Vibration of thick plates using finite strip-elements

This paper develops a finite strip-element method for the vibration analysis of thick plates. The method uses a combined polynomial and trigonometric interpolation scheme that enables all boundary conditions to be correctly treated. The global equations are derived in the usual manner of the finite element method, and natural frequencies of vibration can be found by solving a linear eigenvalue problem

Relationships between the home environment and physical activity and dietary patterns of preschool children: a cross-sectional study

Objective: To assess relationships between characteristics of the home environment and preschool children's physical activity and dietary patterns. Methods: Homes of 280 preschool children were visited and information obtained by direct observation and parent interview regarding physical and nutritional characteristics of the home environment. Children's physical activity, sedentary behaviour and dietary patterns were measured using standardised parent-report questionnaires. Associations were analysed using analysis of variance and correlation. Results: Parental physical activity (p = 0.03–0.008), size of backyard (p = 0.001) and amount of outdoor play equipment (p = 0.003) were associated with more outdoor play. Fewer rules about television viewing (p < 0.001) and presence of playstation (p = 0.02) were associated with more indoor sedentary time. Higher fruit and vegetable intake was associated with restricting children's access to fruit juice (p = 0.02) and restricting high fat/sugar snacks (p = 0.009). Lower intake of noncore foods was associated with restricting children's access to fruit juice (p = 0.007), cordial/ carbonated drinks (p < 0.001) and high fat/sugar snacks (p = 0.003). Lower fruit and vegetable intake was associated with reminding child to 'eat up' (p = 0.007) and offering food rewards to eat main meal (p = 0.04). Higher intake of non-core foods was associated with giving food 'treats' (p = 0.03) and offering food rewards to eat main meal (p = 0.04). The availability of food groups in the home was associated with children's intake of these foods (fruit and vegetables, p < 0.001; fat in dairy, p = <0.001; sweetened beverages, p = 0.004–<0.001; non-core foods, p = 0.01–<0.001). Conclusion: Physical attributes of the home environment and parental behaviours are associated with preschool children's physical activity, sedentary behaviour and dietary patterns. Many of these variables are modifiable and could be targeted in childhood obesity prevention and management.Nicola J Spurrier, Anthea A Magarey, Rebecca Golley, Fiona Curnow and Michael G Sawye

Comparing the nutritional impact of dietary strategies to reduce discretionary choice intake in the Australian adult population: a simulation modelling study

Published: 3 May 2017. Corrected by: Erratum: Grieger, J.A.; et al.: Comparing the Nutritional Impact of Dietary Strategies to Reduce Discretionary Choice Intake in the Australian Adult Population: A Simulation Modelling Study. Nutrients 2017, 9, 442, in Vol. 9, Issue 8, 851. There was anerror in the median intake ratio calculation used in the substitution strategies. The median intake ratios have been corrected throughout Supplementary Table S1. The corrected calculations have led to minor changes (i.e., less than 5% change in nutrient intakes) to results reported in the abstract (page 1), the substitution results text (page 8 and 9), tables and figures (Table 2, columns 4 and 5, page 8; Figure 1, light green and dark green bars, page 6; Figure 2, green bars page 7; Supplementary Table S1, substitution replacement rows; Supplementary Table S3, columns 4–8; and Supplementary Table S6, columns 2 and 3). The corrected tables and text are shown below. These changes have no material impact on the conclusions of our paper. We apologize for any inconvenience caused. The manuscript will be updated and the original will remain online on the article website.Dietary strategies to reduce discretionary choice intake are commonly utilized in practice, but evidence on their relative efficacy is lacking. The aim was to compare the potential impact on nutritional intake of three strategies to reducing discretionary choices intake in the Australian adult (19–90 years) population. Dietary simulation modelling using data from the National Nutrition and Physical Activity Survey 2011–2012 was conducted (n = 9341; one 24 h dietary recall). Strategies modelled were: moderation (reduce discretionary choices by 50%, with 0%, 25% or 75% energy compensation); substitution (replace 50% of discretionary choices with core choices); reformulation (replace 50% SFA with unsaturated fats, reduce added sugars by 25%, and reduce sodium by 20%). Compared to the base case (observed) intake, modelled intakes in the moderation scenario showed: −17.3% lower energy (sensitivity analyses, 25% energy compensation −14.2%; 75% energy compensation −8.0%), −20.9% lower SFA (−17.4%; −10.5%), −43.3% lower added sugars (−41.1%; −36.7%) and 17.7% lower sodium (−14.3%; −7.5%). Substitution with a range of core items, or with fruits, vegetables and core beverages only, resulted in similar changes in energy intake (−13.5% and −15.4%), SFA (−17.7% and −20.1%), added sugars (−42.6% and −43%) and sodium (−13.7% and −16.5%), respectively. Reformulating discretionary choices had minimal impact on reducing energy intake but reduced SFA (−10.3% to −30.9%), added sugars (−9.3% to −52.9%), and alcohol (−25.0% to −49.9%) and sodium (−3.3% to −13.2%). The substitution and reformulation scenarios minimized negative changes in fiber, protein and micronutrient intakes. While each strategy has strengths and limitations, substitution of discretionary choices with core foods and beverages may optimize the nutritional impact.Jessica A. Grieger, Brittany J. Johnson, Thomas P. Wycherley and Rebecca K. Golle

