Maintaining an optimal indoor thermal environment is crucial for enhancing the welfare and productivity of livestock in intensive breeding farms. This paper investigated the application of a combined geothermal heat pump with a precision air supply (GHP-PAS) system for cooling dairy cows on a dairy farm. The effectiveness of the GHP-PAS system in mitigating heat stress in lactating dairy cattle, along with its energy performance and local cooling efficiency in the free stalls were evaluated. A total of 140 multiparous lactating Holstein cows was tested in two groups. One group was housed in a barn equipped with a GHP-PAS system (GP barn, n = 70), and the other was housed in a barn with a conventional fan-sprinkling system (FS barn, n = 70). Results showed that the ambient temperature of both GP and FS barns were lower than that outside the barn (P < 0.05), with no significant difference between the GP and FS barns (P > 0.05). Compared to cows in the FS barn, those in the GP barn exhibited lower skin temperature, rectal temperature, and respiratory rate (P < 0.05). The mean temperature difference between outflow and inflow water was 2.56 °C of the GHP unit. The average energy efficiency ratios (EER) of the GHP unit and the GHP-PAS system were 5.03 and 2.92, respectively. The daily average electricity consumption was 20.4 ± 1.0 kWh. The field test results indicated that the airflow from a single nozzle of the GHP-PAS system effectively covered a stall space with an average width of 1.84 m at a cow reclining height of 0.5 m, with an average air velocity of 1 m/s. The per-cow hourly electricity consumption for cooling was 2.04 kWh for the GHP-PAS system and 0.36 kWh for the FS system, highlighting that the GHP-PAS system is approximately 5.6 times more energy-intensive than the FS system. In conclusion, the GHP-PAS system showed the potential for alleviating heat stress in dairy cows. Further research is needed to enhance the energy efficiency and cooling effectiveness of the current GHP-PAS system.

Climate warming and frequent incidents of extreme high temperatures are serious global concerns. Heat stress induced by high temperature has many adverse effects on animal physiology, especially in aquatic poikilotherms. Chinese mitten crab (Eriocheir sinensis) is sensitive to high temperatures, this study evaluated the harmful effects of heat stress on the neurotoxicity, intestinal health, microbial diversity, and metabolite profiles. The results showed that heat stress caused histopathological damages and altered the ultrastructure of lesions in the cranial ganglia. Heat stress significantly upregulated the mRNA expression of apoptosis-related genes, and significantly altered the expression of neurotransmitter receptors. In addition, heat stress induced significant intestinal damages that mainly manifested as a significant increase in the activity of diamine oxidase in the serum and contents of histamine in the intestine. The diversity and abundance of intestinal microbiota altered abnormally in E. sinensis exposed to heat stress, and the bacteria that exhibited significant variations in abundance were closely related to the production of neurotransmitters and neuromodulators. Heat stress caused significant changes in the intestinal metabolite profiles, which mainly involved the amino acid and lipid metabolism pathways. Analysis of the correlation showed that the abnormal changes in metabolites were closely related to differences in the abundance of intestinal microbiota. Therefore, this study showed that heat stress could cause neurophysiological toxic effects, which may be related to intestinal ecological imbalance.

The traditional overwintering process of sea cucumbers (Apostichopus japonicus) requires burning a large amount of coal to raise the water temperature. It is useful but costly and not environmentally friendly. Bacillus is proposed as a cheap and green alternative. Therefore, this study intended to achieve cleaner production of A. japonicus by adding Bacillus to their diet at low temperature (7 °C) to achieve the production efficiency of sea cucumbers cultured by heating water to 11 °C. Here, we found that number of crawl steps, relative food intake, relative fecal outputs, amylase and proteinase activities, body weight and weight gain rate significantly reduced, and intestinal morphology and intestinal microbiota were also worse in sea cucumbers at low temperature (7 °C), compared with the sea cucumbers cultured at 11 °C. This suggests that low temperature negatively affect the behaviors, intestinal health, and growth of A. japonicus. However, the adverse effects on the behavioral capacities (such as number of crawl steps, relative food intake and relative fecal outputs), intestinal health (such as digestive enzyme activities and intestinal morphology), and growth (such as body weight and weight gain rate) of sea cucumbers under low temperature conditions were compensated after adding dietary Bacillus (Bacillus methylotrophicus and Bacillus amyloliquefaciens) at 10 CFU/g. These traits reached the level of those in sea cucumbers cultured at 11 °C with no significant difference, and were significantly different from those cultured at 7 °C without adding Bacillus. Importantly, the intestinal microbiota structure of sea cucumbers was greatly improved after the addition of dietary Bacillus, reducing the proportion of Proteobacteria and the consequent probability of diseases. In conclusion, the results suggest that dietary supplementation with Bacillus can reverse the adverse effects caused by 4 °C of temperature difference (between 7 °C and 11 °C) on sea cucumbers. Therefore, we recommend that aquaculture farmers use a combination of burning limited coal to increase water temperature to 7 °C and feeding Bacillus to improve the production efficiency of A. japonicus in winter.

