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This study evaluates the applicability of three thermal comfort indices-Physiologically Equivalent Temperature (PET), Standard Effective Temperature (SET), and Universal Thermal Climate Index (UTCI)-in various outdoor environments on the campus of Xi'an University, China. Meteorological data were collected on sunny days using a portable weather station at a height of 1.5 m, and subjective questionnaires were administered to 25 healthy university students over three months to gather Thermal Sensation Votes (TSV) and Thermal Comfort Votes (TCV). The study was conducted at four distinct outdoor locations: a lakeside area (Location 1), a shaded path (Location 2), a sports field (Location 3), and a plaza (Location 4). PET, SET, and UTCI values were calculated from the collected data using Rayman software. The analysis revealed significant differences in thermal comfort across the four locations, with the highest proportion of subjects feeling hot at the sports field (54.4%) and the highest proportion feeling cold at the lakeside (39%). The shaded path had the highest proportion of subjects feeling comfortable (79.4%), while the lakeside had the lowest (60.1%). The results indicated that SET underestimated thermal sensation at Locations 1, 3, and 4, necessitating calibration. PET was suitable for Locations 2, 3, and 4 but failed to reflect the thermal sensation at Location 1 due to prolonged sun exposure. In contrast, UTCI demonstrated applicability across all locations. To enhance accuracy, revised indices SET' and PET' were formulated using the mean-median method, providing more precise thermal comfort assessments. These findings underscore the limitations of SET and PET under specific conditions and highlight the robustness of UTCI, offering valuable insights for urban planning and design aimed at improving outdoor thermal comfort and well-being.
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Sensación Térmica , Humanos , Universidades , Masculino , Femenino , Adulto Joven , Sensación Térmica/fisiología , Estudiantes , Temperatura , Adulto , China , Encuestas y CuestionariosRESUMEN
Transient receptor potential (TRP) ion channels serve as sensors for variations in ambient temperature, modulating both thermoregulation and temperature responsive cellular processes. Among these, the vanilloid TRP subfamily (TRPV) comprises six members and at least four of these members (TRPV1-TRPV4) have been associated with thermal sensation. TRPV2 has been described as a sensor for noxious heat, but subsequent studies have unveiled a more complex role for TRPV2 beyond temperature perception. This comprehensive review aims to elucidate the intricate thermosensitivity of TRPV2 by synthesizing current knowledge on its biophysical properties, expression pattern and known physiological functions associated with thermosensation.
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Canales Catiónicos TRPV , Sensación Térmica , Canales Catiónicos TRPV/metabolismo , Humanos , Animales , Sensación Térmica/fisiología , Regulación de la Temperatura Corporal/fisiologíaRESUMEN
INTRODUCTION: The olfactory and trigeminal system are closely interlinked. Existing literature has primarily focused on characterizing trigeminal stimulation through mechanical and chemical stimulation, neglecting thermal stimulation thus far. The present study aimed to characterize the intranasal sensitivity to heat and the expression of trigeminal receptors (transient receptor potential channels, TRP). METHODS: A total of 20 healthy participants (aged 21-27 years, 11 women) were screened for olfactory function and trigeminal sensitivity using several tests. Under endoscopic control, a thermal stimulator was placed in 7 intranasal locations: anterior septum, lateral vestibulum, interior nose tip, lower turbinate, middle septum, middle turbinate, and olfactory cleft to determine the thermal threshold. Nasal swabs were obtained in 3 different locations (anterior septum, middle turbinate, olfactory cleft) to analyze the expression of trigeminal receptors TRP: TRPV1, TRPV3, TRPA1, TRPM8. RESULTS: The thermal threshold differed between locations (p = 0.018), with a trend for a higher threshold at the anterior septum (p = 0.092). There were no differences in quantitative receptor expression (p = 0.46) at the different sites. The highest overall receptor RNA expression was detected for TRPV1 over all sites (p<0.001). The expression of TRPV3 was highest at the anterior septum compared to the middle turbinate or the olfactory cleft. The thermal sensitivity correlated with olfactory sensitivity and results from tests were related to trigeminal function like intensity ratings of ammonium, a questionnaire regarding trigeminal function, nasal patency, and CO2 thresholds. However, no correlation was found between receptor expression and psychophysical measures of trigeminal function. DISCUSSION: This study provided the first insights about intranasal thermal sensitivity and suggested the presence of topographical differences in thermal thresholds. There was no correlation between thermal sensitivity and trigeminal mRNA receptor expression. However, thermal sensitivity was found to be associated with psychophysical measures of trigeminal and olfactory function.
