302 research outputs found

    Is arterial stiffening associated with adiposity, severity of obesity and other contemporary cardiometabolic markers in a community sample of adolescents with obesity in the UK?

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    BACKGROUND: Cardiovascular disease (CVD) prediction is problematic within groups of obese adolescents as measures such as adiposity and metabolic markers lack validation. Pulse wave velocity (PWV), a proxy for arterial stiffening, is a potential way to contemporaneously capture adolescents at greater risk of CVD. OBJECTIVES: To investigate associations between PWV and 1) adiposity and 2) other conventional metabolic factors in a community sample of (>95th centile body mass index (BMI)). DESIGN AND SETTING: Cross-sectional measurement and analysis in a hospital-based research centre drawn from a community sample of adolescents recruited to an obesity intervention at baseline. PATIENTS: 174 adolescents (12-19 years) with obesity (>95th centile BMI). 37% were male, while 66 (38%) were white, 53 (30%) black, 36 (21%) South Asian, 19 (11%) mixed/other. Participants with endocrine, genetic causes of obesity and chronic medical conditions (excluding asthma) were excluded. MEASURES: BMI z-score (zBMI), waist z-score, fat mass index (FMI: measured using bioimpedance), sagittal abdominal dimension (SAD), cardiometabolic blood tests and resting blood pressure (BP) were collected. Carotid-radial PWV was measured by a single operator. RESULTS: PWV was associated with age but not pubertal stage. PWV was positively associated with adiposity (zBMI: coefficient 0.44 (95% CI 0.08 to 0.79); FMI: coefficient 0.05 (95% CI 0.00 to 0.10); waist z-score: coefficient 0.27 (95% CI 0.00 to 0.53); SAD: coefficient 0.06 (95% CI: 0.00 to 0.12)). There was no association between PWV and BP, and few associations with cardiometabolic bloods. Associations between PWV and adiposity measures were robust to adjustment in multivariable models except for SAD. Participants with zBMI >2.5 SD and >3.5 SD had greater average PWV but overlap between groups was large. CONCLUSIONS: In our sample, increasing adiposity was positively associated with arterial stiffness, however partitioning by severity was not reliable. Lack of associations between BP, cardiometabolic bloods and arterial stiffness questions the reliability of these factors for predicting CVD risk in adolescents with obesity

    Snell\u27s Law of Refraction Observed in Thermal Frontal Polymerization

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    We demonstrate that Snell’s law of refraction can be applied to thermal fronts propagating through a boundary between regions that support distinct frontal velocities. We use the free-radical frontal polymerization of a triacrylate with clay filler that allows for two domains containing two different concentrations of a peroxide initiator to be molded together. Because the polymerization reaction rates depend on the initiator concentration, the propagation speed is different in each domain. We study fronts propagating in two parallel strips in which the incident angle is 90°. Our data fit Snell’s law vr/vi = sin θr/sin θi, where vr is the refracted velocity, vi is the incident velocity, θr is the angle of refraction, and θi is the incident angle. Further, we study circular fronts propagating radially from an initiation point in a high-velocity region into a low-velocity region (and vice versa). We demonstrate the close resemblance between the numerically simulated and experimentally observed thermal reaction fronts. By measuring the normal velocity and the angle of refraction of both simulated and experimental fronts, we establish that Snell’s law holds for thermal frontal polymerization in our experimental system. Finally we discuss the regimes in which Snell’s law may not be valid

    The effect of climate on lake mixing patterns and temperatures

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    The maritime geographical location has been said to give distinctive characteristics of water mixing to lakes (Hutchinson 1957, pp. 443-444), but such effects have never been described in detail. New Zealand's lakes should exemplify well these maritime distinctions, and in this chapter features of water column mixing and temperature changes are identified which can distinguish New Zealand lakes from those elsewhere

    Child obesity cut-offs as derived from parental perceptions: cross-sectional questionnaire.

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    BACKGROUND: Overweight children are at an increased risk of premature mortality and disease in adulthood. Parental perceptions and clinical definitions of child obesity differ, which may lessen the effectiveness of interventions to address obesity in the home setting. The extent to which parental and objective weight status cut-offs diverge has not been documented. AIM: To compare parental perceived and objectively derived assessment of underweight, healthy weight, and overweight in English children, and to identify sociodemographic characteristics that predict parental under- or overestimation of a child's weight status. DESIGN AND SETTING: Cross-sectional questionnaire completed by parents linked with objective measurement of height and weight by school nurses, in English children from five regions aged 4-5 and 10-11 years old. METHOD: Parental derived cut-offs for under- and overweight were derived from a multinomial model of parental classification of their own child's weight status against school nurse measured body mass index (BMI) centile. RESULTS: Measured BMI centile was matched with parent classification of weight status in 2976 children. Parents become more likely to classify their children as underweight when they are at the 0.8th centile or below, and overweight at the 99.7th centile or above. Parents were more likely to underestimate a child's weight if the child was black or South Asian, male, more deprived, or the child was older. These values differ greatly from the BMI centile cut-offs for underweight (2nd centile) and overweight (85th). CONCLUSION: Clinical and parental classifications of obesity are divergent at extremes of the weight spectrum

    Maximising engagement, motivation and long term change in a Structured Intensive Education Programme in Diabetes for children, young people and their families: Child and Adolescent Structured Competencies Approach to Diabetes Education (CASCADE).

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    BACKGROUND: This trial aims to evaluate effective delivery and cost effectiveness of an innovative structured psycho-educational programme (CASCADE) for young people and their families living with diabetes. The increase in numbers of people being diagnosed with diabetes is posing a challenge for both the UK and the rest of the world. The peak age for diagnosis is between 10 and 14 years of age. There is clear evidence that improved diabetes control from diagnosis in childhood can reduce the incidence and progression of long-term complications. However, despite the development of improved insulin regimens and delivery methods, the overall metabolic control in children and adolescents has improved little in the UK in the past decade. Therefore there is a need for novel interventions and health delivery mechanisms aimed at young people and their families to help improve control and reduce complications, illness burden and costs to the NHS. METHODS/DESIGN: The CASCADE trial is a multi-centre randomised control trial with 26 clinics randomised to control or intervention groups, with 572 children and young people involved in the study. The intervention will be delivered in 4 group sessions, over a 4 month period. A developmentally appropriate curriculum will be delivered to groups of 3 - 4 families, focusing on achievement of increasing competency in self-management of diabetes. The control group will receive standard care from their clinical team, usually consisting of regular 3-monthly clinic visits and telephone contact as required with the clinical nurse specialist and consultant. The primary outcomes of the trial will be change in HbA1c between baseline and 12 months and 24 months post recruitment. Secondary outcomes will include measures related to the economic evaluation, psychosocial outcomes, outcomes related to management of diabetes outcomes, and adherence to the intervention. DISCUSSION: The trial will be run by independent research and service delivery teams and supervised by a trial steering committee. A data monitoring and ethics committee has been put in place to monitor the trial and recommend stopping/continuation according to a Peto-Haybittle rule. The trial will be conducted according to the principles of MRC Good Clinical Practice (GCP) Guidelines and CTRU Phase III Trial Standard Operating procedures. TRIAL REGISTRATION: Current Controlled Trials ISRCTN52537669

    Reopening schools during the COVID-19 pandemic: governments must balance the uncertainty and risks of reopening schools against the clear harms associated with prolonged closure.

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    Evidence to support the effectiveness of global school closures in controlling COVID-19 is sparse. There is continued uncertainty about the degree to which school children are susceptible to and transmit COVID-19. Balancing the potential benefits with harms involves explicit trade-offs for governments, but there has been little recognition that low-income and middle-income countries face a very different set of trade-offs around school reopening from those in wealthy countries

    The Discovery of Comparative Advantage

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    Torrens [in 1815] clearly preceded Ricardo [in 1817] in publishing a fairly satisfactory formulation of the doctrine [of comparative costs]. It is unquestionable, however that Ricardo is entitled to the credit for first giving due emphasis to the doctrine, for first placing it an appropriate setting, and for obtainin

    Effectiveness of a structured educational intervention using psychological delivery methods in children and adolescents with poorly controlled type 1 diabetes: a cluster-randomized controlled trial of the CASCADE intervention.