Questionnaires exploring tourists' perceptions of ideal climatic conditions are argued to be a more suitable data source for the development of tourism climate indices than the utilization and integration of expert opinion and pre-established thresholds. This assumes that those tourist respondents can accurately quantify meteorological conditions at a given point in time, and effectively discriminate between meteorological thresholds of suitable and unsuitable conditions. For variables such as rainfall and sunshine hours, this assumption is fairly reasonable. However, where tourists' perceptions, captured through questionnaire responses, are used to set thresholds for air temperature and thermal comfort, it is important to determine whether those perceptions are valid. Previous studies contest this, indicating considerable differences in perceptions of heat thresholds based on terminology, nationality, destination, and time of the year. In this study, a benchmarking exercise is performed comparing perceived temperatures and thermal comfort to measured values, through questionnaires administered to 984 adults in South Africa. Findings indicated that while 19.9% of responses are within 1 °C of measured temperatures, up to 12.8% of respondents perceive temperatures as being at least 6 °C higher or lower than the measured values. There are no clear geographic or demographic variables that effectively discriminate between accurate and inaccurate responses. When asked to classify their level of thermal comfort, as opposed to quantifying temperatures, results aligned more closely with measures and classifications of effective temperature. Based on these results, we argue that greater caution should be applied when using temperature thresholds derived from questionnaire data in developing and calibrating any biometeorological indices, and focus instead should be placed on catergorized levels of self-reported thermal comfort in environments where raw meteorological conditions are measured.

Laparoscopic cholecystectomy is a common procedure for gallbladder diseases, but many patients experience shoulder pain due to pneumoperitoneum. This study investigates the comparative effectiveness of warm carbon dioxide gas insufflation versus local heat application in reducing shoulder pain after laparoscopic cholecystectomy. We also examined changes in body temperature during surgery and postoperative shivering in the intervention and control groups.

The creation of any model is complex requiring vast amounts of data, typically gathered over a series of experiments. Specifically the temperature humidity index (THI) and heat load index (HLI) are used as management tools to implement mitigation strategies during hot climatic conditions. Exposure of the testes to hot climatic conditions has a negative impact on spermatogenesis in the bull, and other species. Despite the bull having effective scrotal thermoregulatory ability, these mechanisms can breakdown when the bull is under heat stressed causing scrotal temperature to increase. The ability to understand the effect climatic conditions have on scrotal temperature could be a valuable tool for producers. Six Wagyu bulls were exposed to series of heat treatments, acute and chronic with thermoneutral periods in between, in climate controlled rooms. Abdominal and scrotal temperature were continuously recorded via surgically implanted data loggers. Ambient temperature (AT) and relative humidity (RH) throughout the same periods were monitored. An information theoretic approach was used to analyse the data. Data were split into three groups, one for each of the ambient conditions of acute, chronic and thermoneutral. A global model for each of these groups was constructed using generalised additive models and included all parameters of interest; abdominal temperature, AT, RH and THI. Additional candidate models consisting of subsets of these global models were run for each acute, chronic and thermoneutral. Models were statistically compared and multimodel inferencing used to determine the effect these parameters had on scrotal temperature. The best model for acute included abdominal temperature, RH and an autoregressive factor (AR(1)) whilst the best model for both chronic and thermoneutral included just abdominal temperature and AR(1). Adding abdominal temperature to the model for the acute and chronic treatments improved the model strength with an increase in abdominal temperature increasing scrotal temperature. In contrast, the addition of abdominal temperature to the thermoneutral models did not consistently improve their strength. Despite a small sample size, the data indicates that scrotal temperature can be modelled. The addition of future observations to these models will continue to strengthen models, improving their usability.

