877 resultados para SPENT FUEL ELEMENTS
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Rare earth elements (REE) and stable isotope compositions (delta C-13 and delta O-18) of shark teeth and phosphatic coprolites were analyzed from the Lower Maastrichtian layers of the El Haria Formation and two sequences of the Paleocene-Eocene (P/E) Chouabine Formation in the Gafsa Basin (south western of Tunisia) in order to trace the sedimentological, climatic and oceanographic conditions. The REE chemistry and their distribution in the two archives are the same for each of the studied layers indicating that the coprolites and shark teeth experienced the same early diagenetic environments. However major differences occur between the Maastrichtian and the P/E reflecting changes in the depositional conditions. The Early Maastrichtian burial environment tended to be more anoxic with REE derived from reduced FeO. While in the P/E the REE patterns mimic the modern oxic-suboxic seawater, the REE source from remineralisation of organic coating could have more significance. The oxygen isotope compositions of the structural phosphates (delta O-18(PO4)) indicate a stable and warm climate during both studied time intervals. A small offset (-0.4 parts per thousand) in the delta O-18 value between the coprolites and shark teeth show minor thermal gradient between bottom and surface water. The pronounced negative shift of 34%. in delta C-13 values recorded in the upper part of the Chouabine Formation was ascribed to the Paleocene-Eocene boundary. At the same time the lack of negative change in the delta O-18 is explained by the semi-closed situation of the Gafsa Basin, which situation also played an important role in the evolution of the organic matters in the sediment resulting in the exceptional low delta C-13 values. (C) 2008 Elsevier B.V. All rights reserved.
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Chagas disease, named after Carlos Chagas who first described it in 1909, exists only on the American Continent. It is caused by a parasite, Trypanosoma cruzi, transmitted to humans by blood-sucking triatomine bugs and by blood transfusion. Chagas disease has two successive phases, acute and chronic. The acute phase lasts 6 to 8 weeks. After several years of starting the chronic phase, 20% to 35% of the infected individuals, depending on the geographical area will develop irreversible lesions of the autonomous nervous system in the heart, esophagus, colon and the peripheral nervous system. Data on the prevalence and distribution of Chagas disease improved in quality during the 1980's as a result of the demographically representative cross-sectional studies carried out in countries where accurate information was not available. A group of experts met in Brasília in 1979 and devised standard protocols to carry out countrywide prevalence studies on human T. cruzi infection and triatomine house infestation. Thanks to a coordinated multi-country program in the Southern Cone countries the transmission of Chagas disease by vectors and by blood transfusion has been interrupted in Uruguay in1997, in Chile in 1999, and in 8 of the 12 endemic states of Brazil in 2000 and so the incidence of new infections by T. cruzi in the whole continent has decreased by 70%. Similar control multi-country initiatives have been launched in the Andean countries and in Central America and rapid progress has been recorded to ensure the interruption of the transmission of Chagas disease by 2005 as requested by a Resolution of the World Health Assembly approved in 1998. The cost-benefit analysis of the investments of the vector control program in Brazil indicate that there are savings of US$17 in medical care and disabilities for each dollar spent on prevention, showing that the program is a health investment with good return. Since the inception in 1979 of the Steering Committee on Chagas Disease of the Special Program for Research and Training in Tropical Diseases of the World Health Organization (TDR), the objective was set to promote and finance research aimed at the development of new methods and tools to control this disease. The well known research institutions in Latin America were the key elements of a world wide network of laboratories that received - on a competitive basis - financial support for projects in line with the priorities established. It is presented the time line of the different milestones that were answering successively and logically the outstanding scientific questions identified by the Scientific Working Group in 1978 and that influenced the development and industrial production of practical solutions for diagnosis of the infection and disease control.
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This booklet developed by safefood inpartnership with the Irish Nutrition and Dietetic Institute (INDI) in the Republic of Ireland and the British Dietetic Association in Northern Ireland, provides general advice for 13- to 17-year-olds who are involved in sport.
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Evidence Review 7 - Tackling fuel poverty and cold home-related health problems Briefing 7 - Fuel poverty and cold home-related health problems This pair of documents, commissioned by Public Health England, and written by the UCL Institute of Health Equity, address the health impacts of fuel poverty and cold homes. These documents provide an overview of fuel poverty, describing the evidence linking fuel poverty, cold homes, and poor health outcomes. They examine the scale of the problem across England and trends over time. Evidence shows that living in cold homes is associated with poor health outcomes and an increased risk of morbidity and mortality for all age groups. The documents also provide a brief overview of national policy and sets out the role of local authorities and potential interventions at local level. Fuel poverty is not just about poverty, but also about the quality of England’s housing stock and energy efficiency. The review discusses some of the interventions that have been implemented at the local level to help people on low incomes during cold weather and to address cold home-related health problems. The full evidence review and a shorter summary briefing are available to download above. This document is part of a series. An overview document which provides an introduction to this and other documents in the series, and links to the other topic areas, is available on the ‘Local Action on health inequalities’ project page. A video of Michael Marmot introducing the work is also available on our videos page.
