Search Results (107)

A warm-up is a critical procedure in sports science for enhancing muscular performance and optimizing subsequent athletic activities. However, the physiological and athletic performance effects of a warm-up are often transient, diminishing rapidly during the period of inactivity after the warm-up, which is known as the warm-up transition phase. In this study, a multi-functional thermoregulation wearable composite film of graphene–MXene–bacterial cellulose/polyethylene glycol (G-M-BC/PEG) was developed by integrating MXene (a two-dimensional material with good photothermal conversion performance) and graphene into a bacterial cellulose aerogel framework, subsequently impregnated with polyethylene glycol (PEG-2000). The film showed stable structure, efficient solar photothermal conversion and storage (SPCS), and improved mechanical properties. Under 1 sun irradiation, the optimized G-M-BC/PEG wearable film showed excellent SPCS performance, sustaining a temperature plateau of 38–40 °C for 10 min after the xenon lamp was switched off under 1 sun irradiation, with a leakage rate of only 5.32% after five cycles. By constructing a biomimetic sports human body model, the composite aerogel was shown to significantly elevate muscle surface temperature and effectively mitigate heat loss during the transition phase. In the warm-up effectiveness and sports performance tests, the wearable film improved 200 m sprint performance by 0.8% ± 0.4% (p = 0.039). It also maintained subjective thermal sensation during the warm-up transition phase, with no significant decline at 5 or 10 min after the warm-up and a significant decrease only at 15 min (p = 0.02), while thermal comfort remained stable, suggesting improved neuromuscular readiness. This research provided a novel strategy for the fabrication of advanced aerogel-based wearable devices aimed at precision thermal management and athletic performance optimization. Full article

While persistent calyces exhibit considerable functional diversity, this has not been fully substantiated by experiments, especially concerning their thermoregulatory function. This study investigates the thermoregulatory function of persistent calyx in winter-flowering Brandisia hancei. Changes in calyx dimensions throughout the flowering-to-fruiting developmental stages were measured. Differences between floral and ambient temperatures were measured when only calyxes were retained. Additionally, differences in floral temperature between calyx-removed treatments and intact controls were also measured. All measurements were taken at three developmental stages: pre-anthesis, anthesis, and post-anthesis. Furthermore, seed production after calyx manipulation was examined at both anthesis and post-anthesis stages. The calyx exhibits continuous size enlargement from flowering to fruiting stages. After either artificial corolla removal or natural corolla abscission, the calyx independently maintains thermoregulatory capacity, sustaining floral temperatures significantly above ambient levels. Consequently, calyx removal resulted in markedly diminished floral temperature at both pre- and post-anthesis stages. In line with the thermoregulation results, progressive removal of the calyx showed a strong negative correlation with seed production. In contrast, removal of only the calyx edge generally maintained seed production at a level comparable to that of the intact control. Collectively, our findings demonstrate that the persistent calyx plays a critical role in elevating reproductive temperature under winter conditions, enhancing reproductive success in B. hancei through the maintenance of a favorable thermal conditions for reproduction. This study provides direct evidence that plant reproductive structures can markedly adapt to winter low-temperature stress through such a thermoregulatory mechanism. Full article

Edge, fog, and cloud continuum architectures that interconnect resource-constrained devices, intermediate edge servers, and remote cloud data centers face persistent challenges in handling heterogeneous and latency-sensitive workloads while reducing energy consumption and improving resource utilization. Classical task offloading approaches either rely on static heuristics, which lack adaptability to dynamic conditions, or on metaheuristic optimizers, which often incur high computational overhead and centralized coordination. This paper proposes LITO, a lemur-inspired task offloading algorithm for edge, fog, and cloud continuum systems that models the infrastructure as a social system in which computing nodes assume distinct roles that mirror lemur social hierarchies. Building on an abstracted model of lemur group behavior, LITO incorporates two key lemur-inspired mechanisms: an energy-aware task assignment mechanism based on sun basking, a thermoregulation behavior in which lemurs seek favorable warm spots, mapped here to selecting energetically efficient execution nodes, and a cooperative scheduling policy based on huddling, group clustering under stress, mapped here to sharing load among overloaded nodes. These mechanisms are combined with a continual supervised policy-learning layer with contextual bandit feedback that refines offloading decisions from online feedback. The resulting multi-objective formulation jointly minimizes energy consumption and deadline violations while maximizing resource utilization and throughput under high-load conditions in the edge and fog segment of the continuum. Simulations under diverse workload regimes and task complexities show that LITO outperforms representative multi-objective offloading baselines in terms of energy consumption, resource utilization, latency, Service Level Agreement (SLA) violations, and throughput in congested scenarios. Full article

Background: Ketamine and magnesium sulfate are commonly used perioperatively to prevent shivering, a frequent and clinically relevant complication of spinal and general anesthesia. Although their hypothermic effects are well documented, the neurotransmitter mechanisms underlying these effects remain insufficiently understood. This study examines whether serotonergic, adrenergic (α₂), and GABAergic (GABA_A) systems contribute to hypothermia induced by ketamine and a ketamine–magnesium sulfate combination. Methods: Body temperature was measured in Wistar rats after administration of ketamine (10 mg/kg) or the ketamine (5 mg/kg)–magnesium sulfate (5 mg/kg) combination. To assess neurotransmitter involvement, animals received yohimbine (α₂ antagonist), methysergide (non-selective 5-HT antagonist), or bicuculline (GABA_A antagonist) prior to ketamine or the drug combination. Data were analyzed using two-way repeated measures ANOVA followed by Tukey’s post hoc test. Results: Yohimbine at 0.5 and 1 mg/kg significantly potentiated ketamine-induced hypothermia, while only 3 mg/kg enhanced the effect of the ketamine–magnesium sulfate combination. Methysergide had a bidirectional influence: 1 mg/kg methysergide deepened ketamine-induced hypothermia, whereas 0.5 mg/kg methysergide attenuated the hypothermic effect of the ketamine–magnesium sulfate combination. Bicuculline (1–2 mg/kg) did not alter the hypothermic responses to ketamine or the combination. Conclusions: These findings indicate that ketamine- and ketamine–magnesium sulfate-induced hypothermia is primarily modulated by serotonergic and adrenergic mechanisms, whereas GABA_A receptor-dependent pathways do not appear to play a major role under the experimental conditions used. These results provide new mechanistic insights into NMDA antagonist–related thermoregulation and may help inform anesthetic strategies for shivering prevention and maintenance of perioperative thermal stability. Full article

Insects achieve millisecond sensor–motor loops with tiny sensors, compact neural circuits, and powerful actuators, embodying the principles of Edge AI. We present a comprehensive architectural blueprint translating insect neurobiology into a hardware–software stack: a latency-first control hierarchy that partitions tasks between a fast, dedicated Reflex Tier and a slower, robust Policy Tier, with explicit WCET envelopes and freedom-from-interference boundaries. This architecture is realized through a neuromorphic Reflex Island utilizing spintronic primitives, specifically MRAM synapses (for non-volatile, innate memory) and spin-torque nano-oscillator (STNO) reservoirs (for temporal processing), to enable instant-on, memory-centric reflexes. Furthermore, we formalize the biological governance mechanisms, demonstrating that, unlike conventional ICEs and miniturbines that exhibit narrow best-efficiency islands, insects utilize active thermoregulation and DGC (Discontinuous Gas Exchange) to maintain nearly constant energy efficiency across a broad operational load by actively managing their thermal set-point, which we map into thermal-debt and burst-budget controllers. We instantiate this integrated bio-inspired model in an insect-like IFEVS thruster, a solar cargo e-bike with a neuromorphic safety shell, and other safety-critical edge systems, providing concrete efficiency comparisons, latency, energy budgets, and safety-case hooks that support certification and adoption across autonomous domains. Full article

Traditional firefighting protective clothing materials, such as meta- and para-aramid fibers, provide significant thermal protection but often fail to adequately manage heat stress and moisture, especially due to the incorporation of semi-permeable membranes within the three-layer garment structure known as turnout gear. Integrating hydrogels into textiles for firefighting personal protective clothing (PPC) could enhance thermoregulation and moisture management, providing firefighters with improved comfort and safety. Hydrogels are three-dimensional, hydrophilic polymer networks capable of holding substantial amounts of water. Their high water content and excellent thermal properties make them ideal for cooling applications. Therefore, this review focuses on the potential of hydrogel-infused textiles to improve firefighters’ PPC by enhancing thermal comfort and moisture management. Specifically, hydrogel structures and engineered properties for enhanced performance are presented, including smart hydrogels and hydration customization mechanisms. Hydrogel integration into firefighting PPC for moisture management and improved thermoregulation is explored, including current and future market projections and state-of-the-art clinical trial findings. Overall, the future of hydrogel-integrated textiles for firefighting PPC is bright, with numerous advancements and trends poised to enhance the safety, comfort, and performance of protective gear. Full article

Global warming is increasingly constraining plant productivity by altering the photosynthetic energy balance and leaf thermoregulation. Under high light and elevated temperatures, absorption of energy in excess (AEE) by photosystem II disrupts photosynthetic electron transport, oxygen evolution, and CO₂ assimilation, often accompanied by reduced foliar transpiration. These conditions promote photoinhibition, as reflected by a decrease in maximal photosynthetic efficiency (Fv/Fm), an increase in non-photochemical quenching (NPQ), and photooxidative stress associated with enhanced reactive oxygen species (ROS) production. In addition to environmental heat stress, AEE influences foliar temperature through internal energy partitioning, including regulated dissipation of AEE as heat and changes in transpirational cooling. The relative contributions of NPQ, photochemistry, and transpiration to leaf temperature regulation are strongly context dependent and vary with light intensity, temperature changes, and water availability. Under global warming, rising background temperatures and increased vapor pressure deficit may constrain transpirational cooling and alter the balance between non-photochemical and photochemical energy dissipation and usage, respectively. In this review, we synthesize current knowledge on AEE handling, photoinhibition, NPQ and other quenching processes, and on transpiration cooling, and discuss a conceptual framework in which sustained imbalance among these processes under global warming conditions could amplify foliar heat stress and increase the risk of cellular damage. Rather than proposing new physiological mechanisms, this work integrates existing evidence across molecular, leaf, and ecosystem scales to highlight potential feedbacks relevant to plant performance under future climate prediction scenarios. Full article

Perimenopause and the menopausal transition are characterised by hormonal fluctuations that disrupt thermoregulation, metabolism, and sleep, contributing to adverse changes in body composition and increased cardiometabolic risk. Despite these challenges, food-based strategies to support sleep, appetite regulation, and metabolic health remain underexplored. This narrative review synthesised current evidence on the nutritional factors influencing these outcomes, with emphasis on the potential role of eggs as a nutrient-dense, accessible dietary option for midlife women. Literature searches identified studies examining hormonal mechanisms and the effects of nutrients abundant in eggs, including high-quality protein, choline, tryptophan, melatonin, vitamin D, and antioxidants. Evidence suggests that adequate protein and choline intake may enhance sleep duration, satiety, and preserve lean mass, while vitamin D and antioxidant compounds may support muscle function and mitigate oxidative stress associated with hormonal decline. Collectively, eggs represent a practical whole-food source of nutrients that may play a role in supporting sleep, appetite regulation, and body-composition maintenance during the menopausal transition; however, further high-quality intervention studies are needed to confirm these effects. Full article