The presence of nestlings influences the microclimate inside avian nesting cavities. We explored the relationship between temperature and relative humidity and the abundance of ectoparasites and gas concentrations in blue tit nest boxes during the nestling period by comparing two years with differing climatic conditions. In the second year, we also manipulated the temperature and humidity inside the nest boxes. The average temperature in nest boxes was colder during 2016 than 2017; in the latter, even warmer conditions were attained due to the experimental manipulation of temperature. Carbon dioxide (CO) concentration in the forest air was slightly lower in 2016 than 2017. However, in both years, the CO concentration of nest box air was higher than that of forest air, with 2017 showing a greater difference. Differences in brood size, larger in 2016, did not explain the difference in CO concentration. However, CO concentration was higher in nestboxes in the warmer year implying that at higher temperatures, organic matter decomposition likely accelerates, releasing more CO into the atmosphere. By contrast, CH concentration in nest-box air, which was similar in both years, was lower than that in forest air, particularly in the wettest and coldest year. Different relationships were found between the abundance of different ectoparasites and the temperature, relative humidity, and gas concentration measured at different days of nestling age. For example, a positive association is observed between flea larval abundance and temperature at nestling day 8, but a negative one is observed for mites under the same microclimate conditions. Moreover, a negative relationship was observed between the abundance of mites, midges, and blackflies and CH concentration at different nestling ages. These results suggest that changes in climatic conditions can also affect the concentrations of CH and CO inside and outside nest boxes, which in turn differentially affect ectoparasite abundance.

Critical thermal maximum (CT) is the most widely used method for quantifying acute upper thermal limits in ectotherms. CT protocol exposes animals to a consistent rate of environmental warming until they lose motor function. CT has been used to assess intraspecific variation among life stages, populations, or as a function of body size, often with the assumption that it is a durable and heritable trait at the individual level. The existence of within-individual repeatability of CT has been used to infer the potential for thermal adaptation via the positive correlation between the repeatability of a trait and its heritability. However, for how widely used CT has become, surprisingly few studies have quantified within-individual repeatability in aquatic ectotherms, and none have assessed repeatability across contexts. We examined the cross-context repeatability of CT in two freshwater ectotherms (one decapod crustacean and one teleost fish): rusty crayfish Faxonius rusticus (n = 31) and pumpkinseed Lepomis gibbosus (n = 38). Individual repeatability was measured on a weekly basis across multiple trials (n = 5 pumpkinseed CT measurements, n = 7 rusty crayfish) that varied in acclimation temperature, oxygen saturation, and salinity. CT was most strongly influenced by acclimation temperature. Repeatability varied based on the statistical approach and between the two species. Pumpkinseed repeatability across contexts was moderate (ca. 0.4), similar to previous reports on within-context CT repeatability studies in fishes. In rusty crayfish, repeatability was much lower (ca. 0.16). This suggests CT repeatability may be both taxon- and context-dependent, thus further investigation into repeatability is needed across species for this important and widely used trait.

This study examined the impact of curcumin nanomicelles (CNM) supplementation on transitioning ewes and their offspring. Thirty-two crossbred pregnant ewes [Ile-de-France × (Dalagh × Romanov)], confirmed to carry twins, were randomly assigned to a control group (CTRL) or a treatment group receiving 40 mg of CNM per ewe per day. Supplementation began before and continued after delivery. We assessed various parameters, including growth performance, metabolic health, inflammatory markers, hematological profiles, immunoglobulin levels, antioxidant status, and greenhouse gas emissions. CNM supplementation improved growth in both ewes and lambs, consistent with curcumin's known metabolic effects. Significant reductions in inflammatory markers were observed in both ewes and lambs, with decreased neutrophil-to-lymphocyte ratios indicating reduced systemic inflammation. Increased levels of IgG and IgA in both ewes and lambs suggested improved immune competence. Antioxidant biomarkers indicated better management of oxidative stress, with some benefits extended to offspring. CNM had varying effects on methanogen populations and nitrous oxide emissions. It significantly reduced methanogen numbers postpartum, but had no significant effect pre-partum. A slight increase in N2O emissions was observed before delivery, but was not sustained after delivery. These results underscore the complex interactions of metabolic, immunological, and environmental factors influenced by CNM supplementation during the transition period. More research is needed to refine supplementation strategies, evaluate long-term effects, and explore ways to mitigate increased greenhouse gas emissions while preserving health benefits.

