The controversy about "1/m_Q duality violation" ; a quark model point of view

A detailed discussion based on exact calculations, possible in the non relativistic quark model, is given to show that there is no 1/m_Q term in the heavy quark expansion of totally integrated semileptonic decay rates. More generally, it is shown that OPE holds with very few terms in the expansion, at least in the harmonic oscillator model.Comment: 10 pages, full articl

Automated Code Generation for Lattice Quantum Chromodynamics and beyond

We present here our ongoing work on a Domain Specific Language which aims to simplify Monte-Carlo simulations and measurements in the domain of Lattice Quantum Chromodynamics. The tool-chain, called Qiral, is used to produce high-performance OpenMP C code from LaTeX sources. We discuss conceptual issues and details of implementation and optimization. The comparison of the performance of the generated code to the well-established simulation software is also made

The implementation of the WTO Agreement on the Application of Sanitary and Phytosanitary Measures: reflections in France

The Agreement on the Application of Sanitary and Phytosanitary measures (SPS Agreement) establishes a new legal framework for the Members of the World Trade Organization regarding restrictions on trade for sanitary or phytosanitary reasons. Some positive effects are beyond question, among which a greater transparency for requirements for gaining access to markets and an efficient control of practices at importation. Despite several limits, the SPS Agreement is so well balanced that, up to now, the WTO Members have not wished to renegociate it.L'Accord sur l'application des mesures sanitaires et phytosanitaires (Accord SPS) instaure un cadre juridique nouveau pour les membres de l'Organisation mondiale du commerce (OMC), en matière de restrictions aux échanges commerciaux internationaux pour des motifs sanitaires ou phytosanitaires. Il peut être crédité d'effets positifs indéniables parmi lesquels une plus grande transparence des conditions d'accès au marché et l'encadrement des pratiques à l'importation. Malgré certaines limites, l'Accord SPS se révèle suffisamment équilibré pour que les Membres de l'OMC n'aient pas souhaité à ce jour le renégocier

Testing OPE for ghosts, gluons and αs\alpha_s

We present here our results on extracting Wilson coefficients from different quantities such as ghost and gluon propagators which are calculated by means of Lattice QCD. The results confirm the validity of our method for the calculation of the strong coupling constant as well as allow to estimate the range of momenta where OPE is applicable.Comment: arXiv admin note: substantial text overlap with arXiv:1301.759

PetaQCD : En Route for the automatic code generation for lattice QCD

International audienceNew computer architectures with various weak and strong characteristics appear with increasing speed. We present our work in progress for the tool-chain aimed at rapid prototyping of the novel dirac matrix inversion algorithms for emerging architectures. From scientific description of the algorithm on the front end to the several back ends we discuss how symbolic manipulation may be used to create and optimize lattice calculations on the fly

Risk factors for post-ICU red blood cell transfusion: a prospective study

INTRODUCTION: Factors predictive of the need for red blood cell (RBC) transfusion in the intensive care unit (ICU) have been identified, but risk factors for transfusion after ICU discharge are unknown. This study aims identifies risk factors for RBC transfusion after discharge from the ICU. METHODS: A prospective, monocentric observational study was conducted over a 6-month period in a 24-bed medical ICU in a French university hospital. Between June and December 2003, 550 critically ill patients were consecutively enrolled in the study. RESULTS: A total of 428 patients survived after treatment in the ICU; 47 (11% of the survivors, 8.5% of the whole population) required RBC transfusion within 7 days after ICU discharge. Admission for sepsis (odds ratio [OR] 341.60, 95% confidence interval [CI] 20.35–5734.51), presence of an underlying malignancy (OR 32.6, 95%CI 3.8–280.1), female sex (OR 5.4, 95% CI 1.2–24.9), Logistic Organ Dysfunction score at ICU discharge (OR 1.45, 95% CI 1.1–1.9) and age (OR 1.06, 95% CI 1.02–1.12) were independently associated with RBC transfusion after ICU stay. Haemoglobin level at discharge predicted the need for delayed RBC transfusion. Use of vasopressors (OR 0.01, 95%CI 0.001–0.17) and haemoglobin level at discharge from the ICU (OR 0.02, 95% CI 0.007–0.09; P < 0.001) were strong independent predictors of transfusion of RBC 1 week after ICU discharge. CONCLUSION: Sepsis, underlying conditions, unresolved organ failures and haemoglobin level at discharge were related to an increased risk for RBC transfusion after ICU stay. We suggest that strategies to prevent transfusion should focus on homogeneous subgroups of patients and take into account post-ICU needs for RBC transfusion

CpG-ODN and MPLA Prevent Mortality in a Murine Model of Post-Hemorrhage-Staphyloccocus aureus Pneumonia

