986 resultados para fluid-particle interaction
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This Letter presents a search for a heavy neutral particle decaying into an opposite-sign different-flavor dilepton pair, e±μ∓, e±τ∓, or μ±τ∓ using 20.3 fb−1 of pp collision data at s√=8 TeV collected by the ATLAS detector at the LHC. The numbers of observed candidate events are compatible with the Standard Model expectations. Limits are set on the cross section of new phenomena in two scenarios: the production of ν~τ in R-parity-violating supersymmetric models and the production of a lepton-flavor-violating Z′ vector boson.
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O presente artigo tem por objetivo validar uma versão adaptada do Partner Interaction Questionnaire (PIQ), instrumento que avalia o suporte para deixar de fumar dado pelo parceiro. É apresentada uma versão adaptada do PIQ para fumantes e abstinentes. Participaram no estudo 224 fumantes (52.7% do sexo feminino e 47.3% do sexo masculino; média de idades=28.6 anos; DP=8.69) e 169 ex-fumantes (68.6% do sexo masculino e 31.4% do sexo feminino; média de idades= 43.1 anos; DP=13.02). O instrumento apresentou boa fidelidade (alfa de Cronbach: 0.73) para a subescala positiva e para a subescala negativa (alfa de Cronbach: 0.77). O estudo de validade revelou a presença de dois fatores que explicam 43.36% da variância. O instrumento apresenta boa validade de construto, correlacionando-se positivamente com o ajustamento de casais e a qualidade de vida mental, e negativamente com a depressão. Esta versão adaptada do PIQ reuniu as condições necessárias para a sua aplicação em fumantes e ex-fumantes, podendo ser uma escala útil em programas de intervenção de cessação tabágica e de manutenção da abstinência.
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[Extrat] The advent of thc internet raised questions about the role of radio in a fast-changing media environment. Many voices forecast its end but in the summer of 2008 the Swedish Radio and TV Authority published a study named 'The Future of Radio', which clearly opposed the pessimism of recent analysis. While the study anticipates the exhaustion of the FM model, it clearly broadens perspectives for DAB and internet radio, highlighting digitalization as the key element for the future relevance of radio. The Portuguese researcher and radio professional João Paulo Meneses states that 'the future of radio relies upon the internet', calling the broad service offerings of the net the pathway for the survival of radio from the threats to its two essential aspects: rnobility and accumulation (Meneses 2008). Accumulation is radio's capability to be used in a nonexclusive manner, which means that a listener can use the radio while performing other activities, like cooking, sewing, reading, writing or jogging.
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The paper presents studies of Bose--Einstein Correlations (BEC) for pairs of like-sign charged particles measured in the kinematic range pT> 100 MeV and |η|< 2.5 in proton--proton collisions at centre-of-mass energies of 0.9 and 7 TeV with the ATLAS detector at the CERN Large Hadron Collider. The integrated luminosities are approximately 7 μb−1, 190 μb−1 and 12.4 nb−1 for 0.9 TeV, 7 TeV minimum-bias and 7 TeV high-multiplicity data samples, respectively. The multiplicity dependence of the BEC parameters characterizing the correlation strength and the correlation source size are investigated for charged-particle multiplicities of up to 240. A saturation effect in the multiplicity dependence of the correlation source size is observed using the high-multiplicity 7 TeV data sample. The dependence of the BEC parameters on the average transverse momentum of the particle pair is also investigated.
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In this study we present a new record of a plant-animal interaction: the mutualistic relationship between the specialist plant-ant Myrcidris epicharis Ward, 1990 (Pseudomyrmecinae) and its myrmecophyte host Myrcia madida McVaugh (Myrtaceae). We observed more than 50 individuals of M. madida occupied by M. epicharis in islands and margins of the Juruena River, in Cotriguaçu, Mato Grosso, Brazil (Meridional Amazon). We discuss a possible distribution of this symbiotic interaction throughout all the riparian forest of the Amazon River basin and its consequence to coevolution of the system.
