Structural influence on atomic hopping and electronic states of Pd-based bulk metallic glasses

Atomic motion and electronic structures of Pd–Ni–Cu–P bulk metallic glasses were investigated using 31P nuclear magnetic resonance. The hopping rate of P atoms was determined by the stimulated echo technique. Significant hopping was observed in all alloys well below the glass transition temperature. Increasing the Cu content to above 25 at. % increases P hopping significantly, consistent with the previous finding that the openness of the structure increases with Cu content. In contrast, P hopping is not influenced by changes of local electronic states at P sites, induced by the substitution of Ni by Cu

Sensory functions and their relation to balance metrics: a secondary analysis of the LIMBIC-CENC multicenter cohort

IntroductionAmong patients with traumatic brain injury (TBI), balance problems often persist alongside hearing and vision impairments that lead to poorer outcomes of functional independence. As such, the ability to regain premorbid independent gait may be dictated by the level of sensory acuity or processing decrements that are shown following TBI assessment. This study explores the relationships between standardized sensory acuity and processing outcomes to postural balance and gait speed.MethodsSecondary analysis was performed on the Long-Term Impact of Military- Relevant Brain Injury Consortium Chronic Effects of Neurotrauma Consortium LIMBIC (CENC) data set. Separate regression analyses were carried out for each of the balance assessments (via Computerized Dynamic Posturography, CDP) and walking speed.DiscussionTBI frequency was significantly related to the majority of single CDP outcomes (i.e., Conditions 2–6), while various sensory processing outcomes had task-specific influences. Hearing impairments and auditory processing decrements presented with lower CDP scores (CDP Conditions 3,5,6, and 1–3 respectively), whereas greater visual processing scores were associated with better CDP scores for Conditions 2,5, and 6. In sum, patients with TBI had similar scores on static balance tests compared to non-TBI, but when the balance task got more difficult patients with TBI scored worse on the balance tests. Additionally, stronger associations with sensory processing than sensory acuity measures may indicate that patients with TBI have increased fall risk

Bostonia: The Boston University Alumni Magazine. Volume 9

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

Headache among combat-exposed veterans and service members and its relation to mild traumatic brain injury history and other factors: a LIMBIC-CENC study

BackgroundHeadache (HA) is a common persistent complaint following mild traumatic brain injury (mTBI), but the association with remote mTBI is not well established, and risk factors are understudied.ObjectiveDetermine the relationship of mTBI history and other factors with HA prevalence and impact among combat-exposed current and former service members (SMs).DesignSecondary cross-sectional data analysis from the Long-Term Impact of Military-Relevant Brain Injury Consortium—Chronic Effects of Neurotrauma Consortium prospective longitudinal study.MethodsWe examined the association of lifetime mTBI history, demographic, military, medical and psychosocial factors with (1) HA prevalence (“lately, have you experienced headaches?”) using logistic regression and (2) HA burden via the Headache Impact Test-6 (HIT-6) using linear regression. Each lifetime mTBI was categorized by mechanism (blast-related or not) and setting (combat deployed or not). Participants with non-credible symptom reporting were excluded, leaving N = 1,685 of whom 81% had positive mTBI histories.ResultsAt a median 10 years since last mTBI, mTBI positive participants had higher HA prevalence (69% overall, 78% if 3 or more mTBIs) and greater HA burden (67% substantial/severe impact) than non-TBI controls (46% prevalence, 54% substantial/severe impact). In covariate-adjusted analysis, HA prevalence was higher with greater number of blast-related mTBIs (OR 1.81; 95% CI 1.48, 2.23), non-blast mTBIs while deployed (OR 1.42; 95% CI 1.14, 1.79), or non-blast mTBIs when not deployed (OR 1.23; 95% CI 1.02, 1.49). HA impact was only higher with blast-related mTBIs. Female identity, younger age, PTSD symptoms, and subjective sleep quality showed effects in both prevalence and impact models, with the largest mean HIT-6 elevation for PTSD symptoms. Additionally, combat deployment duration and depression symptoms were factors for HA prevalence, and Black race and Hispanic/Latino ethnicity were factors for HA impact. In sensitivity analyses, time since last mTBI and early HA onset were both non-significant.ConclusionThe prevalence of HA symptoms among formerly combat-deployed veterans and SMs is higher with more lifetime mTBIs regardless of how remote. Blast-related mTBI raises the risk the most and is uniquely associated with elevated HA burden. Other demographic and potentially modifiable risk factors were identified that may inform clinical care

Characteristics and Outcomes of Adults Hospitalized with SARS-CoV-2 Community-Acquired Pneumonia in Louisville, Kentucky