Environmental temperature impacts the physiological processes of reptiles, determines their hours of activity per day, and may constrain their ability to meet critical ecological requirements. When environmental temperatures reach freezing, a few lizard species exhibit two mechanisms (supercooling and freezing tolerance) to survive freezing, and these two processes depend on cryoprotective molecules, such as glucose. Organisms produce high glucose concentrations to reach lower than normal crystallisation points, and this blood glucose concentration can double after freezing. The viviparous lizard Barisia imbricata lives along a wide elevational gradient (2100-4000 m) at tropical latitudes in temperate and subtropical climates. Populations at extremely high elevations experience environmental temperatures at or below 0 °C. We measured blood glucose concentrations in the lizard B. imbricata in different seasons and compared the values between seasons and between two populations occurring at the elevations of 2200 and 3700 m. In addition, we froze lizards from the two populations and measured their blood glucose concentrations before and after freezing. We did not observe any differences in blood glucose concentrations between different seasons or the two populations. In addition, all lizards survived freezing; their mean crystallisation point was -4.13 °C. Blood glucose concentration in the lizards increased after exposure to freezing temperatures during autumn and winter. Our results indicate that B. imbricata tolerates experimental freezing even in individuals not naturally exposed to subzero temperatures (i.e. populations at 2200 m). Elevated blood glucose concentrations (present year-round) may help B. imbricata individuals survive at low temperatures.

Animals can respond differently to shifting thermal variability versus thermal averages, both of which are changing due to climate warming. How these thermal variables affect parental care behaviors can reveal the ability of parents to modify their behaviors to meet the competing demands of their offspring's thermal needs and self-maintenance, which becomes critical in suboptimal thermal conditions. Further, the time frame used to examine the interplay between temperature and behavioral shifts (e.g., seasonal patterns in care vs. drivers of individual care decisions) can provide different information about the plasticity of parental care behavior. We investigated the relationship between thermal means, thermal variability, and incubation behaviors across multiple timescales in Scaled Quail and Northern Bobwhite. Both species decreased off-bout length during periods of high thermal variability, a novel finding among studies of avian parental behavior. Further relationships between thermal endpoints (mean vs. variation) and behavior differed depending on the temporal scale. For instance, total daily time spent off the nest was not influenced by daily average temperature, yet individual off-bout duration increased with increasing average temperature in the 2 h prior to the off-bout. These results provide evidence that thermal-behavioral relationships differ across scales and likely represent a bird's ability to modify their incubation strategy to rapidly respond to the immediate thermal environment (altering individual off-bout length based on temperature) to meet self-maintenance needs while resulting in a similar outcome for their nest (total daily off-bout time). However, longer off-bout durations during high temperature events can come with reproductive costs, sometimes resulting in acute offspring mortality when eggs or chicks experience lethal temperatures.

This study aimed to evaluate the effects of different cold acclimation strategies on exercise performance in male mice exposed to low-temperature environments.

