Effect of Australia's walk to work day campaign on adults' active commuting and physical activity behavior

Purpose. To determine whether Australia's Walk to Work Day media campaign resulted in behavioural change among targeted groups. Methods. Pre- and postcampaign telephone surveys of a cohort of adults aged 18 to 65 years (n = 1100, 55% response rate) were randomly sampled from Australian major melropolitan areas. Tests for dependent samples were applied (McNemax chi(2) or paired t-test). Results. Among participants who did not usually actively commute to work was a significant decrease in car only use an increase in walking combined with public transport. Among those who were employed was a significant increase in total time walking (+16 min/wk; t [780] = 2.04, p < .05) and in other moderate physical activity (+120 min/wk; t [1087] = 4.76, p < .005), resulting in a significant decrease in the proportion who were inactive (chi(2) (1) = 6.1, p < .05). Conclusion. Although nonexperimental, the Walk to Work Day initiative elicited short-term changes in targeted behaviors among target groups. Reinforcement by integrating worksite health promotion strategies may be required for sustained effects.

Neighborhood environmental factors correlated with walking near home: Using SPACES

Purpose: The physical environment plays an important role in influencing participation in physical activity, although the specific factors that are correlated with different patterns of walking remain to be determined We examined correlations between physical environmental factors and self-reported walking for recreation and transport near home. Methods: The local neighborhood environments (defined as a 400-m radius from the respondent's home) of 1678 adults were assessed for their suitability for walking. The environmental data were collected during 2000 using the Systematic Pedestrian and Cycling Environmental Scan (SPACES) instrument together with information from other sources. We used logistic regression modeling to examine the relationship between the attributes of the physical environment and the self-reported walking behavior undertaken near home. Results: Functional features were correlated with both walking for recreation (odds ratio (OR) 1.62; 95% confidence interval (Cl): 1.20-2.19) and for transport (OR 1.30; 95% Cl: 0.97-1.73). A well-maintained walking surface was the main functional factor associated with walking for recreation (OR 2.04; 95% Cl: 1.43-2.91) and for transport (OR 2.13; 95% Cl: 1.53-2.96). Destination factors, such as shops and public transport, were significantly correlated with walking for transport (OR 1.80; 95% Cl: 1.33-2.44), but not recreation. Conclusion: The findings suggest that neighborhoods with pedestrian facilities that are attractive and comfortable and where there are local destinations (such as shops and public transport) are associated with walking near home.

A Review of the Environmental and Health Effects of Termiticides under Australian Conditions

There exists a major cost issue as regards termite damage to wooden structures. A factor in this cost has been the increasing trend towards slab-on-ground construction. Current literature has been reviewed in relation to concerns about the possible public/environmental health consequences of the repeated use of termiticides in large quantities. The previous, current and projected future use patterns of termiticides are reviewed in the context of techniques appropriate for termite control and treatment priorities. The phasing out of organochlorine termiticides in Australia was undertaken to minimise impact of these substances on the environment and to a lesser extent on public health. These persistent chemicals were replaced by substances with high activity but relatively low persistence in the soil. There has also been an increase in the use of alternative methods (e.g. physical barriers) for the control of termites. The transition away from organochlorine termiticides has led to a realisation that significant information gaps exist with regard to replacement chemicals and other technologies. Although relatively persistent, the organochlorine chemicals have a limited lifespan in soils. Their concentrations are gradually attenuated by processes such as transport away from the point of application and biodegradation. Wooden structures originally treated with these substances will, with the passing of time, be at risk of termite infestation. The only available option is re-treatment with chemicals currently registered for termite control. Thus, there are likely to be substantial future increases associated with the cost of re-treatment and repairs of older slab-on-ground dwellings. More information is required on Australian termite biology, taxonomy and ecology. The risks of termite infestation need to be evaluated, both locally and nationally so that susceptible or high risk areas, structures and building types can be identified and preventive measures taken in terms of design and construction. Building regulations and designs need to be able to reduce or eliminate high-risk housing; and eliminate or reduce conditions that are attractive to termites and/or facilitate termite infestation.

