Search

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 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.

As Veterans from recent conflicts return from deployments, increasing numbers are seeking care for physical (e.g., history of traumatic brain injury) and mental health (e.g., depression, anxiety) symptoms. Data suggest that only about half of recent Veterans are seeking care within the Veterans Health Administration. As such, providers within the community are likely to require additional training to meet the unique needs of these Veterans and their families. Towards this end, meetings were held with administrators and clinicians at Colorado Community Mental Health Centers (CMHCs) to identify current barriers and facilitators, as they relate to working with Veterans with a history of TBI and co-occurring mental health conditions. On-whole, CMHC employees had limited experience with providing care to the cohort of interest. Additional training will assist with increasing capacity and a web-based toolkit was developed to facilitate the transfer of knowledge ( www.mirecc.va.gov/visn19/tbi_toolkit ).

Objective To evaluate the efficacy of a psychological intervention to reduce moderate to severe hopelessness among Veterans with moderate to severe traumatic brain injury (TBI). Design Two-arm parallel group, controlled, randomized crossover trial, with 3-month follow-up for those initially allocated to treatment. Participants were randomly allocated in blocks of 4 on a 1:1 ratio to treatment (n = 15) or waitlist (n = 20) groups. Setting A Veterans Affairs Medical Center. Participants Veterans between the ages of 26 and 65 years, with a history of moderate to severe TBI, and moderate to severe hopelessness. Interventions A 20-hour manualized small group cognitive-behavioral intervention. Main outcome measures Beck Hopelessness Scale (primary), Beck Depression Inventory, and Beck Scale for Suicide Ideation. Results A significant difference between groups was found for postintervention scores on the Beck Hopelessness Scale (P = .03). Significant decreases were maintained at follow-up. For those initially allocated to the waitlist group who completed the intervention, treatment gains were noted in decreased hopelessness (P = .01) and depression (P = .003). Conclusions Findings from this trial provide additional support for the efficacy of this method of psychological treatment of hopelessness among individuals with moderate to severe TBI.

At TRIUMF, the TIGRESS Integrated Plunger device and its suite of ancillary detector systems have been implemented for charged-particle tagging and light-ion identification in coincidence with $\ensuremath{\gamma}$-ray spectroscopy for Doppler-shift lifetime studies and low-energy Coulomb excitation measurements. As a test of the device, the lifetime of the first ${2}^{+}$ excited state in $^{36}\mathrm{Ar}$ was measured from the $\ensuremath{\gamma}$-ray line shape of the ${2}_{1}^{+}\ensuremath{\rightarrow}{0}_{\mathrm{g}.\mathrm{s}.}^{+}$ transition using the Doppler-shift attenuation technique following Coulomb excitation. The line-shape signatures, vital for precision lifetime measurements, were significantly improved by enhanced reaction-channel selectivity using a complementary approach of kinematic gating and digital rise-time discrimination of recoiling charged particles in a silicon PIN diode array. The lifetime was determined by comparisons between the data and simulated line shapes generated using our TIGRESS Coulomb excitation code as an input to the Lindhard method, which was then extended and included as a class in geant4. The model-independent lifetime result of $490\ifmmode\pm\else\textpm\fi{}50$ fs corresponds to a reduced quadrupole transition strength of $B(E2;{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{\mathrm{g}.\mathrm{s}.}^{+})=56\ifmmode\pm\else\textpm\fi{}6\phantom{\rule{0.28em}{0ex}}{\mathrm{e}}^{2}{\mathrm{fm}}^{4}$ and agrees well with previous intermediate energy Coulomb excitation measurements, thereby resolving reported discrepancies in the ${2}_{1}^{+}$ level lifetime in this self-conjugate nucleus.

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 U.S. Veterans.Three-stage mixed-methods approach.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.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.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.

P. Voss et al. -- 11 pags., 12 figs., 2 tabs., At TRIUMF, the TIGRESS Integrated Plunger device and its suite of ancillary detector systems have been implemented for charged-particle tagging and light-ion identification in coincidence with γ-ray spectroscopy for Doppler-shift lifetime studies and low-energy Coulomb excitation measurements. As a test of the device, the lifetime of the first 2+ excited state in Ar36 was measured from the γ-ray line shape of the 21+→0g.s.+ transition using the Doppler-shift attenuation technique following Coulomb excitation. The line-shape signatures, vital for precision lifetime measurements, were significantly improved by enhanced reaction-channel selectivity using a complementary approach of kinematic gating and digital rise-time discrimination of recoiling charged particles in a silicon PIN diode array. The lifetime was determined by comparisons between the data and simulated line shapes generated using our TIGRESS Coulomb excitation code as an input to the Lindhard method, which was then extended and included as a class in geant4. The model-independent lifetime result of 490±50 fs corresponds to a reduced quadrupole transition strength of B(E2;21+→0g.s.+)=56±6e2fm4 and agrees well with previous intermediate energy Coulomb excitation measurements, thereby resolving reported discrepancies in the 21+ level lifetime in this self-conjugate nucleus., The authors would like to acknowledge the support of the ISAC Operations Group at TRIUMF, the TRIUMF Detectors and Engineering Groups, and the TRIUMF Scintillator Shop as well as the invaluable assistance and expertise of the Simon Fraser University Science Machine and Electronics Shops. This work is supported by the National Sciences and Engineering Research Council of Canada Awards SAPIN/371656-2010 and SAPEQ/390539-2010 and the Simon Fraser University Vice President, Research. TRIUMF receives federal funding via a contribution agreement from the National Research Council of Canada.

