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The Deep Underground Neutrino Experiment (DUNE) is an upcoming neutrino oscillation experiment that is poised to answer key questions about the nature of neutrinos. Lattice QCD has the ability to make significant impact upon DUNE, beginning with computations of nucleon-neutrino interactions with weak currents. Nucleon amplitudes involving the axial form factor are part of the primary signal measurement process for DUNE, and precise calculations from LQCD can significantly reduce the uncertainty for inputs into Monte Carlo generators. Recent calculations of the nucleon axial charge have demonstrated that sub-percent precision is possible on this vital quantity. In these proceedings, we discuss preliminary results for the CalLat collaboration's calculation of the axial form factor of the nucleon. These computations are performed with Möbius domain wall valence quarks on HISQ sea quark ensembles generated by the MILC and CalLat collaborations. The results use a variety of ensembles including several at physical pion mass.

Lattice QCD calculations of two-nucleon interactions have been underway for about a decade, but still haven't reached the pion mass regime necessary for matching onto effective field theories and extrapolating to the physical point. Furthermore, results from different methods, including the use of the Lüscher formalism with different types of operators, as well as the HALQCD potential method, do not agree even qualitatively at very heavy pion mass. We investigate the role that different operators employed in the literature may play on the extraction of spectra for use within the Lüscher method. We first explore expectations from Effective Field Theory solved within a finite volume, for which the exact spectrum may be computed given different physical scenarios. We then present preliminary lattice QCD results for two-nucleon spectra calculated using different operators on a common lattice ensemble.

We report on a subpercent scale determination using the omega baryon mass and gradient-flow methods. The calculations are performed on 22 ensembles of Nf=2+1+1 highly improved, rooted staggered sea-quark configurations generated by the MILC and CalLat Collaborations. The valence quark action used is Möbius domain wall fermions solved on these configurations after a gradient-flow smearing is applied with a flowtime of tgf=1 in lattice units. The ensembles span four lattice spacings in the range 0.06a0.15 fm, six pion masses in the range 130mπ400 MeV and multiple lattice volumes. On each ensemble, the gradient-flow scales t0/a2 and w0/a and the omega baryon mass amω are computed. The dimensionless product of these quantities is then extrapolated to the continuum and infinite volume limits and interpolated to the physical light, strange and charm quark mass point in the isospin limit, resulting in the determination of t0=0.1422(14) fm and w0=0.1709(11) fm with all sources of statistical and systematic uncertainty accounted for. The dominant uncertainty in both results is the stochastic uncertainty, though for t0 there are comparable continuum extrapolation uncertainties. For w0, there is a clear path for a few-per-mille uncertainty just through improved stochastic precision, as recently obtained by the Budapest-Marseille-Wuppertal Collaboration.

We report on the first application of the stochastic Laplacian Heaviside method for computing multiparticle interactions with lattice QCD to the two-nucleon system. Like the Laplacian Heaviside method, this method allows for the construction of interpolating operators which can be used to construct a set of positive-definite two-nucleon correlation functions, unlike nearly all other applications of lattice QCD to two nucleons in the literature. It also allows for a variational analysis in which optimal linear combinations of the interpolating operators are formed that couple predominantly to the eigenstates of the system. Utilizing such methods has become of paramount importance to help resolve the discrepancy in the literature on whether two nucleons in either isospin channel form a bound state at pion masses heavier than physical, with the discrepancy persisting even in the SU(3)-flavor-symmetric point with all quark masses near the physical strange quark mass. This is the first in a series of papers aimed at resolving this discrepancy. In the present work, we employ the stochastic Laplacian Heaviside method without a hexaquark operator in the basis at a lattice spacing of a≈0.086 fm, lattice volume of L=48a≈4.1 fm and pion mass mπ≈714 MeV. With this setup, the observed spectrum of two-nucleon energy levels strongly disfavors the presence of a bound state in either the deuteron or dineutron channel.

Observation of neutrinoless double beta decay, a lepton number violating process that has been proposed to clarify the nature of neutrino masses, has spawned an enormous world-wide experimental effort. Relating nuclear decay rates to high-energy, beyond the standard model (BSM) physics requires detailed knowledge of nonperturbative QCD effects. Using lattice QCD, we compute the necessary matrix elements of short-range operators, which arise due to heavy BSM mediators, that contribute to this decay via the leading order π^{-}→π^{+} exchange diagrams. Utilizing our result and taking advantage of effective field theory methods will allow for model-independent calculations of the relevant two-nucleon decay, which may then be used as input for nuclear many-body calculations of the relevant experimental decays. Contributions from short-range operators may prove to be equally important to, or even more important than, those from long-range Majorana neutrino exchange.

