt stress, drought (i.e. mostly osmotic stress), waterlogging and nutrient deficiency in Brassica plants. In addition, some mechanisms to control auxin levels and signaling in relation to root formation (under stress) will be reviewed. Molecular studies are mainly described for the model plant Arabidopsis thaliana, but we also like to demonstrate how this knowledge can be transferred to agriculturally important Brassica species, such as Brassica rapa, Brassica napus and Brassica campestris. Moreover, beneficial fungi could play a role in the adaptation response of Brassica roots to abiotic stresses. Therefore, the possible influence of Piriformospora indica will also be covered since the growth promoting response of plants colonized by P. indica is also linked to plant hormones, among them auxin.

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The phosphorelay signal transduction system activates developmental transcription in sporulation of Bacillus subtilis by phosphorylation of aspartyl residues of the Spo0F and Spo0A response regulators. The phosphorylation level of these response regulators is determined by the opposing activities of protein kinases and protein aspartate phosphatases that interpret positive and negative signals for development in a signal integration circuit. The RapA protein aspartate phosphatase of the phosphorelay is regulated by a peptide that directly inhibits its activity. This peptide is proteolytically processed from an inactive pre-inhibitor protein encoded in the phrA gene. The pre-inhibitor is cleaved by the protein export apparatus to a putative pro-inhibitor that is further processed to the active inhibitor peptide and internalized by the oligopeptide permease. This export–import circuit is postulated to be a mechanism for timing phosphatase activity where the processing enzymes regulate the rate of formation of the active inhibitor. The processing events may, in turn, be controlled by a regulatory hierarchy. Chromosome sequencing has revealed several other phosphatase–prepeptide gene pairs in B. subtilis, suggesting that the use of this mechanism may be widespread in signal transduction.

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Insulin negatively regulates expression of the insulin-like growth factor binding protein 1 (IGFBP-1) gene by means of an insulin-responsive element (IRE) that also contributes to glucocorticoid stimulation of this gene. We find that the Caenorhabditis elegans protein DAF-16 binds the IGFBP-1⋅IRE with specificity similar to that of the forkhead (FKH) factor(s) that act both to enhance glucocorticoid responsiveness and to mediate the negative effect of insulin at this site. In HepG2 cells, DAF-16 and its mammalian homologs, FKHR, FKHRL1, and AFX, activate transcription through the IGFBP-1⋅IRE; this effect is inhibited by the viral oncoprotein E1A, but not by mutants of E1A that fail to interact with the coactivator p300/CREB-binding protein (CBP). We show that DAF-16 and FKHR can interact with both the KIX and E1A/SRC interaction domains of p300/CBP, as well as the steroid receptor coactivator (SRC). A C-terminal deletion mutant of DAF-16 that is nonfunctional in C. elegans fails to bind the KIX domain of CBP, fails to activate transcription through the IGFBP-1⋅IRE, and inhibits activation of the IGFBP-1 promoter by glucocorticoids. Thus, the interaction of DAF-16 homologs with the KIX domain of CBP is essential to basal and glucocorticoid-stimulated transactivation. Although AFX interacts with the KIX domain of CBP, it does not interact with SRC and does not respond to glucocorticoids or insulin. Thus, we conclude that DAF-16 and FKHR act as accessory factors to the glucocorticoid response, by recruiting the p300/CBP/SRC coactivator complex to an FKH factor site in the IGFBP-1 promoter, which allows the cell to integrate the effects of glucocorticoids and insulin on genes that carry this site.