Integral group actions on symmetric spaces and discrete duality symmetries of supergravity theories

For $G(\mathbb{R})$ a split, simply connected, semisimple Lie group of rank $n$ and $K$ the maximal compact subgroup of $G$, we give a method for computing Iwasawa coordinates of $G/K$ using the Chevalley generators and the Steinberg presentation. When $G/K$ is a scalar coset for a supergravity theory in dimensions $\geq 3$, we determine the action of the integral form $G(\mathbb{Z})$ on $G/K$. We give explicit results for the action of the discrete $U$--duality groups $SL_2(\mathbb{Z})$ and $E_7(\mathbb{Z})$ on the scalar cosets $SL_2(\mathbb{R})/SO_2(\mathbb{R})$ and $E_{7(+7)}(\mathbb{R})/[SU(8,\mathbb{R})/\{\pm Id\}]$ for type IIB supergravity in ten dimensions and 11--dimensional supergravity in $D=4$ dimensions, respectively. For the former, we use this to determine the discrete U--duality transformations on the scalar sector in the Borel gauge and we describe the discrete symmetries of the dyonic charge lattice. We determine the spectrum--generating symmetry group for fundamental BPS solitons of type IIB supergravity in $D=10$ dimensions at the classical level and we propose an analog of this symmetry at the quantum level. We indicate how our methods can be used to study the orbits of discrete U--duality groups in general

Physical Education and Blood Lipid Concentrations in Children: The LOOK Randomized Cluster Trial

BACKGROUND AND OBJECTIVES Elevated blood lipids during childhood are predictive of dyslipidemia in adults. Although obese and inactive children have elevated values, any potentially protective role of elementary school physical education is unknown. Our objective was to determine the effect of a modern elementary school physical education (PE) program on the blood lipid concentrations in community-based children. METHODS In this cluster-randomized controlled trial, 708 healthy children (8.1±0.3 years, 367 boys) in 29 schools were allocated to either a 4-year intervention program of specialist-taught PE (13 schools) or to a control group of the currently practiced PE conducted by generalist classroom teachers. Fasting blood lipids were measured at ages 8, 10, and 12 years and intervention and control class activities were recorded. RESULTS Intervention classes included more fitness work and more moderate and vigorous physical activity than control classes (both p3.36mmol.L(-1),130 mg/dL) was lower in the intervention than control group (14% vs. 23%, p = 0.02). There was also an intervention effect on mean LDL-C across all boys (reduction of 9.6% for intervention v 2.8% control, p = 0.02), but not girls (p = 0.2). The intervention effect on total cholesterol mirrored LDL-C, but there were no detectable 4-year intervention effects on high-density lipoprotein cholesterol or triglycerides. CONCLUSIONS The PE program delivered by specialist teachers over four years in elementary school reduced the incidence of elevated LDL-C in boys and girls, and provides a means by which early preventative practices can be offered to all children. TRIAL REGISTRATION Australia New Zealand Clinical Trial Registry ANZRN12612000027819 https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=347799.Sources of funding were The Commonwealth Education Trust (New Zealand House, London, UK) (http://www.commonwealth.org.uk/) and the Canberra Hospital Salaried Staff Specialists Fund (http://healthresearch.anu.edu.au/documents/PPFVACATION/ppf-major-info-2012.pdf). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Do self-reported stress and depressive symptoms effect endothelial function in healthy youth? The LOOK longitudinal study

BACKGROUND AND AIMS: Endothelial dysfunction is thought to be an early indicator of risk for cardiovascular disease and has been associated with both stress and depression in adults and adolescents. Less is known of these relationships in younger populations, where the origins of CVD is thought to manifest. This study examined the effects of questionnaire derived psychosocial stress and depressive symptoms on endothelial function among children, following them through to adolescence. METHOD: Participants were 203 grade 2 children (111 girls; M age = 7.6 ± 0.3 years) from the LOOK longitudinal study, who were followed through to adolescence (16 years). Self-reported psychosocial stress and depression were assessed using the validated Children\u27s Stress Questionnaire and a modified and validated version of the Children\u27s Depression Inventory respectively; endothelial function was assessed using EndoPAT 2000 system at follow-up only; and adjustments were made for fitness, pubertal development and socioeconomic status. RESULTS: Although all relationships occurred in the hypothesised direction, no cross-sectional or prospective evidence of early symptoms of psychological stress or depression being associated with endothelial dysfunction was found among our asymptomatic cohort of adolescents (all p > .05). CONCLUSIONS: In contrast to previous findings in adolescents, our data provided little evidence of any relationship between current or previous psychosocial stress or depression and endothelial function in 16-year-old boys and girls. However, our data need to be interpreted alongside the potential limitations in the sensitivity associated with self-report methods for detecting psychological distress of children

