632 research outputs found
Integration of a Stereo Vision System and GPS Data for Recording the Position of Feature Points in a Fixed World Coordinate System
This paper describes a laboratory system for recovering the global coordinates of feature points obtained from a moving camera. The prototype includes a stereo vision system combined with an overhead camera, which mimics a GPS receiver. The stereo vision system provides three dimensional feature point coordinates relative to the position of the cameras and the overhead camera provides three-dimensional coordinates of the camera in a “global” coordinate system. The fusion of these data provides three-dimensional feature point coordinates in a fixed origin global coordinate system
Projecting the future: modelling Australian dialysis prevalence 2021–30
To project the prevalence of people receiving dialysis in Australia for 2021–30 to inform service planning and health policy. Methods. Estimates were based on data from 2011 to 2020 from the Australia & New Zealand Dialysis & Transplant (ANZDATA) Registry and the Australian Bureau of Statistics. We projected dialysis and functioning kidney transplant recipient populations for the years 2021–30. Discrete-time, non-homogenous Markov models were built on probabilities for transition between three mutually exclusive states (Dialysis, Functioning Transplant, Death), for five age groups. Two scenarios were employed – stable transplant rate vs a continued increase – to assess the impact of these scenarios on the projected prevalences. Results. Models projected a 22.5–30.4% growth in the dialysis population from 14 554 in 2020 to 17 829 (‘transplant growth’) – 18 973 (‘transplant stable’) by 2030. An additional 4983–6484 kidney transplant recipients were also projected by 2030. Dialysis incidence per population increased and dialysis prevalence growth exceeded population ageing in 40–59 and 60–69 year age groups. The greatest dialysis prevalence growth was seen among those aged ≥70 years. Conclusion. Modelling of the future prevalence of dialysis use highlights the increasing demand on services expected overall and especially by people aged ≥70 years. Appropriate funding and healthcare planning must meet this demand.Dominic Keuskamp, Christopher E. Davies, Georgina L. Irish, Shilpanjali Jesudason and Stephen P. McDonal
A simple inert model solves the little hierarchy problem and provides a dark matter candidate
We discuss a minimal extension to the standard model in which two singlet
scalar states that only interacts with the Higgs boson is added. Their masses
and interaction strengths are fixed by the two requirements of canceling the
one-loop quadratic corrections to the Higgs boson mass and providing a viable
dark matter candidate. Direct detection of the lightest of these new states in
nuclear scattering experiments is possible with a cross section within reach of
future experiments.Comment: Finite corrections included. Model modified. Conclusion unchange
Parenthood and pregnancy in Australians receiving treatment for end-stage kidney disease: protocol of a national study of perinatal and parental outcomes through population record linkage.
Introduction Achieving parenthood is challenging in individuals receiving renal replacement therapy (RRT; dialysis or kidney transplantation) for end-stage kidney disease. Decision-making regarding parenthood in RRT recipients should be underpinned by robust data, yet there is limited data on parental factors that drive adverse health outcomes. Therefore, we aim to investigate the perinatal risks and outcomes in parents receiving RRT. Methods and analysis This is a multijurisdictional probabilistic data linkage study of perinatal, hospital, birth, death and renal registers from 1991 to 2013 from New South Wales, Western Australia, South Australia and the Australian Capital Territory. This study includes all babies born ≥20 weeks’ gestation or 400 g birth weight captured through mandated data collection in the perinatal data sets. Through linkage with the Australian and New Zealand Dialysis and Transplant (ANZDATA) registry, babies exposed to RRT (and their parents) will be compared with babies who have not been exposed to RRT (and their parents) to determine obstetric and fetal outcomes, birth rates and fertility rates. One of the novel aspects of this study is the method that will be used to link fathers receiving RRT to the mothers and their babies within the perinatal data sets, using the birth register, enabling the identification of family units. The linked data set will be used to validate the parenthood events directly reported to ANZDATA. Ethics and dissemination Ethics approval was obtained from Human Research Ethics Committees (HREC) and Aboriginal HREC in each jurisdiction. Findings of this study will be disseminated at scientific conferences and in peer-reviewed journals in tabular and aggregated forms. De-identified data will be presented and individual patients will not be identified. We will aim to present findings to relevant stakeholders (eg, patients, clinicians and policymakers) to maximise translational impact of research findings.Erandi Hewawasam, Aarti Gulyani, Christopher E Davies, Elizabeth Sullivan, Sally Wark, Philip A Clayton, Stephen P McDonald, Shilpanjali Jesudaso
A multi-scale comparison of modeled and observed seasonal methane emissions in northern wetlands
Wetlands are the largest global natural methane (CH4/ source, and emissions between 50 and 70° N latitude contribute 10-30% to this source. Predictive capability of land models for northern wetland CH4 emissions is still low due to limited site measurements, strong spatial and temporal variability in emissions, and complex hydrological and biogeochemical dynamics. To explore this issue, we compare wetland CH4 emission predictions from the Community Land Model 4.5 (CLM4.5-BGC) with siteto regional-scale observations. A comparison of the CH4 fluxes with eddy flux data highlighted needed changes to the model's estimate of aerenchyma area, which we implemented and tested. The model modification substantially reduced biases in CH4 emissions when compared with CarbonTracker CH4 predictions. CLM4.5 CH4 emission predictions agree well with growing season (May-September) CarbonTracker Alaskan regional-level CH4 predictions and sitelevel observations. However, CLM4.5 underestimated CH4 emissions in the cold season (October-April). The monthly atmospheric CH4 mole fraction enhancements due to wetland emissions are also assessed using the Weather Research and Forecasting-Stochastic Time-Inverted Lagrangian Transport (WRF-STILT) model coupled with daily emissions from CLM4.5 and compared with aircraft CH4 mole fraction measurements from the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) campaign. Both the tower and aircraft analyses confirm the underestimate of cold-season CH4 emissions by CLM4.5. The greatest uncertainties in predicting the seasonal CH4 cycle are from the wetland extent, coldseason CH4 production and CH4 transport processes. We recommend more cold-season experimental studies in highlatitude systems, which could improve the understanding and parameterization of ecosystem structure and function during this period. Predicted CH4 emissions remain uncertain, but we show here that benchmarking against observations across spatial scales can inform model structural and parameter improvements
Expression of mucin synthesis and secretion in human tracheobronchial epithelial cells grown in culture.
