23 research outputs found

    Broadband feed for a parabolic antenna for satellite tracking.

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    Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 201

    Estudo da implementação da filosofia Lean na indústria Portuguesa

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    A forte competitividade dos mercados a nível nacional e internacional tem levado muitas empresas a estudar métodos e técnicas de incremento à eliminação dos desperdícios, à redução de custos e tempos, ao aumento da qualidade e da flexibilidade, tendo a filosofia lean um papel crucial na prossecução destes objectivos. Desde os seus primórdios, a avaliação da implementação da filosofia lean no universo das empresas é uma questão de investigação na área de conhecimento da gestão industrial. Embora a nível individual as diferentes empresas possam quantificar e avaliar os resultados da aplicação do lean, a grande dificuldade surge quando se pretende obter uma comparação por sector ou tipo de actividade económica. Existem países onde a prática do lean tem sido prioritária e as empresas ocupam a vanguarda nesta área de conhecimento. No entanto, em Portugal, existe uma clara dificuldade em se determinar até que ponto o tecido empresarial português assimilou esta filosofia e que resultados têm obtido com a prática do lean. Este trabalho apresenta um estudo realizado a partir de um inquérito, obtido através de um questionário on-line, às empresas que operam em Portugal de forma a estudar e analisar o estado actual do lean em Portugal e antever tendências futuras numa perspectiva de evolução da aplicação desta metodologia de gestão de processos produtivos. Em resultado deste estudo foi possível identificar quais são os grandes obstáculos à introdução do lean, áreas em que se observou sucesso ou menor impacto e quais as ferramentas e técnicas mais usadas por sector. Como resultado deste estudo é convicção do autor que foi possível obter uma fotografia abrangente do actual estado de implementação do lean e desta forma caracterizar as áreas que seguem na vanguarda da implementação do lean, e as áreas que ainda apresentam um desenvolvimento incipiente. Desta forma parece ao autor que o presente estudo apresenta grande utilidade para o mundo académico bem como para o tecido empresarial português.The strong competitive national and international markets led to many companies exploring methods and techniques for increasing the elimination of waste, reducing costs and lead times, and increasing quality and flexibility with lean philosophy playing a pivotal role in these objectives. Since its inception evaluating the implementation of lean philosophy in the universe of companies is a matter of research in the knowledge management industry. While the different companies can individually quantify and evaluate the results of the application of lean a comparison by sector or type of business is much more difficult. In some countries the practice of lean has been a priority and companies occupy the forefront of knowledge in this area. In Portugal, however, it is clearly difficult to determine to what extent the Portuguese business assimilated this philosophy and the results obtained with the practice Lean. In this study, the author presents analysis of a survey, obtained through an online questionnaire, of companies operating in Portugal to analyze and determine the current state of lean in Portugal and anticipate future trends on an evolutionary basis of the application of this methodology of processes management. As a result of this study it was possible to identify the major obstacles to the introduction of lean, areas in which there is less success or impact and which tools and techniques are used in each industry. As a result of this study it is the author's conviction that it was possible to obtain a comprehensive picture of the current state of implementation of lean and thus characterize areas at the forefront in the implementation of lean, and areas still showing an incipient development. Therefore, it seems to the author that this study is very useful for the academic world as well as the Portuguese business

    ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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    Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

    Reproductive responses and productive characteristics in ewes supplemented with detoxified castor meal for a long period

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    The objective of the present study was to evaluate the effects of supplementation with detoxified castor meal (DCM) in the diet of ewes during pregnancy, partum, and post-partum on the weight development of their offspring and at slaughter. The study included 56 ewes with synchronized estrus that were naturally mated. At the beginning of pregnancy and in post-partum, hepatic and renal function-related parameters and progesterone levels were measured. At slaughter, the proximate composition and fatty acid profile were determined in the loin of ewes. There was no effect of diet on reproductive response after estrus synchronization. At the beginning of pregnancy, albumin and creatinine levels were lower in the DCM group. Supplementation with DCM did not alter the weight or body condition of ewes at partum. However, at weaning, the DCM group showed a higher loin-eye area (LEA) in relation to the group fed diets without detoxified castor meal (WDCM). At partum, as well as at weaning, the offspring of the ewes supplemented with DCM had a larger LEA than the WDCM group. In post-partum, levels of glucose, urea, protein, and cholesterol were lower in the DCM group. The return to cyclicity was similar in both groups, with an average of 47 days after partum. At slaughter, neither anatomical and carcass components nor the results of the proximate analysis were affected by the type of diet, except for an increase in heptadecanoic acid in the DCM group. Supplementation with detoxified castor meal in the diet of ewes does not affect lambing, pregnancy, prolificacy, return to cyclicity, milk production, blood biochemical parameters, or carcass characteristics

