Measurement of the t(t)over-bar production cross section in the dilepton channel in pp collisions at √s=8 TeV

The top-antitop quark (t (t) over bar) production cross section is measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 fb(-1). The measurement is performed by analysing events with a pair of electrons or muons, or one electron and one muon, and at least two jets, one of which is identified as originating from hadronisation of a bottom quark. The measured cross section is 239 +/- 2 (stat.) +/- 11 (syst.) +/- 6 (lum.) pb, for an assumed top-quark mass of 172.5 GeV, in agreement with the prediction of the standard model

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Measurement of the t t-bar production cross section in the dilepton channel in pp collisions at sqrt(s) = 7 TeV

The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of sigma[t t-bar] for a top-quark mass of 172.5 GeV is 161.9 +/- 2.5 (stat.) +5.1/-5.0 (syst.) +/- 3.6(lumi.) pb, consistent with the prediction of the standard model.Comment: Replaced with published version. Included journal reference and DO

Combined search for the quarks of a sequential fourth generation

Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV

The production of b jets in association with a Z/gamma* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive cross section for Z/gamma* + b-jet production is measured in a sample corresponding to an integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross section with Z/gamma* to ll (where ll = ee or mu mu) for events with the invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.) +(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also studied and found to be in agreement with the predictions made by the MadGraph event generator with the parton shower and the hadronisation performed by PYTHIA.Comment: Submitted to the Journal of High Energy Physic

PROTAGONISMO DO ENFERMEIRO NO PROCESSO DE CICATRIZAÇÃO DAS FERIDAS CRÔNICAS: UM ENSAIO DA LITERATURA

Introduction: Chronic wounds are a type of lesion that has its healing process stagnated for a period of six weeks or more, despite adequate treatment. Objectives: to understand the role of nurses in the assessment and treatment of chronic wounds and to describe their performance in the face of the systematization of nursing care in the care process. Methodology: This is a literature search with a qualitative approach. The data were collected in a virtual database. For this purpose, the Virtual Health Library (VHL) was used, in the following information base: LILACS; BDENF and MEDLINE in the period from March to April 2021. After the association of all descriptors, 85 articles were found, 70 were excluded and 15 articles were selected. Results and Discussion: After reflective reading and repetition of the themes developed in the articles found, two categories emerged: the role of the nurse in the assessment and treatment of chronic wounds and the role of the nurse in the systematization of nursing care in the care process. Conclusion: It is concluded that it is of great relevance that the dermatologist nurse has theoretical and scientific knowledge about chronic wounds for implementation in practice and, thus, to meet the demands arising from the patient, considering that, care for the patient with a chronic wound needs to be holistically targeted.Introducción: Las heridas crónicas son un tipo de lesión que tiene su proceso de cicatrización estancado por un período de seis semanas o más, a pesar de un tratamiento adecuado. Objetivos: comprender el papel del enfermero en la evaluación y tratamiento de las heridas crónicas y describir su desempeño frente a la sistematización del cuidado de enfermería en el proceso asistencial. Metodología: Se trata de una búsqueda bibliográfica con enfoque cualitativo. Los datos se recopilaron en una base de datos virtual. Para ello se utilizó la Biblioteca Virtual en Salud (BVS), en la siguiente base de información: LILACS; BDENF y MEDLINE en el período de marzo a abril de 2021. Tras la asociación de todos los descriptores, se encontraron 85 artículos, se excluyeron 70 y se seleccionaron 15 artículos. Resultados y Discusión: Luego de la lectura reflexiva y repetición de los temas desarrollados en los artículos encontrados, surgieron dos categorías: el rol del enfermero en la evaluación y tratamiento de las heridas crónicas y el rol del enfermero en la sistematización del cuidado de enfermería en el cuidado. proceso. Conclusión: Se concluye que es de gran relevancia que el enfermero dermatólogo cuente con conocimientos teóricos y científicos sobre las heridas crónicas para su implementación en la práctica y, así, atender las demandas que surjan del paciente, considerando que, el cuidado del paciente con una enfermedad crónica. La herida debe ser dirigida de manera integral.Introdução: As feridas crônicas constituem-se um tipo de lesão que tem seu processo de cicatrização estagnado por um período de seis semanas ou mais, apesar do tratamento adequado. Objetivos: compreender o protagonismo do enfermeiro frente à avaliação e tratamento de feridas crônicas e descrever a sua atuação diante a sistematização da assistência de enfermagem no processo do cuidado. Metodologia: Trata-se de uma pesquisa bibliográfica de abordagem qualitativa. Os dados foram coletados em base de dados virtuais. Para tal utilizou-se a Biblioteca Virtual de Saúde (BVS), na seguinte base de informação: LILACS; BDENF e MEDLINE no período de março e abril de 2021. Após a associação de todos os descritores foram encontrados 85 artigos, excluídos 70 e selecionados 15 artigos. Resultados e Discussão: Posterior à leitura reflexiva e repetição das temáticas desenvolvidas nos artigos encontrados, emergiram duas categorias: Protagonismo do enfermeiro frente à avaliação e tratamento de feridas crônicas e Atuação do enfermeiro frente a Sistematização da Assistência de Enfermagem no processo do cuidado. Conclusão: Conclui-se que é de grande relevância que o enfermeiro dermatologista tenha conhecimento teórico-cientifico sobre as feridas crônicas para implementação na prática e assim, atender as demandas advindas do paciente, tendo em vista que, o cuidado com o paciente com ferida crônica precisa ser direcionado de forma holística. &nbsp

Search for supersymmetry in events with b-quark jets and missing transverse energy in pp collisions at 7 TeV

Results are presented from a search for physics beyond the standard model based on events with large missing transverse energy, at least three jets, and at least one, two, or three b-quark jets. The study is performed using a sample of proton-proton collision data collected at sqrt(s) = 7 TeV with the CMS detector at the LHC in 2011. The integrated luminosity of the sample is 4.98 inverse femtobarns. The observed number of events is found to be consistent with the standard model expectation, which is evaluated using control samples in the data. The results are used to constrain cross sections for the production of supersymmetric particles decaying to b-quark-enriched final states in the context of simplified model spectra.Comment: Submitted to Physical Review