The changing public-private infrastructure mix: Economy-wide implications

This article provides an economy-wide perspective on the changing role of the public sector in developing economic and social infrastructure in Australia. It analyses the scale and macroeconomic significance of the key economic and social infrastructure sectors - communication services, electricity, gas and water supply, transport, education, health and community services, government administration and defence. It then canvasses the major policy issues that have arisen in the progression from public to private infrastructure provision and considers why concerns about the trend fall in traditional public works spending may be misplaced in light of recent economic and institutional changes.

Development of lipid-core-peptide (LCP) based vaccines for the prevention of the group A streptococcal (GAS) infection

Traditional vaccines consisting of whole attenuated micro-organisms. or microbial components administered with adjuvant, have been demonstrated as one of the most cost-effective and successful public health interventions. Their use in large scale immunisation programs has lead to the eradication of smallpox, reduced morbidity and mortality from many once common diseases, and reduced strain on health services. However, problems associated with these vaccines including risk of infection. adverse effects, and the requirement for refrigerated transport and storage have led to the investigation of alternative vaccine technologies. Peptide vaccines, consisting of either whole proteins or individual peptide epitopes, have attracted much interest, as they may be synthesised to high purity and induce highly specific immune responses. However, problems including difficulties stimulating long lasting immunity. and population MHC diversity necessitating multiepitopic vaccines and/or HLA tissue typing of patients complicate their development. Furthermore, toxic adjuvants are necessary to render them immunogenic. and as such non-toxic human-compatible adjuvants need to be developed. Lipidation has been demonstrated as a human compatible adjuvant for peptide vaccines. The lipid-core-peptide (LCP) system. incorporating lipid adjuvant, carrier, and peptide epitopes, exhibits promise as a lipid-based peptide vaccine adjuvant. The studies reviewed herein investigate the use of the LCP system for developing vaccines to protect against group A streptococcal (GAS) infection. The studies demonstrate that LCP-based GAS vaccines are capable of inducing high-titres of antigen specific IgG antibodies. Furthermore. mice immunised with an LCP-based GAS vaccine were protected against challenge with 8830 strain GAS.

Adsorbate transport in nanopores

We present a tractable theory of transport of simple fluids in cylindrical nanopores, considering trajectories of molecules between diffuse wall collisions at low-density, and including viscous flow contributions at higher densities. The model is validated through molecular dynamics simulations of supercritical methane transport, over a wide range of conditions. We find excellent agreement between model and simulation at low to medium densities. However, at high densities the model tends to over-predict the transport behaviour, due to a large decrease in surface slip that is not well represented by the model. It is also seen that the concept of activated diffusion, commonly associated with diffusion in small pores, is fundamentally invalid for smooth pores.

Comparisons of diffusive and viscous contributions to transport coefficients of light gases in single-walled carbon nanotubes

We examine here the relative importance of different contributions to transport of light gases in single walled carbon nanotubes, using methane and hydrogen as examples. Transport coefficients at 298 K are determined using molecular dynamics simulation with atomistic models of the nanotube wall, from which the diffusive and viscous contributions are resolved using a recent approach that provides an explicit expression for the latter. We also exploit an exact theory for the transport of Lennard-Jones fluids at low density considering diffuse reflection at the tube wall, thereby permitting the estimation of Maxwell coefficients for the wall reflection. It is found that reflection from the carbon nanotube wall is nearly specular, as a result of which slip flow dominates, and the viscous contribution is small in comparison, even for a tube as large as 8.1 nm in diameter. The reflection coefficient for hydrogen is 3-6 times as large as that for methane in tubes of 1.36 nm diameter, indicating less specular reflection for hydrogen and greater sensitivity to atomic detail of the surface. This reconciles results showing that transport coefficients for hydrogen and methane, obtained in simulation, are comparable in tubes of this size. With increase in adsorbate density, the reflection coefficient increases, suggesting that adsorbate interactions near the wall serve to roughen the local potential energy landscape perceived by fluid molecules.

