959 resultados para Casting atmosphere
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Deduction allows us to draw consequences from previous knowledge. Deductive reasoning can be applied to several types of problem, for example, conditional, syllogistic, and relational. It has been assumed that the same cognitive operations underlie solutions to them all; however, this hypothesis remains to be tested empirically. We used event-related fMRI, in the same group of subjects, to compare reasoning-related activity associated with conditional and syllogistic deductive problems. Furthermore, we assessed reasoning-related activity for the two main stages of deduction, namely encoding of premises and their integration. Encoding syllogistic premises for reasoning was associated with activation of BA 44/45 more than encoding them for literal recall. During integration, left fronto-lateral cortex (BA 44/45, 6) and basal ganglia activated with both conditional and syllogistic reasoning. Besides that, integration of syllogistic problems additionally was associated with activation of left parietal (BA 7) and left ventro-lateral frontal cortex (BA 47). This difference suggests a dissociation between conditional and syllogistic reasoning at the integration stage. Our finding indicates that the integration of conditional and syllogistic reasoning is carried out by means of different, but partly overlapping, sets of anatomical regions and by inference, cognitive processes. The involvement of BA 44/45 during both encoding (syllogisms) and premise integration (syllogisms and conditionals) suggests a central role in deductive reasoning for syntactic manipulations and formal/linguistic representations.
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A brief summary is given here about some of the geochemical methodologies that are often used to obtain information from fossils and sediments about the past environment. Such methods are frequently applied in our project in which the formation of Paleogene phosphate sequences in North Africa is investigated. These layers were deposited in shallow marine seas during a period of extreme warm climate with a high CO(2) concentration in the atmosphere. Some of the characteristics of this greenhouse interval are similar to the modern anthropogenic situation hence it is intensively investigated from several aspects by many scientists. Here the geochemical compositions of fossils deposited during this time are discussed, focusing on how the data are obtained and how they could be evaluated in terms of palaeo-environmental conditions.
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The classical description of Si oxidation given by Deal and Grove has well-known limitations for thin oxides (below 200 Ã). Among the large number of alternative models published so far, the interfacial emission model has shown the greatest ability to fit the experimental oxidation curves. It relies on the assumption that during oxidation Si interstitials are emitted to the oxide to release strain and that the accumulation of these interstitials near the interface reduces the reaction rate there. The resulting set of differential equations makes it possible to model diverse oxidation experiments. In this paper, we have compared its predictions with two sets of experiments: (1) the pressure dependence for subatmospheric oxygen pressure and (2) the enhancement of the oxidation rate after annealing in inert atmosphere. The result is not satisfactory and raises serious doubts about the model’s correctness
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Luster is a metal glass nanocomposite layer first produced in the Middle East in early Islamic times ( 9th AD) made of metal copper or silver nanoparticles embedded in a silica-based glassy matrix. These nanoparticles are produced by ion exchange between Cu+ and Ag+ and alkaline ions from the glassy matrix and further growth in a reducing atmosphere. The most striking property of luster is its capability of reflecting light like a continuous metal layer and it was unexpectedly found to be linked to one single production parameter: the presence of lead in the glassy matrix composition. The purpose of this article is to describe the characteristics and differences of the nanoparticle layers developed on lead rich and lead free glasses. Copper luster layers obtained using the ancient recipes and methods are analyzed by means of elastic ion backscattering spectroscopy associated with other analytical techniques. The depth profile of the different elements is determined, showing that the luster layer formed in lead rich glasses is 5–6 times thinner and 3–4 times Cu richer. Therefore, the metal nanoparticles are more densely packed in the layer and this fact is related to its higher reflectivity. It is shown that lead influences the structure of the metal nanoparticle layer through the change of the precipitation kinetics
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Spectators play a fundamental role in sports events because they co-create value with the athletes, and they can provide substantial revenues for the organisers. This is even more the case for the Olympic Games, as was strikingly illustrated by London 2012. Although most people see the Games on television, the Olympics need large numbers of flesh-and-blood spectators and fans to encourage and applaud the Olympians and to create the festive atmosphere that is such an important part of Olympic competitions. Spectators can transform simple sporting competitions between athletes into spectacles that generate strong emotions. In the arena provided by the organisers, they create with the athletes an event that is worthy of being reported by the media. Coubertin was himself convinced that knowledgeable spectators are essential to obtaining high levels of performance, while regretting that stadiums had (already) become too big (Coubertin 2000: 184 and 199).
