Perceived neighborhood environment and park use as mediators of the effect of area socio-economic status on walking behaviors

Background: Access to local parks can affect walking levels. Neighborhood environment and park use may influence relationships between neighborhood socioeconomic status (SES) and walking.

Methods: Self-report data on perceived park features, neighborhood environment, park use, neighborhood walking and sociodemographics
were obtained from a sample of Australian adults, living in high/low SES areas. Surveys were mailed to 250 randomly selected households within 500m of 12 matched parks. Mediating effects of perceived environment attributes and park use on relationships between area-SES and walking were examined.

Results: Mean frequency of local park use was higher for high-SES residents (4.36 vs 3.16 times/wk, P < .01), who also reported higher levels of park safety, maintenance, attractiveness, opportunities for socialization, and neighborhood crime safety, aesthetics, and traffic safety. Safety and opportunity for socialization were independently positively related to monthly frequency of visits to a local park which, in turn, was positively associated with walking for recreation and total walking. Residents of higher SES areas reported an average 22% (95% CI: 5%, 37%) more weekly minutes of recreational walking than their low SES counterparts.

Conclusion: Residents of high-SES areas live in environments that promote park use, which positively contributes to their weekly amounts of overall and recreational walking.

Habitual physical activity and the risk for depressive and anxiety disorders among older men and women

Background: Regular physical activity is generally associated with psychological well-being, although there are relatively few prospective studies in older adults. We investigated habitual physical activity as a risk factor for de novo depressive and anxiety disorders in older men and women from the general population.
Methods: In this nested case-control study, subjects aged 60 years or more were identified from randomly selected cohorts being followed prospectively in the Geelong Osteoporosis Study. Cases were individuals with incident depressive or anxiety disorders, diagnosed using the Structured Clinical Interview for DSM-IV-TR (SCID-I/NP); controls had no history of these disorders.Habitual physical activity,measured using a validated questionnaire, and other exposures were documented at baseline, approximately four years prior to psychiatric interviews. Those with depressive or anxiety disorders that pre-dated baseline were excluded.
Results: Of 547 eligible subjects, 14 developed de novo depressive or anxiety disorders and were classified as cases; 533 controls remained free of disease. Physical activity was protective against the likelihood of depressive and anxiety disorders; OR = 0.55 (95% CI 0.32–0.94), p = 0.03; each standard deviation increase in the transformed physical activity score was associated with an approximate halving in the likelihood of developing depressive or anxiety disorders. Leisure-time physical activity contributed substantially to the overall physical activity score. Age, gender, smoking, alcohol consumption, weight and socioeconomic status did not substantially confound the association.
Conclusion: This study provides evidence consistent with the notion that higher levels of habitual physical activity are protective against the subsequent risk of development of de novo depressive and anxiety disorders.

Gender differences in personal, social and environmental influences on active travel to and from school for Australian adolescents

Active travel (walking or cycling for transport) is an important contributor to adolescents overall physical activity (PA). This study examines associations between personal, social and environmental variables and active travel to and from school using data from a large observational study to examine active travel in 2961 year 6 and 8 students (48.7% male), aged 10–14 years (M = 11.4, SD = 0.8 yrs) from 231 schools. Participants completed an on-line survey and all reported living within 2 km of school. Data collected included mode of travel to and from school, self-reported health, and PA variables. Social environmental variables included having playgrounds, parks or gyms close by, feeling safe to walk alone, barriers to walking in the neighbourhood (e.g. traffic, no footpaths), peer and family support for PA, existence of sports teams/scout groups, community disorder and perceived neighbourhood safety. Results showed that while more girls (44.3%) than boys (37.4%) walked to school, lower proportions rode bikes (8.3% vs 22.4%) and hence fewer were active travellers overall. Logistic regression models, adjusted for age, location and socio-economic status were conducted for active travel to/from school, separately for boys and girls. Predictors for boys and girls being ‘active travellers’ to/from school included recreational facilities close to home, higher perceived safety of the neighbourhood and higher community disorder. For boys, social support from friends, scout groups available and higher enjoyment of physical activity was also important. These findings suggest areas for future research and may be used to guide strategies to increase active travel to and from school.

