126 research outputs found

    Isogeometric analysis for fluid shear stress in cancer cells

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    Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2018 do Instituto Politécnico de Lisboa. Código de referência IPL/2018/IGACFC_ISELThe microenvironment of the tumor is a key factor regulating tumor cell invasion and metastasis. The effects of physical factors in tumorigenesis is unclear. Shear stress, induced by liquid flow, plays a key role in proliferation, apoptosis, invasion, and metastasis of tumor cells. The mathematical models have the potential to elucidate the metastatic behavior of the cells’ membrane exposed to these microenvironment forces. Due to the shape configuration of the cancer cells, Non-uniform Rational B-splines (NURBS) lines are very adequate to define its geometric model. The Isogeometric Analysis allows a simplified transition of exact CAD models into the analysis avoiding the geometrical discontinuities of the traditional Galerkin traditional techniques. In this work, we use an isogeometric analysis to model the fluid-generated forces that tumor cells are exposed to in the vascular and tumor microenvironments, in the metastatic process. Using information provided by experimental tests in vitro, we present a suite of numerical experiments which indicate, for standard configurations, the metastatic behavior of cells exposed to such forces. The focus of this paper is strictly on geometrical sensitivities to the shear stress’ exhibition for the cell membrane, this being its innovation.info:eu-repo/semantics/publishedVersio

    Bloqueio Atrioventricular Total Associado a Hipertireoidismo por Doença de Graves

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    Descrevemos o caso de uma paciente jovem, portadora de hipertireoidismo por doença de Graves, que durante admissao hospitalar desenvolveu quadro grave de instabilidade hemodinâmica, evoluindo com bloqueio atrioventricular total (BAVT) e necessidade de marcapasso provisório. Após introduçao de droga antitireoidiana e uso de corticóide, houve recuperaçao do grau de bloqueio com 36 horas. Um possível mecanismo, no estado de hipertireoidismo, seria o efeito direto do hormônio tireoidiano no sistema de conduçao ou a infiltraçao linfocitária na regiao do sistema de conduçao cardíaco, considerando a natureza auto-imune da doença de base. Esses mecanismos sao discutidos por nós e por outros autores na literatura

    Bloqueio Atrioventricular Total Associado a Hipertireoidismo por Doença de Graves

    Get PDF
    Descrevemos o caso de uma paciente jovem, portadora de hipertireoidismo por doença de Graves, que durante admissao hospitalar desenvolveu quadro grave de instabilidade hemodinâmica, evoluindo com bloqueio atrioventricular total (BAVT) e necessidade de marcapasso provisório. Após introduçao de droga antitireoidiana e uso de corticóide, houve recuperaçao do grau de bloqueio com 36 horas. Um possível mecanismo, no estado de hipertireoidismo, seria o efeito direto do hormônio tireoidiano no sistema de conduçao ou a infiltraçao linfocitária na regiao do sistema de conduçao cardíaco, considerando a natureza auto-imune da doença de base. Esses mecanismos sao discutidos por nós e por outros autores na literatura

    Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

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    Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson

    Standalone vertex finding in the ATLAS muon spectrometer

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    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

    Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of √s=7 TeV proton-proton collisions

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    Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

    Thalidomide plus dexamethasone as a maintenance therapy after autologous hematopoietic stem cell transplantation improves progression-free survival in multiple myeloma

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    Despite the good response of stem cell transplant (SCT) in the treatment of multiple myeloma (MM), most patients relapse or do not achieve complete remission, suggesting that additional treatment is needed. We assessed the impact of thalidomide in maintenance after SCT in untreated patients with MM. A hundred and eight patients (<70 years old) were randomized to receive maintenance with dexamethasone (arm A; n = 52) or dexamethasone with thalidomide (arm B; n = 56; 200 mg daily) for 12 months or until disease progression. After a median follow-up of 27 months, an intention to treat analysis showed a 2-year progression-free survival (PFS) of 30% in arm A (95% CI 2238) and 64% in arm B (95% CI 5771; P = 0.002), with median PFS of 19 months and 36 months, respectively. In patients who did not achieve at least a very good partial response, the PFS at 2 years was significantly higher when in use of thalidomide (19 vs. 59%; P = 0.002). Overall survival at 2 years was not significantly improved (70 vs. 85% in arm A and arm B, respectively; P = 0.27). The addition of thalidomide to dexamethasone as maintenance improved the PFS mainly in patients who did not respond to treatment after SCT. Am. J. Hematol. (c) 2012 Wiley Periodicals, Inc.FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)CNPq (Conselho Nacional do Desenvolvimento Cientifico e Tecnologico)Conselho Nacional do Desenvolvimento Cientifico e Tecnologico (CNPq)FAPERJ (Fundacao de Apoio a Pesquisa do Estado do Rio de Janeiro)FAPERJ (Fundacao de Apoio a Pesquisa do Estado do Rio de Janeiro

