1000 resultados para 114
Resumo:
A search for the decays of the Higgs and Z bosons to J/ψγ and Υ(nS)γ (n=1,2,3) is performed with pp collision data samples corresponding to integrated luminosities of up to 20.3fb−1 collected at s√=8TeV with the ATLAS detector at the CERN Large Hadron Collider. No significant excess of events is observed above expected backgrounds and 95% CL upper limits are placed on the branching fractions. In the J/ψγ final state the limits are 1.5×10−3 and 2.6×10−6 for the Higgs and Z bosons, respectively, while in the Υ(1S,2S,3S)γ final states the limits are (1.3,1.9,1.3)×10−3 and (3.4,6.5,5.4)×10−6, respectively.
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Searches are performed for resonant and non-resonant Higgs boson pair production in the hh→γγbb¯ final state using 20 fb−1 of proton--proton collisions at a center-of-mass energy of 8TeV recorded with the ATLAS detector at the CERN Large Hadron Collider. A 95% confidence level upper limit on the cross section times branching ratio of non--resonant production is set at 2.2 pb, while the expected limit is 1.0 pb. The corresponding limit observed for a narrow resonance ranges between 0.8 and 3.5 pb as a function of its mass.
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The results of a dedicated search for pair production of scalar partners of charm quarks are reported. The search is based on an integrated luminosity of 20.3fb−1 of pp collisions at s√=8 TeV recorded with the ATLAS detector at the LHC. The search is performed using events with large missing transverse momentum and at least two jets, where the two leading jets are each tagged as originating from c-quarks. Events containing isolated electrons or muons are vetoed. In an R-parity-conserving minimal supersymmetric scenario in which a single scalar-charm state is kinematically accessible, and where it decays exclusively into a charm quark and a neutralino, 95% confidence-level upper limits are obtained in the scalar-charm—neutralino mass plane such that, for neutralino masses below 200 GeV, scalar-charm masses up to 490 GeV are excluded.
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A search for heavy leptons decaying to a Z boson and an electron or a muon is presented. The search is based on pp collision data taken at s√=8 TeV by the ATLAS experiment at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb−1. Three high-transverse-momentum electrons or muons are selected, with two of them required to be consistent with originating from a Z boson decay. No significant excess above Standard Model background predictions is observed, and 95% confidence level limits on the production cross section of high-mass trilepton resonances are derived. The results are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 114-176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100-468 GeV are excluded.
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A measurement of the Higgs boson mass is presented based on the combined data samples of the ATLAS and CMS experiments at the CERN LHC in the H→γγ and H→ZZ→4ℓ decay channels. The results are obtained from a simultaneous fit to the reconstructed invariant mass peaks in the two channels and for the two experiments. The measured masses from the individual channels and the two experiments are found to be consistent among themselves. The combined measured mass of the Higgs boson is mH=125.09±0.21(stat.)±0.11(syst.) GeV.
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A search for a charged Higgs boson, H±, decaying to a W± boson and a Z boson is presented. The search is based on 20.3 fb−1 of proton-proton collision data at a center-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. The H± boson is assumed to be produced via vector-boson fusion and the decays W±→qq′¯ and Z→e+e−/μ+μ− are considered. The search is performed in a range of charged Higgs boson masses from 200 to 1000 GeV. No evidence for the production of an H± boson is observed. Upper limits of 31--1020 fb at 95% CL are placed on the cross section for vector-boson fusion production of an H± boson times its branching fraction to W±Z. The limits are compared with predictions from the Georgi-Machacek Higgs Triplet Model.
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A search for new phenomena in LHC proton-proton collisions at a center-of-mass energy of s√=8 TeV was performed with the ATLAS detector using an integrated luminosity of 17.3 fb−1. The angular distributions are studied in events with at least two jets; the highest dijet mass observed is 5.5 TeV. All angular distributions are consistent with the predictions of the Standard Model. In a benchmark model of quark contact interactions, a compositeness scale below 8.1 TeV in a destructive interference scenario and 12.0 TeV in a constructive interference scenario is excluded at 95% CL; median expected limits are 8.9 TeV for the destructive interference scenario and 14.1 TeV for the constructive interference scenario.
