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The non-aqueous solid-liquid biphasic solvent of 2-amino-2-methyl-1-propanol (AMP)/piperazine (PZ)/dipropylene glycol dimethyl ether (DME) features a high CO2 absorption loading, favorable phase separation behavior and high regeneration efficiency. Different with the liquid-liquid phase change solvent, the reaction kinetics of CO2 capture into solid-liquid biphasic solvent was rarely studied. In the present work, the reaction kinetics of CO2 absorption into AMP/PZ/DME solid-liquid biphasic solvent was investigated into the double stirred kettle reactor. The absorption reaction followed a pseudo-first-order kinetic model according to the zwitterion mechanism. The overall reaction rate constant (kov) and the enhancement factor (E) of CO2 absorption both increased with increasing temperature. The total mass transfer resistance of the absorbent decreased with increasing temperature and increased with increasing absorption loading, so the higher reaction temperature was conducive to the absorption, and the liquid phase mass transfer resistance was the main factor affecting the absorption rate.

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[Purpose] The effects of multifunctional garments on neuromuscular performance have gained significant research attention in the health sciences. However, the spinal responses to different fabrics have not yet been considered. In the present study, we examined the effects of typical fabrics (cotton and polyester) on the Hoffmann reflex during local heat exposure. [Participants and Methods] Sixteen healthy males aged 20-40 years participated in this study. A heating device comprising a thermal mat, fabric, and a data logger was fabricated. The fabric was affixed to the skin as the contact surface. The temperature of the right posterior lower leg was increased to 39°C followed by 10 min for adaptation at 39-40°C. The H- and M-waves were recorded at each point, including those without heating. An identical trial was conducted seven days later using the alternative fabric. [Results] M-wave amplitude and latency were significantly decreased during heat exposure without fabric. The H-wave latency was prolonged by sustained thermal heat during the session with polyester. Interestingly, the H-wave amplitudes normalized by the maximal M-wave amplitudes decreased with prolonged heat exposure during the session with cotton. However, this index remains unchanged during the sessions using polyester. [Conclusion] During prolonged localized thermal exposure, cotton reduced spinal excitability, whereas polyester preserved spinal excitability.

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Previous evidence on heatwaves' impact on mental health outpatient visits is limited, especially uncertainty on how different heatwave definitions affect this relationship. In this time-series study, we assessed the association between heatwaves and outpatient visits for mental disorders in Guangzhou, China. Daily outpatient visits for mental disorders and its specific categories (schizophrenia, mood, and neurotic disorders) were sourced from the Urban Resident-based Basic Medical Insurance (URBMI) and the Urban Employee-based Basic Medical Insurance (UEBMI) claims databases in Guangzhou from 2010 to 2014. The study employed nine heatwave definitions, based on combinations of three daily mean temperature thresholds (90th, 92.5th, and 95th percentiles) and durations (2, 3, and 4 days). Using quasi-Poisson generalized linear models (GLMs), we estimated the risks (at lag 0 day) and cumulative effects (lag 0-10 days) of heatwaves on mental disorder outpatient visits. Age, gender, types of medical insurance were considered as potential effect modifiers. We observed a positive association between heatwaves and increased total outpatient visits for mental disorders, both at lag 0 day and during lag 0-10 days. The impact of heatwave was significant at lag 0 day for schizophrenia, mood and neurotic disorders visits, it remained significant for neurotic and mood disorders visits during lag 0-10 days. Heatwave durations lasting more than 4 days were associated with higher relative risks of mental disorders at lag 0 day. Older adults had relatively higher effect estimations than younger individuals. This research highlights the effects of extreme heat on mental health.

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Ion beam-induced heat damage in thermally low conductive specimens such as biological samples is gaining increased interest within the scientific community. This is partly due to the increased use of FIB-SEMs in biology as well as the development of complex materials, such as polymers, which need to be analyzed. The work presented here looks at the physics behind the ion beam-sample interactions and the effect of the incident ion energy (set by the acceleration voltage) on inducing increases in sample temperature and potential heat damage in thermally low conductive materials such as polymers and biological samples. The ion beam-induced heat for different ion beam currents at low acceleration voltages is calculated using Fourier's law of heat transfer, finite element simulations, and numerical modelling results and compared to experiments. The results indicate that with lower accelerator voltages, higher ion beam currents in the nanoampere range can be used to pattern or image soft material and non-resin-embedded biological samples with increased milling speed but reduced heat damage.