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The longwave emission of planetary atmospheres that contain a condensable absorbing gas in the infrared (i.e., longwave), which is in equilibrium with its liquid phase at the surface, may exhibit an upper bound. Here we analyze the effect of the atmospheric absorption of sunlight on this radiation limit. We assume that the atmospheric absorption of infrared radiation is independent of wavelength except within the spectral width of the atmospheric window, where it is zero. The temperature profile in radiative equilibrium is obtained analytically as a function of the longwave optical thickness. For illustrative purposes, numerical values for the infrared atmospheric absorption (i.e., greenhouse effect) and the liquid vapor equilibrium curve of the condensable absorbing gas refer to water. Values for the atmospheric absorption of sunlight (i.e., antigreenhouse effect) take a wide range since our aim is to provide a qualitative view of their effects. We find that atmospheres with a transparent region in the infrared spectrum do not present an absolute upper bound on the infrared emission. This result may be also found in atmospheres opaque at all infrared wavelengths if the fraction of absorbed sunlight in the atmosphere increases with the longwave opacity
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Earth System Models (ESM) have been successfuly developed over past few years, and are currently beeing used for simulating present day-climate, seasonal to interanual predictions of climate change. The supercomputer performance plays an important role in climate modeling since one of the challenging issues for climate modellers is to efficiently and accurately couple earth System components on present day computers architectures. At the Barcelona Supercomputing Center (BSC), we work with the EC- Earth System Model. The EC- Earth is an ESM, which currently consists of an atmosphere (IFS) and an ocean (NEMO) model that communicate with each other through the OASIS coupler. Additional modules (e.g. for chemistry and vegetation ) are under development. The EC-Earth ESM has been ported successfully over diferent high performance computin platforms (e.g, IBM P6 AIX, CRAY XT-5, Intelbased Linux Clusters, SGI Altix) at diferent sites in Europ (e.g., KNMI, ICHEC, ECMWF). The objective of the first phase of the project was to identify and document the issues related with the portability and performance of EC-Earth on the MareNostrum supercomputer, a System based on IBM PowerPC 970MP processors and run under a Linux Suse Distribution. EC-Earth was successfully ported to MareNostrum, and a compilation incompatibilty was solved by a two step compilation approach using XLF version 10.1 and 12.1 compilers. In addition, the EC-Earth performance was analyzed with respect to escalability and trace analysis with the Paravear software. This analysis showed that EC-Earth with a larger number of IFS CPUs (<128) is not feasible at the moment since some issues exists with the IFS-NEMO balance and MPI Communications.
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Concrete curing is closely related to cement hydration, microstructure development, and concrete performance. Application of a liquid membrane-forming curing compound is among the most widely used curing methods for concrete pavements and bridge decks. Curing compounds are economical, easy to apply, and maintenance free. However, limited research has been done to investigate the effectiveness of different curing compounds and their application technologies. No reliable standard testing method is available to evaluate the effectiveness of curing, especially of the field concrete curing. The present research investigates the effects of curing compound materials and application technologies on concrete properties, especially on the properties of surface concrete. This report presents a literature review of curing technology, with an emphasis on curing compounds, and the experimental results from the first part of this research—lab investigation. In the lab investigation, three curing compounds were selected and applied to mortar specimens at three different times after casting. Two application methods, single- and double-layer applications, were employed. Moisture content, conductivity, sorptivity, and degree of hydration were measured at different depths of the specimens. Flexural and compressive strength of the specimens were also tested. Statistical analysis was conducted to examine the relationships between these material properties. The research results indicate that application of a curing compound significantly increased moisture content and degree of cement hydration and reduced sorptivity of the near-surface-area concrete. For given concrete materials and mix proportions, optimal application time of curing compounds depended primarily upon the weather condition. If a sufficient amount of a high-efficiency-index curing compound was uniformly applied, no double-layer application was necessary. Among all test methods applied, the sorptivity test is the most sensitive one to provide good indication for the subtle changes in microstructure of the near-surface-area concrete caused by different curing materials and application methods. Sorptivity measurement has a close relation with moisture content and degree of hydration. The research results have established a baseline for and provided insight into the further development of testing procedures for evaluation of curing compounds in field. Recommendations are provided for further field study.
