Learning as We Go: An Examination of the Statistical Accuracy of COVID19 Daily Death Count Predictions

This paper provides a formal evaluation of the predictive performance of a model (and its various updates) developed by the Institute for Health Metrics and Evaluation (IHME) for predicting daily deaths attributed to COVID19 for each state in the United States. The IHME models have received extensive attention in social and mass media, and have influenced policy makers at the highest levels of the United States government. For effective policy making the accurate assessment of uncertainty, as well as accurate point predictions, are necessary because the risks inherent in a decision must be taken into account, especially in the present setting of a novel disease affecting millions of lives. To assess the accuracy of the IHME models, we examine both forecast accuracy as well as the predictive performance of the 95% prediction intervals provided by the IHME models. We find that the initial IHME model underestimates the uncertainty surrounding the number of daily deaths substantially. Specifically, the true number of next day deaths fell outside the IHME prediction intervals as much as 70% of the time, in comparison to the expected value of 5%. In addition, we note that the performance of the initial model does not improve with shorter forecast horizons. Regarding the updated models, our analyses indicate that the later models do not show any improvement in the accuracy of the point estimate predictions. In fact, there is some evidence that this accuracy has actually decreased over the initial models. Moreover, when considering the updated models, while we observe a larger percentage of states having actual values lying inside the 95% prediction intervals (PI), our analysis suggests that this observation may be attributed to the widening of the PIs. The width of these intervals calls into question the usefulness of the predictions to drive policy making and resource allocation

Cutaneous Arteriolar Dilation Elicited By Ultraviolet Irradiation

Arteriolar changes in the skin following monochromatic UV irradiation have been investigated with a photoelectric pulsemeter. Arteriolar dilatation was seen at all wavelengths tested and could be detected as early as 2 hours after irradiation. Intradermal epinephrine was found to produce marked pallor of UV erythema and arteriolar constriction was confirmed with the pulsemeter.Recordings indicating arteriolar dilatation were identical with 250 nm and 300 nm erythema, despite well documented qualitative differences in the erythema at these wavelengths

Maturity, physical ability, technical skill and coaches\u27 perception of semi-elite adolescent Australian footballers

Purpose: To confirm the effect of maturational differences on anthropometric and physical testing and explore the effect of maturation on technical skill and coaches’ perceptions of skill in adolescent Australian footballers. Methods: Athletes were recruited from a semi-elite under 16 competition (n = 94, age 15.7 ± 0.3 years) and completed anthropometric, physical, and technical skill tests. Coaches from each team provided subjective ratings of athletes’ technical skills. Maturation groups were derived from years from peak height velocity estimates, with classifications either later, average or earlier maturing. Results: Effect size comparisons revealed very large to moderate effects between groups for anthropometric measures and performance in sprint and jump tasks. Small to moderate effects were reported between groups for coaches’ perceptions of skill, with the earlier maturing group perceived to have better overall technical skills, marking and ball winning abilities. Small to trivial effects were reported for performance in the technical skill tests. Conclusions: Despite no differences in skill tests, earlier maturing athletes may be afforded significant selection and competition advantages due to advanced physical capacities and coaches’ perceptions of skill

Coaches\u27 perceptions of long-term potential are biased by maturational variation

Talent identification and development programs seek to recognise and promote athletes with long-term potential in a particular sport. Coaches involved in these programs are often required to make inclusions or exclusion decisions based on their perceptions of an athlete’s long-term potential. However, biological maturity can influence physical capabilities of adolescent athletes and may bias coaches’ perceptions of long-term potential. This study explored the relationship between coaches’ perceptions of long-term potential and variations in athlete’s biological maturity. Talented adolescent male Australian footballers from nine (n = 264) different teams were recruited to provide basic anthropometric information for estimates of biological maturity. Coaches from each team were recruited to provide a rating of their own player’s long-term potential. Coaches perceived late maturing athletes to have a significantly lower long-term potential than their average (χ2 = 9.42, p \u3c 0.01) and early (χ2 =  5.86, p = 0.04) maturing counterparts. Of the late maturing athletes, 72% were predicted to go no further than adolescent competition. No concurrent bias was evident between the average or early maturing athletes. The findings of this study demonstrate coaches perceptions of long-term potential can be biased by maturational variation in adolescent athletes. Such perceptual bias may impact on coaches selection decisions and result in talented but late maturing athletes missing selection into development pathways

The effect of farming system on dairy cow cleanliness in the UK and implications to udder health

The cleanliness of dairy cows was assessed using a 20 point hygiene score system at different times in the year on 14 organic and 14 conventional farms in the UK. Overall, cows were dirtier during winter housing compared to summer grazing. Farming system had no effect on cow cleanliness when cows were at grass, but when housed in the winter, organic cows were more likely to be cleaner. There was a link between cow hygiene scores and milk hygiene, with herds having lower bulk tank somatic cell counts (BTSCC) tending to have cleaner cows. This relationship was strongest for the organic herds. There was no significant link between hygiene score and Bactoscan (BS) count or mastitis incidence