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Aquest treball és una introducció als sistemes d'informació geogràfica, que consisteix en una breu descripció dels aspectes fonamentals dels sistemes d'informació geogràfica i en la creació d'una base de dades dels elements d'una xarxa de distribució d'aigua potable.
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The Xenopus vitellogenin (vit) gene B1 estrogen-inducible enhancer is formed by two closely adjacent 13 bp imperfect palindromic estrogen-responsive elements (EREs), i.e. ERE-2 and ERE-1, having one and two base substitutions respectively, when compared to the perfect palindromic consensus ERE (GGTCANNNTGACC). Gene transfer experiments indicate that these degenerated elements, on their own, have a low or no regulatory capacity at all, but in vivo act together synergistically to confer high receptor- and hormone-dependent transcription activation to the heterologous HSV thymidine kinase promoter. Thus, the DNA region upstream of the vitB1 gene comprising these two imperfect EREs separated by 7 bp, was called the vitB1 estrogen-responsive unit (vitB1 ERU). Using in vitro protein-DNA interaction techniques, we demonstrate that estrogen receptor dimers bind cooperatively to the imperfect EREs of the vitB1 ERU. Binding of a first receptor dimer to the more conserved ERE-2 increases approximately 4- to 8-fold the binding affinity of the receptor to the adjacent less conserved ERE-1. Thus, we suggest that the observed synergistic estrogen-dependent transcription activation conferred by the pair of hormone-responsive DNA elements of the vit B1 ERU is the result of cooperative binding of two estrogen receptor dimers to these two adjacent imperfect EREs.
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The ENCyclopedia Of DNA Elements (ENCODE) Project aims to identify all functional elements in the human genome sequence. The pilot phase of the Project is focused on a specified 30 megabases (approximately 1%) of the human genome sequence and is organized as an international consortium of computational and laboratory-based scientists working to develop and apply high-throughput approaches for detecting all sequence elements that confer biological function. The results of this pilot phase will guide future efforts to analyze the entire human genome.
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S'ha aprofundit en el camp de l'atenció a la diversitat que reben, i que poden rebre, els adolescents que fracassen en l'escolaritat reglada. Es fa un estudi de 4 unitats d'escolarització compartida i unes pràctiques a la Unitat Mèdico-Educativa de Sant Boi. Es plantegen alternatives per tal d'afavorir l'assessorament d'aquest centre i per a donar una bona resposta educativa a aquests alumnes en edat crítica.
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A Espanya encara tenim pendent la transposició de la Directiva 2001/29/CE "relativa a la armonización de determinados aspectos de los derechos de autor y derechos afines a los derechos de autor en la sociedad de la información", la qual suposarà una modificació del marc legal que regula aquesta matèria. En aquest article s'analitzen els aspectes de la Directiva que més poden afectar el desenvolupament dels serveis que ofereixen les biblioteques i centres similars, prestant atenció als punts que poden ser més conflictius a la llum de les dues propostes que fins al moment s'han plantejat.
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Chagas disease, named after Carlos Chagas, who first described it in 1909, exists only on the American Continent. It is caused by a parasite, Trypanosoma cruzi, which is transmitted to humans by blood-sucking triatomine bugs and via blood transfusion. Chagas disease has two successive phases: acute and chronic. The acute phase lasts six-eight weeks. Several years after entering the chronic phase, 20-35% of infected individuals, depending on the geographical area, will develop irreversible lesions of the autonomous nervous system in the heart, oesophagus and colon, and of the peripheral nervous system. Data on the prevalence and distribution of Chagas disease improved in quality during the 1980s as a result of the demographically representative cross-sectional studies in countries where accurate information was not previously available. A group of experts met in Brasilia in 1979 and devised standard protocols to carry out countrywide prevalence studies on human T. cruzi infection and triatomine house infestation. Thanks to a coordinated multi-country programme in the Southern Cone countries, the transmission of Chagas disease by vectors and via blood transfusion was interrupted in Uruguay in 1997, in Chile in 1999 and in Brazil in 2006; thus, the incidence of new infections by T. cruzi across the South American continent has decreased by 70%. Similar multi-country initiatives have been launched in the Andean countries and in Central America and rapid progress has been reported towards the goal of interrupting the transmission of Chagas disease, as requested by a 1998 Resolution of the World Health Assembly. The cost-benefit analysis of investment in the vector control programme in Brazil indicates that there are savings of US$17 in medical care and disabilities for each dollar spent on prevention, showing that the programme is a health investment with very high return. Many well-known research institutions in Latin America were key elements of a worldwide network of laboratories that carried out basic and applied research supporting the planning and evaluation of national Chagas disease control programmes. The present article reviews the current epidemiological trends for Chagas disease in Latin America and the future challenges in terms of epidemiology, surveillance and health policy.
