719 research outputs found

    Effects of pleurotomy on the pulmonary mechanics and gas exchange after of pump coronary artery bypass grafting

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    OBJETIVO: Avaliar os efeitos da pleurotomia na mecânica pulmonar e trocas gasosas após cirurgia de revascularização do miocárdio (RM), utilizando enxerto de artéria torácica interna esquerda (ATIE), sem circulação extracorpórea (CEC). MÉTODO: Trinta e dois pacientes foram alocados prospectivamente em dois grupos: grupo PA (n=16 pacientes com abertura da cavidade pleural esquerda); grupo PI (n=16 pacientes com cavidade pleural intacta). Todos os pacientes foram submetidos às medidas de complacência pulmonar e resistência de vias aéreas durante a cirurgia de RM, antes da abertura do tórax e após o fechamento do tórax. Nestes momentos também foram avaliados os gases sanguíneos arteriais e o shunt pulmonar. RESULTADOS: Ambos os grupos obtiveram queda significante da complacência estática após o fechamento do tórax (p<0,0001) mas quando comparados entre si o grupo PA obteve queda significantemente maior (p=0,017). Houve queda da complacência dinâmica para ambos os grupos (p<0,0001), no entanto, entre os grupos não houve diferença significante (p=0,13). A resistência de vias aéreas aumentou em ambos os grupos (p<0,05), porém o grupo PA mostrou maior aumento (p=0,013). Houve decréscimo da PaO2 em ambos os grupos (p<0,0001) com maior queda para o grupo PA (p=0,046). O shunt pulmonar aumentou em ambos os grupos (p<0,0001), mas o grupo PA apresentou maior aumento (p=0,046). O tempo de intubação orotraqueal (p=0,041) e a permanência no hospital (p=0,0004) foram menores no grupo PI. CONCLUSÃO: A cirurgia de RM, utilizando enxerto de ATIE sem CEC, independente da abertura pleural induziu um significante prejuízo na mecânica pulmonar e trocas gasosas após fechamento do tórax. Entretanto os pacientes submetidos à pleurotomia demonstraram um decréscimo maior da complacência estática e aumento mais acentuado da resistência de vias aéreas e do shunt pulmonar quando comparado aos pacientes com pleura intacta.BACKGROUND: To evaluate the effects of pleurotomy on pulmonary mechanics and gas changes after off-pump coronary artery bypass (OPCAB) using left internal thoracic artery (LITA). METHODS: Thirty two patients were prospectively allocated in two groups: group OP (n=16 patients with opened left pleural cavity); group IP (n=16 patients with intact pleural cavity). All patients were submit for the measure of the pulmonary compliance and resistance of the lungs during the surgery, before the median sternotomy and after the chest closed. In this moment were analyzed the artery blood gas and pulmonary shunt. RESULTS: Both groups showed significantly decrease of static lung compliance after chest closed (p<0,0001) but when compared both groups the group OP had a decrease significantly major (p=0,017). There was decrease of dynamic lung compliance for both groups (p<0,0001), however, between the groups there was no significantly difference (p=0,13). The resistance of the lungs increased in both groups (p<0,05), however the group OP has a major increase (p=0,013). There was decreased of PaO2 for both groups ((p<0,0001) with more decrease for the group OP (p=0,046). The pulmonary shunt had a significantly increase for both groups (p<0,0001), when compared both of then the OP had major increase (p=0,046). Orotracheal intubation time (p=0.041) and hospital stay (p=0,0004) were shorter in group IP. CONCLUSION: OPCAB using LITA, independently of pleural opening, induced significant damage on pulmonary mechanics and gas changes after the chest closed. However the patients undergoing pleurotomy demonstrated a major decrease of static compliance and major increase of the resistance of the lungs and pulmonary shunt when compared patients whit intact pleural cavityBV UNIFESP: Teses e dissertaçõe