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This study investigates the effects of heat and ultrasonic treatments on the physicochemical parameters and rennet-induced coagulation properties of milk from a variety of species, including cow, goat, buffalo, and donkey. Milk samples were subjected to heat treatments at different temperatures (65 °C, 80 °C, 90 °C, 100 °C) and ultrasonic treatment at varying power levels (200 W, 400 W, 600 W, 800 W, 1000 W). The results revealed that changes in turbidity, particle size, zeta potential, secondary structure, and surface hydrophobicity were altered by both ultrasonic and heat treatments, as well as the kind of milk. Ultrasonic treatment of cow milk decreased α-helix content while increasing ß-turn content. Under similar ultrasonic treatment, goat milk showed a considerable increase in ß-sheet content, whereas ß-turn and random coil contents decreased compared to control samples. Notably, the water-holding capacity of gels formed from all four types of milk increased significantly with the intensity of ultrasonic and heat treatments. The hardness of buffalo milk gels increased significantly after ultrasonic and thermal treatments, ranging from 63 °C for 30 min to 90 °C for 15 min, but the hardness of cow and goat milk gels increased in varying degrees compared to their control samples. Furthermore, gels from cow and goat milk had higher storage modulus (G') and loss modulus (G'') than those from buffalo and donkey milk, and changes in G' and G'' from the examined milk were altered by ultrasonic and heat treatments. These findings offer important insights into refining milk processing procedures to improve dairy product quality and usefulness.

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Heat-gelatinized starch (HGS), which is prepared via heat treatment, enhances viscosity and provides suitable thickening properties, which improve water retention in products. This study aimed to investigate the potential of blending gelatinized starch with edible hydrocolloids (guar gum, carrageenan (C), locust bean gum, konjac powder, and sodium alginate) to assess their effect on the stabilization of starch gelatinization and reduction of retrogradation. Optical microscopic observations revealed the disrupted structures of gelatinized starch after heat treatments, along with diminished or absent birefringence. Adding C to the gelatinized starch reduced its peak viscosity, breakdown and setback value. For the rheological analysis, heat gelatinization and hydrocolloid addition contributed to the increased elasticity and viscosity of samples. Gelatinization and hydrocolloid addition emerged as effective strategies for improving starch quality. Although it still warrants further exploration, the introduced approach holds potential for applications in the development of convenience and canned food products.

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Recently, the impacts of climate change, notably ocean warming and solar ultraviolet radiation, have led to significant stress and mortality in cnidarians. The objective of this study is to decode the metabolic responses of sea anemones Entacmaea quadricolor and upside-down jellyfish Cassiopea andromeda upon exposure to thermal and ultraviolet stress. Gas chromatography-mass spectrometry and ultraperformance liquid chromatography coupled with high-resolution mass spectrometry targeting polar and non-polar metabolites were applied. In total, 72 polar and 242 lipophilic metabolites were detected in jellyfish and sea anemones, respectively. Amino acids are the major metabolite class in jellyfish, and triacylglycerides are the predominant lipids in jellyfish and anemones. Exposure to stressors led to metabolic alterations, marked by elevated amino acids in jellyfish and increased amino acids and sugar alcohols in sea anemones at 34 °C and after four days of ultraviolet radiation. Non-polar metabolome analysis indicated distinct responses to ultraviolet radiation and thermal stress in both species.

