ACCIDENTAL DROP OF A CARBON STEEL/LEAD SHIPPING CASK AT LOW TEMPERATURES

A shielded cask is used to transport radioactive materials between facilities. The cask was fabricated with an outer and inner shell of hot rolled low carbon steel. Lead was poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to lowtemperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 6 ft assuming brittle failure of the cask shell at subzero temperatures. Finite element models of the cask and its contents were solved and post processed using ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and components and but no complete penetration of the cask shielding. The cask payload outer waste can will experience some permanent plastic deformation in each drop, but will not be deformed to the point where it will rupture, thus maintaining confinement of the can contents

Self-Reported Barriers of Middle-Aged and Older Adults Entering a Home-Based Physical Activity Program

The purpose of this study was to assess barriers experienced by mid-older adults upon entering a homebased, telephone-delivered physical activity (PA) program and examine differences in barriers for subgroups. Methods: Three hundred eighty four participants recruited from Tennessee, California, and Illinois for the Active Choices program, which was part of Active for Life®, completed one face-to-face counseling session and received follow-up telephone counseling. Barriers were analyzed qualitatively and quantitatively for subgroups of mid-older adults. Results: Personal, social, and environmental themes emerged as barriers. Lack of motivation was most salient for men while health barriers were more prominent for women; however, no significant differences were found between men and women. Both whites and African Americans reported lack of motivation as the most frequent barrier to PA. Health and weather barriers were more prominent for the oldest group of older adults. Few differences were reported by PA or weight status. Conclusions: In a large sample of mid-older adults varying in age, race, gender, and health status, multiple barriers to PA were reported. Differences across subgroups may have implications for future PA interventions

Effects of Moderate Sleep Restriction During 8-week Calorie Restriction on Lipoprotein Particles and Glucose Metabolism

Study Objectives This study examined how glucose, glucose regulatory hormones, insulin sensitivity, and lipoprotein subclass particle concentrations and sizes change with sleep restriction during weight loss elicited by calorie restriction. Methods Overweight or obese adults were randomized into an 8-week calorie restriction intervention alone (CR, n = 12; 75% female; body mass index = 31.4 ± 2.9 kg/m2) or combined with sleep restriction (CR+SR, n = 16; 75% female; body mass index = 34.5 ± 3.1 kg/m2). Participants in both groups were given the same instructions to reduce calorie intake. Those in the CR+SR group were instructed to reduce their habitual time-in-bed by 30–90 minutes 5 days each week with 2 ad libitum sleep days. Fasting venous blood samples were collected at pre- and post-intervention. Results Differential changes were found between the two groups (p = 0.028 for group × time interaction) in glucagon concentration, which decreased in the CR group (p = 0.016) but did not change in CR+SR group. Although changes in mean HDL particle (HDL-P) size and visfatin concentration were not statistically different between groups (p = 0.066 and 0.066 for group×time interaction, respectively), mean HDL-P size decreased only in the CR+SR group (Cohen’s d = 0.50, p = 0.022); visfatin concentrations did not change significantly in either group but appeared to decrease in the CR group (Cohen’s d = 0.67, p = 0.170) but not in the CR+SR group (Cohen’s d = 0.43, p = 0.225). Conclusion These results suggest that moderate sleep restriction, despite the presence of periodic ad libitum sleep, influences lipoprotein subclass particles and glucose regulation in individuals undergoing calorie restriction. Clinical trial registration: ClinicalTrials.gov (NCT02413866, Weight Outlooks by Restriction of Diet and Sleep

Aerobic and resistance training improves mood state among adults living with HIV.

The purpose of this investigation was to examine the effects of combined aerobic and resistance exercise training among self-reported mood disturbances, perceived stress, frequency of self-reported symptoms, and symptom distress in a sample of HIV+ adults. For this purpose, 49 participants were randomly assigned into an exercise (EX) or control (CON) group. Those in the EX group completed 50 min of supervised aerobic and resistance training at a moderate intensity twice a week for 6 weeks. The CON group reported to the university and engaged in sedentary activities. Data were collected at baseline before randomization and 6 weeks post intervention. Measures included the symptom distress scale (SDS), perceived stress scale (PSS), profile of mood states (POMS) total score, and the POMS sub-scale for depression and fatigue. A 2 way ANOVA was used to compare between and within group interactions. The EX group showed a significant decrease in reported depression scores (p=0.03) and total POMS (p=0.003). The CON group reported no change in POMS or SDS, but showed a significant increase in PSS. These findings indicate that combination aerobic and resistance training completed at a moderate intensity at least twice a week provides additional psychological benefits independent of disease status and related symptoms

Moderate-Intensity Exercise Improves Body Composition and Improves Physiological Markers of Stress in HIV-Infected Men

