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Excited state contamination remains one of the most challenging sources of systematic uncertainty to control in lattice QCD calculations of nucleon matrix elements and form factors: early time separations are contaminated by excited states and late times suffer from an exponentially bad signal-to-noise problem. High-statistics calculations at large time separations $\gtrsim1$ fm are commonly used to combat these issues. In this work, focusing on $g_A$, we explore the alternative strategy of utilizing a large number of relatively low-statistics calculations at short to medium time separations (0.2--1 fm), combined with a multi-state analysis. On an ensemble with a pion mass of approximately 310 MeV and a lattice spacing of approximately 0.09 fm, we find this provides a more robust and economical method of quantifying and controlling the excited state systematic uncertainty. A quantitative separation of various types of excited states enables the identification of the transition matrix elements as the dominant contamination. The excited state contamination of the Feynman-Hellmann correlation function is found to reduce to the 1% level at approximately 1 fm while for the more standard three-point functions, this does not occur until after 2 fm. Critical to our findings is the use of a global minimization, rather than fixing the spectrum from the two-point functions and using them as input to the three-point analysis. We find that the ground state parameters determined in such a global analysis are stable against variations in the excited state model, the number of excited states, and the truncation of early-time or late-time numerical data., Comment: v2: updates based on referee comments and some community response, consistent with published version; v1: 13 pages plus appendices. The correlation function data and analysis code accompanying this publication can be accessed at this github repository: https://github.com/callat-qcd/project_fh_vs_3pt

We report on a subpercent scale determination using the omega baryon mass and gradient-flow methods. The calculations are performed on 22 ensembles of ${N}_{f}=2+1+1$ highly improved, rooted staggered sea-quark configurations generated by the MILC and CalLat Collaborations. The valence quark action used is M\"obius domain wall fermions solved on these configurations after a gradient-flow smearing is applied with a flowtime of ${t}_{\mathrm{gf}}=1$ in lattice units. The ensembles span four lattice spacings in the range $0.06\ensuremath{\lesssim}a\ensuremath{\lesssim}0.15\text{ }\text{ }\mathrm{fm}$, six pion masses in the range $130\ensuremath{\lesssim}{m}_{\ensuremath{\pi}}\ensuremath{\lesssim}400\text{ }\text{ }\mathrm{MeV}$ and multiple lattice volumes. On each ensemble, the gradient-flow scales ${t}_{0}/{a}^{2}$ and ${w}_{0}/a$ and the omega baryon mass $a{m}_{\mathrm{\ensuremath{\Omega}}}$ 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 $\sqrt{{t}_{0}}=0.1422(14)\text{ }\text{ }\mathrm{fm}$ and ${w}_{0}=0.1709(11)\text{ }\text{ }\mathrm{fm}$ with all sources of statistical and systematic uncertainty accounted for. The dominant uncertainty in both results is the stochastic uncertainty, though for $\sqrt{{t}_{0}}$ there are comparable continuum extrapolation uncertainties. For ${w}_{0}$, 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.

In this study, we present a determination of the unpolarized gluon Ioffe-time distribution in the nucleon from a first principles lattice quantum chromodynamics calculation. We carry out the lattice calculation on a $32^3\times 64$ ensemble with a pion mass of $358$ MeV and lattice spacing of $0.094$ fm. We construct the nucleon interpolating fields using the distillation technique, flow the gauge fields using the gradient flow, and solve the summed generalized eigenvalue problem to determine the glounic matrix elements. Combining these techniques allows us to provide a statistically well-controlled Ioffe-time distribution and unpolarized gluon PDF. We obtain the flow time independent reduced Ioffe-time pseudo-distribution, and calculate the light-cone Ioffe-time distribution and unpolarized gluon distribution function in the $\overline{\rm MS}$ scheme at $\mu = 2$ GeV, neglecting the mixing of the gluon operator with the quark singlet sector. Finally, we compare our results to phenomenological determinations., Comment: 23 pages, 12 figures, Phys Rev D accepted version

