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Purpose: We sought to gather perspectives of veterans with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) regarding suicide risk factors, warning signs, and protective factors. We also aimed to modify an existing Veterans Health Administration tool, the Suicide Risk Assessment Guide Pocket Card, for HIV/AIDS provider use. Methods: Twenty male veterans participated in audio-recorded semistructured interviews that were transcribed and coded for themes. Findings: Veterans highlighted personally relevant psychosocial stressors (i.e., poverty, social isolation and loneliness, and physical health). Although the concept of warning signs did not seem salient to participants, they named indicators of elevated imminent risk for self-directed violence (i.e., “relapse,” “not take’n medications,” and “miss’n appointments”) and few protective factors. No themes emerged regarding recommended pocket card changes. Conclusions: This sample of veterans identified self-directed violence risks noted in the general population and others with HIV/AIDS, as well as proximal events associated with increased risk. Care providers are encouraged to explore the relevance of noted imminent and persistent indicators of increased risk with veterans seeking care. [ABSTRACT FROM AUTHOR]

Objective: Examine sleep-wake disturbance (SWD) characteristics, factors, consequences, and management strategies from the perspective of veterans with chronic stage, moderate/severe traumatic brain injury (TBI). Setting: VA Medical Center, Rocky Mountain. US Participants: Nineteen male veterans with post-acute TBI and SWD in the VA Health Administration. Design: Qualitative descriptive. Measures: Semistructured interviews, Ohio State University TBI-Identification Method, Insomnia Severity Index. Results: Two main dimensions emerged: "Messed up sleep" and Surviving and Managing SWD. Sleep-wake disturbance has long-term multidimensional features, etiology, consequences, and practice implications. Although SWD may not be consistently discussed with providers, the problem appears to be pervasive in many aspects of the lives of the informants. Difficulty falling asleep, frequent awakenings, and poor sleep quality were common symptoms that were described as intrusive, isolating, and difficult to self-manage. Veterans discussed a host of physical symptoms, mental health issues, environmental, and behavioral factors that contributed to SWD. Medications, sleep apnea treatment, and self-imposed isolation were frequent management strategies. Veterans expressed a willingness to try new approaches and work with providers. Conclusion: Sleep-wake disturbance among veterans with chronic stage TBI is a multidimensional phenomenon with interplay between comorbidities, contributing factors, effects on functioning, and sleep management strategies. Implications for practice include early and routine evaluation, monitoring, and treatment of SWD. Research is needed to test interventions that address SWD and common TBI comorbidities. [ABSTRACT FROM AUTHOR]

Background: Ab initio many-body methods have been developed over the past 10 yr to address closed-shell nuclei up to mass A≈130 on the basis of realistic two- and three-nucleon interactions. A current frontier relates to the extension of those many-body methods to the description of open-shell nuclei. Several routes to address open-shell nuclei are currently under investigation, including ideas that exploit spontaneous symmetry breaking. Purpose: Singly open-shell nuclei can be efficiently described via the sole breaking of U(1) gauge symmetry associated with particle-number conservation as a way to account for their superfluid character. While this route was recently followed within the framework of self-consistent Green's function theory, the goal of the present work is to formulate a similar extension within the framework of coupled cluster theory. Methods: We formulate and apply Bogoliubov coupled cluster (BCC) theory, which consists of representing the exact ground-state wave function of the system as the exponential of a quasiparticle excitation cluster operator acting on a Bogoliubov reference state. Equations for the ground-state energy and the cluster amplitudes are derived at the singles and doubles level (BCCSD) both algebraically and diagrammatically. The formalism includes three-nucleon forces at the normal-ordered two-body level. The first BCC code is implemented in m scheme, which will permit the treatment of doubly open-shell nuclei via the further breaking of SU(2) symmetry associated with angular momentum conservation. Results: Proof-of-principle calculations in an Nmax = 6 spherical harmonic oscillator basis for 16,18O and 18Ne in the BCCD approximation are in good agreement with standard coupled cluster results with the same chiral two-nucleon interaction, while 20O and 20Mg display underbinding relative to experiment. The breaking of U(1) symmetry, monitored by computing the variance associated with the particle-number operator, is relatively constant for all five nuclei, in both the Hartree-Fock-Bogoliubov and BCCD approximations. Conclusions: The newly developed many-body formalism increases the potential span of ab initio calculations based on single-reference coupled cluster techniques tremendously, i.e., potentially to reach several hundred additional midmass nuclei. The new formalism offers a wealth of potential applications and further extensions dedicated to the description of ground and excited states of open-shell nuclei. Short-term goals include the implementation of three-nucleon forces at the normal-ordered two-body level. Midterm extensions include the approximate treatment of triples corrections and the development of the equation-of-motion methodology to treat both excited states and odd nuclei. Long-term extensions include exact restoration of U(1) and SU(2) symmetries. [ABSTRACT FROM AUTHOR]