Pharmaceutical transition to non-CFC pressurized metered dose inhalers

The production of ozone-depleting chlorofluorocarbons (CFCs) was discontinued on 1 January 1996 for all uses deemed non-essential under the Montreal Protocol. However, the use of CFCs as propellants in pressurized metered dose inhalers (pMDIs) was classed as essential, providing an exemption from the agreement. Following extensive research, the hydrofluoroalkanes (HFA) 134a and 227 were identified as the only suitable replacements for CFC propellants in pMDIs.The drug delivery of pMDIs formulated with HFA 134a as a propellant and containing either salbutamol (100 μg per actuation) or fluticasone propionate (125 and 250 μg per actuation) have been assessed for dose uniformity and particle size distribution.All of the HFA 134a pMDIs delivered doses throughout the life of the canisters that were reproducible and within specified regulatory requirements. Each of the products provided an emitted dose which was within ±25% of the mean value indicating accurate and consistent dosing (93, 112 and 221 μg per metered dose for the salbutamol 100 μg and fluticasone propionate 125 and 250 μg HFA 134a pMDIs, respectively). These findings were unaffected by changing the storage orientation of the pMDI or by using the device in a manner designed to simulate typical patient use. The particle size distributions of HFA 134a pMDI doses did not differ significantly from those of the corresponding CFC pMDIs. As a result of the similar pharmaceutical performance, it is unnecessary to change the label claim dose of active drug when making the transition from a CFC to an HFA 134a pMDI for salbutamol (VentolinTM) and fluticasone propionate (FlixtideTM). A seamless transition to non-CFC pMDIs will help to maintain the confidence of patients and healthcare professionals in asthma therapy

ADDING MASS TO THE SHOE DOES NOT AFFECT BALL VELOCITY IN A SOCCER PENALTY KICK

The aim of this study was to identify the optimum shoe mass that maximizes ball velocity in a soccer instep penalty kick. Two players performed 20–30 maximum-effort penalty kicks while wearing football shoes with lead weights attached to the base of the shoe (total mass: 0.26 – 0.81 kg). The kicks were recorded by a video camera at 100 Hz and a biomechanical analysis was conducted to obtain measures of ball projection velocity and kinematics of the kicking leg. We found that ball velocity was insensitive to shoe mass (at least for the range of shoe mass tested). An important contributing factor to the observed relationship was that the velocity of the kicking foot at ball impact decreased as the mass of the shoe increased. Our result indicates that players should not change their shoes before taking a penalty kick

Lactobacillus fermentum (PCC®) supplementation and gastrointestinal and respiratory-tract illness symptoms: a randomised control trial in athletes

BACKGROUND Probiotics purportedly reduce symptoms of gastrointestinal and upper respiratory-tract illness by modulating commensal microflora. Preventing and reducing symptoms of respiratory and gastrointestinal illness are the primary reason that dietary supplementation with probiotics are becoming increasingly popular with healthy active individuals. There is a paucity of data regarding the effectiveness of probiotics in this cohort. The aim of this study was to evaluate the effectiveness of a probiotic on faecal microbiology, self-reported illness symptoms and immunity in healthy well trained individuals. METHODS Competitive cyclists (64 males and 35 females; age 35 ± 9 and 36 ± 9 y, VO2max 56 ± 6 and 52 ± 6 ml.kg-1.min-1, mean ± SD) were randomised to either probiotic (minimum 1 × 109 Lactobacillus fermentum (PCC®) per day) or placebo treatment for 11 weeks in a double-blind, randomised, controlled trial. The outcome measures were faecal L. fermentum counts, self-reported symptoms of illness and serum cytokines. RESULTS Lactobacillus numbers increased 7.7-fold (90% confidence limits 2.1- to 28-fold) more in males on the probiotic, while there was an unclear 2.2-fold (0.2- to 18-fold) increase in females taking the probiotic. The number and duration of mild gastrointestinal symptoms were ~2-fold greater in the probiotic group. However, there was a substantial 0.7 (0.2 to 1.2) of a scale step reduction in the severity of gastrointestinal illness at the mean training load in males, which became more pronounced as training load increased. The load (duration×severity) of lower respiratory illness symptoms was less by a factor of 0.31 (99%CI; 0.07 to 0.96) in males taking the probiotic compared with placebo but increased by a factor of 2.2 (0.41 to 27) in females. Differences in use of cold and flu medication mirrored these symptoms. The observed effects on URTI had too much uncertainty for a decisive outcome. There were clear reductions in the magnitude of acute exercise-induced changes in some cytokines. CONCLUSION L. fermentum may be a useful nutritional adjunct for healthy exercising males. However, uncertainty in the effects of supplementation on URTI and on symptoms in females needs to be resolved. TRIAL REGISTRATION The trial was registered in the Australia and New Zealand Clinical Trials Registry (ACTRN12611000006943).The study was funded by Christian Hansen A/S, Probiomics and the Australian Institute of Sport

A Case Study on Accessible Reading with Deaf Children

The concept of accessible reading for deaf students is new and worthy of exploration. In the face of the reading difficulties often experienced by deaf students, the lack of a specialized reading methodology that works for them must be addressed. Central to the paper is a research case study undertaken with two young deaf students, proficient in American Sign Language (ASL) and learning to read. The students participated in a tutorial with a tutor knowledgeable in a specialized reading methodology called ASL Gloss. The participating students demonstrated progress in reading skills over time. Two reading measures were adapted from English to ASL for use with deaf students. Some important features of ASL Gloss are included in the study report. The manipulated English text that closer resembles ASL and the use of the ASL-phabet, are designed to facilitate deaf students’ needed transition from ASL to English literacy (Supalla, 2017; Supalla & Cripps, 2011; Supalla et al., 2001). These deaf students engage in oral reading (in ASL) and are also given a different task. That is, to identify ASL-phabet letters that represent the phonological structure of signed words. The reading measures under development appear to promote the process of learning to read as informed by the quantitative and qualitative data. These findings support the need and promise of pursuing an alternative theory and applied research for deaf students’ reading that accounts for their ability to become fluent readers

Schjeldahl Dale connectors

The Schjeldahl Dale connector was found to be best suited to the ALSEP environment and Array E program constraints (Memo 9713-325). More rigorous control of manufacture and assembly operations will ensure a highly reliable connector. This ATM details the steps to be taken to achieve this high reliability.prepared by G. A. Cripps