Measurements of a permanent neutron electric dipole moment (EDM) potentially probe Beyond-the-Standard Model (BSM) sources of CP-violation. At low energy the CP-violating BSM interactions are parametrized by flavor-conserving CP-violating operators of dimension higher than four. QCD calculations of the nucleon matrix elements of these operators are required to fully reconstruct the sources and magnitudes of the different CP-violating contributions to the nucleon EDM. Herein we study the quark-chromo electric dipole moment (qCEDM) operator and the three-gluon Weinberg operator. The non-perturbative determination, using lattice QCD, of the nucleon matrix elements of these CP-violating operators is hampered by their short-distance behavior. Under renormalization these operators mix with lower dimensional operators, which induces power divergences in the lattice spacing, as the continuum limit is approached. We study the short-distance behavior of the qCEDM and the Weinberg operators using the gradient flow. We perform a short flow time expansion and determine, in perturbation theory, the expansion coefficients of the linearly-divergent terms stemming from the mixing with the pseudoscalar density and the topological charge, confirming the expectations of the operator product expansion. We introduce a new method to perform calculations at non-zero flow-time for arbitrary values of the external momenta. This method allows us to work in four dimensions for most of the calculations described in this paper, avoiding the complications associated with defining $\gamma_5$ in generic d dimensions. We show that leading contributions in the external momenta can be reproduced by defining $\gamma_5$ using the 't Hooft-Veltman-Breitenlohner-Maison scheme., Comment: 23 pages, 3 figures

We report the results of a lattice quantum chromodynamics calculation of ${F}_{K}/{F}_{\ensuremath{\pi}}$ using M\"obius domain-wall fermions computed on gradient-flowed ${N}_{f}=2+1+1$ highly improved staggered quark (HISQ) ensembles. The calculation is performed with five values of the pion mass ranging from $130\ensuremath{\lesssim}{m}_{\ensuremath{\pi}}\ensuremath{\lesssim}400\text{ }\text{ }\mathrm{MeV}$, four lattice spacings of $a\ensuremath{\sim}0.15$, 0.12, 0.09 and 0.06 fm and multiple values of the lattice volume. The interpolation/extrapolation to the physical pion and kaon mass point, the continuum, and infinite volume limits are performed with a variety of different extrapolation functions utilizing both the relevant mixed-action effective field theory expressions as well as discretization-enhanced continuum chiral perturbation theory formulas. We find that the $a\ensuremath{\sim}0.06\text{ }\text{ }\mathrm{fm}$ ensemble is helpful, but not necessary to achieve a subpercent determination of ${F}_{K}/{F}_{\ensuremath{\pi}}$. We also include an estimate of the strong isospin breaking corrections and arrive at a final result of ${F}_{{\stackrel{^}{K}}^{+}}/{F}_{{\stackrel{^}{\ensuremath{\pi}}}^{+}}=1.1942(45)$ with all sources of statistical and systematic uncertainty included. This is consistent with the Flavour Lattice Averaging Group average value, providing an important benchmark for our lattice action. Combining our result with experimental measurements of the pion and kaon leptonic decays leads to a determination of $|{V}_{us}|/|{V}_{ud}|=0.2311(10)$.

Predicting the Bs0−B¯s0 width difference ΔΓs relies on the heavy quark expansion and on hadronic matrix elements of ΔB=2 operators. We present the first lattice QCD results for matrix elements of the dimension-7 operators R2,3 and linear combinations R˜2,3 using nonrelativistic QCD for the bottom quark and a highly improved staggered quark (HISQ) action for the strange quark. Computations use MILC Collaboration ensembles of gauge field configurations with 2+1+1 flavors of sea quarks with the HISQ discretization, including lattices with physically light up or down quark masses. We discuss features unique to calculating matrix elements of these operators and analyze uncertainties from series truncation, discretization, and quark mass dependence. Finally we report the first standard model determination of ΔΓs using lattice QCD results for all hadronic matrix elements through O(1/mb). The main result of our calculations yields the 1/mb contribution ΔΓ1/mb=−0.022(10) ps−1. Adding this to the leading order contribution, the standard model prediction is ΔΓs=0.092(14) ps−1.

