205 research outputs found

    ESTIMATING RETURNS FROM PAST INVESTMENTS INTO BEEF CATTLE GENETICS RD&E IN AUSTRALIA

    Get PDF
    This study aimed at estimating the costs and benefits of all beef cattle genetic improvement activity, across Australia, over the period 1970 to the present. The total cumulative Present Value (PV) of investments by industry, government and other agencies into selection, crossbreeding and grading up since 1963, and of imported genetics, was estimated to be 340m(in340m (in 2001 at a 7% discount rate). Using a suite of genetic evaluation models, farming systems models and an industry-level model, the cumulative PV of industry returns were estimated. Within-breed selection generated 944m;crossbreedinginsouthernAustralia944m; crossbreeding in southern Australia 255m; changing breed composition in southern Australia 62m;andchangingbreedcompositioninnorthernAustralia62m; and changing breed composition in northern Australia 8.1bn. The benefit/cost ratio for this investment was 28:1 over the last 30 years.Livestock Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    L1 libration point manned space habitat

    Get PDF
    Second generation stations or Manned Space Habitats (MSHs) are discussed for an Earth-Moon libration point and in lunar orbit. The conceptual design of such a station is outlined. Systems and subsystems described reflect anticipation of moderate technology growth. The evolution of the L1 environments is discussed, several selected subsystems are outlined, and how the L1 MSH will complete some of its activities is described

    Developing tools for assessing the fluid structure interaction of passive adaptive composite foils

    No full text
    The study presents an experimental and numerical evaluation of bend-twist elastic coupling in composite passive-adaptive structures. Due to the lack of experimental validation in Fluid Structure Inter-action (FSI) investigations, a full-field deformation of an aerofoil-shaped section under wind loading is measured. The experimental analysis is carried out at the University of Southampton 3.5 m x 2.4 m R. J. Mitchell wind tunnel and involves the use of full-field non-contact measurement techniques such as high speed three dimensional Digital Image Correlation (DIC) and stereoscopic Particle Image Velocimetry (PIV).After assessing the validity and repeatability of the experiments, the study focuses on the development of a numerical FSI investigation that involves the use of a structural and a fluid solver to simulate the aero-elastic behaviour of composite tailored structures with different lay-up arrangements. The numerical analysis is developed as a design tool to allow the structure investigated to maximise bend-twist coupling under increased aerodynamic loading

    Sex Moderates the Relationship That Number of Professional Fights Has With Cognition and Brain Volumes.

    Get PDF
    Objective: Incidence of concussions and report of symptoms are greater among women across sports. While structural brain changes and cognitive declines are associated with repetitive head impact (RHI), the role of sex is not well-understood. This study aimed to determine if there is a moderating effect of sex on the relationship the number of professional fights has with cognitive functioning and regional brain volumes in a cohort of boxers, mixed martial artists, and martial artists. Methods: A total of 55 women were matched with 55 men based on age, years of education, ethnicity, and fighting style. Cognition was assessed via the CNS Vital Signs computerized cognitive battery and supplemental measures. Structural brain scans, demographic data, and number of professional fights (NoPF) were also considered. The matched pairs were compared via analysis of covariance, accounting for total brain volume. Within-subject moderation models were utilized to assess the moderating effect of sex on the relationship between NoPF and brain volumes and cognitive performance. Results: Men were observed to have poorer performance on measures of psychomotor speed when compared to women. On a series of analyses assessing the role of sex as a moderator of the relationship between NoPF and regional brain volumes/cognitive performance, a significant moderation effect was observed across multiple measures of cognitive functioning, such that men had poorer performance. Differences in numerous regional brain volumes were also observed, such that the relationship between NoPF and brain volumes was steeper among men. Conclusion: Sex was observed to be an important moderator in the relationship between NoPF, aspects of cognitive functioning, and volumes of numerous brain regions, suggesting that sex differences in neuroanatomic and cognitive response to RHI deserve further attention

    Role of Mediators in Reducing Antepartum Depressive Symptoms in Rural Low-Income Women Receiving a Culturally Tailored Cognitive Behavioral Intervention

    Get PDF
    Although cognitive behavioral interventions (CBIs) have demonstrated effectiveness for reducing depressive symptoms in the general population, the mechanism for reducing antepartum depressive symptoms (APDS) in rural low-income and minority women is unknown. This study tested the hypothesis that reducing stress and negative thinking, enhancing self-esteem, and increasing social-support will mediate the effect of a CBI on reducing APDS in rural low-income and minority women. Our findings show that CBI may work through reducing stress and negative thinking and enhancing self-esteem, but not social support. The findings also suggest that mental health care providers should emphasize these activities to reduce antepartum depressive symptoms

    Permethrin-Treated Clothing as Protection against the Dengue Vector, Aedes aegypti: Extent and Duration of Protection.

