269 research outputs found
Synthetic Data as a Strategy to Resolve Data Privacy and Confidentiality Concerns in the Sport Sciences: Practical Examples and an R Shiny Application
There has been a proliferation in technologies in the sport performance environment that collect increasingly largerquantities of athlete data. These data have the potential to be personal, sensitive, and revealing and raise privacy and confidentialityconcerns. A solution may be the use of synthetic data, which mimic the properties of the original data. The aim of this study was toprovide examples of synthetic data generation to demonstrate its practical use and to deploy a freely available web-based R Shinyapplication to generate synthetic data. Methods: Openly available data from 2 previously published studies were obtained,representing typical data sets of (1) field- and gym-based team-sport external and internal load during a preseason period (n = 28)and (2) performance and subjective changes from before to after the posttraining intervention (n = 22). Synthetic data weregenerated using the synthpop package in R Studio software, and comparisons between the original and synthetic data sets weremade through Welch t tests and the distributional similarity standardized propensity mean squared error statistic. Results: Therewere no significant differences between the original and more synthetic data sets across all variables examined in both data sets(P > .05). Further, there was distributional similarity (ie, low standardized propensity mean squared error) between the originalobserved and synthetic data sets. Conclusions: These findings highlight the potential use of synthetic data as a practical solution toprivacy and confidentiality issues. Synthetic data can unlock previously inaccessible data sets for exploratory analysis andfacilitate multiteam or multicenter collaborations. Interested sport scientists, practitioners, and researchers should considerutilizing the shiny web application (SYNTHETIC DATAāavailable at https://assetlab.shinyapps.io/SyntheticData/)
A Dilatometric Study of Graphite Electrodes during Cycling with X-ray Computed Tomography
Graphite is the most commonly used anode material in commercial lithium-ion batteries (LiBs). Understanding the mechanisms driving the dimensional changes of graphite can pave the way to methods for inhibiting degradation pathways and possibly predict electrochemical performance loss. In this study, correlative microscopy tools were used alongside electrochemical dilatometry (ECD) to provide new insights into the dimensional changes during galvanostatic cycling. X-ray computed tomography (CT) provided a morphological perspective of the cycled electrode so that the effects of dilation and contraction on effective diffusivity and electrode pore phase volume fraction could be examined. During the first cycle, the graphite electrode underwent thickness changes close to 9% after lithiation and, moreover, it did not return to its initial thickness after subsequent delithiation. The irreversible dilation increased over subsequent cycles. It is suggested the primary reason for this dilation is electrode delamination. This is supported by the finding that the electrode porosity remained mostly unchanged during cycling, as revealed by X-ray CT
Synthetic Data as a Strategy to Resolve Data Privacy and Confidentiality Concerns in the Sport Sciences: Practical Examples and an R Shiny Application
PURPOSE: There has been a proliferation in technologies in the sport performance environment that collect increasingly larger quantities of athlete data. These data have the potential to be personal, sensitive, and revealing and raise privacy and confidentiality concerns. A solution may be the use of synthetic data, which mimic the properties of the original data. The aim of this study was to provide examples of synthetic data generation to demonstrate its practical use and to deploy a freely available web-based R Shiny application to generate synthetic data.
METHODS: Openly available data from 2 previously published studies were obtained, representing typical data sets of (1)Ā field- and gym-based team-sport external and internal load during a preseason period (n = 28) and (2)Ā performance and subjective changes from before to after the posttraining intervention (n = 22). Synthetic data were generated using the synthpop package in R Studio software, and comparisons between the original and synthetic data sets were made through Welch t tests and the distributional similarity standardized propensity mean squared error statistic.
RESULTS: There were no significant differences between the original and more synthetic data sets across all variables examined in both data sets (P > .05). Further, there was distributional similarity (ie,Ā low standardized propensity mean squared error) between the original observed and synthetic data sets.
