Estudo do comportamento em fadiga das ligas AA6005, AA6063 e AA6351

Aluminum alloys have shown great potential for the automotive industry, especially aluminum alloys 6xxx series. This category has good mechanical strength and excellent corrosion resistance, important for the areas of construction and transport. The automotive industry has always shown great interest in the study of fatigue behavior, because structural components are subjected to cyclic and vibration loads, generating cracks and fracturing. The mechanical response depends on the material properties, applications, surface condition and microstructure. In this work was study the fatigue behavior of high cycle of machined bodies (not polished) and the effect of roughness on the fatigue life for three aluminum alloys of 6xxx series: AA6005, AA6351 and AA606, all in the T6 condition . S / N curves were made from fatigue tests in rotating bending (R = -1). The influence of roughness was studied by measuring the roughness of each specimen. Was compare the fatigue behavior of polished specimen and not polished specimens. The fractured surfaces of samples were observed by MEV, and it was observed that most of nucleation sites for fatigue crack is initiated below the surface

Comportamento das curvas de saturação da água e LNAPL em solo da formação Rio Claro

Pós-graduação em Geociências e Meio Ambiente - IGCE

Verificação da eficiência do modelo de Mohler na resposta do comportamento de vigas mistas de madeira e concreto

The aim of this research study was to evaluate the structural behaviour of the wood and concrete composite system for bridge decks with emphasis on the metal shear connectors. Experimental tests were performed on composite specimens and wood and concrete beams with a metallic connector system in an X position, using CS100900-type screws. All specimens and beams were submitted to static loads until failure in order to obtain the strength and stiffness of the connection system. The experimental results for the stiffness of the beams were compared with the analytical results obtained through the Mohler model, presenting good equivalence for service loads. The experimental results obtained demonstrate that the most significant damage in composite systems occurred in the connectors' areas.

Métodos de coleta de deposição para ensaios de deriva em aplicações aéreas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O comportamento diante do paradigma behaviorista radical

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comportamento de sistemas de informações geográficas por meio de classificação supervisionada em diferentes bacias hidrográficas

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Comportamento do carbono orgânico e de atributos químicos, físicos e microbiológicos de um solo arenoso em área de conversão pastagem - Eucalipto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da rigidez vertical no comportamento mecânico e dimensionamento da via permanente ferroviária.

A via permanente representa um elemento imprescindível na composição do transporte ferroviário e seu desempenho deve ser adequado, de forma a garantir tanto segurança quanto conforto. Assim, diversos aspectos devem ser analisados ainda na fase de projeto, através de dimensionamentos que confrontem diferentes parâmetros da resposta da via e os limites estabelecidos. Dessa forma, o conhecimento do comportamento mecânico da via, devido aos esforços impostos pela passagem do material rodante, passa a ser essencial no projeto de uma estrutura que garanta os requisitos necessários, sem ser inviável economicamente. Visto que esse comportamento mecânico é muito sensível à rigidez vertical da estrutura, o presente trabalho apresenta análises da influência desse parâmetro na resposta da via e, consequentemente, no seu dimensionamento. Nesse contexto, o trabalho abrange tanto o caso de vias em lastro solicitadas por trens de carga, quanto o caso de vias em laje solicitadas por trens de passageiros em meios urbanos. No primeiro caso são realizados estudos paramétricos, por meio de modelos clássicos e um modelo mecanicista, para a análise de momentos fletores e deflexões nos trilhos, bem como tensões verticais nas camadas de lastro, sub-lastro e subleito. Já no segundo caso, são realizados estudos paramétricos relativos à transmissibilidade e à atenuação de vibrações causadoras de ruído secundário. Também é feita uma análise da influência da rigidez vertical na amplificação dinâmica das cargas estáticas, que pode ser aplicada a ambos os casos citados e até extrapolada para casos de vias de alta velocidade. Os resultados mostraram que aumentos de rigidez vertical resultam em ganhos do ponto de vista de momentos fletores e deflexões nos trilhos, além de maior resistência e capacidade de dissipação de tensões verticais nas camadas de lastro, sub-lastro e subleito. Por outro lado, esses aumentos também levaram a maiores tensões nas camadas subjacentes à grade citadas, além de atenuações de vibrações em menores intervalos de frequência e maiores amplificações dinâmicas das cargas estáticas em vias de alta velocidade. Assim, é mostrado que a influência da rigidez vertical, tanto da via como um todo quanto de alguns elementos específicos, não deve ser analisada de forma genérica, pois, dependendo do parâmetro da resposta da via considerado no dimensionamento, seu aumento pode representar uma influência positiva ou negativa.

