992 resultados para Sufficient optimality conditions
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Mestrado em Fisioterapia.
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The oxovanadium(IV) complexes [VO(acac)(2)(Hpz)].HC(pz)(3) 1.HC(pz)(3) (acac= acetylacetonate, Hpz = pyrazole, pz = pyrazoly1) and [VOCl2{HOCH2C(pz)(3)}] 2 were obtained from reaction of [VO(acac)(2)] with hydrotris(1-pyrazolyl)methane or of VCl(3)with 2,2,2-tris(1-pyrazolyl)ethanol. The compounds were characterized by elemental analysis, IR, Far-IR and EPR spectroscopies, FAB or ESI mass-spectrometry and, for 1, by single crystal X-ray diffraction analysis. 1 and 2 exhibit catalytic activity for the oxidation of cyclohexane to the cyclohexanol and cyclohexanone mixture in homogeneous system (TONS up to 1100) under mild conditions (NCMe, 24h, room temperature) using benzoyl peroxide (BPO), tert-butyl hydroperoxide (TBHP), m-chloroperoxybenzoic acid (mCPBA), hydrogen peroxide or the urea-hydrogen peroxide adduct (UHP) as oxidants. 1 and 2 were also immobilized on a polydimethylsiloxane membrane (1-PDMS or 2-PDMS) and the systems acted as supported catalysts for the cyclohexane oxidation using the above oxidants (TONs up to 620). The best results were obtained with mCPBA or BP0 as oxidant. The effects of various parameters, such as the amount of catalyst, nitric acid, reaction time, type of oxidant and oxidant-to-catalyst molar ratio, were investigated, for both homogeneous and supported systems. (C) 2012 Elsevier B.V. All rights reserved.
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Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technologies is presented as a valid option but is not yet entirely studied. This work presents the study of the remediation of ethylbenzene (EB)-contaminated soils, with different soil water and natural organic matter (NOMC) contents, using sequential SVE and BR. The obtained results allow the conclusion that: (1) SVE was sufficient to reach the cleanup goals in 63% of the experiments (all the soils with NOMC below 4%), (2) higher NOMCs led to longer SVE remediation times, (3) BR showed to be a possible and cost-effective option when EB concentrations were lower than 335 mg kgsoil −1, and (4) concentrations of EB above 438 mg kgsoil −1 showed to be inhibitory for microbial activity.
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Lighting is one of the most important factors in human interaction with the environment. Poor lighting may increase the risk of accidents and could also cause a variety of symptoms including: rapid fatigue, headaches, eyestrain, tired eyes, dry eyes, ocular surface symptoms (watery and irritated eyes), decreased concentration and stress. Specific disorders: degeneration of the sharpness of vision (blurred and double vision) and slowness in changing focus. Apart from the advantages in the health and welfare for the workers, good lighting also leads to better job performance (faster), less errors, better safety, fewer accidents and less absenteeism. The overall effect is: better productivity. Good lighting includes quantity and quality requirements, and should necessarily be appropriate to the activity/task being carried out, bearing in mind the comfort and visual efficiency of the worker.
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A 5-unit polyubiquitin gene, TTU3, was isolated from a T. thermophila genomic library and sequenced. This gene presents an extra triplet coding for Phe, a AGAGA motif and a putative HSE element in its 5'-non-coding region. The ubiquitin gene expression in this ciliate was investigated by Northern blot hybridization in conjugating cells or cells under stress conditions. Exponentially growing cells express two ubiquitin mRNAs of 0.75 and 1.8 kb and a new species of 1.4 kb is induced under hyperthermic stress. During sexual reproduction of the cells (conjugation) the 1.8-kb mRNA is still transcribed whereas the steady-state population of the 0.75 mRNA transcripts is strongly diminished. Southern blot analysis suggests that ubiquitin in T. thermophila constitutes a large family of about ten members.
