992 resultados para Reproductive function


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X-ray reflectivity of bovine and sheep surfactant-associated protein B (SP-B) monolayers is used in conjunction with pressure-area isotherms and protein models to suggest that the protein undergoes changes in its tertiary structure at the air/water interface under the influence of surface pressure, indicating the likely importance of such changes to the phenomena of protein squeeze out as well as lipid exchange between the air-water interface and subphase structures. We describe an algorithm based on the well-established box- or layer-models that greatly assists the fitting of such unknown scattering-length density profiles, and which takes the available instrumental resolution into account. Scattering-length density profiles from neutron reflectivity of bovine SP-B monolayers on aqueous subphases are shown to be consistent with the exchange of a large number of labile protons as well as the inclusion of a significant amount of water, which is partly squeezed out of the protein monolayer at elevated surface pressures.

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Arguably the most complex conical functions are seated in human cognition, the how and why of which have been debated for centuries by theologians, philosophers and scientists alike. In his best-selling book, An Astonishing Hypothesis: A Scientific Search for the Soul, Francis Crick refined the view that these qualities are determined solely by cortical cells and circuitry. Put simply, cognition is nothing more, or less, than a biological function. Accepting this to be the case, it should be possible to identify the mechanisms that subserve cognitive processing. Since the pioneering studies of Lorent de No and Hebb, and the more recent studies of Fuster, Miller and Goldman-Rakic, to mention but a few, much attention has been focused on the role of persistent neural activity in cognitive processes. Application of modern technologies and modelling techniques has led to new hypotheses about the mechanisms of persistent activity. Here I focus on how regional variations in the pyramidal cell phenotype may determine the complexity of cortical circuitry and, in turn, influence neural activity. Data obtained from thousands of individually injected pyramidal cells in sensory, motor, association and executive cortex reveal marked differences in the numbers of putative excitatory inputs received by these cells. Pyramidal cells in prefrontal cortex have, on average, up to 23 times more dendritic spines than those in the primary visual area. I propose that without these specializations in the structure of pyramidal cells, and the circuits they form, human cognitive processing would not have evolved to its present state. I also present data from both New World and Old World monkeys that show varying degrees of complexity in the pyramidal cell phenotype in their prefrontal cortices, suggesting that cortical circuitry and, thus, cognitive styles are evolving independently in different species.

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Low temperature during panicle development in rice increases spikelet sterility. This effect is exacerbated by high rates of nitrogen (N) application in the field. Spikelet sterility induced by low temperature and N fertilisation was examined in glasshouse experiments to clarify the mechanisms involved. In two glasshouse experiments, 12-h periods of low (18/13degreesC) and high (28/23degreesC) day/night temperatures were imposed over periods of 5-7 days during panicle development, to determine the effects of low temperature and N fertilisation on spikelet sterility. In one experiment, 50% sunlight was imposed together with low temperature to investigate the additive effects of reduced solar radiation and low temperature. The effect of increased tillering due to N fertilisation was examined by a tiller removal treatment in the same experiment. Pollen grain number and spikelet sterility were recorded at heading and harvest, respectively. Although there was no significant effect of low temperature on spikelet sterility in the absence of applied N, low temperature greatly increased spikelet sterility as a result of a reduction in the number of engorged pollen grains per anther in the presence of applied N. Spikelet sterility was strongly correlated with the number of engorged pollen grains per anther. Low temperature during very early ( late stage of spikelet differentiation-pollen mother cell stage) and peak ( second meiotic division stage-early stage of extine formation) microspore development caused a severe reduction in engorged pollen production mainly as a result of reduced total pollen production. Unlike low temperature, the effect of shading was rather small. The increased tillering due to application of high rates of N, increased both spikelet number per plant and spikelet sterility under low temperature conditions. The removal of tillers as they appeared reduced the number of total spikelets per plant and maintained a large number of engorged pollen grains per anther which, in turn, reduced spikelet sterility. The number of engorged pollen grains per anther determined the numbers of intercepted and germinated pollen grains on the stigma. It is concluded that N increased tillering and spikelet number per plant and this, in turn, reduced the number of engorged pollen grains per anther, leading into increased spikelet sterility under low temperature condition.

