A Multi-Level Investigation of Factors Predicting the Health of Adolescents Attending a Faith-Based School System in Australia

Adolescent health is a major worldwide concern and is central to a number of current global health challenges. There is growing awareness that the factors influencing adolescent health are multi-dimensional and encompass a broad network of interrelated determinants. Although studies have explored the influence of selected determinants on adolescent health, few have explored the relative importance of the various determinants and the relationships that exist between them. Using Structural Equation Modelling (SEM), this thesis empirically investigates the complex network of factors that concomitantly predict health behaviours and health outcomes in adolescents. The thesis centres on data collected from a comprehensive health and lifestyle survey administered to 1734 adolescents (mean age = 14.5 ± 1.6 years; 54% males) attending 21 Seventh-day Adventist (Adventist) schools in Australia. The research findings are presented as a coherent series of five studies for publication in peer reviewed journals. Study 1 focused on the self-rated health (SRH) status of the adolescents and investigated the association of a multitude of determinants including personal demographics; background factors such as childhood family dynamics (CFD) and adverse childhood experiences (ACEs); and selected health behaviours and health measures. The findings of Study 1 confirmed the complex relationship between these determinants and highlighted their respective relationships. Particularly noteworthy in this study was the relative high degree of association of mental health, body mass index (BMI) and ACEs on SRH. The findings from Study 1 formed the basis for Studies 2 to 5 which more extensively explored particular aspects of the model developed in Study 1. Extending upon the observation in Study 1 of the significant influence of mental health status on the SRH of the adolescents, Study 2 examined the predictors of mental health in greater detail. The model developed in Study 2 through SEM analyses revealed that CFD was the strongest predictor of the adolescents’ mental health status, followed by having a sense of meaning and purpose, perceived social rejection and school academic performance. Multi-group analysis for gender found significant differences. The mental health of males was more greatly affected by physical activity, whereas the mental health of females was more greatly affected by sleep duration. Another significant finding of Study 1 was the influence of BMI, a measure of overweight and obesity, on SRH and this formed the focus of Study 3. Compared to national norms, lower rates of overweight and obesity but higher rates of underweight were observed in the study, which was explained by the unique characteristics of the school system the study cohort was drawn from. BMI was lower among the young members of the cohort, as well as those who more regularly ate breakfast, consumed less soft drink and had a regular exercise program. In Study 1, alcohol consumption was not significantly associated with self-rated health; however, a low rate of alcohol consumption was observed among the study cohort. Study 4, therefore, aimed to better understand the factors influencing alcohol consumption among this unique cohort. The findings of Study 4 indicated that adolescents’ intentions to consume alcohol were the greatest predictor of alcohol consumption. Consistent with the Theory of Reasoned Action, intentions to consume alcohol was influenced by their attitudes towards alcohol consumption and subjective norms surrounding alcohol consumption. Finally, Study 5 focused on the unique faith-based aspect of the cohort to ascertain the influence of religious affiliation on the various health behaviours and health outcomes examined in Studies 1–4. The study found that adolescents who identified themselves as Adventist (57% of the total cohort) reported significantly better health behaviours than the other Christian and non-religious adolescents. This was especially significant among older adolescents (16–18 years). However, these better health behaviours did not translate to improved health status. The findings from this thesis provide for the first time, a comprehensive picture of the complex network of factors associated with the health outcomes of adolescents attending Adventist schools in Australia. The findings support the need for age and gender appropriate multi-component interventions and prevention initiatives to promote positive health outcomes in adolescents, with an emphasis on prioritising not only modifiable health behaviours but upstream factors such as CFD and ACEs

Three papers on the Development and Contribution of Ideational Frameworks in Russian Politics, 1917-1934 and 1991-2008

The central contention of this dissertation is that political scientists have largely ignored the importance of ideational frameworks for resolving problems of policy-making in times of significant upheaval. In order to illustrate the genesis and contribution of these frameworks, the three papers in my dissertation focus on a diachronic comparison of two moments in Russian history that encapsulate maximal uncertainty, covering the aftermath of the imperial collapses in 1917 and 1991. The first paper focuses on state- and nation-building in the North Caucasus, arguing that the debates between the Bolsheviks and other members of the Second International, particularly Otto Bauer, provided the Bolsheviks with a coherent platform that could largely stem the fissiparous tendencies of the region in a way that Boris Yeltsin and his teams were unable to do in the early 1990s. The second paper examines economic policy and finds the reverse to be true: the economic debates of the Second International largely ignored the problem of the peasantry and the exiled status of many of the leading Bolsheviks meant they were unable to articulate a sufficiently detailed policy to apply to the Russian case. The post-communists under the leadership of Yegor Gaidar, were able to draw on decades of economic research, particularly the Chicago and Virginia Schools, that provided the intellectual rationale for dismembering the Communist command-system, but equally important was the years that Gaidar and his team spent developing an alternative in the twilight years of communism. The final paper considers the legacy of ideational frameworks by considering the rule of Stalin and Putin, arguing that the tasks left unfulfilled provide a basis for regime consolidation by subsequent rulers.Governmen

Preventing type 2 diabetes: systematic review of studies of cost-effectiveness of lifestyle programmes and metformin, with and without screening, for pre-diabetes

Objective Explore the cost-effectiveness of lifestyle interventions and metformin in reducing subsequent incidence of type 2 diabetes, both alone and in combination with a screening programme to identify high-risk individuals. Design Systematic review of economic evaluations. Data sources and eligibility criteria Database searches (Embase, Medline, PreMedline, NHS EED) and citation tracking identified economic evaluations of lifestyle interventions or metformin alone or in combination with screening programmes in people at high risk of developing diabetes. The International Society for Pharmaco-economics and Outcomes Research’s Questionnaire to Assess Relevance and Credibility of Modelling Studies for Informing Healthcare Decision Making was used to assess study quality. Results 27 studies were included; all had evaluated lifestyle interventions and 12 also evaluated metformin. Primary studies exhibited considerable heterogeneity in definitions of pre-diabetes and intensity and duration of lifestyle programmes. Lifestyle programmes and metformin appeared to be cost effective in preventing diabetes in high-risk individuals (median incremental cost-effectiveness ratios of £7490/quality-adjusted life-year (QALY) and £8428/QALY, respectively) but economic estimates varied widely between studies. Intervention-only programmes were in general more cost effective than programmes that also included a screening component. The longer the period evaluated, the more cost-effective interventions appeared. In the few studies that evaluated other economic considerations, budget impact of prevention programmes was moderate (0.13%–0.2% of total healthcare budget), financial payoffs were delayed (by 9–14 years) and impact on incident cases of diabetes was limited (0.1%–1.6% reduction). There was insufficient evidence to answer the question of (1) whether lifestyle programmes are more cost effective than metformin or (2) whether low-intensity lifestyle interventions are more cost effective than the more intensive lifestyle programmes that were tested in trials. Conclusions The economics of preventing diabetes are complex. There is some evidence that diabetes prevention programmes are cost effective, but the evidence base to date provides few clear answers regarding design of prevention programmes because of differences in denominator populations, definitions, interventions and modelling assumption

The Influence of Three Modes of Human Support on Attrition and Adherence to a Web- and Mobile App–Based Mental Health Promotion Intervention in a Nonclinical Cohort: Randomized Comparative Study

Background: The escalating prevalence of mental health disorders necessitates a greater focus on web- and mobile app–based mental health promotion initiatives for nonclinical groups. However, knowledge is scant regarding the influence of human support on attrition and adherence and participant preferences for support in nonclinical settings. Objective: This study aimed to compare the influence of 3 modes of human support on attrition and adherence to a digital mental health intervention for a nonclinical cohort. It evaluated user preferences for support and assessed whether adherence and outcomes were enhanced when participants received their preferred support mode. Methods: Subjects participated in a 10-week digital mental health promotion intervention and were randomized into 3 comparative groups: standard group with automated emails (S), standard plus personalized SMS (S+pSMS), and standard plus weekly videoconferencing support (S+VCS). Adherence was measured by the number of video lessons viewed, points achieved for weekly experiential challenge activities, and the total number of weeks that participants recorded a score for challenges. In the postquestionnaire, participants ranked their preferred human support mode from 1 to 4 (S, S+pSMS, S+VCS, S+pSMS & VCS combined). Stratified analysis was conducted for those who received their first preference. Preintervention and postintervention questionnaires assessed well-being measures (ie, mental health, vitality, depression, anxiety, stress, life satisfaction, and flourishing). Results: Interested individuals (N=605) enrolled on a website and were randomized into 3 groups (S, n=201; S+pSMS, n=202; S+VCS, n=201). Prior to completing the prequestionnaire, a total of 24.3% (147/605) dropped out. Dropout attrition between groups was significantly different (P=.009): 21.9% (44/201) withdrew from the S group, 19.3% (39/202) from the S+pSMS group, and 31.6% (64/202) from the S+VCS group. The remaining 75.7% (458/605) registered and completed the prequestionnaire (S, n=157; S+pSMS, n=163; S+VCS, n=138). Of the registered participants, 30.1% (138/458) failed to complete the postquestionnaire (S, n=54; S+pSMS, n=49; S+VCS, n=35), but there were no between-group differences (P=.24). For the 69.9% (320/458; S, n=103; S+pSMS, n=114; S+VCS, n=103) who completed the postquestionnaire, no between-group differences in adherence were observed for mean number of videos watched (P=.42); mean challenge scores recorded (P=.71); or the number of weeks that challenge scores were logged (P=.66). A total of 56 participants (17.5%, 56/320) received their first preference in human support (S, n=22; S+pSMS, n=26; S+VCS, n=8). No differences were observed between those who received their first preference and those who did not with regard to video adherence (P=.91); challenge score adherence (P=.27); or any of the well-being measures including, mental health (P=.86), vitality (P=.98), depression (P=.09), anxiety (P=.64), stress (P=.55), life satisfaction (P=.50), and flourishing (P=.47). Conclusions: Early dropout attrition may have been influenced by dissatisfaction with the allocated support mode. Human support mode did not impact adherence to the intervention, and receiving the preferred support style did not result in greater adherence or better outcomes. Trial Registration: Australian New Zealand Clinical Trials Registry (ANZCTR): 12619001009101; http://www.anzctr.org.au/ACTRN12619001009101.asp

