Living in Western Australia induces some physiological adaptations of seasonal acclimatisation in the surgical burns team.

Seasonal acclimatization is known to result in adaptations that can improve heat tolerance. Staff who operate on burn injuries are exposed to thermally stressful conditions and seasonal acclimatization may improve their thermoeffector responses during surgery. Therefore, the aim of this study was to assess the physiological and perceptual responses of staff who operate on burn injuries during summer and winter, to determine whether they become acclimatized to the heated operating theater. Eight staff members had physiological and perceptual responses compared during burn surgeries conducted in thermoneutral (CON: 24.1 ± 1.2°C, 45 ± 7% relative humidity [RH]) and heated (HOT: 31.3 ± 1.6°C, 44 ± 7% RH) operating theaters, in summer and winter. Physiological parameters that were assessed included core temperature, heart rate, total sweat loss, sweat rate, and urinary specific gravity. Perceptual responses included ratings of thermal sensation and comfort. In summer, CON compared to winter CON, baseline (85 ± 15 bpm VS 94 ± 18 bpm), mean (84 ± 16 bpm VS 93 ± 18 bpm), and peak HR (94 ± 17 bpm VS 105 ± 19 bpm) were lower (p < 0.05), whereas core temperature was not different between seasons in either condition (p > 0.05). In HOT, ratings of discomfort were higher in summer (15 ± 3) than winter (13 ± 3; p > 0.05), but ratings of thermal sensation and sweat rate were similar between seasons (p > 0.05). The surgical team in burns in Western Australia can obtain some of the physiological adaptations that result from seasonal acclimatization, but not all. That is most likely due to a lower than required amount of outdoor heat exposure in summer, to induce all physiological and perceptual adaptations.

Predictive modeling of ambulatory outcomes after spinal cord injury using machine learning.

STUDY DESIGN: Retrospective multi-site cohort study. OBJECTIVES: To develop an accurate machine learning predictive model using predictor variables from the acute rehabilitation period to determine ambulatory status in spinal cord injury (SCI) one year post injury. SETTING: Model SCI System (SCIMS) database between January 2000 and May 2019. METHODS: Retrospective cohort study using data that were previously collected as part of the SCI Model System (SCIMS) database. A total of 4523 patients were analyzed comparing traditional models (van Middendorp and Hicks) compared to machine learning algorithms including Elastic Net Penalized Logistic Regression (ENPLR), Gradient Boosted Machine (GBM), and Artificial Neural Networks (ANN). RESULTS: Compared with GBM and ANN, ENPLR was determined to be the preferred model based on predictive accuracy metrics, calibration, and variable selection. The primary metric to judge discrimination was the area under the receiver operating characteristic curve (AUC). When compared to the van Middendorp all patients (0.916), ASIA A and D (0.951) and ASIA B and C (0.775) and Hicks all patients (0.89), ASIA A and D (0.934) and ASIA B and C (0.775), ENPLR demonstrated improved AUC for all patients (0.931), ASIA A and D (0.965) ASIA B and C (0.803). CONCLUSIONS: Utilizing artificial intelligence and machine learning methods are feasible for accurately classifying outcomes in SCI and may provide improved sensitivity in identifying which individuals are less likely to ambulate and may benefit from augmentative strategies, such as neuromodulation. Future directions should include the use of additional variables to further refine these models.

Evaluating the nutrition and body mass index clinical link pathway in mental health and learning disability services: A mixed-methods study.

