1,581 research outputs found

    Lower Extremity Burns with Bone Exposure: Reconstruction with Dermal Regeneration Template

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    Introdução: As soluções reconstrutivas das queimaduras dos membros inferiores com exposição óssea (transferência de tecidos vascularizados) e dos defeitos do escalpe, não susceptíveis de encerramento com retalhos locais (expansão tecidual), são complexas, morosas e, por vezes, inviáveis. O recurso a substitutos cutâneos biológicos, como a matriz de regeneração dérmica, constitui uma importante alternativa às soluções reconstrutivas tradicionais. Relato dos casos: Estudo retrospectivo de 246 doentes com queimaduras dos membros inferiores, admitidos na Unidade de Queimados/Serviço de Cirurgia Plástica do nosso Centro Hospitalar, entre Janeiro de 2007 e Dezembro de 2008. Os autores apresentam 2 casos clínicos com queimaduras bilaterais das pernas e com exposição óssea. Nos dois casos, realizou-se desbridamento tangencial e encerramento das áreas cruentas com um substituto cutâneo, a matriz de regeneração dérmica. Na 4ª semana após a aplicação da matriz, o componente externo da membrana bilaminar foi substituído por enxerto de pele parcial. Obteve-se cobertura estável das áreas cruentas, sem necessidade de procedimentos cirúrgicos adicionais. Conclusões: A utilização de substitutos dérmicos expande as opções reconstrutivas nos casos de queimaduras com exposição óssea dos membros inferiores. A utilização da matriz biológica permitiu a preservação dos membros nos dois pacientes. A matriz de regeneração dérmica possibilitou uma cobertura estável de estruturas vitais, sem necessidade de transferência ou expansão tecidual e com morbilidade mínima

    Nishimori point in random-bond Ising and Potts models in 2D

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    We study the universality class of the fixed points of the 2D random bond q-state Potts model by means of numerical transfer matrix methods. In particular, we determine the critical exponents associated with the fixed point on the Nishimori line. Precise measurements show that the universality class of this fixed point is inconsistent with percolation on Potts clusters for q=2, corresponding to the Ising model, and q=3Comment: 11 pages, 3 figures. Contribution to the proceedings of the NATO Advanced Research Workshop on Statistical Field Theories, Como 18-23 June 200

    An accurate test for homogeneity of odds ratios based on Cochran's Q-statistic

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    Background: A frequently used statistic for testing homogeneity in a meta-analysis of K independent studies is Cochran's Q. For a standard test of homogeneity the Q statistic is referred to a chi-square distribution with K - 1 degrees of freedom. For the situation in which the effects of the studies are logarithms of odds ratios, the chi-square distribution is much too conservative for moderate size studies, although it may be asymptotically correct as the individual studies become large. Methods: Using a mixture of theoretical results and simulations, we provide formulas to estimate the shape and scale parameters of a gamma distribution to t the distribution of Q. Results: Simulation studies show that the gamma distribution is a good approximation to the distribution for Q. Conclusions: : Use of the gamma distribution instead of the chi-square distribution for Q should eliminate inaccurate inferences in assessing homogeneity in a meta-analysis. (A computer program for implementing this test is provided.) This hypothesis test is competitive with the Breslow-Day test both in accuracy of level and in power

    Coalescent-based genome analyses resolve the early branches of the euarchontoglires

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    Despite numerous large-scale phylogenomic studies, certain parts of the mammalian tree are extraordinarily difficult to resolve. We used the coding regions from 19 completely sequenced genomes to study the relationships within the super-clade Euarchontoglires (Primates, Rodentia, Lagomorpha, Dermoptera and Scandentia) because the placement of Scandentia within this clade is controversial. The difficulty in resolving this issue is due to the short time spans between the early divergences of Euarchontoglires, which may cause incongruent gene trees. The conflict in the data can be depicted by network analyses and the contentious relationships are best reconstructed by coalescent-based analyses. This method is expected to be superior to analyses of concatenated data in reconstructing a species tree from numerous gene trees. The total concatenated dataset used to study the relationships in this group comprises 5,875 protein-coding genes (9,799,170 nucleotides) from all orders except Dermoptera (flying lemurs). Reconstruction of the species tree from 1,006 gene trees using coalescent models placed Scandentia as sister group to the primates, which is in agreement with maximum likelihood analyses of concatenated nucleotide sequence data. Additionally, both analytical approaches favoured the Tarsier to be sister taxon to Anthropoidea, thus belonging to the Haplorrhine clade. When divergence times are short such as in radiations over periods of a few million years, even genome scale analyses struggle to resolve phylogenetic relationships. On these short branches processes such as incomplete lineage sorting and possibly hybridization occur and make it preferable to base phylogenomic analyses on coalescent methods

    Electric Field-Tuned Topological Phase Transition in Ultra-Thin Na3Bi - Towards a Topological Transistor

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    The electric field induced quantum phase transition from topological to conventional insulator has been proposed as the basis of a topological field effect transistor [1-4]. In this scheme an electric field can switch 'on' the ballistic flow of charge and spin along dissipationless edges of the two-dimensional (2D) quantum spin Hall insulator [5-9], and when 'off' is a conventional insulator with no conductive channels. Such as topological transistor is promising for low-energy logic circuits [4], which would necessitate electric field-switched materials with conventional and topological bandgaps much greater than room temperature, significantly greater than proposed to date [6-8]. Topological Dirac semimetals(TDS) are promising systems in which to look for topological field-effect switching, as they lie at the boundary between conventional and topological phases [3,10-16]. Here we use scanning probe microscopy/spectroscopy (STM/STS) and angle-resolved photoelectron spectroscopy (ARPES) to show that mono- and bilayer films of TDS Na3Bi [3,17] are 2D topological insulators with bulk bandgaps >400 meV in the absence of electric field. Upon application of electric field by doping with potassium or by close approach of the STM tip, the bandgap can be completely closed then re-opened with conventional gap greater than 100 meV. The large bandgaps in both the conventional and quantum spin Hall phases, much greater than the thermal energy kT = 25 meV at room temperature, suggest that ultrathin Na3Bi is suitable for room temperature topological transistor operation

    Predictors of linkage to care following community-based HIV counseling and testing in rural Kenya

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    Despite innovations in HIV counseling and testing (HCT), important gaps remain in understanding linkage to care. We followed a cohort diagnosed with HIV through a community-based HCT campaign that trained persons living with HIV/AIDS (PLHA) as navigators. Individual, interpersonal, and institutional predictors of linkage were assessed using survival analysis of self-reported time to enrollment. Of 483 persons consenting to follow-up, 305 (63.2%) enrolled in HIV care within 3 months. Proportions linking to care were similar across sexes, barring a sub-sample of men aged 18–25 years who were highly unlikely to enroll. Men were more likely to enroll if they had disclosed to their spouse, and women if they had disclosed to family. Women who anticipated violence or relationship breakup were less likely to link to care. Enrolment rates were significantly higher among participants receiving a PLHA visit, suggesting that a navigator approach may improve linkage from community-based HCT campaigns.Vestergaard Frandse

    Study of Bc+B_c^+ decays to the K+Kπ+K^+K^-\pi^+ final state and evidence for the decay Bc+χc0π+B_c^+\to\chi_{c0}\pi^+

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    A study of Bc+K+Kπ+B_c^+\to K^+K^-\pi^+ decays is performed for the first time using data corresponding to an integrated luminosity of 3.0 fb1\mathrm{fb}^{-1} collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 77 and 88 TeV. Evidence for the decay Bc+χc0(K+K)π+B_c^+\to\chi_{c0}(\to K^+K^-)\pi^+ is reported with a significance of 4.0 standard deviations, resulting in the measurement of σ(Bc+)σ(B+)×B(Bc+χc0π+)\frac{\sigma(B_c^+)}{\sigma(B^+)}\times\mathcal{B}(B_c^+\to\chi_{c0}\pi^+) to be (9.83.0+3.4(stat)±0.8(syst))×106(9.8^{+3.4}_{-3.0}(\mathrm{stat})\pm 0.8(\mathrm{syst}))\times 10^{-6}. Here B\mathcal{B} denotes a branching fraction while σ(Bc+)\sigma(B_c^+) and σ(B+)\sigma(B^+) are the production cross-sections for Bc+B_c^+ and B+B^+ mesons. An indication of bˉc\bar b c weak annihilation is found for the region m(Kπ+)<1.834GeV ⁣/c2m(K^-\pi^+)<1.834\mathrm{\,Ge\kern -0.1em V\!/}c^2, with a significance of 2.4 standard deviations.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-022.html, link to supplemental material inserted in the reference

    Climate change and anthropogenic intervention impact on the hydrologic anomalies in a semi-arid area : lower Zab river basin, Iraq

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    Climate change impact, drought phenomena and anthropogenic stress are of increasing apprehension for water resource managers and strategists, particularly in arid regions. The current study proposes a generic methodology to evaluate the potential impact of such changes at a basin scale. The Lower Zab River Basin located in the north of Iraq has been selected for illustration purposes. The method has been developed through evaluating changes during normal hydrological years to separate the effects of climate change and estimate the hydrologic abnormalities utilising Indicators of Hydrologic Alteration. The meteorological parameters were perturbed by applying adequate delta perturbation climatic scenarios. Thereafter, a calibrated rainfall-runoff model was used for streamflow simulations. Findings proved that climate change has a more extensive impact on the hydrological characteristics of the streamflow than anthropogenic intervention (i.e. the construction of a large dam in the catchment). The isolated baseflow is more sensitive to the precipitation variations than to the variations of the potential evapotranspiration. The current hydrological anomalies are expected to continue. This comprehensive basin study demonstrates how climate change impact, anthropogenic intervention as well as hydro-climatic drought and hydrological anomalies can be evaluated with a new methodology

    Non-pharmacological interventions for weight gain in patients with schizophrenia taking antipsychotics

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    INTRODUCTION: Schizophrenic patients have a higher prevalence of obesity than the general population. There are several factors implicated in weight gain, including poor dietary conditions, sedentary lifestyle and antipsychotic drugs use. Obesity is also associated with metabolic disturbances such as diabetes mellitus. Weight gain interventions are necessary in this population, especially non-pharmacological interventions. OBJECTIVE: To review the non-pharmacological interventions for weight gain management in patients with schizophrenia. METHODS: Eight clinical trials and four open-label studies using these interventions were found. The methodology, strength and limitations of the studies were reviewed. CONCLUSIONS: Non-pharmacological interventions seem to have an important effect on weight gain prevention and control, and should be encouraged and adapted to patients and in mental health institution's reality.INTRODUÇÃO: Pacientes com esquizofrenia têm maior prevalência de obesidade em comparação à população geral. Esse fato está relacionado a uma alimentação inadequada, ao sedentarismo e ao uso de antipsicóticos. O aumento da obesidade associa-se a diversos distúrbios metabólicos, como o diabetes melito. As intervenções para prevenção e controle do ganho de peso são necessárias nessa população, em especial as intervenções não farmacológicas. OBJETIVO: Revisar os estudos sobre intervenções não farmacológicas para prevenção e controle do ganho de peso em pacientes com esquizofrenia. MÉTODOS: Foram encontrados oito estudos controlados e quatro não controlados sobre intervenções não farmacológicas. Foi feita uma revisãosobre a metodologia e os fatores positivos e limitações dos estudos. CONCLUSÕES: As intervenções não farmacológicas parecem ter um efeito importante em termos de prevenção e controle do ganho de peso e, portanto, devem ser incentivadas e adaptadas à realidade dos pacientes e serviços de saúde., Universidade Federal de São Paulo (UNIFESP) Departamento de PsiquiatriaUNIFESP Disciplina de Endocrinologia Departamento de MedicinaUNIFESP, Depto. de PsiquiatriaUNIFESP, Disciplina de Endocrinologia Depto. de MedicinaSciEL

    Observation of Bc+ →j /ψD (∗)K (∗) decays

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    A search for the decays B+c→J/ψD(*)0K+ and B+c→J/ψD(*)+K*0 is performed with data collected at the LHCb experiment corresponding to an integrated luminosity of 3 fb−1. The decays B+c→J/ψ0K+ and B+c→J/ψD*0K+ are observed for the first time, while first evidence is reported for the B+c→JψD*+K*0 and B+c→J/ψD+K*0 decays. The branching fractions of these decays are determined relative to the B+c→J/ψπ+ decay. The B+c mass is measured, using the J/ψD0K+ final state, to be 6274.28±1.40(stat)±0.32(syst) MeV/c2. This is the most precise single measurement of the B+c mass to date
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