997 resultados para historical source


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Leprosy is an ancient infectious disease caused by Mycobacterium leprae. According to comparative genomics studies, this disease originated in Eastern Africa or the Near East and spread with successive human migrations. The Europeans and North Africans introduced leprosy into West Africa and the Americas within the past 500 years. In Brazil, this disease arrived with the colonizers who disembarked at the first colonies, Rio de Janeiro, Salvador and Recife, at the end of the sixteenth century, after which it was spread to the other states. In 1854, the first leprosy cases were identified in State of Amazonas in the north of Brazil. The increasing number of leprosy cases and the need for treatment and disease control led to the creation of places to isolate patients, known as leprosaria. One of them, Colonia Antônio Aleixo was built in Amazonas in 1956 according to the most advanced recommendations for isolation at that time and was deactivated in 1979. The history of the Alfredo da Matta Center (AMC), which was the first leprosy dispensary created in 1955, parallels the history of leprosy in the state. Over the years, the AMC has become one of the best training centers for leprosy, general dermatology and sexually transmitted diseases in Brazil. In addition to being responsible for leprosy control programs in the state, the AMC has carried out training programs on leprosy diagnosis and treatment for health professionals in Manaus and other municipalities of the state, aiming to increase the coverage of leprosy control activities. This paper provides a historical overview of leprosy in State of Amazonas, which is an endemic state in Brazil.

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Based on samples cross-sections from the Main Altarpiece of the Coimbra Old Cathedral, where a blue coating performed in 1685 is observed (that was partly covered with a Prussian blue-containing overpaint), the raw materials present in this coating were reproduced and studied. Blue areas were painted with smalt in oil, according to the contract signed by Manoel da Costa Pereira in 1684 and the analysis by Le Gac in 2009. Based on these, three batches of cobalt-based glasses (S1, S2 and S3) were heated and melted in alumina crucibles in the kiln. S1 contained 6.03 % of cobalt oxide, S2 contained 2.10 %, with the addition of 1.49 % of magnesium oxide, and S3 contained 6.82 % of cobalt oxide, with the addition of 4.63% of antimony trioxide. These batches were ground mechanically with water and manually with different vehicles stated in recipes. The results were studied by means of OM, SEM-EDS, X-Ray CT, Colorimetry and Vickers HT. Different binders were also produced and analyzed by means of μ-FTIR, in order to perform their characterization and obtain Standard Spectra. Since anhydrite was identified in the ground layers, gypsum from Óbidos was also characterized by XRD. The main goal of this thesis was to study all the raw materials present in the 1685-blue coating, in order to allow the historically accurate reconstruction of the layers build-up in the next future.

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The restoration materials currently used to fill gaps in architectural historical azulejos (e.g. lime or organic resin pastes) usually show serious drawbacks in terms of compatibility, effectiveness and durability. The existing solutions do not fully protect azulejos in outdoor conditions and frequently result in further deterioration. Geopolymers can be a potential solution for azulejo lacunae infill given the chemical-mineralogical similitude to the ceramic body, and also the durability and versatile range of physical properties that can be obtained through the manipulation of their formulation and curing conditions. This work presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in azulejos or to act as “cold” cast ceramic tile surrogates reproducing missing azulejo fragments. The formulation of geopolymers, namely the type of activators, the aluminosilicate source, the amount of water (to meet adequate workability requirements) and curing conditions were studied. The need for post-curing desalination was also considered envisaging their application in the restoration of outdoor architectural historical azulejos frequently exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of azulejos are also discussed. Several techniques were used to study the chemical and physical behavior of geopolymers, namely FT-IR, XRD, MIP, SEM-EDS, WDXRF, electrical conductivity, open porosity, bending strength, adhesion strength, water vapour permeability, thermal expansion and hydric expansion. The results indicate that geopolymers are a promising material for restoration of azulejos, exhibiting some properties, such as adhesion to the ceramic substrate, higher than inorganic materials used nowadays, such as aerial lime based pastes.

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Contém resumo

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In this paper, we analyze the behavior of real interest rates over the long-run using historical data for nine developed economies, to assess the extent to which the recent decline observed in most advanced countries is at odds with the past data, as suggested by the Secular Stagnation hypothesis. By using data from 1703 and performing stationarity and structural breaks tests, we find that the recent decline in interest rates is not explained by a structural break in the time series. Our results also show that considering long-run data leads to different conclusions than using short-run data.

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This article deals with the splendid panoramic painting depicting the Joyeuse Entrée of King Philipp III (Filipe II de Portugal) in Lisbon in 1619 which the author discovered at Weilburg castle in Germany. The author places the painting in its historical and pictorial context by comparing it to the written reports of the entry and comparable 16th and 17th century views of Lisbon. Apparently, the painting is based on a strictly planned choreography that largely follows the previous entry of Philipp II, and is identical in the painted, engraved and written descriptions of the event published between 1619 and 1622.

