Validation of THOR Finite Element Model

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Soyuz Occupant Risk

Spaceflight has unique challenges for Occupant Protection. Current NASA Occupant Protection Requirements are based on military and automotive biodynamics research: Brinkley Dynamic Response Criteria; Hybrid III Anthropomorphic Test Device (ATD). Soyuz offers unique insight into the role of spaceflight deconditioning on impact tolerance. Project Objectives: 1. Develop a landing injury database; 2. Obtain seat acceleration data from TMA (Soyuz-TMA: Transport Modified Anthropometric) landings; 3. Re-create Soyuz landings using models; 4. Update NASA occupant protection standards as needed

An ecological approach to understanding academic achievement: Considering intrapersonal, physical activity, and support variables

The purpose of this study was to examine the relation between measures of students’ physical well-being and self-perception and their academic achievement. Specifically, we look at students’ social support for physical activity, physical activity perceptions, self-concept, self-efficacy, health behaviors, and cardiorespiratory fitness (as measured by the PACER test). Students (n = 697 fifth graders) were surveyed at the beginning of the school year. A two-group path analysis revealed notable relationships between the predictor variables and proximal and distal outcomes, with some paths moderated by sex. One relationship that was significant for both sexes was cardiorespiratory fitness, as it was the only significant predictor of achievement. This effect was moderate to large for the female students (R_Math^2 = 36%; R_Read^2 = 15%) and small to large for the male students (R_Math^2 = 26%; R_Read^2 = 10%). These findings can be used to guide future research and educational prevention and intervention efforts

Occupant Protection Project

Topics include occupant protection overview with a focus on crew protection during dynamic phases of flight; occupant protection collaboration; modeling occupant protection; occupant protection considerations; project approach encompassing analysis tools, injury criteria, and testing program development; injury criteria update methodology, unique effects of pressure suits and other factors; and a summary

Rotation in the Pleiades with K2. III. Speculations on origins and evolution

We use high quality K2 light curves for hundreds of stars in the Pleiades to understand better the angular momentum evolution and magnetic dynamos of young, low mass stars. The K2 light curves provide not only rotational periods but also detailed information from the shape of the phased light curve not available in previous studies. A slowly rotating sequence begins at (V−Ks)0 ∼ 1.1 (spectral type F5) and ends at (V−Ks)0 ∼ 3.7 (spectral type K8), with periods rising from ∼2 to ∼11 days in that interval. 52% percent of the Pleiades members in that color interval have periods within 30% of a curve defining the slow sequence; the slowly rotating fraction decreases significantly redward of (V−Ks)0=2.6. Nearly all of the slow-sequence stars show light curves that evolve significantly on timescales less than the K2 campaign duration. The majority of the FGK Pleiades members identified as photometric binaries are relatively rapidly rotating, perhaps because binarity inhibits star-disk angular momentum loss mechanisms during pre-main sequence evolution. The fully convective, late M dwarf Pleiades members (5.0 < (V−Ks)0 < 6.0) nearly always show stable light curves, with little spot evolution or evidence of differential rotation. During PMS evolution from ∼3 Myr (NGC2264 age) to ∼125 Myr (Pleiades age), stars of 0.3 M⊙ shed about half their angular momentum, with the fractional change in period between 3 and 125 Myr being nearly independent of mass for fully convective stars. Our data also suggest that very low mass binaries form with rotation periods more similar to each other and faster than would be true if drawn at random from the parent population of single stars.PostprintPeer reviewe

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Association of serious adverse events with Cheyne-Stokes respiration characteristics in patients with systolic heart failure and central sleep apnoea: A SERVE-Heart Failure substudy analysis

Background and objective Increases in Cheyne-Stokes respiration (CSR) cycle length (CL), lung-to-periphery circulation time (LPCT) and time to peak flow (TTPF) may reflect impaired cardiac function. This retrospective analysis used an automatic algorithm to evaluate baseline CSR-related features and then determined whether these could be used to identify patients with systolic heart failure (HF) who experienced serious adverse events in the Treatment of Sleep-Disordered Breathing with Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients with Heart Failure (SERVE-HF) substudy. Methods A total of 280 patients had overnight diagnostic polysomnography data available; an automated algorithm was applied to quantify CSR-related features. Results Median baseline CL, LPCT and TTPF were similar in the control (n = 152) and adaptive servo-ventilation (ASV, n = 156) groups. In both groups, CSR-related features were significantly longer in patients who did (n = 129) versus did not (n = 140) experience a primary endpoint event (all-cause death, life-saving cardiovascular intervention or unplanned hospitalization for worsening HF): CL, 61.1 versus 55.1 s (P = 0.002); LPCT, 36.5 versus 31.5 s (P < 0.001); TTPF, 15.20 versus 13.35 s (P < 0.001), respectively. This finding was independent of treatment allocation. Conclusion Patients with systolic HF and central sleep apnoea who experienced serious adverse events had longer CSR CL, LPCT and TTPF. Future studies should examine an independent role for CSR-related features to enable risk stratification in systolic HF

Perceptions of Statin Discontinuation among Patients with Life-Limiting Illness

BACKGROUND: Optimal management of chronic medications for patients with life-limiting illness is uncertain. Medication deprescribing may improve outcomes in this population, but patient concerns regarding deprescribing are unclear. OBJECTIVE: The aim of this study was to quantify the perceived benefits and concerns of statin discontinuation among patients with life-limiting illness. DESIGN: Baseline data from a multicenter, pragmatic clinical trial of statin discontinuation were used. SETTING/SUBJECTS: Cognitively intact participants with a life expectancy of 1-12 months receiving statin medications for primary or secondary prevention were enrolled. MEASUREMENTS: Responses to a 9-item questionnaire addressing patient concerns about discontinuing statins were collected. We used Pearson chi-square tests to compare responses by primary life-limiting diagnosis (cancer, cardiovascular disease, other). RESULTS: Of 297 eligible participants, 58% had cancer, 8% had cardiovascular disease, and 30% other primary diagnoses. Mean (standard deviation) age was 72 (11) years. Fewer than 5% of participants expressed concern that statin deprescribing indicated physician abandonment. About one in five participants reported being told to take statins for the rest of their life (18%) or feeling that discontinuation represented prior wasted effort (18%). Many participants reported benefits of stopping statins, including spending less money on medications (63%), potentially stopping other medications (34%), and having a better quality of life (25%). More participants with cardiovascular disease as a primary diagnosis perceived that quality-of-life benefits related to statin discontinuation (52%) than participants with cancer (27%) or noncardiovascular disease diagnoses (27%) [p = 0.034]. CONCLUSION: Few participants expressed concerns about discontinuing statins; many perceived potential benefits. Cardiovascular disease patients perceived greater potential positive impact from statin discontinuation