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L'objectiu d'aquest projecte és el disseny dels bancs d'assaig necessaris per poder realitzar tres assajos de fisuració i deformació diferida al laboratori de resistència de materials de la UdGsobre provetes i bigues de formigó armat amb FRP i estudiar- ne el comportament. El primer assaig és el de fluència del formigó, on es sotmet una proveta a una compressió mantinguda en el temps. El segon assaig és un de tracció directa, on s'aplica una càrrega a tracció mantinguda en el temps en una proveta de formigó armat amb una barra FRP de reforç intern. El tercer és un assaig a flexió, on es carregarà una biga a flexió durant un període llarg de temps
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Actualment l’esport del rem només s’entén com a activitat de lleure o esport de competició.Dins del rem, hi ha una gran varietat de disciplines esportives; totes coincideixen en l’impuls d’una embarcació mitjançant un sistema de palanques simple. Es diferencien en dos grans grups: el banc mòbil i el banc fix. El banc mòbil disposa d’un seient sobre rodes que permet aprofitar la força de les cames per la impulsió, en canvi, en el banc fix, no hi ha desplaçament del seient, el que implica el treball del tors i braços. Un dels punts que tenen en comú tot el banc fix, és el disseny del seu rem; a diferènciadel banc mòbil on la pala pot tenir el disseny que es vulgui. En banc fix la pala del rem ha de ser simètrica i alineada amb la canya del rem. L’objectiu d’aquest projecte és l’anàlisi hidrodinàmic de diferents models de pales simètriques per tal de determinar el model més eficient, des del punt de vista hidrodinàmic, per a la impulsió de l’embarcació de banc fix. Així, es simularan virtualment diferents models de pales simètriques disponibles en el mercat com models prototipus amb un programa de dinàmica de fluids computacional. L’anàlisi dels resultats determinarà el model més eficient. En la realització del projecte, l’estudi hidrodinàmic es realitzarà de manera virtual a partir de la utilització de programes comercials de dinàmica de fluids. Així com també programes de disseny 3D i programes de mallat que siguin compatibles amb el programa de simulació a utilitzar. En el disseny s’utilitzaran programes com Autocad i Rhinoceros, després, en funció del disseny, utilitzarem un programa d’elements finits anomenat ICEM ANSYS que mallarà la geometria emprada. Finalment, la simulació s’efectuarà amb el programa ANSYS CFX. L’estudi no preveu el càlcul de resistència mecànica dels models ni la seva construcció
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Empirical studies have recently pointed towards a socio-structural category largely overlooked in social inequality research: the dynamic positions of households adjacent to those of the poor and yet not representing those of the established, more prosperous positions in society. These results suggest that the population in this category fluctuates into and out of poverty more often than moving into and out of secure prosperity. This category - still lacking theoretical conceptualization - is characterized by both precariousness and a certain degree of prosperity; despite a restricted and uncertain living standard it holds a range of opportunities for action. We seek analytical elements to conceptualize 'precarious prosperity' for comparative empirical research by subjecting various concepts of social inequality research to critical scrutiny. We then operationally define 'precarious prosperity' to screen for this population in three countries. Based on qualitative interviews with households in precarious prosperity, we present first analyses of perceptions and household strategies that underline the relevance of the concept in different countries.
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Trypanosoma cruzi, a protozoan parasite that causes Chagas disease, exhibits unique mechanisms for gene expression such as constitutive polycistronic transcription of protein-coding genes, RNA editing and trans-splicing. In the absence of mechanism controlling transcription initiation, organized subsets of T. cruzi genes must be post-transcriptionally co-regulated in response to extracellular signals. The mechanisms that regulate stage-specific gene expression in this parasite have become much clearer through sequencing its whole genome as well as performing various proteomic and microarray analyses, which have demonstrated that at least half of the T. cruzi genes are differentially regulated during its life cycle. In this review, we attempt to highlight the recent advances in characterising cis and trans-acting elements in the T. cruzi genome that are involved in its post-transcriptional regulatory machinery.