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A utiliza????o da matriz do QFD (em portugu??s, Desdobramento da Fun????o Qualidade) como entrada para o planejamento estrat??gico regional solidificou o entendimento da Diretoria Regional sobre as expectativas dos clientes ante seus principais processos, avaliados por meio de pesquisa externa realizada bianualmente. Direcionou as a????es a serem tomadas por meio da prioriza????o, da tradu????o e do desdobramento dos requisitos mais importantes para os clientes em todos os n??veis dos processos, alinhando essas a????es com as estrat??gias, a pol??tica da qualidade e o or??amento. Da mesma forma, serviu para estabelecer metas globais de satisfa????o por segmento, de forma mais estruturada, sistematizando a avalia????o dos resultados e focando sempre a satisfa????o dos clientes cujos resultados j?? se comprovaram: ??ndice de 8,6 em 2000 para 9,2 em 2004

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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, 2016.

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This work presents a reflection on Design education and specifically on the role of Drawing in this area. As a subject, Design has expanded its field of action expanding into new areas such as Experience Design or Service Design. It became necessary for the designer to have more than an education based on technological knowledge or know-how. Many authors like Meredith Davis, Don Norman or Jamie Hobson point out the urgency to review the curricula of Design courses because nowadays “… design is more than appearance, design is about interaction, about strategy and about services. Designers change social behavior” (Norman 2011). When shifting from a product-centered design to a person-centered design (in a structure, a service or in a relationship) what should the function of drawing in a design course be? What should its curriculum be? Our work methodology will be to confront today’s perspectives on design theory and practice in an attempt to add to the discussion on the methodological strategies in design teaching in the contemporary context.

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This work presents a reflection on Design education and specifically on the role of Drawing in this area. As a subject, Design has expanded its field of action expanding into new areas such as Experience Design or Service Design. It became necessary for the designer to have more than an education based on technological knowledge or know-how. Many authors like Meredith Davis, Don Norman or Jamie Hobson point out the urgency to review the curricula of Design courses because nowadays “ … design is more than appearance, design is about interaction, about strategy and about services. Designers change social behavior” (Norman, 2011) When shifting from a product-centered design to a person-centered design (in a structure, a service or in a relationship) what should the function of drawing in a design course be? What should its curriculum be? Our work methodology will be to confront today’s perspectives on design theory and practice in an attempt to add to the discussion on the methodological strategies in design teaching in the contemporary context.

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Poly(vinylidene fluoride)/Pb(Zr0.53Ti0.47)O3,([PVDF]1−x/[PZT]x) composites of volume fractions x and (0–3) type connectivity were prepared in the form of thin films. PZT powders with average grain sizes of 0.2, 0.84, and 2.35 μm in different volume fraction of PZT up to 40 % were mixed with the polymeric matrix. The influence of the inorganic particle size and its content on the thermal degradation properties of the composites was then investigated by means of thermo-gravimetric analysis. It is observed that filler size affects more than filler concentration the degradation temperature and activation energy of the polymer. In the same way and due to their larger specific area, smaller particles leave larger solid residuals after the polymer degradation. The polymer degradation mechanism is not significantly modified by the presence of the inorganic fillers. On the other hand, an inhibition effect occurs due to the presence of the fillers, affecting particularly the activation energy of the process.

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There are basic misunderstandings on derivative markets. Some professionals believe that they are a kind of casinos and have no utility for the investors. This work looks at the effects of options introduction in the Brazilian market, seeking for another benefit for this introduction: changes in the stocks risk leveI. Our results are the same found in the US and other markets: the options introduction reduces the stocks volatility. We also found that there is a slight indication that the volatility becames more stochastic with this alternative.

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Renal scintigraphy with 99mTc-dimercaptosuccinic acid (99mTc-DMSA) is performed with the aim of detect cortical abnormalities related to urinary tract infection and accurately quantify relative renal function (RRF). For this quantitative assessment Nuclear Medicine Technologist should draw regions of interest (ROI) around each kidney (KROI) and peri-renal background (BKG) ROI, although, controversy still exists about BKG-ROI. The aim of this work was to evaluate the effect of the normalization procedure, number and location of BKG-ROI on the RRF in 99mTc-DMSA scintigraphy.

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Cerebral vascular disease is the primary cause of permanent disability in Portugal. Impaired stability is considered an important feature after stroke as it is related with higher risk of falls and functional dependence. Physiotherapy intervention usually starts early after stroke in order to direct motor recovery and help patients to improve their ability to perform activities of daily living (ADL). Purpose: to investigate the relationship of balance to functionality in acute stroke patients. Methods: 16 subjects (8 women and 8 men), mean age 63,62 ± 2,16y, with unilateral ischemic stroke in the middle cerebral artery territory, who were admitted to physiotherapy department of Fernando Fonseca Hospital in Portugal, within the first month after stroke were recruited to participate in this study. All subjects have no cognitive impairment according to Mini Mental State, no history of lower extremity orthopedic problems and no other disease that could interfere with treatments. All patients gave their inform consent to participate in this study. Subjects were assessed with the Modified Barthel Index (MBI) and the Berg Balance Scale (BBS).

