47 research outputs found
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Efficacy and safety of a VWF/FVIII concentrate (wilate®) in inherited von Willebrand disease patients undergoing surgical procedures
Introduction: Surgical procedures in von Willebrand disease (VWD) patients may require prophylactic treatment with exogenous von Willebrand factor (VWF) and coagulation factor VIII (FVIII) to prevent excessive bleeding. Wilate\uc2\uaeis a plasma-derived, double virus-inactivated, highly purified, freeze-dried VWF/FVIII concentrate, containing both factors in a physiological activity ratio of 1:1. Aim: To investigate the efficacy and safety of wilate\uc2\uaein maintaining haemostasis in VWD patients undergoing surgical procedures. Methods: This prospective, open-label multinational clinical study documents 28 individuals who underwent 30 surgical procedures managed with wilate\uc2\uae. Twenty-one patients had VWD Type 3, and 21 surgeries were major. Efficacy was assessed intra- and postoperatively by the surgeon and investigator, respectively, and adjudicated by an Independent Data Monitoring Committee, using an objective scale based on blood loss, transfusion requirements and postoperative bleeding and oozing. Treatment success (primary endpoint) was determined using a composite assessment algorithm and was formally assessed. Results: Surgical prophylaxis with wilate\uc2\uaewas successful in 29 of 30 procedures. The overall rate of success was 96.7% (98.75% CI: 0.784, 1.000). All 21 surgeries in patients with VWD Type 3 were managed successfully. There was no accumulation of VWF or FVIII after multiple dosing, and no thromboembolic events or inhibitors to VWF or FVIII were observed. Conclusions: Wilate\uc2\uaedemonstrated effective prevention and treatment of bleeding in inherited VWD patients undergoing surgery, with no clinically significant safety concerns
Studies of jet quenching using isolated-photon + jet correlations in PbPb and pp collisions at sqrt(s[NN]) = 2.76 TeV
Results from the first study of isolated-photon + jet correlations in
relativistic heavy ion collisions are reported. The analysis uses data from
PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair
corresponding to an integrated luminosity of 150 inverse microbarns recorded by
the CMS experiment at the LHC. For events containing an isolated photon with
transverse momentum pt(gamma) > 60 GeV and an associated jet with pt(Jet) > 30
GeV, the photon + jet pt imbalance is studied as a function of collision
centrality and compared to pp data and PYTHIA calculations at the same
collision energy. Using the pt(gamma) of the isolated photon as an estimate of
the momentum of the associated parton at production, this measurement allows an
unbiased characterisation of the in-medium parton energy loss. For more central
PbPb collisions, a significant decrease in the ratio pt(Jet)/pt(gamma) relative
to that in the PYTHIA reference is observed. Furthermore, significantly more
pt(gamma) > 60 GeV photons in PbPb are observed not to have an associated
pt(Jet) > 30 GeV jet, compared to the reference. However, no significant
broadening of the photon + jet azimuthal correlation is observed.Comment: Submitted to Physics Letters
Regulation of intracellular free arachidonic acid in Aplysia nervous system
We have studied the regulation of arachidonic acid (AA) uptake, metabolism, and release in Aplysia nervous system. Following uptake of [ 3 H]AA, the distribution of radioactivity in intracellular and extracellular lipid pools was measured as a function of time in the presence or absence of exogenous AA. The greatest amount of AA was esterified into phosphatidylinositol (relative to pool size). We found that the intracellular free AA pool underwent rapid turnover, and that radioactive free AA and eicosanoids were released at a rapid rate into the extracellular medium, both in the presence and absence of exogenous AA. Most of the released radioactivity originated from phosphatidylinositol.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48020/1/232_2005_Article_BF01868464.pd
Measurement of forward charged hadron flow harmonics in peripheral PbPb collisions at √sNN = 5.02 TeV with the LHCb detector
Flow harmonic coefficients,
v
n
, which are the key to studying the hydrodynamics of the quark-gluon plasma (QGP) created in heavy-ion collisions, have been measured in various collision systems and kinematic regions and using various particle species. The study of flow harmonics in a wide pseudorapidity range is particularly valuable to understand the temperature dependence of the shear viscosity to entropy density ratio of the QGP. This paper presents the first LHCb results of the second- and the third-order flow harmonic coefficients of charged hadrons as a function of transverse momentum in the forward region, corresponding to pseudorapidities between 2.0 and 4.9, using the data collected from PbPb collisions in 2018 at a center-of-mass energy of 5.02
TeV
. The coefficients measured using the two-particle angular correlation analysis method are smaller than the central-pseudorapidity measurements at ALICE and ATLAS from the same collision system but share similar features
Helium identification with LHCb
The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei
Curvature-bias corrections using a pseudomass method
Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass
Repressor activity of CCAAT displacement protein in HL-60 myeloid leukemia cells.