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The purpose of the study is: (1) to describe how nursing students' experienced their clinical learning environment and the supervision given by staff nurses working in hospital settings; and (2) to develop and test an evaluation scale of Clinical Learning Environment and Supervision (CLES). The study has been carried out in different phases. The pilot study (n=163) explored the association between the characteristics of a ward and its evaluation as a learning environment by students. The second version of research instrument (which was developed by the results of this pilot study) were tested by an expert panel (n=9 nurse teachers) and test-retest group formed by student nurses (n=38). After this evaluative phase, the CLES was formed as the basic research instrument for this study and it was tested with the Finnish main sample (n=416). In this phase, a concurrent validity instrument (Dunn & Burnett 1995) was used to confirm the validation process of CLES. The international comparative study was made by comparing the Finnish main sample with a British sample (n=142). The international comparative study was necessary for two reasons. In the instrument developing process, there is a need to test the new instrument in some other nursing culture. Other reason for comparative international study is the reflecting the impact of open employment markets in the European Union (EU) on the need to evaluate and to integrate EU health care educational systems. The results showed that the individualised supervision system is the most used supervision model and the supervisory relationship with personal mentor is the most meaningful single element of supervision evaluated by nursing students. The ward atmosphere and the management style of ward manager are the most important environmental factors of the clinical ward. The study integrates two theoretical elements - learning environment and supervision - in developing a preliminary theoretical model. The comparative international study showed that, Finnish students were more satisfied and evaluated their clinical placements and supervision with higher scores than students in the United Kingdom (UK). The difference between groups was statistical highly significant (p= 0.000). In the UK, clinical placements were longer but students met their nurse teachers less frequently than students in Finland. Arrangements for supervision were similar. This research process has produced the evaluation scale (CLES), which can be used in research and quality assessments of clinical learning environment and supervision in Finland and in the UK. CLES consists of 27 items and it is sub-divided into five sub-dimensions. Cronbach's alpha coefficient varied from high 0.94 to marginal 0.73. CLES is a compact evaluation scale and user-friendliness makes it suitable for continuing evaluation.
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In Finland, European Union membership and economic globalisation have changed the position of regions from closed territorial systems to nodes of open international networks. The increasing complexity of cities as globalised knowledge centres and functionally specialised and diversified rural areas, and on the other hand growing disparities between prosperous urban cores and lagging peripheral areas are also essential features in contemporary regional development. These trends have produced new needs to promote mutual dialogue between cities and the countryside in western market economies. Urban-rural interaction is an idea which was developed in the late 1990s within regional policy to pull together these new challenges to regional development and handle cities and the countryside as a whole. The aim of my study is to conceptualise the idea of urban-rural interaction, explain the phenomenon theoretically, clarify past and present urban and rural development and analyse regional policies from the interaction angle. The ultimate purpose is to illustrate the existence and nature of particular interaction policy in a globalising society. The general method is discourse analysis, which I use in three cases: Central Finland, South-Ostrobothnia and South-West Finland. Theoretically I have a two-dimensional approach. On the first hand I use World-System theory to explain how the global economy is moulding urban and rural structures at the regional level. On the other hand I use regime theory to explain local political actions and practises between cities and the countryside under the overlapping pressures deriving from reformulated regional structures and policies.
