Computer Programs for Calculating and Plotting the Stability Characteristics of a Balloon Tethered in a Wind

Computer programs for calculating the stability characteristics of a balloon tethered in a steady wind are presented. Equilibrium conditions, characteristic roots, and modal ratios are calculated for a range of discrete values of velocity for a fixed tether-line length. Separate programs are used: (1) to calculate longitudinal stability characteristics, (2) to calculate lateral stability characteristics, (3) to plot the characteristic roots versus velocity, (4) to plot the characteristic roots in root-locus form, (5) to plot the longitudinal modes of motion, and (6) to plot the lateral modes for motion. The basic equations, program listings, and the input and output data for sample cases are presented, with a brief discussion of the overall operation and limitations. The programs are based on a linearized, stability-derivative type of analysis, including balloon aerodynamics, apparent mass, buoyancy effects, and static forces which result from the tether line

Influenza Vaccination Coverage among Adults with Asthma: Findings from the 2000 Behavioral Risk Factor Surveillance System

The prevalence of asthma has increased substantially in the United States since 1980 (1). The primary clinical and public health strategy to reduce the burden of asthma is to prevent exacerbation of the disease, of which upper and lower respiratory tract infections are a major cause (2–5). One such infection—influenza— and its complications are potentially preventable with annual vaccination, which is a safe and effective method (6,7), including among persons with asthma (8). Because persons with asthma are at increased risk of complications from influenza, they are advised to receive annual influenza vaccinations (9), unless there are contraindications. Little is known about how adults with asthma or health care providers comply with the annual influenza vaccination recommendations issued by the Advisory Committee on Immunization Practices (9). Among children with asthma, however, vaccination levels are low (10 –15). We therefore sought to assess the influenza vaccination coverage among adults with asthma, as well as to identify predictors of receiving such a vaccination

Effects of 28 days of resistance exercise and consuming a commercially available pre-workout supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers in males

This study determined the effects of 28 days of heavy resistance exercise combined with the nutritional supplement, NO-Shotgun(R) on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers

Ingestion of 10 grams of whey protein prior to a single bout of resistance exercise does not augment Akt/mTOR pathway signaling compared to carbohydrate

Background: This study examined the effects of a whey protein supplement in conjunction with an acute bout of lower body resistance exercise, in recreationally-active males, on serum insulin and insulin like growth factor 1 (IGF-1) and Akt/mTOR signaling markers indicative of muscle protein synthesis: insulin receptor substrate 1 (IRS-1), AKT, mammalian target of rapamycin (mTOR), p70S6 kinase (p70S6K) and 4E-binding protein 1 (4E-BP1).Methods: In a randomized, double-blind, cross-over design, 10 males ingested 1 week apart, either 10 g of whey protein (5.25 g EAAs) or carbohydrate (maltodextrose), 30 min prior to a lower-body resistance exercise bout. The resistance exercise bout consisted of 4 sets of 8-10 reps at 80% of the one repetition maximum (RM) on the angled leg press and knee extension exercises. Blood and muscle samples were obtained prior to, and 30 min following supplement ingestion and 15 min and 120 min post-exercise. Serum and muscle data were analyzed using two-way ANOVA.Results: No significant differences were observed for IGF-1 (p > 0.05). A significant main effect for Test was observed for serum insulin (p 0.05). For the Akt/MTOR signaling intermediates, no significant Supplement × Test interactions were observed (p > 0.05). However, significant main effects for Test were observed for phosphorylated concentrations of IRS, mTOR, and p70S6K, as all were elevated at 15 min post-exercise (p < 0.05). Additionally, a significant main effect for Test was noted for 4E-BP1 (p < 0.05), as it was decreased at 15 min post-exercise.Conclusion: Ingestion of 10 g of whey protein prior to an acute bout of lower body resistance exercise had no significant preferential effect compared to carbohydrate on systemic and cellular signaling markers indicative of muscle protein synthesis in untrained individuals

Hierarchical Patterns of Global Human Y-Chromosome Diversity

We examined 43 biallelic polymorphisms on the nonrecombining portion of the Y chromosome (NRY) in 50 human populations encompassing a total of 2,858 males to study the geographic structure of Y-chromosome variation. Patterns of NRY diversity varied according to geographic region and method/level of comparison. For example, populations from Central Asia had the highest levels of heterozygosity, while African populations exhibited a higher level of mean pairwise differences among haplotypes. At the global level, 36% of the total variance of NRY haplotypes was attributable to differences among populations (i.e., Phi(ST) = 0.36). When a series of AMOVA analyses was performed on different groupings of the 50 populations, high levels of among-groups variance (Phi(CT)) were found between Africans, Native Americans, and a single group containing all 36 remaining populations. The same three population groupings formed distinct clusters in multidimensional scaling plots. A nested cladistic analysis (NCA) demonstrated that both population structure processes (recurrent gene flow restricted by isolation by distance and long-distance dispersals) and population history events (contiguous range expansions and long-distance colonizations) were instrumental in explaining this tripartite division of global NRY diversity. As in our previous analyses of smaller NRY data sets, the NCA detected a global contiguous range expansion out of Africa at the level of the total cladogram. Our new results support a general scenario in which, after an early out-of-Africa range expansion, global-scale patterns of NRY variation were mainly influenced by migrations out of Asia. Two other notable findings of the NCA were (1) Europe as a "receiver" of intercontinental signals primarily from Asia, and (2) the large number of intracontinental signals within Africa. Our AMOVA analyses also supported the hypothesis that patrilocality effects are evident at local and regional scales, rather than at intercontinental and global levels. Finally, our results underscore the importance of subdivision of the human paternal gene pool and imply that caution should be exercised when using models and experimental strategies based on the assumption of panmixia