Produção de bioetanol a partir de um resíduo orgânico proveniente da central de compostagem da LIPOR
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Mestrado em Engenharia Química
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A sub adult Caretta caretta was found on the 23rd August, 2014 ca. 16 nautical miles south off S. Miguel Island, Azores (Northeast Atlantic), with a large pelagic trawl hook inside its mouth. The individual was kept in a basin of sea water and sent by boat to Terceira Island following instructions by the Azores Regional Government via the Environmental Authority in order to be examined by the author and, if possible, undergo the necessary hook removal procedures. In this note, we describe the surgical procedures and how the turtle was evaluated both pre- and post-surgery.
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Este trabalho surgiu do âmbito da Tese de Dissertação do Mestrado em Energias Sustentáveis do Instituto Superior de Engenharia do Porto, tendo o acompanhamento dos orientadores da empresa Laboratório Ecotermolab do Instituto de Soldadura e Qualidade e do Instituto Superior de Engenharia do Porto, de forma a garantir a linha traçada indo de acordo aos objectivos propostos. A presente tese abordou o estudo do impacto da influência do ar novo na climatização de edifícios, tendo como base de apoio à análise a simulação dinâmica do edifício em condições reais num programa adequado, acreditado pela norma ASHRAE 140-2004. Este trabalho pretendeu evidenciar qual o impacto da influência do ar novo na climatização de um edifício com a conjugação de vários factores, tais como, ocupação, actividades e padrões de utilização (horários), iluminação e equipamentos, estudando ainda a possibilidade do sistema funcionar em regime de “Free-Cooling”. O princípio partiu fundamentalmente por determinar até que ponto se pode climatizar recorrendo único e exclusivamente à introdução de ar novo em regime de “Free-Cooling”, através de um sistema tudo-ar de Volume de Ar Variável - VAV, sem o apoio de qualquer outro sistema de climatização auxiliar localizado no espaço, respeitando os caudais mínimos impostos pelo RSECE (Decreto-Lei 79/2006). Numa primeira fase foram identificados todos os dados relativos à determinação das cargas térmicas do edifício, tendo em conta todos os factores e contributos alusivos ao valor da carga térmica, tais como a transmissão de calor e seus constituintes, a iluminação, a ventilação, o uso de equipamentos e os níveis de ocupação. Consequentemente foram elaboradas diversas simulações dinâmicas com o recurso ao programa EnergyPlus integrado no DesignBuilder, conjugando variáveis desde as envolventes à própria arquitectura, perfis de utilização ocupacional, equipamentos e taxas de renovação de ar nos diferentes espaços do edifício em estudo. Obtiveram-se vários modelos de forma a promover um estudo comparativo e aprofundado que permitisse determinar o impacto do ar novo na climatização do edifício, perspectivando a capacidade funcional do sistema funcionar em regime de “Free-Cooling”. Deste modo, a análise e comparação dos dados obtidos permitiram chegar às seguintes conclusões: Tendo em consideração que para necessidades de arrefecimento bastante elevadas, o “Free-Cooling” diurno revelou-se pouco eficaz ou quase nulo, para o tipo de clima verificado em Portugal, pois o diferencial de temperatura existente entre o exterior e o interior não é suficiente de modo a tornar possível a remoção das cargas de forma a baixar a temperatura interior para o intervalo de conforto. Em relação ao “Free-Cooling” em horário nocturno ou pós-laboral, este revelou-se bem mais eficiente. Obtiveram-se prestações muito interessantes sobretudo durante as estações de aquecimento e meia-estação, tendo em consideração o facto de existir necessidades de arrefecimento mesmo durante a estação de aquecimento. Referente à ventilação nocturna, isto é, em períodos de madrugada e fecho do edifício, concluiu-se que tal contribui para um abaixamento do calor acumulado durante o dia nos materiais construtivos do edifício e que é libertado ou restituído posteriormente para os espaços em períodos mais tardios. De entre as seguintes variáveis, aumento de caudal de ar novo insuflado e o diferencial de temperatura existente entre o ar exterior e interior, ficou demonstrado que este último teria maior peso contributivo na remoção do calor. Por fim, é ponto assente que de um modo geral, um sistema de climatização será sempre indispensável devido a cargas internas elevadas, requisitos interiores de temperatura e humidade, sendo no entanto aconselhado o “Free- Cooling” como um opção viável a incorporar na solução de climatização, de forma a promover o arrefecimento natural, a redução do consumo energético e a introdução activa de ar novo.
