Many studies bias correct daily precipitation from climate models to match the observed precipitation statistics, and the bias corrected data are then used for various modelling applications. This ...paper presents a review of recent methods used to bias correct precipitation from regional climate models (RCMs). The paper then assesses four bias correction methods applied to the weather research and forecasting (WRF) model simulated precipitation, and the follow-on impact on modelled runoff for eight catchments in southeast Australia. Overall, the best results are produced by either quantile mapping or a newly proposed two-state gamma distribution mapping method. However, the differences between the methods are small in the modelling experiments here (and as reported in the literature), mainly due to the substantial corrections required and inconsistent errors over time (non-stationarity). The errors in bias corrected precipitation are typically amplified in modelled runoff. The tested methods cannot overcome limitations of the RCM in simulating precipitation sequence, which affects runoff generation. Results further show that whereas bias correction does not seem to alter change signals in precipitation means, it can introduce additional uncertainty to change signals in high precipitation amounts and, consequently, in runoff. Future climate change impact studies need to take this into account when deciding whether to use raw or bias corrected RCM results. Nevertheless, RCMs will continue to improve and will become increasingly useful for hydrological applications as the bias in RCM simulations reduces.
This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel ...element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging through depth.
Clinical evidence needed for risks of PPE Kua, J.; Nurmi, E.; Wong, D. J. N. ...
Anaesthesia,
March 2023, 2023-03-00, 20230301, Letnik:
78, Številka:
3
Journal Article
Objective
To determine the prevalence of obesity within a population of pleasure horses and ponies in Victoria, Australia, and to compare owners’ perceptions of their animals’ body condition with ...researchers’ assessments.
Design
An observational study plus owner questionnaire.
Methods
Ten Pony Club rallies in different regions of Victoria were attended. Information regarding 229 horses and ponies were obtained from owner questionnaires, and owners’ perceptions of the current body condition of their animals were assessed using a visual analogue scale. Body condition score (BCS) was assessed by the researchers using the modified Henneke method.
Results
The prevalence of researcher‐assessed obesity (BCS ≥7/9) in the total surveyed population was 23.1%. A higher prevalence of obesity was identified in Shetland ponies (71.5%) and other pony types (32.0%) compared with horse breeds (9.3%). Owners perceived their animals to be in significantly lower body condition compared with the researchers’ assessments (P < 0.001).
Conclusion
Although the overall prevalence of obesity within Australian pleasure horses and ponies was 24.5%, a considerably higher proportion of pony breeds fell into this category. Owners frequently underestimated their own animal's body condition. Knowing the prevalence of obesity in this population and understanding how owners perceive the body condition of their animals may help with targeting education around preventative health care, with the aim of reducing the risk of conditions such as insulin dysregulation and laminitis.
We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease ...(AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases.
An important factor controlling catchment-scale water balance is the seasonal variation of climate. The aim of this study is to investigate the effect of the seasonal distributions of water and ...energy, and their interactions with the soil moisture store, on mean annual water balance in Australia at catchment scales using a stochastic model of soil moisture balance with seasonally varying forcing. The rainfall regime at 262 catchments around Australia was modeled as a Poisson process with the mean storm arrival rate and the mean storm depth varying throughout the year as cosine curves with annual periods. The soil moisture dynamics were represented by use of a single, finite water store having infinite infiltration capacity, and the potential evapotranspiration rate was modeled as an annual cosine curve. The mean annual water budget was calculated numerically using a Monte Carlo simulation. The model predicted that for a given level of climatic aridity the ratio of mean annual evapotranspiration to rainfall was larger where the potential evapotranspiration and rainfall were in phase, that is, in summer-dominant rainfall catchments, than where they were out of phase. The observed mean annual evapotranspiration ratios have opposite results. As a result, estimates of mean annual evapotranspiration from the model compared poorly with observational data. Because the inclusion of seasonally varying forcing alone was not sufficient to explain variability in the mean annual water balance, other catchment properties may play a role. Further analysis showed that the water balance was highly sensitive to the catchment-scale soil moisture capacity. Calibrations of this parameter indicated that infiltration-excess runoff might be an important process, especially for the summer-dominant rainfall catchments; most similar studies have shown that modeling of infiltration-excess runoff is not required at the mean annual timescale.
The Murray–Darling Basin (MDB) in south-eastern Australia has been in the grip of a serious drought for over a decade. Recent reductions in runoff have been unprecedented in the historical record. We ...test annual time series of rainfall and runoff from 1895 to 2006 for the presence of step changes and trends in order to place recent years in the context of the historical record, and characterise the severity of the recent low rainfall and runoff using average recurrence intervals. The largest signal identified in historical rainfall and runoff is a step-change increase in rainfall and runoff occurring in the mid-1940s. However, other dry periods comparable to the recent dry sequence are evident in the historical record, particularly at the beginning of the 20th century and around 1936–1945. The recent reduction in rainfall and runoff is most severe in the southernmost parts of the MDB, with the runoff reduction being significantly more severe than the rainfall reduction. The average recurrence interval of the reduction in mean annual rainfall during 1997–2006 in the southernmost parts of the MDB is up to 100
years, whereas the average recurrence interval of the reduction in mean annual runoff during 1997–2006 is more than 300
years. We explore possible reasons for the larger than expected runoff decrease including proportionally larger decreases in autumn and winter rainfall in the winter-dominant rainfall regime of the southern MDB, less interannual variability of rainfall and increased temperatures.
This article reports a technique for near-surface ultrasonic array imaging. Information equivalent to an undelayed full matrix of inter-element responses is produced through cross-correlation of a ...later time diffuse full matrix. This reconstructed full matrix lacks the nonlinear effects of early time saturation present in a directly acquired response. Consequently the near-surface material information usually obscured by this effect is retrieved. Furthermore it is shown that a hybrid full matrix formed through a temporally weighted sum of coherent and reconstructed matrices allows for effective near-surface and bulk material imaging from a single direct-contact experimental realisation.
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