The axial coupling of the nucleon, gA, is the strength of its coupling to the weak axial current of the standard model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic current. This axial coupling dictates the rate at which neutrons decay to protons, the strength of the attractive long-range force between nucleons and other features of nuclear physics. Precision tests of the standard model in nuclear environments require a quantitative understanding of nuclear physics that is rooted in quantum chromodynamics, a pillar of the standard model. The importance of gA makes it a benchmark quantity to determine theoretically-a difficult task because quantum chromodynamics is non-perturbative, precluding known analytical methods. Lattice quantum chromodynamics provides a rigorous, non-perturbative definition of quantum chromodynamics that can be implemented numerically. It has been estimated that a precision of two per cent would be possible by 2020 if two challenges are overcome1,2: contamination of gA from excited states must be controlled in the calculations and statistical precision must be improved markedly2-10. Here we use an unconventional method 11 inspired by the Feynman-Hellmann theorem that overcomes these challenges. We calculate a gA value of 1.271 ± 0.013, which has a precision of about one per cent.

We report on salient features of a mixed lattice QCD action using valence Möbius domain-wall fermions solved on the dynamical Nf=2+1+1 highly improved staggered quark sea-quark ensembles generated by the MILC Collaboration. The approximate chiral symmetry properties of the valence fermions are shown to be significantly improved by utilizing the gradient-flow scheme to first smear the highly improved staggered quark configurations. The greater numerical cost of the Möbius domain-wall inversions is mitigated by the highly efficient QUDA library optimized for NVIDIA GPU accelerated compute nodes. We have created an interface to this optimized QUDA solver in Chroma. We provide tuned parameters of the action and performance of QUDA using ensembles with the lattice spacings a≃{0.15,0.12,0.09} fm and pion masses mπ≃{310,220,130} MeV. We have additionally generated two new ensembles with a∼0.12 fm and mπ∼{400,350} MeV. With a fixed flow time of tgf=1 in lattice units, the residual chiral symmetry breaking of the valence fermions is kept below 10% of the light quark mass on all ensembles, mres0.1×ml, with moderate values of the fifth dimension L5 and a domain-wall height M5≤1.3. As a benchmark calculation, we perform a continuum, infinite volume, physical pion and kaon mass extrapolation of FK±/Fπ± and demonstrate our results are independent of flow time and consistent with the FLAG determination of this quantity at the level of less than one standard deviation.

We present a determination of nucleon-nucleon scattering phase shifts for ℓ≥0. The S, P, D and F phase shifts for both the spin-triplet and spin-singlet channels are computed with lattice Quantum ChromoDynamics. For ℓ>0, this is the first lattice QCD calculation using the Lüscher finite-volume formalism. This required the design and implementation of novel lattice methods involving displaced sources and momentum-space cubic sinks. To demonstrate the utility of our approach, the calculations were performed in the SU(3)-flavor limit where the light quark masses have been tuned to the physical strange quark mass, corresponding to mπ=mK≈800 MeV. In this work, we have assumed that only the lowest partial waves contribute to each channel, ignoring the unphysical partial wave mixing that arises within the finite-volume formalism. This assumption is only valid for sufficiently low energies; we present evidence that it holds for our study using two different channels. Two spatial volumes of V≈(3.5 fm)3 and V≈(4.6 fm)3 were used. The finite-volume spectrum is extracted from the exponential falloff of the correlation functions. Said spectrum is mapped onto the infinite volume phase shifts using the generalization of the Lüscher formalism for two-nucleon systems.