We calculate the bag parameters for neutral $B$-meson mixing in and beyond the Standard Model, in full four-flavour lattice QCD for the first time. We work on gluon field configurations that include the effect of $u$, $d$, $s$ and $c$ sea quarks with the Highly Improved Staggered Quark (HISQ) action at three values of the lattice spacing and with three $u/d$ quark masses going down to the physical value. The valence $b$ quarks use the improved NRQCD action and the valence light quarks, the HISQ action. Our analysis was blinded. Our results for the bag parameters for all five operators are the most accurate to date. For the Standard Model operator between $B_s$ and $B_d$ mesons we find: $\hat{B}_{B_s}=1.232(53)$, $\hat{B}_{B_d}=1.222(61)$. Combining our results with lattice QCD calculations of the decay constants using HISQ quarks from the Fermilab/MILC collaboration and with experimental values for $B_s$ and $B_d$ oscillation frequencies allows determination of the CKM elements $V_{ts}$ and $V_{td}$. We find $V_{ts} = 0.04189(93)$, $V_{td} = 0.00867(23)$ and $V_{ts}/V_{td} = 0.2071(27)$. Our results agree well (within $2\sigma$) with values determined from CKM unitarity constraints based on tree-level processes (only). Using a ratio to $\Delta M$ in which CKM elements cancel in the Standard Model, we determine the branching fractions ${\text{Br}}(B_s\rightarrow \mu^+\mu^-) = 3.81(18) \times 10^{-9}$ and ${\text{Br}}(B_d\rightarrow \mu^+\mu^-) = 1.031(54) \times 10^{-10}$. We also give results for matrix elements of the operators $R_0$, $R_1$ and $\tilde{R}_1$ that contribute to neutral $B$-meson width differences., Comment: 27 pages, 16 figures. Slight changes to text to clarify arguments. Updated Figure 10. Version accepted by Physical Review D

Predicting the B_{s}^{0}-B[over ¯]_{s}^{0} width difference ΔΓ_{s} relies on the heavy quark expansion and on hadronic matrix elements of ΔB=2 operators. We present the first lattice QCD results for matrix elements of the dimension-7 operators R_{2,3} and linear combinations R[over ˜]_{2,3} using nonrelativistic QCD for the bottom quark and a highly improved staggered quark (HISQ) action for the strange quark. Computations use MILC Collaboration ensembles of gauge field configurations with 2+1+1 flavors of sea quarks with the HISQ discretization, including lattices with physically light up or down quark masses. We discuss features unique to calculating matrix elements of these operators and analyze uncertainties from series truncation, discretization, and quark mass dependence. Finally we report the first standard model determination of ΔΓ_{s} using lattice QCD results for all hadronic matrix elements through O(1/m_{b}). The main result of our calculations yields the 1/m_{b} contribution ΔΓ_{1/m_{b}}=-0.022(10) ps^{-1}. Adding this to the leading order contribution, the standard model prediction is ΔΓ_{s}=0.092(14) ps^{-1}.

We present a lattice quantum chromodynamics determination of the ratio of the scalar and vector form factors for two semileptonic decays of the ${B}_{s}$ meson: ${B}_{s}\ensuremath{\rightarrow}K\ensuremath{\ell}\ensuremath{\nu}$ and ${B}_{s}\ensuremath{\rightarrow}{D}_{s}\ensuremath{\ell}\ensuremath{\nu}$. In conjunction with future experimental data, our results for these correlated form factors will provide a new method to extract $|{V}_{ub}/{V}_{cb}|$, which may elucidate the current tension between exclusive and inclusive determinations of these Cabibbo-Kobayashi-Maskawa mixing matrix parameters. In addition to the form factor results, we determine the ratio of the differential decay rates, and forward-backward and polarization asymmetries, for the two decays.