Adaptation to globalisation in Finland has been carried out by strengthening urban centres. The stress in regional policy has been in urban development. The development of the countryside has mostly been implemented by a separate rural policy. At the end of the 1990s and early 2000s Finnish cities have actually shown themselves to be competitive in global markets. The drawbacks of the new growth centre policy have been the sparse network of prosperous cities and their weak spreading effects, which have hindered comprehensive regional development. Tensions between urban and rural areas have also deepened. In this situation the interaction policy is used as a way of balancing development and moderate conflicts within the regions. From this point of view urban-rural interaction can be seen as a way of tackling the challenges of globalisation.
On the other hand the results emphasise that actors involved in regional development still believe, although the hegemonic discourse is on urban policy, that there are opportunities to stimulate progress in the countryside as well. In the situation where regional authorities control development resources, rural development can be successful only if rural actors manage to establish fruitful relationships with their urban partners. This is also the weakness of the programme-based regional policy. If rural municipalities or other actors are for any reason incapable of building development regimes with cities, the offers of interaction policy will be useless.
The problem of the interaction policy is that the focus and methods of it have so far been rather underdeveloped. In order to improve the efficiency of the interaction policy, further research should concentrate on the social processes which define the position of cities and the countryside as partners of interaction, and practises which promote or prohibit the possibilities of developing the interaction policy. The efforts to define different contents of urban-rural interaction or promote interaction projects should not have such an important role in the future as they have had so far. Instead, the focus of interaction policy should be on questions such as how to manage the political tensions between town and country and how to create a positive atmosphere for regional policy where the needs of urban and rural development are promoted equally.
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iLEAPS (Integrated Land Ecosystem-Atmosphere Processes Study) on kansainvälinen tutkimusohjelma, jonka tavoitteena on parantaa maa-ilmakehä rajapinnan tuntemusta. Opinnäytetyönä on tehty iLEAPS:ille "jäsenrekisteri"-sovellus, jota on myöhemmin muokattu parantamalla muunmuassa käyttöliittymää. Lisäksi ohjelman eri palaset koottiin yhteen moduuleiksi, jonne on kerätty yhteen kuuluvia asioita kuten funktiot ja uuteen versioon tehdyt luokat. Sovellus on toteutettu PHP/MySQL-työkaluilla. Ohjelma koostuu kahdesta osasta: julkisilta www-sivuilta löytyvästä lomakkeesta sekä varsinaisesta tietokannan hallintatyökalusta. Lomakkeella pystyy ilmoittamaan itsensä halukkaaksi liittymään mukaan postituslistalle ja antamaan iLEAPS:ille tarvittavat tiedot itsestään. Hallintatyökalulla voidaan lisätä, poistaa ja muokata henkilöiden tietoja. Työkalun avulla voidaan myös lähettää halutuille ihmisille sähköpostia sekä tulostaa tarvittavia tietoja.
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Accurate estimates of water losses by evaporation from shallow water tables are important for hydrological, agricultural, and climatic purposes. An experiment was conducted in a weighing lysimeter to characterize the diurnal dynamics of evaporation under natural conditions. Sampling revealed a completely dry surface sand layer after 5 days of evaporation. Its thickness was <1 cm early in the morning, increasing to reach 4?5 cm in the evening. This evidence points out fundamental limitations of the approaches that assume hydraulic connectivity from the water table up to the surface, as well as those that suppose monotonic drying when unsteady conditions prevail. The computed vapor phase diffusion rates from the apparent drying front based on Fick's law failed to reproduce the measured cumulative evaporation during the sampling day. We propose that two processes rule natural evaporation resulting from daily fluctuations of climatic variables: (i) evaporation of water, stored during nighttime due to redistribution and vapor condensation, directly into the atmosphere from the soil surface during the early morning hours, that could be simulated using a mass transfer approach and (ii) subsurface evaporation limited by Fickian diffusion, afterward. For the conditions prevailing during the sampling day, the amount of water stored at the vicinity of the soil surface was 0.3 mm and was depleted before 11:00. Combining evaporation from the surface before 11:00 and subsurface evaporation limited by Fickian diffusion after that time, the agreement between the estimated and measured cumulative evaporation was significantly improved.