Background/Objectives: Thermoregulation is essential for survival, with the hypothalamic preoptic area integrating peripheral signals to maintain core body temperature. While fever enhances immune responses, excessive hyperthermia causes cellular damage. Previous work has shown that central glucagon-like peptide-1 (GLP-1) receptor antagonism intensifies lipopolysaccharide (LPS)-induced fever, suggesting a role for GLP-1 signaling in temperature regulation. However, the direct effects of GLP-1 receptor agonists on fever remained unexplored. This study investigated the effects of liraglutide (LIRA), a GLP-1 analog used to treat diabetes and obesity, on temperature regulation and fever in rats, with a focus on sex-dependent mechanisms. Methods: Male and female Wistar rats received lipopolysaccharide (LPS, i.p.) to induce fever, followed by LIRA treatment (0.3 mg/kg, i.p.) one hour later. Body temperature was monitored for up to six hours post-LPS injection. Results: LIRA reduced body temperature in both euthermic and febrile rats of both sexes. LPS increased PGE₂ concentration in both sexes, with males showing a twofold increase compared to females. LIRA treatment reduced PGE₂ levels in LPS-challenged males (62%, p < 0.01) but not in female rats. LPS elevated interleukin (IL)-6 levels in both sexes, while LIRA treatment decreased IL-6 only in females (45%, p < 0.05). In males, LPS reduced hypothalamic serotonin (5-HT) levels, and LIRA further decreased 5-HT in saline-treated animals. In females, LIRA increased 5-HT levels (84%, p < 0.01) in LPS-challenged animals. Additionally, LIRA exhibited sex-specific effects on hypothalamic JNK phosphorylation, increasing activation in LPS-treated males and reducing it in LPS-treated females. Conclusions: LIRA demonstrates antipyretic properties through distinct, sex-specific mechanisms. In males, temperature reduction correlates with decreased hypothalamic PGE₂, whereas in females, antipyretic effects are associated with reduced IL-6, decreased JNK phosphorylation, and increased 5-HT. These findings reveal sexually dimorphic GLP-1R-mediated thermoregulatory pathways during inflammation. However, the causal relationships between these molecular changes and temperature regulation require further investigation, particularly regarding whether observed biochemical alterations represent primary mechanisms or secondary consequences of temperature modulation. Future studies should investigate the functional significance of the apparent contradiction in serotonergic responses between sexes. Full article

This study investigates the effects of rising temperatures on photosynthetic efficiency and stress tolerance in major Greek grapevine cultivars by using Sauvignon Blanc and Merlot as references. Muscat and Assyrtiko displayed the most heat-tolerant photosynthetic apparatus among the white cultivars, while Mavrodafni was the most heat-tolerant among the red ones, by effectively managing excess light energy. Sauvignon Blanc, although exhibiting heat susceptibility, maintained high photosystem II (PSII) functionality under heat stress by activating photoprotective mechanisms. Savvatiano and Agiorgitiko were more vulnerable to photo-oxidative stress above 35 °C, while Agiorgitiko maintained a functional photosynthetic apparatus, even at 40 °C, by shifting to a more photoprotective strategy. In contrast, Merlot, despite its resistance to photo-oxidative stress, lacked photoprotective investment, resulting in suppressed PSII under heat stress. Moschofilero was the most susceptible cultivar to photo-oxidative stress. Leaf morphological traits also contributed to heat stress tolerance, with smaller, thicker leaves facilitating thermoregulation. The present results provide important insights into specific responses to heat stress of major Greek grapevine cultivars. This knowledge may aid in selecting heat-tolerant genotypes and optimizing vineyard site selection, thereby enhancing the sustainability and climate resilience of viticulture. Full article

Incorporating phase change materials into asphalt concrete and utilizing phase change heat transfer to control the temperature of asphalt pavement can effectively reduce the impact of high temperatures on the durability of asphalt pavement. In this study, microencapsulated composite phase change materials were prepared using calcium alginate and polyethylene glycol (PEG) 1500 and mixed into SMA-13 Marshall specimens for indoor high-temperature tests. The test results show that the temperature of the specimen was reduced by about 1.5 °C when the doping amount of the composite phase change material was 2.4% and the oven temperature was 60 °C. In order to further investigate the application of phase change energy storage materials in asphalt pavement structure, this study used Comsol finite element software to simulate the summer temperature field of the asphalt surface layer. A three-layer asphalt pavement model consisting of 4 cm SMA-13, 6 cm AC-20, and 8 cm AC-25 was established to study the effect of phase change materials on the temperature change in the pavement. The results of this study show that adding 2.4% of the composite phase change material to each of the top and middle surface layers kept the temperature of all pavement layers outside of the temperature range in which the asphalt’s dynamic stability plunges. Full article

Skin, the largest organ of the human body, serves as a critical physico-chemical barrier against environmental insults and plays essential roles in hydration, thermoregulation, immune defense, and metabolic functions. Wound healing is a complex, multistage biological process involving hemostasis, inflammation, proliferation, and remodeling. Hydrogels have emerged as a promising class of wound dressings due to their high moisture retention, biocompatibility, and ability to mimic the extracellular matrix, thereby supporting accelerated healing and controlled drug delivery. This review provides a comprehensive overview of current hydrogel types—classified by origin, crosslinking mechanisms, and responsiveness to stimuli—and evaluates their use in experimental research on in vitro, ex vivo, and in vivo wound healing models. Furthermore, clinical applications of hydrogels in wound therapy are discussed. Advances in semisynthetic and stimuli-responsive hydrogels, along with improved testing models, offer enhanced therapeutic potential and underscore the need for continued innovation to optimize wound care outcomes and alleviate healthcare burdens. Full article