CONCLUSIONS: These findings highlight the potential use of synthetic data as a practical solution to privacy and confidentiality issues. Synthetic data can unlock previously inaccessible data sets for exploratory analysis and facilitate multiteam or multicenter collaborations. Interested sport scientists, practitioners, and researchers should consider utilizing the shiny web application (SYNTHETIC DATA-available at https://assetlab.shinyapps.io/SyntheticData/)
Sex-biased parental care and sexual size dimorphism in a provisioning arthropod
The diverse selection pressures driving the evolution of sexual size dimorphism (SSD) have long been debated. While the balance between fecundity selection and sexual selection has received much attention, explanations based on sex-specific ecology have proven harder to test. In ectotherms, females are typically larger than males, and this is frequently thought to be because size constrains female fecundity more than it constrains male mating success. However, SSD could additionally reflect maternal care strategies. Under this hypothesis, females are relatively larger where reproduction requires greater maximum maternal effort ā for example where mothers transport heavy provisions to nests.
To test this hypothesis we focussed on digger wasps (Hymenoptera: Ammophilini), a relatively homogeneous group in which only females provision offspring. In some species, a single large prey item, up to 10 times the motherās weight, must be carried to each burrow on foot; other species provide many small prey, each flown individually to the nest.
We found more pronounced female-biased SSD in species where females carry single, heavy prey. More generally, SSD was negatively correlated with numbers of prey provided per offspring. Females provisioning multiple small items had longer wings and thoraxes, probably because smaller prey are carried in flight.
Despite much theorising, few empirical studies have tested how sex-biased parental care can affect SSD. Our study reveals that such costs can be associated with the evolution of dimorphism, and this should be investigated in other clades where parental care costs differ between sexes and species
Perceptual, metabolic, and neuromuscular responses to 10, 20, and 30% velocity loss thresholds during the barbell back-squat.
Introduction: This study compared the effects of 10, 20, and 30% velocity loss (VL) thresholds on differential ratings of perceived exertion (dRPE), lactate, and countermovement jump height (CMJ) during, immediately post-, and 24 hours post-five sets of the barbell back-squat.
Methods: In a randomised-crossover design, 15 resistance-trained males completed five sets of the back-squat with an initial mean concentric velocity of 0.70Ā±0.01 mĀ·s-1 and a set termination threshold of either 10% (0.63mĀ·s-1), 20% (0.56mĀ·s-1), or 30% (0.49mĀ·s-1) VL. External load was manipulated throughout each session to ensure the first repetition of sets 2-5 was 0.70Ā±0.06 mĀ·s-1. Participants provided fingertip lactate at the completion of each set, while CMJ was collected pre-, post-, and 24 hours post-exercise. dRPE for the legs and lungs was provided at the completion of the 5th set. Three minutes rest was provided between sets, while barbell velocity was assessed during exercise to guide set termination.
Results: Peak lactate responses in the 30% condition were likely (effect size Ā±90confidence interval: 1.45Ā±2.29) and almost certainly (4.56Ā±1.66) greater when compared to the 20% and 10%, respectively. In the 10, 20, and 30% conditions, CMJ height was reduced by 11.3% (Ā±2.4), 14.0% (Ā±3.3), and 20.0% (Ā±3.4), immediately post-exercise. Additionally, dRPE (mean (Ā±SD)) of the legs and lungs were, 10%: 27Ā±12 and 20Ā±9; 20%: 53Ā±16 and 50Ā±17; and 30%: 65Ā±18 and 65Ā±17. At 24 hours post-training, CMJ performance was, 10%: +0.7% (Ā±2.4); 20%: -0.6% (Ā±2.0); and 30%: -2.7% (Ā±2.7).
Conclusion: Different VL thresholds during the back-squat cause varying perceptual, metabolic, and neuromuscular responses. The use of 30% VL thresholds can cause substantially greater metabolic responses and potentially attenuate neuromuscular function at 24 hours post-training. Alternatively, a 10% VL can mitigate perceived exertion and changes in metabolic responses. These findings should be considered during the planning of velocity-based resistance training programmes
The Effects of 10%, 20%, and 30% Velocity Loss Thresholds on Kinetic, Kinematic, and Repetition Characteristics During the Barbell Back Squat.
