Credibility intervals in Bayesian discriminant analysis

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Effects of a 500-Mile Backpacking Hike on the Performance of a Competitive Powerlifter

The purpose of this study was to evaluate the effects of a long-distance backpacking trip and a high protein diet on body composition, strength, power, and aerobic performance. A single participant (male, aged 29 years) hiked 34 days on the Colorado Trail. Dependent variables were assessed pre-hike and post-hike and included body mass, body fat percentage, bone mineral density, maximum oxygen consumption (VO2max), resting metabolic rate (RMR), total cholesterol, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL). Cardiovascular dependent variables included resting heart rate, systolic blood pressure (SBP) and diastolic blood pressure (DBP). Other performance outcomes included strength in squat, bench press, and deadlift, and vertical leap. Resting heart rate and a journal documenting a breakdown of calories expended and calories consumed were recorded daily while on the hike. The average daily duration of a hike was 8:43 ± 1:45 hours. The participant’s mass decreased by 2.5 kg (4% of body weight), body fat decreased by 1.2%, RMR decreased by 5 kcal/day, and VO2max increased by 8.7 mL/kg/min (17%). Among metabolic variables, total cholesterol increased by 18 mg/dL (10%); triglyceride concentration decreased by 23 mg/dL (29%); HDL decreased by 1 mg/dL (2%), and; LDL increased by 24 mg/dL (23%). With regard to cardiovascular variables, resting heart rate decreased from 85 bpm to 67 bpm (21%), SBP decreased by 39 mmHg (27%), and DBP decreased by 2 mmHg (3%). Among performance variables, maximal squat performance decreased by 29.5 kg (19%), maximal bench press performance decreased by 18.2 kg (16%), maximal deadlift decreased 31.7 kg (17%), and vertical jump distance decreased 13 cm (14%). The average daily dietary variables were as follows: average calories consumed = 4000 ± 463 kcal/day; average calories expended from hiking and metabolic rate combined = 5188 ±1197 kcal/day; average daily caloric deficit = -1165 ± 1070 kcal/day; average carbohydrate intake = 501 ± 78 g/day; average protein intake = 143 ± 19 g/day; average fat intake = 154 ± 25g/day. The magnitude and duration of an extended backpacking trip can lead to a reduction in strength and power. A diet high in protein did not prevent the loss of lean body mass

X-Ray fluorescence analysis of feldspars and silicate glass: effects of melting time on fused bead consistency and volatilisation

Reproducible preparation of lithium tetraborate fused beads for XRF analysis of glass and mineral samples is of paramount importance for analytical repeatability. However, as with all glass melting processes, losses due to volatilization must be taken into account and their effects are not negligible. Here the effects of fused bead melting time have been studied for four Certified Reference Materials (CRM’s-three feldspars, one silicate glass), in terms of their effects on analytical variability and volatilization losses arising from fused bead preparation. At melting temperatures of 1065 °C, and for feldspar samples, fused bead melting times shorter than approximately 25 minutes generally gave rise to greater deviation of XRF-analyzed composition from certified composition. This variation might be due to incomplete fusion and / or fused bead inhomogeneity but further research is needed. In contrast, the shortest fused bead melting time for the silicate glass CRM gave an XRF-analyzed composition closer to the certified values than longer melting times. This may suggest a faster rate of glass-in-glass dissolution and homogenization during fused bead preparation. For all samples, longer melting times gave rise to greater volatilization losses (including sulphates and halides) during fusion. This was demonstrated by a linear relationship between SO3 mass loss and time1/2, as predicted by a simple diffusion-based model. Iodine volatilization displays a more complex relationship, suggestive of diffusion plus additional mechanisms. This conclusion may have implications for vitrification of iodine-bearing radioactive wastes. Our research demonstrates that the nature of the sample material impacts on the most appropriate fusion times. For feldspars no less than ~25 min and no more than ~60 min of fusion at 1065 °C, using Li2B4O7 as the fusion medium and in the context of feldspar samples and the automatic fusion equipment used here, strikes an acceptable (albeit non-ideal) balance between the competing factors of fused bead quality, analytical consistency and mitigating volatilization losses. Conversely, for the silicate glass sample, shorter fusion times of less than ~30 minutes under the same conditions provided more accurate analyses whilst limiting volatile losses

X-ray Fluorescence Analysis of Feldspars and Silicate Glass: Effects of Melting Time on Fused Bead Consistency and Volatilisation