    Pleurotomy with subxyphoid pleural drain affords similar effects to pleural integrity in pulmonary function after off-pump coronary artery bypass graft

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    Background: Exacerbation of pulmonary dysfunction has been reported in patients receiving a pleural drain inserted through the intercostal space in comparison to patients with an intact pleura undergoing coronary artery bypass grafting (CABG). Evidence suggests that shifting the site of pleural drain insertion to the subxyphoid position minimizes chest wall trauma and preserves respiratory function in the early postoperative period. the aim of this study was to compare the pulmonary function parameters, clinical outcomes, and pain score between patients undergoing pleurotomy with pleural drain placed in the subxyphoid position and patients with intact pleural cavity after off-pump CABG (OPCAB) using left internal thoracic artery (LITA).Methods: Seventy-one patients were allocated into two groups: I (n = 38 open left pleural cavity and pleural drain inserted in the subxyphoid position); II (n = 33 intact pleural cavity). Pulmonary function tests and clinical parameters were recorded preoperatively and on postoperative days (POD) 1, 3 and 5. Arterial blood gas analysis and shunt fraction were evaluated preoperatively and in POD1. Pain score was assessed on POD1. To monitor pleural effusion and atelectasis chest radiography was performed routinely 1 day before operation and until POD5.Results: in both groups a significant impairment was found in lung function parameters until on POD5. However, no significant difference in forced vital capacity and forced expiratory volume in 1 second were seen between groups. A significant decrease in partial pressure of arterial oxygen and an increase in shunt fraction values were observed on POD1 in both groups, but no statistical difference was found when the groups were compared. Pleural effusion and atelectasis until on POD5 were similar in both groups. There were no statistical differences in pain score, duration of mechanical ventilation and postoperative hospital stay between groups.Conclusion: Subxyphoid insertion of pleural drain provides similar effects to preserved pleural integrity in pulmonary function, clinical outcomes, and thoracic pain after OPCAB. Therefore, our results support the hypothesis that once pleural cavities are incidentally or purposely opened during LITA dissection, subxyphoid placement of the pleural drain is recommended.Universidade Federal de São Paulo, Escola Paulista Med, Pirajussara Hosp, Dept Med,Cardiol Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Cardiol Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Physiotherapy Sch, Dept Human Movement Sci, BR-11060001 Santos, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Pneumol Discipline, BR-04039002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Pirajussara Hosp, Dept Med,Cardiovasc Surg Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Cardiovasc Surg Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Pirajussara Hosp, Dept Med,Cardiol Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Cardiol Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Physiotherapy Sch, Dept Human Movement Sci, BR-11060001 Santos, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Pneumol Discipline, BR-04039002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Pirajussara Hosp, Dept Med,Cardiovasc Surg Discipline, BR-04024002 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo Hosp, Dept Med,Cardiovasc Surg Discipline, BR-04024002 São Paulo, BrazilWeb of Scienc

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

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    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

    Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

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    Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

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    Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

    Measurement of the top quark mass using charged particles in pp collisions at root s=8 TeV

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    Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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    An embedding technique to determine ττ backgrounds in proton-proton collision data

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    An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

    Measurement of the Splitting Function in &ITpp &ITand Pb-Pb Collisions at root&ITsNN&IT=5.02 TeV

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    Data from heavy ion collisions suggest that the evolution of a parton shower is modified by interactions with the color charges in the dense partonic medium created in these collisions, but it is not known where in the shower evolution the modifications occur. The momentum ratio of the two leading partons, resolved as subjets, provides information about the parton shower evolution. This substructure observable, known as the splitting function, reflects the process of a parton splitting into two other partons and has been measured for jets with transverse momentum between 140 and 500 GeV, in pp and PbPb collisions at a center-of-mass energy of 5.02 TeV per nucleon pair. In central PbPb collisions, the splitting function indicates a more unbalanced momentum ratio, compared to peripheral PbPb and pp collisions.. The measurements are compared to various predictions from event generators and analytical calculations.Peer reviewe
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