Relationships of land use mix with walking for transport : do land uses and geographical scale matter?

Physical activity and public health recommendations now emphasize the creation of activity-friendly neighborhoods. Mixed land use in a neighborhood is important in this regard, as it reflects the availability of destinations to which residents can walk or ride bicycles, and thus is likely to contribute to residents’ active lifestyles that in turn will influence their overall health. Relationships between land use mix (LUM) and physical activity have not been apparent in some studies, which may be because geographical scale and the specificity of hypothesized environment–behavior associations are not taken into account. We compared the strength of association of four Geographic Information Systems-derived LUM measures with walking for transport and perceived proximity to destinations. We assessed physical activity behaviors of 2,506 adults in 154 Census Collection Districts (CCDs) in Adelaide, Australia, for which ‘‘original’’ LUM measures were calculated, and then refined by either: accounting for the geographic scale of measurement; including only the most-relevant land uses; or, both. The refined (but not the ‘‘original’’) LUM measures had significant associations with the frequency of walking for transport (p < 0.05) and area-corrected measures had significant associations with the duration of walking for transport. All LUM measures had significant associations with perceived proximity to destinations, but stronger associations were seen when using the refined measures compared with the original LUM. Identifying the LUM attributes most strongly associated with walking for transport is a priority and can inform environmental and policy initiatives that are needed to promote health-enhancing physical activity.

Perceptions of representatives of public, private, and community sector institutions of the barriers and enablers for physically active transport

Active transport bridges many shared concerns in the public health and transport sectors. To positively affect opportunities for active transport, public health and transport professionals are engaging with other sectors, including urban planning, housing, recreation, retail, education, and employer groups. A first step in such inter-sectoral collaboration is to understand the perceptions of key players in all of these sectors. This paper describes the results of structured interviews with senior and middle-level administrators from public, private, and community groups in a rapidly developing region in Queensland, Australia, to assess the perceived barriers and enablers to active transport. Key themes emerged relating to infrastructure delivery, public transport services, walk- and cycle-friendly community attributes, political leadership and government coordination, and societal travel norms and culture. There were also themes relating to limits due to resources and limited relevant technical expertise, institutional and practitioner cultures, and agencies not identifying with their roles in active transport. Policies and cross-government initiatives were seen to hold promise, including economic incentives and built environment guidelines, campaigns targeting public attitudes and opinions, and community participation in policy-making. These elements are potential keys to positively promoting comprehensive active transport initiatives among gatekeepers and leaders across different sectors.

Lower levels of physical activity in childhood associated with adult depression

Emerging evidence indicates that early life exposures influence adult health outcomes and there is cause to hypothesise a role for physical activity (PA) in childhood as a protective factor in adult depression. This study aimed to investigate the association between self-reported levels of PA in childhood and self-reported depressive illness. Lifetime depression and levels of physical activity (low/high) in childhood (<15 yr) were ascertained by self-report in 2152 adults (20–97 yr) participating in an ongoing epidemiological study in south-eastern Australia. Data were collected between 2000 and 2006. In this sample, 141 women (18.9%) and 169 men (12.0%) reported ever having a depressive episode. Low PA in childhood was associated with an increased risk of reporting depression in adulthood (OR = 1.70, 95%CI = 1.32–2.17, p < 0.001). Adjustment for age, gender and adult PA attenuated the relationship somewhat (OR = 1.35, 95%CI = 1.01–1.78, p = 0.04), however further adjustment for SES or country of birth did not affect this relationship. In this community-based study, lower levels of self-reported PA in childhood were associated with a 35% increase in odds for self-reported depression in adulthood. These results are consistent with the hypothesis that lower levels of PA in childhood may be a risk factor for adult depression.

Conservation of archaeological daga (adobe) structures, Domboshaba National Monument, Botswana

Domboshaba is a Zimbabwe culture site in eastern Botswana. It had been suffering from neglect until an Africa 2009 documentation workshop was held there. This workshop recommended remedial conservation to arrest the deterioration of the dry stone walls and daga (abode) structures at the site. This paper presents some of the accomplishments of the workshop and the methods used to preserve the daga structures at Domboshaba. It also offers recommendations for others managing these types of sites in southern Africa.

