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We study the axial U(1) symmetry at a finite temperature in two-flavor lattice QCD. Employing the Mobius domain-wall fermions, we generate gauge configurations slightly above the critical temperature Tc with different lattice sizes L = 2-4 fm. Our action allows frequent topology tunneling while keeping good chiral symmetry close enough to that of overlap fermions. This allows us to recover full chiral symmetry by an overlap/domain-wall reweighting. Above the phase transition, a strong suppression of the low-lying modes is observed in both overlap and domain-wall Dirac spectra. We, however, find a sizable violation of the Ginsparg-Wilson relation in the Mobius domain-wall Dirac eigenmodes, which dominates the signals of the axial U(1) symmetry breaking near the chiral limit. We also find that the use of the overlap fermion only in the valence sector is dangerous since it suffers from the artifacts due to partial quenching. Reweighting the Mobius domain-wall fermion determinant to that of the overlap fermion, we observe the axial U(1) breaking to vanish in the chiral limit, which is stable against the changes of the lattice volume and lattice spacing.

We calculate the form factors of the K→πlν semileptonic decays in three-flavor lattice QCD and study their chiral behavior as a function of the momentum transfer and the Nambu-Goldstone boson masses. Chiral symmetry is exactly preserved by using the overlap quark action, which enables us to directly compare the lattice data with chiral perturbation theory (ChPT). We generate gauge ensembles at a lattice spacing of 0.11 fm with four pion masses covering 290–540 MeV and a strange quark mass ms close to its physical value. By using the all-to-all quark propagator, we calculate the vector and scalar form factors with high precision. Their dependence on ms and the momentum transfer is studied by using the reweighting technique and the twisted boundary conditions for the quark fields. We compare the results for the semileptonic form factors with ChPT at next-to-next-to-leading order in detail. While many low-energy constants appear at this order, we make use of our data of the light meson electromagnetic form factors in order to control the chiral extrapolation. We determine the normalization of the form factors as f+(0)=0.9636(36)(+57−35) and observe reasonable agreement of their shape with experiment.

We calculate the form factors of the $K \to ��l ��$ semileptonic decays in three-flavor lattice QCD, and study their chiral behavior as a function of the momentum transfer and the Nambu-Goldstone boson masses. Chiral symmetry is exactly preserved by using the overlap quark action, which enables us to directly compare the lattice data with chiral perturbation theory (ChPT). We generate gauge ensembles at a lattice spacing of 0.11fm with four pion masses covering 290-540 MeV and a strange quark mass m_s close to its physical value. By using the all-to-all quark propagator, we calculate the vector and scalar form factors with high precision. Their dependence on m_s and the momentum transfer is studied by using the reweighting technique and the twisted boundary conditions for the quark fields. We compare the results for the semileptonic form factors with ChPT at next-to-next-to leading order in detail. While many low-energy constants appear at this order, we make use of our data of the light meson electromagnetic form factors in order to control the chiral extrapolation. We determine the normalization of the form factors as f_+(0) = 0.9636(36)(+57/-35), and observe reasonable agreement of their shape with experiment., 34 pages, 13 figures

We study the chiral behavior of the electromagnetic (EM) form factors of pion and kaon in three-flavor lattice QCD. In order to make a direct comparison of the lattice data with chiral perturbation theory (ChPT), we employ the overlap quark action that has exact chiral symmetry. Gauge ensembles are generated at a lattice spacing of 0.11 fm with four pion masses ranging between M_pi \simeq 290 MeV and 540 MeV and with a strange quark mass m_s close to its physical value. We utilize the all-to-all quark propagator technique to calculate the EM form factors with high precision. Their dependence on m_s and on the momentum transfer is studied by using the reweighting technique and the twisted boundary conditions for the quark fields, respectively. A detailed comparison with SU(2) and SU(3) ChPT reveals that the next-to-next-to-leading order terms in the chiral expansion are important to describe the chiral behavior of the form factors in the pion mass range studied in this work. We estimate the relevant low-energy constants and the charge radii, and find reasonable agreement with phenomenological and experimental results., 59 pages, 34 figures