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INTRODUCTION: Myocardial ischemia-reperfusion injury (MIRI) remains a prevalent clinical challenge globally, lacking an ideal therapeutic strategy. Macrophages play a pivotal role in MIRI pathophysiology, exhibiting dynamic inflammatory and resolutive functions. Macrophage polarization and metabolism are intricately linked to MIRI, presenting potential therapeutic targets. Pubescenoside C (PBC) from Ilex pubescens showed significantly anti-inflammatory effects, however, the effect of PBC on MIRI is unknown. OBJECTIVES: This study aimed to assess the cardioprotective effects of PBC against MIRI and elucidate the underlying mechanisms. METHODS: Sprague-Dawley rats, H9c2 and RAW264.7 macrophages were used to establish the in vitro and in vivo models of MIRI. TTC/Evans blue staining, immunohistochemical staining, metabonomics analysis, chemical probe, surface plasmon resonance (SPR), co-immunoprecipitation (CO-IP) assays were used for pharmacodynamic and mechanism study. RESULTS: PBC administration effectively reduced myocardial infarct size, decreased ST-segment elevation, and lowered CK-MB levels, concurrently promoting macrophage M2 polarization in MIRI. Furthermore, PBC-treated macrophages and their conditioned culture medium attenuated the apoptosis of H9c2 cells induced by oxygen-glucose deprivation/reoxygenation (OGD/R). Metabonomics analysis revealed that PBC increased the production of itaconic acid (ITA) and malic acid (MA) in macrophages, which conferred protection against OGD/R injury in H9c2 cells. Mechanistic investigations indicated that ITA exerted its effects by covalently modifying pyruvate kinase M2 (PKM2) at Cys474, Cys424, and Lys151, thereby facilitating PKM2's mitochondrial translocation and enhancing the PKM2/Bcl2 interaction, subsequently leading to decreased degradation of Bcl2. SPR assays further revealed that PBC bound to HSP90, facilitating the interaction between HSP90 and GSK3ß and resulting in the inactivation of GSK3ß activity and upregulation of key metabolic enzymes for ITA and MA production (Acod1 and Mdh2). CONCLUSION: PBC alleviates MIRI-induced cardiomyocyte apoptosis by modulating the HSP90/ITA/PKM2 axis. Furthermore, pharmacological upregulation of ITA emerges as a promising therapeutic approach for MIRI, hinting at PBC's potential as a candidate drug for MIRI therapy.

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Physical training in heat or hypoxia can improve physical performance. The purpose of this parallel group study was to investigate the concurrent effect of training performed simultaneously in heat (31 °C) and hypoxia (FIO2 = 14.4%) on anaerobic capacity in young men. For the study, 80 non-trained men were recruited and divided into 5 groups (16 participants per group): control, non-training (CTRL); training in normoxia and thermoneutral conditions (NT: 21 °C, FIO2 = 20.95%); training in normoxia and heat (H: 31 °C, FIO2 = 20.95%); training in hypoxia and thermoneutral conditions (IHT: 21 °C, FIO2 = 14.4%), and training in hypoxia and heat (IHT + H: 31 °C, FIO2 = 14.4%). Before and after physical training, the participants performed the Wingate Test, in which peak power and mean power were measured. Physical training lasted 4 weeks and the participants exercised 3 times a week for 60 min, performing interval training. Only the IHT and IHT + H groups showed significant increases in absolute peak power (p < 0.001, ES = 0.36 and p = 0.02, ES = 0.26, respectively). There were no significant changes (p = 0.18) after training in mean power. Hypoxia appeared to be an environmental factor that significantly improved peak power, but not mean power. Heat, added to hypoxia, did not increase cycling anaerobic power. Also, training only in heat did not significantly affect anaerobic power. The inclusion of heat and/or hypoxia in training did not induce negative effects, i.e., a reduction in peak and mean power as measured in the Wingate Test.

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In this study, a wearable and highly stretchable organic thermoelectric (TE) generator with a notable power density is developed. A highly stretchable and solution-processable TE/electrode pattern is realized by stepwise-curing elastomeric and conducting network. Significant advances in the TE or electrical properties are obtained for these stretchable patterns through post-activation treatment, which creates long-range charge transport pathways without degrading pre-established elastomeric networks. The TE and electrode patterns are solution-processed to a stretchable template, so that all-stretchable TE generator is realized. The fabricated TE generator maintains 90% of its maximum TE power output at 40% stretching stress and shows a stable TE power output after 200 stretching cycles. The TE generator maintains its stretchability in highly densified patterns, as the highly stretchable TE/electrode patterns enable good stretchability with little aid of the stretchable template. So, the TE generator has a high power density of 0.32 nW cm-2 K-2, one of the highest values among stretchable TE generators to date.