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A educação para a sexualidade nas escolas torna-se cada vez mais importante, pois os adolescentes constituem uma faixa etária muito vulnerável a comportamentos sexuais de risco, que podem vir a comprometer o seu projeto de vida futuro. O projeto de intervenção aqui apresentado tinha como principal objetivo contribuir para um aumento dos conhecimentos dos alunos, ao nível da educação para a sexualidade e, consequentemente, promover uma mudança de crenças, atitudes e comportamentos por parte dos mesmos, junto dos seus pares e familiares. Neste sentido, foi adotada a metodologia de investigação-ação (IA). Na fase de diagnóstico, o instrumento de recolha de dados predominantemente utilizado foi um questionário construído especificamente para o efeito, o qual foi aplicado a uma amostra de 114 alunos (38 raparigas; 76 rapazes) de 3.º CEB. O mesmo instrumento foi aplicado no final da intervenção - fase de avaliação. Nas respostas aos questionários iniciais, os alunos evidenciaram algum desconhecimento relativamente ao conceito de sexualidade, às causas e consequências da gravidez na adolescência e revelaram também a adoção de alguns comportamentos de risco. Para além do questionário, foi também aplicada aos alunos a técnica da caixa de perguntas. Perante as necessidades evidenciadas pelos alunos foi implementada uma formação, dedicando-se uma sessão de 45 minutos para cada tema: o que é a sexualidade; gravidez na adolescência; assédio sexual e violência na intimidade juvenil. Os resultados obtidos na fase de avaliação demonstraram que os alunos tinham adquirido um conceito de sexualidade mais correto, revelaram-se mais conscientes relativamente às causas e consequências da gravidez na adolescência, demonstraram estar mais informados sobre o assédio sexual, bem como sobre os cuidados a ter e revelaram algumas mudanças de crenças e opiniões relativamente a determinadas situações potencialmente abusivas nas relações de intimidade juvenil.
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Objective: Immunosenescence and cognitive decline are common markers of the aging process. Taking into consideration the heterogeneity observed in aging processes and the recently described link between lymphocytes and cognition, we herein explored the possibility of an association between alterations in lymphocytic populations and cognitive performance. Methods: In a cohort of cognitively healthy adults (n = 114), previously characterized by diverse neurocognitive/psychological performance patterns, detailed peripheral blood immunophenotyping of both the innate and adaptive immune systems was performed by flow cytometry. Results: Better cognitive performance was associated with lower numbers of effector memory CD4(+) T cells and higher numbers of naive CD8(+) T cells and B cells. Furthermore, effector memory CD4(+) T cells were found to be predictors of general and executive function and memory, even when factors known to influence cognitive performance in older individuals (e.g., age, sex, education, and mood) were taken into account. Conclusions: This is the first study in humans associating specific phenotypes of the immune system with distinct cognitive performance in healthy aging.
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This research aims to advance blinking detection in the context of work activity. Rather than patients having to attend a clinic, blinking videos can be acquired in a work environment, and further automatically analyzed. Therefore, this paper presents a methodology to perform the automatic detection of eye blink using consumer videos acquired with low-cost web cameras. This methodology includes the detection of the face and eyes of the recorded person, and then it analyzes the low-level features of the eye region to create a quantitative vector. Finally, this vector is classified into one of the two categories considered —open and closed eyes— by using machine learning algorithms. The effectiveness of the proposed methodology was demonstrated since it provides unbiased results with classification errors under 5%
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Review aricle
Resumo:
A fobia social é freqüente entre adolescentes, sendo importante a sua identificação e a determinação de potenciais prejuízos. OBJETIVOS: Relatar a prevalência e o impacto na escolaridade da fobia social em uma amostra de adolescentes. MÉTODOS: O inventário de fobia social (SPIN) foi administrado em 525 alunos dos ensinos fundamental e médio, de ambos os sexos, em uma escola pública e em uma particular, na cidade de Porto Alegre, Brasil, porquanto 32 foram excluídos por respostas incompletas. Foi aplicado também um questionário para identificação das características sociodemográficas da amostra. RESULTADOS: De acordo com o SPIN, 114 dos 493 alunos (23,12%) obtiveram escores iguais ou superiores a 19 pontos no referido inventário, indicando a presença de sintomas compatíveis com o diagnóstico de fobia social. As meninas tenderam a apresentar maior freqüência de transtorno de ansiedade social em relação aos meninos (p = 0,053). Não foi encontrada associação significativa entre repetência e fobia social. CONCLUSÕES: Os sintomas compatíveis com o diagnóstico de fobia social são prevalentes em adolescentes e, em virtude de seu curso crônico, podem causar sérios prejuízos nestes indivíduos. Neste estudo, não foi possível correlacionar fobia social com repetência escolar. No entanto, é de fundamental importância a identificação e o tratamento precoce deste transtorno de ansiedade.