Primary objective: To conduct a cross-cultural adaptation of Window to Hope (WtoH), a treatment to reduce hopelessness after traumatic brain injury (TBI), from the Australian civilian context to that of US Veterans. Research design: Three-stage mixed-methods approach. Methods: Stage 1: Consensus conference with stakeholders to revise the manual. Stage 2: Pilot study of the revised manual with US Veterans to examine acceptability, feasibility and fidelity. Stage 3: Review of results with consensus conference attendees and further revisions. Results: Stage 1: Conference attendees reached 100% consensus regarding changes made to the manual. Stage 2: Qualitative results yielded themes that suggest that participants benefitted from the intervention and that multiple factors contributed to successful implementation (Narrative Evaluation of Intervention Interview, User Feedback Survey-Modified, Post-Treatment Interviews). Therapists achieved 100% treatment fidelity. Quantitative results from the Client Satisfaction Questionnaire-8 suggest that the intervention was acceptable. Stage 3: The culturally adapted manual was finalized. Conclusions: Results of this study suggest that the revised WtoH manual is acceptable and feasible. US therapists exhibited adherence to the protocol. The three-stage methodology was successfully employed to cross-culturally adapt an intervention that is well-suited for a Phase II randomized controlled trial among US military Veterans. [ABSTRACT FROM AUTHOR]

For the A = 32, T = 2 quintet we provide a unified theoretical description for three related aspects of isospin mixing: the necessity of more than three terms in the isobaric mass multiplet equation, isospin-torbidden proton decay in 32Cl, and a correction to the allowed Fermi β+ decay of 32Ar. We demonstrate that all three effects observed in experiment can be traced to a common origin related to isospin mixing of the T = 2 states with T = 1 states. [ABSTRACT FROM AUTHOR]

Neutron-rich isotopes in the sdpf space with Z⩽14 require modifications to derived effective interactions to agree with experimental data away from stability. A quantitative justification is given for these modifications because of the weakly bound nature of model space orbits via a procedure using realistic radial wave functions and realistic NN interactions. The long tail of the radial wave function for loosely bound single-particle orbits causes a reduction in the size of matrix elements involving those orbits, most notably for pairing matrix elements, resulting in a more condensed level spacing in shell-model calculations. Example calculations are shown for 36Si and 38Si. [ABSTRACT FROM AUTHOR]

Abstract: A new method for constructing a Hamiltonian for configuration interaction calculations with constraints to energies of spherical configurations obtained with energy-density-functional (EDF) methods is presented. This results in a unified model that reproduced the EDF binding-energy in the limit of single-Slater determinants, but can also be used for obtaining energy spectra and correlation energies with renormalized nucleon–nucleon interactions. The three-body and/or density-dependent terms that are necessary for good nuclear saturation properties are contained in the EDF. Applications to binding-energies and spectra of nuclei in the region above 208Pb are given. [ABSTRACT FROM AUTHOR]

Objective Traumatic brain injury (TBI) is a serious public health concern. Furthermore, inmates and probationers are at a higher risk for TBI, as well as mental health issues and sleepiness. Both sleep and mood disturbance have been linked to poor cognitive performance. These state-dependent cognitive changes can undermine the evaluation of true cognitive ability and contaminate validity. This study examined the effects of sleep and mood on neurocognitive functioning and its impact on the validity of assessment results. Methods This study looked at retrospective Automated Neuropsychological Assessment Metrics (ANAM) core battery data. The sample included inmates and probationers (n = 419) with a history of TBI. A multiple linear regression was used to examine the relationship between self-reported sleepiness, mood state, and cognitive performance. Results All regression models were statistically significant, with negative mood being the most significant predictor of ANAM throughput scores (p = 0.000). Higher endorsement of negative mood states was related to lower cognitive performance overall (p = 0.003). Sleepiness predicted worse performance on at the end of the battery (p < 0.05), whereas positive mood predicted better performance at the beginning of the battery (p < 0.01). Conslusion The present study confirms that negative mood adversely affects global neurocognitive test performance in a forensic population. Examiners should be aware that sleepiness and mood states have an effect on test performance during even brief cognitive batteries. The current findings suggest that it is imperative to screen and identify sleepiness and negative mood symptoms as they may depress test results and threaten the validity or test interpretations and recommendations. [ABSTRACT FROM AUTHOR]