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RESUMO - As organizações de saúde, em geral, e os hospitais, em particular, são frequentemente reconhecidos por terem particularidades e especificidades que conferem uma especial complexidade ao seu processo produtivo e à sua gestão (Jacobs, 1974; Butler, 1995). Neste sentido, na literatura hospitalar emergem alguns temas como prioritários tanto na investigação como na avaliação do seu funcionamento, nomeadamente os relacionados com a produção, com o financiamento, com a qualidade, com a eficiência e com a avaliação do seu desempenho. O estado da arte da avaliação do desempenho das organizações de saúde parece seguir a trilogia definida por Donabedian (1985) — Estrutura, Processo e Resultados. Existem diversas perspectivas para a avaliação do desempenho na óptica dos Resultados — efectividade, eficiência ou desempenho financeiro. No entanto, qualquer que seja a utilizada, o ajustamento pelo risco é necessário para se avaliar a actividade das organizações de saúde, como forma de medir as características dos doentes que podem influenciar os resultados de saúde. Como possíveis indicadores de resultados, existem a mortalidade (resultados finais), as complicações e as readmissões (resultados intermédios). Com excepção dos estudos realizados por Thomas (1996) e Thomas e Hofer (1998 e 1999), praticamente ninguém contesta a relação entre estes indicadores e a efectividade dos cuidados. Chamando, no entanto, a atenção para a necessidade de se definirem modelos de ajustamento pelo risco e ainda para algumas dificuldades conceptuais e operacionais para se atingir este objectivo. Em relação à eficiência técnica dos hospitais, os indicadores tradicionalmente mais utilizados para a sua avaliação são os custos médios e a demora média. Também neste domínio, a grande maioria dos estudos aponta para que a gravidade aumenta o poder justificativo do consumo de recursos e que o ajustamento pelo risco é útil para avaliar a eficiência dos hospitais. Em relação aos sistemas usados para medir a severidade e, consequentemente, ajustar pelo risco, o seu desenvolvimento apresenta, na generalidade, dois tipos de preocupações: a definição dos suportes de recolha da informação e a definição dos momentos de medição. Em última instância, o dilema que se coloca reside na definição de prioridades e daquilo que se pretende sacrificar. Quando se entende que os aspectos financeiros são determinantes, então será natural que se privilegie o recurso quase exclusivo a elementos dos resumos de alta como suporte de recolha da informação. Quando se defende que a validade de construção e de conteúdo é um aspecto a preservar, então o recurso aos elementos dos processos clínicos é inevitável. A definição dos momentos de medição dos dados tem repercussões em dois níveis de análise: na neutralidade económica do sistema e na prospectividade do sistema. O impacto destas questões na avaliação da efectividade e da eficiência dos hospitais não é uma questão pacífica, visto que existem autores que defendem a utilização de modelos baseados nos resumos de alta, enquanto outros defendem a supremacia dos modelos baseados nos dados dos processos clínicos, para finalmente outros argumentarem que a utilização de uns ou outros é indiferente, pelo que o processo de escolha deve obedecer a critérios mais pragmáticos, como a sua exequibilidade e os respectivos custos de implementação e de exploração. Em relação às possibilidades que neste momento se colocam em Portugal para a utilização e aplicação de sistemas de ajustamento pelo risco, verifica-se que é praticamente impossível a curto prazo aplicar modelos com base em dados clínicos. Esta opção não deve impedir que a médio prazo se altere o sistema de informação dos hospitais, de forma a considerar a eventualidade de se utilizarem estes modelos. Existem diversos problemas quando se pretendem aplicar sistemas de ajustamento de risco a populações diferentes ou a subgrupos distintos das populações donde o sistema foi originalmente construído, existindo a necessidade de verificar o ajustamento do modelo à população em questão, em função da sua calibração e discriminação.

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From four solutions tested to extract tannins from mangrove bark for wood adhesives, hot water is recommended. Hot water extracted 21.4% of formaldehyde-hydrochloric acid reactive polyphenols on oven-dry bark basis.

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This paper presents a comprehensive comparison of a current-source converter and a voltage-source converter for three-phase electric vehicle (EV) fast battery chargers. Taking into account that the current-source converter (CSC) is a natural buck-type converter, the output voltage can assume a wide range of values, which varies between zero and the maximum instantaneous value of the power grid phase-to-phase voltage. On the other hand, taking into account that the voltage-source converter (VSC) is a natural boost-type converter, the output voltage is always greater than the maximum instantaneous value of the power grid phase-to-phase voltage, and consequently, it is necessary to use a dc-dc buck-type converter for applications as EV fast battery chargers. Along the paper is described in detail the principle of operation of both the CSC and the VSC for EV fast chargers, as well as the main equations of the power theory and current control strategies. The comparison between both converters is mainly established in terms of the total harmonic distortion of the grid current and the estimated efficiency for a range of operation between 10 kW and 50 kW.