Background: Prader–Willi Syndrome (PWS) is a genetic neurodevelopmental disorder caused by an alteration of the paternal chromosome 15q11-q13. Youth with PWS present hyperphagia, increased fat/decreased muscle mass, hypotonia, and decreased metabolic rate with risk of obesity. Thermoregulation problems have been previously reported with hypothermia in adults or hyperthermia in children/infants with PWS. Methods: We retrospectively examined a cohort of 44 youths with PWS, 8–16 years old, presenting with a medical history of temperature dysregulation (TD), hypothermia or hyperthermia. Participants with (n = 10) and without (n = 34) a history of TD were compared for anthropometrics, body composition, medical history, and motor characteristics. Results: Youth with TD presented with hypothermia (n = 8), hyperthermia (n = 2), or both conditions (n = 2). Non-parametric statistics showed no significant differences in age, anthropometrics, body composition, or motor characteristics between the groups (p ≥ 0.064). Those with TD presented with a higher frequency of sleep apnea versus those without (50% vs. 18%; p = 0.038). Conclusions: The prevalence of TD in the cohort was one in five youth with PWS, suggesting that the problem is not isolated. The results do not suggest that anthropometrics, body composition, or motor characteristics explain differences in temperature excursions in youths with PWS. Possible physiological mechanisms and future research are discussed. Full article

Infants are at a higher risk of heat-related morbidity and mortality compared to children and adults. However, it remains unclear whether this vulnerability stems from immature thermoregulatory mechanisms or simply from their dependence on caregivers. This narrative review examines current literature on infant thermoregulation during heat exposure and explores how unique physiological characteristics may influence vulnerability. Key differences in infants compared to older individuals include their larger surface area-to-mass ratio, which (1) facilitates heat dissipation when skin temperature exceeds ambient temperature, but compromises heat loss in reversed conditions, and (2) likely enables a large portion of an infant’s blood volume to shift to the skin, promoting heat loss but reducing blood volume in the central circulation. Infants also have a relatively high metabolic heat production. Additionally, their lower sweat output per gland may represent either a limitation or a different thermoregulatory strategy. Contrary to common assumptions, most components of infants’ thermoregulatory system do not appear inherently immature; rather, their distinct physiological characteristics—combined with their reliance on caregivers—shape how and when heat exposure may become harmful. Nevertheless, further research is needed to better understand how these interacting factors influence infants’ ability to maintain stable core temperature. Meanwhile, coordinated efforts by caregivers, health professionals, and policymakers are essential to minimize infants’ heat-related health risks. Full article

A series of studies was conducted on the functional and structural characteristics of polymer composite materials (PCMs) based on silicone polymers modified with multi-walled carbon nanotubes (MWCNTs) and metallic particles (CuAl or Al). The influence of the structural parameters of carbon and metallic inclusions in the polymer matrix on the electrophysical and thermophysical properties of the composites was demonstrated. Various conduction mechanisms dominating in the inverse temperature ranges of 50 K^–1–13 K^–1, 13 K^–1–6 K^–1, and 6 K^–1–2 K^–1 were identified. The operational modes of the polymer composites as active materials for thermoregulating coatings were established. The highest temperature of 32.9 °C in operating mode and the shortest warm-up time of 180 s were observed in the composite modified with 4 wt.% CNTs and 10 wt.% bronze particles at a supply voltage of 10 V. The characteristics of the composites under atomic oxygen (AO) exposure with a fluence of 3 × 10²¹ atoms/cm² was evaluated, confirming their functionality, particularly for potential space applications. The composites demonstrated nearly complete retention of their functional characteristics. The aim of this study was to develop electrically conductive functional composites based on silicone polymers containing MWCNTs and metallic particles inclusions for creating electric heating elements with tailored functional characteristics. Full article