1,986 research outputs found

    Traffic splitting in MPLS networks – a hierarchical multicriteria approach, Journal of Telecommunications and Information Technology, 2007, nr 4

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    In this paper we address a new hierarchical multicriteria routing model associated with a two-path traffic splitting routing method in MPLS networks whereby the bandwidth required by a given node-to-node traffic flow is divided by two disjoint paths. The model has two levels of objective functions and several constraints. An algorithmic approach is presented for calculating non-dominated solutions and selecting good compromise solutions to this problem. Also a number of computational experiments are presented

    Relationship among medical student resilience, educational environment and quality of life

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    Resilience is a capacity to face and overcome adversities, with personal transformation and growth. In medical education, it is critical to understand the determinants of a positive, developmental reaction in the face of stressful, emotionally demanding situations. We studied the association among resilience, quality of life (QoL) and educational environment perceptions in medical students. We evaluated data from a random sample of 1,350 medical students from 22 Brazilian medical schools. Information from participants included the Wagnild and Young's resilience scale (RS-14), the Dundee Ready Educational Environment Measure (DREEM), the World Health Organization Quality of Life questionnaire - short form (WHOQOL-BREF), the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI). Full multiple linear regression models were adjusted for sex, age, year of medical course, presence of a BDI score >= 14 and STAI state or anxiety scores >= 50. Compared to those with very high resilience levels, individuals with very low resilience had worse QoL, measured by overall (beta=-0.89; 95% confidence interval =-1.21 to -0.56) and medical-school related (beta=-0.85; 95% CI=-1.25 to -0.45) QoL scores, environment (beta=-6.48; 95% CI=-10.01 to -2.95), psychological (beta=-22.89; 95% CI=-25.70 to -20.07), social relationships (beta=-14.28; 95% CI=-19.07 to -9.49), and physical health (beta=-10.74; 95% CI=-14.07 to -7.42) WHOQOL-BREF domain scores. They also had a worse educational environment perception, measured by global DREEM score (beta=-31.42; 95% CI=-37.86 to -24.98), learning (beta=-7.32; 95% CI=-9.23 to -5.41), teachers (beta=-5.37; 95% CI=-7.16 to -3.58), academic self-perception (beta=-7.33; 95% CI=-8.53 to -6.12), atmosphere (beta=-8.29; 95% CI=-10.13 to -6.44) and social self-perception (beta=-3.12; 95% CI=-4.11 to -2.12) DREEM domain scores. We also observed a dose-response pattern across resilience level groups for most measurements. Medical students with higher resilience levels had a better quality of life and a better perception of educational environment. Developing resilience may become an important strategy to minimize emotional distress and enhance medical training106CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPE

    Fitting the integrated Spectral Energy Distributions of Galaxies

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    Fitting the spectral energy distributions (SEDs) of galaxies is an almost universally used technique that has matured significantly in the last decade. Model predictions and fitting procedures have improved significantly over this time, attempting to keep up with the vastly increased volume and quality of available data. We review here the field of SED fitting, describing the modelling of ultraviolet to infrared galaxy SEDs, the creation of multiwavelength data sets, and the methods used to fit model SEDs to observed galaxy data sets. We touch upon the achievements and challenges in the major ingredients of SED fitting, with a special emphasis on describing the interplay between the quality of the available data, the quality of the available models, and the best fitting technique to use in order to obtain a realistic measurement as well as realistic uncertainties. We conclude that SED fitting can be used effectively to derive a range of physical properties of galaxies, such as redshift, stellar masses, star formation rates, dust masses, and metallicities, with care taken not to over-interpret the available data. Yet there still exist many issues such as estimating the age of the oldest stars in a galaxy, finer details ofdust properties and dust-star geometry, and the influences of poorly understood, luminous stellar types and phases. The challenge for the coming years will be to improve both the models and the observational data sets to resolve these uncertainties. The present review will be made available on an interactive, moderated web page (sedfitting.org), where the community can access and change the text. The intention is to expand the text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics & Space Scienc

    Immunomodulatory activity of Tityus serrulatus scorpion venom on human T lymphocytes