Infections are the most frequent cause of complications in trauma patients. Post-traumatic immune suppression (IS) exposes patients to pneumonia (PN). The main pathogen involved in PN is Methicillin Susceptible Staphylococcus aureus (MSSA). Dendritic cells () may be centrally involved in the IS. We assessed the consequences of hemorrhage on pneumonia outcomes and investigated its consequences on DCs functions. A murine model of hemorrhagic shock with a subsequent MSSA pneumonia was used. Hemorrhage decreased the survival rate of infected mice, increased systemic dissemination of sepsis and worsened inflammatory lung lesions. The mRNA expression of Tumor Necrosis Factor-alpha (TNF-α), Interferon-beta (IFN-β) and Interleukin (IL)-12p40 were mitigated for hemorrhaged-mice. The effects of hemorrhage on subsequent PN were apparent on the pDCs phenotype (reduced MHC class II, CD80, and CD86 molecule membrane expression). In addition, hemorrhage dramatically decreased CD8+ cDCs- and CD8- cDCs-induced allogeneic T-cell proliferation during PN compared with mice that did not undergo hemorrhage. In conclusion, hemorrhage increased morbidity and mortality associated with PN; induced severe phenotypic disturbances of the pDCs subset and functional alterations of the cDCs subset. After hemorrhage, a preventive treatment with CpG-ODN or Monophosphoryl Lipid A increased transcriptional activity in DCs (TNF-α, IFN-β and IL-12p40) and decreased mortality of post-hemorrhage MSSA pneumonia

Phénoménologie des mésons B et chromodynamique quantique sur réseau

Quelques aspects de la physique des mésons B ont été étudiés par lasimulation numérique de la Chromodynamique Quantique sur réseau, qui est une approche non perturbative - basée sur les principes premiers de la Théorie Quantique des Champs - de calculer les fonctions de Green de la théorie. Les couplages \hat{g} et \tilde{g} paramétrant le Lagrangien chiral effectif qui décrit les interactions entre mésons lourd-légers et pions mous ont été calculés au-delà de l'approximation quenched (à N_f=2). L'opérateur\bar{q}\gamma_\m \gc q a été renormalisé non perturbativement en utilisant les identités de Ward chirales. On trouve \hat{g}=0.4\div 0.6 et \tilde{g}=-0.1\div-0.3. La masse du quark étrange a été estimée parune simulation unquenched (à N_f=2): elle a été renormaliséedans le schéma non perturbatif RI-MOM. On obtient en faisant le raccordement avec le schéma MSbar m_s^{MSbar}(2 GeV)=101\pm 8^{+25}_{-0} MeV. Une méthode a été proposée pour évaluer sur le réseau les facteurs deforme associés aux transitions semileptoniques à recul nul B \to D^{**} décrites dans le cadre de la Théorie Effective des Quarks Lourds. La constante de renormalisation de l'opérateur \bar{h}\gamma_i \gc D_j h a été calculée à l'ordre d'une boucle de la théorie des perturbations.On trouve \tau_1/2(1)=0.3\div 0.5 et \tau_3/2(1)=0.5\div 0.7. Enfin le paramètre de sac associé à l'amplitude de mélange B_s-anti B_s a été évalué, en choisissant une action pour le quark étrange qui vérifie la symétrie chirale à maille a du réseau finie. De cette manière les erreurs systématiques, provenant des mélanges de chiralité, sont nettement réduites lors de la renormalisation de l'opérateur à 4 fermions \bar{h}\gamma_{\m L}q\bar{h}\gamma_{\m L}q. On obtient dans l'approximation quenched B_{B_s}=0.92(3).We have studied some phenomenological aspects of the B meson physics by using lattice QCD, which is a non perturbative method (based on the first principles of Quantum Field Theory) of computing Green functions of the theory. Pionic couplings \hat{g} and \tilde{g}, parameterizing the effective chiral Lagrangian which describes interactions between heavy-light mesons and soft pions, have been computed beyond the quenched approximation (at {\rm N_f}=2). We have renormalised the operator \bar{q}\gamma_\mu \gamma^5 q non perturbatively by using chiral Ward identities. We obtain \hat{g}=0.4\div0.6 and \tilde{g}=-0.1 \div -0.3. We have estimated from an unquenched simulation (at {\rm N_f}=2) the strange quark mass: the non perturbative renormalisation scheme RI-MOM has been applied. After the matching in the \msb scheme the result is m_s^{\msb}(2\,\gev)=101\pm 8^{+25}_{-0}~\mev. We have proposed a method to calculate on the lattice the Heavy Quark Effective Theory form factors of the semileptonic transitions B\to D^{**} at zero recoil. The renormalisation constant of the operator \bar{h}\gamma_i \gamma^5 D_j h has been computed at one-loop order of the perturbation theory. We obtain \taud (1)=0.3\div 0.5 and \taut(1)=0.5\div 0.7. Eventually the bag parameter B_{B_s} associated the B_s-\bsb mixing amplitude in the StandardModel has been estimated in the quenched approximation by using for the strange quark an action which verifies the chiral symmetry at finite lattice spacing a. Thus systematic errors are significantly reduced in the renormalisation procedure because the spurious mixing of the four-fermion operator \bar{h}\gamma_{\mu L} q \bar{h} \gamma_{\mu L} q with four-fermion operators of different chirality is absent. The result is B_{B_s}=0.92(3).ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF