65 resultados para Course of study


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We present for the first time a real-time small-angle X-ray scattering (SAXS) study of the structural transition of fluid microemulsion to solid polymerized material in a silicone polymerizable microemulsion system. A reactive methacrylate-terminated siloxane macromonomer (MTSM, Mn ∼ 1000 g/mol) was synthesized and used for microemulsion formulations comprising MTSM (oil phase), water, and a mixture of nonionic surfactant (Teric G9A8) with isopropanol. In situ synchrotron SAXS was used to investigate time-dependent nanostructure evolution during the polymerization reaction, which was directly initiated by X-ray radiation. The SAXS data were analyzed using both the Teubner-Strey model and the core-shell model. The results obtained by the Teubner-Strey model showed that the domain size (d) decreased while the correlation length (ξ) increased upon polymerization. The analysis in terms of the core-shell model displayed that adding water to the precursor microemulsion caused the water droplets to start swelling, which resulted in the discontinuity of water in oil microemulsion. There exhibited large differences in morphologies of polymerized materials from the microemulsion formulations with different water and surfactant contents. The core and shell sizes of water droplets decreased during the course of polymerization when there was 15 wt % or more water in the microemulsion formulation; the polymerized material thus exhibited increasingly discrete granular morphology. When there was 10 wt % or less water content in the precursor microemulsion, the rearrangement of water domains could be minimized during the course of polymerization and transparent polymerized material was obtained.

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Background Knowledge about the natural history of self-harm is scarce, especially during the transition from adolescence to young adulthood, a period characterised by a sharp rise in self-inflicted deaths. From a repeated measures cohort of a representative sample, we describe the course of self-harm from middle adolescence to young adulthood.

Methods A stratified, random sample of 1943 adolescents was recruited from 44 schools across the state of Victoria, Australia, between August, 1992, and January, 2008. We obtained data pertaining to self-harm from questionnaires and telephone interviews at seven waves of follow-up, commencing at mean age 15·9 years (SD 0·49) and ending at mean age 29·0 years (SD 0·59). Summary adolescent measures (waves three to six) were obtained for cannabis use, cigarette smoking, high-risk alcohol use, depression and anxiety, antisocial behaviour and parental separation or divorce.

Findings 1802 participants responded in the adolescent phase, with 149 (8%) reporting self-harm, More girls (95/947 [10%]) than boys (54/855 [6%]) reported self-harm (risk ratio 1·6, 95% CI 1·2–2·2). We recorded a substantial reduction in the frequency of self-harm during late adolescence. 122 of 1652 (7%) participants who reported self-harm during adolescence reported no further self-harm in young adulthood, with a stronger continuity in girls (13/888) than boys (1/764). During adolescence, incident self-harm was independently associated with symptoms of depression and anxiety (HR 3·7, 95% CI 2·4–5·9), antisocial behaviour (1·9, 1·1–3·4), high-risk alcohol use (2·1, 1·2–3·7), cannabis use (2·4, 1·4–4·4), and cigarette smoking (1·8, 1·0–3·1). Adolescent symptoms of depression and anxiety were clearly associated with incident self-harm in young adulthood (5·9, 2·2–16).

Interpretation Most self-harming behaviour in adolescents resolves spontaneously. The early detection and treatment of common mental disorders during adolescence might constitute an important and hitherto unrecognised component of suicide prevention in young adults.

Funding National Health and Medical Research Council, Australia, and operational infrastructure support programme, Government of Victoria, Australia.

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BACKGROUND: Childhood obesity has reached epidemic proportions in developed countries. Sedentary screen-based activities such as video gaming are thought to displace active behaviors and are independently associated with obesity. Active video games, where players physically interact with images onscreen, may have utility as a novel intervention to increase physical activity and improve body composition in children. The aim of the Electronic Games to Aid Motivation to Exercise (eGAME) study is to determine the effects of an active video game intervention over 6 months on: body mass index (BMI), percent body fat, waist circumference, cardio-respiratory fitness, and physical activity levels in overweight children.

METHODS/DESIGN: Three hundred and thirty participants aged 10-14 years will be randomized to receive either an active video game upgrade package or to a control group (no intervention).

DISCUSSION: An overview of the eGAME study is presented, providing an example of a large, pragmatic randomized controlled trial in a community setting. Reflection is offered on key issues encountered during the course of the study. In particular, investigation into the feasibility of the proposed intervention, as well as robust testing of proposed study procedures is a critical step prior to implementation of a large-scale trial.

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Tradition and modernisation are often seen as a binary opposition. In an urban environment, traditional built form seems incompatible to modern way of life, and the adaptation of traditional neighbourhoods to modern use often causes controversy. Nowadays, ideas about ‘what is tradition’ become shifting, and traditional townscape does not necessarily mean an obstacle to modernisation. This paper reveals how the role of traditional elements is played in China’s urban development. The case study of Xintiandi, Shanghai, where traditional townscape is restored, highlights the connection of the city’s past and present. Xintiandi is a successful yet controversial city renewal project, where Shanghai’s traditional housing form Shikumen is restored and put into adaptive uses. In the course of urban modernisation, the role of tradition as a representation of the connection between the city’s past and present deserves more study. This paper aims to add a perspective to the literature on the study of tradition. It argues for the diversity and fluidity of the ideas about tradition., In this view, tradition is not necessarily in dichotomy with, or opposite to modernisation; rather, tradition justifies the needs of modernisation and supplements its outcomes. The paper is developed in light of works on tradition by Shils, Hobsbawm, Giddens and others; The case study of Xintiandi shows what Old Shanghai tradition means to this city today, and how traditional elements are adapted and used in the course of urban modernisation.

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BACKGROUND: This study aimed to explore the course of depression and anxiety in chronic hepatitis C patients. METHODS:   Data were combined from two studies: (1) Hospital Anxiety and Depression Scale (HADS) scores in 395 consecutive Australian outpatients from 2006 to 2010 formed the baseline measurement; and (2) Depression Anxiety Stress Scales (DASS) scores in a survey of a sub-sample of these patients in 2011 formed the follow-up measurement. After converting DASS to HADS scores, changes in symptom scores and rates of case-ness (≥8), and predictors of follow-up symptoms were assessed. RESULTS:   Follow-up data were available for 61 patients (70.5% male) whose age ranged from 24.5 to 74.6 years (M=45.6). The time to follow-up ranged from 20.7 to 61.9 months (M=43.8). Baseline rates of depression (32.8%) and anxiety (44.3%) increased to 62.3% and 67.2%, respectively. These findings were confirmed, independent of the conversion, by comparing baseline HADS and follow-up DASS scores with British community norms. Baseline anxiety and younger age predicted depression, while baseline anxiety, high school non-completion, and single relationship status predicted anxiety. CONCLUSION:  This study demonstrated a worsening trajectory of depression and anxiety. Further controlled and prospective research in a larger sample is required to confirm these findings.