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    INTRODUCTION: Type 1 diabetes (T1D) in children and adolescents is increasing worldwide with a particular increase in children <5 years. Fewer than 1 in 6 children and adolescents achieve recommended glycated hemoglobin (HbA1c) values. METHODS: A pragmatic, cluster-randomized controlled trial assessed the efficacy of a clinic-based structured educational group incorporating psychological approaches to improve long-term glycemic control, quality of life and psychosocial functioning in children and adolescents with T1D. 28 pediatric diabetes services were randomized to deliver the intervention or standard care. 362 children (8-16 years) with HbA1c≥8.5% were recruited. Outcomes were HbA1c at 12 and 24 months, hypoglycemia, admissions, self-management skills, intervention compliance, emotional and behavioral adjustment, and quality of life. A process evaluation collected data from key stakeholder groups in order to evaluate the feasibility of delivering the intervention. RESULTS: 298/362 patients (82.3%) provided HbA1c at 12 months and 284/362 (78.5%) at 24 months. The intervention did not improve HbA1c at 12 months (intervention effect 0.11, 95% CI -0.28 to 0.50, p=0.584), or 24 months (intervention effect 0.03, 95% CI -0.36 to 0.41, p=0.891). There were no significant changes in remaining outcomes. 96/180 (53%) families in the intervention arm attended at least 1 module. The number of modules attended did not affect outcome. Reasons for low uptake included difficulties organizing groups and work and school commitments. Those with highest HbA1cs were less likely to attend. Mean cost of the intervention was £683 per child. CONCLUSIONS: Significant challenges in the delivery of a structured education intervention using psychological techniques to enhance engagement and behavior change delivered by diabetes nurses and dietitians in routine clinical practice were found. The intervention did not improve HbA1c in children and adolescents with poor control. TRIAL REGISTRATION NUMBER: ISRCTN52537669, results

    Cost-effectiveness of a community-delivered multicomponent intervention compared with enhanced standard care of obese adolescents: cost-utility analysis alongside a randomised controlled trial (the HELP trial)

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    Objective To undertake a cost-utility analysis of a motivational multicomponent lifestyle-modification intervention in a community setting (the Healthy Eating Lifestyle Programme (HELP)) compared with enhanced standard care. Design Cost-utility analysis alongside a randomised controlled trial. Setting Community settings in Greater London, England. Participants 174 young people with obesity aged 12–19 years. Interventions Intervention participants received 12 one to-one sessions across 6months, addressing lifestyle behaviours and focusing on motivation to change and self esteem rather than weight change, delivered by trained graduate health workers in community settings. Control participants received a single 1-hour one-to-one nurse delivered session providing didactic weight-management advice. Main outcome measures Mean costs and quality adjusted life years (QALYs) per participant over a 1-year period using resource use data and utility values collected during the trial. Incremental cost-effectiveness ratio (ICER) was calculated and non-parametric bootstrapping was conducted to generate a cost-effectiveness acceptability curve (CEAC). Results Mean intervention costs per participant were £918 for HELP and £68 for enhanced standard care. There were no significant differences between the two groups in mean resource use per participant for any type of healthcare contact. Adjusted costs were significantly higher in the intervention group (mean incremental costs for HELP vs enhanced standard care £1003 (95% CI £837 to £1168)). There were no differences in adjusted QALYs between groups (mean QALYs gained 0.008 (95% CI −0.031 to 0.046)). The ICER of the HELP versus enhanced standard care was £120 630 per QALY gained. The CEAC shows that the probability that HELP was cost-effective relative to the enhanced standard care was 0.002 or 0.046, at a threshold of £20 000 or £30 000 per QALY gained. Conclusions We did not find evidence that HELP was more effective than a single educational session in improving quality of life in a sample of adolescents with obesity. HELP was associated with higher costs, mainly due to the extra costs of delivering the intervention and therefore is not cost-effective

    Liquor licences issued to Australian schools

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    BACKGROUND: Children's positive socialisation to alcohol is associated with early initiation of drinking and alcohol-related harm in adult life. Internationally, there have been reports of adults' alcohol consumption at school events in the presence of children. The aim of this research was to identify the conditions under which Australian schools are required to apply for a liquor licence and the associated prevalence of liquor licences for these events where children were likely to be present. METHODS: A document review was conducted to examine temporary liquor licensing legislation. Quantitative analysis was used to examine relevant licensing data. Coding criteria was developed to determine school type, student year levels and the likely presence of children. RESULTS: Four jurisdictions provided data on 1817 relevant licences. The average annual licences/100 schools was highest amongst Independent schools followed by Catholic and public (government) schools. The rates were highest in Queensland and Victoria where children were present at 61% and 32% of events respectively. CONCLUSIONS: While there are legislative differences across jurisdictions, the prevalence of adults' alcohol use at school events in the presence of children may reflect the various education department policies and principals' and school communities' beliefs and attitudes. Licences are not required for all events where liquor is consumed so the prevalence of adults' use of alcohol at school events is likely to be higher than our analyses imply. Such practices may undermine teaching about alcohol use in the school curriculum and health promotion efforts to develop alcohol-free events when children are present
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