Outcomes of a four-year specialist-taught physical education program on physical activity: a cluster randomized controlled trial, the LOOK study

BackgroundThe objective of this study was to investigate the effect of a 4-year specialist-taught Physical Education (PE) program on physical activity (PA) among primary school children.MethodsA 4-year cluster randomised controlled trial was conducted in children (initially aged 8 years) from 29 primary schools (13 Intervention, 16 Control). Intervention students (N&thinsp;=&thinsp;457) received 2&thinsp;&times;&thinsp;45 min PE lessons per week from specialist-trained PE teachers (68 lessons per year, 272 lessons over 4 years). Control group students (N&thinsp;=&thinsp;396) received usual practice PE from generalist classroom teachers. PA during PE lessons was examined using the System for Observing Fitness Instruction Time (SOFIT). Pedometers (steps/day) were worn for 7 days each year, and accelerometers were worn concurrently in the final two years to assess moderate to vigorous (MVPA) and sedentary activity. Linear and generalized mixed models were used to determine differences in Intervention and Control student PA and the proportion of students meeting PA guidelines.ResultsThe intervention increased SOFIT-observed student MVPA during PE lessons by 6.5 mins (16.7 v 10.2, p&thinsp;&lt;&thinsp;0.001). Within intervention schools, participants increased their whole-day step counts (boys&thinsp;=&thinsp;449 [CI,140 to 756]; girls&thinsp;=&thinsp;424 [CI,222 to 626]) and minutes of MVPA (boys&thinsp;=&thinsp;8.0 [CI,6.8 to 9.2]; girls&thinsp;=&thinsp;3.5 [CI,1.7 to 5.4]) on PE days. However, compared to the Control group the Intervention did not: increase habitual steps/day or MVPA when averaged over 7 days; elicit greater improvements in these measures over time; or increase the odds of meeting step/day or MVPA recommendations. At age 11 years Intervention group boys were 20 mins less sedentary per day (380 [CI,369 to 391] vs 360 [CI,350 to 369]) and this effect was sustained at age 12 years.ConclusionsWell-designed specialist-taught PE can improve student PA during PE lessons. However for PE to be a significant contributor to improving habitual PA in pre-adolescent children, daily classes are likely to be required, and even this would need to be supplemented with a wider multicomponent strategy. Our finding of a reduction in sedentary time among Intervention boys warrants further investigation into the potential role PE could play in influencing sedentary behaviour.<br /

Cross-Sectional Associations of Total Daily Volume and Activity Patterns across the Activity Spectrum with Cardiometabolic Risk Factors in Children and Adolescents

Sedentary and physical activity patterns (bouts/breaks) may be important for cardiometabolic health in early life. This study aimed to examine cross-sectional associations of total daily volume and patterns across the activity spectrum with cardiometabolic risk factors in youth aged 7–13 years. Objectively measured accelerometer and cardiometabolic risk factor data were pooled from two studies (n = 1219; 69% valid accelerometry). Total daily volume of sedentary time and light-, moderate-, and vigorous-intensity physical activity was determined. Time in sustained bouts and median bout lengths of all intensities and breaks in sedentary time were also calculated. Outcomes included body mass index, waist circumference, blood pressure, blood lipids, and a cardiometabolic summary score. Regression models revealed beneficial associations between total daily volumes of moderate- and vigorous-intensity physical activity and cardiometabolic risk. Time spent in ≥1 min vigorous-intensity physical activity bouts was beneficially associated with cardiometabolic risk, yet this disappeared after adjusting for total vigorous-intensity physical activity and confounders. Time accumulated in light- (≥1 min; ≥5 min) and moderate-intensity (≥1 min) physical activity bouts was detrimentally associated with cardiometabolic risk. Total daily volume and activity patterns may have implications for cardiometabolic risk early in life. Sporadic physical activity may be more beneficial for health than sustained physical activity

Child and Parent Physical Activity, Sleep, and Screen Time During COVID-19 and Associations With Mental Health:Implications for Future Psycho-Cardiological Disease?

