81 research outputs found

    Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector

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    This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}andcorrespondtoanintegratedluminosityof and correspond to an integrated luminosity of 4.6\;{\rm f}{{{\rm b}}^{-1}}.ThemeasurementisperformedbyreconstructingtheboostedWorZbosonsinsinglejets.ThereconstructedjetmassisusedtoidentifytheWandZbosons,andajetsubstructuremethodbasedonenergyclusterinformationinthejetcentreofmassframeisusedtosuppressthelargemultijetbackground.ThecrosssectionforeventswithahadronicallydecayingWorZboson,withtransversemomentum. The measurement is performed by reconstructing the boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet centre-of-mass frame is used to suppress the large multi-jet background. The cross-section for events with a hadronically decaying W or Z boson, with transverse momentum {{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}andpseudorapidity and pseudorapidity |\eta |\lt 1.9,ismeasuredtobe, is measured to be {{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques

    Was There Shortening of the Interval Between Diagnosis and Treatment of Colorectal Cancer in Southern Netherlands Between 2005 and 2008?

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    Background: The Dutch Cancer Society proposed that the interval between diagnosis and start of treatment should be less than 15 working days. The purpose of this study was to determine whether the interval from diagnosis to treatment for patients with colorectal cancer (CRC) shortened between 2005 and 2008 in hospitals in southern Netherlands. Methods: Patients with CRC diagnosed in six hospitals in southern Netherlands during January to December in 2005 (n = 445) and January to July in 2008 (n = 353) were included. The time between diagnosis and start of treatment was assessed, and the proportion of patients treated within the recommended time (70 years and those with stage I disease. Substantial variation was seen among hospitals. Conclusions: Time to treatment for patients with CRC in southern Netherlands did not shorten between 2005 and 2008. The time to treatment should be reduced to meet the advice of the Dutch Cancer Society

    Legume nitrogen utilization under drought stress

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    Legumes account for around 27% of the world’s primary crop production and can be classified based on their use and traits into grain and forage legumes. Legumes can establish symbiosis with N-fixing soil bacteria. As a result, a new organ is formed, the nodule, where the reduction of atmospheric N2 into ammonia is carried out catalyzed by the bacterial exclusive enzyme nitrogenase. The process, highly energy demanding, is known as symbiotic nitrogen fixation and provides all the N needs of the plant, thus avoiding the use of N fertilizers in the context of sustainable agriculture. However, legume crops are often grown under non-fixing conditions since legume nodulation is suppressed by high levels of soil nitrogen occurring in chemically fertilized agro-environment. In addition, legumes are very sensitive to environmental stresses, being drought one of the significant constraints affecting crop production. Due to their agricultural and economic importance, scientists have carried out basic and applied research on legumes to better understand responses to abiotic stresses and to further comprehend plant–microbe interactions. An integrated view of nitrogen utilization under drought stress will be presented with particular focus on legume crops

    Social support and common mental disorder among medical students

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    INTRODUÇÃO:Diferentes formas de sofrimento psíquico têm sido identificadas em estudantes da área da saúde, em especial no curso de Medicina.OBJETIVO:Estimar a prevalência de sofrimento psíquico entre estudantes de Medicina em uma faculdade no Sudeste do Brasil e avaliar sua associação com apoio social.MÉTODO:Trata-se de um estudo transversal. Foram aplicados questionários para alunos do 1º ao 6º ano do curso de Medicina da Universidade Estadual Paulista Júlio de Mesquita Filho, investigando-se características demográficas relacionadas ao curso e à adaptação à cidade. Sofrimento psíquico foi investigado na forma de Transtorno Mental Comum (TMC), avaliado por meio do Self-Reporting Questionnaire (SRQ-20). Apoio social foi avaliado com a Escala de Apoio Social (EAS). As associações entre o desfecho e as variáveis explanatórias foram analisadas por meio do teste do χ2 e, na análise multivariada, por meio da Regressão Logística, com p < 0,05.RESULTADOS:A taxa de resposta foi de 80,7%, não havendo diferença estatística entre a mostra e a população-alvo no que diz respeito ao gênero (p = 0,78). A média de idade foi de 22 anos (desvio padrão - DP = 2,2) com predomínio de mulheres (58,2%) e estudantes que vivem com amigos (62%). A prevalência de TMC foi de 44,9% (IC95% 40,2 - 49,6). Após a análise multivariada, mantiveram-se associados a TMC: sentir-se rejeitado no último ano (p < 0,001), ter pensado ou pensar em abandonar o curso (p < 0,001) e interação, avaliada pela EAS (p = 0,002).CONCLUSÕES:A prevalência de TMC entre estudantes de Medicina mostrou-se elevada, identificando-se o apoio social insuficiente como fator de risco. Esses achados sugerem que intervenções voltadas para propiciar melhores condições de interação social entre estudantes poderiam ser benéficas, diminuindo a prevalência de TMC nesse grupo.INTRODUCTION:Different kinds of psychological distress have been identified for students in the health field, especially in the medical school.OBJECTIVE:To estimate the prevalence of mental suffering among medical students in the Southeastern Brazil and asses its association with social support.METHODS:It is a cross-sectional study. Structured questionnaires were applied for students from the 1st up to the 6th years of the medical school of Universidade Estadual Paulista Júlio de Mesquita Filho, assessing demographic variables related to aspects of graduation and adaptation to the city. Psychological suffering was defined as a common mental disorder (CMD) assessed by the Self Reporting Questionnaire (SRQ-20). Social support was assessed by the social support scale of the Medical Outcomes Study (MOS). The association between the outcome and explanatory variables was assessed by the χ2 test and Logistic Regression, for the multivariate analyses, using p < 0.05.RESULTS:The response rate was of 80.7%, with no differences between sample and the population regarding gender (p = 0.78). The average age was 22 years old (standard deviation - SD = 2.2), mainly women (58.2%) and students who were living with friends (62%). The prevalence of CMD was 44.9% (95%CI 40.2 - 49.6). After the multivariate analyses, the explanatory variables that were associated with CMD were: feeling rejected in the past year (p < 0.001), thinking about leaving medical school (p < 0.001) and interaction in the MOS scale (p = 0.002).CONCLUSIONS:The prevalence of CMD among medical students was high and insufficient social support was an important risk factor. Our findings suggest that interventions to improve social interaction among those students could be beneficial, decreasing the prevalence of CMD in this group.Hospital das Clínicas de Ribeirão PretoUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Medicina de Botucatu Departamento de Neurologia, Psicologia e PsiquiatriaUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Medicina de Botucatu Departamento de Neurologia, Psicologia e Psiquiatri