HIV/AIDS and its treatment often alter body composition and result in poorer physical functioning. The aim of this study was to determine the effects of a moderate-intensity exercise program on body composition and the hormones and cytokines associated with adverse health outcomes. HIV-infected males (N = 111) were randomized to an exercise group (EX) who completed 6 weeks of moderate-intensity exercise training, or to a nonintervention control group (CON). In pre- and postintervention, body composition was estimated via DXA, peak strength was assessed, and resting blood samples were obtained. There was a decrease in salivary cortisol at wake (P = 0.025) in the EX and a trend (P = 0.07) for a decrease 1 hour after waking. The EX had a significant increase in lean tissue mass (LTM) (P \u3c 0.001) following the intervention. Those in the EX below median body fat (20%) increased LTM (P = 0.014) only, while those above 20% decreased fat mass (P = 0.02), total fat (N = 0.009), and trunk fat (P = 0.001), while also increasing LTM (P = 0.027). Peak strength increased between 14% and 28% on all exercises in the EX group. These data indicate that 6 weeks of moderate-intensity exercise training can decrease salivary cortisol levels, improve physical performance, and improve body composition in HIV-infected men

The Effects of Green Exercise on Physical and Mental Wellbeing: A Systematic Review

We aimed to examine the evidence for the proposed additive effect of exercise in the presence of nature (green exercise) by systematically reviewing studies that investigated the effects of outdoor or virtual green exercise compared with indoor exercise. Our review updates an earlier review, whose searches were conducted in April 2010. Trials were eligible if: (a) participants in an outdoor or virtual exercise condition were exposed to views of nature (green exercise); (b) green exercise was compared with indoor exercise with no exposure to nature; (c) included an outcome related to physical or mental health; (d) used comparative or crossover trial design. We searched the following databases from 1st January 2010 to 28th June 2018: PubMed, CENTRAL, EMBASE, PsycINFO, GreenFile, and Sports DISCUS. We assessed risk of bias using the Cochrane “risk of bias” tool. Where possible we conducted a meta-analysis using the inverse variance random-effects method, and where this approach was not possible we presented the results qualitatively and in harvest plots. We identified 28 eligible trials. In a meta-analysis of just three longitudinal trials, the only statistical finding was slightly lower post-intervention perceived exertion with green versus indoor exercise (mean difference: −1.02; 95 confidence intervals: −1.88, −0.16). Compared with indoor exercise, acute bouts of outdoor green exercise may favorably influence affective valence and enjoyment, but not emotion, perceived exertion, exercise intensity, and biological markers. No other consistent statistical differences were observed, apart from a higher enjoyment of outdoor green versus virtual green exercise. We found a high risk of bias across trials and an overall low quality of evidence. In conclusion, there was limited evidence to support the view that green exercise offers superior benefits to exercise without exposure to nature. The low quality of evidence prohibits clear interpretation of trial findings. Future robust and rigorously designed trials are needed to evaluate the effects of long-term and multiple-bout exposure to nature during exercise compared with exercise indoors

Effect of Exercise Training on Lipoprotein Subclass Particle Concentrations and Sizes in Older Women: Results From a Randomized Controlled Trial

Background: Evidence suggests that lipoprotein subclass particles are critical markers of cardiovascular disease (CVD) risk. Older women have increased CVD risk related to age. The purpose of this study was to determine whether low and moderate doses of exercise influence lipoprotein subclasses. Methods: Women (60–75 years) were randomized into groups for 16 weeks of moderate-intensity exercise training at a low or moderate dose (33.6 and 58.8 kJ/kg body weight weekly, respectively). Lipoprotein subclasses were determined by nuclear magnetic resonance spectroscopy before and after the training. RESULTS: The average weekly exercise duration was 109 and 164 min, for low- and moderate-dose groups, respectively. In the low-dose group, highdensity lipoprotein particle (HDL-P) concentration decreased (∆ = −1.9 ± 3.1 µmol/L, mean ± SD, p = 0.002) and mean HDL-P size increased (∆ = 0.1 ± 0.3 nm, p = 0.028). In the moderate-dose group, mean HDL-P size (∆ = 0.1 ± 0.2 nm; p = 0.024) and low-density lipoprotein particle size increased (∆ = 0.4 ± 3.9 nm; p = 0.007). Baseline body mass index, peak oxygen consumption and age were associated with changes in a few lipoprotein subclasses. Conclusions: In this sample of inactive older women, moderate-intensity exercise training at a dose equivalent to or even lower than the minimally recommended level by public health agencies induced changes in lipoprotein subclasses in line with reduced CVD risk. However, higher doses are encouraged for greater health benefits