Determining the prevalence of tuberculosis in emergency departments in the Eastern Cape region of South Africa and the utility of the World Health Organization tuberculosis screening tool

Background. South Africa (SA) faces a significant tuberculosis (TB) burden complicated by high rates of HIV-TB co-infection. In SA, emergency departments (EDs) play an important role in screening for TB.Objectives. To determine the prevalence of TB in the ED and the effectiveness of the World Health Organization (WHO) TB screening tool.Methods. This was a cross-sectional observational study, conducted in the ED at Livingstone Hospital, Port Elizabeth, from 4 June to 15 July 2018. All patients aged &gt;18 years and able to consent were administered the WHO TB screening questions and underwent a point-of-care HIV test and demographic data collection. Patients were followed up for 1 year and tracked in the National Health Laboratory Service database to determine TB status using laboratory testing.Results. Over the study period, 790 patients were enrolled. Overall, 121 patients (15.3%) were TB-positive, with 46 (38.0%) diagnosed after presenting to the ED and 75 (62.0%) with a previous TB history determined by self-report or confirmed laboratory testing. A greater proportion of the TB-positive patients were HIV-positive (49.6%) compared with the TB-negative population (24.8%). TB-positive individuals were more likely to present to the ED with a chief complaint of shortness of breath (SoB) (18.2%) compared with the TB-negative population (10.5%). Overall, the WHO TB screening tool had poor sensitivity (46.5%) and specificity (62.5%) for identifying TB-positive patients in the ED. A multiple logistic regression analysis, controlled for age and sex, showed HIV status (odds ratio (OR) 2.81; p&lt;0.001) and SoB (OR 2.19; p&lt;0.05) to be significant predictors of TB positivity. Adding positive HIV status and a presenting complaint of SoB increased sensitivity to 78.3%.Conclusions. EDs in SA face a high burden of TB. While WHO screening guidelines identify some of these patients, including routine HIV testing in the ED could significantly affect the number of TB diagnoses made

Limited HIV-1 superinfection in seroconverters from the CAPRISA 004 Microbicide trial.

CAPRISA, 2014.HIV-1 superinfection (SI) occurs when an infected individual acquires a distinct new viral strain. The rate of superinfection may be reflective of the underlying HIV risk in a population. The Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 clinical trial demonstrated that women who used a tenofovir-containing microbicide gel had lower rates of HIV infection than women using a placebo gel. Women who contracted HIV-1 during the trial were screened for the occurrence of superinfection by next-generation sequencing of the viral gag and env genes. There were two cases (one in each trial arm) of subtype C superinfection identified from the 76 women with primary infection screened at two time points (rate of superinfection, 1.5/100 person-years). Both women experienced a >0.5-log increase in viral load during the window when superinfection occurred. The rate of superinfection was significantly lower than the overall primary HIV incidence in the microbicide trial (incidence rate ratio [IRR], 0.20; P=0.003). The women who seroconverted during the trial reported a significant increase in sexual contact with their stable partner 4 months after seroconversion (P<0.001), which may have lowered the risk of superinfection in this population. The lower frequency of SI compared to the primary incidence is in contrast to a report from a general heterosexual African population but agrees with a study of high-risk women in Kenya. A better understanding of the rate of HIV superinfection could have important implications for ongoing HIV vaccine research

Determining the prevalence of tuberculosis in emergency departments in the Eastern Cape region of South Africa and the utility of the World Health Organization tuberculosis screening tool

Background. South Africa (SA) faces a significant tuberculosis (TB) burden complicated by high rates of HIV-TB co-infection. In SA, emergency departments (EDs) play an important role in screening for TB. Objectives. To determine the prevalence of TB in the ED and the effectiveness of the World Health Organization (WHO) TB screening tool. Methods. This was a cross-sectional observational study, conducted in the ED at Livingstone Hospital, Port Elizabeth, from 4 June to 15 July 2018. All patients aged &gt;18 years and able to consent were administered the WHO TB screening questions and underwent a point-of-care HIV test and demographic data collection. Patients were followed up for 1 year and tracked in the National Health Laboratory Service database to determine TB status using laboratory testing. Results. Over the study period, 790 patients were enrolled. Overall, 121 patients (15.3%) were TB-positive, with 46 (38.0%) diagnosed after presenting to the ED and 75 (62.0%) with a previous TB history determined by self-report or confirmed laboratory testing. A greater proportion of the TB-positive patients were HIV-positive (49.6%) compared with the TB-negative population (24.8%). TB-positive individuals were more likely to present to the ED with a chief complaint of shortness of breath (SoB) (18.2%) compared with the TB-negative population (10.5%). Overall, the WHO TB screening tool had poor sensitivity (46.5%) and specificity (62.5%) for identifying TB-positive patients in the ED. A multiple logistic regression analysis, controlled for age and sex, showed HIV status (odds ratio (OR) 2.81; p&lt;0.001) and SoB (OR 2.19; p&lt;0.05) to be significant predictors of TB positivity. Adding positive HIV status and a presenting complaint of SoB increased sensitivity to 78.3%. Conclusions. EDs in SA face a high burden of TB. While WHO screening guidelines identify some of these patients, including routine HIV testing in the ED could significantly affect the number of TB diagnoses made