We have recently extended many-body perturbation theory (MBPT) and coupled-cluster theory performed on top of a Slater determinant breaking rotational symmetry to allow for the restoration of the angular momentum at any truncation order (Duguet 2015 J. Phys. G: Nucl. Part. Phys.42 025107). Following a similar route, we presently extend Bogoliubov MBPT and Bogoliubov coupled cluster theory performed on top of a Bogoliubov reference state breaking global gauge symmetry to allow for the restoration of the particle number at any truncation order. Eventually, formalisms can be merged to handle SU(2) and U(1) symmetries at the same time. The long-term goal relates to the ab initio description of near-degenerate finite quantum systems with an open-shell character. [ABSTRACT FROM AUTHOR]

Background: Resonances with pronounced single-particle characteristics are crucial for quantitative descriptions of exotic nuclei near and beyond the drip lines, and often impact halo formation and nucleon decay processes. Since the majority of nuclei are deformed, the interplay between deformation and orbital structure near threshold can lead to improved descriptions of exotic nuclei. Purpose: Develop a method to study single-particle resonant orbital structure in the Dirac equation with a quadrupole-deformed Woods-Saxon potential. Determine the structure evolution of bound and resonant levels with deformation in this scheme, and examine the impact on halo formation in loosely bound systems, with a focus on the recent halo candidate nucleus 37Mg. Method: Analytical continuation of the coupling constant (ACCC) method is developed on the basis of the Dirac equation with a deformed Woods-Saxon potential. The scalar and vector terms in the deformed potential are determined by the energies of the valence neutron and nearby orbitals, which are extracted from a self-consistent relativistic Hartree-Bogoliubov (RHB) calculation with the PC-PK1 density functional. Results: We compare the energies and widths of resonant orbitals in the recent halo nucleus candidate Mg37 using the ACCC method based on the Dirac coupled-channel equations with those determined from the scattering phase shift (SPS) method. It is found that the results from the two methods agree well for narrow resonances, whereas the SPS method fails for broad resonances. Nilsson levels for bound and resonant orbitals from the ACCC method are calculated over a wide range of deformations and show some decisive hints of halo formation in Mg37. Conclusions: In our ACCC model for deformed potentials in the coupled-channel Dirac equations, the crossing of the configuration 1/2[321] and 5/2[312] orbitals at a deformation of approximately 0.5 enhances the probability to occupy the 1/2[321] orbital coming from 2p3/2 thereby explaining the recent observation of a p-wave one-neutron halo configuration in Mg37. The resonant 1/2[301] configuration plays a crucial role in halo formation in the magnesium isotopes beyond A=40 for a wide range of deformations larger than 0.2. [ABSTRACT FROM AUTHOR]

We present theoretical results for the 25Al(p,γ)26Si resonance-capture rate. The isobaric mass multiplet equation is used to determine the energies and Jπ values of states in 26Si based upon those observed in 26Mg and 26Al together with sd shell calculations for the c coefficients. Three Hamiltonians for the sd shell, USD, USDA and USDB, are used to estimate the theoretical uncertainties in the γ-decay and proton-decay widths that go into the resonance-capture rate. [ABSTRACT FROM AUTHOR]

We extend the ab initio coupled-cluster effective interaction (CCEI) method to open-shell nuclei with protons and neutrons in the valence space and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral effective field theory evolved to a lower cutoff via a similarity renormalization group transformation. We find good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei 20Ne and 24Mg, we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an effective field theory for deformed nuclei, thereby demonstrating that collective phenomena in sd-shell nuclei emerge from complex ab initio calculations. [ABSTRACT FROM AUTHOR]

We derive and compute effective valence-space shell-model interactions from ab initio coupled-cluster theory and apply them to open-shell and neutron-rich oxygen and carbon isotopes. Our shell-model interactions are based on nucleon-nucleon and three-nucleon forces from chiral effective-field theory. We compute the energies of ground and low-lying states, and find good agreement with experiment. In particular, our computed 2+ states are consistent with N = 14,16 shell closures in 22,24O, and a weaker N = 14 shell closure in 20C. We find good agreement between our coupled-cluster effective-interaction results with those obtained from standard single-reference coupled-cluster calculations for up to eight valence neutrons. [ABSTRACT FROM AUTHOR]