This research involved an evaluation of the Nutrition and Body Mass Index Clinical Link Pathway (NBMI CLiP) implemented in practice across Severe Mental Illness and/or learning disabilities ward in Tees, Esk and Wear Valleys NHS Foundation Trust (TEWV), to understand how the NBMI CLiP is used, inpatient staff feedback on the CLiP for supporting service users to manage their weight, and whether using the NBMI CLiP impacted on staffs' own weight management. To account for the uneven distribution of the secondary data, descriptive statistics such as medians and the inter-quartile range were conducted to assess anychanges in recording of Body Mass Index, nutrition screening (SANSI) and intervention planss. Staff survey data investigated barriers and facilitators to using the NBMI CLiP in practice and the impact on their own weight management. Secondary data analysis found most wards improved recording of BMI, SANSI and Intervention Planning. Forensic Learning Disabilities, Adult Learning Disabilities, mixed gender wards and North Yorkshire and York Operational Directorate indicated the greatest improvement. Survey results (n = 55) found three times as many participants (n = 12, 75%) found the NBMI CLiP easy or very easy to use; most fully understood it (n = 13, 81.20%) and were confident or very confident to carry out a SANSI Screen (n = 14, 87.50%) or a recovery focused intervention plan (n = 9, 56.20%). Open-text responses, analysed using content analysis, indicated a need for further training of staff on the NBMI CLiP. It is recommended that to support weight management across these wards, that a nudge or choice architecture approach to weight management is adopted, supported by training delivered by a dietitian.

Ribosome-Associated Vesicles promote activity-dependent local translation.

Local protein synthesis in axons and dendrites underpins synaptic plasticity. However, the composition of the protein synthesis machinery in distal neuronal processes and the mechanisms for its activity-driven deployment to local translation sites remain unclear. Here, we employed cryo-electron tomography, volume electron microscopy, and live-cell imaging to identify Ribosome-Associated Vesicles (RAVs) as a dynamic platform for moving ribosomes to distal processes. Stimulation via chemically-induced long-term potentiation causes RAV accumulation in distal sites to drive local translation. We also demonstrate activity-driven changes in RAV generation and dynamics in vivo , identifying tubular ER shaping proteins in RAV biogenesis. Together, our work identifies a mechanism for ribosomal delivery to distal sites in neurons to promote activity-dependent local translation.

Increased vascular stiffness in children exposed in utero but not children exposed postnatally to emissions from a coal mine fire.

Background: Chronic, low-intensity air pollution exposure has been consistently associated with increased atherosclerosis in adults. However, there was limited research regarding the implications of acute, high-intensity air pollution exposure during childhood. We aimed to determine whether there were any associations between early-life exposure to such an episode and early-life vascular function changes. Methods: We conducted a prospective cohort study of children (<9 years old) who lived in the vicinity of the Hazelwood coal mine fire (n = 206). Vascular function was measured using noninvasive diagnostic methods including carotid intima-media thickness and pulse wave velocity (PWV). Exposure estimates were calculated from prognostic models and location diaries during the exposure period completed by each participant's parent. Linear mixed-effects models were used to determine whether there were any associations between exposure and changes in vascular outcomes at the 3- and 7-year follow-ups and over time. Results: At the 7-year follow-up, each 10 µg/m3 increase in daily PM2.5 in utero was associated with increased PWV (ß = 0.13 m/s; 95% confidence interval [CI] = 0.02, 0.24; P = 0.02). The association between in utero exposure to daily PM2.5 was not altered by adjustment for covariates, body mass index, and maternal fire stress. Each 1 µg/m3 increase in background PM2.5 was associated with increased PWV (ß = 0.68 m/s; 95% CI = 0.10, 1.26; P = 0.025), in children from the in utero exposure group. There was a trend toward smaller PWV (ß = -0.17 m/s; 95% CI = -0.366, 0.02) from the 3- to 7-year follow-up clinic suggesting that the deficits observed previously in children exposed postnatally did not persist. Conclusion: There was a moderate improvement in vascular stiffness of children exposed to PM2.5 from a local coal mine fire in infancy. There was a mild increase in vascular stiffness in children exposed to PM2.5 from a local coal mine fire while their mothers were pregnant.

Surface-Area Enhanced Raman Spectroscopy of DNA in Porous Silica: A Quantitative and Reproducible Alternative to Plasmonic-Based SERS.