This study investigated the single and combined effects of environmental heat stress and physical exercise on executive function (EF) performance, prefrontal cortex oxygenation, thermoregulatory responses and subjective perceptions. Sixteen subjects participated in four experimental sessions: two under moderate environmental conditions (23 °C), with and without physical exercise (R23, E23), and two under hot environmental conditions (35 °C), with and without physical exercise (R35, E35). In each session, participants completed EF tasks before and after 1 h of passive rest or 45 min of moderate-intensity cycling followed by 15 min of rest. We used Δresponse time (ΔRT) and Δaccuracy (ΔACC) of EF tasks to demonstrate changes from pre to post experiment. Additionally, changes in cerebral oxygenation during EF tasks were illustrated using the Δoxygenation difference. Heat stress alone increased core temperature (T), mean skin temperature (T), heart rate (HR), thermal sensation (TS), and rating of perceived exertion (RPE). Exercise in a hot environment further increased physiological indicators and RPE, but TS exhibited a different pattern, with lower TS in R35 compared to E35 during the second battery of executive function tests. Moreover, heat stress alone increased ΔRT for the More-Odd Shifting task and the Stroop task under incongruent conditions, while decreasing the Δoxygenation difference during the More-Odd Shifting task. ΔRT for the 2-back, More-Odd Shifting and Stroop tasks under incongruent conditions were lower in the E35 trial than in the R35 trial, whereas the Δoxygenation difference was higher in the E35 trial compared to the R35 trial. These findings indicate that environmental heat stress alone increases T and T, alters TS, and impairs EF performance by decreasing prefrontal cortex oxygenation. A 45-min moderate-intensity exercise combined with environmental heat stress enhances the increases in body temperatures but mitigates the detrimental effects of heat stress alone on EF performance by increasing prefrontal cortex oxygenation.

Small birds in winter can mitigate energetic shortfalls via increases in foraging and/or via controlled reductions in metabolic rate and body temperature (torpor). The ability to both increase foraging and use torpor during the day could have profound implications for an individual's daily energy budget and overwinter survival. Trade-offs between foraging efficiency and daytime torpor use may exist but have not been explicitly investigated. Here, we investigated the presence of within- and among-individual correlations between daytime body temperature (T a proxy for torpor use) and foraging in overwintering black-capped chickadees (Poecile atricapillus). Using temperature-sensing passive integrated transponder tags, we measured daytime T and foraging in 20 free-living chickadees over 49 days in a single winter (January-February). Chickadees generally exhibited T around normothermic levels with an average T during visits to the feeder of 41.7 °C, though T ranged between 25.0 and 44.9 °C. Chickadees exhibited moderately lower daytime T, shorter time intervals between successive feeder visits (IVI), and increased feeder visits as ambient temperature decreased. However, within individuals there was only evidence of a weak positive correlation between visit T and IVI, and no correlation between daily feeder visits and daily mean visit T We found that visit T, daily mean visit T and daily feeder visits were repeatable, while IVI was not. Sex did not explain a significant amount of variation in total daily feeder visits or daytime T, nor was there evidence of among-individual correlations between daily mean visit T and daily feeder visits. Our results suggests that chickadees may independently regulate foraging and diurnal T. Overall, our study provides insights into how small birds in winter can use multiple strategies to overcome energetic challenges. Future studies investigating diurnal torpor and its integration with other strategies are needed to further elucidate how small birds survive harsh winter conditions.

Obesity, recognized as a metabolic disease and a global epidemic, calls for novel pharmacological interventions. Menthol, an organic compound, has shown promise in increasing energy expenditure and has been proposed as a potential anti-obesity drug. While preclinical studies have demonstrated menthol's preventive effect on body mass gain, none have investigated its efficacy in treating obesity. In this study, we evaluated the therapeutic potential of menthol in obesity treatment. Obesity was induced in rats through a hypercaloric diet. Obese rats were subjected to intermittent topical treatment with 5% menthol, resulting in sustained hyperthermia indicative of increased thermogenesis and energy expenditure. Additionally, menthol led to a reduction in the area of white adipocytes as a result of weight loss in obese rats. Our findings suggest that menthol has the potential to enhance metabolism and may serve as a viable treatment option for obesity. These results highlight the physiological significance of menthol in modulating metabolic processes and its potential role in combating obesity-related metabolic disorders.