Estudos sobre o comportamento do consumidor na SciELO

Los estudios de comportamiento de los consumidores han llamado la atención de investigadores de diferentes países, de diversas áreas de especialización y con objetivos variados. Este artículo es un estudio bibliométrico interdisciplinario sobre el comportamiento del consumidor en el contexto internacional (países de Iberoamérica y África del Sur) de la plataforma SciELO (ScientificElectronic Library Online). Mediante el análisis de una muestra conformada por 153 artículos, se observó que las ciencias sociales y las humanidades aplicadas son las áreas de investigación que aportan mayor cantidad de trabajos, con un predominio de las ciencias de la administración. Asimismo, se constató que la mayor parte de los aportes son de carácter empírico y proceden universidades.

Estudos sobre o comportamento do consumidor na SciELO

Los estudios de comportamiento de los consumidores han llamado la atención de investigadores de diferentes países, de diversas áreas de especialización y con objetivos variados. Este artículo es un estudio bibliométrico interdisciplinario sobre el comportamiento del consumidor en el contexto internacional (países de Iberoamérica y África del Sur) de la plataforma SciELO (ScientificElectronic Library Online). Mediante el análisis de una muestra conformada por 153 artículos, se observó que las ciencias sociales y las humanidades aplicadas son las áreas de investigación que aportan mayor cantidad de trabajos, con un predominio de las ciencias de la administración. Asimismo, se constató que la mayor parte de los aportes son de carácter empírico y proceden universidades.

Estudos sobre o comportamento do consumidor na SciELO

Los estudios de comportamiento de los consumidores han llamado la atención de investigadores de diferentes países, de diversas áreas de especialización y con objetivos variados. Este artículo es un estudio bibliométrico interdisciplinario sobre el comportamiento del consumidor en el contexto internacional (países de Iberoamérica y África del Sur) de la plataforma SciELO (ScientificElectronic Library Online). Mediante el análisis de una muestra conformada por 153 artículos, se observó que las ciencias sociales y las humanidades aplicadas son las áreas de investigación que aportan mayor cantidad de trabajos, con un predominio de las ciencias de la administración. Asimismo, se constató que la mayor parte de los aportes son de carácter empírico y proceden universidades.

Estimulação optogenética do septo medial no rato anestesiado e em livre comportamento

Theta rhythm consists of an electrophysiological hippocampal oscillation present in mammalian species (4-12 Hz with variations across species). This oscillation is present during active waking and is also prevalent in local field potentials (LFP) during rapid eye movement sleep (REM sleep). Several studies have shown that theta rhythm is important in cognitive tasks and that the medial septum is a key region for its occurrence. The septum sends cholinergic, GABAergic and glutamatergic projections to the hippocampus, which in turn projects axons to the septum. Besides the septum, other regions are involved in regulating theta rhythm, forming a complex network of interactions among brain areas that result in theta rhythm. Optogenetics is a recently developed method that has been widely used in various research areas. It allows us to manipulate the electrical activity of neurons through light stimulation. One of the existing techniques consists in using a viral vector to induce the neuronal expression of ion channels associated with the light-sensitive molecule rhodopsin (e.g. ChR2). Once infected, the neurons become sensitive to light of a particular wavelength. The present M. Sc. research aimed to perform luminous stimulation of the brain in anesthetized and freely behaving animals using chronically implanted electrodes and optical fibers in animals infected with a viral vector for ChR2 expression. Surgical viral injections were performed in the medial septum; histological results confirmed the expression of ChR2 by way of the presence of the eYFP reporter protein in the septum and also in hippocampal processes. Moreover, we performed acute experiments with luminous stimulation of the medial septum and LFP recordings of the septum and hippocampus of anesthetized animals. Action potentials were recorded in the septum. In these experiments we observed a significant increase in the firing rates of septal neurons during luminous stimulation (n = 300 trials). Furthermore, we found an early light-evoked response in the hippocampal LFP. Chronic experiments with luminous stimulation of the medial septum and hippocampus in freely behaving animals were also performed in combination with LFP recordings. We found that the luminous stimulation of the septum is able to induce theta rhythm in the hippocampus. Together, the results demonstrate that the luminous stimulation of the medial septum in optogenetically-modified animals causes relevant electrophysiological changes in the septum and the hippocampus.