L'objectif de ce travail est d'évaluer si la mesure de la pression intracrânienne (PIC), à l'aide d'un capteur intraparenchymateux ou intraventriculaire, est prédictive d'un pronostic fonctionnel ou d'un risque de mortalité plus important chez les patients victimes d'une hémorragie sous-arachnoïdienne post rupture anévrismale (HSAa). Dans la prise en charge aigue de ces patients aux unités de soins intensifs, le neuromonitoring avec la mise en place d'un capteur intraparenchymateux ou intraventriculaire pour la mesure de la PIC n'est pas standardisé et la décision de neuro monitorer ces patients dépend du praticien et des centres. Pour essayer à répondre à cette question de l'utilité de ce neuromonitoring, on a réalisé une revue systématique de la littérature en utilisant les bases de donnés PubMed, Cochrane et ClinicalTrials.gov en accord avec les critères PRISMA. Nos critères d'inclusion sont les études ayant inclus des patients adultes avec HSAa et qui ont bénéficié d'une mesure de PIC par capteur intraparenchymateux ou intraventriculaire. On a évalué le pronostic fonctionnel, les complications ischémiques au niveau cérébral et la mortalité associée à l'HSA selon les valeurs de la PIC. On a exclu toutes les études incluant une population pédiatrique ou sans monitorage de la PIC par les méthodes citées. La qualité des évidences de nos différentes conclusions a été évaluée selon le système GRADE. Vingt-six articles ont été inclus. Une corrélation a été démontrée entre les valeurs de PIC élevées et le taux de mortalité après HSAa. Toutefois les valeurs absolues de la PIC ne sont pas des valeurs prédictives indépendantes du pronostic fonctionnel à long terme (qualité d'évidence basse). Une relation faible a été trouvée entre les valeurs de PIC et les complications ischémiques cérébrales par vasospasme (qualité d'évidence très basse). Les valeurs dérivées de la PIC ont une valeur supérieure que les valeurs absolues de la PIC dans la prédiction de la récupération fonctionnelle (qualité d'évidence modérée). En raison de l'absence de conclusions de haute qualité d'évidence définissant la relation entre la PIC et le pronostic fonctionnel des patients avec HSAa, des études ultérieures prospectives et randomisées sont nécessaire pour démontrer l'intérêt du monitorage de la pression intracrânienne et ses implications cliniques.

The flavor-singlet component of the η′ meson is related to the topological structure of the SU(3) gauge field through the chiral anomaly. We perform a 2+1-flavor lattice QCD calculation and demonstrate that the two-point function of a gluonically defined topological charge density after a short Yang-Mills gradient flow contains the propagation of the η′ meson, by showing that its mass in the chiral and continuum limit is consistent with the experimental value. The gluonic correlator does not suffer from the contamination of the pion contribution, and the clean signal is obtained at significantly lower numerical cost compared to the conventional method with the quark bilinear operators.

Summary Background Mutations in LRRK2 , the gene that encodes leucine-rich repeat kinase 2, are a cause of Parkinson's disease (PD). The International LRRK2 Consortium was established to answer three key clinical questions: can LRRK2 -associated PD be distinguished from idiopathic PD; which mutations in LRRK2 are pathogenic; and what is the age-specific cumulative risk of PD for individuals who inherit or are at risk of inheriting a deleterious mutation in LRRK2 ? Methods Researchers from 21 centres across the world collaborated on this study. The frequency of the common LRRK2 Gly2019Ser mutation was estimated on the basis of data from 24 populations worldwide, and the penetrance of the mutation was defined in 1045 people with mutations in LRRK2 from 133 families. The LRRK2 phenotype was defined on the basis of 59 motor and non-motor symptoms in 356 patients with LRRK2 -associated PD and compared with the symptoms of 543 patients with pathologically proven idiopathic PD. Findings Six mutations met the consortium's criteria for being proven pathogenic. The frequency of the common LRRK2 Gly2019Ser mutation was 1% of patients with sporadic PD and 4% of patients with hereditary PD; the frequency was highest in the middle east and higher in southern Europe than in northern Europe. The risk of PD for a person who inherits the LRRK2 Gly2019Ser mutation was 28% at age 59 years, 51% at 69 years, and 74% at 79 years. The motor symptoms (eg, disease severity, rate of progression, occurrence of falls, and dyskinesia) and non-motor symptoms (eg, cognition and olfaction) of LRRK2 -associated PD were more benign than those of idiopathic PD. Interpretation Mutations in LRRK2 are a clinically relevant cause of PD that merit testing in patients with hereditary PD and in subgroups of patients with PD. However, this knowledge should be applied with caution in the diagnosis and counselling of patients. Funding UK Medical Research Council; UK Parkinson's Disease Society; UK Brain Research Trust; Internationaal Parkinson Fonds; Volkswagen Foundation; National Institutes of Health: National Institute of Neurological Disorders and Stroke and National Institute of Aging; Udall Parkinson's Disease Centre of Excellence; Pacific Alzheimer Research Foundation Centre; Italian Telethon Foundation; Fondazione Grigioni per il Morbo di Parkinson; Michael J Fox Foundation for Parkinson's Research; Safra Global Genetics Consortium; US Department of Veterans Affairs; French Agence Nationale de la Recherche.

The Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) has been available in English since 2008. As part of this process, the MDS-UPDRS organizing team developed guidelines for development of official non- English translations. We present here the formal process for completing officially approved non-English versions of the MDS-UPDRS and specifically focus on the first of these versions in Italian. The MDS-UPDRS was translated into Italian and tested in 377 native-Italian speaking PD patients. Confirmatory and exploratory factor analyses determined whether the factor structure for the English- language MDS-UPDRS could be confirmed in data col- lected using the Italian translation. To be designated an 'Official MDS translation,' the Comparative Fit Index (CFI) had to be C0.90 relative to the English-language version. For all four parts of the Italian MDS-UPDRS, the CFI, in comparison with the English-language data, was C0.94. Exploratory factor analyses revealed some differ- ences between the two datasets, however these differences were considered to be within an acceptable range. The Italian version of the MDS-UPDRS reaches the criterion to be designated as an Official Translation and is now avail- able for use. This protocol will serve as outline for further validation of this in multiple languages.