    Adequacy of public maternal care services in Brazil

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    Abstract Background In Brazil, hospital childbirth care is available to all, but differences in access and quality of care result in inequalities of maternal health. The objective of this study is to assess the infrastructure and staffing of publicly financed labor and birth care in Brazil and its adequacy according to clinical and obstetric conditions potentially associated with obstetric emergencies. Methods Nationwide cross-sectional hospital-based study “Birth in Brazil: national survey into labor and birth” conducted in 2011–2012. Data from 209 hospitals classified as public (public funding and management) or mixed (public or private funding and private management) that generate estimates for 1148 Brazilian hospitals. Interview with hospital managers provided data for the structure adequacy assessment covering four domains: human resources, medications, equipment for women emergency care and support services. We conducted analysis of the structure adequacy rate according to type of hospital (public or mixed), availability of ICU and the woman obstetric risk using the X 2 test to detect differences in categorical variables with the level of statistical significance set at p <0.05. Results Global rate of adequacy of 34.8 %: 42.2 % in public hospitals and 29.0 % in mixed hospitals (p < 0.001). Public and mixed hospitals with ICU had higher scores of adequacy than hospitals without ICU (73.3 % × 24.4 % public hospitals; 40.3 % × 10.6 % mixed hospitals). At a national level, 32.8 % of women with obstetric risk were cared for in hospitals without ICU and 29.5 % of women without risk were cared for in hospitals with ICU. Inequalities were observed with the North, Northeast and non-capital regions having the lower rates of hospitals with ICU. Conclusions The majority of maternity wards across the country have a low rate of adequacy that can affect the quality of labor and birth care. This holds true for women at high obstetric risk, who suffer the possibility of having their care compromised by failures of hospital infrastructure, and for women at low obstetric risk, who may not receive the appropriate care to support the natural evolution of their labor when in a technological hospital environment

    Search for dark matter candidates and large extra dimensions in events with a jet and missing transverse momentum with the ATLAS detector

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    A search for new phenomena in events with a high-energy jet and large missing transverse momentum is performed using data from proton-proton collisions at s√=7TeV with the ATLAS experiment at the Large Hadron Collider. Four kinematic regions are explored using a dataset corresponding to an integrated luminosity of 4.7 fb−1. No excess of events beyond expectations from Standard Model processes is observed, and limits are set on large extra dimensions and the pair production of dark matter particles

    Measurement of χ c1 and χ c2 production with √s = 7 TeV pp collisions at ATLAS

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    The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at √s = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measure

    Muon reconstruction efficiency and momentum resolution of the ATLAS experiment in proton–proton collisions at s√=7 TeV in 2010

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    This paper presents a study of the performance of the muon reconstruction in the analysis of proton?proton collisions at s√=7 TeV at the LHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of J/ψ meson and Z boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb−1 . The measured performance is compared to Monte Carlo predictions and deviations from the predicted performance are discussed.Fil: Alconada Verzini, María Josefina
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