Ecologia de comunidades e comportamento reprodutivo de anfíbios anuros em savana amazônica

The Amazon savannas occur as isolated patches throughout extensive areas of forest in the states of Amapá, Amazonas, Pará, and Roraima. There is a considerable variation in the composition of anuran assemblages in the localities and phytophysiognomies of Amazon savannas and given the absence of studies on reproductive behavior, a systematic and geographically wide sampling has been carried out in the Amapá savanna, located in the Eastern Amazon. The study was conducted in a savanna area in the state of Amapá to examine the composition, ecology, and reproductive behavior of anuran amphibians. We carried out 24 field trips in each phytophysiognomy (gramineous-woody savana, gramineous-herbaceous-woody savana, park savana, and arboreal savanna); for analysis of reproductive behavior observations were made during the period January to December 2013, lasting four consecutive days. Samples were collected by active and acoustic search along 20 plots of 100x50 meters. Twenty-one anuran species were recorded, of which four are new records for the state of Amapá: Dendropsophus walfordi, Scinax fuscomarginatus, Pseudopaludicola boliviana e Elachistocleis helianneae. The KruskalWallis ANOVA revealed significant differences between richness and species diversity in the phytophysiognomies (p < 0.05). The Bray-Curtis similarity coefficient divided the phytophysiognomies into three groups: arboreal savana, gramineous-woody savanna and gramineous-herbaceous-woody savanna, and park savanna. According to the non-metric multidimensional scaling, the structure of the anuran community resulted in a separation into three phytophysiognomies, with significant differences in the structure of communities (ANOSIM, R = 0.823; p < 0.001). In the study of community ecology, the results obtained for spatial, temporal, and trophic niche breadth suggest that the assemblage of anurans of the Amapá savanna is not composed of predominantly generalist species. Also, the presence of other specialist anurans may explain the processes of speciation associated with the isolation of habitats, resulting in heterogeneity and spatial discontinuity in the phytophysiognomies with open formations. The null model analysis revealed that the community is structured based on temporal and trophic niche, indicating a significant influence of contemporary ecological factors on the assemblage. The absence of structure based on spatial niche might be explained by the spatial segregation in the distribution and occupation of anurans in the different phytophysiognomies of the Amapá savanna. Regarding the reproductive behavior of anurans, 11 species were classified as having a long breeding season, intrinsically associated with the rainy season and the reproductive mode of most species that lay egg clutches in lentic water bodies. Six reproductive modes were recorded and parental care was observed in Leptodactylus macrosternum and L. podicipinus, whose reproductive mode is characterized by foam nests. Regarding behavioral reproductive strategies, calling males were observed in all species of anurans, satellite males were recorded only for D. walfordi, Hypsiboas multifasciatus, S. nebulosus and S. fuscomarginatus; active search for females was observed for Phyllomedusa hypochondrialis and L. fuscus, and male displacement was recorded only for Rhinella major and R. margaritifera. Of the reproductive behaviors observed, throat and vocal sac display is associated with courtship and territorial behavior exhibited by males. In addition to courtship behavior, visual signals associated with courtship strategies were recorded for the anurans of the Amapá savanna.

Herpetofauna associada à bromélia rupícola, encholirium spectabile, no semiárido brasileiro: revisão da literatura, ecologia das espécies e comportamento de psychosaura agmosticha (squamata: mabuyidae)

