On your bike! A cross-sectional study of the individual, social and environmental correlates of cycling to school

Background : Active school transport (AST) has declined rapidly in recent decades. While many studies have examined walking, cycling to school has received very little attention. Correlates of cycling are likely to differ to those from walking and cycling enables AST from further distances. This study examined individual, social and environmental factors associated with cycling to school among elementary school-aged children, stratified by gender.

Methods : Children (n = 1197) attending 25 Australian primary schools located in high or low walkable neighborhoods, completed a one-week travel diary and a parent/child questionnaire on travel habits and attitudes.

Results : Overall, 31.2% of boys and 14.6% of girls cycled ≥ 1 trip/week, however 59.4% of boys and 36.7% of girls reported cycling as their preferred school transport mode. In boys (but not girls), school neighborhood design was significantly associated with cycling: i.e., boys attending schools in neighborhoods with high connectivity and low traffic were 5.58 times more likely to cycle (95% CI 1.11-27.96) and for each kilometer boys lived from school the odds of cycling reduced by 0.70 (95% CI 0.63-0.99). Irrespective of gender, cycling to school was associated with parental confidence in their child's cycling ability (boys: OR 10.39; 95% CI 3.79-28.48; girls: OR 4.03; 95% CI 2.02-8.05), parental perceived convenience of driving (boys: OR 0.42; 95% CI 0.23-0.74; girls: OR 0.40; 95% CI 0.20-0.82); and child's preference to cycle (boys: OR 5.68; 95% CI 3.23-9.98; girls: OR 3.73; 95% CI 2.26-6.17).

Conclusion : School proximity, street network connectivity and traffic exposure in school neighborhoods was associated with boys (but not girls) cycling to school. Irrespective of gender, parents need to be confident in their child's cycling ability and must prioritize cycling over driving.

A cross-sectional study of the individual, social, and built environmental correlates of pedometer based physical activity among elementary school children

Background: Children who participate in regular physical activity obtain health benefits. Preliminary pedometerbased cut-points representing sufficient levels of physical activity among youth have been established; however limited evidence regarding correlates of achieving these cut-points exists. The purpose of this study was to identify correlates of pedometer-based cut-points among elementary school-aged children.
Method: A cross-section of children in grades 5-7 (10-12 years of age) were randomly selected from the most (n = 13) and least (n = 12) ‘walkable’ public elementary schools (Perth, Western Australia), stratified by socioeconomic status. Children (n = 1480; response rate = 56.6%) and parents (n = 1332; response rate = 88.8%) completed a survey, and steps were collected from children using pedometers. Pedometer data were categorized to reflect the sex-specific pedometer-based cut-points of ≥15000 steps/day for boys and ≥12000 steps/day for girls. Associations between socio-demographic characteristics, sedentary and active leisure-time behavior, independent mobility, active transportation and built environmental variables - collected from the child and parent surveys - and meeting pedometer-based cut-points were estimated (odds ratios: OR) using generalized estimating equations.
Results: Overall 927 children participated in all components of the study and provided complete data. On average, children took 11407 ± 3136 steps/day (boys: 12270 ± 3350 vs. girls: 10681 ± 2745 steps/day; p < 0.001) and 25.9% (boys: 19.1 vs. girls: 31.6%; p < 0.001) achieved the pedometer-based cut-points. After adjusting for all other variables and school clustering, meeting the pedometer-based cut-points was negatively associated (p < 0.05) with being male (OR = 0.42), parent self-reported number of different destinations in the neighborhood (OR 0.93), and a friend’s (OR 0.62) or relative’s (OR 0.44, boys only) house being at least a 10-minute walk from home. Achieving the pedometer-based cut-points was positively associated with participating in screen-time < 2 hours/day (OR 1.88), not being driven to school (OR 1.48), attending a school located in a high SES neighborhood (OR 1.33), the average number of steps among children within the respondent’s grade (for each 500 step/day increase: OR 1.29), and living further than a 10-minute walk from a relative’s house (OR 1.69, girls only).
Conclusions: Comprehensive multi-level interventions that reduce screen-time, encourage active travel to/from school and foster a physically active classroom culture might encourage more physical activity among children.