The Influence of Human Support on the Effectiveness of an Online Mental Wellbeing Intervention

Purpose: To compare the influence of three modes of human support on the outcomes of an online, lifestyle-focused mental health promotion intervention. Background: There is a need for efficacious lifestyle interventions to promote the mental wellbeing of both healthy and clinical cohorts. Evidence regarding the usefulness of adding human support (i.e. guidance) to improve the outcomes of online interventions for clinical populations is mixed,1-3 however little is known about healthy cohorts. Methods: A total of 458 participants self-selected to participate in a 10-week online, multimodal lifestyle intervention that addressed mental wellbeing. The participants were randomized into three groups, differentiated by support mode: standard - automated emails only (S); standard plus personalised SMS messages (S+pSMS); standard plus videoconference support (S+VCS). At pre- and post-intervention, the participants completed the following measures: the ‘mental health’ and ‘vitality’ sub-scales from the Short Form Health Survey (SF-36); Depression Anxiety and Stress Scales (DASS-21); Satisfaction With Life (SWL) scale; and Flourishing scale. Results: A total of 320 participants (S, n=103; S+pSMS, n=114; S+VCS, n=103) completed the study. Significant within-group changes were recorded from pre- to post-intervention in all groups for every outcome measure (PP=0.77), vitality (P=0.65), depression (P=0.93), anxiety (P=0.25), stress (P=0.57), SWL (P=0.65) or flourishing (P=0.99). Attendance at the weekly videoconference support sessions was poor, but those who attended seven or more of the ten sessions experienced significantly better outcomes in mental health (P=.006, d=0.71), vitality (P=.005, d=0.73), depression (P=.04, d=0.54), and SWL (P=.046, d=0.50), than those who attended less than seven. Conclusions: A lifestyle-focused, online mental health promotion intervention enhanced measures of mental wellbeing among a healthy cohort, irrespective of the human support provided. Supplementing a psychological intervention with videoconference support might improve outcomes, when attendance is optimised

In situ Rb-Sr dating by collision cell, multicollection inductively-coupled plasma mass-spectrometry with pre-cell mass-filter, (CC-MC-ICPMS/MS)

We document the utility for in situ Rb–Sr dating of a one-of-a-kind tribrid mass spectrometer, ‘Proteus’, coupled to a UV laser ablation system. Proteus combines quadrupole mass-filter, collision cell and sector magnet with a multicollection inductively-coupled plasma mass spectrometer (CC-MC-ICPMS/MS). Compared to commercial, single collector, tribrid inductively-coupled plasma mass spectrometers (CC-ICPMS/MS) Proteus has enhanced ion transmission and offers simultaneous collection of all Sr isotopes using an array of Faraday cups. These features yield improved precision in measured (87)Sr/(86)Sr ratios, for a given mass of Sr analysed, approximately a factor of 25 in comparison to the Thermo Scientific™ iCAP TQ™ operated under similar conditions. Using SF(6) as a reaction gas on Proteus, measurements of Rb-doped NIST SRM (standard reference material) 987 solutions, with Rb/Sr ratios from 0.01–100, yield (87)Sr/(86)Sr that are indistinguishable from un-doped NIST SRM 987, demonstrating quantitative ‘chemical resolution’ of Rb from Sr. We highlight the importance of mass-filtering before the collision cell for laser ablation (87)Sr/(86)Sr analysis, using an in-house feldspar standard and a range of glass reference materials. By transmitting only those ions with mass-to-charge ratios 82–92 u/e into the collision cell, we achieve accurate (87)Sr/(86)Sr measurements without any corrections for atomic or polyatomic isobaric interferences. Without the pre-cell mass-filtering, measured in situ(87)Sr/(86)Sr ratios are inaccurate. Combining in situ measurements of Rb/Sr and radiogenic Sr isotope ratios we obtain mineral isochrons. We utilise a sample from the well-dated Dartmoor granite (285 ± 1 Ma) as a calibrant for our in situ ages and, using the same conditions, produce accurate Rb–Sr isochron ages for samples of the Fish Canyon tuff (28 ± 2 Ma) and Shap granite pluton (397 ± 1 Ma). Analysing the same Dartmoor granite sample using identical laser conditions and number of spot analyses using the Thermo Scientific™ iCAP TQ™ yielded an isochron slope 5× less precise than Proteus. We use an uncertainty model to illustrate the advantage of using Proteus over single collector CC-ICPMS/MS for in situ Rb–Sr dating. The results of this model show that the improvement is most marked for samples that have low Rb/Sr (<10) or are young (<100 Ma). We also report the first example of an in situ, internal Rb–Sr isochron from a single potassium-feldspar grain. Using a sample from the Shap granite, we obtained accurate age and initial (87)Sr/(86)Sr with 95% confidence intervals of ±1.5% and ±0.03% respectively. Such capabilities offer new opportunities in geochronological studies

