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Comparison between antigen and Aalelic HLA mismatches, and the risk of acute rejection in kidney transplant recipients
Get PDFDeceased donor kidney allocation relies on HLA compatibility at the antigen level, as optimal matching reduces the risk of acute rejection. Whether HLA allele-level mismatches improve, the prediction of acute rejection after transplantation remains unclear. Using data from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) from 2017 to 2020, HLA antigenic and allelic mismatches between recipients and deceased donors were calculated with imputation of two-field allelic equivalents undertaken where required. The discordance between antigen and allele mismatches was calculated, and oblique random survival forest models were used to predict acute rejection. Predictive performance of antigen (HLA-A, -B, -DRB1 and -DQB1), allele (HLA-A, -B, -DRB1 and -DQB1) and extended allele (HLA-A, -B, -C, -DRB1, -DQA1 and -DQB1) models was examined using concordance index and integrated Brier scores, with variable importance calculated using permutation-based methods. Among 2644 recipients followed for a median of 1.7 years, 521 recipients (20%) experienced acute rejection. Discordant numbers of antigenic and allelic mismatches occurred in 8%, 9%, 24% and 17% of HLA-A, -B, -DRB1 and -DQB1 loci, respectively. Predictive performances were similar across all models, with concordance indices of 0.62–0.63 and integrated Brier scores of 0.09. HLA-DRB1 and -DQB1 mismatches were the strongest predictors of acute rejection across models. In patients matched at the HLA-DRB1 or -DQB1 antigen, those with allelic mismatches had similar incidences of rejection compared to those without. Allelic-level assessment of HLA compatibility did not improve the prediction of acute rejection and may disadvantage certain recipients by reclassifying them into higher mismatch categories in allocation algorithms without providing clear clinical benefit
Cutting through the fog: Recognising brain fog as a significant public health concern
Get PDFBrain fog is a highly common condition that can have significant impacts on quality of life and functioning. Most people will experience a condition, illness, or infection that might result in the development of brain fog. We provide a call to action to minimise the impacts of brain fog
Design of an improved robust fractional-order PID controller for buck–boost converter using snake optimization algorithm
Get PDFWith the increasing complexity of modern power systems, effective control of DC–DC converters has become crucial to ensure stability and efficiency. This paper focuses on optimizing the parameters of a known fractional-order proportional–integral–derivative (FOPID) controller for the control of a DC–DC buck–boost converter. The control of a DC–DC buck–boost converter is achieved using aFOPID approach. The gains of this technique have been enhanced utilizing the snake optimization (SO) algorithm. This converter exhibits unfavourable behaviour due to its non-minimum structure, necessitating a well-regulated controller to guarantee stability. The fractional concept is suggested here to enhance the dynamics of the classical PID controller, leveraging its simplicity and minimizing computational load in real-time applications. The fractional idea is an advantageous method that offers several benefits, such as reduced overshoot and settling time, enhanced frequency response, non-integer order dynamics, and, more importantly, higher robustness to noise and parametric variation. Despite the advantages reported by this control technique, a proper gain tuning is needed to enhance its dynamical performance and decrease its sensitivity to error. Thus, a modern algorithm known as SO tunes the values of the gains in the controller to affect the efficiency of this method. This algorithm is a novel strategy with numerous merits compared to others, using its bi-directional search and elite opposition-based learning strategies. The SO algorithm and its variants offer a promising alternative for solving optimization problems, combining efficiency, adaptability, and competitive performance. The contribution of this work lies in utilizing the SO algorithm to enhance the performance of the FOPID controller, enabling faster convergence and improved stability under varying operating conditions. The proposed approach is validated through both simulation and hardware-in-loop experiments, demonstrating superior performance compared to conventional control methods
Health outcomes of sarcopenia: A consensus report by the outcome working group of the Global Leadership Initiative in Sarcopenia (GLIS)
Get PDFThe Global Leadership Initiative in Sarcopenia (GLIS) aims to standardize the definition and diagnostic criteria for sarcopenia into one unifying, common classification. Among other actions to achieve this objective, the GLIS has organized three different working groups (WGs), with the WG on outcomes of sarcopenia focusing on reporting its health outcomes to be measured in clinical practice once a diagnosis has been established. This includes sarcopenia definitions that better predict health outcomes, the preferred tools for measuring these outcomes, and the cutoffs defining normal and abnormal values. The present article synthesizes discussions and conclusions from this WG, composed of 13 key opinion leaders from different continents worldwide. Results rely on systematic reviews, meta-analyses, and relevant cohort studies in the field. With a high level of evidence, sarcopenia is significantly associated with a reduced quality of life, a higher risk of falls and fractures and a higher risk of mortality. Sarcopenia has been moderately associated with a higher risk of reduced instrumental activities of daily living (IADL). However, the GLIS WG found only inconclusive level of evidence to support associations between sarcopenia and higher risks of hospitalization, nursing home admission, mobility impairments, and reduced basic activities of daily living (ADL). This limitation underscores the scarcity of longitudinal studies, highlighting a barrier to understanding its progression and implications over time
Machine learning-based seismic response forecasting using feature mapping algorithms and scientometric analysis of nailed vertical excavation in a soil mass
Get PDFSeismic analysis often involves significant uncertainty and requires detailed observations. The traditional approaches are constrained by unclear mechanisms and imprecise models to predict the stability of geostructures. The research gap between the accuracy of observed and predicted values can be bridged by employing artificial intelligence-based machine learning (ML) models. The seismic displacement of the nailed soil wall obtained from experimental studies were assessed using suitable ML approaches. Laboratory studies revealed that the critical acceleration was increased by 32% on the inclusion of nails of reinforcement length to excavation height ratio (L/H) to 0.6, and by 17% when the (L/H) was increased from 0.6 to 0.8. The research was focussed on the incorporation of ML techniques for effective data processing and modeling algorithms to extract data. The influence of the design parameters on the seismic stability of nailed soil excavation is investigated using multivariate regression analysis. The ML algorithms, RBF kernel and random Fourier features consistently delivered strong performance pairing with linear regression algorithm. The optimal prediction model indicated 11.34% variation from the target variables with a positive R-squared value. A comparative analysis demonstrated the applicability and generalizability of ML modeling for outcome prediction, benefiting similar studies
