16,316 research outputs found

    Action for the eleven dimensional multiple M-wave system

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    We present the covariant supersymmetric and kappa-symmetric action for a system of N nearly coincident M-waves (multiple M0-brane system) in flat eleven dimensional superspace.Comment: 4+ pages, RevTeX4, no figures. V2: misprints corrected, discussion extended, references added, LaTeX, 10 pages. V3: misprints corrected. V4, extended version, 1+13 pages, to appear in JHE

    Generalized gaugings and the field-antifield formalism

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    We discuss the algebra of general gauge theories that are described by the embedding tensor formalism. We compare the gauge transformations dependent and independent of an invariant action, and argue that the generic transformations lead to an infinitely reducible algebra. We connect the embedding tensor formalism to the field-antifield (or Batalin-Vilkovisky) formalism, which is the most general formulation known for general gauge theories and their quantization. The structure equations of the embedding tensor formalism are included in the master equation of the field-antifield formalism.Comment: 42 pages; v2: some clarifications and 1 reference added; version to be published in JHE

    Supermanifolds, symplectic geometry and curvature

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    We present a survey of some results and questions related to the notion of scalar curvature in the setting of symplectic supermanifolds.Comment: Dedicated to Jaime Mu\~noz-Masqu\'e on occasion of his 65th birthda

    Supermembrane interaction with dynamical D=4 N=1 supergravity. Superfield Lagrangian description and spacetime equations of motion

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    We obtain the complete set of equations of motion for the interacting system of supermembrane and dynamical D=4 N = 1 supergravity by varying its complete superfield action and writing the resulting superfield equations in the special gauge where the supermembrane Goldstone field is set to zero. We solve the equations for auxiliary fields and discuss the effect of dynamical generation of cosmological constant in the Einstein equation of interacting system and its renormalization due to some regular contributions from supermembrane. These two effects (discussed in late 70th and 80th, in the bosonic perspective and in the supergravity literature) result in that, generically, the cosmological constant has different values in the branches of the spacetime separated by the supermembrane worldvolume.Comment: 23 pages, no figures. V2 two references added, 24 page

    The dysbindin-containing complex (BLOC-1) in brain: developmental regulation, interaction with SNARE proteins and role in neurite outgrowth.

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    Previous studies have implicated DTNBP1 as a schizophrenia susceptibility gene and its encoded protein, dysbindin, as a potential regulator of synaptic vesicle physiology. In this study, we found that endogenous levels of the dysbindin protein in the mouse brain are developmentally regulated, with higher levels observed during embryonic and early postnatal ages than in young adulthood. We obtained biochemical evidence indicating that the bulk of dysbindin from brain exists as a stable component of biogenesis of lysosome-related organelles complex-1 (BLOC-1), a multi-subunit protein complex involved in intracellular membrane trafficking and organelle biogenesis. Selective biochemical interaction between brain BLOC-1 and a few members of the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) superfamily of proteins that control membrane fusion, including SNAP-25 and syntaxin 13, was demonstrated. Furthermore, primary hippocampal neurons deficient in BLOC-1 displayed neurite outgrowth defects. Taken together, these observations suggest a novel role for the dysbindin-containing complex, BLOC-1, in neurodevelopment, and provide a framework for considering potential effects of allelic variants in DTNBP1--or in other genes encoding BLOC-1 subunits--in the context of the developmental model of schizophrenia pathogenesis

    Multivariate Anisotropic Interpolation on the Torus

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    We investigate the error of periodic interpolation, when sampling a function on an arbitrary pattern on the torus. We generalize the periodic Strang-Fix conditions to an anisotropic setting and provide an upper bound for the error of interpolation. These conditions and the investigation of the error especially take different levels of smoothness along certain directions into account

    Work activities and workers' health in broiler production: a case study

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    The objective of this study was to investigate the prevalence of health related symptoms and to analyze the work activities of workers in contracted non-mechanized broiler farms in two regions of the state of Paraná in order to determine possible factors associated to those symptoms. The methods consisted in selecting the houses and the workers, and to apply a questionnaire that included demographic data, questions related to work, the Nordic Questionnaire for Musculoskeletal Symptoms, other symptoms (runny nose, skin itching, throat and eye irritation). In addition, workers were asked if they enjoyed their job, if the supervisor motivated them to work, and if they were afraid to lose their job. Activities were submitted to systematic observations, adapted from Ergonomics, and the loads carried were analyzed and some instruments weighted. The study included 80 workers of both genders between 16 and 59 years, being 40 from each region. There were evidences of low back pain risk in the activities of filling drinkers and washing bell drinkers, with a higher prevalence in region A, where automated systems were less frequently used. The study suggests that mechanized filling of feeders, and the use of nipple drinkers may prevent health problems. It was also found that psychosocial aspects were associated to musculoskeletal symptoms. Promoting better working conditions is essential, as these aspects can affect human behavior at work.Federal University of São Paulo Department of Health SciencesState University of Campinas Department of Agriculture EngineeringFederal University of Santa Catarina Department of Production EngineeringUNIFESP, Department of Health SciencesSciEL

    Chemical Soil Attributes Evaluated By Multivariate Techniques And Geostatistics In The Area With Agroforestry And Sugarcane In Humaita, Am, Brazil

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    Studies on the spatial behavior of soil attributes in the Amazon region are still very incipient. In this sense, the objective of this work was to evaluate the chemical attributes through multivariate techniques and geoestatistics in the area with agroforestry and sugarcane in Humaita, AM, Brazil. The study was carried out in a farm in Humaita city, Amazonas State. The studied area was divided into 70.00 m x 70.00 m meshes with a regular spacing of 10 m, totaling 64 points and then, soil samples were collected at 0.0-0.2 m and 0.4-0.6 m depths. We performed chemical analyses of the attributes of soil. Then, it was applied descriptive statistics, multivariate and geostatistics. In conclusion, our findings suggest that for most of the chemical attributes was observed spatial dependence in both areas, with DSD varying from weak to moderate, with prevalence of the weak one. The multivariate analysis was efficient in the selection of chemical soil attributes that best represented the agroforestry environments and sugarcane. The results of this study will serve as a basis for further studies on these environments and other systems within the region; moreover serving as a basis for agricultural planning aiming a better environmental sustainability.326172FAPEAMSECTI-A
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