Individual, social, and physical environment factors associated with electronic media use among children : sedentary behavior at home

Background: Individual, home social and physical environment correlates of electronic media (EM) use among children were examined and pattern of differences on school and weekend days.
Methods: Youth (n = 298) aged 11 to 12 years self-reported time spent using EM (TV, video/DVD, computer use, and electronic games) on a typical school and a weekend day, each dichotomized at the median to indicate heavy and light EM users. Anthropometric measurements were taken. Logistic regression examined correlates of EM use.
Results: In total, 87% of participants exceeded electronic media use recommendations of ≤ 2 hrs/day. Watching TV during breakfast (OR = 3.17) and after school (OR = 2.07), watching TV with mother (OR = 1.96), no rule(s) limiting time for computer game usage (OR = 2.30), having multiple (OR = 2.99) EM devices in the bedroom and BMI (OR = 1.15) were associated with higher odds of being heavy EM user on a school day. Boys (OR = 2.35) and participants who usually watched TV at midday (OR = 2.91) and late at night (OR = 2.04) had higher odds of being a heavy EM user on the weekend.
Conclusions: Efforts to modify children’s EM use should focus on a mix of intervention strategies that address patterns and reinforcement of TV viewing, household rules limiting screen time, and the presence of EM devices in the child’s bedroom.

Accounting for the multidimensional nature of the relationship between adult obesity and socio-economic status : the French second National Individual Survey on Food Consumption (INCA 2) dietary survey (2006–07)

The objective was to study the multidimensional nature of the relationship between adult obesity (OB) and socio-economic status (SES),
using comprehensive indices of SES taken separately or synthesised in an overall index. A nationally representative sample of adults aged
18–79 years was taken from the French second National Individual Survey on Food Consumption (INCA 2) dietary survey (2006–07).
Weight and height were measured and OB defined as BMI $ 30 kg/m². SES variables were reported in questionnaires and included
occupation, education and characteristics of household wealth. Composite indices of SES (household wealth and overall SES indices)
were computed by correspondence analysis, and relationships with OB were investigated with logistic regression analysis. In total, 11·8
(95% CI 10·1, 13·4) % of French adults were obese, without significant difference by sex. While no significant relationship was observed
in men, all SES indicators were inversely correlated to OB in women. Both education and the household wealth index were retained in the
stepwise multivariate model, confirming that different socio-economic variables are not necessarily proxies of each other regarding the OB
issue. On the other hand, ‘controlling for SES’ while including several measures of SES in multivariate models may lead to collinearity, and
thus over-adjustment. A more integrative approach may be to derive a synthetic index by including the SES factors available in a given
study. Beyond this methodological perspective, understanding how OB is related to the different dimensions of SES should help to
target the more vulnerable groups and increase the effectiveness of prevention.

Individual, social, and physical environmental correlates of physical activity among young women at risk of depression

Background : A number of factors have been identified as important correlates of physical activity (PA) among young women. Young women at risk of depression have a greater likelihood of being physically inactive and it is unknown whether correlates differ for women at risk and not at risk of depression.

Methods : A sample of 451 women aged 18-35 years self-reported leisure-time PA, enjoyment of and self-efficacy for walking and vigorous PA, barriers, social support, access to sporting/leisure facilities and access to sporting equipment in the home. Depression risk was assessed using the General Health Questionnaire (cut point ≥5). Logistic regression analyses examined differences in PA correlates among women at risk and not at risk of depression.

Results : Self-efficacy for vigorous PA was statistically different between groups in predicting odds for meeting PA recommendations but odds ratios were similar across groups. No other significant interactions between correlates and depressive symptoms were identified.

Conclusions : The findings suggest few differences in the individual, social and physical environmental correlates of PA among young women who are and are not at risk of depression. Further research is needed to confirm the existence of any PA correlates specific to this high-risk target group.

Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans

Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited, even for important zoonotic host-pathogen systems, owing to the intractability of host status prior to infection. Using novel applications of stable isotope ecology and eco-immunology, we distinguish antecedent behavioural and physiological traits associated with avian influenza virus (AIV) infection in free-living Bewick's swans (Cygnus columbianus bewickii). Swans infected with AIV exhibited higher serum δ13C (-25.3 ± 0.4) than their non-infected counterparts (-26.3±0.2). Thus, individuals preferentially foraging in aquatic rather than terrestrial habitats experienced a higher risk of infection, suggesting that the abiotic requirements of AIV give rise to heterogeneity in pathogen exposure. Juveniles were more likely to be infected (30.8% compared with 11.3% for adults), shed approximately 15-fold higher quantity of virus and exhibited a lower specific immune response than adults. Together, these results demonstrate the potential for heterogeneity in infection to have a profound influence on the dynamics of pathogens, with concomitant impacts on host habitat selection and fitness.

Individual differences predict susceptibility to conditioned fear arising from psychosocial trauma

Background : Classical Pavlovian fear conditioning has been widely used in preclinical studies to gain insights into anxiety-related disorders. In this study we examined whether pre-existing behavioral differences, and/or behavioral differences displayed during fear induction, predict the severity of the conditioned fear response that can develop after an episode of psychosocial conflict.

Methods : Prior to conditioning, male rats (intruders) were behaviorally assessed using the novel environment exploration and defensive burying tests. These animals were subsequently placed in the territory of an older male (resident) that invariably attacked the intruder.

Results : Upon return to this territory 24 h later, intruders moved less than controls and produced more distress vocalizations, indicating conditioned fear to context. Additionally, analyses revealed that both pre-existing behavioral differences, and the animal’s response during social conflict, predicted the magnitude of the subsequent conditioned fear response. Specifically, animals that engaged in higher levels of novel environment exploration, that exhibited a greater number of defensive burying behaviors, and that demonstrated higher levels of fighting and guarding during social conflict, displayed less evidence of conditioned fear.

Conclusion : These findings show that the behavioral variability existent within a normal outbred population can predict the magnitude of the conditioned fear response.

A Bayesian framework for learning shared and individual subspaces from multiple data sources

This paper presents a novel Bayesian formulation to exploit shared structures across multiple data sources, constructing foundations for effective mining and retrieval across disparate domains. We jointly analyze diverse data sources using a unifying piece of metadata (textual tags). We propose a method based on Bayesian Probabilistic Matrix Factorization (BPMF) which is able to explicitly model the partial knowledge common to the datasets using shared subspaces and the knowledge specific to each dataset using individual subspaces. For the proposed model, we derive an efficient algorithm for learning the joint factorization based on Gibbs sampling. The effectiveness of the model is demonstrated by social media retrieval tasks across single and multiple media. The proposed solution is applicable to a wider context, providing a formal framework suitable for exploiting individual as well as mutual knowledge present across heterogeneous data sources of many kinds.

Increasing children’s physical activity : individual, social, and environmental factors associated with walking to and from school

Background. Efforts to increase the prevalence of children’s active school transport require evidence to inform the development of comprehensive interventions. This study used a multilevel ecological framework to investigate individual, social, and environmental factors associated with walking to and from school among elementary school-aged children, stratified by gender.
Method. Boys aged 10 to 13 years (n = 617) and girls aged 9 to 13 years (n = 681) attending 25 Australian primary schools located in high or low walkable neighborhoods completed a 1-week travel diary and a parent/child questionnaire on travel habits and attitudes.
Results. Boys were more likely (odds ratio [OR] = 3.37; p < .05) to walk if their school neighborhood had high connectivity and low traffic and less likely to walk if they had to cross a busy road (OR = 0.49; p < .05). For girls, confidence in their ability to walk to or from school without an adult (OR = 2.03), school encouragement (OR = 2.43), scheduling commitments (OR = 0.41), and parent-perceived convenience of driving (OR = 0.24) were significantly associated (p < .05) with walking. Irrespective of gender and proximity to school, child-perceived convenience of walking (boys OR = 2.17 and girls OR = 1.84) and preference to walk to school (child perceived, boys OR = 5.57, girls OR = 1.84 and parent perceived, boys OR = 2.82, girls OR = 1.90) were consistently associated (p < .05) with walking to and from school.
Conclusion. Although there are gender differences in factors influencing children walking to and from school, proximity to school, the safety of the route, and family time constraints are consistent correlates. These need to be addressed if more children are to be encouraged to walk to and from school.