Despite the success of surface-enhanced Raman spectroscopy (SERS) for detecting DNA immobilized on plasmonic metal surfaces, its quantitative response is limited by the rapid falloff of enhancement with distance from the metal surface and variations in sensitivity that depend on orientation and proximity to plasmonic "hot spots". In this work, we assess an alternative approach for enhancing detection by immobilizing DNA on the interior surfaces of porous silica particles. These substrates provide over a 1000-fold greater surface area for detection compared to a planar support. The porous silica substrate is a purely dielectric material with randomly oriented internal surfaces, where scattering is independent of proximity and orientation of oligonucleotides relative to the silica surface. We characterize the quantitative response of Raman scattering from DNA in porous silica particles with sequences used in previous SERS investigations of DNA for comparison. The results show that Raman scattering of DNA in porous silica is independent of distance of nucleotides from the silica surface, allowing detection of longer DNA strands with constant sensitivity. The surface area enhancement within particles is reproducible (<4% particle-to-particle variation) owing to the uniform internal pore structure and surface chemistry of the silica support. DNA immobilization with a bis-thiosuccinimide linker provides a Raman-active internal standard for quantitative interpretation of Raman scattering results. Despite the high (30 mM) concentrations of immobilized DNA within porous silica particles, they can be used to measure nanomolar binding affinities of target molecules to DNA by equilibrating a very small number of particles with a sufficiently large volume of low-concentration solution of target molecules.

Structural characterization of antibody-responses from Zolgensma treatment provides the blueprint for the engineering of an AAV capsid suitable for redosing.

Monoclonal antibodies (mAbs) are useful tools to dissect the neutralizing antibody response against the adeno-associated virus (AAV) capsids used as gene therapy delivery vectors. This study structurally characterizes the interactions of 21 human-derived antibodies from patients treated with the AAV9 vector, Zolgensma ® , utilizing high-resolution cryo-electron microscopy. The majority of the bound antibodies do not conform to the icosahedral symmetry of the capsid, thus requiring localized reconstructions. These complex structures provide unprecedented details of the mAbs binding interfaces, with some antibodies inducing structural perturbations of the capsid upon binding. Key surface capsid amino acid residues were identified facilitating the design of capsid variants with an antibody escape phenotype, with the potential to expand the patient cohort treatable with AAV9 vectors to include those that were previously excluded due to their pre-existing neutralizing antibodies, and possibly also to those requiring redosing.

Coevolution with hosts underpins speciation in brood-parasitic cuckoos.

Coevolution between interacting species is thought to increase biodiversity, but evidence linking microevolutionary processes to macroevolutionary patterns is scarce. We leveraged two decades of behavioral research coupled with historical DNA analysis to reveal that coevolution with hosts underpins speciation in brood-parasitic bronze-cuckoos. At a macroevolutionary scale, we show that highly virulent brood-parasitic taxa have higher speciation rates and are more likely to speciate in sympatry than less-virulent and nonparasitic relatives. We reveal the microevolutionary process underlying speciation: Hosts reject cuckoo nestlings, which selects for mimetic cuckoo nestling morphology. Where cuckoos exploit multiple hosts, selection for mimicry drives genetic and phenotypic divergence corresponding to host preference, even in sympatry. Our work elucidates perhaps the most common, but poorly characterized, evolutionary process driving biological diversification.

2D signal estimation for sparse distributed target photon counting data.

In this study, we explore the utilization of penalized likelihood estimation for the analysis of sparse photon counting data obtained from distributed target lidar systems. Specifically, we adapt the Poisson Total Variation processing technique to cater to this application. By assuming a Poisson noise model for the photon count observations, our approach yields denoised estimates of backscatter photon flux and related parameters. This facilitates the processing of raw photon counting signals with exceptionally high temporal and range resolutions (demonstrated here to 50 Hz and 75 cm resolutions), including data acquired through time-correlated single photon counting, without significant sacrifice of resolution. Through examination involving both simulated and real-world 2D atmospheric data, our method consistently demonstrates superior accuracy in signal recovery compared to the conventional histogram-based approach commonly employed in distributed target lidar applications.

Exploring decision-making performance in young adults with mental health disorders: a comparative study using the Cambridge gambling task.