Pairwise approach for analysis and reporting of child’s free sugars intake from a birth cohort study

Objectives: The prospective cohort design is an important research design, but a common challenge is missing data. The purpose of this study is to compare three approaches to managing missing data, the pairwise (n = 1386 children), the partial or modified pairwise (n = 1019) and the listwise (n = 546), to characterize the trajectories of children's free sugars intake (FSI) across early childhood. Methods: By applying the Group-based Trajectory Model Technique to three waves of data collected from a prospective cohort study of South Australian children, this study examined the three approaches in managing missing data to validate and discuss children's FSI trajectories. Results: Each approach identified three distinct trajectories of child's FSI from 1 to 5 years of age: (1) ‘low and fast increasing’, (2) ‘moderate and increasing’ and (3) ‘high and increasing’. The trajectory memberships were consistent across the three approaches, and were for the pairwise scenario (1) 15.1%, (2) 68.3% and (3) 16.6%; the partial or modified pairwise (1) 15.9%, (2) 64.1% and (3) 20.0%; and the listwise (1) 14.9%, (2) 64.9% and (3) 20.2% of children. Conclusions: Given the comparability of the findings across the analytical approaches and the samples' characteristics between baseline and across different data collection waves, it is recommended that the pairwise approach be used in future analyses to optimize the sample size and statistical power when examining the relationship between FSI in the first years of life and health outcome such as dental caries

Discrete strategies to reduce intake of discretionary food choices: a scoping review

On a population level, dietary improvement strategies have had limited success in preventing the surge in overweight and obesity or reducing risk factors for chronic disease. While numerous multi-component studies have examined whole-of-diet strategies, and single component (i.e. discrete) dietary intervention strategies have targeted an increase in core foods (e.g. fruits, vegetables, dairy), there is a paucity of evidence on the effectiveness of dietary intervention strategies targeting a decrease in discretionary choices. The aim of this review was to identify dietary intervention strategies that are potentially relevant to reducing intake of discretionary choices in 2&ndash;65 year olds. A scoping review was carried out to map the literature on key discrete dietary intervention strategies that are potentially applicable to reducing discretionary choices, and to identify the targeted health/nutrition effects (e.g. improve nutrient intake, decrease sugar intake, and reduce body weight) of these strategies. Studies conducted in participants aged 2&ndash;65 years and published in English by July 20, 2015, were located through electronic searches including the Cochrane Library, Medline, Embase, CINAHL, and Scopus. Three thousand two hundred and eighty three studies were identified from the search, of which 44 met the selection criteria. The dietary intervention strategies included reformulation (n&thinsp;=&thinsp;13), substitution (n&thinsp;=&thinsp;5), restriction/elimination (n&thinsp;=&thinsp;9), supplementation (n&thinsp;=&thinsp;13), and nutrition education/messages (n&thinsp;=&thinsp;4). The key findings of the review were: restricting portion size was consistently beneficial for reducing energy intake in the acute setting; reformulating foods from higher fat to lower fat could be useful to reduce saturated fat intake; substituting discretionary choices for high fibre snacks, fruit, or low/no-calorie beverages may be an effective strategy for reducing energy intake; supplementing nutrient dense foods such as nuts and wholegrain cereals supports an improved overall diet quality; and, a combination of permissive and restrictive nutrition messages may effectively modify behavior to reduce discretionary choices intake. Longer-term, well-controlled studies are required to assess the effectiveness of the identified dietary strategies as interventions to reduce discretionary choices intake