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A preview of how effective behavioral, biological and technological responses might be in the future, when outdoor conditions will be at least 2°C hotter than current levels, is available today from studies of individuals already living in extreme heat. In areas where high temperatures are common-particularly those in the hot and humid tropics-several studies report that indoor temperatures in low-income housing can be significantly hotter than those outdoors. A case study indicates that daily indoor heat indexes in almost all the 123 slum dwellings monitored in Kolkata during the summer were above 41°C (106°F) for at least an hour. Economic constraints make it unlikely that technological fixes, such as air conditioners, will remedy conditions like these-now or in the future. People without access to air conditioning will have to rely on behavioral adjustments and/or biological/physiological acclimatization. One important unknown is whether individuals who have lived their entire lives in hot environments without air conditioning possess natural levels of acclimatization greater than those indicated by controlled laboratory studies. Answering questions about the future will require more studies of heat conditions experienced by individuals, more information on indoor versus outdoor heat conditions, and a greater understanding of the behavioral and biological adjustments made by people living today in extremely hot conditions.

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Purpose: This research investigated the pre-, per- and post cooling strategies used by competitive tennis players from various levels of play who occasionally train and compete in hot (>28°C) and humid (>60% rH), and dry (<60% rH) environments. Methods: 129 male tennis players (Mage = 24.9) competing at regional (N = 54), national (N = 30) and international (N = 45) levels, completed an online questionnaire regarding their use (i.e., timing, type, justification and effectiveness) of pre- (i.e., before practice), per- (i.e., during exercise) and post-cooling strategies when playing tennis in hot dry (HD) and hot humid (HH) conditions. Individual follow-up interviews were also carried on 3 participants to gain an in-depth understanding of the player's experience. Results: Competitive tennis players used both internal and external cooling strategies to combat the negative effects of HD and HH conditions, but considered the HH to be more stressful than HD and experienced more heat-related illness in HH environments. International players used cold packs and cold towel more frequently than the regional and national players in hot environments, and used cold water immersion and cold vest more frequently than the latter in HH. Differences in strategy use were mostly observed during per-cooling where regional and national players more frequently used cold drinks than international players who more frequently used cold packs in HD and cold towel in HH conditions. Moreover the latter more frequently used cold towel, cold packs and cold water immersion as post-cooling strategies than regional players. Conclusion: When playing tennis in the heat, it is strongly recommended to employ cooling strategies to maintain health, limit declines in performance, and promote recovery. We also recommend improving education regarding the appropriate use and effectiveness of cooling strategies, and increasing their availability in tournaments.

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Fused filament fabrication (FFF) is one of the most popular additive manufacturing (AM) processes due to its simplicity and low initial and maintenance costs. However, good printing results such as high dimensionality, avoidance of cooling cracks, and warping are directly related to heat control in the process and require precise settings of printing parameters. Therefore, accurate prediction and understanding of temperature peaks and cooling behavior in a local area and in a larger part are important in FFF, as in other AM processes. To analyze the temperature peaks and cooling behavior, we simulated the heat distribution, including convective heat transfer, in a cuboid sample. The model uses the finite difference method (FDM), which is advantageous for parallel computing on graphics processing units and makes temperature simulations also of larger parts feasible. After the verification process, we validate the simulation with an in situ measurement during FFF printing. We conclude the process simulation with a parameter study in which we vary the function of the heat transfer coefficient and part size. For smaller parts, we found that the print bed temperature is crucial for the temperature gradient. The approximations of the heat transfer process play only a secondary role. For larger components, the opposite effect can be observed. The description of heat transfer plays a decisive role for the heat distribution in the component, whereas the bed temperature determines the temperature distribution only in the immediate vicinity of the bed. The developed FFF process model thus provides a good basis for further investigations and can be easily extended by additional effects or transferred to other AM processes.