Bromeliads are an important microhabitat for the herpetofauna, for being widely used as refuge from predators and their leaf architecture allows humidity maintenance and relatively constant temperature inside, setting a favorable environment for amphibians and reptiles, especially in areas under hydric stress. However, studies addressing this relationship are still incipient and more concentrated in fitotelmatas bromeliad. For non-fitotelmatas rupicolous bromeliads of the gender Encholirium, which develops into rocky outcrops and contains species of semi-arid regions such as the Caatinga, animal-plant relationships are almost unknown. In this context, this study aimed to know the herpetological fauna inhabitant of macambiras bromeliads, Encholirium spectabile, analyzing occupation and use of these bromeliads by different taxa, and the behavioral ecology of the lizard Psychosaura agmosticha, seeking to identify factors associated with this strict relationship in Caatinga. An extensive review of the world literature on the subject “lizards in bromeliads” subsidized this study from the ecological perspective of this association. The field work was carried out at Fazenda Tanques, municipality of Santa Maria / RN, mesoregion of Agreste Potiguar. The observations and/or data collection in daytime and in the evening was conducted monthly during three consecutive days, from January 2011 to August 2012, totaling 450 hour.man of sampling effort. Sixteen species were registered: six lizards (Mabuyidae, Tropiduridae, Gekkonidae and Phyllodactylidae Families), six snakes (Boidae and Dipsadidae Families) and four of amphibians of Hylidae Family. The effect of the forest edge on the distribution of species along the outcrop was significant, with most species found in outcrop edges. Significant difference was found between some pairs of species concerning use of bromeliads, and almost total niche overlap in the use of microhabitat. 62.5% of the species are nocturnal and use these plants for sheltering, breeding and feeding. Regarding the relations between 4 the lizard Psychosaura agmosticha and macambiras bromeliads, behaviors of thermoregulation and foraging in the dry and wet seasons were recorded. Activity periods were concentrated between 7 and 10 am and between 3 and 5 pm in both seasons, showing a clear bimodal pattern. The species basically used the green leaves and there were no significant differences between males and females in the use of bromeliads. Positive associations were found between body temperature and temperatures of bromeliads and air. This species spent 1.95% ± 3.8 of the time moving (PTM) and moved on average 0:36 ± 2.1 seconds per minute (MPM), with significant differences between the wet and dry to PTM, and between the average time of stop and average duration of movements, being considered a sedentary forager. Psychosaura agmosticha, in the study area, is bromelicolous and uses macambiras primarily for thermoregulation and foraging. The results of this study elevate the rupicolous bromeliads Encholirium spectabile as key elements for the maintenance of amphibians and reptiles associated with it, and a clear advantageous association for the conservation of the groups involved.

Autocriticismo, Estima Corporal e Sintomas de Perturbação do Comportamento Alimentar em Adolescentes do Sexo Feminino, Praticantes de Ballet e Andebol