Decision-making deficits, assessed cognitively, are often associated with mental health symptoms, however, this relationship is not fully understood. This paper explores the relationship between mental health disorders and decision-making, using the Cambridge Gambling Task (CGT). Our study investigated how decision-making varied across 20 different mental health conditions compared to controls in a sample of 572 young adults from the Minneapolis and Chicago metropolitan areas, using a computerized laboratory-based task. Almost all mental health conditions were associated with at least mild (i.e. at least small effect size) impairment in all three studied parameters of the CGT (risk adjustment, quality of decision-making and overall proportion of bet). Notably, binge eating disorder had the largest cognitive impairment and gambling disorder had moderate impairment. Post-traumatic stress disorder (PTSD) was associated with impaired decision-making while obsessive-compulsive disorder (OCD) and depression showed moderate impairment. Additionally, half of the disorders assessed had moderate to large impairment in risk adjustment.These findings suggest that mental health conditions may have a more complex cognitive profile than previously thought, and a better understanding of these impairments may aid in risk assessment and targeted clinical interventions. This study underscores the need for further research to determine the causal pathways between mental health conditions and cognition, as well as to better understand the day-to-day impact of such deficits.

Unmasking Distorted Reflections: Exploring Body Image, Alcohol, and Drug Use in Nighttime Entertainment Districts.

Background: Violence within nighttime entertainment districts (NEDs) has been blamed on problematic masculinity and has predominantly been attributed to excessive alcohol intake and steroid use in men. In this report we conducted two studies to: (1) ascertain whether researchers could act as third-party raters of body weight and muscle mass in NED patrons; and (2) to examine the relationship between body self-image, inebriation, alcohol preloading behaviors and drug use in the NEDs. Methods: Study 1 employed an observational approach to establish inter-rater reliability for ratings of muscle mass and weight. In Study 2 data (n = 2,745) were collected through breathalyzing and questionnaires to examine individuals' self-image and drinking and drug-taking behaviors. Results: Participants' self-ratings of muscle and weight significantly differed from researchers' ratings, with males perceiving themselves as less muscular and females perceiving themselves as heavier. Perceived weight and muscle size did not relate to alcohol levels, but an interaction was found for female steroid users who perceived themselves as less muscular. Conclusions: Findings indicated a distortion in participants' perceived body image, with a desire for muscularity among both males and females. These results underscore the complex interplay between self-perception, societal ideals, and drug use in young NED patrons.

Multifunction fluorescence open source in vivo/in vitro imaging system (openIVIS).

The widespread availability and diversity of open-source microcontrollers paired with off-the-shelf electronics and 3D printed technology has led to the creation of a wide range of low-cost scientific instruments, including microscopes, spectrometers, sensors, data loggers, and other tools that can be used for research, education, and experimentation. These devices can be used to explore a wide range of scientific topics, from biology and chemistry to physics and engineering. In this study, we designed and built a multifunction fluorescent open source in vivo/in vitro imaging system (openIVIS) system that integrates a Raspberry Pi with commercial cameras and LEDs with 3D printed structures combined with an acrylic housing. Our openIVIS provides three excitation wavelengths of 460 nm, 520 nm, and 630 nm integrated with Python control software to enable fluorescent measurements across the full visible light spectrum. To demonstrate the potential applications of our system, we tested its performance against a diverse set of experiments including laboratory assays (measuring fluorescent dyes, using optical nanosensors, and DNA gel electrophoresis) to potentially fieldable applications (plant and mineral imaging). We also tested the potential use for a high school biology environment by imaging small animals and tracking their development over the course of ten days. Our system demonstrated its ability to measure a wide dynamic range fluorescent response from millimolar to picomolar concentrations in the same sample while measuring responses across visible wavelengths. These results demonstrate the power and flexibility of open-source hardware and software and how it can be integrated with customizable manufacturing to create low-cost scientific instruments with a wide range of applications. Our study provides a promising model for the development of low-cost instruments that can be used in both research and education.