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. Language: en

We present results for levels in 26Si (the mirror of nucleus 26Si). The calculated gamma decay lifetimes and 25Al to 26Si spectroscopic factors together with experimental information on the levels of excited states will be used to determine the Al 25 ( p , γ ) Si 26 reaction rates together with a theoretical error on this rate based on the use of the USDA and USDB interactions.

The Nuclear Structure Laboratory (NSL) at the University of Notre Dame installed its Browne–Buechner spectrograph in the early 1970s for highly accurate energy measurements of nuclear reactions. Current renovation and upgrading of this spectrograph will enable operation of the magnet in a gas-filled mode, in particular for the study of nuclear reactions with low cross-sections of interest in nuclear astrophysics. One of the principle issues shared by measurements of extremely low abundances in Accelerator Mass Spectrometry (AMS) and nuclear astrophysics is the discrimination between the nuclei of interest and often very intense isobaric background. Recently the AMS technique of the gas-filled magnet has very successfully been used at Argonne National Laboratory (ANL) to overcome this in the study of both environmental noble gas traces ( 39 Ar) and the measurement of cross-sections of interest in stellar nucleosynthesis i.e. the 62 Ni( n , γ) 63 Ni reaction. We hope to extend these techniques further to the observations of astrophysically important reactions such as 40 Ca(α, γ) 44 Ti and 78 Kr(α, γ) 82 Sr.

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.

We extend the ab initio coupled-cluster effective interaction (CCEI) method to deformed 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 $^{20}$Ne and $^{24}$Mg 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.

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 $^{37}\mathrm{Mg}$.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 $^{37}\mathrm{Mg}$ 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 $^{37}\mathrm{Mg}$.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 $2{p}_{3/2}$ thereby explaining the recent observation of a $\mathit{p}$-wave one-neutron halo configuration in $^{37}\mathrm{Mg}$. 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.

Ab initio many-body methods address closed-shell nuclei up to mass A ~ 130 on the basis of realistic two- and three-nucleon interactions. Several routes to address open-shell nuclei are currently under investigation, including ideas which exploit spontaneous symmetry breaking. Singly open-shell nuclei can be efficiently described via the sole breaking of $U(1)$ gauge symmetry associated with particle number conservation, to account for their superfluid character. The present work formulates and applies Bogoliubov coupled cluster (BCC) theory, which consists of representing the exact ground-state wavefunction 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 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 eventually permit the treatment of doubly open-shell nuclei. Proof-of-principle calculations in an $N_{\text{max}}=6$ spherical harmonic oscillator basis are performed for $^{16,18,20}$O, $^{18}$Ne, $^{20}$Mg in the BCCD approximation with a chiral two-nucleon interaction, comparing to results obtained in standard coupled cluster theory when applicable. The breaking of $U(1)$ symmetry is monitored by computing the variance associated with the particle-number operator. 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 mid-mass 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., 22 pages, 13 figures

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 $^{22,24}\mathrm{O}$, and a weaker $N=14$ shell closure in $^{20}\mathrm{C}$. 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.

A complete treatment of the thermal noise in a MOSFET including both drain current noise and induced gate current noise has been developed by deriving a small-signal model valid at high frequencies and for short-channel devices. On the basis of this model the parameters currently used for the representation of a noisy two-port have been derived. As those parameters depend on the noise sources and on the admittance matrix terms, both these contributions have been accurately modeled. Finally, the model has been applied to the derivation of MOSFET two-port noise parameters in order to minimize noise figure of low noise amplifiers.

8 pags. ; 10 figs. ; 1 app. ; PACS number(s): 21.60.De, 21.60.Jz, 24.10.Cn, 21.30.Fe, We present an extension of the pair coupled cluster doubles (p-CCD) method to quasiparticles and apply it to the attractive pairing Hamiltonian. Near the transition point where number symmetry gets spontaneously broken, the proposed BCS-based p-CCD method yields energies significantly better than those of existing methods when compared to the exact results obtained via solution of the Richardson equations. The quasiparticle p-CCD method has a low computational cost of O(N3) as a function of system size. This together with the high quality of results here demonstrated points to considerable promise for the accurate description of strongly correlated systems with more realistic pairing interactions., Spanish MINECO under Grant No. FIS2012-34479.