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As decisões de preços de venda, é uma das funções com mais relevância no ambiente empresarial para os gerentes, devido o seu carácter estratégico para o sucesso das empresas. O processo de formação de preço (FP) é fundamental para as empresas, embora apresenta graus de dificuldade e de complexidade, por implicar diversos factores. A primeira etapa para a FP consiste na estimativa correcta de custos, para obtenção de preços ideais. Para além dos custos, outros factores internos e externos devem ser analisados para que as decisões possam ser tomadas de forma correcta e obter um preço competitivo. Portanto, os gerentes precisam de informações precisas para poderem tomar decisões com segurança, levando em consideração todos os aspectos relevantes para a FP. O presente trabalho tem como objectivo principal, conhecer uma politica adequada de FP, bem como, descobrir quais os factores mais relevantes considerados na formação desses preços nas empresas e ainda conhecer quais os métodos de FP utilizado pelas empresas de importação de S.Vicente para a FP. A metodologia, consistiu primeiramente numa pesquisa bibliográfica e exploratória. Para a recolha dos dados,foram aplicados questionários com perguntas fechadas múltipla escolha, aos gerentes e aos responsáveis pelos processos de EC e FP e para complementar, foi feita uma entrevista a um especialista da área. Para a análise dos dados, foram utilizadas técnicas qualitativas e quantitativas, feito através das respostas obtidas dos questionários. Os resultados obtidos da pesquisa, mostram que o método de formação de preços de venda adoptado pelas empresas de S.Vicente, é o método baseado no custo e no mercado (método misto), ou seja, o preço é definido com base nos seus custos, mas é ajustado tendo por base o preço da concorrência. The sale prices decisions; it is one of the functions with more relevance in the managerial atmosphere for the managers, due your strategic character for the success of the companies. The process of price formation (FP) it is fundamental for the companies,although it presents degrees of difficulty and of complexity, for implicating several factors. The first stage for FP consists in estimate correct costs, to obtaining ideal prices. Besides the costs, others internal and external factors should be analyzed so that decisions can be made in a correct form to obtain a competitive price. Therefore, the managers need necessary information to make safety decisions, taking in consideration all the important aspects of FP. The main objective of this present work, is to know the appropriate politics of FP, as well as, to discover which the most important factors considered in the formation of those prices to purchases and still to know which of the FP methods used by the import companies in São Vicente. The methodology consisted firstly in a bibliographical and exploratory research. To collect the data, were applied uestionnaires with closed questions, multiple choice to the managers and the responsible for the processes of ECP and EP and to complement, it was made an interview to a specialist. For the analysis of the data, qualitative techniques were used, done through to obtained answers of the questionnaires. The results of the research, show that the method of formation of sale prices adopted for São Vicente's companies, is the method based on the cost and in the market (mixed method), in other words, the price is defined with base in the costs, but it is adjusted tends for base of the competition.
