13,917 research outputs found

    A two-species stage-structured model for West Nile virus transmission

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    We develop a host–vector model of West Nile virus (WNV) transmission that incorporates multiple avian host species as well as host stage-structure (juvenile and adult stages), allowing for both species-specific and stage-specific biting rates of vectors on hosts. We use this ordinary differential equation model to explore WNV transmission dynamics that occur between vectors and multiple structured host populations as a result of heterogeneous biting rates on species and/or life stages. Our analysis shows that increased exposure of juvenile hosts generally results in larger outbreaks of WNV infectious vectors when compared to differential host species exposure. We also find that increased juvenile exposure is an important mechanism for determining the effect of species diversity on the disease risk of a community

    Two sides of the coin:Patient and provider perceptions of health care delivery to patients from culturally and linguistically diverse backgrounds

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    BACKGROUND: Australia is a culturally diverse nation with one in seven Australians born in a non-English speaking country. Culturally and Linguistically Diverse (CALD) populations are at a high risk of developing preventable chronic diseases such as cardiovascular disease, type 2 diabetes mellitus, renal disease, and chronic respiratory disease, especially communities from the Pacific Islands, the Middle East, North Africa, the Indian subcontinent and China. Previous studies have shown that access to services may be a contributing factor. This study explores the experiences, attitudes and opinions of immigrants from different cultural and linguistic backgrounds and their health care providers with regard to chronic disease care. METHODS: Five focus groups were conducted comprising participants from an Arabic speaking background, or born in Sudan, China, Vietnam or Tonga. A total of 50 members participated. All focus groups were conducted in the participants’ language and facilitated by a trained multicultural health worker. In addition, 14 health care providers were interviewed by telephone. Interviews were digitally recorded and transcribed. All qualitative data were analysed with the assistance of QSR NVivo 8 software. RESULTS: Participants were generally positive about the quality and accessibility of health services, but the costs of health care and waiting times to receive treatment presented significant barriers. They expressed a need for greater access to interpreters and culturally appropriate communication and education. They mentioned experiencing racism and discriminatory practices. Health professionals recommended recruiting health workers from CALD communities to assist them to adequately elicit and address the needs of patients from CALD backgrounds. CONCLUSIONS: CALD patients, carers and community members as well as health professionals all highlighted the need for establishing culturally tailored programs for chronic disease prevention and management in CALD populations. Better health care can be achieved by ensuring that further investment in culturally specific programs and workforce development is in line with the number of CALD communities and their needs

    Age-dependent transient shear banding in soft glasses

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    We study numerically the formation of long-lived transient shear bands during shear startup within two models of soft glasses (a simple fluidity model and an adapted `soft glassy rheology' model). The degree and duration of banding depends strongly on the applied shear rate, and on sample age before shearing. In both models the ultimate steady flow state is homogeneous at all shear rates, consistent with the underlying constitutive curve being monotonic. However, particularly in the SGR case, the transient bands can be extremely long lived. The banding instability is neither `purely viscous' nor `purely elastic' in origin, but is closely associated with stress overshoot in startup flow.Comment: 4 pages, 3 figure

    Detecting Differential Rotation and Starspot Evolution on the M dwarf GJ 1243 with Kepler

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    We present an analysis of the starspots on the active M4 dwarf GJ 1243, using four years of time series photometry from Kepler. A rapid P=0.592596±0.00021P = 0.592596\pm0.00021 day rotation period is measured due to the \sim2.2\% starspot-induced flux modulations in the light curve. We first use a light curve modeling approach, using a Monte Carlo Markov Chain sampler to solve for the longitudes and radii of the two spots within 5-day windows of data. Within each window of time the starspots are assumed to be unchanging. Only a weak constraint on the starspot latitudes can be implied from our modeling. The primary spot is found to be very stable over many years. A secondary spot feature is present in three portions of the light curve, decays on 100-500 day timescales, and moves in longitude over time. We interpret this longitude shearing as the signature of differential rotation. Using our models we measure an average shear between the starspots of 0.0047 rad day1^{-1}, which corresponds to a differential rotation rate of ΔΩ=0.012±0.002\Delta\Omega = 0.012 \pm 0.002 rad day1^{-1}. We also fit this starspot phase evolution using a series of bivariate Gaussian functions, which provides a consistent shear measurement. This is among the slowest differential rotation shear measurements yet measured for a star in this temperature regime, and provides an important constraint for dynamo models of low mass stars.Comment: 13 pages, 7 figures, ApJ Accepte
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