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Mucosa Nasal , Canales Catiónicos TRPV , Humanos , Femenino , Adulto , Masculino , Mucosa Nasal/metabolismo , Adulto Joven , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/genética , Calor , Nervio Trigémino/fisiología , Nervio Trigémino/metabolismo , Umbral Sensorial/fisiología , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/genética , Canales Catiónicos TRPM/metabolismo , Canales Catiónicos TRPM/genética , Sensación Térmica/fisiología , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genéticaRESUMEN
Thermal comfort in an office impacts physical health, stress, and productivity. Humidity affects thermal comfort; however, the underlying mechanism remains unclear. This study assessed the influence of humidity on body temperature, thermal comfort, stress, and their relationship in working individuals. Thirteen participants performed three sets of 20-min calculation tasks followed by a 10-min rest in 26 °C or 33 °C with relative humidity (RH) of 30 % or 60 %. Core body temperature (Tcore), mean skin surface temperature (Tskin), and electrocardiogram were continuously recorded. Subjective thermal sensations and comfort were assessed with visual analog scales. Stress level was estimated based on α-amylase activity and immunoglobulin A level in saliva and heart rate variability. Mean Tskin and Tcore elevated at 33 °C with 60 % RH, where warm sensation and thermal discomfort also increased. Heart rate variability reflecting parasympathetic nerve activity decreased. There was a negative linear relationship between weighted body temperature and thermal comfort. However, thermal discomfort was augmented at a given weighted body temperature at 60 % RH. Thus, under indoor working conditions, high humidity may augment thermal discomfort and become a stress factor. Increases in Tskin and Tcore are involved in the mechanism, alongside other factors.
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Temperatura Corporal , Frecuencia Cardíaca , Humedad , Saliva , Humanos , Masculino , Frecuencia Cardíaca/fisiología , Temperatura Corporal/fisiología , Adulto Joven , Adulto , Saliva/metabolismo , Saliva/química , Femenino , Sensación Térmica/fisiología , Electrocardiografía , alfa-Amilasas/metabolismo , Temperatura Cutánea/fisiología , Estrés Psicológico/fisiopatología , Inmunoglobulina A/metabolismo , Estrés Fisiológico/fisiología , Condiciones de TrabajoRESUMEN
Sex difference stands as a crucial factor necessitating consideration in personalized thermal environment control, with the mechanisms of its emergence potentially differing across different thermal environments. However, a comparative analysis of sex differences regarding body temperature (skin and core body temperature) and thermal perception across different environments is lacking. A stable environmental experiment (comprising three conditions: 16 °C, 20 °C, and 24 °C) and a transient environmental experiment (involving a whole-body step-change from 19 °C to 35 °C and back to 19 °C) were conducted, with participation from 20 young males and 20 young females. Skin temperature and core body temperature were continuously recorded during the experiments, and three types of thermal perceptions were regularly collected. The results showed that: (1) The impact of thermal environment on females' skin temperature surpassed that on males, in stable environment, with every 1 °C rise in ambient temperature, the mean skin temperature increased by 0.28 °C for males and 0.35 °C for females respectively; in transient environment, females' mean skin temperature raise and fell at a faster rate. (2) Males exhibited stronger thermal regulation abilities than females, particularly evident during sudden increase in ambient temperature (from 19 °C to 35 °C), where the reduction magnitude of males' core body temperature was notably larger. (3) Whether in stable or transient environments, significant sex differences often occurred in skin temperature and thermal sensation at distal parts, particularly at the hand. (4) Males typically fed back higher levels of thermal comfort and thermal acceptability than females, suggesting that in addition to physiological sex differences, psychological sex distinctions also play a role. In summary, personalized design for stable thermal environment can focus on sex differences in skin temperature, while transient thermal environment requires consideration of both skin temperature and core body temperature. A comprehensive consideration of physiological and psychological sex differences aids in creating personalized thermal environments with greater precision.