The COVID-19 pandemic has afforded the opportunity for some to improve lifestyle behaviours, while for others it has presented key challenges. Adverse changes in global lifestyle behaviours, including physical activity, sleep, and screen time can affect proximal mental health and in turn distal cardiovascular outcomes. We investigated differences in physical activity, sleep, and screen time in parents and children during early stages of the COVID-19 pandemic in Australia compared to pre-COVID-19 national data; and estimated associations between these movement behaviours with parent and child mental health. Cross-sectional baseline data from the COVID-19 Pandemic Adjustment Study (CPAS; N = 2,365) were compared to nationally representative pre-pandemic data from the Longitudinal Study of Australian Children (LSAC; N = 9,438). Participants were parents of children aged ≤ 18 years, residing in Australia. Parents provided self-report measures of mental health, physical activity and sleep quality, and reported on child mental health, physical activity and screen time. Children in CPAS had significantly more sleep problems and more weekend screen time. Their parents had significantly poorer sleep quality, despite increased weekly physical activity. Children's sleep problems were significantly associated with increased mental health problems, after accounting for socioeconomic status, physical activity, and screen time. Poorer parent sleep quality and lower levels of physical activity were significantly associated with poorer mental health. Monitoring this cohort over time will be important to examine whether changes in movement behaviour are enduring or naturally improve with the easing of restrictions; and whether these changes have lasting effects on either parent or child mental health, and in turn, future risk for CVD

Activity Accumulation and Cardiometabolic Risk in Youth

Introduction This cross-sectional study aimed to: i) identify and characterize youth according to distinct physical activity (PA) and sedentary (SED) accumulation patterns; and ii) investigate associations of these derived patterns with cardiometabolic risk factors.Methods ActiGraph accelerometer data from 7-13 year olds from two studies were pooled (n=1,219; 843 [69%] with valid accelerometry included in analysis). Time accumulated in ≥5-min and ≥10-min SED bouts, ≥1-min and ≥5-min bouts of light (LPA), and ≥1-min bouts of moderate (MPA) and vigorous (VPA) PA were calculated. Frequency of breaks in SED were also obtained. Latent profile analysis was used to identify groups of participants based on their distinct accumulation patterns. Linear and logistic regression models were used to test associations of group accumulation patterns with cardiometabolic risk factors, including adiposity indicators, blood pressure and lipids. Total PA and SED time were also compared between groups.Results Three distinct groups were identified: “Prolonged sitters” had the most time in prolonged SED bouts and the least time in VPA bouts; “Breakers” had the highest frequency of SED breaks and lowest engagement in sustained bouts across most PA intensities; “Prolonged movers” had the least time accumulated in SED bouts and the most in PA bouts across most intensities. Whilst “Breakers” engaged in less time in PA bouts compared to other groups, they had the healthiest adiposity indicators. No associations with the remaining cardiometabolic risk factors were found.Conclusion Youth accumulate their daily activity in three distinct patterns (prolonged sitters, breakers and prolonger movers), with those breaking up sitting and most time in sporadic PA across the day having a lower adiposity risk. No relationships with other cardiometabolic risk factors were identified

Sexual Behaviors and HIV Status: A Population-Based Study Among Older Adults in Rural South Africa

Objective: To identify the unmet needs for HIV prevention among older adults in rural South Africa. Methods: We analyzed data from a population-based sample of 5059 men and women aged 40 years and older from the study Health and Aging in Africa: Longitudinal Studies of INDEPTH Communities (HAALSI), which was carried out in the Agincourt health and sociodemographic surveillance system in the Mpumalanga province of South Africa. We estimated the prevalence of HIV (laboratory-confirmed and self-reported) and key sexual behaviors by age and sex. We compared sexual behavior profiles across HIV status categories with and without age–sex standardization. Results: HIV prevalence was very high among HAALSI participants (23%, 95% confidence interval [CI]: 21 to 24), with no sex differences. Recent sexual activity was common (56%, 95% CI: 55 to 58) across all HIV status categories. Condom use was low among HIV-negative adults (15%, 95% CI: 14 to 17), higher among HIV-positive adults who were unaware of their HIV status (27%, 95% CI: 22 to 33), and dramatically higher among HIV-positive adults who were aware of their status (75%, 95% CI: 70 to 80). Casual sex and multiple partnerships were reported at moderate levels, with slightly higher estimates among HIV-positive compared to HIV-negative adults. Differences by HIV status remained after age–sex standardization. Conclusions: Older HIV-positive adults in an HIV hyperendemic community of rural South Africa report sexual behaviors consistent with high HIV transmission risk. Older HIV-negative adults report sexual behaviors consistent with high HIV acquisition risk. Prevention initiatives tailored to the particular prevention needs of older adults are urgently needed to reduce HIV risk in this and similar communities in sub-Saharan Africa.The HAALSI study was funded by the NIA of the NIH (P01 AG041710). HAALSI is nested within the Agincourt Health and Socio-Demographic Surveillance System, with funding from Wellcome Trust (058893/Z/99/A; 069683/Z/02/Z; 085477/Z/08/Z; 085477/B/08/Z), University of the Witwatersrand, and Medical Research Council, South Africa. T.W.B. received funding from the Wellcome Trust and NICHD of NIH (R01-HD084233) and NIAID of NIH (R01-AI124389 and R01-AI112339)