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Dissertação de mestrado em Genética Molecular
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The influence of the hip joint formulation on the kinematic response of the model of human gait is investigated throughout this work. To accomplish this goal, the fundamental issues of the modeling process of a planar hip joint under the framework of multibody systems are revisited. In particular, the formulations for the ideal, dry, and lubricated revolute joints are described and utilized for the interaction of femur head inside acetabulum or the hip bone. In this process, the main kinematic and dynamic aspects of hip joints are analyzed. In a simple manner, the forces that are generated during human gait, for both dry and lubricated hip joint models, are computed in terms of the system’s state variables and subsequently introduced into the dynamics equations of motion of the multibody system as external generalized forces. Moreover, a human multibody model is considered, which incorporates the different approaches for the hip articulation, namely ideal joint, dry, and lubricated models. Finally, several computational simulations based on different approaches are performed, and the main results presented and compared to identify differences among the methodologies and procedures adopted in this work. The input conditions to the models correspond to the experimental data capture from an adult male during normal gait. In general, the obtained results in terms of positions do not differ significantly when the different hip joint models are considered. In sharp contrast, the velocity and acceleration plotted vary significantly. The effect of the hip joint modeling approach is clearly measurable and visible in terms of peaks and oscillations of the velocities and accelerations. In general, with the dry hip model, intra-joint force peaks can be observed, which can be associated with the multiple impacts between the femur head and the cup. In turn, when the lubricant is present, the system’s response tends to be smoother due to the damping effects of the synovial fluid.
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Dissertação de mestrado integrado em Engenharia de Materiais
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Tese de Doutoramento em Engenharia de Eletrónica e de Computadores
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Tese de Doutoramento em Engenharia Civil
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The supercritical fluid technology has been target of many pharmaceuticals investigations in particles production for almost 35 years. This is due to the great advantages it offers over others technologies currently used for the same purpose. A brief history is presented, as well the classification of supercritical technology based on the role that the supercritical fluid (carbon dioxide) performs in the process.
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This study aims to (a) identify and profile groups of infants according to their behavioral and physiological characteristics, considering their neurobehavioral organization, social withdrawal behavior, and endocrine reactivity to stress, and to (b) analyze group differences in the quality of mother–infant interaction. Ninety seven 8-week-old infants were examined using the Neonatal Behavioral Assessment Scale and the Alarm Distress Baby Scale. Cortisol levels were measured both before and after routine inoculation between 8 and 12 weeks. At 12 to 16 weeks mother–infant interaction was assessed using the Global Rating Scales of Mother–Infant Interaction. Three groups of infants were identified: (a) ‘‘withdrawn’’; (b) ‘‘extroverted’’; (c) ‘‘underaroused.’’ Differences between them were found regarding both infant and mother behaviors in the interaction and the overall quality of mother–infant interaction. The identification of behavioral and physiological profiles in infants is an important step in the study of developmental pathways.