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Temperatura Corporal , Humanos , Masculino , Femenino , Temperatura Cutánea/fisiología , Adulto Joven , Regulación de la Temperatura Corporal/fisiología , Factores Sexuales , Sensación Térmica/fisiología , Temperatura , Adulto , Caracteres SexualesRESUMEN
ABSTRACT: The thermal grill illusion (TGI), a phenomenon in which the juxtaposition of innocuous warm and cold temperatures on the skin elicits a burning sensation, offers a unique perspective to how pain occurs in response to harmless stimuli. We investigated the role of the spinal cord in the generation of the TGI across 2 experiments (total n = 80). We applied heat and cold stimuli to dermatomes, areas of skin innervated by a single spinal nerve, that mapped onto adjacent or nonadjacent spinal segments. Enhanced warm and burning ratings during the TGI were observed when cold and warm stimuli were confined within the same dermatome. Furthermore, we found the spatial organisation of warm and cold stimuli within and across dermatomes affected TGI perception. Perceived warmth and burning intensity increased when the cold stimulus projected to the segment more caudal to the warm stimulus, whereas perceived cold during the TGI decreased compared with the opposite spatial arrangement. This suggests that the perception of TGI is enhanced when cold afferents are projected to spinal segments positioned caudally in relation to those receiving warm afferents. Our results indicate distinct interaction of sensory pathways based on the segmental arrangement of afferent fibres and are consistent with current interpretations of the spread and integration of thermosensory information along the spinal cord.
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Frío , Calor , Ilusiones , Médula Espinal , Sensación Térmica , Humanos , Ilusiones/fisiología , Masculino , Femenino , Sensación Térmica/fisiología , Adulto , Calor/efectos adversos , Médula Espinal/fisiología , Adulto Joven , Piel/inervación , Dolor/fisiopatología , Dimensión del Dolor/métodos , Percepción del Dolor/fisiologíaRESUMEN
The namesake pit organ of pit vipers and other temperature-sensing snakes is a remarkable biological thermometer, one that converts infrared light into an electrical signal (Bullock and Diecke 1956). The organ is arranged like a pinhole camera, with a small outward-facing opening covering a pit membrane dense with neuronal projections. This geometry ensures that only light from a narrow angular cone lands on the membrane. By reorienting its head to scan its surroundings, the snake can precisely detect and localise warm-blooded prey even in complete darkness.
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Serpientes , Animales , Serpientes/fisiología , Sensación Térmica/fisiología , TemperaturaRESUMEN
Thermosensation requires the activation of a unique collection of ion channels and receptors that work in concert to transmit thermal information. It is widely accepted that transient receptor potential melastatin 8 (TRPM8) activation is required for normal cold sensing; however, recent studies have illuminated major roles for other ion channels in this important somatic sensation. In addition to TRPM8, other TRP channels have been reported to contribute to cold transduction mechanisms in diverse sensory neuron populations, with both leak- and voltage-gated channels being identified for their role in the transmission of cold signals. Whether the same channels that contribute to physiological cold sensing also mediate noxious cold signaling remains unclear; however, recent work has found a conserved role for the kainite receptor, GluK2, in noxious cold sensing across species. Additionally, cold-sensing neurons likely engage in functional crosstalk with nociceptors to give rise to cold pain. This Review will provide an update on our understanding of the relationship between various ion channels in the transduction and transmission of cold and highlight areas where further investigation is required.
