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A bstract We determine the masses, the singlet and octet decay constants as well as the anomalous matrix elements of the η and η′ mesons in N f = 2 + 1 QCD. The results are obtained using twenty-one CLS ensembles of non-perturbatively improved Wilson fermions that span four lattice spacings ranging from a ≈ 0 . 086 fm down to a ≈ 0 . 050 fm. The pion masses vary from M π = 420 MeV to 126 MeV and the spatial lattice extents L s are such that L s M π ≳ 4, avoiding significant finite volume effects. The quark mass dependence of the data is tightly constrained by employing two trajectories in the quark mass plane, enabling a thorough investigation of U(3) large- N c chiral perturbation theory (ChPT). The continuum limit extrapolated data turn out to be reasonably well described by the next-to-leading order ChPT parametrization and the respective low energy constants are determined. The data are shown to be consistent with the singlet axial Ward identity and, for the first time, also the matrix elements with the topological charge density are computed. We also derive the corresponding next-to-leading order large- N c ChPT formulae. We find F 8 = 115 . 0(2 . 8) MeV, θ 8 = − 25 . 8(2 . 3)°, θ 0 = − 8 . 1(1 . 8)° and, in the MS ¯ scheme for N f = 3, F 0 ( μ = 2 GeV) = 100 . 1(3 . 0) MeV, where the decay constants read F η 8 = F 8 cos θ 8 , F η ′ 8 = F 8 sin θ 8 , F η 0 = −F 0 sin θ 0 and F η ′ 0 = F 0 cos θ 0 . For the gluonic matrix elements, we obtain a η ( μ = 2 GeV) = 0 . 0170(10) GeV 3 and a η′ ( μ = 2 GeV) = 0 . 0381(84) GeV 3 , where statistical and all systematic errors are added in quadrature.

We report recent efforts by CLS to generate an ensemble with physical lightand strange-quark masses in a lattice volume of 192 × 96 3 at β = 3:55 corresponding to a lattice spacing of 0:064 fm. This ensemble is being generated as part of the CLS 2+1 flavor effort with improved Wilson fermions. Our simulations currently cover 5 lattice spacings ranging from 0:039 fm to 0:086 fm at various pion masses along chiral trajectories with either the sum of the quark masses kept fixed, or with the strange-quark mass at the physical value. The current status of simulations is briefly reviewed, including a short discussion of measured autocorrelation times and of the main features of the simulations. We then proceed to discuss the thermalization strategy employed for the generation of the physical quark-mass ensemble and present first results for some simple observables. Challenges encountered in the simulation are highlighted.

We present preliminary results for the masses and decay constants of the η and η′ mesons using CLS N f = 2 + 1 ensembles. One of the major challenges in these calculations are the large statistical fluctuations due to disconnected quark loops. We tackle these by employing a combination of noise reduction techniques which are tuned to minimize the statistical error at a fixed cost. On the analysis side we carefully assess excited states contributions by using a direct fit approach.

A bstract We determine the light baryon spectrum on ensembles generated by the Coordinated Lattice Simulations (CLS) effort, employing N f = 2 + 1 flavours of non-perturbatively improved Wilson fermions. The hadron masses are interpolated and extrapolated within the quark mass plane, utilizing three distinct trajectories, two of which intersect close to the physical quark mass point and the third one approaching the SU(3) chiral limit. The results are extrapolated to the continuum limit, utilizing six different lattice spacings ranging from a ≈ 0 . 10 fm down to below 0.04 fm. The light pion mass varies from M π ≈ 429 MeV down to 127 MeV. In general, the spatial extent is kept larger than four times the inverse pion mass and larger than 2 . 3 fm, with additional small and large volume ensembles to investigate finite size effects. We determine the Wilson flow scales t 0 , ph = 0.1449 9 7 fm [ 1 ] and t 0 ∗ ≈ t 0 , ph [ 2 ] from the octet cascade (Ξ baryon). Determining the light baryon spectrum in the continuum limit, we find the nucleon mass m N = 941.7 7.6 6.5 MeV and the other stable baryon masses to agree with their experimental values within sub-percent level uncertainties. Moreover, we determine SU(3) and SU(2) chiral perturbation theory low energy constants, including the octet and the Ω baryon sigma terms σ πN = 43 . 9(4 . 7) MeV, σ π Λ = 28.2 5.4 4.3 MeV, σ π Σ = 25.9 6.1 3.8 MeV, σ π Ξ = 11.2 6.4 4.5 and σ π Ω = 6.9 4.3 5.3 MeV, as well as various parameters, renormalization factors and improvement coefficients that are relevant for simulations with our lattice action.

A bstract We describe a new set of gauge configurations generated within the CLS effort. These ensembles have N f = 2 + 1 flavors of non-perturbatively improved Wilson fermions in the sea with the Lüscher-Weisz action used for the gluons. Open boundary conditions in time are used to address the problem of topological freezing at small lattice spacings and twisted-mass reweighting for improved stability of the simulations. We give the bare parameters at which the ensembles have been generated and how these parameters have been chosen. Details of the algorithmic setup and its performance are presented as well as measurements of the pion and kaon masses alongside the scale parameter t 0 .