Considerations for peer research and implications for mental health professionals: learning from research on food insecurity and severe mental illness.

WHAT IS KNOWN ON THE SUBJECT: Peer research methodologies and methods are increasingly used in research, particularly to benefit from lived experiences. The experiences of peer researchers with severe mental illness are less common, including the impact on them of conducting peer-led research. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE: This paper shares the experience of peer research and suggests in the context of food insecurity, that it is not well understood by some healthcare professionals. WHAT ARE THE IMPLICATIONS FOR PRACTICE: Implications include considerations around trauma-informed care and the need for screening for food insecurity in mental healthcare settings. Research implications include providing training for peer research and needing to consider longevity of peer researcher relationships. ABSTRACT: Introduction Food insecurity means that a person does not have access to sufficient nutritious food for normal growth and health. This can lead to health problems such as obesity, heart disease, diabetes and other long term chronic health conditions. People living with a severe mental illness are more likely to experience food insecurity than people without a severe mental illness. Aim The aim of this paper is to present a lived experience narrative of two peer researchers. Peer researchers conducted interviews with adults with severe mental illness from Northern England as part of a funded research project. These interviews discussed experiences of food insecurity and strategies to tackle it and were conducted between March and December 2022. Thesis The following paper does not discuss the results of the interviews themselves. Rather the narrative begins with an overview of peer research, before sharing the experiences of the two peer researchers in undertaking this project. Implications for Practice This includes healthcare professionals understanding food insecurity, what it is and what it is not, thinking about trauma-informed care, and screening for food insecurity. Peer research implications centre on adequate support and training, considerations to longevity of peer research relationships and reducing unnecessary research burden for peer researchers.

Food insecurity in adults with severe mental illness living in Northern England: A co-produced cross-sectional study.

AIM: This study aimed to explore food insecurity prevalence and experiences of adults with severe mental illness living in Northern England. METHODS: This mixed-methods cross-sectional study took place between March and October 2022. Participants were adults with self-reported severe mental illness living in Northern England. The survey included demographic, health, and financial questions. Food insecurity was measured using the US Department of Agriculture Adult Food Security measure. Quantitative data were analysed using descriptive statistics and binary logistic regression; and qualitative data using content analysis. RESULTS: In total, 135 participants completed the survey, with a mean age of 44.7 years (SD: 14.1, range: 18-75 years). Participants were predominantly male (53.3%), white (88%) and from Yorkshire (50.4%). The food insecurity prevalence was 50.4% (n = 68). There was statistical significance in food insecurity status by region (p = 0.001); impacts of severe mental illness on activities of daily living (p = 0.02); and the Covid pandemic on food access (p < 0.001). The North West had the highest prevalence of food insecurity (73.3%); followed by the Humber and North East regions (66.7%); and Yorkshire (33.8%). In multivariable binary logistic regression, severe mental illness' impact on daily living was the only predictive variable for food insecurity (odds ratio = 4.618, 95% confidence interval: 1.071-19.924, p = 0.04). CONCLUSION: The prevalence of food insecurity in this study is higher than is reported in similar studies (41%). Mental health practitioners should routinely assess and monitor food insecurity in people living with severe mental illness. Further research should focus on food insecurity interventions in this population.

Heat exposure as a cause of injury and illness in mine industry workers.

The objective of this study was to explore the association between ambient temperature and injuries and illnesses experienced by mine industry workers. Eleven years of de-identified data from a mine industry company in Australia was explored in regards to injuries and illnesses occurring due to outdoor exposure. Each case was filtered for reported symptoms, and meteorological data to match the location of the mine site and date reported were sourced. Of the 18 931 injuries and illnesses observed over the 11-year period, 151 cases of heat-related illness due to outdoor exposure were reported. Twenty-five conditions/symptoms of heat-illness were found, with the most prevalent being dehydration (n = 81), followed by heat rash (n = 40), dizziness (n = 24), and headache (n = 23). The mean number of symptoms reported by each worker was 2 ± 1. There was a positive correlation between ambient temperature and injuries/illnesses (r2 = 0.89, P < 0.001), where, as temperature increased so did the number of reported heat-related illnesses. Underreporting of heat-related illness and injury in the mining industry is likely, which is a risk to the health and wellbeing of employees. Workers require industry specific training about the severity of heat stress and the associated prevention strategies.

