576 research outputs found

    Classical self-forces in a space with a dispiration

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    We derive the gravitational and electrostatic self-energies of a particle at rest in the background of a cosmic dispiration (topological defect), finding that the particle may experience potential steps, well potentials or potential barriers depending on the nature of the interaction and also on certain properties of the defect. The results may turn out to be useful in cosmology and condensed matter physics.Comment: 5 pages, 4 figures, revtex4 fil

    Anticardiolipin Antibody In Recurrent Spontaneous Aborting And Fertile Women.

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    OBJECTIVE: To determine the association between the presence of anticardiolipin antibody and a history of recurrent spontaneous abortion. STUDY DESIGN: Clinical controlled study. LOCATION: Department of Gynecology and Obstetrics-University of Campinas (UNICAMP). SUBJECTS: 52 individuals with recurrent spontaneous abortion were included in Group 1 and 104 individuals with at least one live born child in Group 2. Elapsed time from last delivery to blood sampling varied from six months to two years. METHOD: Between November 1993 and November 1994, patients' blood samples were screened for anticardiolipin antibody by ELISA, as described by Triplett, Barna and Unger (1993). ANALYSIS: Chi-square and Fisher's Exact tests were used for statistical analysis. Student's "t" test was used to compare the means. RESULTS: There was no statistical difference in the presence of the anticardiolipin antibody between Group 1 (zero and 2.9%) and Group 2 (7.7 and 5.8%). CONCLUSION: There was no association between the presence of anticardiolipin antibody and recurrent spontaneous abortion.11641760176

    TOPOGRAFIA DO CONE MEDULAR EM UM GATO MOURISCO, Herpailurus yagouaroundi (Severtzow, 1858)(FELIDAE)

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    A anestesia caudal foi proposta pela primeira vez em 1926 e diversas técnicas foram desenvolvidas para anestesiar os nervos espinhais lombares e sacrais. Os métodos para anestesia epidural exigem conhecimento da anatomia da região envolvida. O objetivo deste estudo foi determinar a topografia do cone medular do gato mourisco, tornando possível a realização desta técnica anestésica em um felino silvestre de nossa fauna. Uma gata mourisca, adulta, proveniente do Zoológico Parque do Sabiá, Uberlândia-MG, foi encaminhado ao Laboratório de Pesquisa em Animais Silvestres (LAPAS), com o objetivo de determinar a topografia do cone medular para tornar possível a realização desta técnica anestésica em um felino silvestre de nossa fauna. Este animal foi fixado em solução de formol a 10%. Feita incisão de pele, os músculos da coluna vertebral foram retirados, os arcos vertebrais foram seccionados para visualização da medula espinhal e seus envoltórios. O cone medular neste animal iniciou-se na sexta vértebra lombar (L6) e terminou na segunda vértebra sacral (S2), com comprimento total de 50mm. O comprimento corporal deste felino foi de 473mm. Conclui-se que o melhor local para a anestesia epidural do membro pélvico no gato mourisco está entre as vértebras L6 e S2. Topographycal study on the medullar cone in jaguarundi, Herpailurus yagouaroundi (Severtzow,1858)(FELIDAE Abstract Since the caudal anesthesia was first proposed in 1926 many techniques were developed to anesthethize the lumbar and sacral nerves. Such methods for epidural anesthesia require knowledge of the relative anatomical regions. The objetive of the present study was to determine the topographic anatomy of the jaguarundi medullar cone as a morphological basis for application of anesthesis techniques. One adult female jaguarondi that perished by natural death has been obtained form the Sabiá Zoo Park, Uberlândia, MG, Brazil and conducted to tha Wild Animals Laboratory. The animal was fixes in 10% formalin solution. Following skin incision, muscles of the vertebral column were removed and the vertebral arcs sectioned for the visualization of hte spinal cord and its wrappers. Epidural anesthesic drug in the medullar cone. The medullar cone in this jaguarundi startet in the sixth lumbar vertebra (L6) and ended in the second sacral vertebra (S2); the spinal cord length was 50mm. The corporal length of this feline measured 473mm. The best region to perform the pelvic anesthesia in a jaguarundi is between the vertebra L6 and S2

    Graviton Excitations and Lorentz-Violating Gravity with Cosmological Constant

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    Motivated by the interest raised by the problem of Lorenz-symmetry violating gauge theories in connetion with gravity models, this contribution sets out to provide a general method to systematically study the excitation spectrum of gravity actions which include a Lorentz-symmetry breaking Chern-Simons-type action term for the spin connection. A complete set of spin-type operators is found which accounts for the (Lorentz) violation parameter to all orders and graviton propagators are worked out in a number of different situations

    Reliability and validity of a questionnaire for physical activity assessment in South American children and adolescents: The SAYCARE Study

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    ABSTRACT: The objective of this article is to test the reliability and validity of the new and innovative physical activity (PA) questionnaire. Methods: Subsamples from the South American Youth/Child Cardiovascular and Environment Study (SAYCARE) study were included to examine its reliability (children: n 5 161; adolescents: n 5 177) and validity (children: n 5 82; adolescents: n 5 60). The questionnaire consists of three dimensions of PA (lei-sure, active commuting, and school) performed during the last week. To assess its validity, the subjects wore accelerometers for at least 3 days and 8 h/d (at least one weekend day). The reliability was analyzed by correlation coefficients. In addition, Bland-Altman analysis and a multilevel regression were applied to estimate the measurement bias, limits of agreement, and influence of contextual variables. Results: In children, the questionnaire showed consistent reliability (q 5 0.56) and moderate validity (q 5 0.46), and the contextual variable variance explained 43.0% with 222.9 min/d bias. In adolescents, the reliability was higher (q 5 0.76) and the validity was almost excellent (q 5 0.88), with 66.7% of the variance explained by city level with 16.0 min/d PA bias. Conclusions: The SAYCARE PA questionnaire shows acceptable (in children) to strong (in adolescents) reliability and strong validity in the measurement of PA in the pediatric population from low- to middle-income countries
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