Reproducible preparation of lithium tetraborate fused beads for XRF analysis of glass and mineral samples is of paramount importance for analytical repeatability. However, as with all glass melting processes, losses due to volatilisation must be taken into account and their effects are not negligible. Here the effects of fused bead melting time have been studied for four Certified Reference Materials (CRM’s: three feldspars, one silicate glass), in terms of their effects on analytical variability and volatilisation losses arising from fused bead preparation. At melting temperatures of 1065 °C, and for feldspar samples, fused bead melting times shorter than approximately 25 min generally gave rise to a greater deviation of the XRF-analysed composition from the certified composition. This variation might be due to incomplete fusion and/or fused bead inhomogeneity but further research is needed. In contrast, the shortest fused bead melting time for the silicate glass CRM gave an XRF-analysed composition closer to the certified values than longer melting times. This may suggest a faster rate of glass-in-glass dissolution and homogenization during fused bead preparation. For all samples, longer melting times gave rise to greater volatilisation losses (including sulphates and halides) during fusion. This was demonstrated by a linear relationship between SO3 mass loss and time1/2, as predicted by a simple diffusion-based model. Iodine volatilisation displays a more complex relationship, suggestive of diffusion plus additional mechanisms. This conclusion may have implications for vitrification of iodine-bearing radioactive wastes. Our research demonstrates that the nature of the sample material impacts on the most appropriate fusion times. For feldspars no less than ~25 min and no more than ~60 min of fusion at 1065 °C, using Li2B4O7 as the fusion medium and in the context of feldspar samples and the automatic fusion equipment used here, strikes an acceptable (albeit non-ideal) balance between the competing factors of fused bead quality, analytical consistency and mitigating volatilisation losses. Conversely, for the silicate glass sample, shorter fusion times of less than ~30 min under the same conditions provided more accurate analyses whilst limiting volatile losses

The Effects of Cannabidiol Supplementation on Measures of Performance and Fatigue Following Eccentric Exercise

Following intense exercise, there is a period of time where performance is decreased. This period of reduced performance is characterized by several factors including myofibrillar disruption, reduced range-of-motion, inflammation, and an influx of enzymes and proteins. Cannabidiol (CBD) has been marketed as a recovery supplement capable of reducing markers of fatigue and inflammation following exercise, yet this claim has not been investigated. PURPOSE: The purpose of this study was to determine if CBD supplementation limits fatigue and expedites a return to performance following intense eccentric exercise. METHODS: A double-blind, crossover design with repeated measures was used. Twenty-four NCAA female athletes (age = 21.2 ± 1.8 yrs., height = 166.4 ± 8 cm, weight = 64.9 ± 9.1 kg) were randomized to either receive 5 mg/kg of CBD in pill form (Cannabidiol Life, Longwood, FL) or a matched weight placebo. Treatments were consumed two hours prior to, immediately following, and ten hours following muscle damage sessions. All participants consumed both treatments, with each separated by approximately 28 days to control for the menstrual cycle. To induce muscle damage, participants completed 10 sets of 10 repetitions of unilateral eccentric leg extension at 60°/sec on an isokinetic dynamometer (Biodex Medical Systems Inc., Shirley, NY). Concentrations of a blood marker indicative of muscle damage (myoglobin), in addition to measures of fatigue (visual analogue fatigue scale [VAFS]) and performance (vertical jump, peak dynamic knee extensor torque at 60, 180, and 300°/sec, and peak isometric knee extensor torque), were collected before and 4, 24, and 48 hours following muscle damaging sessions. A repeated measures MANOVA was conducted to analyze the performance measures, and separate repeated measures ANOVAs were conducted to analyze myoglobin concentrations and results from the VAFS with a significance level of 0.05. RESULTS: A significant increase (p = 0.002) in myoglobin levels was observed for both treatments 4 hours following the muscle damaging session but no significant differences (p \u3e 0.05) were observed between the CBD and placebo groups at any of the 4 measured time points. Peak torque at 60°/sec (p = 0.001) and peak isometric torque (p = 0.02) were significantly lower 24 hours following muscle damage, but none of the 5 measured performance variables were significantly different (p \u3e 0.05 for all) between the CBD and placebo treatment at any time point. Subjective fatigue as measured by the VAFS was not significantly different (p \u3e 0.05) between the CBD and placebo treatments at any measured time point. CONCLUSION: Cannabidiol supplementation was unable to reduce fatigue and restore performance when compared to a placebo in well-trained female participants. It does not appear that CBD supplementation is of beneficial use as a recovery supplement following intense exercise in athletes

Spectroscopic Confirmation of a z=2.79 Multiply Imaged Luminous Infrared Galaxy Behind the Bullet Cluster