The current study aim was to examine mental health characteristics in a sample of returning OEF/OIF/OND veterans initially enrolling in Department of Veterans Affairs (VA) health care (N = 1,307), with a particular focus on a subgroup considered at risk for suicide (N = 445). Methods included examination of mental health screening measures and clinical interview data from a VA postdeployment clinic. Half of the sample met criteria for a mental health disorder, whereas 10% reported current suicidal or death ideation (e.g., thoughts of being better off dead or hurting oneself in some way) and 6% reported a history of suicide attempt. Sixty-eight percent of the at-risk subgroup accepted a referral for mental health treatment and a promising majority (78%) of those individuals attended their initial specialty mental health visit. At-risk veterans who accepted mental health referral were more likely to report current suicidal/death ideation; they were also more likely to have a diagnosis of a depressive disorder, anxiety disorder, or posttraumatic stress disorder. Factors associated with mental health appointment attendance included older age, being enrolled in college, and more years of military service. Results highlight the importance of early screening and referral to appropriate mental health follow-up. Implications for clinical practice and increasing engagement in VA mental health services among veterans at risk for suicide are discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Spatially non-local matrix elements are useful lattice-QCD observables in a variety of contexts, for example in determining hadron structure. To quote credible estimates of the systematic uncertainties in these calculations, one must understand, among other things, the size of the finite-volume effects when such matrix elements are extracted from numerical lattice calculations. In this work, we estimate finite-volume effects for matrix elements of non-local operators, composed of two currents displaced in a spatial direction by a distance $\xi$. We find that the finite-volume corrections depend on the details of the matrix element. If the external state is the lightest degree of freedom in the theory, e.g.~the pion in QCD, then the volume corrections scale as $ e^{-m_\pi (L- \xi)} $, where $m_\pi$ is the mass of the light state. For heavier external states the usual $e^{- m_\pi L}$ form is recovered, but with a polynomial prefactor of the form $L^m/|L - \xi|^n$ that can lead to enhanced volume effects. These observations are potentially relevant to a wide variety of observables being studied using lattice QCD, including parton distribution functions, double-beta-decay and Compton-scattering matrix elements, and long-range weak matrix elements., Comment: 15 pages, 4 figures

We show that the correct way to extract parton distribution functions from the reduced Ioffe-time distribution, a ratio of the Ioffe-time distribution for a moving hadron and a hadron at rest, is through a factorization formula. This factorization exists because, at small distances, forming the ratio does not change the infrared behavior of the numerator, which is factorizable. We illustrate the effect of such a factorization by applying it to results in the literature., SCOAP3

Hazardous drinking among US Military combat veterans is an important public health issue. Because recent combat veterans are difficult to engage in specialty mental health and substance abuse care, there is a need for opportunistic interventions administered in settings visited by recent combat veterans such as primary care. This paper describes a brief (single-session) intervention that was recently developed and tested in a sample of veterans of Operations Enduring Freedom, Iraqi Freedom and New Dawn (OEF/OIF/OND). The intervention consists of a counseling session delivered in a Motivational Interviewing style using a packet of personalized feedback about alcohol misuse, symptoms of PTSD and depression, as well as coping skills. The treatment is described and data from a single case treated with this intervention are presented. Language: en

Brief alcohol interventions (BAIs) have been widely adopted for use with college students and are associated with significant reductions in drinking and problems. However, many students do not respond to these approaches and little is known about risk factors for poor response. The current study investigated one possible risk factor by examining the impact of posttraumatic stress (PTS) symptoms on BAI efficacy. This study presents pooled data from two randomized clinical trials that examined the efficacy of counselor-administered BAIs compared with computerized interventions. Participants were 207 college students (53.1% women, 68.1% White/Caucasian, 16.9% with elevated post-traumatic stress) who reported past-month heavy episodic drinking. Follow-up assessments were completed six months post-intervention. Analyses testing differences in frequency of past-month heavy episodic drinking revealed a significant post-traumatic stress by time interaction (F(1,165) = 8.27, p = .005) such that individuals screening positive for PTS showed larger reductions in heavy episodic drinking at follow-up. A significant three-way interaction between time, PTS, and intervention condition (F(2,167) = 5.76, p = .004) was found for alcohol related consequences. Specifically, among individuals screening positive for PTS, only those that received the counselor-administered BAI showed a significant reduction in consequences at follow-up. These results suggest that overall college students with PTS may respond well to BAIs and that counselor-delivered BAIs may be more efficacious than computer-delivered interventions for reducing alcohol problems for these high-risk students.

