Management of Agitation During the COVID-19 Pandemic

The coronavirus disease 2019 (COVID-19) pandemic caused by the coronavirus SARS-CoV-2 has radically altered delivery of care in emergency settings. Unprecedented hardship due to ongoing fears of exposure and threats to personal safety, along with societal measures enacted to curb disease transmission, have had broad psychosocial impact on patients and healthcare workers alike. These changes can significantly affect diagnosing and managing behavioral emergencies such as agitation in the emergency department. On behalf of the American Association for Emergency Psychiatry, we highlight unique considerations for patients with severe behavioral symptoms and staff members managing symptoms of agitation during COVID-19. Early detection and treatment of agitation, precautions to minimize staff hazards, coordination with security personnel and psychiatric services, and avoidance of coercive strategies that cause respiratory depression will help mitigate heightened risks to safety caused by this outbreak

Stressing Out About the Heart: A Narrative Review of the Role of Psychological Stress in Acute Cardiovascular Events

Objectives: Survivors of acute cardiovascular disease (CVD) events, such as acute coronary syndrome (ACS) and stroke, may experience significant psychological distress during and following the acute event. Long-term adverse effects may follow, including the development of posttraumatic stress disorder (PTSD), increased overall all-cause mortality, and recurrent cardiac events. The goal of this concepts paper is to describe and summarize the rates of adverse psychological outcomes, such as PTSD, following cardiovascular emergencies, to review how these psychological factors are associated with increased risk of future events and long-term health and to provide a theoretical framework for future work. Methods: A panel of two board-certified emergency physicians, one with a doctorate in experimental psychology, along with one PhD clinical psychologist with expertise in psychoneuroendocrinology were co-authors involved in the paper. Each author used various search strategies (e.g., PubMed, Psycinfo, Cochrane, and Google Scholar) for primary research and reviewed articles related to their section. The references were reviewed and evaluated for relevancy and included based on review by the lead authors RESULTS: A meta-analysis of 24 studies (N > 2,300) found the prevalence of ACS-induced PTSD at nearly 12%, while a meta-analysis of nine studies (N = 1,138) found that 25% of survivors of transient ischemic attack and stroke report PTSD symptoms. The presence of PTSD doubles 3-year risk of CVD/mortality risk in ACS survivors. Cardiac patients treated during periods of ED overcrowding, hallway care, and perceived poor clinician-patient communication appear at greater risk for subsequent PTSD. Conclusions: Psychological stress is often present in patients undergoing evaluation for acute CVD events. Understanding such associations provides a foundation to appreciate the potential contribution of psychological variables on acute and long-term cardiovascular recovery, while also stimulating future areas of research and discovery

Nucleon axial and pseudoscalar form factors from the covariant Faddeev equation

We compute the axial and pseudoscalar form factors of the nucleon in the Dyson-Schwinger approach. To this end, we solve a covariant three-body Faddeev equation for the nucleon wave function and determine the matrix elements of the axialvector and pseudoscalar isotriplet currents. Our only input is a well-established and phenomenologically successful ansatz for the nonperturbative quark-gluon interaction. As a consequence of the axial Ward-Takahashi identity that is respected at the quark level, the Goldberger-Treiman relation is reproduced for all current-quark masses. We discuss the timelike pole structure of the quark-antiquark vertices that enters the nucleon matrix elements and determines the momentum dependence of the form factors. Our result for the axial charge underestimates the experimental value by 20-25% which might be a signal of missing pion-cloud contributions. The axial and pseudoscalar form factors agree with phenomenological and lattice data in the momentum range above Q^2 ~ 1...2 GeV^2.Comment: 17 pages, 7 figures, 1 tabl

Chiral Symmetry Breaking and Pion Wave Function

We consider here chiral symmetry breaking through nontrivial vacuum structure with quark antiquark condensates. We then relate the condensate function to the wave function of pion as a Goldstone mode. This simultaneously yields the pion also as a quark antiquark bound state as a localised zero mode in vacuum. We illustrate the above with Nambu Jona-Lasinio model to calculate different pionic properties in terms of the vacuum structure for breaking of exact or approximate chiral symmetry, as well as the condensate fluctuations giving rise to $\sigma$ mesons.Comment: latex, revtex, 16 page

Perturbation Theory with a Variational Basis: the Generalized Gaussian Effective Potential

The perturbation theory with a variational basis is constructed and analyzed.The generalized Gaussian effective potential is introduced and evaluated up to the second order for selfinteracting scalar fields in one and two spatial dimensions. The problem of the renormalization of the mass is discussed in details. Thermal corrections are incorporated. The comparison between the finite temperature generalized Gaussian effective potential and the finite temperature effective potential is critically analyzed. The phenomenon of the restoration at high temperature of the symmetry broken at zero temperature is discussed.Comment: RevTex, 49 pages, 16 eps figure

Transition Form Factors between Pseudoscalar and Vector Mesons in Light-Front Dynamics

We study the transition form factors between pseudoscalar and vector mesons using a covariant fermion field theory model in $(3+1)$ dimensions. Performing the light-front calculation in the $q^+ =0$ frame in parallel with the manifestly covariant calculation, we note that the suspected nonvanishing zero-mode contribution to the light-front current $J^+$ does not exist in our analysis of transition form factors. We also perform the light-front calculation in a purely longitudinal $q^+ > 0$ frame and confirm that the form factors obtained directly from the timelike region are identical to the ones obtained by the analytic continuation from the spacelike region. Our results for the $B \to D^* l \nu_l$ decay process satisfy the constraints on the heavy-to-heavy semileptonic decays imposed by the flavor independence in the heavy quark limit.Comment: 20 pages, 14 figure