Do the individual, social, and environmental correlates of physical activity differ between urban and rural women?

In this article, associations between individual, social, and environmental factors and physical activity among 3,669 women (18-45 years) living in socioeconomically disadvantaged urban and rural areas were compared. In 2007-2008, participants reported levels of leisure-time physical activity (LTPA) and transport-related physical activity (TRPA) as well as five individual, four social, and three environmental factors. Physical activity self- efficacy demonstrated stronger associations with LTPA among urban relative to rural women; child care was associated with LTPA and intentions with TRPA among urban women only, and enjoyment was associated with TRPA among rural women only. Correlates of physical activity among urban and rural women were generally similar, although some tailoring of physical activity promotion strategies may be warranted.

"The solution needs to be complex." Obese adults' attitudes about the effectiveness of individual and population based interventions for obesity

Background
Previous studies of public perceptions of obesity interventions have been quantitative and based on general population surveys. This study aims to explore the opinions and attitudes of obese individuals towards population and individual interventions for obesity in Australia.

Methods
Qualitative methods using in-depth semi-structured telephone interviews with a community sample of obese adults (Body Mass Index ≥30). Theoretical, purposive and strategic recruitment techniques were used to ensure a broad sample of obese individuals with different types of experiences with their obesity. Participants were asked about their attitudes towards three population based interventions (regulation, media campaigns, and public health initiatives) and three individual interventions (tailored fitness programs, commercial dieting, and gastric banding surgery), and the effectiveness of these interventions.

Results
One hundred and forty two individuals (19-75 years) were interviewed. Participants strongly supported non-commercial interventions that were focused on encouraging individuals to make healthy lifestyle changes (regulation, physical activity programs, and public health initiatives). There was less support for interventions perceived to be invasive or high risk (gastric band surgery), stigmatising (media campaigns), or commercially motivated and promoting weight loss techniques (commercial diets and gastric banding surgery).

Conclusion
Obese adults support non-commercial, non-stigmatising interventions which are designed to improve lifestyles, rather than promote weight loss.

Long-term species, sexual and individual variations in foraging strategies of fur seals revealed by stable isotopes in whiskers

Background: Individual variations in the use of the species niche are an important component of diversity in trophic interactions. A challenge in testing consistency of individual foraging strategy is the repeated collection of information on the same individuals.

Methodology/Principal Findings: The foraging strategies of sympatric fur seals (Arctocephalus gazella and A. tropicalis) were examined using the stable isotope signature of serially sampled whiskers. Most whiskers exhibited synchronous delta C-13 and delta N-15 oscillations that correspond to the seal annual movements over the long term (up to 8 years). delta C-13 and delta N-15 values were spread over large ranges, with differences between species, sexes and individuals. The main segregating mechanism operates at the spatial scale. Most seals favored foraging in subantarctic waters (where the Crozet Islands are located) where they fed on myctophids. However, A. gazella dispersed in the Antarctic Zone and A. tropicalis more in the subtropics. Gender differences in annual time budget shape the seal movements. Males that do not perform any parental care exhibited large isotopic oscillations reflecting broad annual migrations, while isotopic values of females confined to a limited foraging range during lactation exhibited smaller changes. Limited inter-individual isotopic variations occurred in female seals and in male A. tropicalis. In contrast, male A. gazella showed large inter-individual variations, with some males migrating repeatedly to high-Antarctic waters where they fed on krill, thus meaning that individual specialization occurred over years.

Conclusions/Significance: Whisker isotopic signature yields unique long-term information on individual behaviour that integrates the spatial, trophic and temporal dimensions of the ecological niche. The method allows depicting the entire realized niche of the species, including some of its less well-known components such as age-, sex-, individual- and migration-related changes. It highlights intrapopulation heterogeneity in foraging strategies that could have important implications for likely demographic responses to environmental variability.