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    Abstract\ud \ud Background\ud \ud Tityus serrulatus scorpion venom (TsV) contains toxins that act on K+ and Na+ channels and account for the venom’s toxic effects. TsV can activate murine peritoneal macrophages, but its effects on human lymphocytes have been poorly investigated. Considering that lymphocytes may play an important role in envenomation, we assessed whether TsV affects the expression of phenotypic (CD3, CD4, and CD8) and activation (CD69, CD25, and HLA-DR) markers, cell proliferation, and cytokine production in peripheral blood mononuclear cells.\ud \ud \ud Methods\ud Cytotoxicity of TsV was evaluated via the MTT assay. Cell proliferation, expression of phenotypic and activation markers, and release of cytokines were assessed using flow cytometry, after treatment with non-cytotoxic concentrations of TsV. The combined use of carboxyfluorescein diacetate succinimidyl ester and monoclonal antibodies against phenotypic and activation markers enabled us to simultaneously assess cell proliferation extent and cell activation status, and to discriminate among cell subpopulations.\ud \ud \ud Results\ud TsV at concentrations of 25 to 100 μg/mL were not cytotoxic towards peripheral blood mononuclear cells. TsV did not induce significant changes in lymphocyte subpopulations or in the expression of activation markers on CD4+ and CD8+ T cells. TsV inhibited the phytohemagglutinin-stimulated lymphocyte proliferation, particularly in the CD8+ CD25+ T lymphocyte subset. TsV alone, at 50 and 100 μg/mL, did not induce peripheral blood mononuclear cell proliferation, but elicited the production and release of IL-6, a proinflammatory cytokine that plays an important role in innate and adaptive immune responses.\ud \ud \ud Conclusions\ud TsV is a potential source of molecules with immunomodulatory action on human T lymphocytes.The authors would like to thank the Nucleus for Research on Animal Toxins\ud (NAP-TOXAN-USP, grant n. 12–125432.1.3), the State of São Paulo Research\ud Foundation (FAPESP, grant n. 2011/23236-4), the Coordination for the\ud Improvement of Higher Education Personnel (CAPES, ACM, JCP and SMB\ud grants) and the National Council for Scientific and Technological\ud Development (CNPq, SMB grant) for their funding of this research. We also\ud thanks to T. M. Casare-Ogasawara for the technical support. Thanks are also\ud due to the Center for the Study of Venoms and Venomous Animals (CEVAP)\ud of UNESP for enabling the publication of this special collection (CNPq\ud process 469660/2014-7)

    Renal function evaluation in patients with American Cutaneous Leishmaniasis after specific treatment with pentavalent antimonial

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    Background: Renal evaluation studies are rare in American Cutaneous Leishmaniasis (ACL). The aim of this study is to investigate whether specific treatment reverts ACL-associated renal dysfunction. Methods: A prospective study was conducted with 37 patients with ACL. Urinary concentrating and acidification ability was assessed before and after treatment with pentavalent antimonial. Results: The patients mean age was 35.6 +/- 12 years and 19 were male. Before treatment, urinary concentrating defect (U/P-osm < 2.8) was identified in 27 patients (77%) and urinary acidification defect in 17 patients (46%). No significant glomerular dysfunction was observed before and after specific ACL treatment. There was no reversion of urinary concentrating defects, being observed in 77% of the patients before and in 88% after treatment (p = 0.344). Urinary acidification defect was corrected in 9 patients after treatment, reducing its prevalence from 40% before to only 16% after treament, (p = 0.012). Microalbuminuria higher than 30 mg/g was found in 35% of patients before treatment and in only 8% after treatment. Regarding fractional excretion of sodium, potassium, calcium, phosphorus and magnesium, there was no significant difference between pre and post-treatment period. Conclusion: As previously described, urinary concentrating and acidification defects were found in an important number of patients with ACL. Present results demonstrate that only some patients recover urinary acidification capacity, while no one returned to normal urinary concentration capacity.Brazilian National Council for Scientific and Technological Development (CNPq)Brazilian National Council for Scientific and Technological Development (CNPq

    Insetos em presépios e as "formigas vestidas" de Jules Martin (1832-1906): uma curiosa manufatura paulistana do final do século XIX