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Frío , Sensación Térmica , Animales , Humanos , Sensación Térmica/fisiología , Canales Iónicos/metabolismo , Transducción de Señal/fisiología , Canales Catiónicos TRPM/metabolismo , Células Receptoras Sensoriales/fisiología , Células Receptoras Sensoriales/metabolismoRESUMEN
While taste and smell perception have been thoroughly investigated, our understanding of oral somatosensory perception remains limited. Further, assessing and measuring individual differences in oral somatosensory perception pose notable challenges. This review aimed to evaluate the existing methods to assess oral somatosensory perception by examining and comparing the strengths and limitations of each method. The review highlighted the lack of standardized assessment methods and the various procedures within each method. Tactile sensitivity can be assessed using several methods, but each method measures different tactile dimensions. Further investigations are needed to confirm its correlation with texture sensitivity. In addition, measuring a single textural attribute may not provide an overall representation of texture sensitivity. Thermal sensitivity can be evaluated using thermal-change detection or temperature discrimination tests. The chemesthetic sensitivity tests involve either localized or whole-mouth stimulation tests. The choice of an appropriate method for assessing oral somatosensory sensitivity depends on several factors, including the specific research objectives and the target population. Each method has its unique intended purpose, strengths, and limitations, so no universally superior approach exists. To overcome some of the limitations associated with certain methods, the review offers alternative or complementary approaches that could be considered. Researchers can enhance the comprehensive assessment of oral somatosensory sensitivity by carefully selecting and potentially combining methods. In addition, a standardized protocol remains necessary for each method.
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Boca , Percepción del Tacto , Humanos , Percepción del Tacto/fisiología , Boca/fisiología , Individualidad , Percepción del Gusto/fisiología , Tacto/fisiología , Gusto/fisiología , Umbral Sensorial/fisiología , Olfato/fisiología , Sensación Térmica/fisiologíaRESUMEN
Thermoregulation is a fundamental mechanism for maintaining homeostasis in living organisms because temperature affects essentially all biochemical and physiological processes. Effector responses to internal and external temperature cues are critical for achieving effective thermoregulation by controlling heat production and dissipation. Thermoregulation can be classified as physiological, which is observed primarily in higher organisms (homeotherms), and behavioral, which manifests as crucial physiological functions that are conserved across many species. Neuronal pathways for physiological thermoregulation are well-characterized, but those associated with behavioral regulation remain unclear. Thermoreceptors, including Transient Receptor Potential (TRP) channels, play pivotal roles in thermoregulation. Mammals have 11 thermosensitive TRP channels, the functions for which have been elucidated through behavioral studies using knockout mice. Behavioral thermoregulation is also observed in ectotherms such as the fruit fly, Drosophila melanogaster. Studies of Drosophila thermoregulation helped elucidate significant roles for thermoreceptors as well as regulatory actions of membrane lipids in modulating the activity of both thermosensitive TRP channels and thermoregulation. This review provides an overview of thermosensitive TRP channel functions in behavioral thermoregulation based on results of studies involving mice or Drosophila melanogaster.
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Regulación de la Temperatura Corporal , Canales de Potencial de Receptor Transitorio , Animales , Regulación de la Temperatura Corporal/fisiología , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/fisiología , Conducta Animal/fisiología , Sensación Térmica/fisiología , Drosophila melanogaster/fisiología , Ratones , HumanosRESUMEN
Neuromorphic nanoelectronic devices that can emulate the temperature-sensitive dynamics of biological neurons are of great interest for bioinspired robotics and advanced applications such as in silico neuroscience. In this work, we demonstrate the biomimetic thermosensitive properties of two-terminal V3O5 memristive devices and showcase their similarity to the firing characteristics of thermosensitive biological neurons. The temperature-dependent electrical characteristics of V3O5-based memristors are used to understand the spiking response of a simple relaxation oscillator. The temperature-dependent dynamics of these oscillators are then compared with those of biological neurons through numerical simulations of a conductance-based neuron model, the Morris-Lecar neuron model. Finally, we demonstrate a robust neuromorphic thermosensation system inspired by biological thermoreceptors for bioinspired thermal perception and representation. These results not only demonstrate the biorealistic emulative potential of threshold-switching memristors but also establish V3O5 as a functional material for realizing solid-state neurons for neuromorphic computing and sensing applications.