We give a progress report on a project aimed at a high-precision calculation of the decay constants $f_B$ and $$f_{B_s}$$ from simulations with HISQ heavy and light valence and sea quarks. Calculations are carried out with several heavy valence-quark masses on ensembles with 2+1+1 flavors of HISQ sea quarks at five lattice spacings and several light sea-quark mass ratios $$m_{ud}/m_s$$, including approximately physical sea-quark masses. This range of parameters provides excellent control of the continuum limit and of heavy-quark discretization errors. We present a preliminary error budget with projected uncertainties of 2.2~MeV and 1.5~MeV for $f_B$ and $$f_{B_s}$$, respectively.

College students exhibit high levels of heavy drinking that are often associated with negative consequences, including unsafe sexual activity, injury, and legal trouble. The fact that students continue to drink despite these outcomes suggests they experience salient positive consequences. A known risk factor of drinking is the personality trait sensation seeking (SS), which may influence how a person interprets alcohol-related consequences and ultimately result in increased alcohol consumption. In this study, we examined the relations between SS, positive and negative consequences, and drinking among college students. Participants were 206 undergraduates who reported recent heavy drinking (53% female, 65% white, and 26% African-American). Students with higher levels of SS reported drinking more and also indicated experiencing more positive consequences as a result of their drinking than participants with lower levels of SS. This relation between SS and drinking was mediated by positive consequences, sugge...

OBJECTIVES: This study investigated the relations between post-trauma psychopathology and substance abuse in a sample of trauma-exposed college students (n = 136) assigned to four groups based on primary diagnosis: posttraumatic stress disorder, depression, social phobia, or well-adjusted (participants who had low levels of distress). Groups were compared on a series of dimensions of substance use/abuse. RESULTS: Participants in the PTSD group evidenced greater substance use and abuse than those in the social phobia and well-adjusted groups on several dimensions and greater alcohol consumption than the depressed group. Correlation analyses suggested that most dimensions of substance abuse were related more strongly to avoidance and numbing (cluster C) symptoms than to reexperiencing and hyperarousal. CONCLUSIONS: The present findings suggest that trauma-related psychopathology may be associated with a more hazardous pattern of substance use than depression and social phobia.

We propose a new locally smeared operator product expansion to decompose nonlocal operators in terms of a basis of smeared operators. The smeared operator product expansion formally connects nonperturbative matrix elements determined numerically using lattice field theory to matrix elements of nonlocal operators in the continuum. These nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, which significantly complicates calculations of quantities such as the moments of parton distribution functions, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale complicates the connection to the Wilson coefficients of the standard operator product expansion and requires the construction of a suitable formalism. We demonstrate the feasibility of our approach with examples in real scalar field theory., 11 pages, 7 figures. Version accepted by Phys. Rev. D. Minor changes: references updated and a couple of paragraphs clarified

This study examined patterns of drinking motives endorsed by heavy drinking veterans who either did or did not meet criteria for posttraumatic stress disorder (PTSD).Data were collected from 69 veterans of Operations Enduring Freedom or Iraqi Freedom (OEF/OIF) who had screened positive for hazardous drinking. The sample was 91.3% male and 65.2% Caucasian. Based on a structured interview, 58% of the sample met criteria for PTSD.The PTSD group scored higher than the non-PTSD group on scales measuring drinking to cope with anxiety and depression and similarly to the non-PTSD group on scales measuring social, enhancement and conformity motives. Coping and social motives were significantly correlated with adverse alcohol consequences. Overall, the PTSD group showed stronger relations between coping scales and aspects of alcohol misuse, relative to the non- PTSD group.These findings suggest first, that among heavy drinking OEF/OIF veterans there is a high base rate of PTSD. Second, coping motives are frequently reported in this population, and they seem to be related to a more severe pattern of alcohol-related consequences. These findings underscore the importance of assessing the interplay between PTSD and substance abuse in trauma-exposed samples.