We report spectroscopic confirmation and high-resolution infrared imaging of a z=2.79 triply-imaged galaxy behind the Bullet Cluster. This source, a Spitzer-selected luminous infrared galaxy (LIRG), is confirmed via polycyclic aromatic hydrocarbon (PAH) features using the Spitzer Infrared Spectrograph (IRS) and resolved with HST WFC3 imaging. In this galaxy, which with a stellar mass of M*=4e9 Msun is one of the two least massive ones studied with IRS at z>2, we also detect H_2 S(4) and H_2 S(5) pure rotational lines (at 3.1 sigma and 2.1 sigma) - the first detection of these molecular hydrogen lines in a high-redshift galaxy. From the molecular hydrogen lines we infer an excitation temperature T=377+68-84 K. The detection of these lines indicates that the warm molecular gas mass is 6(+36-4)% of the stellar mass and implies the likely existence of a substantial reservoir of cold molecular gas in the galaxy. Future spectral observations at longer wavelengths with facilities like the Herschel Space Observatory, the Large Millimeter Telescope, and the Atacama Pathfinder EXperiment (APEX) thus hold the promise of precisely determining the total molecular gas mass. Given the redshift, and using refined astrometric positions from the high resolution imaging, we also update the magnification estimate and derived fundamental physical properties of this system. The previously published values for total infrared luminosity, star formation rate, and dust temperature are confirmed modulo the revised magnification; however we find that PAH emission is roughly a factor of five stronger than would be predicted by the relations between the total infrared and PAH luminosity reported for SMGs and starbursts in Pope et al. (2008).Comment: 8 pages, 4 figures, accepted to Ap

A Wearable Sensor to Mitigate Shoulder Injury in Astronauts

The prevalence of shoulder pain has been documented to be as high as 56% among astronauts who perform extravehicular activities (EVA) while training. The prevalence of shoulder injuries in astronauts required NASA to assemble a research team, called the Shoulder Tiger Team, nearly 20 years ago. In 2003, this team concluded that the majority of the shoulder injuries occur while the astronaut is wearing the hard upper torso unit (HUT) of their space suit during EVA training missions in the neutral buoyancy lab (NBL). These injuries typically carry-over to the actual mission, and required EVAs, which can negatively affect job performance duties performed by astronauts. We chose to create a warning system that is able to collect angular displacement data at the shoulder and, at a potentially dangerous range of motion, send tactile (vibrational) feedback to the astronaut. PURPOSE: To design a cost effective, wearable, tactile feedback sensor to help mitigate shoulder injury during EVA training. METHODS: A custom fitted, upper-body garment that contained a tactile feedback sensor capable of delivering a vibrational signal was originally designed in three-dimensional modeling software (Solidworks Premium 2018, Waltham, MA). The sensor and all associated components were integrated into a compression sleeve, which is personalized to each astronauts’ anthropometrics. The components are removable and interchangeable for ease of maintenance. These components include a microcontroller, flex sensors, haptic motor driver, vibration mini motor discs, and battery. The sensor components were strategically placed at anatomical locations to maximize comfort and function: 1) anterior flex sensor: placed on the deltoid, extending from medial to lateral; 2) posterior flex sensor: extended from the lateral end of supraspinatus to the middle deltoid; 3) microcontroller: placed on the inferior angle of the scapular spine; 4) vibration motor discs: placed on the sternum and upper tricep, and; 5) haptic motor driver: placed directly superior to the vibration motor. RESULTS: In order to correlate range of motion with the resistance of the flex sensors, a goniometer was used to measure the range of motion of shoulder abduction and shoulder flexion while recording resistance data in the serial monitor. The mapped resistance value recorded at 90 degrees for shoulder joint flexion was approximately 57 kohms. The mapped resistance value recorded at 90 degrees for shoulder abduction was approximately 37 kohms. We also developed a protocol to improve the muscular endurance of the small upper back muscles and shoulder stabilizers. It is a 3-day strengthening program that will be complemented with the regular EVA mission training for each astronaut. CONCLUSION: Shoulder injuries are one of the most common issues affecting astronauts who undergo EVA training. A vibrational feedback sensor may mitigate the potentially harmful shoulder positions during this training

Uptake of Screening for Breast Cancer in South Lancashire

Study objective: To describe and explain variation among general practices in the uptake of screening for breast cancer. Design: Analysis of the variation in uptake of screening by general practice. Uptake rates are calculated and related to a social deprivation score created for each practice, and to the presence of at least one female general practitioner. Setting: South Lancashire Health Authority, England. Patients: All women aged 50–64 y registered with Lancashire Family Health Services Authority and resident in South Lancashire in 1988–1995. Main results: Variation in the uptake of screening for breast cancer during Round 1 of the national programme is explained partly by a deprivation score for each practice and by the presence of at least one female general practitioner. In Round 2 the deprivation index continues to explain variation, but the effect of a female GP has diminished. The number of hours worked by practice nurses has no effect on uptake of breast screening. Conclusions: Variation in the uptake of breast cancer screening is closely related to social deprivation. Results suggest that the presence of a female general practitioner has a beneficial effect on uptake