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OBJECTIVE: To evaluate working conditions associated with health-related quality of life (HRQL) among nursing providers. METHODS: Cross-sectional study conducted in a university hospital in the city of São Paulo, Southeastern Brazil, during 2004-2005. The study sample comprised 696 registered nurses, nurse technicians and nurse assistants, predominantly females (87.8%), who worked day and/or night shifts. Data on sociodemographic information, working and living conditions, lifestyles, and health symptoms were collected using self-administered questionnaires. The following questionnaires were also used: Job Stress Scale, Effort-Reward Imbalance (ERI) and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Ordinal logistic regression analysis using proportional odds model was performed to evaluate each dimension of the SF-36. RESULTS: Around 22% of the sample was found to be have high strain and 8% showed an effort-reward imbalance at work. The dimensions with the lowest mean scores in the SF-36 were vitality, bodily pain and mental health. High-strain job, effort-reward imbalance (ERI>1.01), and being a registered nurse were independently associated with low scores on the role emotional dimension. Those dimensions associated to mental health were the ones most affected by psychosocial factors at work. CONCLUSIONS: Effort-reward imbalance was more associated with health than high-strain (high demand and low control). The study results suggest that the joint analysis of psychosocial factors at work such as effort-reward imbalance and demand-control can provide more insight to the discussion of professional roles, working conditions and HRQL of nursing providers.
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OBJECTIVE: To assess the relationship between housing conditions and low birthweight and preterm low birthweight among low-income women. METHODS: A case-control study was conducted with post-partum women living in the city of Rio de Janeiro, Southeast Brazil, in 2003-2005. Two groups of cases, low birthweight (n=96) and preterm low birthweight infants (n=68), were compared against normal weight term controls (n=393). Housing conditions were categorized into three levels: adequate, inadequate, and highly inadequate. Covariates included sociodemographic and anthropometric characteristics, risk behaviors, violence, anxiety, satisfaction during pregnancy, obstetric history and prenatal care. RESULTS: Poor housing conditions was independently associated with low birthweight (inadequate - OR 2.3 [1.1;4.6]; highly inadequate - OR 7.6 [2.1;27.6]) and preterm low birthweight (inadequate - OR 2.2 [1.1;4.3]; highly inadequate - OR 7.6 [2.4;23.9]) and factors associated with outcomes were inadequate prenatal care and previous preterm birth. Low income and low maternal body mass index remained associated with low birthweight. CONCLUSIONS: Poor housing conditions were associated with low birthweight and preterm low birthweight.
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Soil vapor extraction (SVE) and bioremediation (BR) are two of the most common soil remediation technologies. Their application is widespread; however, both present limitations, namely related to the efficiencies of SVE on organic soils and to the remediation times of some BR processes. This work aimed to study the combination of these two technologies in order to verify the achievement of the legal clean-up goals in soil remediation projects involving seven different simulated soils separately contaminated with toluene and xylene. The remediations consisted of the application of SVE followed by biostimulation. The results show that the combination of these two technologies is effective and manages to achieve the clean-up goals imposed by the Spanish Legislation. Under the experimental conditions used in this work, SVE is sufficient for the remediation of soils, contaminated separately with toluene and xylene, with organic matter contents (OMC) below 4 %. In soils with higher OMC, the use of BR, as a complementary technology, and when the concentration of contaminant in the gas phase of the soil reaches values near 1 mg/L, allows the achievement of the clean-up goals. The OMC was a key parameter because it hindered SVE due to adsorption phenomena but enhanced the BR process because it acted as a microorganism and nutrient source.