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OBJECTIVE: To assess the behavior of induced abortion as a function of certain demographic variables, for the population of fertile women (15 to 49 years old) residing in the Vila Madalena subdistrict S. Paulo (Brazil). MATERIAL AND METHOD: Two population samples were selected. One sample, with 996 women, investigated the incidence of induced abortions during 1987, using the RRT. In the other, involving 1,004 women, the same information was detected through a conventional approach. In both samples, the induced abortion occurring during the reproductive life was recorded in direct fashion. Though this analysis refers only to information about past abortions, that is by 2,000 women -, it should be noted that it is exactly the RRT that lends credibility to the found or results given results. CONCLUSION: The analysis furnishes evidence showing that single women, young women between the ages of 15 and 19, women who have not had live births, women who have a number of children below the expected ideal, women who use contraceptive methods (especially inefficient ones) and women who do not have any restrictions as to abortion constitute the categories most inclined to resort to induced abortion. This grouping suggests the existence of interrelationships between categories, that is, each of these categories is probably composed primarily of the same women, those who are at the beginning of their reproductive lives.

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INTRODUCTION: After the era of rubella vaccine, cytomegalovirus (CMV) infection is one of the most frequently causes of mental retardation and congenital deafness. Seroepidemiological studies are necessary to understand the transmission dynamics of the disease. The purpose of the study was to quantify the transmission rate of CMV disease in a community in the state of São Paulo, Brazil. METHODS: Using ELISA test (IgG), a retrospective serological survey looking for CMV antibodies was performed in an non-immunized community. Frozen sera from 443 individuals, randomly selected by cluster sampling technique in the town of Caieiras, São Paulo, were collected from November 1990 to January 1991. Seroprevalence was stratified by age (0-40 years). Mathematical techniques were applied to determine the age-dependent decay function of maternal antibodies during the first year of life, the age-dependent seroprevalence function and the force of infection for CMV in this community. RESULTS: It was observed a descending phase of seropositivity in the first 9 months, but changes in antibody titration were observed between 8 months old and one year of age. The average age of the first infection was 5.02 months of age and 19.84 years, when the age-dependent seroprevalence and the force of infection were analyzed between 10 months of age and 10 years of age and from 10 to 40 years old, respectively. CONCLUSION: CMV infection is highly prevalent among the population studied and infection occurs in the first year of life. This study shows that most women at reproductive age are vulnerable to the first infection, increasing the risk for congenital infection.

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Introduction - Cerebrovascular diseases, and among them, cerebral vascular accidents, are one of the main causes of morbidity and disability at European Union countries. Clinical framework resulting from these diseases include important limitations in functional ability of the these patients Postural control dysfunctions are one of the most common and devastating consequences of a stroke interfering with function and autonomy and affecting different aspects of people’s life and contributing to decrease quality of life. Neurological physiotherapy plays a central role in the recovery of movement and posture, however it is necessary to study the efficacy of techniques that physiotherapists use to treat these problems. Objectives - The aim of this study was to investigate the effects of a physiotherapy intervention program, based on oriented tasks and strengthening of the affected lower limb, on balance and functionality of individuals who have suffered a stroke. In addition our study aimed to investigate the effect of strength training of the affected lower limb on muscle tone.

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OBJECTIVE: To evaluate possible adverse reproductive outcomes in an area adjacent to a petrochemical plant in southern Brazil. METHODS: A review of 17,113 birth records of the main hospital of the municipality of Montenegro, southern Brazil, from 1983 to 1998 was carried out. Three groups of cases were selected: (1) newborns with major congenital malformations; (2) newborns with low birth weight (<2,500 g); and (3) stillborns (>500 g). A control was assigned to each case. Controls were the first newborns weighing > or = 2,500 g without malformations and of case-matching sex. Mother's residence during pregnancy was used as an exposure parameter. Statistical analyses were performed using Chi-square test or Fisher test, odds ratio, 0.05 significance level, and 95% confidence interval. RESULTS: For unadjusted analysis, it was found a correlation between low birth weight and geographical proximity of mother's residence to the petrochemical plant (OR = 1.66; 95% CI = 1.01--2.72) or residence on the way of preferential wind direction (OR = 1.62; 95% CI = 1.03--2.56). When other covariates were added in the conditional logistic regression (maternal smoking habits, chronic disease and age), there was no association. CONCLUSIONS: Despite final results were negative, low birth weight could be a good parameter of environmental contamination and should be closely monitored in the studied area.