Historical data of Backwell IXL: a Geelong appliance, car component and foundry products manufacturer

The collection documents the history of the Geelong company, Backwell IXL, which commenced in 1858 (first trading under the name E. Backwell & Son) as a blacksmith's shop and stove maker and covers the growth of the business to an appliance, car component and foundry products manufacturer. This collection comprises records, accounts, photographs and product data sheets. It also includes the manuscript of the 'Memoirs of Albert Leslie Backwell', which contained a brief history of the company from the late 1850s to 1980s, including recollections of the management of the company from the early 1920s to the mid 1975s.

Droughts, floods and freshwater ecosystems : evaluating climate change impacts and developing adaptation strategies

Climate change is expected to have significant impacts on hydrologic regimes and freshwater ecosystems, and yet few basins have adequate numerical models to guide the development of freshwater climate adaptation strategies. Such strategies can build on existing freshwater conservation activities, and incorporate predicted climate change impacts. We illustrate this concept with three case studies. In the Upper Klamath Basin of the western USA, a shift in land management practices would buffer this landscape from a declining snowpack. In the Murray–Darling Basin of south-eastern Australia, identifying the requirements of flood-dependent natural values would better inform the delivery of environmental water in response to reduced runoff and less water. In the Savannah Basin of the south-eastern USA, dam managers are considering technological and engineering upgrades in response to more severe floods and droughts, which would also improve the implementation of recommended environmental flows. Even though the three case studies are in different landscapes, they all contain significant freshwater biodiversity values. These values are threatened by water allocation problems that will be exacerbated by climate change, and yet all provide opportunities for the development of effective climate adaptation strategies.

A prospective study of diet quality and mental health in adolescents

Objectives: A number of cross-sectional and prospective studies have now been published demonstrating inverse relationships between diet quality and the common mental disorders in adults. However, there are no existing prospective studies of this association in adolescents, the onset period of most disorders, limiting inferences regarding possible causal relationships.
Methods: In this study, 3040 Australian adolescents, aged 11–18 years at baseline, were measured in 2005–6 and 2007–8. Information on diet and mental health was collected by self-report and anthropometric data by trained researchers.
Results: There were cross-sectional, dose response relationships identified between measures of both healthy (positive) and unhealthy (inverse) diets and scores on the emotional subscale of the Pediatric Quality of Life Inventory (PedsQL), where higher scores mean better mental health, before and after adjustments for age, gender, socio-economic status, dieting behaviours, body mass index and physical activity. Higher healthy diet scores at baseline also predicted higher PedsQL scores at follow-up, while higher unhealthy diet scores at baseline predicted lower PedsQL scores at follow-up. Improvements in diet quality were mirrored by improvements in mental health over the follow-up period, while deteriorating diet quality was associated with poorer psychological functioning. Finally, results did not support the reverse causality hypothesis.
Conclusion: This study highlights the importance of diet in adolescence and its potential role in modifying mental health over the life course. Given that the majority of common mental health problems first manifest in adolescence, intervention studies are now required to test the effectiveness of preventing the common mental disorders through dietary modification.

Modeling of light propagation through biological tissues : a novel approach

An efficient numerical technique for modeling biological tissues using the radiative transfer equation is presented. Time dependence of the transient radiative transfer equation is approximated using Laguerre expansion. Azimuthal angle is discretized using the discrete ordinates method and the resulting set of ordinary differential equations is solved using the Runge-Kutta-Felhberg method.

Laguerre Runge-Kutta-Fehlberg method for simulating laser pulse propagation in biological tissue

An efficient algorithm for solving the transient radiative transfer equation for laser pulse propagation in biological tissue is presented. A Laguerre expansion is used to represent the time dependency of the incident short pulse. The Runge–Kutta– Fehlberg method is used to solve the intensity. The discrete ordinates method is used to discretize with respect to azimuthal and zenith angles. This method offers the advantages of representing the intensity with a high accuracy using only a few Laguerre polynomials, and straightforward extension to inhomogeneous media. Also, this formulation can be easily extended for solving the 2-D and 3-D transient radiative transfer equations.