Background: The self-conjugate nuclei of the A ~ 70 mass region display rapid shape evolution over isotopic or isotonic chains. Shape coexistence has been observed in Se and Kr isotopes reflecting the existence of deformed subshell gaps corresponding to different shell configurations. As and Ge isotopes are located halfway between such deformed nuclei and the Z = 28 shell closure. Purpose: The present work aims at clarifying the low-lying spectroscopy of 66Ge and i,7As, and providing a better insight into the evolution of collectivity in light even-even Ge and even-odd As isotopes Methods: We investigate the low-lying levels and collectivity of the neutron deficient 67As and 66Ge through intermediate-energy Coulomb excitation, inelastic scattering, and proton knockout measurements. The experiment was performed using a cocktail beam of 68Se, 67As, and 66Ge nuclei at an energy of 70-80 MeV/nucleon. Spectroscopic properties of the low-lying states are compared to those calculated via shell model with the JUN45 interaction and beyond-mean-field calculations with the five-dimensional collective Hamiltonian method implemented using the Gogny DIS interaction. The structure evolution of the lower-mass Ge and As isotopes is discussed. Results: Reduced electric quadrupole transition probabilities B(E2) have been extracted from the Coulomb-excitation cross sections measured in 66Ge and 67As. The value obtained for the B(E2;01+ → 21+) in 66Cie is in agreement with a recent measurement, ruling out the existence of a minimum at N = 34 in the B(E2) systematics as previously observed. New transitions have been found in 67As and were assigned to the decay of low-lying negative-parity states. [ABSTRACT FROM AUTHOR]

We report on the single neutron and proton removal reactions from unstable nuclei with large asymmetry &Dgr;S = Sn -- Sp at incident energies below 80 MeV/nucleon. Strong nonsudden effects are observed in the case of deeply-bound-nucleon removal. The corresponding parallel momentum distributions exhibit an abrupt cutoff at high momentum that corresponds to an energy threshold occurring when the incident energy per particle is of comparable magnitude to the nucleón separation energy. A large low-momentum tail is related to both dissipative processes and the dynamics of the nucleón removal process. New limits for the applicability of the sudden and eikonal approximations in nucleón knockout are given. [ABSTRACT FROM AUTHOR]

We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller (&Dgr;L = 0, &Dgr;S = 1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N = 8 shell gap. We populated the ground and 2.24 MeV 0+ states in 12Be using the 12B(1+) (7Li, 7Be) reaction at 80 MeV/u in inverse kinematics. Using the ground-state 5(GT) value from ß-decay measurements (0.184 ± 0.007) as a calibration, the B(GT) for the transition to the second 0+ state was determined to be 0.214 ±0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0+ states in 12Be are composed of 25 ± 5% and 60 ± 5% (0s)4(0p)8 configurations, respectively. [ABSTRACT FROM AUTHOR]

Single nucleon pickup reactions were performed with a 18.1 MeV/nucleon (14)O beam on a deuterium target. Within the coupled reaction channel framework, the measured cross sections were compared to theoretical predictions and analyzed using both phenomenological and microscopic overlap functions. The missing strength due to correlations does not show significant dependence on the nucleon separation energy asymmetry over a wide range of 37 MeV, in contrast with nucleon removal data analyzed within the sudden-eikonal formalism.

We report on the first successful extraction of a β+ Gamow-Teller strength distribution from a radioactive isotope in an intermediate-energy charge-exchange experiment in inverse kinematics. The (7Li,7Be+γ(429  keV)) reaction at 100A  MeV was used to measure Gamow-Teller transition strengths from 34P to states in 34Si. The results show that little mixing occurs between sd and pf shell configurations for the low-lying 0+ and 2+ states even though 34Si neighbors the island of inversion and low-lying 2ℏω intruder states exist. Shell-model calculations in the sdpf model space are consistent with these findings.

Spectroscopic factors have been extracted for proton-rich 34Ar and neutron-rich 46Ar using the (p, d) neutron transfer reaction. The experimental results show little reduction of the ground state neutron spectroscopic factor of the proton-rich nucleus 34Ar compared to that of 46Ar. The results suggest that correlations, which generally reduce such spectroscopic factors, do not depend strongly on the neutron-proton asymmetry of the nucleus in this isotopic region as was reported in knockout reactions. The present results are consistent with results from systematic studies of transfer reactions but inconsistent with the trends observed in knockout reaction measurements.