961 resultados para Secondary Impact


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Programa Doutoral em Engenharia Industrial e de Sistemas

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Due to the fact that different injection molding conditions tailor the mechanical response of the thermoplastic material, such effect must be considered earlier in the product development process. The existing approaches implemented in different commercial software solutions are very limited in their capabilities to estimate the influence of processing conditions on the mechanical properties. Thus, the accuracy of predictive simulations could be improved. In this study, we demonstrate how to establish straightforward processing-impact property relationships of talc-filled injection-molded polypropylene disc-shaped parts by assessing the thermomechanical environment (TME). To investigate the relationship between impact properties and the key operative variables (flow rate, melt and mold temperature, and holding pressure), the design of experiments approach was applied to systematically vary the TME of molded samples. The TME is characterized on computer flow simulation outputsanddefined bytwo thermomechanical indices (TMI): the cooling index (CI; associated to the core features) and the thermo-stress index (TSI; related to the skin features). The TMI methodology coupled to an integrated simulation program has been developed as a tool to predict the impact response. The dynamic impact properties (peak force, peak energy, and puncture energy) were evaluated using instrumented falling weight impact tests and were all found to be similarly affected by the imposed TME. The most important molding parameters affecting the impact properties were found to be the processing temperatures (melt andmold). CI revealed greater importance for the impact response than TSI. The developed integrative tool provided truthful predictions for the envisaged impact properties.

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Doctor of Philosophy in Marketing and Strategy

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Forest regrowth occupies an extensive and increasing area in the Amazon basin, but accurate assessment of the impact of regrowth on carbon and nutrient cycles has been hampered by a paucity of available allometric equations. We develop pooled and species-specific equations for total aboveground biomass for a study site in the eastern Amazon that had been abandoned for 15 years. Field work was conducted using randomized branch sampling, a rapid technique that has seen little use in tropical forests. High consistency of sample paths in randomized branch sampling, as measured by the standard error of individual paths (14%), suggests the method may provide substantial efficiencies when compared to traditional procedures. The best fitting equations in this study used the traditional form Y=a×DBHb, where Y is biomass, DBH is diameter at breast height, and a and b are both species-specific parameters. Species-specific equations of the form Y=a(BA×H), where Y is biomass, BA is tree basal area, H is tree height, and a is a species-specific parameter, fit almost as well. Comparison with previously published equations indicated errors from -33% to +29% would have occurred using off-site relationships. We also present equations for stemwood, twigs, and foliage as biomass components.

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The purpose of this paper aims at carrying out a study in the area of Statistics for classifying Portuguese Secondary Schools (both mainland and islands: “Azores” and “Madeira”), taking into account the results achieved by their students in both national examinations and internal assessment. The main according consists of identifying groups of schools with different performance levels by considering the sub-national public and private education systems’ as well as their respective geographic location. For this, we developed an alternative educational indicator for the so-called Secondary Education indicator rankings released since 2001 by the Portuguese media.

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As orientações de política educativa de âmbito global têm colocado no centro das suas prioridades a promoção da excelência, da qualidade e da eficácia dos sistemas de ensino e formação. Este texto propõe-se debater o impacto desta agenda na realidade educativa portuguesa a partir de um olhar sobre a política em estado prático, isto é, sobre os mecanismos de apropriação ocorridos no espaço organizacional e sua articulação com as especificidades culturais da escola. À luz deste enfoque, pretende-se compreender de que forma a cultura de escola redefine localmente a sua missão educativa, ajustando-a aos propósitos democráticos e igualitários e/ou às exigências de promoção da excelência e do mérito. Partindo da hipótese de que as dimensões culturais exercem um papel central na recontextualização das políticas educativas, procurou-se identificar no sistema educativo português o alcance de um dos rituais mais expressivos da missão da escola: os rituais de distinção dos melhores alunos. Da análise de conteúdo efetuada a cerca de 1500 documentos produzidos no contexto das escolas públicas com ensino secundário, resultou um mapeamento nacional dos rituais de distinção. As conclusões apontam para uma forte adesão das instituições com ensino secundário aos rituais de distinção ou de reconhecimento público do mérito. Contudo, nem a sua configuração nem os critérios de seleção apresentam um carácter uniforme, o que nos aponta para a existência de distintas concetualizações de excelência decorrentes das diferentes culturas de escola e do seu papel na definição da sua política e do seu critério de sucesso.

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Sirtuins (Sirts) regulate several cellular mechanisms through deacetylation of several transcription factors and enzymes. Recently, Sirt2 was shown to prevent the development of inflammatory processes and its expression favors acute Listeria monocytogenes infection. The impact of this molecule in the context of chronic infections remains unknown. We found that specific Sirt2 deletion in the myeloid lineage transiently increased Mycobacterium tuberculosis load in the lungs and liver of conditional mice. Sirt2 did not affect long-term infection since no significant differences were observed in the bacterial burden at days 60 and 120 post-infection. The initial increase in M. tuberculosis growth was not due to differences in inflammatory cell infiltrates in the lung, myeloid or CD4+ T cells. The transcription levels of IFN-?, IL-17, TNF, IL-6 and NOS2 were also not affected in the lungs by Sirt2-myeloid specific deletion. Overall, our results demonstrate that Sirt2 expression has a transitory effect in M. tuberculosis infection. Thus, modulation of Sirt2 activity in vivo is not expected to affect chronic infection with M. tuberculosis.