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OBJECTIVE: To assess the association between exposure to adverse psychosocial working conditions and poor self-rated health among bank employees. METHODS: A cross-sectional study including a sample of 2,054 employees of a government bank was conducted in 2008. Self-rated health was assessed by a single question: "In general, would you say your health is (...)." Exposure to adverse psychosocial working conditions was evaluated by the effort-reward imbalance model and the demand-control model. Information on other independent variables was obtained through a self-administered semi-structured questionnaire. A multiple logistic regression analysis was performed and odds ratio calculated to assess independent associations between adverse psychosocial working conditions and poor self-rated health. RESULTS: The overall prevalence of poor self-rated health was 9%, with no significant gender difference. Exposure to high demand and low control environment at work was associated with poor self-rated health. Employees with high effort-reward imbalance and overcommitment also reported poor self-rated health, with a dose-response relationship. Social support at work was inversely related to poor self-rated health, with a dose-response relationship. CONCLUSIONS: Exposure to adverse psychosocial work factors assessed based on the effort-reward imbalance model and the demand-control model is independently associated with poor self-rated health among the workers studied.
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Worldwide formaldehyde is manipulated with diverse usage properties, since industrial purposes to health laboratory objectives, representing the economic importance of this chemical agent. Therefore, many people are exposed to formaldehyde environmentally and/or occupationally. Considering the latter, there was recommended occupational exposure limits based on threshold mechanisms, limit values and indoor guidelines. Formaldehyde is classified by the International Agency for Cancer Research (IARC) as carcinogenic to humans (group 1), since a wide range of epidemiological studies in occupational exposure settings have suggested possible links between the concentration and duration of exposure and elevated risks of nasopharyngeal cancer, and others cancers, and more recently, with leukemia. Although there are different classifications, such as U.S. EPA that classified formaldehyde as a B1 compound, probable human carcinogen under the conditions of unusually high or prolonged exposure, on basis of limited evidence in humans but with sufficient evidence in animals. Formaldehyde genotoxicity is well-known, being a direct-acting genotoxic compound positively associated for almost all genetic endpoints evaluated in bacteria, yeast, fungi, plants, insects, nematodes, and cultured mammalian cells. There are many human biomonitoring studies that associate formaldehyde occupational exposure to genomic instability, and consequently possible health effects. Besides the link with cancer, also other pathologies and symptoms are associated with formaldehyde exposure, namely respiratory disorders such as asthma, and allergic contact dermatitis. Nowadays, there are efforts to reduce formaldehyde exposure, namely indoor. Europe and United States developed more strict regulation regarding formaldehyde emissions from materials containing this agent. Despite the regulations and restrictions, formaldehyde still continues to be difficult to eliminate or substitute, being biomonitoring an important tool to control possible future health effects.
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Compositional schedulability analysis of hierarchical realtime systems is a well-studied problem. Various techniques have been developed to abstract resource requirements of components in such systems, and schedulability has been addressed using these abstract representations (also called component interfaces). These approaches for compositional analysis incur resource overheads when they abstract components into interfaces. In this talk, we define notions of resource schedulability and optimality for component interfaces, and compare various approaches.
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This paper proposes a new strategy to integrate shared resources and precedence constraints among real-time tasks, assuming no precise information on critical sections and computation times is available. The concept of bandwidth inheritance is combined with a capacity sharing and stealing mechanism to efficiently exchange bandwidth among tasks to minimise the degree of deviation from the ideal system’s behaviour caused by inter-application blocking. The proposed Capacity Exchange Protocol (CXP) is simpler than other proposed solutions for sharing resources in open real-time systems since it does not attempt to return the inherited capacity in the same exact amount to blocked servers. This loss of optimality is worth the reduced complexity as the protocol’s behaviour nevertheless tends to be fair and outperforms the previous solutions in highly dynamic scenarios as demonstrated by extensive simulations. A formal analysis of CXP is presented and the conditions under which it is possible to guarantee hard real-time tasks are discussed.