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This paper presents a three-phase three-level fast battery charger for electric vehicles (EVs) based in a current-source converter (CSC). Compared with the traditional voltage-source converters used for fast battery chargers, the CSC can be seen as a natural buck-type converter, i.e., the output voltage can assume a wide range of values, which varies between zero and the maximum instantaneous value of the power grid phase-to-phase voltage. Moreover, using the CSC it is not necessary to use a dc-dc back-end converter in the battery side, and it is also possible to control the grid current in order to obtain a sinusoidal waveform, and in phase with the power grid voltage (unitary power factor). Along the paper is described in detail the proposed CSC for EVs fast battery charging systems: the circuit topology, the power control theory, the current control strategy and the grid synchronization algorithm. Several simulation results of the EV fast battery charger operating with a maximum power of 50 kW are presented.

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Solar photovoltaic systems are an increasing option for electricity production, since they produce electrical energy from a clean renewable energy resource, and over the years, as a result of the research, their efficiency has been increasing. For the interface between the dc photovoltaic solar array and the ac electrical grid is necessary the use of an inverter (dc-ac converter), which should be optimized to extract the maximum power from the photovoltaic solar array. In this paper is presented a solution based on a current-source inverter (CSI) using continuous control set model predictive control (CCS-MPC). All the power circuits and respective control systems are described in detail along the paper and were tested and validated performing computer simulations. The paper shows the simulation results and are drawn several conclusions.

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This paper presents the proposal of a three phase current source shunt active power filter (CS-SAPF) with photovoltaic grid interface. The proposed system combines the compensation of reactive power and harmonics with the injection of energy from a solar photovoltaic array into the electrical power grid. The proposed equipment presents the advantage of giving good use to the current source inverter, even when the solar photovoltaic array is not producing energy. The paper describes the control system of the CS SAPF, the energy injection control strategy, and the current harmonics and power factor compensation strategy. Simulation results to assess the performance of the proposed system are also presented.

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In the investigation and diagnosis of damages to historical masonry structures, the state of stress of the masonry is an important characteristic that must be determined with as much accuracy as possible. Flat-jack testing is a traditional method used to determine the state of stress in historical masonry structures. However, when irregular masonry is tested the method can cause damage to the masonry units and the accuracy of the method is reduced. An enhanced technique, called tube-jack testing, is being developed at the University of Minho to reduce the damage caused during testing and improve the accuracy when used on irregular masonry. This method uses multiple cylindrical jacks inserted in a line of holes drilled in the mortar joints of the masonry, avoiding damage to the masonry units. Concurrently with the development of tube-jack testing, the effect of stress state on sonic testing is being studied. Sonic testing is often used to determine locations of voids and damage in masonry. The focus of these studies was to determine if the state of stress is influencing the sonic test results. In this paper the results of tube-jack testing and sonic testing on masonry walls, built for the purpose of this study in the laboratory, loaded in compression is presented. The tube-jack testing is used to estimate the state of stress in the masonry and the sonic test results are evaluated based on the effect of the applied load on the wall. Future testing and study are suggested for continued development of these test methods.

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We are living in the era of Big Data. A time which is characterized by the continuous creation of vast amounts of data, originated from different sources, and with different formats. First, with the rise of the social networks and, more recently, with the advent of the Internet of Things (IoT), in which everyone and (eventually) everything is linked to the Internet, data with enormous potential for organizations is being continuously generated. In order to be more competitive, organizations want to access and explore all the richness that is present in those data. Indeed, Big Data is only as valuable as the insights organizations gather from it to make better decisions, which is the main goal of Business Intelligence. In this paper we describe an experiment in which data obtained from a NoSQL data source (database technology explicitly developed to deal with the specificities of Big Data) is used to feed a Business Intelligence solution.

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The filamentous fungus Ashbya gossypii has been safely and successfully used for more than two decades in the commercial production of riboflavin (vitamin B2). Its industrial relevance combined with its high genetic similarity with Saccharomyces cerevisiae together promoted the accumulation of fundamental knowledge that has been efficiently converted into a significant molecular and in silico toolbox for its genetic engineering. This synergy has enabled a directed and sustained exploitation of A. gossypii as an industrial riboflavin producer. Although there is still room for optimizing riboflavin production, the recent years have seen an abundant advance in the exploration of A. gossypii for other biotechnological applications, such as the production of recombinant proteins, single cell oil and flavour compounds. Here, we will address the biotechnological potential of A. gossypii beyond riboflavin production by presenting (a) a physiological and metabolic perspective over this fungus; (b) the molecular toolbox available for its manipulation; and (c) commercial and emerging biotechnological applications for this industrially important fungus, together with the approaches adopted for its engineering.