11 research outputs found

    pMOSFET fabrication using a low temperature pre-deposition technique

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    The objective of this work was to develop a fully functional pMOSFET using a new method for dopant pre-deposition done at low temperature (90ºC) using PECVD. This technique has many advantages when compared to the traditional manufacturing method, namely it is more cost effective, simpler and faster. Because it does not require an oxide layer to create the patterns, it can be conjugated with other low temperature techniques. To obtain a functional pMOSFET, this work was divided in four different studies. The objective of the first study was to achieve metal-semiconductor ohmic contacts. To obtain a perfect ohmic contact of aluminum in a n-type silicon wafer, it is necessary to create a narrow space-charge region in order to allow carrier tunneling. That was reached by using a highly doped n-type hydrogenated amorphous silicon thin film made with a phosphine gas phase concentration of 1.5%, followed by a one-hour diffusion process at 1000ºC. A sheet resistance of 22.9 Ω/□ and a phosphorus surface concentration of 5.2 × 1019 aṫ cm-3 were obtained. The second study consisted of producing p+n junctions varying the surface concentration and the diffusion time and temperature. The best diodes produced have significantly different profiles. The first was produced with a deep junction and a 0.165% diborane in the gas phase and presents the following parameters: rectification ratio of 6.01 × 103, threshold voltage of 0.53 V and an ideality factor of 1.74. The second diode was produced with a shallow junction and using a 1.5% diborane in the gas phase with the parameters: rectification ration of 3.94 × 103, a threshold voltage of 0.46 V and an ideality factor of 2.58. Regarding the oxide characteristics for application as gate dielectric (third study), it was determined that the best oxides were produced by wet oxidation with a thickness of about 1300 Å. After finishing the previous studies, it was possible to produce a fully functional p-type field effect transistor (fourth study). The MOSFETs worked in enhancement mode with the best parameters being: a threshold voltage of -4 V and a field effect mobility of 106.56 cm2/Vs

    Qualidade de Vida e Governação Urbana. Relatório Final

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    UID/SOC/04647/2013; Projecto Estudo Científico de Inquirição aos Munícipes e Principais Agentes da Cidade de Lisboa relativo à Qualidade de Vida e Governação UrbanaO presente trabalho de pesquisa, intitulado “Inquirição aos Munícipes e Principais Agentes da Cidade de Lisboa: Qualidade de Vida e Governação Urbana”, tem como principal objetivo analisar os impactos percecionados pelos munícipes e pelos principais agentes da cidade em resultado das mudanças introduzidas nos modelos de governação urbana e os seus efeitos na qualidade de vida em Lisboa. A pesquisa ancora-se empiricamente no quadro mais amplo das mudanças que a cidade de Lisboa vive atualmente: mudanças nas suas estruturas sociodemográficas, económicas e culturais, bem como nas perceções de urbanidade, de utilização e de usufrutos urbanos que lhe são associadas.publishersversionpublishe

    Quantification of platelets obtained by different centrifugation protocols in SHR rats

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    ABSTRACT OBJECTIVE: To quantify the platelet concentration in the blood of SHR rats, by means of different centrifugation protocols, and to evaluate what the most effective method for obtaining platelets is. METHODS: We used 40 male rats of the isogenic SHR lineage. The animals were divided into three groups: control, using whole blood without centrifugation; single centrifugation, using whole blood subjected to a single centrifugation at 200 × gand 400 × g; and double centrifugation, using whole blood subjected one centrifugation at different rotations, followed by collection of whole plasma subjected to another centrifugation at different rotations: 200 × g+ 200 ×g; 200 × g+ 400 × g; 200 × g+ 800 × g; 400 ×g+ 400 × g; 400 × g+ 800 × g. Samples of 3 ml of blood were drawn from each animal by means of cardiac puncture. The blood was stored in Vacutainer collection tubes containing 3.2% sodium citrate. The blood from the control group animals was analyzed without being subjected to centrifugation. After the blood from the other groups of animals had been subjected to centrifugation, the whole plasma was collected and subjected to platelet counting in the lower third of the sample. RESULTS: We obtained greatest platelet enrichment in the subgroup with two centrifugations comprising 400 × gfor 10 min + 400 ×gfor 10 min, in which the mean platelet concentration was 11.30 times higher than that of the control group. CONCLUSION: It was possible to obtain a high platelet concentration using viable simple techniques, by means of centrifugation of whole blood and use of commonly used materials. The most effective method for obtaining platelet concentrate was found in samples subjected to two centrifugations

    Usefulness of Routine Fractional Flow Reserve for Clinical Management of Coronary Artery Disease in Patients With Diabetes