Nitrogen processes within tropical mangroves in Australia
Get PDFCoastal wetlands have long been identified as ecosystems that can ameliorate N inputs into the ocean. The processes associated with N uptake, transformation, and losses are relatively well understood for temperate wetlands; however, information on tropical wetlands is scarce. In this study, we conducted a whole ecosystem approach to measure N processes within tropical mangroves in the Moresby estuary in northeast Australia. We measured N stocks (trees and soils), inputs from sedimentation, fixation, and accumulation as woody biomass, and outputs through denitrification, anammox, and soil respiration (N2O emissions). Potential denitrification was detected along anammox (average, min-max) at 883 (485–1,450) gN ha−1 day−1, followed by sediment accumulation with 108 (0–375) gN ha−1 day−1, and tree uptake with 93 (13–153) gN ha−1 day−1. Lower rates were found for N fixation with 45 (0–260) gN ha−1 day−1 and soil respiration as N2O with uptakes of −0.36 (−2.7 – 0.40) gN ha−1 day−1. Overall, mangroves in the Moresby estuary are fixing some N in their standing litter while removing NO3 and NH4+ from the water column through denitrification and anammox, temporarily storing N as woody biomass, and accumulating particulate N in their sediments. These mangroves are also functioning as sinks of N2O. Thus, the protection and restoration of these mangroves provide water quality and climate benefits
Recommendations for strengthening blue carbon science
Get PDFBlue carbon (BC) habitats (e.g., mangroves, tidal marshes, and seagrasses) are important CO2 sinks but are among the most threatened ecosystems on Earth. Substantial research over the last decade has quantified BC to evaluate the climate benefits associated with habitat conservation and restoration. However, the exponential growth in BC science has resulted in differing approaches that hinder comparison across studies and increase uncertainty. Here, we synthesized existing data to depict the range of uncertainty associated to different BC methodologies and argue that cumulative biases linked to multiple methodologies can result in BC estimates differing by up to 10-fold. We identified 14 common research procedures that can be improved to strengthen BC biophysical assessments and support implementation of BC projects, and outlined good practices to align research with policy, management, and ethical values. Standardization of practices will help generate high-quality BC projects that can deliver multiple co-benefits for humans and the environment
Sleep in residential aged care: A secondary qualitative analysis of data from the Australian Royal Commission into Aged Care Quality and Safety
Get PDFBackground:
Sleep is a crucial healing and restorative component of older person care but is often negatively impacted through the effects of institutionalization in residential aged care (RAC). Currently, information about how sleep occurs is limited.
Methods:
Through the lens of person-centered care, this study examined submissions to the Australian Royal Commission into Aged Care Quality and Safety. The Commission was established in 2018 with the aim of protecting and improving the safety, quality of life, and well-being of people receiving aged care. The commission received 10 000+ submissions from a range of stakeholders, including consumers, family members, expert witnesses, healthcare professionals, and industry. Using a big qualitative data approach with 33 sleep-related keywords, submissions were analyzed using thematic analysis to understand how institutional practices impact individual sleep experiences.
Results:
Three themes were identified highlighting tensions between institutional requirements and person-centered care: (1) Care practices of RAC staff may impact residents’ sleep, (2) Tensions between provision of overnight care and preservation of sleep, and (3) The dignity of choice of residents including autonomy of sleep timing and their sleep environment.
Conclusion:
Opportunities to improve the quality of sleep experience and associated outcomes in Australian RAC exist. Improved staffing, planning for person-centered timing of care, and addressing the competing tensions of safety surveillance activities and person-centered care implementation in a home environment are needed
The effect of climate change on different types of international visitors in Western Australia
Get PDFThis paper examines the effects of climate change on tourist arrivals to Western Australia, which we classify according to the purpose of their visit (business, education, holiday, visitors of friends and relatives (VFR), and employment). We construct a temperature variability indicator that measures the deviation of extreme temperatures from the average temperature. Overall, the results reveal that temperature variabilities have long-term diminishing effects on tourist arrivals, specifically VFR, visitors for employment and education. Surprisingly, unusually low-temperature variability negatively affects tourist arrivals more than unusually high-temperature variability. This suggests that cooler temperatures than expected could lead to tourists’ dissatisfaction and reduce the perceived attractiveness of the destination
What is informal sport? Negotiating contemporary sporting forms
Get PDFAs traditional sport participation stagnates or declines, flexible informal sporting forms are increasingly a focus for those with a vested interest in maximising participation in sport and physical activity. This study critiques existing definitions of informal sport as overly binary, largely unhelpful, and conceptually diffuse. We propose a more nuanced understanding of informal sport that explores participant proximity to the negotiation of practices that come to shape the sporting experience and therefore levels of (in)formality. Drawing on qualitative data from three Australian case studies, we examine how participants negotiate key features of their sporting experience, such as affiliation, environment, scheduling, competition, rules, social relations, and dress. Findings reveal that informal sport is characterised by participants’ proximity to the negotiation of these features, challenging the binary formal-informal distinction. Understanding sport as a spectrum of negotiated practices and decision-making, provides a useful framework for understanding (in)formality. A sport sector that pays attention to the types of negotiations people want to have some control over, whilst negotiating other elements on their behalf, will be well positioned to respond effectively to the changing nature of sport