The effects of culture conditions on growth and differentiation of human tracheobronchial epithelial (HTBE) cells have been defined. Epithelial cells were dissociated from tissues by protease treatment and were plated on tissue culture dishes in F12 medium supplemented with insulin, transferrin, epidermal growth factor, hydrocortisone, cholera toxin, bovine hypothalamus extract, and retinol. HTBE cells did not express any mucociliary function (ciliogenesis or mucin secretion) on tissue culture plastic, but they could be passaged 3 to 5 times with a total of 10 to 25 population doublings. Cells from early passages re-express both these functions when transplanted to tracheal grafts. When tissue culture plates were coated with collagen film or collagen gel substrata, cell attachment and proliferation were stimulated. However, the expression of mucous cell function in culture occurred only when cells were plated on collagen gel substrata and vitamin A (retinol) was present in the medium. Mucous cell differentiation under optimal conditions was defined by ultrastructural studies, by immunologic studies with mucin-specific monoclonal antibodies, and by carbohydrate and amino acid compositional analyses of mucin-like glycoproteins purified from culture medium. These results demonstrate for the first time that HTBE cells can express mucin synthesis and secretion under appropriate culture conditions
Postnatal Zika virus infection is associated with persistent abnormalities in brain structure, function, and behavior in infant macaques
The Zika virus (ZIKV) epidemic is associated with fetal brain lesions and other serious birth defects classified as congenital ZIKV syndrome. Postnatal ZIKV infection in infants and children has been reported; however, data on brain anatomy, function, and behavioral outcomes following infection are absent. We show that postnatal ZIKV infection of infant rhesus macaques (RMs) results in persistent structural and functional alterations of the central nervous system compared to age-matched controls. We demonstrate ZIKV lymphoid tropism and neurotropism in infant RMs and histopathologic abnormalities in the peripheral and central nervous systems including inflammatory infiltrates, astrogliosis, and Wallerian degeneration. Structural and resting-state functional magnetic resonance imaging (MRI/rs-fMRI) show persistent enlargement of lateral ventricles, maturational changes in specific brain regions, and altered functional connectivity (FC) between brain areas involved in emotional behavior and arousal functions, including weakened amygdala-hippocampal connectivity in two of two ZIKV-infected infant RMs several months after clearance of ZIKV RNA from peripheral blood. ZIKV infection also results in distinct alterations in the species-typical emotional reactivity to acute stress, which were predicted by the weak amygdala-hippocampal FC. We demonstrate that postnatal ZIKV infection of infants in this model affects neurodevelopment, suggesting that long-term clinical monitoring of pediatric cases is warranted
Interactions between donor age and 12-month estimated glomerular filtration rate on allograft and patient outcomes after kidney transplantation
Reduced estimated glomerular filtration rate (eGFR) at 12-months after kidney transplantation is associated with increased risk of allograft loss, but it is uncertain whether donor age and types modify this relationship. Using Australia and New Zealand registry data, multivariable Cox proportional modelling was used to examine the interactive effects between donor age, types and 12-month eGFR on overall allograft loss. We included 11,095 recipients (4,423 received live-donors). Recipients with lowest 12-month eGFR (60 ml/min/1.73 m²) was 0.67 [0.62–0.74]. The association of 12-month eGFR and allograft loss was modified by donor age (but not donor types) where a higher risk of allograft loss in recipients with lower compared with higher 12-month eGFR being most pronounced in the younger donor age groups (p 60 ml/min/1.73 m², and the magnitude of the increased risk is most marked among recipients with younger donors. Careful deliberation of other factors including donor age when considering eGFR as a surrogate for clinical endpoints is warranted.Wai H. Lim, Esther Ooi, Helen L. Pilmore, David W. Johnson, Stephen P. McDonald, Philip Clayton, Carmel Hawley, William R. Mulley, Ross Francis, Michael G. Collins, Bryon Jaques, Nicholas G. Larkins, Christopher E. Davies, Kate Wyburn, Steve J. Chadban and Germaine Won
Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV
We report the results of a study of color coherence effects in ppbar
collisions based on data collected by the D0 detector during the 1994-1995 run
of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8
TeV. Initial-to-final state color interference effects are studied by examining
particle distribution patterns in events with a W boson and at least one jet.
The data are compared to Monte Carlo simulations with different color coherence
implementations and to an analytic modified-leading-logarithm perturbative
calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters
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