Chemical formation of hybrid di-nitrogen calls fungal codenitrification into question

Removal of excess nitrogen (N) can best be achieved through denitrification processes that transform N in water and terrestrial ecosystems to di-nitrogen (N-2) gas. The greenhouse gas nitrous oxide (N2O) is considered an intermediate or end-product in denitrification pathways. Both abiotic and biotic denitrification processes use a single N source to form N2O. However, N-2 can be formed from two distinct N sources (known as hybrid N-2) through biologically mediated processes of anammox and codenitrification. We questioned if hybrid N-2 produced during fungal incubation at neutral pH could be attributed to abiotic nitrosation and if N2O was consumed during N-2 formation. Experiments with gas chromatography indicated N-2 was formed in the presence of live and dead fungi and in the absence of fungi, while N2O steadily increased. We used isotope pairing techniques and confirmed abiotic production of hybrid N-2 under both anoxic and 20% O-2 atmosphere conditions. Our findings question the assumptions that (1) N2O is an intermediate required for N-2 formation, (2) production of N-2 and N2O requires anaerobiosis, and (3) hybrid N-2 is evidence of codenitrification and/ or anammox. The N cycle framework should include abiotic production of N-2

Factors Predicting the Mental Health of Adolescents Attending a Faith-based Australian School System: A Multi-group Structural Equation Analysis

Background: Adolescents attending Seventh-day Adventist schools (Adventist) in Australia tend to experience good health and exhibit better health behaviors than national norms, however few studies have investigated factors predicting their mental health. Aims: The aim of this study was to explore the complex network of factors that predict the mental health status (MHS) of adolescents attending Adventist schools in Australia. Methods: A survey instrument was used to collect data from 1527 secondary school students attending Adventist schools across Australia. Structural equation modeling was employed to examine concomitantly the direct and indirect effects of childhood experiences, present attitudes and selected health behaviors on MHS. Results: Childhood family dynamics had the strongest association with MHS (βtotal = 0.33) followed by a sense of meaning and purpose (βtotal = 0.27), perceived social misfit status (βtotal = –0.19), and school academic performance (βtotal = 0.18). Multi-group analysis found significant pathway differences in the model for gender with regards to the association of meaning and purpose, physical activity and sleep quantity with MHS. Conclusions: The outcomes of the study highlight the importance of early positive childhood family dynamics and the discovery of meaning and purpose during adolescence to promote positive mental health among adolescents

UK Large-scale Wind Power Programme from 1970 to 1990: the Carmarthen Bay experiments and the Musgrove Vertical-Axis Turbines

This article describes the development of the Musgrove Vertical Axis Wind Turbine (VAWT) concept, the UK ‘Carmarthen Bay’ wind turbine test programme, and UK government’s wind power programme to 1990. One of the most significant developments in the story of British wind power occurred during the 1970s, 1980s, and 1990s, with the development of the Musgrove vertical axis wind turbine and its inclusion within the UK Government’s wind turbine test programme. Evolving from a supervisor’s idea for an undergraduate project at Reading University, the Musgrove VAWT was once seen as an able competitor to the horizontal axis wind systems that were also being encouraged at the time by both the UK government and the Central Electricity Generating Board, the then nationalised electricity utility for England and Wales. During the 1980s and 1990s the most developed Musgrove VAWT system, along with three other commercial turbine designs was tested at Carmarthen Bay, South Wales as part of a national wind power test programme. From these developmental tests, operational data was collected and lessons learnt, which were incorporated into subsequent wind power operations.http://dx.doi.org/10.1260/03095240677860621