    Search for dark matter in events with a hadronically decaying W or Z boson and missing transverse momentum in pp collisions at s√= 8 TeV with the ATLAS detector

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    A search is presented for dark matter pair production in association with a W or Z boson in pp collisions representing 20.3  fb−1 of integrated luminosity at s√=8  TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet with the jet mass consistent with a W or Z boson, and with large missing transverse momentum are analyzed. The data are consistent with the standard model expectations. Limits are set on the mass scale in effective field theories that describe the interaction of dark matter and standard model particles, and on the cross section of Higgs production and decay to invisible particles. In addition, cross section limits on the anomalous production of W or Z bosons with large missing transverse momentum are set in two fiducial regions.We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC, and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST, and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR, and VSC CR, Czech Republic; DNRF, DNSRC, and Lundbeck Foundation, Denmark; EPLANET, ERC, and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG, and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, DIP, and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW and NCN, Poland; GRICES and FCT, Portugal; MNE/IFA, Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MIZS, Slovenia; DST/NRF, South Africa; MINECO, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF, and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society, and Leverhulme Trust, United Kingdom; U.S. DOE and NSF, United States of America. The crucial computing support from all WLCG partners is acknowledged gratefully, in particular from CERN and the ATLAS Tier-1 facilities at TRIUMF (Canada), NDGF (Denmark, Norway, Sweden), CC-IN2P3 (France), KIT/GridKA (Germany), INFN-CNAF (Italy), NL-T1 (Netherlands), PIC (Spain), ASGC (Taiwan), RAL (UK), and BNL (U.S.), and in the Tier-2 facilities worldwide

    Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector

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    This paper presents a measurement of the top quark pair ( tt¯ ) production charge asymmetry A C using 4.7 fb−1 of proton-proton collisions at a centre-of-mass energy √s = 7 TeV collected by the ATLAS detector at the LHC. A tt¯ -enriched sample of events with a single lepton (electron or muon), missing transverse momentum and at least four high transverse momentum jets, of which at least one is tagged as coming from a b-quark, is selected. A likelihood fit is used to reconstruct the tt¯ event kinematics. A Bayesian unfolding procedure is employed to estimate A C at the parton-level. The measured value of the tt¯ production charge asymmetry is A C = 0.006 ± 0.010, where the uncertainty includes both the statistical and the systematic components. Differential A C measurements as a function of the invariant mass, the rapidity and the transverse momentum of the tt¯ system are also presented. In addition, A C is measured for a subset of events with large tt¯ velocity, where physics beyond the Standard Model could contribute. All measurements are consistent with the Standard Model predictions

    Search for direct third-generation squark pair production in final states with missing transverse momentum and two b-jets in √s=8 TeV pp collisions with the ATLAS detector

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    The results of a search for pair production of supersymmetric partners of the Standard Model third-generation quarks are reported. This search uses 20.1 fb−1 of pp collisions ats√=8TeV collected by the ATLAS experiment at the Large Hadron Collider. The lightest bottom and top squarks (b˜1andt˜1respectively) are searched for in a final state with large missing transverse momentum and two jets identified as originating from b-quarks. No excess of events above the expected level of Standard Model background is found. The results are used to set upper limits on the visible cross section for processes beyond the Standard Model. Exclusion limits at the 95 % confidence level on the masses of the third-generation squarks are derived in phenomenological supersymmetric R-parity-conserving models in which either the bottom or the top squark is the lightest squark. Theb˜1is assumed to decay viab˜1→b∼0χ1and thet˜1viat˜1→b∼±χ1, with undetectable products of the subsequent decay of the∼±χ1due to the small mass splitting between the∼±χ1and the∼0χ1
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