Dietary patterns of infants and toddlers are associated with nutrient intakes

Dietary patterns are a useful summary measure of diet. Few studies have examined the nutrient profiles underpinning the dietary patterns of young children. The study aim is to determine whether dietary patterns at 6 and 15 months of age are associated with nutrient intakes at 8 and 18 months, respectively. Participants were children from the Avon Longitudinal Study of Parents and Children who had complete dietary pattern and nutrient intake data (n = 725 at 6–8 months, n = 535 at 15–18 months). The association between tertiles of dietary pattern scores and nutrient intake was examined using a non-parametric test for trend. Scores on the home-made traditional pattern (6–8 months) were positively associated with median energy intake. Each dietary pattern had different associations with energy-adjusted intakes of macro- and micro-nutrients. At both times, the discretionary pattern was positively and the ready-prepared baby foods pattern was negatively associated with sodium intake. At 6–8 months, calcium and iron intakes decreased across scores on the home-made traditional and breastfeeding patterns, but increased across the ready-prepared baby food patterns. These findings highlight that dietary patterns in infants and toddlers vary in their underlying energy and nutrient composition.Lisa G. Smithers, Rebecca K. Golley, Laima Brazionis, Pauline Emmett, Kate Northstone and John W. Lync

Group-based trajectories of maternal intake of sugar-sweetened beverage and offspring oral health from a prospective birth cohort study

OBJECTIVES: To investigate the trajectory of maternal intake of sugar-sweetened beverages (SSB) during the first five years of their child's life and its effect on the child's dental caries at five years-of-age. METHODS: This is an ongoing prospective population-based birth cohort study in Adelaide, Australia. Mothers completed questionnaires on their SSB intake, socioeconomic factors and health behaviors at the birth of their child and at the ages of one, two and five years. Child dental caries measured as decayed, missing, or filled tooth surfaces was collected by oral examination. Maternal SSB intake was used to estimate the trajectory of SSB intake. The trajectories then became the main exposure of the study. Dental caries at age five years were the primary outcomes. Adjusted mean- and prevalence-ratios were estimated for dental caries, controlling for confounders. RESULTS: 879 children had dental examinations at five years-of-age. Group-based trajectory modeling identified three trajectories of maternal SSB intake: 'Stable low' (40.8%), 'Moderate but increasing' (13.6%), and 'High early' trajectory (45.6%). Multivariable regression analysis found children of mothers in the 'High early' and 'Moderate but increasing' groups to have greater experience of dental caries (MR: 1.37 (95%CI 1.01-1.67), and 1.24 (95%CI 0.96-1.60) than those in the 'Stable low' trajectory, respectively. CONCLUSION: Maternal consumption of SSB during pregnancy and in the early postnatal period influenced their offspring's oral health. It is important to create a low-sugar environment from early childhood. The results suggest that health promotion activities need to be delivered to expecting women or soon after childbirth

Randomized controlled trial of a good practice approach to treatment of childhood obesity in Malaysia: Malaysian childhood obesity treatment trial (MASCOT)