Metabolic pathways regulate immune responses and disrupted metabolism leads to immune dysfunction and disease. Coronavirus disease 2019 (COVID-19) is driven by imbalanced immune responses, yet the role of immunometabolism in COVID-19 pathogenesis remains unclear. By investigating 87 patients with confirmed SARS-CoV-2 infection, 6 critically ill non-COVID-19 patients, and 47 uninfected controls, we found an immunometabolic dysregulation in patients with progressed COVID-19. Specifically, T cells, monocytes, and granulocytes exhibited increased mitochondrial mass, yet only T cells accumulated intracellular reactive oxygen species (ROS), were metabolically quiescent, and showed a disrupted mitochondrial architecture. During recovery, T cell ROS decreased to match the uninfected controls. Transcriptionally, T cells from severe/critical COVID-19 patients showed an induction of ROS-responsive genes as well as genes related to mitochondrial function and the basigin network. Basigin (CD147) ligands cyclophilin A and the SARS-CoV-2 spike protein triggered ROS production in T cells in vitro. In line with this, only PCR-positive patients showed increased ROS levels. Dexamethasone treatment resulted in a downregulation of ROS in vitro and T cells from dexamethasone-treated patients exhibited low ROS and basigin levels. This was reflected by changes in the transcriptional landscape. Our findings provide evidence of an immunometabolic dysregulation in COVID-19 that can be mitigated by dexamethasone treatment.

A bstract We present results of the first ab initio lattice QCD calculation of the normalization constants and first moments of the leading twist distribution amplitudes of the full baryon octet, corresponding to the small transverse distance limit of the associated S -wave light-cone wave functions. The P -wave (higher twist) normalization constants are evaluated as well. The calculation is done using N f = 2 + 1 flavors of dynamical (clover) fermions on lattices of different volumes and pion masses down to 222 MeV. Significant SU(3) flavor symmetry violation effects in the shape of the distribution amplitudes are observed.

Abstract We determine the light baryon spectrum on ensembles generated by the Coordinated Lattice Simulations (CLS) effort, employing N f = 2 + 1 flavours of non-perturbatively improved Wilson fermions. The hadron masses are interpolated and extrapolated within the quark mass plane, utilizing three distinct trajectories, two of which intersect close to the physical quark mass point and the third one approaching the SU(3) chiral limit. The results are extrapolated to the continuum limit, utilizing six different lattice spacings ranging from a ≈ 0.10 fm down to below 0.04 fm. The light pion mass varies from M π ≈ 429 MeV down to 127 MeV. In general, the spatial extent is kept larger than four times the inverse pion mass and larger than 2.3 fm, with additional small and large volume ensembles to investigate finite size effects. We determine the Wilson flow scales t 0 , ph = 0.1449 9 7 fm$$ \\sqrt{t_{0,\\textrm{ph}}}={0.1449}_{(9)}^{(7)}\\textrm{fm} $$[1] and t 0 ∗ ≈ t 0 , ph$$ {t}_0^{\\ast}\\approx {t}_{0,\\textrm{ph}} $$[2] from the octet cascade (Ξ baryon). Determining the light baryon spectrum in the continuum limit, we find the nucleon mass m N = 941.7 7.6 6.5$$ {m}_N={941.7}_{(7.6)}^{(6.5)} $$MeV and the other stable baryon masses to agree with their experimental values within sub-percent level uncertainties. Moreover, we determine SU(3) and SU(2) chiral perturbation theory low energy constants, including the octet and the Ω baryon sigma terms σ πN = 43.9(4.7) MeV, σ π Λ = 28.2 5.4 4.3$$ {\\sigma}_{\\pi \\Lambda}={28.2}_{(5.4)}^{(4.3)} $$MeV, σ π Σ = 25.9 6.1 3.8$$ {\\sigma}_{\\pi \\Sigma}={25.9}_{(6.1)}^{(3.8)} $$MeV, σ π Ξ = 11.2 6.4 4.5$$ {\\sigma}_{\\pi \\Xi}={11.2}_{(6.4)}^{(4.5)} $$and σ π Ω = 6.9 4.3 5.3$$ {\\sigma}_{\\pi \\Omega}={6.9}_{(4.3)}^{(5.3)} $$MeV, as well as various parameters, renormalization factors and improvement coefficients that are relevant for simulations with our lattice action.

In this Letter, we provide a determination of the coupling constant in three-flavor quantum chromodynamics (QCD), \\(^MS_s()\\), for \\(MS\\) renormalization scales \\( ın (1,\\,2)\\) GeV. The computation uses gauge field configuration ensembles with \\(O(a)\\)-improved Wilson-clover fermions generated by the Coordinated Lattice Simulations (CLS) consortium. Our approach is based on current-current correlation functions and has never been applied before in this context. We convert the results perturbatively to the QCD \\(\\)-parameter and obtain \\(_MS^N_f=3 = 342 17\\) MeV, which agrees with the world average published by the Particle Data Group and has competing precision. The latter was made possible by a unique combination of state-of-the-art CLS ensembles with very fine lattice spacings, further reduction of discretization effects from a dedicated numerical stochastic perturbation theory simulation, combining data from vector and axial-vector channels and matching to high-order perturbation theory.