Although DSM-IV-TR diagnostic criteria for posttraumatic stress disorder (PTSD) include three primary symptom clusters, recent evidence from confirmatory factor analyses suggest that the latent structure of PTSD is better represented by four factors, which will likely be reflected in the upcoming DSM-5. Given this likely transition from three to four clusters, the present study sought to examine specific and non-specific aspects of dysphoria in the factor structure of PTSD symptoms in a sample of OEF/OIF combat veterans presenting to a Veterans Affairs primary care clinic. PTSD symptoms were assessed using the PCL-M (Weathers et al. 1993). Results from confirmatory factor analyses suggested that a dysphoria factor involving a number of non-specific distress symptoms may be an important part of the PTSD symptom profile. After controlling for variance due to general psychological distress, we further found that factor loadings on the dysphoria factor were attenuated but continued to significantly load onto the factor, suggesting that dysphoria may be a specific part of the PTSD symptom constellation.

Substance abuse among military combat veterans has become an issue of increasing interest to researchers and clinicians, and one of considerable public health importance, given that over 2 million American military personnel have served in recent combat theatres (Department of Defense, 2010). Research on veterans of the recent conflicts in Iraq and Afghanistan (abbreviated OEF/OIF/OND for Operations Enduring Freedom, Iraqi Freedom, and New Dawn) has demonstrated rates of alcohol misuse in the range of 25 to 40% (Calhoun et al., 2008; Jacobson et al., 2008). There is, unfortunately, a very low rate of help-seeking for substance abuse and mental health concerns in this population. One study found that only 2.5% of service members who screened positive for alcohol misuse had received any substance abuse treatment services (Burnett-Zeigler et al., 2011). Drinking in this population is further complicated by high rates of posttraumatic stress disorder (PTSD; McDevitt-Murphy et al., 2010), which may contribute to coping-motivated drinking, a particularly hazardous pattern (Kuntsche, Knibbe, Gmel, & Engels, 2005). Thus it seems that brief, opportunistic interventions, offered as part of regular medical care might be warranted for this population. To date, no brief intervention trials using samples of OEF/OIF/OND veterans have been published. Brief alcohol interventions Brief alcohol interventions (BAI) hold promise for reducing substance abuse across an array of populations. BAIs have emerged as the treatment of choice for heavy-drinking college students (Carey, Scott-Sheldon, Carey & DeMartini, 2007) and have become an important clinical tool with adults in medical settings (Ballesteros, Duffy, Querejeta, Arino, & Gonzalez-Pinto, 2004). BAIs used with college students typically include two primary components: detailed personalized feedback (usually several pages of written material that summarize the consequences and risks associated with each individual’s alcohol use), and motivational interviewing (MI), a counseling style characterized by a non-judgmental stance that aims to increase participants’ motivation to make positive changes (Miller & Rollnick, 2012). BAIs in medical settings are typically shorter, and provide less detailed feedback (Ballesteros et al., 2004). Given the high level of alcohol misuse among OEF/OIF/OND veterans and the low rate of help-seeking in this population, BAIs may be a particularly relevant type of intervention to explore. The goal of the present study was to develop and compare two brief alcohol interventions for combat veterans, a group with a high level of PTSD symptoms. The impact of PTSD on BAI efficacy has been explored in one prior study (Monahan, McDevitt-Murphy, Dennhardt, Skidmore, Martens, & Murphy, 2013). That study used a sample of college students and found that students who endorsed symptoms of PTSD were responsive to both clinician-administered (MI) and computer administered brief alcohol interventions, but that they showed a better response to the MI intervention with respect to alcohol-related consequences. It is possible that counselor-delivered interventions might be preferable to no-contact interventions for individuals with PTSD due to the high level of negative affect associated with PTSD and the emphasis on empathy in MI. Therefore, a secondary goal of the present study was to examine the role of PTSD as a moderator of treatment effects. In this study, the interventions included both general and personalized information about PTSD and depression symptoms and the ways that these symptoms might influence drinking, whereas the interventions in the Monahan et al study did not explicitly address these symptoms.