    Get PDF
    INTRODUCTION: Dengue transmission by the mosquito vector, Aedes aegypti, occurs indoors and outdoors during the day. Personal protection of individuals, particularly when outside, is challenging. Here we assess the efficacy and durability of different types of insecticide-treated clothing on laboratory-reared Ae. aegypti. METHODS: Standardised World Health Organisation Pesticide Evaluation Scheme (WHOPES) cone tests and arm-in-cage assays were used to assess knockdown (KD) and mortality of Ae. aegypti tested against factory-treated fabric, home-dipped fabric and microencapsulated fabric. Based on the testing of these three different treatment types, the most protective was selected for further analysis using arm-in cage assays with the effect of washing, ultra-violet light, and ironing investigated using high pressure liquid chromatography. RESULTS: Efficacy varied between the microencapsulated and factory dipped fabrics in cone testing. Factory-dipped clothing showed the greatest effect on KD (3 min 38.1%; 1 hour 96.5%) and mortality (97.1%) with no significant difference between this and the factory dipped school uniforms. Factory-dipped clothing was therefore selected for further testing. Factory dipped clothing provided 59% (95% CI = 49.2%- 66.9%) reduction in landing and a 100% reduction in biting in arm-in-cage tests. Washing duration and technique had a significant effect, with insecticidal longevity shown to be greater with machine washing (LW50 = 33.4) compared to simulated hand washing (LW50 = 17.6). Ironing significantly reduced permethrin content after 1 week of simulated use, with a 96.7% decrease after 3 months although UV exposure did not reduce permethrin content within clothing significantly after 3 months simulated use. CONCLUSION: Permethrin-treated clothing may be a promising intervention in reducing dengue transmission. However, our findings also suggest that clothing may provide only short-term protection due to the effect of washing and ironing, highlighting the need for improved fabric treatment techniques

    Personal Protection of Permethrin-Treated Clothing against Aedes aegypti, the Vector of Dengue and Zika Virus, in the Laboratory.

    Get PDF
    BACKGROUND: The dengue and Zika viruses are primarily transmitted by Aedes aegypti mosquitoes, which are most active during day light hours and feed both in and outside of the household. Personal protection technologies such as insecticide-treated clothing could provide individual protection. Here we assessed the efficacy of permethrin-treated clothing on personal protection in the laboratory. METHODS: The effect of washing on treated clothing, skin coverage and protection against resistant and susceptible Ae. aegypti was assessed using modified WHO arm-in-cage assays. Coverage was further assessed using free-flight room tests to investigate the protective efficacy of unwashed factory-dipped permethrin-treated clothing. Clothing was worn as full coverage (long sleeves and trousers) and partial coverage (short sleeves and shorts). Residual permethrin on the skin and its effect on mosquitoes was measured using modified WHO cone assays and quantified using high-pressure liquid chromatography (HPLC) analysis. RESULTS: In the arm-in-cage assays, unwashed clothing reduced landing by 58.9% (95% CI 49.2-66.9) and biting by 28.5% (95% CI 22.5-34.0), but reduced to 18.5% (95% CI 14.7-22.3) and 11.1% (95% CI 8.5-13.8) respectively after 10 washes. Landing and biting for resistant and susceptible strains was not significantly different (p80% one hour after wearing treated clothing. CONCLUSION: Whilst partially covering the body with permethrin-treated clothing provided some protection against biting, wearing treated clothing with long sleeves and trousers provided the highest form of protection. Washing treated clothing dramatically reduced protection provided. Permethrin-treated clothing could provide protection to individuals from Ae. aegypti that show permethrin resistance. Additionally, it could continue to provide protection even after the clothing has been worn. Field trials are urgently needed to determine whether clothing can protect against dengue and Zika

    Do temporal changes in vegetation structure additional to time since fire predict changes in bird occurrence?

    Get PDF
    Fire is a major ecological process in ecosystems globally. Its impacts on fauna can be both direct (e.g. mortality) and indirect (e.g. altered habitat), resulting in population recovery being driven by several possible mechanisms. Separating direct from indirect impacts of fire on faunal population recovery can be valuable in guiding management of biodiversity in fire-prone environments. However, resolving the influence of direct and indirect processes remains a key challenge because many processes affecting fauna can change concomitantly with time since fire. We explore the mechanisms influencing bird response to fire by posing the question: Can temporal changes in vegetation structure predict changes in bird occurrence on sites, and can these be separated from other temporal changes using the surrogate of time since fire? We conducted a 12-year study of bird and vegetation responses to fire at 124 sites across six vegetation classes in Booderee National Park, Australia. Approximately half of these sites, established in 2002, were burnt by a large (> 3000 ha) wildfire in 2003. To disentangle collinear effects of temporal changes in vegetation and direct demographic effects on population recovery that are subsumed by time since fire, we incorporated both longitudinal and cross-sectional vegetation effects in addition to time since fire within logistic structural equation models. We identified temporal changes in vegetation structure and richness of plant and bird species that characterized burnt and unburnt sites in all vegetation classes. For nine bird species, a significant component of the year trend was driven by temporal trends in one of three vegetation variables (number of understory or midstory plant species, or midstory cover). By contrast, we could not separate temporal effects between time since fire and vegetation attributes for bird species richness, reporting rate, and the occurrence of 11 other bird species. Our findings help identify species for which indirect effects of vegetation dominate recovery and thus may benefit from vegetation management where conservation actions are required and, conversely, those species for which direct effects of time since fire drive recovery, where simply leaving a system to recover following the last disturbance will be sufficient.This project was supported by grants by the Australian Research Council, the Department of the Environment, and the Department of Defence
    • …
    corecore