Mass transfer properties (permeability and mass diffusivity) of four australian hardwood species

Characterization of mass transfer properties was achieved in the longitudinal, radial, and tangential directions for four Australian hardwood species: spotted gum, blackbutt, jarrah, and messmate. Measurement of mass transfer properties for these species was necessary to complement current vacuum drying modeling research. Water-vapour diffusivity was determined in steady state using a specific vapometer. Permeability was determined using a specialized device developed to measure over a wide range of permeability values. Permeability values of some species and material directions were extremely low and undetectable by the mass flow meter device. Hence, a custom system based on volume evolution was conceived to determine very low, previously unpublished, wood permeability values. Mass diffusivity and permeability were lowest for spotted gum and highest for messmate. Except for messmate in the radial direction, the four species measured were less permeable in all directions than the lowest published figures, demonstrating the high impermeability of Australian hardwoods and partly accounting for their relatively slow drying rates. Permeability, water-vapour diffusivity, and associated anisotropic ratio data obtained for messmate were extreme or did not follow typical trends and is consequently the most difficult of the four woods to dry in terms of collapse and checking degradation. © The State of Queensland, Department of Agriculture, Fisheries and Forestry, 2012.

The health and cost implications of high body mass index in Australian Defence Force personnel.

BACKGROUND: Frequent illness and injury among workers with high body mass index (BMI) can raise the costs of employee healthcare and reduce workforce maintenance and productivity. These issues are particularly important in vocational settings such as the military, which require good physical health, regular attendance and teamwork to operate efficiently. The purpose of this study was to compare the incidence of injury and illness, absenteeism, productivity, healthcare usage and administrative outcomes among Australian Defence Force personnel with varying BMI. METHODS: Personnel were grouped into cohorts according to the following ranges for (BMI): normal (18.5-24.9 kg/m²; n = 197), overweight (25-29.9 kg/m²; n = 154) and obese (≥30 kg/m²) with restricted body fat (≤28 % for females, ≤24 % for males) (n = 148) and with no restriction on body fat (n = 180). Medical records for each individual were audited retrospectively to record the incidence of injury and illness, absenteeism, productivity, healthcare usage (i.e., consultation with medical specialists, hospital stays, medical investigations, prescriptions) and administrative outcomes (e.g., discharge from service) over one year. These data were then grouped and compared between the cohorts. RESULTS: The prevalence of injury and illness, cost of medical specialist consultations and cost of medical scans were all higher (p <0.05) in both obese cohorts compared with the normal cohort. The estimated productivity losses from restricted work days were also higher (p <0.05) in the obese cohort with no restriction on body fat compared with the normal cohort. Within the obese cohort, the prevalence of injury and illness, healthcare usage and productivity were not significantly greater in the obese cohort with no restriction on body fat compared with the cohort with restricted body fat. The number of restricted work days, the rate of re-classification of Medical Employment Classification and the rate of discharge from service were similar between all four cohorts. CONCLUSIONS: High BMI in the military increases healthcare usage, but does not disrupt workforce maintenance. The greater prevalence of injury and illness, greater healthcare usage and lower productivity in obese Australian Defence Force personnel is not related to higher levels of body fat.

Associations between infant temperament and early feeding practices. A cross-sectional study of Australian mother-infant dyads from the NOURISH randomised controlled trial

The purpose of this study was to investigate the association between temperament in Australian infants aged 2–7 months and feeding practices of their first-time mothers (n=698). Associations between feeding practices and beliefs (Infant Feeding Questionnaire) and infant temperament (easy-difficult continuous scale from the Short Temperament Scale for Infants) were tested using linear and binary logistic regression models adjusted for a comprehensive range of covariates. Mothers of infants with a more difficult temperament reported a lower awareness of infant cues, were more likely to use food to calm and reported high concern about overweight and underweight. The covariate maternal depression score largely mirrored these associations. Infant temperament may be an important variable to consider in future research on the prevention of childhood obesity. In practice, mothers of temperamentally difficult infants may need targeted feeding advice to minimise the adoption of undesirable feeding practices.

Examination of socio-demographics and job satisfaction in Australian registered nurses

Aims and Objectives To examine relationships between socio-demographic factors and job satisfaction and to identify if these factors predict job satisfaction levels in an Australian registered nurses. Background Reports indicate that in Australia there are 30,000 qualified nurses no longer working in the healthcare and that current nursing shortages vary as a result of certain socio-demographic variables including type of nurse, geographic, location, sector, service and organisation. Furthermore it has been revealed that there is not only a real shortage but also a pseudo-shortage (i.e. either there are not enough nurses are available, or not enough are willing to work under existing workplace conditions). International studies have found significant relationships exist between some socio-demographic factors and job satisfaction in registered nurses however there is limited information available on relationships between socio-demographic factors and job satisfaction in nurses in the Australian context. Design A cross sectional survey was undertaken of Australian registered nurses. Methods Two thousand Australian registered nurses who were members of an industrial and professional organisation were sent the questionnaire in 2008. They were stratified and randomised according to gender. Six hundred and thirty-nine registered nurses responded. Descriptive analyses, correlation analyses, one- way ANOVA tests, simple linear regression and multivariable analyses were conducted to examine further if any relationships existed between the variables. Results The majority of respondents showed positive job satisfaction scores. An ANOVA found significant positive relationships existed between job satisfaction, specialty area, health sector and Australian states. Multivariable analyses found relationships existed between specialty area, health sector, and job satisfaction. Conclusions The variables specialty area and health sector were found to be significantly associated with job satisfaction. The different specialty areas and health sectors in relation to job satisfaction should be investigated further. Clinical Relevance The study results have provided new knowledge for policy makers, organisational and nursing leaders of the socio-demographic variables that may affect job satisfaction in registered nurses in the Australian context.