Background: Patients infected with the novel coronavirus SARS-CoV-2 are frequently hospitalized with community-acquired pneumonia (CAP). The objective of this study was to define the clinical characteristics and outcomes of hospitalized patients with SARS-CoV-2 CAP in the city of Louisville, KY. Methods: This was a retrospective observational study of 700 patients with SARS-CoV-2 infection hospitalized to eight of the adult hospitals in the city of Louisville. Patients with 1) a positive RT-PCR for SARS-CoV-2, 2) fever, cough, or shortness of breath, and 3) an infiltrate at chest imaging were defined as having SARS-CoV-2 CAP. Demographic characteristics of the study population were compared with census data from the city of Louisville. For each patient more than 500 variables were abstracted from electronic medical records and recorded using Research Electronic Data Capture software. Data was analyzed by descriptive and inferential statistics using R version 3.4.0. Results: SARS-CoV-2 CAP was identified in 632 (90%) patients hospitalized with COVID-19. The median age of the patients was 63 years, 53% were females, 31% were black and 12% Hispanic. The most frequent comorbidities were hypertension (56%), obesity (50%), and diabetes (33%). Mortality was 17% for the total population and 34% for the 249 patients admitted to ICU. For each category of race, ethnicity and comorbidities, the proportion of hospitalized patients with SARS-CoV-2 CAP was significantly different when compared to the Louisville population (p \u3c 0.001). Conclusion: Patients of black race, Hispanic ethnicity, and patients with history of hypertension, obesity or diabetes are overrepresented among hospitalized patients with SARS-CoV-2 CAP when compared to the Louisville population. Hospitalized patients with SARS-CoV-2 CAP are likely to require ICU care, with death occurring in approximately one of six hospitalizations

No difference in clinical outcomes for African American and White patients hospitalized with SARS-CoV-2 pneumonia in Louisville, Kentucky

Introduction: Current literature indicates that African American individuals are at increased risk of becoming infected with the SARS-CoV-2 virus and suffer higher SARS-CoV-2-related mortality rates. However, there is a lack of consensus as to how the clinical outcomes of African American patients differ from those of other groups. The objective of this study was to define the clinical outcomes of African American and White hospitalized patients with SARS-CoV-2 community-acquired pneumonia (CAP) in Louisville, Kentucky. Methods: This was a retrospective cohort study of hospitalized patients with SARS-CoV-2 CAP at eight hospitals in Louisville, Kentucky. Severity of CAP at time of hospitalization was evaluated using the pneumonia severity index (PSI), CURB-65 score and SARS-CoV-2 viral load. The following thirteen clinical outcomes were compared: discharge alive to home, time to home discharge, admission to the ICU, length of ICU stay, need for invasive mechanical ventilation (IMV), duration of IMV, development of acute respiratory distress syndrome (ARDS), development of septic shock, need for vasopressors, development of cardiovascular events, time to cardiovascular events, in-hospital mortality, and time to death. Results: A total of 541 patients were eligible for this study, 343 White (63%) and 198 African American (37%). None of the thirteen clinical outcomes were statistically significantly different between the two groups. Conclusions: This study indicates that African American and White patients do not have different clinical outcomes after the point of hospitalization due to SARS-CoV-2 CAP

Variability of Disk Emission in Pre-Main Sequence and Related Stars. I. HD 31648 and HD 163296 - Isolated Herbig Ae Stars Driving Herbig-Haro Flows

Infrared photometry and spectroscopy covering a time span of a quarter century are presented for HD 31648 (MWC 480) and HD 163296 (MWC 275). Both are isolated Herbig Ae stars that exhibit signs of active accretion, including driving bipolar flows with embedded Herbig-Haro (HH) objects. HD 163296 was found to be relatively quiescent photometrically in its inner disk region, with the exception of a major increase in emitted flux in a broad wavelength region centered near 3 microns in 2002. In contrast, HD 31648 has exhibited sporadic changes in the entire 3-13 micron region throughout this span of time. In both stars the changes in the 1-5 micron flux indicate structural changes in the region of the disk near the dust sublimation zone, possibly causing its distance from the star to vary with time. Repeated thermal cycling through this region will result in the preferential survival of large grains, and an increase in the degree of crystallinity. The variability observed in these objects has important consequences for the interpretation of other types of observations. For example, source variability will compromise models based on interferometry measurements unless the interferometry observations are accompanied by nearly-simultaneous photometric data.Comment: 55 pages, 18 figures, 2 tables, Accepted by Ap

Age-dependent white matter disruptions after military traumatic brain injury: Multivariate analysis results from ENIGMA brain injury

Mild Traumatic brain injury (mTBI) is a signature wound in military personnel, and repetitive mTBI has been linked to age-related neurogenerative disorders that affect white matter (WM) in the brain. However, findings of injury to specific WM tracts have been variable and inconsistent. This may be due to the heterogeneity of mechanisms, etiology, and comorbid disorders related to mTBI. Non-negative matrix factorization (NMF) is a data-driven approach that detects covarying patterns (components) within high-dimensional data. We applied NMF to diffusion imaging data from military Veterans with and without a self-reported TBI history. NMF identified 12 independent components derived from fractional anisotropy (FA) in a large dataset (n = 1,475) gathered through the ENIGMA (Enhancing Neuroimaging Genetics through Meta-Analysis) Military Brain Injury working group. Regressions were used to examine TBI- and mTBI-related associations in NMF-derived components while adjusting for age, sex, post-traumatic stress disorder, depression, and data acquisition site/scanner. We found significantly stronger age-dependent effects of lower FA in Veterans with TBI than Veterans without in four components (q \u3c 0.05), which are spatially unconstrained by traditionally defined WM tracts. One component, occupying the most peripheral location, exhibited significantly stronger age-dependent differences in Veterans with mTBI. We found NMF to be powerful and effective in detecting covarying patterns of FA associated with mTBI by applying standard parametric regression modeling. Our results highlight patterns of WM alteration that are differentially affected by TBI and mTBI in younger compared to older military Veterans