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The objective of this work was to assess the fine-root (≤ 2 mm diameter) production dynamics of two forest regrowths at different ages. Fine-root production was monitored by the ingrowth core method in one 18-year-old site (2 ha) and one 10-year-old site (0.5 ha), both localized in the Apeú region, Northern Pará State, Brazil. The sites were abandoned after successive shifting cultivation, beginning in 1940. Monthly production of live fine-root was similar between sites and was influenced by rainfall seasonality, with higher production during the dry season than the wet season for mass and length. However, mortality in terms of mass was higher in the 10-year-old site than in the 18-year-old site. The seasonality influenced mortality only in the 18-year old site following the pattern observed for live fine-root. The influence seasonal on mortality in terms of length was different between sites, with higher mortality during the wet season in the 10-year-old site and higher mortality during the dry season in the 18-year-old site. Specific root length was higher during the wet season and at the 10-year-old site. Fine-root production was not influenced by the chronosequence of the sites studied, probably fine-root production may have already stabilized in the sites or it depended more on climate and soil conditions. The production of fine-roots mass and length were indicators that generally showed the same pattern.

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Tuberculosis presents a myriad of symptoms, progression routes and propagation patterns not yet fully understood. Whereas for a long time research has focused solely on the patient immunity and overall susceptibility, it is nowadays widely accepted that the genetic diversity of its causative agent, Mycobacterium tuberculosis, plays a key role in this dynamic. This study focuses on a particular family of genes, the mclxs (Mycobacterium cyclase/LuxR-like genes), which codify for a particular and nearly mycobacterial-exclusive combination of protein domains. mclxs genes were found to be pseudogenized by frameshift-causing insertion(s)/deletion(s) in a considerable number of M. tuberculosis complex strains and clinical isolates. To discern the functional implications of the pseudogenization, we have analysed the pattern of frameshift-causing mutations in a group of M. tuberculosis isolates while taking into account their microbial-, patient- and disease-related traits. Our logistic regression-based analyses have revealed disparate effects associated with the transcriptional inactivation of two mclx genes. In fact, mclx2 (Rv1358) pseudogenization appears to be primarily driven by the microbial phylogenetic background, being mainly related to the Euro-American (EAm) lineage; on the other hand, mclx3 (Rv2488c) presents a higher tendency for pseudogenization among isolates from patients born on the Western Pacific area, and from isolates causing extra-pulmonary infections. These results contribute to the overall knowledge on the biology of M. tuberculosis infection, whereas at the same time launch the necessary basis for the functional assessment of these so far overlooked genes.

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OBJECTIVES: The International Narcotics Control Board released its 2005 annual report, highlighting the Brazil population as one of the largest consumers of anorectics. In Brazil, the National Health Surveillance Agency issued the resolution RDC 58/2007 in order to control the prescription and sale of such drugs. In Belém, the biggest city in the Brazilian Amazon region, this resolution came into force in 2008, leading to inspections of drugstores and magistral pharmacies. The aim of this work was to evaluate the consumption of psychotropic anorectic drugs and the impact of RDC 58/2007 on the prescription and dispensing of anorectics in drugstores and magistral pharmacies in Belém. METHODOLOGY: A retrospective quantitative and descriptive study was conducted of records from the Municipal Department of Health Surveillance of Belém, for 2005 to 2008. The differences in findings were regarded significant when p < 0.05. RESULTS: A total of 1,641 balance sheets of drugstores and magistral pharmacies were analyzed. Amfepramone was the most dispensed medication, followed by fenproporex and mazindol. The highest consumption of anorectics occurred in magistral pharmacies. In 2008, there was a significant reduction in dispensing of anorectics, in drugstores as well as in magistral pharmacies. CONCLUSIONS: This study showed that there was a decrease in the dispensing of anorectics after RDC 58/2007 came into force, and that the magistral pharmacies dispensed more of these drugs. This resolution is a remarkable tool in health control, where it is of great benefit to public health and contributes substantially to the rational use of medicines in Brazil.

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Total laparoscopic hysterectomy: impact of body mass index on outcomes

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Promoting environmental and health education is crucial to allow students to make conscious decisions based on scientific criteria. The study is based on the outcomes of an Educational Project implemented with Portuguese students and consisted of several activities, exploring pre-existent Scientific Gardens at the School, aiming to investigate the antibacterial, antitumor and anti-inflammatory properties of plant extracts, with posterior incorporation in soaps and creams. A logo and a webpage were also created. The effectiveness of the project was assessed via the application of a questionnaire (pre- and post-test) and observations of the participants in terms of engagement and interaction with all individuals involved in the project. This project increased the knowledge about autochthonous plants and the potential medical properties of the corresponding plant extracts and increased the awareness about the correct design of scientific experiments and the importance of the use of experimental models of disease. The students regarded their experiences as exciting and valuable and believed that the project helped to improve their understanding and increase their interest in these subjects and in science in general. This study emphasizes the importance of raising students’ awareness on the valorization of autochthonous plants and exploitation of their medicinal properties.

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The recent focus on the cystic fibrosis (CF) complex microbiome has led to the recognition that the microbes can interact between them and with the host immune system, affecting the disease progression and treatment routes. Although the main focus remains on the interactions between traditional pathogens, growing evidence supports the contribution and the role of emergent species. Understanding the mechanisms and the biological effects involved in polymicrobial interactions may be the key to improve effective therapies and also to define new strategies for disease control. This review focuses on the interactions between microbe-microbe and host-microbe, from an ecological point of view, discussing their impact on CF disease progression. There are increasing indications that these interactions impact the success of antimicrobial therapy. Consequently, a new approach where therapy is personalized to patients by taking into account their individual CF microbiome is suggested.

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Dissertação de mestrado em Biologia Molecular, Biotecnologia e Bioempreendedorismo em Plantas

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Dissertação de mestrado em Genética Molecular