Exeter short stems compared with standard length Exeter stems : experience from the Australian Orthopaedic Association National Joint Replacement Registry

The standard Exeter stem has a length of 150mm with offsets 37.5mm to 56mm. Shorter stems of lengths 95mm, 115mm and 125mm with offsets 35.5mm or less are available for patients with smaller femurs. Concern has been raised regarding the behaviour of the smaller implants. This paper analysed data from the Australian Orthopaedic Association National Joint Replacement Registry comparing survivorship of stems of offset 35.5mm or less with the standard stems of 37.5mm offset or greater. At seven years there was no significant difference in the Cumulative Percent Revision Rate in the short stems (3.4%, 95% CI 2.4-4.8%) compared with the standard length stems (3.5%, 95% CI 3.3-3.8%) despite its use in a greater proportion of potentially more difficult developmental dysplasia of the hip cases.

CO2 emissions from the combustion of native Australian trees

Carbon dioxide (CO2), as a primary product of combustion, is a known factor affecting climate change and global warming. In Australia, CO2 emissions from biomass burning are a significant contributor to total carbon in the atmosphere and therefore, it is important to quantify the CO2 emission factors from biomass burning in order to estimate their magnitude and impact on the Australian atmosphere. This paper presents the quantification of CO2 emission factors for five common tree species found in South East Queensland forests, as well as several grasses taken from savannah lands in the Northern Territory of Australia, under controlled ‘fast burning’ and ‘slow burning’ laboratory conditions. The results showed that CO2 emission factors varied according to the type of vegetation and burning conditions, with emission factors for fast burning being 2574 ± 254 g/kg for wood, 394 ± 40 g/kg for branches and leaves, and 2181 ± 120 g/kg for grass. Under slow burning conditions, the CO2 emission factors were 218 ± 20 g/kg for wood, 392± 80 g/kg for branches and leaves, and 2027 ± 809 g/kg for grass.

Australian lungfish (Neoceratodus forsteri: Dipnoi) have low genetic variation at allozyme and mitochondrial DNA loci : a conservation alert?

Genetic variation at allozyme and mitochondrial DNA loci was investigated in the Australian lungfish, Neoceratodus forsteri Krefft 1870. Tissue samples for genetic analysis were taken non-lethally from 278 individuals representing two spatially distinct endemic populations (Mary and Burnett rivers), as well as one population thought to be derived from an anthropogenic translocation in the 1890's (Brisbane river). Two of 24 allozyme loci resolved from muscle tissue were polymorphic. Mitochondrial DNA nucleotide sequence diversity estimated across 2,235 base pairs in each of 40 individuals ranged between 0.000423 and 0.001470 per river. Low genetic variation at allozyme and mitochondrial loci could be attributed to population bottlenecks, possibly induced by Pleistocene aridity. Limited genetic differentiation was detected among rivers using nuclear and mitochondrial markers suggesting that admixture may have occurred between the endemic Mary and Burnett populations during periods of low sea level when the drainages may have converged before reaching the ocean. Genetic data was consistent with the explanation that lungfish were introduced to the Brisbane river from the Mary river. Further research using more variable genetic loci is needed before the conservation status of populations can be determined, particularly as anthropogenic demands on lungfish habitat are increasing. In the interim we recommend a management strategy aimed at conserving existing genetic variation within and between rivers.

Carrying capacity dashboard analyses : Australian case studies of populations scaled to place

In a globalised world, it makes sense to examine our demands on the landscape through the wide-angle lens of ecological footprint analysis. However, the important impetus towards a more localised societal system suggests a review of this approach and a return to its origins in carrying capacity assessment. The determination of whether we live within or beyond our carrying capacity is entirely scalar, with national, regional and local assessments dependent not only on the choices of the population but the capability of a landscape - at scale. The Carrying Capacity Dashboard, an openly accessible online modelling interface, has been developed for Australian conditions, facilitating analysis at various scales. Like ecological footprint analysis it allows users to test a variety of societal behaviours such as diet, consumption patterns, farming systems and ecological protection practices; but unlike the footprint approach, the results are uniquely tailored to place. This paper examines population estimates generated by the Carrying Capacity Dashboard. It compares results in various scales of analysis, from national to local. It examines the key behavioural choices influencing Australian carrying capacity estimates. For instance, the assumption that the consumption of red meat automatically lowers carrying capacity is examined and in some cases, debunked. Lastly, it examines the implications of implementing carrying capacity assessment globally, but not through a wide angle lens; rather, by examining the landscape one locality at a time.