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Advances in manufacturing technologies and materials are crucial to the commercial deployment of energy technologies. We present the case of concentrating solar power (CSP) with molten salt (MS) thermal storage, where low-cost, high-efficiency heat exchangers (HXs) are needed to achieve cost competitiveness. The materials required to tolerate the extreme operating conditions in CSP systems make it difficult or infeasible to produce them using conventional manufacturing processes. Although it is technically possible to produce HXs with adequate performance using additive manufacturing, specifically laser powder bed fusion (LPBF), here we assess whether doing so is cost-effective. We describe a process-based cost model (PBCM) to estimate the cost of fabricating a MS-to-supercritical carbon dioxide HX using LPBF. The PBCM is designed to identify modifications to designs, process choices, and manufacturing innovations that have the greatest effect on manufacturing cost. Our PBCM identified HX design and LPBF process modifications that reduced projected HX cost from $750 per kilo-Watt thermal (kW-th) ($8/cm3) to $350/kW-th ($6/cm3) using currently available LPBF technology, and down to $220/kW-th ($4/cm3) with improvements in LPBF technology that are likely to be achieved in the near term. The PBCM also informed a redesign of the HX design that reduced projected costs to $140-160/kW-th ($3/cm3).

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Laser additive manufacturing (LAM) technology has the advantages of short manufacturing cycles, low material waste rate, and design ability. It is especially suitable for preparing functionally gradient materials (FGM). However, due to the large temperature gradient and the change in material composition, the residual stress is very high, which will seriously affect the mechanical properties and manufacturing accuracy of the structure. In this study, the thermomechanical coupled finite element model based on the Bessel heat source is established, and the residual stress in LAM TC4/TC11 FGM is obtained. The results show that the Bessel heat source can effectively suppress the generation of residual stress in the additive manufacturing process, and the finite element results are consistent with the experimental results. Compared with the traditional Gaussian heat source, the maximal residual tensile stress is reduced by an average of 28.1%. The value of residual stress increases with the increase in the number of printing layers, and it increases with the increase of the laser power and decreases with the increase of the scanning speed. The overall trend is that the two sides are compressive stress and the middle is tensile stress. The research has important reference significance for the reasonable suppression of the residual stress in FGM produced by LAM.

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Shape memory alloys (SMAs) with large latent heat absorbed/released during phase transformation at elevated temperatures benefit their potential application on thermal energy storage (TES) in high temperature environment like power plants, etc. The desired alloys can be designed quickly by searching the vast component space of doped NiTi-based SMAs via data-driven method, while be challenging with the noisy experimental data. A noise-aware active learning strategy is proposed to accelerate the design of SMAs with large latent heat at elevated phase transformation temperatures based on noisy data. The optimal noise level is estimated by minimizing the model error with incorporation of a range of noise levels as noise hyper-parameters into the noise-aware Kriging model. The employment of this strategy leads to the discovery of the alloy with latent heat of -36.08 J g-1, 9.2% larger than the best value (-33.04 J g-1) in the original training dataset within another four experiments. Additionally, the alloy represents high austenite finish temperature (481.71°C) and relatively small hysteresis. This promotes the latent heat TES application of SMAs in high temperature circumstance. It is expected that the noise-aware approach can be convenient for the accelerated materials design via the data-driven method with noisy data.

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In the wake of rising earth temperature, chickpea crop production is haunted by the productivity crisis. Chickpea, a cool season legume manifests tolerance in several agro-physiological level, which is complex quantitative in nature, and regulated by multiple genes and genetic networks. Understanding the molecular genetic basis of this tolerance and identifying key regulators can leverage chickpea breeding against heat stress. This study employed a genomics-assisted breeding strategy utilizing multi-locus GWAS to identify 10 key genomic regions linked to traits contributing to heat stress tolerance in chickpea. These loci subsequently delineated few key candidates and hub regulatory genes, such as RAD23b, CIPK25, AAE19, CK1 and WRKY40, through integrated genomics, transcriptomics and interactive analyses. The differential transcript accumulation of these identified candidates in contrasting chickpea accessions suggests their potential role in heat stress tolerance. Differential ROS accumulation along with their scavengers' transcript abundance aligning with the expression of identified candidates in the contrasting chickpea accessions persuade their regulatory significance. Additionally, their functional significance is ascertained by heterologous expression and subsequent heat stress screening. The high confidence genomic loci and the superior genes and natural alleles delineated here has great potential for swift genomic interventions to enhance heat resilience and yield stability in chickpea.