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    International audienceThis cross-sectional study evaluates the association of major adverse cardiac events (MACE) integrated with fractional flow reserve as the management strategy for diabetes with outcomes in patients with ambiguous lesions who undergo angiography.Key PointsQuestionWhat are the usefulness, rate of major adverse cardiovascular events (MACE), and clinical outcomes of routinely integrating fractional flow reserve in the management strategy for patients with diabetes who undergo coronary angiography? FindingsIn this cross-sectional study of 1983 patients, overall reclassification by fractional flow rate was high and similar in patients with diabetes (41.2%) and patients without diabetes (37.5%); however, reclassification from medical treatment to revascularization was more frequent among patients with diabetes. The rate of 1-year MACE was similar in reclassified (9.7%) and nonreclassified (12.0%) patients with diabetes, and the rate of MACE of patients deferred based on fractional flow reserve was similar among those with and without diabetes. MeaningThe findings suggest that management strategies guided by fractional flow reserve, including revascularization deferral, may be useful for patients with diabetes.ImportanceApproximately one-third of patients considered for coronary revascularization have diabetes, which is a major determinant of clinical outcomes, often influencing the choice of the revascularization strategy. The usefulness of fractional flow reserve (FFR) to guide treatment in this population is understudied and has been questioned. ObjectiveTo evaluate the usefulness and rate of major adverse cardiovascular events (MACE) of integrating FFR in management decisions for patients with diabetes who undergo coronary angiography. Design, Setting, and ParticipantsThis cross-sectional study used data from the PRIME-FFR study derived from the merger of the POST-IT study (Portuguese Study on the Evaluation of FFR-Guided Treatment of Coronary Disease [March 2012-November 2013]) and R3F study (French Study of FFR Integrated Multicenter Registries Implementation of FFR in Routine Practice [October 2008-June 2010]), 2 prospective multicenter registries that shared a common design. A population of all-comers for whom angiography disclosed ambiguous lesions was analyzed for rates, patterns, and outcomes associated with management reclassification, including revascularization deferral, in patients with vs without diabetes. Data analysis was performed from June to August 2018. Main Outcomes and MeasuresDeath from any cause, myocardial infarction, or unplanned revascularization (MACE) at 1 year. ResultsAmong 1983 patients (1503 [77%] male; mean [SD] age, 65 [10] years), 701 had diabetes, and FFR was performed for 1.4 lesions per patient (58.2% of lesions in the left anterior descending artery; mean [SD] stenosis, 56% [11%]; mean [SD] FFR, 0.81 [0.01]). Reclassification by FFR was high and similar in patients with and without diabetes (41.2% vs 37.5%, P=.13), but reclassification from medical treatment to revascularization was more frequent in the former (142 of 342 [41.5%] vs 230 of 730 [31.5%], P=.001). There was no statistical difference between the 1-year rates of MACE in reclassified (9.7%) and nonreclassified patients (12.0%) (P=.37). Among patients with diabetes, FFR-based deferral identified patients with a lower risk of MACE at 12 months (25 of 296 [8.4%]) compared with those undergoing revascularization (47 of 257 [13.1%]) (P=.04), and the rate was of the same magnitude of the observed rate among deferred patients without diabetes (7.9%, P=.87). Status of insulin treatment had no association with outcomes. Patients (6.6% of the population) in whom FFR was disregarded had the highest MACE rates regardless of diabetes status. Conclusions and RelevanceRoutine integration of FFR for the management of coronary artery disease in patients with diabetes may be associated with a high rate of treatment reclassification. Management strategies guided by FFR, including revascularization deferral, may be useful for patients with diabetes

    Homens da cana e hospitais do açúcar: uma arquitetura da saúde no Estado Novo Men of the sugarcane fields and their hospitals: the architecture of health under the Estado Novo

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    Aborda a constituição de um patrimônio arquitetônico da saúde para a assistência ao trabalhador da agroindústria açucareira no Brasil, a partir do Estatuto da Lavoura Canavieira (1941), sob a égide do Instituto do Açúcar e do Álcool (IAA) e no âmbito da política do Estado Novo (1937-1945). Esclarece as soluções propostas pelo Instituto, fundamentadas em inquéritos realizados nas usinas de cada estado canavieiro e no sistema médico-hospitalar, de raízes norte-americanas da década de 1940, adotado pela burocracia ilustrada do IAA. Destaca os hospitais centrais de Pernambuco e especialmente de Alagoas, contrários às orientações do Instituto.<br>The article explores the emergence of an architectural heritage in the realm of healthcare assistance for workers in the sugarcane agroindustry in Brazil following enactment of the law known as the Estatuto da Lavoura Canavieira (1941), under the auspices of the Instituto do Açúcar e do Álcool and as part of Estado Novo policies (1937-1945). The institute proposed solutions based on surveys conducted at sugarcane mills in cane-producing states and on the medical and hospital system adopted by the institute's enlightened bureaucracy in the 1940s, which took the U.S. system as its model. Special focus is given to the central hospitals in Pernambuco and especially in Alagoas, which opposed institute guidelines

    Música, raça e preconceito no ensino fundamental: notas iniciais sobre hierarquia da cor entre adolescentes

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