The present study investigates the modal stability of the steady incompressible flow inside a toroidal pipe for values of the curvature δ (ratio between pipe and torus radii) approaching zero, i.e. the limit of a straight pipe. The global neutral stability curve for 10-7 ≤ δ ≤ 10-2 is traced using a continuation algorithm. Two different families of unstable eigenmodes are identified. For curvatures below 1.5 × 10-6, the critical Reynolds number Recr is proportional to δ -1/2. Hence, the critical Dean number is constant, Decr = 2 Recr √ δ ≈ 113. This behaviour confirms that the Hagen-Poiseuille flow is stable to infinitesimal perturbations for any Reynolds number and suggests that a continuous transition from the curved to the straight pipe takes place as far as it regards the stability properties. For low values of the curvature, an approximate self-similar solution for the steady base flow can be obtained at a fixed Dean number. Exploiting the proposed semi-analytic scaling in the stability analysis provides satisfactory results. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs), can be employed as standardized candles, extending the distance ladder beyond Type Ia supernovae (SNe Ia, z  = 2.26). We standardize GRBs using the three-dimensional (3D) Fundamental Plane relation (the Dainotti relation) among the rest-frame end time of the X-ray plateau emission, its corresponding luminosity, and the peak prompt luminosity. Combining SNe Ia and GRBs, we constrain ΩM = 0.299 ± 0.009 assuming a flat Λ cold dark matter (ΛCDM) cosmology with and without correcting GRBs for selection biases and redshift evolution. Using a 3D optical Dainotti correlation, we find this sample is as efficacious in the determination of ΩM as the X-ray sample. We trimmed our GRB samples to achieve tighter planes to simulate additional GRBs. We determined how many GRBs are needed as stand-alone probes to achieve a comparable precision on ΩM to the one obtained by SNe Ia only. We reach the same error measurements derived using SNe Ia in 2011 and 2014 with 142 and 284 simulated optical GRBs, respectively, considering the error bars on the variables halved. These error limits will be reached in 2038 and in 2047, respectively. Using a doubled sample (obtained by future machine learning approaches allowing a light-curve reconstruction and the estimates of GRB redshifts when z is unknown) compared to the current sample, with error bars halved we will reach the same precision as SNe Ia in 2011 and 2014, now and in 2026, respectively. If we consider the current SNe precision, this will be reached with 390 optical GRBs by 2054. [ABSTRACT FROM AUTHOR]

Moreover, anakinra represents a treatment option for paediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS-TS), a clinical entity characterized by fever, increased inflammatory markers, and single- or multi-organ dysfunction, described in children during or recently recovered from COVID-19 ([2], [3]). In March 2020, an 82-year-old man symptomatic for fever and mild dyspnoea was diagnosed with COVID-19 after the positive result of a polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The recombinant interleukin-1 (IL-1) receptor antagonist anakinra has recently received approval for the management of coronavirus disease 2019 (COVID-19) patients with respiratory failure and hyperinflammation ([1]). [Extracted from the article]

Aims: To describe the clinical phenotype of X linked juvenile retinoschisis in eight Italian families with six different mutations in the XLRS1 gene. Methods: Complete ophthalmic examinations, electroretinography and A [...]

The Hubble constant (H0) tension between Type Ia supernovae (SNe Ia) and Planck measurements ranges from 4 to 6σ. To investigate this tension, we estimate H0 in the ΛCDM and CDM (cold dark matter) models by dividing the Pantheon sample, the largest compilation of SNe Ia, into 3, 4, 20, and 40 bins. We fit the extracted H0 values with a function mimicking the redshift evolution: , where α indicates an evolutionary parameter and at z = 0. We set the absolute magnitude of SNe Ia so that , and we fix fiducial values for and. We find that H0 evolves with redshift, showing a slowly decreasing trend, with α coefficients consistent with zero only from 1.2 to 2.0σ. Although the α coefficients are compatible with zero in 3σ, this however may affect cosmological results. We measure locally a variation of in three and four bins. Extrapolating to z = 1100, the redshift of the last scattering surface, we obtain values of H0 compatible in 1σ with Planck measurements independent of the cosmological models and number of bins we investigated. Thus, we have reduced the H0 tension in the range from 54% to 72% for both cosmological models. If the decreasing trend of is real, it could be due to astrophysical selection effects or to modified gravity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Right ventricle and pulmonary artery pressure have always received less attention in type 1 diabetes than left ventricle. The aim of this study is to compare the right heart performance and the estimated peak systolic pulmonary artery pressure (EPSPAP) in young type 1 diabetes patients with healthy controls. PATIENTS AND METHODS: Subjects affected by type 1 diabetes without cardiovascular and respiratory diseases (n=93) and healthy controls (n=56) were evaluated with a comprehensive transthoracic echocardiography. The pulmonary peak systolic arterial pressure was calculated with an established formula based on pulmonary artery acceleration time. RESULTS: The left ventricle's function was found to be normal in all the subjects under study. The estimated peak systolic pulmonary artery pressure was significantly higher in patients with type 1 diabetes compared to the controls (38.5 ± 8.6 vs. 35.4 ± 6.7, p = 0.019). The highest value of EPSPAP was observed in smoking female patients with type 1 diabetes. Basal and mid cavity diameter of the right ventricle were higher in patients with type 1 diabetes. Factors associated with EPSPAP were sex, body mass index, mid cavity diameter and, with an inverse correlation, HDL-cholesterol. CONCLUSIONS: The present study suggests that young, uncomplicated patients with type 1 diabetes have a higher estimated peak systolic pulmonary artery pressure. Further studies are needed to define the mechanisms underlying this alteration and its clinical consequences. [ABSTRACT FROM AUTHOR]