Ectotherms are considered more susceptible to global warming. Variations in ambient temperature are especially alarming as the majority of animals are ectothermic, with temperature seen as a crucial determinant of their ecology, biogeography, behaviour, and physiology. Ectotherms, which depend on external ambient temperatures to regulate their body temperature, exhibit various physiological and metabolic responses to variations in temperature. These responses are essential for comprehending how these species will acclimatise to changing water temperatures and the consequent alterations in oxygen availability. This study assessed the acclimation ability, temperature tolerance, and metabolic rate of narrow-clawed crayfish (Pontastacus leptodactylus) to elucidate the crayfish's responses to potential climate change. Our study showed that the narrowed clawed crayfish is a species that exhibits high thermal tolerance, with an extensive dynamic (1114 °C), static thermal polygon area (966 °C), resistance zone of 103 °C and the ability to withstand extreme temperatures (CT-CT: 1.60-36.8 °C). The acclimation temperature has minimal impact on the thermal tolerance of the crayfish (P < 0.01). The optimal temperature range for SMR of Pontastacus leptodactylus is 20-25 °C, within which a decline in standard metabolic rate (SMR) occurs as temperature rises.

Women may be challenged to maintain thermoregulation due to hormonal changes associated with the menstrual cycle. The purpose of this study was to assess the effect of the menstrual cycle phase on core temperature, hydration status, and perceived exertion while exercising under uncompensable heat gain. Eleven eumenorrheic women (24.4 ± 1.1 yrs, 65.7 ± 2.4 kg, 22.7 ± 1.5% body fat) walked for two 180-min trials in a heat chamber (35 °C and 30% relative humidity) during early-follicular (EF) and mid-luteal (ML) phases. Subjects completed three intervals of 50 min of exercise at 50% VOmax. Physiological strain index (PSI), core temperature (T), perceived heat (PH), and rating of perceived exertion (RPE) were measured throughout both trials. Nude body weight (NBW) and blood samples were collected pre- and post-trial. Blood samples were analyzed for hematocrit (Hct), hemoglobin (Hb), serum estrogen, progesterone, and aldosterone. NBW showed a main effect of time (p = 0.002, η = 0.62). Aldosterone showed main effect of time (p = 0.004, η = 0.59) and phase (p = 0.014, η = 0.47), peaking post exercise in both EF and ML (527.6.1 ± 89.0 pg·mL vs 827.4 ± 129.5 pg mL respectively, p = 0.014). Estradiol and progesterone showed main effects of phase (p = 0.007, η = 0.53; p = 0.045, η = 0.30) but not time (p = 0.68, p = 0.32). T showed main effect of time (p < 0.001, η = 0.89) and phase, peaking at 170 min (EF: 37.8 ± 0.1 °C vs. ML: 38.0 ± 0.1 °C, p = 0.032, η = 0.38). Main effect of time was seen for PSI (p = 0.002, η = 0.88), PH (p = 0.004, η = 0.66), and RPE (p = 0.026, η = 0.80). Sweat rate, Hct, Hb, and percent dehydration were not different between the phases. In conclusion, subjects demonstrated elevated Tc and basal aldosterone in ML corresponding with elevations in estrogen and progesterone. Aldosterone significantly increased following exercise in the heat but remained elevated in ML. These results indicate that elevated Tc during ML is maintained during exercise in the heat despite similar perceived heat and effort between phases.

Estimating animal behaviour during heat stress (HS) is particularly insightful to monitor animal welfare but also to better understand how animals thermoregulate. The present study is a proof of concept combining computer vision to monitor animal behaviour, continuous monitoring of subcutaneous temperature and recording of ambient temperature, with the aim to study the link between behaviour and animal body temperature during HS. A total of 22 pigs were video-monitored from 8:00 to 18.00 under two contrasted conditions: HS corresponding to the tropical climate (between 20.3 °C and 27.9 °C) and Thermoneutral (TN) consisting of an indoor temperature-controlled room at 22 °C. Animal temperature (T) and ambient temperature were monitored continuously using temperature loggers. Pig postures estimated by a neural network show that animal in HS spend more time lying laterally and less time lying sternally than in TN. Moreover, in HS, the length of the lateral sequences increased with the outdoor ambient temperature. The ability of an animal to dissipate heat while lying laterally was quantified through a Heat Dissipation Coefficient (HDC), combining T and lateral lying sequence duration, and showed great individual variation. A Heat Discomfort Index (HDI) was also determined to quantify the difference in time spent lying laterally between HS and TN and could be useful as a proxy to quantify animal welfare reduction due to HS. This study demonstrates that combining image analysis to monitor animal behaviour and physiological data is an efficient tool to derive quantitative criterion to characterize animal welfare and traits related to heat tolerance.