    Incidence of aplastic anemia and agranulocytosis in Latin America: the LATIN study

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    CONTEXT AND OBJECTIVE: Aplastic anemia and agranulocytosis are rare but life-threatening disorders, often caused by drugs and other environmental exposures. Reported incidence of these diseases seems to vary between different geographic regions, and few data on their incidence are available for Latin American countries. The aim of this work is to determine the incidence of agranulocytosis and aplastic anemia in Brazil. DESIGN AND SETTING: Incidence study. Seven centers took part in the pilot phase, so as to represent all Brazilian regions. METHODS: Each center conducted an active search for new cases in a defined region by means of regular contacts with all hematologists, main clinical laboratories and clinicians in hospitals of the region. RESULTS: 74 patients with aplastic anemia and 16 with agranulocytosis were identified. Patients with agranulocytosis had a median age of 31 years (interquartile range, IQR: 12.5-48.2); 32.2% were male and 81.2% were white. The median age of aplastic anemia patients was 21 years (IQR 15.0-35.2); 62.2% were male, 50.0% were white and 39.2% mulatto. The incidence of agranulocytosis was estimated to be 0.5 cases per million individuals per year, ranging from 0.0 to 1.1 cases per million per year between regions. The incidence of aplastic anemia was 2.7 cases per million per year, ranging from 1.1 to 7.1 cases per million per year between regions. CONCLUSIONS: Aplastic anemia and agranulocytosis are rare diseases in Brazil. However, there is considerable variability in their incidences between different regions

    Macrobrachium amazonicum: an alternative for microbiological monitoring of aquatic environments in Brazil

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    This study aimed to evaluate the role of the Amazon River prawn, Macrobrachium amazonicum, as carrier of Candida spp., by analyzing the correlation between Candida spp. from these prawns and their environment (surface water and sediment), through M13-PCR fingerprinting and RAPD-PCR. For this purpose, 27 strains of Candida spp. were evaluated. These strains were recovered from the gastrointestinal tract of adult M. amazonicum (7/27) from Catú Lake, Ceará State, Brazil and from the aquatic environment (surface water and sediment) of this lake (20/27). Molecular comparison between the strains from prawns and the aquatic environment was conducted by M13-PCR fingerprinting and RAPD-PCR, utilizing the primers M13 and OPQ16, respectively. The molecular analysis revealed similarities between the band patterns of eight Candida isolates with the primer M13 and 11 isolates with the primer OPQ16, indicating that the same strains are present in the digestive tract of M. amazonicum and in the aquatic environment where these prawns inhabit. Therefore, these prawns can be used as sentinels for environmental monitoring through the recovery of Candida spp. from the aquatic environment in their gastrointestinal trac

    Evaluation of three recombinant proteins for the development of ELISA and immunochromatographic tests for visceral leishmaniasis serodiagnosis

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    BACKGROUND Visceral Leishmaniasis (VL) is an infectious disease that is a significant cause of death among infants aged under 1 year and the elderly in Brazil. Serodiagnosis is a mainstay of VL elimination programs; however, it has significant limitations due to low accuracy. OBJECTIVE This study aimed to evaluate three recombinant Leishmania infantum proteins (rFc, rC9, and rA2) selected from previous proteomics and genomics analyses to develop enzyme-linked immunosorbent assay (ELISA) and immunochromatographic tests (ICT) for the serodiagnosis of human VL (HVL) and canine VL (CVL). METHODS A total of 186 human (70 L. infantum-infected symptomatic, 20 other disease-infected, and 96 healthy) and 185 canine (82 L. infantum-infected symptomatic, 27 L. infantum-infected asymptomatic, and 76 healthy) sera samples were used for antibody detection. FINDINGS Of the three proteins, rA2 (91.5% sensitivity and 87% specificity) and rC9 (95.7% sensitivity and 87.5% specificity) displayed the best performance in ELISA-HVL and ELISA-CVL, respectively. ICT-rA2 also displayed the best performance for HVL diagnosis (92.3% sensitivity and 88.0% specificity) and had high concordance with immunofluorescence antibody tests (IFAT), ELISA-rK39, IT-LEISH®, and ELISAEXT. ICT-rFc, ICT-rC9, and ICT-rA2 had sensitivities of 88.6%, 86.5%, and 87.0%, respectively, with specificity values of 84.0%, 92.0%, and 100%, respectively for CVL diagnosis. MAIN CONCLUSIONS The three antigens selected by us are promising candidates for VL diagnosis regardless of the test format, although the antigen combinations and test parameters may warrant further optimisation
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