Preoperative patient factors that predict achieving the minimal clinically important difference following arthroscopic treatment of snapping scapula syndrome.

BACKGROUND: The aim of this study was to define the minimal clinically important difference (MCID) values for patient-reported outcomes (PROs) after arthroscopic treatment of snapping scapula syndrome (SSS) using a distribution-based method, and to identify demographic, clinical, and intraoperative factors significantly associated with the achievement of MCID. It was hypothesized that subjective satisfaction scores after the procedure would be strongly associated with the achievement of MCID thresholds for the PROs and that pain, preoperative response to injection, and a scapulectomy in addition to bursal resection would be predictive of clinically relevant improvement. METHODS: Patients who underwent arthroscopic treatment of SSS between October 2005 and September 2020 with a minimum of 2-year short-term postoperative follow-up were enrolled in this retrospective single-center study. The MCID was calculated using a distribution-based approach for the following PROs: 12-Item Short Form Health Survey (SF-12), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Quick Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH), Single Assessment Numeric Evaluation (SANE), and visual analog scale (VAS) pain "today" and "at worst." The association between achievement of the MCID and postoperative subjective satisfaction was investigated, and factors associated with achievement of MCID were determined using bivariate analysis. RESULTS: Of a total of 190 patients assessed for eligibility, 77 patients (38.1 ± 14.3 years; 36 females) were included. Within the study population, statistically significant improvements in postoperative SF-12 physical component summary (PCS) (P < .001) and mental component summary (MCS) (P < 0.034), ASES (P < .001), QuickDASH (P < .001), SANE (P < .001), and VAS pain (P < .001) scores were observed at the minimum 2-year follow-up. The calculated MCID threshold values based on the study population were 5.0 for SF-12 PCS, 5.8 for SF-12 MCS, 11.3 for ASES, -10.5 for QuickDASH, 14.7 for SANE, 1.5 for VAS pain, and 1.7 for VAS pain at worst. Reaching the MCID was strongly associated with postoperative satisfaction (rated on a scale of 1-10). Across the PROs, younger age, favorable preoperative response to injection, partial scapuloplasty or scapulectomy, no prior surgery, and pain and function at baseline were significantly associated with attaining MCID. CONCLUSIONS: Patients who underwent arthroscopic treatment for SSS experienced clinically significant improvements in functional scores, pain, and quality of life. This study demonstrated predictive roles for certain patient-specific factors and diagnostic variables for achieving MCID in PROs, which may help surgeons preoperatively assess the probability of success and manage patient expectations.

Improved Glycemic Outcomes With Diabetes Technology Use Independent of Socioeconomic Status in Youth With Type 1 Diabetes.

OBJECTIVE: Technology use in type 1 diabetes (T1D) is impacted by socioeconomic status (SES). This analysis explored relationships between SES, glycemic outcomes, and technology use. RESEARCH DESIGN AND METHODS: A cross-sectional analysis of HbA1c data from 2,822 Australian youth with T1D was undertaken. Residential postcodes were used to assign SES based on the Index of Relative Socio-Economic Disadvantage (IRSD). Linear regression models were used to evaluate associations among IRSD quintile, HbA1c, and management regimen. RESULTS: Insulin pump therapy, continuous glucose monitoring, and their concurrent use were associated with lower mean HbA1c across all IRSD quintiles (P < 0.001). There was no interaction between technology use and IRSD quintile on HbA1c (P = 0.624), reflecting a similar association of lower HbA1c with technology use across all IRSD quintiles. CONCLUSIONS: Technology use was associated with lower HbA1c across all socioeconomic backgrounds. Socioeconomic disadvantage does not preclude glycemic benefits of diabetes technologies, highlighting the need to remove barriers to technology access.