The current study investigated if skin temperature (Tsk) measurement through infrared thermography could reflect the accumulation of training load during the preparatory period of a professional volleyball team. Sixteen athletes (20.1 ± 3.1 years, 88.1 ± 6.1 kg, 193 ± 0.1 cm e 13.3 ± 2.3 % body fat) were assessed over two weeks of the preparatory period (5 training days in each week) for the second division of the Brazilian Men's Volleyball Super League. After one week of familiarization with the study procedures, Tsk was measured in eight regions (anterior and posterior areas of arm, shoulder, thigh, and leg) on the first and last training days of each week, along with perceived recovery status (PRS) were measured on the first and last training days of each week. Training load for each session and total weekly training load (TWTL) were calculated using the session rating of perceived exertion (SRPE) method. Three days in the first week and four days in the second week had higher training loads (χ = 89.1, p < 0.001), as indicated by a significant reduction in recovery perception at the end of each week (F = 52.3, p < 0.001). Among the eight regions examined, five showed a decrease in Tsk after two rest days (weekend), while two regions exhibited an increase in Tsk at the end of the following training week (p < 0.05). Out of 44 associations examined between Tsk, PRS, and TWTL, only the associations between delta PRS and delta mean Tsk of the anterior and posterior leg were significant (β = -0.20, p < 0.045 for both). In conclusion, the data suggest that Tsk may be altered during the pre-competitive period of professional volleyball players; however, it does not appear to be associated with PRS and training load as assessed by the SRPE method.

Inhalation lung injury is an acute pulmonary impairment resulting from inhalation of hot air and/or toxic gases. However, the molecular mechanisms involved in hot air-induced heat stress (HS) response of alveolar epithelial cells are not fully understood. In this study, employing a cell heat loading device, we found that HS at 50 °C resulted in significant ferroptosis and injury of human alveolar epithelial cells (BEAS-2B cells), supported by increased lipid peroxidation, reactive oxygen species (ROS), and decreased ferritin heavy chain 1 (FTH1), glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11). Ferrostatin-1 (Fer-1), a targeted inhibitor of ferroptosis, could suppress HS-induced ferroptosis and injury of BEAS-2B cells. Moreover, HS activated extracellular signal-regulated kinase 1/2 (ERK1/2) in BEAS-2B cells. Nevertheless, blockage of ERK1/2 activation by U0126, an inhibitor of ERK1/2 phosphorylation, repressed HS-induced ferroptosis and injury of BEAS-2B cells. Taken together, this study demonstrates that HS injures alveolar epithelial cells through ERK1/2 signaling-mediated ferroptosis, which provides a novel potential strategy for the treatment of HS-induced inhalation lung injury.

As opportunistic generalists occupying a range of ecological niches, chacma baboons (Papio ursinus) are considered a highly flexible species of relatively low conservation priority. Underlying their ecological flexibility is a repertoire of behavioral strategies observed in response to ecological stressors. Although these strategies are relatively well-documented, we know very little about how they impact upon an individual's thermal and energetic physiology, which can influence population-level reproductive potential in the face of climatic warming. Here, we used Niche Mapper™ to construct a biophysical model that integrates morphometric, autonomic, and behavioral inputs to predict the core body temperature of chacma baboons in response to varied microclimate conditions. The predictive integrity of the model was confirmed by comparing model outputs with the core body temperature of a free-living chacma baboon equipped with an intra-abdominal temperature-sensitive data logger. When behavioral thermoregulation was incorporated, our model predicted body temperature within 1.5 °C of the observed temperature for 94% of hours. Of the tested behavioral thermoregulatory responses, shade-seeking provided the greatest thermal benefit, reducing predicted core body temperature by an average of 0.9 °C during daytime hours. Evaporative heat-dissipation strategies (sweating or swimming) were also highly effective in circumventing hyperthermia in our modeled individual, with an average body temperature reduction of 0.6 °C. Our findings underscore the critical importance of behavioral thermoregulatory strategies coupled with access to essential microhabitat features, water and shade, to achieve homeothermy in a warming climate.