Effects of the juxtaposition of carbonaceous slit pores on the overall transport behavior of adsorbed fluids

It is a common approximation in the modeling of adsorption in microporous carbons to treat the pores as slit pores, whose walls are considered to consist of an infinite number of graphitic layers. In practice, such an approximation is appropriate as long as the number of graphitic layers in the wall is greater than three. However, it is understood that pore walls in microporous carbons commonly consist of three or fewer layers. As well as affecting the solid-fluid interaction within a pore, such narrow walls permit the interaction of fluid molecules through the wall, with consequences for the adsorption characteristics. We consider the effect that a distributed pore-wall thickness model can have on transport properties. At low density we find that the only significant deviation in the transport properties from the infinite pore-wall thickness model occurs in pores with single-layer walls. For a model of activated carbons with a distribution of pore widths and pore-wall thicknesses, the transport properties are generally insensitive to the effects of finite walls, in terms of both the solid-fluid interaction within a pore and fluid-fluid interaction through the pore walls.

Heterogeneous model for gas transport in carbon molecular sieves

A dual resistance model with distribution of either barrier or pore diffusional activation energy is proposed in this work for gas transport in carbon molecular sieve (CMS) micropores. This is a novel approach in which the equilibrium is homogeneous, but the kinetics is heterogeneous. The model seems to provide a possible explanation for the concentration dependence of the thermodynamically corrected barrier and pore diffusion coefficients observed in previous studies from this laboratory on gas diffusion in CMS.(1.2) The energy distribution is assumed to follow the gamma distribution function. It is shown that the energy distribution model can fully capture the behavior described by the empirical model established in earlier studies to account for the concentration dependence of thermodynamically corrected barrier and pore diffusion coefficients. A methodology is proposed for extracting energy distribution parameters, and it is further shown that the extracted energy distribution parameters can effectively predict integral uptake and column breakthrough profiles over a wide range of operating pressures.

E-cadherin transport from the trans-Golgi network in tubulovesicular carriers is selectively regulated by Golgin-97

E-cadherin is a cell-cell adhesion protein that is trafficked and delivered to the basolateral cell surface. Membrane-bound carriers for the post-Golgi exocytosis of E-cadherin have not been characterized. Green fluorescent protein (GFP)-tagged E-cadherin (Ecad-GFP) is transported from the trans-Golgi network (TGN) to the recycling endosome on its way to the cell surface in tubulovesicular carriers that resemble TGN tubules labeled by members of the golgin family of tethering proteins. Here, we examine the association of golgins with tubular carriers containing E-cadherin as cargo. Fluorescent GRIP domains from golgin proteins replicate the membrane binding of the full-length proteins and were coexpressed with Ecad-GFP. The GRIP domains of p230/golgin-245 and golgin-97 had overlapping but nonidentical distributions on the TGN; both domains were on TGN-derived tubules but only the golgin-97 GRIP domain coincided with Ecad-GFP tubules in live cells. When the Arl1-binding endogenous golgins, p230/golgin-245 and golgin-97 were displaced from Golgi membranes by overexpression of the p230 GRIP domain, trafficking of Ecad-GFP was inhibited. siRNA knockdown of golgin-97 also inhibited trafficking of Ecad-GFP. Thus, the GRIP domains of p230/golgin-245 and golgin-97 bind discriminately to distinct membrane subdomains of the TGN. Golgin-97 is identified as a selective and essential component of the tubulovesicular carriers transporting E-cadherin out of the TGN.