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A dinâmica de desenvolvimento de Cabo Verde vem sendo uma constante, com ganhos significativos para o país, como atestam a recente adesão à Organização Mundial do Comércio, a graduação a País de Rendimento Médio e a Parceria Especial com a União Europeia. No dia 23 de Julho de 2008, Cabo Verde tornou-se no 153º Estado membro da Organização Mundial do Comércio, sendo que nesta conquista foi o primeiro país Africano e o terceiro País Menos Avançado a conseguir este importante marco via negocial. As vantagens advenientes desta adesão são muitas, sendo de destacar a maior confiança dos investidores no país ao propiciar-se a expansão do mercado e a realização de negócios num ambiente mais seguro e estável, e ainda a possibilidade de melhoria da qualidade de prestação de serviços, uma vez que tudo passou a ser norteado por padrões e regras do comércio internacional. Este trabalho foi elaborado com base em pesquisa bibliográfica e exploratória necessária à construção de um referencial teórico sobre o assunto em questão, tendo como base artigos, livros, revistas e consultas em websites. Finalizando, para avaliação, apresentamos uma componente prática com base num questionário aplicado ao tecido empresarial, com perguntas abertas e de múltipla escolha, onde os inquiridos puderam fazer a sua apreciação relativa ao processo de adesão, e às expectativas advenientes. Os resultados obtidos no final do trabalho mostraram de forma clara e inequívoca a necessidade de Cabo Verde se reorganizar, reforçar o sector privado e a competitividade das empresas, através de, designadamente: melhoria do ambiente fiscal das empresas, fomento e apoio às pequenas e médias empresas. Outrossim, há que dar seguimento as reformas no sector comercial, capacitando e formando quadros nacionais uma vez que estes desempenham um papel essencial no crescimento económico do país e permitem dar maior previsibilidade aos investidores, sendo este último um dos pilares decisivos no requisito do investimento externo. The dynamics of the development of Cape Verde is becoming a constant, with significant gains to the country, as attests the recent adhesion to the World Trade Organization, the graduation to Country of Medium Revenue, as well as the Special Partnership with the European Union. On July 23, 2008, Cape Verde became the 153rd State member of the World Trade Organization, and in this conquest it was the first African country and the third Less Advanced Country to get this mark through negotiable way. The advantages proceeding from this adhesion are many, highlighting the investors' largest trust in the country when propitiating the expansion of the market and the accomplishment of business in a safer and stable atmosphere, and still the possibility of improvement of the quality of installment of services, once everything started being guided by patterns and rules of the international trade. This work was elaborated based on bibliographical and exploratory researches necessary to the construction of the theoretical referential about the subject in question, based on articles, books, magazines and website researches. Concluding, for evaluation, we presented a practical component based on a questionnaire applied to the managerial stuff, with open and multiple choice questions, where the inquired could make his appreciation related to the adhesion process, and the proceeding expectations. The results obtained at the end of the work, showed in a clear way the need of Cape Verde to organize, to reinforce the private sector and the competitiveness of the companies, through, namely: the improvement of the fiscal atmosphere of the companies, fomentation and support of the small and medium companies. Meanwhile, it is important to continue the reforms in the commercial sector, qualifying and forming national staff once they play an essential part in the economic growth of the country and allow giving a larger previsibility to the investors, being this last one, one of the decisive pillars in the requirement of the external investment.
Resumo:
BACKGROUND:: Mechanical stretch has been shown to induce vascular remodeling and increase vessel density, but the pathophysiologic mechanisms and the morphologic changes induced by tensile forces to dermal vessels are poorly understood. METHODS:: A custom computer-controlled stretch device was designed and applied to the backs of C57BL/6 mice (n = 38). Dermal and vascular remodeling was studied over a 7-day period. Corrosion casting and three-dimensional scanning electron microscopy and CD31 staining were performed to analyze microvessel morphology. Hypoxia was assessed by immunohistochemistry. Western blot analysis of vascular endothelial growth factor (VEGF) and mRNA expression of VEGF receptors was performed. RESULTS:: Skin stretching was associated with increased angiogenesis as demonstrated by CD31 staining and vessel corrosion casting where intervascular distance and vessel diameter were decreased (p < 0.01). Immediately after stretching, VEGF dimers were increased. Messenger RNA expression of VEGF receptor 1, VEGF receptor 2, neuropilin 1, and neuropilin 2 was increased starting as early as 2 hours after stretching. Highly proliferating epidermal cells induced epidermal hypoxia starting at day 3 (p < 0.01). CONCLUSIONS:: Identification of significant hypoxic cells occurred after identification of neovessels, suggesting an alternative mechanism. Increased expression of angiogenic receptors and stabilization of VEGF dimers may be involved in a mechanotransductive, prehypoxic induction of neovascularization.