Performance of self-reported HIV status in determining true HIV status among older adults in rural South Africa: a validation study

Introduction: In South Africa, older adults make up a growing proportion of people living with HIV. HIV programmes are likely to reach older South Africans in home-based interventions where testing is not always feasible. We evaluate the accuracy of self-reported HIV status, which may provide useful information for targeting interventions or offer an alternative to biomarker testing. Methods: Data were taken from the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) baseline survey, which was conducted in rural Mpumalanga province, South Africa. A total of 5059 participants aged ≥40 years were interviewed from 2014 to 2015. Self-reported HIV status and dried bloodspots for HIV biomarker testing were obtained during at-home interviews. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for self-reported status compared to “gold standard” biomarker results. Log-binomial regression explored associations between demographic characteristics, antiretroviral therapy (ART) status and sensitivity of self-report. Results: Most participants (93%) consented to biomarker testing. Of those with biomarker results, 50.9% reported knowing their HIV status and accurately reported it. PPV of self-report was 94.1% (95% confidence interval (CI): 92.0–96.0), NPV was 87.2% (95% CI: 86.2–88.2), sensitivity was 51.2% (95% CI: 48.2–54.3) and specificity was 99.0% (95% CI: 98.7–99.4). Participants on ART were more likely to report their HIV-positive status, and participants reporting false-negatives were more likely to have older HIV tests. Conclusions: The majority of participants were willing to share their HIV status. False-negative reports were largely explained by lack of testing, suggesting HIV stigma is retreating in this setting, and that expansion of HIV testing and retesting is still needed in this population. In HIV interventions where testing is not possible, self-reported status should be considered as a routine first step to establish HIV status.This study was funded by the National Institute on Aging (NIA) of the National Institutes of Health (NIH) [P01-AG041710] and is nested within the MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt) and funded by Wellcome Trust [058893/Z/99/A; 069683/Z/02/Z; 085477/Z/08/Z; 085477/B/08/Z] with important contributions from the University of the Witwatersrand and the South African Medical Research Council. Till Bärnighausen was supported by the Alexander von Humboldt Foundation through the Alexander von Humboldt Professor award, funded by the German Federal Ministry of Education and Research. He is also supported by the Wellcome Trust, the European Commission, the Clinton Health Access Initiative and NICHD of NIH [R01-HD084233], NIAID of NIH [R01-AI124389 and R01-AI112339] and FIC of NIH [D43-TW009775]

Child and Parent Physical Activity, Sleep, and Screen Time During COVID-19 and Associations With Mental Health: Implications for Future Psycho-Cardiological Disease?

The COVID-19 pandemic has afforded the opportunity for some to improve lifestyle behaviours, while for others it has presented key challenges. Adverse changes in global lifestyle behaviours, including physical activity, sleep, and screen time can affect proximal mental health and in turn distal cardiovascular outcomes. We investigated differences in physical activity, sleep, and screen time in parents and children during early stages of the COVID-19 pandemic in Australia compared to pre-COVID-19 national data; and estimated associations between these movement behaviours with parent and child mental health. Cross-sectional baseline data from the COVID-19 Pandemic Adjustment Study (CPAS; N = 2,365) were compared to nationally representative pre-pandemic data from the Longitudinal Study of Australian Children (LSAC; N = 9,438). Participants were parents of children aged ≤ 18 years, residing in Australia. Parents provided self-report measures of mental health, physical activity and sleep quality, and reported on child mental health, physical activity and screen time. Children in CPAS had significantly more sleep problems and more weekend screen time. Their parents had significantly poorer sleep quality, despite increased weekly physical activity. Children's sleep problems were significantly associated with increased mental health problems, after accounting for socioeconomic status, physical activity, and screen time. Poorer parent sleep quality and lower levels of physical activity were significantly associated with poorer mental health. Monitoring this cohort over time will be important to examine whether changes in movement behaviour are enduring or naturally improve with the easing of restrictions; and whether these changes have lasting effects on either parent or child mental health, and in turn, future risk for CVD