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Neuronas , Temperatura , Neuronas/fisiología , Biomimética/instrumentación , Biomimética/métodos , Modelos Neurológicos , Sensación Térmica/fisiologíaRESUMEN
Understanding the brain response to thermal stimuli is crucial in the sensory experience. This study focuses on non-painful thermal stimuli, which are sensations induced by temperature changes without causing discomfort. These stimuli are transmitted to the central nervous system through specific nerve fibers and are processed in various regions of the brain, including the insular cortex, the prefrontal cortex, and anterior cingulate cortex. Despite the prevalence of studies on painful stimuli, non-painful thermal stimuli have been less explored. This research aims to bridge this gap by investigating brain functional connectivity during the perception of non-painful warm and cold stimuli using electroencephalography (EEG) and the partial directed coherence technique (PDC). Our results demonstrate a clear contrast in the direction of information flow between warm and cold stimuli, particularly in the theta and alpha frequency bands, mainly in frontal and temporal regions. The use of PDC highlights the complexity of brain connectivity during these stimuli and reinforces the existence of different pathways in the brain to process different types of non-painful warm and cold stimuli.
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Encéfalo , Electroencefalografía , Humanos , Electroencefalografía/métodos , Masculino , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Adulto , Femenino , Adulto Joven , Frío , Mapeo Encefálico/métodos , Calor , Dolor , Sensación Térmica/fisiologíaRESUMEN
The purpose of this study was to investigate which climate/heat indices perform best in predicting heat-induced loss of physical work capacity (PWCloss). Integrating data from earlier studies, data from 982 exposures (75 conditions) exercising at a fixed cardiovascular load of 130 beats·min-1, in varying temperatures (15-50°C), humidities (20-80%), solar radiation (0-800 W·m-2), wind (0.2-3.5 m·s-1), and two clothing levels, were used to model the predictive power of ambient temperature, universal thermal climate index (UTCI), wet bulb globe temperature (WBGT), modified physiologically equivalent temperature (mPET), heat index, apparent temperature (AT), and wet bulb temperature (Twb) for the calculation of PWCloss, skin temperature (Tskin) and core-to-skin temperature gradient, and thermal perception (thermal sensation vote, TSV) in the heat. R2, RMSE, and Akaike information criterion were used indicating model performance. Indices not including wind/radiation in their calculation (Ta, heat index, AT, and Twb) struggled to provide consistent predictions across variables. For PWCloss and TSV, UTCI and WBGT had the highest predictive power. For Tskin, and core-to-skin temperature gradient, the physiological models UTCI and mPET worked best in seminude conditions, but clothed, AT, WBGT, and UTCI worked best. For all index predictions, Ta, vapor pressure, and Twb were shown to be the worst heat strain predictors. Although UTCI and WBGT had similar model performance using the full dataset, WBGT did not work appropriately in windy, hot-dry, conditions where WBGT predicted lower strain due to wind, whereas the empirical data, UTCI and mPET indicated that wind in fact increased the overall level of thermal strain. The findings of the current study highlight the advantages of using a physiological model-based index like UTCI when evaluating heat stress in dynamic thermal environments.NEW & NOTEWORTHY There is an urgent need to determine the optimal heat stress metric when forecasting the impact of heat stress on human performance, physiological stress, and perception. We analyzed a wealth of laboratory data, simulating heart rate (HR)-paced work with wide variations in air temperature, humidity, wind speed, solar radiation, and clothing. We conclude that the universal thermal climate index (UTCI) [followed by wet-bulb globe temperature (WBGT)] is the optimal heat index to reliably predict reductions in performance, and elevations in physiological and perceptual stress.