PURPOSE: Prescribing resistance training using velocity loss thresholds can enhance exercise quality by mitigating neuromuscular fatigue. Since little is known regarding performance during these protocols, we aimed to assess the effects of 10%, 20%, and 30% velocity loss thresholds on kinetic, kinematic, and repetition characteristics in the free-weight back squat. METHODS: Using a randomised crossover design, sixteen resistance-trained men were recruited to complete five sets of the barbell back squat. Lifting load corresponded to a mean concentric velocity (MV) of ~0.70 mĀ·s-1 (115 Ā±22kg). Repetitions were performed until a 10%, 20% or 30% MV loss was attained. RESULTS: Set MV and power output were substantially higher in the 10% protocol (0.66 m.s-1 & 1341 W, respectively), followed by the 20% (0.62 & 1246) and 30% protocols (0.59 & 1179). There were no substantial changes in MV (-0.01- -0.02) or power output (-14- -55 W) across the five sets for all protocols and individual differences in these changes were typically trivial to small. Mean set repetitions were substantially higher in the 30% protocol (7.8), followed by the 20% (6.4) and 10% protocols (4.2). There were small to moderate reductions in repetitions across the five sets during all protocols (-39%, -31%, -19%, respectively) and individual differences in these changes were small to very large. CONCLUSIONS: Velocity training prescription maintains kinetic and kinematic output across multiple sets of the back squat, with repetition ranges being highly variable. Our findings therefore challenge traditional resistance training paradigms (repetition-based) and add support to a velocity-based approach
Application of velocity loss thresholds during free-weight resistance training : Responses and reproducibility of perceptual, metabolic, and neuromuscular outcomes.
The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 mĀ·s-1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmolĀ·L-1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8-11; B[La], 0.8-1.0; CMJ height, 1.6-2.0; CMJ PPO, 1.0-1.8; CMJ PCV, 0.04-0.06; CMJ 100ms-Impulse, 5.7-11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented
Oligogenic heterozygosity in individuals with high-functioning autism spectrum disorders
Autism spectrum disorders (ASDs) are a heterogeneous group of neuro-developmental disorders. While significant progress has been made in the identification of genes and copy number variants associated with syndromic autism, little is known to date about the etiology of idiopathic non-syndromic autism. Sanger sequencing of 21 known autism susceptibility genes in 339 individuals with high-functioning, idiopathic ASD revealed de novo mutations in at least one of these genes in 6 of 339 probands (1.8%). Additionally, multiple events of oligogenic heterozygosity were seen, affecting 23 of 339 probands (6.8%). Screening of a control population for novel coding variants in CACNA1C, CDKL5, HOXA1, SHANK3, TSC1, TSC2 and UBE3A by the same sequencing technology revealed that controls were carriers of oligogenic heterozygous events at significantly (P < 0.01) lower rate, suggesting oligogenic heterozygosity as a new potential mechanism in the pathogenesis of ASDs
TB infection prevention and control experiences of South African nurses - a phenomenological study
<p>Abstract</p> <p>Background</p> <p>The tuberculosis (TB) epidemic in South Africa is characterised by one of the highest levels of TB/HIV co-infection and growing multidrug-resistant TB worldwide. Hospitals play a central role in the management of TB. We investigated nurses' experiences of factors influencing TB infection prevention and control (IPC) practices to identify risks associated with potential nosocomial transmission.</p> <p>Methods</p> <p>The qualitative study employed a phenomenological approach, using semi-structured interviews with a quota sample of 20 nurses in a large tertiary academic hospital in Cape Town, South Africa. The data was subjected to thematic analysis.</p> <p>Results</p> <p>Nurses expressed concerns about the possible risk of TB transmission to both patients and staff. Factors influencing TB-IPC, and increasing the potential risk of nosocomial transmission, emerged in interconnected overarching themes. Influences related to the healthcare system included suboptimal IPC provision such as the lack of isolation facilities and personal protective equipment, and the lack of a TB-IPC policy. Further influences included inadequate TB training for staff and patients, communication barriers owing to cultural and linguistic differences between staff and patients, the excessive workload of nurses, and a sense of duty of care. Influences related to wider contextual conditions included TB concerns and stigma, and the role of traditional healers. Influences related to patient behaviour included late uptake of hospital care owing to poverty and the use of traditional medicine, and poor adherence to IPC measures by patients, family members and carers.</p> <p>Conclusions</p> <p>Several interconnected influences related to the healthcare system, wider contextual conditions and patient behavior could increase the potential risk of nosocomial TB transmission at hospital level. There is an urgent need for the implementation and evaluation of a comprehensive contextually appropriate TB IPC policy with the setting and auditing of standards for IPC provision and practice, adequate TB training for both staff and patients, and the establishment of a cross-cultural communication strategy, including rapid access to interpreters.</p
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