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Noting that maternal depression is common during a baby's first year, this study examined the interaction of depressed and non-depressed mother-child dyads. A sample of 26 first-time mothers with postpartum depression at the third month after birth and their 3-month-old infants was compared to a sample of 25 first-time mothers with no postpartum depression at the third month after birth and their 3-month-old infants. The observations were repeated at 6 months and again at 12 months postpartum. The samples were compared for differences in mother interaction behavior, mother's infant care, mother's concern with the baby, infant behavioral difficulties, infant mental and motor development, and infant behavior with the observer. Among the findings are the following: (1) depressed mothers' interaction behavior and care of their infants are less adequate than the non-depressed mothers' interaction behavior and care of their infants at 3, 6, and 12 months postpartum; (2) infants' interaction behaviors during feeding and face-to-face interaction with depressed mothers are less adequate than infants' interactions with non-depressed mothers at 3, 6, and 12 months postpartum; (3) mother-infant interactions are less adequate in the depressed mother dyads than the non-depressed dyads at 3, 6, and 12 months postpartum; (4) depressed mothers are less concerned about their infants than non-depressed mothers at 3, 6, and 12 months postpartum; (5) infants of depressed mothers have more behavioral difficulties at 3, 6, and 12 months postpartum than infants of non-depressed mothers; (6) infants of depressed mothers had lower mental and motor development rates at 6 and 12 months postpartum than infants of non-depressed mothers; and (7) infants of non-depressed mothers behaved in a more positive way with the observer than the infants of depressed mothers. (AS)
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As Escalas de Avaliação da Interação Mãe-Bebé constituem a versão portuguesa das Interaction Rating Scales, propostas por Field (1980), e têm por objetivo avaliar a interação mãe-bebé, aos 3 meses de idade do bebé. As Escalas de Avaliação da Interação Mãe-Bebé foram administradas a 51 díades mãe-bebé aos 3, 6 e 12 meses pós-parto. A versão portuguesa das escalas mostrou elevados índices de consistência interna – Alfa de Cronbach 0,85 (IRSff bebé), 0,91 (IRSff mãe), 0,87 (IRSal bebé), 0,82 (IRSal mãe), assim como elevada fidelidade e validade concorrente e preditiva. As Escalas de Avaliação da Interação Mãe-Bebé assume-se, assim, como um instrumento robusto na avaliação da interação mãe-bebé, na situação de interação face-a-face e na situação de interação alimentar, podendo ser utilizadas em diferentes amostras e contextos, clínicos e de investigação.
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TEMA I. MECANISMOS NO CLÁSICOS EN EL CONTROL DE LA BIOSÍNTESIS DE HORMONAS TIROIDEAS. El objetivo general de este aspecto del proyecto es el estudio de los mecanismos bioquímicos y moleculares que regulan la hormonogénesis tiroidea en diferentes condiciones funcionales. En proyectos anteriores hemos demostrado que la endotoxina bacteriana lipopolisacárido (LPS) y el oxido nítrico (NO) inducen modificaciones en la biosíntesis de hormonas tiroideas. En base a estos resultados se propone investigar el mecanismo responsable de la estimulación de la captación de ioduro y la expresión de NIS ejercida por LPS y los factores que regulan la producción de NO en la célula tiroidea. Por otra parte se investigarán posibles factores hormonales reguladores de la absorción de ioduro a nivel intestinal y su relación con el eje hipófiso-tiroideo, así como los mecanismos involucrados en la expresión de NIS en enterocitos. Como extensión con aplicación clínica y en base a la experiencia del grupo en el estudio de proteínas que participan en la biosíntesis hormonal tiroidea, se realizará una pesquisa de posibles mutaciones en el transportador de ioduro en pacientes con Hipotiroidismo congénito.TEMA II. ESTUDIO DEL EFECTO DE LAS HORMONAS TIROIDEAS EN LA INICIACIÓN DE LA RESPUESTA INMUNE EN RATÓN. INTERACCIÓN CON GLUCOCORTICOIDES. En nuestro grupo demostramos recientemente un efecto novel de las hormonas tiroideas sobre la maduración/función de células presentadoras de antígenos especializadas: células dendríticas (DC), derivadas de médula ósea de ratón. En este proyecto se propone: 1) profundizar el mecanismo molecular involucrado en el efecto de triiodotironina (T3) sobre DC: rol del receptor de T3-señalamiento intracelular; capacidad de DC tratadas con T3 de estimular la citotoxicidad antígeno-específica; estrategia de vacunación en el tratamiento antitumoral. Por su parte, también previamente demostramos la característica de los glucocorticoides (GC) de interaccionar con el mecanismo de acción de las hormonas tiroideas en la expresión final de los efectos T3-específicos. Considerando el uso terapéutico de los GC en diversos estados clínico-patológicos inmunes, se propone: 2) Estudio del efecto de dexametasona (GC de síntesis) sobre el mecanismo de acción de T3 a nivel de DC.