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Regulación de la Temperatura Corporal , Temperatura Corporal , Clima , Calor , Sensación Térmica , Humanos , Sensación Térmica/fisiología , Temperatura Corporal/fisiología , Regulación de la Temperatura Corporal/fisiología , Temperatura Cutánea/fisiología , Humedad , Viento , Masculino , Modelos BiológicosRESUMEN
Metabolic rate has been used in thermophysiological models for predicting the thermal response of humans. However, only a few studies have investigated the association between an individual's trait-like thermal sensitivity and resting energy expenditure (REE), which resulted in inconsistent results. This study aimed to explore the association between REE and perceived thermal sensitivity. The REE of healthy adults was measured using an indirect calorimeter, and perceived thermal intolerance and sensation in the body were evaluated using a self-administered questionnaire. In total, 1567 individuals were included in the analysis (women = 68.9%, age = 41.1â ±â 13.2 years, body mass index = 23.3â ±â 3.3 kg/m2, REE = 1532.1â ±â 362.4 kcal/d). More women had high cold intolerance (31.8%) than men (12.7%), and more men had high heat intolerance (23.6%) than women (16.1%). In contrast, more women experienced both cold (53.8%) and heat (40.6%) sensations in the body than men (cold, 29.1%; heat, 27.9%). After adjusting for age, fat-free mass, and fat mass, lower cold intolerance, higher heat intolerance, and heat sensation were associated with increased REE only in men (cold intolerance, P for trendâ =â .001; heat intolerance, P for trendâ =â .037; heat sensation, Pâ =â .046), whereas cold sensation was associated with decreased REE only in women (Pâ =â .023). These findings suggest a link between the perceived thermal sensitivity and REE levels in healthy individuals.
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Calorimetría Indirecta , Metabolismo Energético , Humanos , Femenino , Masculino , Adulto , Estudios Transversales , Persona de Mediana Edad , Metabolismo Energético/fisiología , Sensación Térmica/fisiología , Metabolismo Basal/fisiología , Factores Sexuales , Calor/efectos adversos , Frío , Índice de Masa CorporalRESUMEN
Plants exposed to incidences of excessive temperatures activate heat-stress responses to cope with the physiological challenge and stimulate long-term acclimation1,2. The mechanism that senses cellular temperature for inducing thermotolerance is still unclear3. Here we show that TWA1 is a temperature-sensing transcriptional co-regulator that is needed for basal and acquired thermotolerance in Arabidopsis thaliana. At elevated temperatures, TWA1 changes its conformation and allows physical interaction with JASMONATE-ASSOCIATED MYC-LIKE (JAM) transcription factors and TOPLESS (TPL) and TOPLESS-RELATED (TPR) proteins for repressor complex assembly. TWA1 is a predicted intrinsically disordered protein that has a key thermosensory role functioning through an amino-terminal highly variable region. At elevated temperatures, TWA1 accumulates in nuclear subdomains, and physical interactions with JAM2 and TPL appear to be restricted to these nuclear subdomains. The transcriptional upregulation of the heat shock transcription factor A2 (HSFA2) and heat shock proteins depended on TWA1, and TWA1 orthologues provided different temperature thresholds, consistent with the sensor function in early signalling of heat stress. The identification of the plant thermosensors offers a molecular tool for adjusting thermal acclimation responses of crops by breeding and biotechnology, and a sensitive temperature switch for thermogenetics.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas Intrínsecamente Desordenadas , Temperatura , Sensación Térmica , Termotolerancia , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Núcleo Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción del Choque Térmico/metabolismo , Factores de Transcripción del Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética , Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas Represoras/metabolismo , Sensación Térmica/genética , Sensación Térmica/fisiología , Termotolerancia/genética , Termotolerancia/fisiología , Factores de Transcripción/metabolismo , Transducción de SeñalRESUMEN