We match continuum and lattice heavy-light four-fermion operators at one loop in perturbation theory. For the heavy quarks we use nonrelativistic QCD and for the massless light quarks the highly improved staggered quark action. We include the full set of $\Delta B=2$ operators relevant to neutral $B$ mixing both within and beyond the Standard Model and match through order $\alpha_s$, $\Lambda_{\mathrm{QCD}}/M_b$, and $\alpha_s/(aM_b)$., Comment: 13 pages, 10 figures. Version accepted by Phys. Rev. D: one diagram added (Fig.4) and text updated accordingly. Typographic errors corrected

TheB andBs decay constants are key hadronic parameters in the Standard Model (SM) rate for B(s)! + and B=Bs oscillations, with the B meson decay constant also determining the rate for B! . The combination of experiment and theory for these processes provides important constraints on CKM unitarity [1] and the search for new physics, but the strength of the constraints is typically limited by the errors on the hadronic parameters. The decay constants can only be determined accurately from lattice QCD calculations. Several methods have been developed for this [2], with errors decreasing over the years as calculations have improved. Here we provide a step change in this process, giving the rst results

We match the continuum and lattice axial-vector and vector currents at one loop in perturbation theory. For the heavy quarks we use the nonrelativistic QCD (NRQCD) action and for the light quarks the highly improved staggered quark (HISQ) action. We present results for both massless and massive HISQ quarks and as part of the matching procedure we include a discussion of the one loop HISQ renormalization parameters.

We calculate the one loop renormalisation parameters for the heavy-light axial-vector and vector currents using lattice perturbation theory. We use NonRelativistic QCD (NRQCD) heavy quarks and the Highly Improved Staggered Quark (HISQ) action for the light quarks. We present results for heavy-light currents with massless HISQ quarks and briefly discuss the extension to heavyheavy currents with massive HISQ quarks.

OBJECTIVE: To examine unique contributions of depression, alcohol consumption, and alcohol-related consequences on functional health outcomes in college students. METHODS: Participants were heavy-drinking undergraduate students (N = 207) who completed self-report questionnaires. RESULTS: For men and women, depression predicted overall general health and mental health ratings. For women, depression predicted number of days of role limitations due to poor physical or mental health and number of days of not getting enough sleep or rest. CONCLUSIONS: Findings suggest that depression may have a more pervasive association with HRQOL than alcohol misuse or alcohol-related consequences in college students. Language: en

This paper considers a new class of heteroskedasticity and autocorrelation consistent (HAC) covariance matrix estimators. The estimators considered are prewhitened kernel estimators with vector autoregressions employed in the prewhitening stage. The paper establishes consistency, rate of convergence, and asymptotic truncated mean squared error (MSE) results for the estimators when a fixed or automatic bandwidth procedure is employed. Conditions are obtained under which prewhitening improves asymptotic truncated MSE. Monte Carlo results show that prewhitening is very effective in reducing bias, improving confidence interval coverage probabilities, and rescuing over-rejection of t-statistics constructed using kernel-HAC estimators. On the other hand, prewhitening is found to inflate variance and MSE of the kernel estimators. Since confidence interval coverage probabilities and over-rejection of t-statistics are usually of primary concern, prewhitened kernel estimators provide a significant improvement over the standard non-prewhitened kernel estimators.