Rare SH2B3 coding variants in lupus patients impair B cell tolerance and predispose to autoimmunity.

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with a clear genetic component. While most SLE patients carry rare gene variants in lupus risk genes, little is known about their contribution to disease pathogenesis. Amongst them, SH2B3-a negative regulator of cytokine and growth factor receptor signaling-harbors rare coding variants in over 5% of SLE patients. Here, we show that unlike the variant found exclusively in healthy controls, SH2B3 rare variants found in lupus patients are predominantly hypomorphic alleles, failing to suppress IFNGR signaling via JAK2-STAT1. The generation of two mouse lines carrying patients' variants revealed that SH2B3 is important in limiting the number of immature and transitional B cells. Furthermore, hypomorphic SH2B3 was shown to impair the negative selection of immature/transitional self-reactive B cells and accelerate autoimmunity in sensitized mice, at least in part due to increased IL-4R signaling and BAFF-R expression. This work identifies a previously unappreciated role for SH2B3 in human B cell tolerance and lupus risk.

Mixed-Method Precooling Enhances Self-Paced 20-km Cycling Time-Trial Performance When Apparent Temperature Is >46 °C but May Not Be a Priority in <46 °C.

PURPOSE: Precooling (PreC) may only benefit performance when thermal strain experienced by an individual is sufficiently high. We explored the effect of mixed-method PreC on 20-km cycling time-trial (CTT) performance under 3 different apparent temperatures (AT). METHODS: On separate days, 12 trained or highly trained male cyclists/triathletes completed six 20-km CTTs in 3 different ATs: hot-dry (35 °C AT), moderately hot-humid (40 °C AT), and hot-humid (46 °C AT). All trials were preceded by 30 minutes of mixed-method PreC or no PreC (control [CON]). RESULTS: Faster 2.5-km-split completion times occurred in PreC compared with CON in 46 °C AT (P = .02), but not in 40 °C AT (P = .62) or 35 °C AT (P = .57). PreC did not affect rectal and body temperature during the 20-km CTT. Skin temperature was lower throughout the CTT in PreC compared with CON in 46 °C AT (P = .01), but not in 40 °C AT (P = 1.00) and 35 °C AT (P = 1.00). Heart rate had a greater rate of increase during the CTT for PreC compared with CON in 46 °C AT (P = .01), but not in 40 °C AT (P = .57) and 35 °C AT (P = 1.00). Ratings of perceived exertion (P < .001) and thermal comfort (P = .04) were lower for PreC compared with CON in 46 °C AT only, while thermal sensation was not different between PreC and CON. CONCLUSION: Mixed-method PreC should be applied prior to 20-km CTTs conducted in hot-humid conditions (≥46 °C AT). Alternatively, mixed-method PreC may be a priority in moderately hot-humid (∼40 °C AT) conditions but should not be in hot-dry (∼35 °C AT) conditions for 20-km CTT.

A seasonal comparison of a 14-day swing on cognitive function and psycho-physiological responses in mine service workers.

This study assessed the effect of season on cognitive function and psycho-physiological responses during a 14-day swing in mine-service workers. Cognitive function, thermal sensation and comfort, rating of perceived exertion, fatigue, hydration, core temperature and heart rate were assessed throughout a shift, on three separate days over a swing. Working memory and processing efficiency did not differ between seasons (p > 0.05), however counting and recall latencies improved throughout the swing (p < 0.05). Participants reported greater fatigue post-shift compared to pre-shift (p < 0.05). Thermal sensation, thermal comfort, and hydration were significantly elevated in summer compared to winter (p < 0.05). Specifically, workers were significantly/minimally dehydrated in summer/winter (urinary specific gravity = 1.025 ± 0.007/1.018 ± 0.007). Although cognitive function and thermal strain were not impaired in summer compared to winter, it is essential to reinforce worker's knowledge regarding hydration requirements. Additional education and/or incorporating scheduled rest breaks for hydration should be considered to ensure the health and safety of mine workers.