Urban outdoor space has a very important impact on the quality of people's outdoor activities, which has influenced people's health and moods. Its influence is the result of the combined action of various factors. Thermal and air quality environment are important factors affecting the overall comfort of the urban outdoor space. At present, there are few research on interaction with thermal and air quality environment. Therefore, a meteorological measurement and questionnaire survey have been conducted in a representative open space in a campus in Xi'an, China. The following are the research results:(1) Mean physiological equivalent temperature (MPET) is a significant factor affecting thermal sensation vote (TSV) and thermal comfort vote (TCV). PM2.5 has no significant effect on thermal comfort vote (TCV), but it is a considerable factor affecting thermal sensation vote (TSV) when 10.2°C ≤ MPET<21°C (P = 0.023 *). (2) PM2.5 is a significant factor affecting air quality vote (AQV) and breathing comfort vote (BCV).Mean physiological equivalent temperature (MPET) has no significant impact on air quality vote (AQV), but it is a considerable factor affecting breathing comfort vote (BCV) when 10.2°C ≤ MPET<21°C (P = 0.01 **). (3) Mean physiological equivalent temperature (MPET) is a significant factor affecting overall comfort vote (OCV), but PM2.5 is not. In general, When 10.2°C ≤ MPET<21°C (-0.5 < -0.37 ≤ TCV ≤ 0.12 <0.5), the interaction between thermal and PM2.5 environment is significant on thermal sensation vote (TSV) and breathing comfort vote (BCV). This study can provide experimental support for the field of multi-factor interaction, which has shown that improving the thermal environment can better breathing comfort, while reducing PM2.5 concentration can promote thermal comfort. And can also provide reference for the study of human subjective comfort in urban outdoor space in the same latitude of the world.
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Material Particulado , China , Humanos , Proyectos Piloto , Material Particulado/análisis , Contaminación del Aire/análisis , Sensación Térmica/fisiología , Encuestas y Cuestionarios , Contaminantes Atmosféricos/análisis , Ciudades , Temperatura , Masculino , Femenino , Frío , AdultoRESUMEN
Recent insights reveal the significant role of TRPV3 in warmth sensation. A novel finding elucidated how thermosensation is affected by TRPV3 membrane abundance that is modulated by the transmembrane protein TMEM79. TRPV3 is a warmth-sensitive ion channel predominantly expressed in epithelial cells, particularly skin keratinocytes. Multiple studies investigated the roles of TRPV3 in cutaneous physiology and pathophysiology. TRPV3 activation by innocuous warm temperatures in keratinocytes highlights its significance in temperature sensation, but whether TRPV3 directly contributes to warmth sensations in vivo remains controversial. This review explores the electrophysiological and structural properties of TRPV3 and how modulators affect its intricate regulatory mechanisms. Moreover, we discuss the multifaceted involvement of TRPV3 in skin physiology and pathology, including barrier formation, hair growth, inflammation, and itching. Finally, we examine the potential of TRPV3 as a therapeutic target for skin diseases and highlight its diverse role in maintaining skin homeostasis.
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Homeostasis , Queratinocitos , Piel , Canales Catiónicos TRPV , Canales Catiónicos TRPV/metabolismo , Humanos , Animales , Piel/metabolismo , Queratinocitos/metabolismo , Sensación Térmica/fisiología , Enfermedades de la Piel/metabolismo , Enfermedades de la Piel/tratamiento farmacológicoRESUMEN
Objectives. This study explores the effects of temperature steps on thermal responses to understand abrupt temperature shifts faced by heat-exposed workers during winter. Methods. Three temperature step changes with three phases (S20: 20-40-20 °C, S30: 10-40-10 °C, S40: 0-40-0 °C) were conducted. Phase 1 took 30 min, phase 2 took 60 min and phase 3 took 40 min. Eleven participants remained sedentary throughout the experiment, and physiological responses, thermal perception and self-reported health symptoms were recorded. Results. In temperature up steps, steady skin temperature and sweating onset were delayed, and heart rate dropped by 10 bpm from S20 to S40. In temperature down steps to cold conditions, individuals transitioned from thermal comfort to discomfort and eventually cold strain. Blood pressure increased in temperature down steps, correlating with temperature step magnitudes. Thermal responses to temperature steps of equal magnitude but opposite directions were asymmetries, which weakened as step magnitude increased. Thermal perceptions responded faster than physiological changes after temperature steps, while self-reported health symptoms lagged behind physiological responses. Conclusions. These findings contribute to expanding basic data to understand the effects of temperature step magnitude and direction.