Rab11 in recycling endosomes regulates the sorting and basolateral transport of E-cadherin

E-cadherin plays an essential role in cell polarity and cell-cell adhesion; however, the pathway for delivery of E-cadherin to the basolateral membrane of epithelial cells has not been fully characterized. We first traced the post-Golgi, exocytic transport of GFP-tagged E-cadherin (Ecad-GFP) in unpolarized cells. In live cells, Ecad-GFP was found to exit the Golgi complex in pleiomorphic tubulovesicular carriers, which, instead of moving directly to the cell surface, most frequently fused with an intermediate compartment, subsequently identified as a Rab11-positive recycling endosome. In MDCK cells, basolateral targeting of E-cadherin relies on a dileucine motif. Both E-cadherin and a targeting mutant, Delta S1-E-cadherin, colocalized with Rab11 and fused with the recycling endosome before diverging to basolateral or apical membranes, respectively. In polarized and unpolarized cells, coexpression of Rab11 mutants disrupted the cell surface delivery of E-cadherin and caused its mistargeting to the apical membrane, whereas apical Delta S1-E-cadherin was unaffected. We thus demonstrate a novel pathway for Rab11 dependent, dileucine-mediated, mu 1B-independent sorting and basolateral trafficking, exemplified by E-cadherin. The recycling endosome is identified as an intermediate compartment for the post-Golgi trafficking and exocytosis of E-cadherin, with a potentially important role in establishing and maintaining cadherin-based adhesion.

Endosome-to-cytosol transport of viral nucleocapsids

During viral infection, fusion of the viral envelope with endosomal membranes and nucleocapsid release were thought to be concomitant events. We show here that for the vesicular stomatitis virus they occur sequentially, at two successive steps of the endocytic pathway. Fusion already occurs in transport intermediates between early and late endosomes, presumably releasing the nucleocapsid within the lumen of intra- endosomal vesicles, where it remains hidden. Transport to late endosomes is then required for the nucleocapsid to be delivered to the cytoplasm. This last step, which initiates infection, depends on the late endosomal lipid lysobisphosphatidic acid ( LBPA) and its putative effector Alix/ AIP1, and is regulated by phosphatidylinositol- 3-phosphate ( PtdIns( 3) P) signalling via the PtdIns( 3) P- binding protein Snx16. We conclude that the nucleocapsid is exported into the cytoplasm after the back- fusion of internal vesicles with the limiting membrane of late endosomes, and that this process is controlled by the phospholipids LBPA and PtdIns( 3) P and their effectors.

Socio-demographic variations in walking for transport and for recreation or exercise among adult Australians

Background: Walking is integral to strategies to promote physical activity. We identified socio-demographic variations in walking for transport, and for recreation or exercise. Methods: Representative population data (n = 3392) from Australia were collected using computer assisted telephone interviewing, to examine adults’ participation in moderate- or brisk-paced walking for transport and walking for recreation or exercise; walking “sufficient” to meet the current public health guideline (> 150 min/wk); and, the contributions of total walking to meeting the guideline for total physical activity. Results: Rates of sufficient walking for transport (10% for men, 9% for women) were lower than those for walking for recreation or exercise (14% for both genders). Few socio-demographic differences emerged. Men over age 60 y were significantly less likely (OR = 0.40) to walk for transport; men age 45 to 59 y were more likely (OR = 1.56) to walk for recreation or exercise. Walking contributed more toward meeting the current public health guideline among women (15% to 21%) than among men (6% to 8%). Conclusions: There is potential for socially equitable increases in participation, through a focus on both walking for transport and on walking for recreation or exercise; attention to gender differences would be helpful.

What does the community think about lifespan extension technologies? The need for an empirical base for ethical and policy debates

Objectives: This paper examines public understandings of possibilities for increasing life expectancy, interest in taking up lifespan-extending interventions, and motivations influencing these intentions. Methods: Structured interviews were conducted with 31 adults, aged 50 and over. Results: Participants believed that technological advances would increase life expectancy but questioned the value of quantity over quality of life. Life in itself was not considered valuable without the ability to put it to good use. Participants would not use technologies to extend their own lifespan unless the result would also enhance their health. Conclusions: These findings may not be generalisable to the general public but they provide the first empirical evidence on the plausibility of common assumptions about public interest in 'anti-ageing' interventions. Surveys of the views of representative samples of the population are needed to inform the development of a research agenda on the ethical, legal and social implications of lifespan extension.