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BACKGROUND: The vast majority of pancreatic cancers have been shown to be insensitive to single-agent immunotherapy. Exploring the mechanisms of immune resistance and implementing combination therapeutic strategies are crucial for PDAC patients to derive benefits from immunotherapy. Deletion of BAP1 occurs in approximately 27% of PDAC patients and is significantly correlated with poor prognosis, but the mechanism how BAP1-deletion compromises survival of patients with PDAC remain a puzzle. METHODS: Bap1 knock-out KPC (KrasG12D/+; LSLTrp53R172H/+; Pdx-1-Cre) mice and control KPC mice, syngeneic xenograft models were applied to analysis the correlation between BAP1 and immune therapy response in PDAC. Immunoprecipitation, RT-qPCR, luciferase and transcriptome analysis were combined to revealing potential mechanisms. Syngeneic xenograft models and flow cytometry were constructed to examine the efficacy of the inhibitor of SIRT1 and its synergistic effect with anti-PD-1 therapy. RESULT: The deletion of BAP1 contributes to the resistance to immunotherapy in PDAC, which is attributable to BAP1's suppression of the transcriptional activity of HSF1. Specifically, BAP1 competes with SIRT1 for binding to the K80 acetylated HSF1. The BAP1-HSF1 interaction preserves the acetylation of HSF1-K80 and promotes HSF1-HSP70 interaction, facilitating HSF1 oligomerization and detachment from the chromatin. Furthermore, we demonstrate that the targeted inhibition of SIRT1 reverses the immune insensitivity in BAP1 deficient PDAC mouse model. CONCLUSION: Our study elucidates an unrevealed mechanism by which BAP1 regulates immune therapy response in PDAC via HSF1 inhibition, and providing promising therapeutic strategies to address immune insensitivity in BAP1-deficient PDAC.

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Wet-bulb globe temperature (WBGT)-a standard measure for workplace heat stress regulation-incorporates the complex, nonlinear interaction among temperature, humidity, wind and radiation. This complexity requires WBGT to be calculated iteratively following the recommended approach developed by Liljegren and colleagues. The need for iteration has limited the wide application of Liljegren's approach, and stimulated various simplified WBGT approximations that do not require iteration but are potentially seriously biased. By carefully examining the self-nonlinearities in Liljegren's model, we develop a zero-iteration analytic approximation of WBGT while maintaining sufficient accuracy and the physical basis of the original model. The new approximation slightly deviates from Liljegren's full model-by less than 1°C in 99% cases over 93% of global land area. The annual mean and 75%-99% percentiles of WBGT are also well represented with biases within ± 0.5 °C globally. This approximation is clearly more accurate than other commonly used WBGT approximations. Physical intuition can be developed on the processes controlling WBGT variations from an energy balance perspective. This may provide a basis for applying WBGT to understanding the physical control of heat stress.

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Objectives: Few studies have examined the impact of healthy sleep among general workers on individuals and society. Therefore, the status and risk factors of sleep disturbances among general workers were investigated. In addition, this study assessed the degree to which cold and heat symptoms are associated with sleep disturbances. Methods: A nationwide cross-sectional study was conducted through an online questionnaire focused on sleep disturbances of the general public in 2021. The degree of cold-heat pattern Identification (CHPI) of the general public was also surveyed. Descriptive statistics and multivariate logistic regression were used to derive the study results. Results: Data from 2,822 workers out of 3,900 valid questionnaires were analyzed. Approximately half of the respondents (49.93%) had sleep disturbances. Among the types of work, self-employed, two-shift work, and working more than 53 hours were associated with sleep disturbances. Sleep disturbances were positively associated with six cold and heat symptoms three cold symptoms (coldness of the abdomen, coldness of body, and pale face) and three heat symptoms (body feverishness, feverishness of the limbs, and drinking cold water). Conclusion: Customized policies to maintain healthy work are needed for self-employed work, two-shift work, and long working hours, which are risk factors for workers' sleep disturbances. In addition, medical personnel can effectively diagnose and treat sleep disturbances considering the worker's cold and heat symptoms.