Introdução: As Perturbações do Comportamento Alimentar (PCA) constituem um grave problema de saúde pública. Poucos estudos em Portugal ligam esta temática a áreas como o autocriticismo e a estima corporal. Assim, são nossos objetivos principais: explorar, numa amostra de adolescentes do sexo feminino, as diferenças entre praticantes de ballet e praticantes de andebol, nos sintomas de PCA, índice de massa corporal (IMC), dimensões avaliativas da aparência e níveis de autocriticismo; analisar se níveis maiores de autocriticismo e uma visão mais depreciativa em termos de aparência se associam a níveis mais elevados de sintomas de PCA (nas duas modalidades desportivas). Em virtude das associações encontradas, pretendemos realizar análises preditivas, controlando a influência de sintomas de depressão, ansiedade e stress. Metodologia: A amostra é constituída por 105 adolescentes do sexo feminino (n = 52; 49,5% do ballet e n = 53; 50,5% do andebol) com idades compreendidas entre os 12 e 18 anos (M = 14,5; DP = 1,80). As participantes preencheram um protocolo composto por um questionário sociodemográfico, pela Escala de Autocriticismo e Autotranquilização (FSCRS), pelo Teste de Atitudes Alimentares-25 (TAA-25/EAT-25), pela Escala Estima Corporal (BES) e pela Escala Depressão Ansiedade e Stress (DASS-21). Resultados: Verificaram-se percentagens preocupantes de eventual PCA (ponto de corte de 19) nas praticantes de Ballet (7,7%) e de Andebol (9,4%). Quanto ao IMC, na amostra de praticantes de ballet, encontrou-se uma percentagem relevante de jovens com magreza (34,6%). As praticantes de Ballet e de Andebol apenas se diferenciaram no IMC e na dimensão FSCRS_eu inadequado (valores superiores nas praticantes de Andebol). Verificaram-se, na subamostra Ballet, associações significativas entre a Motivação para a Magreza e as formas de autocriticismo FSCRS_eu inadequado, FSCRS_eu detestado, FSCRS_eu tranquilizador e FSCRS_total e entre os Comportamentos Bulímicos e as formas de autocriticismo FSCRS_eu detestado e FSCRS_total. Na subamostra Andebol constataram-se associações significativas entre a Motivação para a Magreza e a forma de autocriticismo FSCRS_eu inadequado e FSCRS_total. A dimensão FSCRS_eu detestado mostrou predizer, na subamostra Ballet, a Motivação para a Magreza e os Comportamentos Bulímicos. Na subamostra Andebol o BES_Peso foi o preditor significativo da Motivação para a Magreza. Discussão: É preocupante a percentagem de eventual PCA (em ambas em subamostras) bem como a percentagem de jovens que praticam Ballet com um IMC indicador de magreza, principalmente por serem jovens atletas e estarem mais focadas no seu corpo e forma física, estando mais vulneráveis ao desenvolvimento da patologia. É um contributo fundamental deste trabalho verificar associações (bem como o papel preditivo) nestas duas modalidades desportivas, separadamente, entre as formas de autocriticismo e as dimensões do TAA-25 Motivação para a Magreza e Comportamentos Bulímicos. Parece essencial o desenvolvimento de ações de sensibilização junto dos professores/treinadores, com o intuito de despertar uma maior atenção para a visão crítica das suas bailarinas/atletas em relação ao seu corpo, que parece influenciar as suas atitudes alimentares. Será importante iniciar estas ações/intervenções precocemente (antes mesmo da adolescência) não esquecendo a inclusão das figuras paternas, com vista a melhorar o seu sucesso, tendo consciência que particularmente no “nicho” desportivo do ballet a imagem/aparência e o peso continuam e continuarão, muito provavelmente, a ser valorizados e reforçados. / Introduction: Eating Disorders are a major public health problem. Few studies in Portugal associate this theme with areas such as self-criticism and body esteem. Thus, our main objectives are: to explore, in a sample of female adolescents, the differences between ballet and handball practitioners as to symptoms of eating disorders, body mass index (BMI) and evaluative dimensions of appearance and self-criticism levels; to analyze whether higher levels of self-criticism and a more derogatory vision in terms of appearance are associated with higher levels of PCA symptoms (in both sports). Having these associations into account, we intend to perform predictive analysis, controlling the influence of symptoms of depression, anxiety and stress. Methodology: Our sample is composed by 105 female adolescents (n = 52; 49.5% from ballet and n = 53; 50.5% from handball) with ages between 12 and 18 years (M = 14.5; DP = 1.80). The participants filled in a protocol composed by a sociodemographic questionnaire, the Forms of Self-Criticizing and Reassuring Scale (FSCRS), the Eating Attitudes Test-25 (TAA-25/EAT-25), the Body Esteem Scale (BES) and Depression, Anxiety and Stress Scale (DASS-21). Results: There were worrying percentages of eventual PCA (cutoff of 19) in Ballet practitioners (7.7%) and Handball (9.4%). As to the BMI, in the sample of practitioners of ballet we found a significant percentage of young people with malnutrition (34.6%). Ballet and Handball practitioners only differed in BMI and in the inadequate self form (higher values in Handball practitioners). In the Ballet subsample there were significant associations between Motivation for thinness and forms of self-criticism, inadequate self form, hated self form, reassure self form and total self criticism and between Bulimic behaviors and inadequate self form and total self criticism. In the Handball subsample, significant associations were found between Motivation for thinness, the inadequate self form and total self criticism. The hated self form predicted, in the Ballet subsample, Motivation for thinness and Bulimic behaviors. In the subsample Handball BES_Weight was the significant predictor of Motivation for thinness. Discussion: The percentage of any Eating Disorders (in both subsamples) and the percentage of young people who practice ballet with a IMC indicating thinness is worrying, especially in young athletes who are more focused on their body and physical form, being more vulnerable to develop these disorders/symptoms. A major contribution of this work is to have shown the associations (as well as the predictive role), in these two sports, separately, between self-criticism forms and the TAA-25 dimensions Motivation for thinness and Bulimic behaviors. It seems essential to develop awareness-raising among teachers/trainers, in order to raise greater attention to the critical view of their dancers / athletes in relation to their body, which seems to influence their eating attitudes. It will be important to start these actions/interventions earlier (even before adolescence) not forgetting the inclusion of parents in order to improve their success, particularly in the ballet “niche”, where image/appearance and weight will most likely continue to be valued and reinforced.