CCAAT displacement protein (CDP)/cut is implicated in several systems as a transcriptional repressor of developmentally regulated genes. In myeloid leukemia cells, CDP/cut binding activity as assayed on the promoter of the phagocyte-specific cytochrome heavy chain gene gp91-phox varies inversely with expression of gp91-phox mRNA. We used two approaches to ascertain whether CDP/cut serves as a repressor of gp91-phox gene expression. First, we used transient transfection assays in 3T3 cells to demonstrate that the CDP/cut binding site from the gp91-phox promoter acts as a negative regulatory element in artificial promoter constructs. Second, we isolated a stable transformant of HL-60 myeloid cells constitutively expressing transfected CDP/cut cDNA. Stable transformants carrying expression vector alone or expressing CDP/cut mRNA were induced to differentiate along the macrophage lineage with phorbol ester or along the neutrophil lineage with dimethyl sulfoxide or retinoic acid/dimethylformamide. Northern blot analysis was used to assess induction of mRNAs encoding gp91-phox, and the myeloid oxidase cytosolic components, p47 and p67. In the stable transformant expressing transfected CDP/cut cDNA, gp91-phox induction was selectively reduced, whereas morphologic differentiation and induction of mRNA for myeloid oxidase components p47 and p67 were unaffected. These data provide persuasive evidence that CDP/cut acts to repress the gp91-phox gene
Valorização da biomassa lenhocelulósica: estudo de sacarificação enzimática do cardo e da esteva
Dissertação de mestrado em Engenharia do ambiente. Instituto Politécnico de Beja, Escola Superior Agrária, 2013.A Cynara cardunculus e o Cistus ladanifer, são duas espécies bem adaptadas às
condições edafoclimáticas do Alentejo, e uma alternativa aos materiais fósseis no
contexto de biorrefinaria, visto serem biomassas lenhocelulósicas. No presente trabalho
desenvolveu-se um estudo com a finalidade de utilizar as duas biomassas e perceber
como se comportam na sacarificação enzimática da celulose, que efeitos têm os prétratamentos
na eficiência da mesma e que efeito tem o recipiente onde se realiza a
hidrólise. Foi ainda elaborado um desenho experimental com o cardo, com o objetivo de
otimizar a sacarificação enzimática quanto à quantidade de sólidos, e enzimas a usar.
Os resultados mostram que o cardo é mais sacarificável que a esteva e que os prétratamentos
aumentaram a acessibilidade das enzimas, para a fração celulósica
relativamente ao material não tratado. Para ambas as biomassas o pré-tratamento mais
eficaz foi a explosão de vapor lavado com NaOH, tendo-se produzido 27,8 e 20,9 g/L de
glucose para o cardo e esteva, respetivamente.
A sacarificação da biomassa nos tubos “falcon”, foi menor do que nos tubos centrífuga e
Erlenmeyer, que não apresentaram diferenças significativas. O valor máximo previsto
para o CHA 130 pelo desenho experimental é de 31,7±1,0 g/L para CS=8, FPU=44,6,
CBU=51,9