Context. Few randomized controlled trials (RCTs) of interventions for the treatment of childhood obesity have taken place outside the Western world. Aim. To test whether a good practice intervention for the treatment of childhood obesity would have a greater impact on weight status and other outcomes than a control condition in Kuala Lumpur, Malaysia. Methods. Assessor-blinded RCT of a treatment intervention in 107 obese 7- to 11-year olds. The intervention was relatively low intensity (8 hours contact over 26 weeks, group based), aiming to change child sedentary behavior, physical activity, and diet using behavior change counselling. Outcomes were measured at baseline and six months after the start of the intervention. Primary outcome was BMI z-score, other outcomes were weight change, health-related quality of life (Peds QL), objectively measured physical activity and sedentary behavior (Actigraph accelerometry over 5 days). Results. The intervention had no significant effect on BMI z score relative to control. Weight gain was reduced significantly in the intervention group compared to the control group (+1.5 kg vs. +3.5 kg, respectively, t-test p &lt; 0.01). Changes in health-related quality of life and objectively measured physical activity and sedentary behavior favored the intervention group. Conclusions. Treatment was associated with reduced rate of weight gain, and improvements in physical activity and quality of life. More substantial benefits may require longer term and more intensive interventions which aim for more substantive lifestyle changes

Designing a physical activity parenting course : parental views on recruitment, content and delivery

Background Many children do not engage in sufficient levels of physical activity (PA) and spend too much time screen-viewing (SV). High levels of SV (e.g. watching TV, playing video games and surfing the internet) and low levels of PA have been associated with adverse health outcomes. Parenting courses may hold promise as an intervention medium to change children’s PA and SV. The current study was formative work conducted to design a new parenting programme to increase children’s PA and reduce their SV. Specifically, we focussed on interest in a course, desired content and delivery style, barriers and facilitators to participation and opinions on control group provision. Methods In-depth telephone interviews were conducted with thirty two parents (29 female) of 6–8 year olds. Data were analysed thematically. An anonymous online survey was also completed by 750 parents of 6–8 year old children and descriptive statistics calculated. Results Interview participants were interested in a parenting course because they wanted general parenting advice and ideas to help their children be physically active. Parents indicated that they would benefit from knowing how to quantify their child’s PA and SV levels. Parents wanted practical ideas of alternatives to SV. Most parents would be unable to attend unless childcare was provided. Schools were perceived to be a trusted source of information about parenting courses and the optimal recruitment location. In terms of delivery style, the majority of parents stated they would prefer a group-based approach that provided opportunities for peer learning and support with professional input. Survey participants reported the timing of classes and the provision of childcare were essential factors that would affect participation. In terms of designing an intervention, the most preferred control group option was the opportunity to attend the same course at a later date. Conclusions Parents are interested in PA/SV parenting courses but the provision of child care is essential for attendance. Recruitment is likely to be facilitated via trusted sources. Parents want practical advice on how to overcome barriers and suggest advice is provided in a mutually supportive group experience with expert input

Tropical montane cloud forest: Environmental drivers of vegetation structure and ecosystem function

Abstract:Tropical montane cloud forests (TMCF) are characterized by short trees, often twisted with multiple stems, with many stems per ground area, a large stem diameter to height ratio, and small, often thick leaves. These forests exhibit high root to shoot ratio, with a moderate leaf area index, low above-ground production, low leaf nutrient concentrations and often with luxuriant epiphytic growth. These traits of TMCF are caused by climatic conditions not geological substrate, and are particularly associated with frequent or persistent fog and low cloud. There are several reasons why fog might result in these features. Firstly, the fog and clouds reduce the amount of light received per unit area of ground and as closed-canopy forests absorb most of the light that reaches them the reduction in the total amount of light reduces growth. Secondly, the rate of photosynthesis per leaf area declines in comparison with that in the lowlands, which leads to less carbon fixation. Nitrogen supply limits growth in several of the few TMCFs where it has been investigated experimentally. High root : shoot biomass and production ratios are common in TMCF, and soils are often wet which may contribute to N limitation. Further study is needed to clarify the causes of several key features of TMCF ecosystems including high tree diameter : height ratio.This is the author accepted manuscript. The final version is available from Cambridge University Press via http://dx.doi.org/10.1017/S026646741500017