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OBJECTIVE: Bipolar spectrum disorders (BSDs) are prevalent and frequently unrecognized and undertreated. This report describes the development and validation of the Brazilian version of the bipolar spectrum diagnostic scale (B-BSDS), a screening instrument for bipolar disorders, in an adult psychiatric population. METHOD: 114 consecutive patients attending an outpatient psychiatric clinic completed the B-BSDS. A research psychiatrist, blind to the B-BSDS scores, interviewed patients by means of a modified version of the mood module of the Structured Clinical Interview for DSM-IV ("gold standard"). Subthreshold bipolar disorders were defined as recurrent hypomania without a major depressive episode or with fewer symptoms than those required for threshold hypomania. RESULTS: The internal consistency of the B-BSDS evaluated with Cronbach's alpha coefficient was 0.89 (95% CI; 0.86-0.91). On the basis of the modified SCID, 70 patients (61.4%) of the sample received a diagnosis of BSDs. A B-BSDS screening score of 16 or more items yielded: sensitivity of 0.79 (95% CI; 0.72-0.85), specificity of 0.77 (95% CI; 0.70-0.83), a positive predictive value of 0.85 (95% CI; 0.78-0.91) and a negative predictive value of 0.70 (95% CI; 0.63-0.75). CONCLUSION: The present data demonstrate that the B-BSDS is a valid instrument for the screening of BSDs.
Resumo:
OBJETIVO: Analisar a relação entre características sociodemográficas e taxa de permanência hospitalar, entendida como a razão entre a quantidade total de dias internado e o número total de internações, em 114 pacientes reinternantes em hospital psiquiátrico estadual. MÉTODOS: Os dados demográficos referentes a sexo, idade, estado civil, nível de instrução e cor foram levantados nos prontuários médicos dos pacientes. Já dados sobre os aspectos sociais referentes a situação ocupacional, recebimento de benefício, residência, acompanhantes, visitas e telefonemas durante a internação foram colhidos por meio da aplicação de um questionário aos profissionais do hospital. RESULTADOS: A análise estatística mostrou que os sujeitos que apresentaram maior taxa de permanência hospitalar foram do sexo feminino, entre 40 e 49 anos, viúvos ou divorciados, negros, que residiam com outras pessoas e que não recebiam visitas durante o período em que se encontravam internados. CONCLUSÃO: Esses achados apontam para a existência de relação entre características sociodemográficas e taxa de permanência, sugerindo a importância da rede de apoio social na reabilitação do pacientes com história de internações recorrentes.
Resumo:
OBJECTIVES: To describe the process of translation and linguistic and cultural validation of the Evidence Based Practice Questionnaire for the Portuguese context: Questionário de Eficácia Clínica e Prática Baseada em Evidências (QECPBE). METHOD: A methodological and cross-sectional study was developed. The translation and back translation was performed according to traditional standards. Principal Components Analysis with orthogonal rotation according to the Varimax method was used to verify the QECPBE's psychometric characteristics, followed by confirmatory factor analysis. Internal consistency was determined by Cronbach's alpha. Data were collected between December 2013 and February 2014. RESULTS: 358 nurses delivering care in a hospital facility in North of Portugal participated in the study. QECPBE contains 20 items and three subscales: Practice (α=0.74); Attitudes (α=0.75); Knowledge/Skills and Competencies (α=0.95), presenting an overall internal consistency of α=0.74. The tested model explained 55.86% of the variance and presented good fit: χ2(167)=520.009; p = 0.0001; χ2df=3.114; CFI=0.908; GFI=0.865; PCFI=0.798; PGFI=0.678; RMSEA=0.077 (CI90%=0.07-0.08). CONCLUSION: confirmatory factor analysis revealed the questionnaire is valid and appropriate to be used in the studied context.