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    Encontrados no Brasil desde os primórdios da colonização portuguesa, os presépios logo tiveram de adaptar-se à realidade local, circunstância muito propícia ao aparecimento de concepções heterodoxas e ao emprego de elementos exóticos da fauna e flora de cada região. Como registros envolvendo insetos são muito pouco comuns, chama a atenção que fêmeas de saúva, Atta sp. (Hymenoptera, Formicidae), tenham sido aproveitadas na composição de presépios no estado de São Paulo. Tendo subsistido pelo menos até a década 1960, os "presépios de formigas" existentes em cidades como Embu das Artes poderiam estar relacionados às "formigas vestidas" criadas por Jules Martin, curiosa manufatura paulistana do último quartel do século XIX.Present in Brazil since the beginning of Portuguese colonization, crèche nativity scenes were soon adapted to local reality, a propitious circumstance for the appearance of heterodox conceptions and the use of exotic elements of the fauna and flora peculiar to each region. As records about insects are very uncommon, it is noteworthy that females of leaf-cutting ants, Atta sp. (Hymenoptera, Formicidae), were used to compose crèche nativity scenes in São Paulo State. Having subsisted at least up to the decade of 1960, the "ant crèches" of cities such as Embu das Artes could be related to the then famous "dressed ants" created by Jules Martin, a curious manufacture of the city of São Paulo in the last quarter of the 19th century

    Metabolite Profiles of Sugarcane Culm Reveal the Relationship Among Metabolism and Axillary Bud Outgrowth in Genetically Related Sugarcane Commercial Cultivars

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    Metabolic composition is known to exert influence on several important agronomic traits, and metabolomics, which represents the chemical composition in a cell, has long been recognized as a powerful tool for bridging phenotype–genotype interactions. In this work, sixteen truly representative sugarcane Brazilian varieties were selected to explore the metabolic networks in buds and culms, the tissues involved in the vegetative propagation of this species. Due to the fact that bud sprouting is a key trait determining crop establishment in the field, the sprouting potential among the genotypes was evaluated. The use of partial least square discriminant analysis indicated only mild differences on bud outgrowth potential under controlled environmental conditions. However, primary metabolite profiling provided information on the variability of metabolic features even under a narrow genetic background, typical for modern sugarcane cultivars. Metabolite–metabolite correlations within and between tissues revealed more complex patterns for culms in relation to buds, and enabled the recognition of key metabolites (e.g., sucrose, putrescine, glutamate, serine, and myo-inositol) affecting sprouting ability. Finally, those results were associated with the genetic background of each cultivar, showing that metabolites can be potentially used as indicators for the genetic background

    Euclid preparation. TBD. Forecast impact of super-sample covariance on 3x2pt analysis with Euclid

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    Deviations from Gaussianity in the distribution of the fields probed by large-scale structure surveys generate additional terms in the data covariance matrix, increasing the uncertainties in the measurement of the cosmological parameters. Super-sample covariance (SSC) is among the largest of these non-Gaussian contributions, with the potential to significantly degrade constraints on some of the parameters of the cosmological model under study -- especially for weak lensing cosmic shear. We compute and validate the impact of SSC on the forecast uncertainties on the cosmological parameters for the Euclid photometric survey, obtained with a Fisher matrix analysis, both considering the Gaussian covariance alone and adding the SSC term -- computed through the public code PySSC. The photometric probes are considered in isolation and combined in the `3×\times2pt' analysis. We find the SSC impact to be non-negligible -- halving the Figure of Merit of the dark energy parameters (w0w_0, waw_a) in the 3×\times2pt case and substantially increasing the uncertainties on Ωm,0,w0\Omega_{{\rm m},0}, w_0, and σ8\sigma_8 for cosmic shear; photometric galaxy clustering, on the other hand, is less affected due to the lower probe response. The relative impact of SSC does not show significant changes under variations of the redshift binning scheme, while it is smaller for weak lensing when marginalising over the multiplicative shear bias nuisance parameters, which also leads to poorer constraints on the cosmological parameters. Finally, we explore how the use of prior information on the shear and galaxy bias changes the SSC impact. Improving shear bias priors does not have a significant impact, while galaxy bias must be calibrated to sub-percent level to increase the Figure of Merit by the large amount needed to achieve the value when SSC is not included.Comment: 22 pages, 13 figure
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