Short-distance matrix elements for D0-meson mixing from Nf=2+1 lattice QCD

We calculate in three-flavor lattice QCD the short-distance hadronic matrix elements of all five ΔC=2 four-fermion operators that contribute to neutral D-meson mixing both in and beyond the Standard Model. We use the MILC Collaboration’s Nf=2+1 lattice gauge-field configurations generated with asqtad-improved staggered sea quarks. We also employ the asqtad action for the valence light quarks and use the clover action with the Fermilab interpretation for the charm quark. We analyze a large set of ensembles with pions as light as lattice gauge-field configurations generated with asqtad-improved staggered sea quarks. We also employ the asqtad action for the valence light quarks and use the clover action with the Fermilab interpretation for the charm quark. We analyze a large set of ensembles with pions as light as Mπ ≈ 180 MeV and lattice spacings as fine as a ≈ 0.045 fm, thereby enabling good control over the extrapolation to the physical pion mass and continuum limit. We obtain for the matrix elements in the MS−NDR scheme using the choice of evanescent operators proposed by Beneke et al., evaluated at 3 GeV, ⟨D0|Oi|¯D0⟩ = {0.0805(55)16),−0.1561(70)(31), 0.0464(31)(9), 0.2747(129)(55), 0.1035(71)(21)} GeV4 (i=1–5). The errors shown are from statistics and lattice systematics, and the omission of charmed sea quarks, respectively. To illustrate the utility of our matrix-element results, we place bounds on the scale of CP-violating new physics in D0 mixing, finding lower limits of about 10–50×103 TeV for couplings of O(1). To enable our results to be employed in more sophisticated or model-specific phenomenological studies, we provide the correlations among our matrix-element results. For convenience, we also present numerical results in the other commonly used scheme of Buras, Misiak, and Urban

Gold-plated Mode of CP-Violation in Decays of B_c Meson from QCD Sum Rules

The model-independent method based on the triangle ideology is implemented to extract the CKM-matrix angle gamma in the decays of doubly heavy long-lived meson B_c. We analyze a color structure of diagrams and conditions to reconstruct two reference-triangles by tagging the flavor and CP eigenstates of D^0 meson in the fixed exclusive channels. The characteristic branching ratios are evaluated in the framework of QCD sum rules.Comment: 11 pages, RevTeX4 file, 4 eps-figure

Updated resonance photo-decay amplitudes to 2 GeV

We present the results of an energy-dependent and set of single-energy partial-wave analyses of single-pion photoproduction data. These analyses extend from threshold to 2 GeV in the laboratory photon energy, and update our previous analyses to 1.8 GeV. Photo-decay amplitudes are extracted for the baryon resonances within this energy range. We consider two photoproduction sum rules and the contributions of two additional resonance candidates found in our most recent analysis of $\pi N$ elastic scattering data. Comparisons are made with previous analyses.Comment: Revtex, 26 pages, 3 figures. Postscript figures available from ftp://clsaid.phys.vt.edu/pub/pr or indirectly from http://clsaid.phys.vt.edu/~CAPS

B(s)0B^0_{(s)}-mixing matrix elements from lattice QCD for the Standard Model and beyond

We calculate---for the first time in three-flavor lattice QCD---the hadronic matrix elements of all five local operators that contribute to neutral $B^0$- and $B_s$-meson mixing in and beyond the Standard Model. We present a complete error budget for each matrix element and also provide the full set of correlations among the matrix elements. We also present the corresponding bag parameters and their correlations, as well as specific combinations of the mixing matrix elements that enter the expression for the neutral $B$-meson width difference. We obtain the most precise determination to date of the SU(3)-breaking ratio $\xi = 1.206(18)(6)$, where the second error stems from the omission of charm sea quarks, while the first encompasses all other uncertainties. The threefold reduction in total uncertainty, relative to the 2013 Flavor Lattice Averaging Group results, tightens the constraint from $B$ mixing on the Cabibbo-Kobayashi-Maskawa (CKM) unitarity triangle. Our calculation employs gauge-field ensembles generated by the MILC Collaboration with four lattice spacings and pion masses close to the physical value. We use the asqtad-improved staggered action for the light valence quarks, and the Fermilab method for the bottom quark. We use heavy-light meson chiral perturbation theory modified to include lattice-spacing effects to extrapolate the five matrix elements to the physical point. We combine our results with experimental measurements of the neutral $B$-meson oscillation frequencies to determine the CKM matrix elements $|V_{td}| = 8.00(34)(8) \times 10^{-3}$, $|V_{ts}| = 39.0(1.2)(0.4) \times 10^{-3}$, and $|V_{td}/V_{ts}| = 0.2052(31)(10)$, which differ from CKM-unitarity expectations by about 2$\sigma$. These results and others from flavor-changing-neutral currents point towards an emerging tension between weak processes that are mediated at the loop and tree levels.Comment: 75 pp, 17 figs. Ver 2 fixes typos; corrects mistakes resulting in slight changes to results, correlation matrices; updates decay constants to agree with recent PDG update; corrects uncertainties for tree-level CKM matrix elements used in comparison, slightly reducing tensions; includes additional analyses that support mostly-nonperturbative matching; expands discussion of isospin-breaking effect