Integrated cooling (i-Cool) textile of heat conduction and sweat transportation for personal perspiration management

Perspiration evaporation plays an indispensable role in human body heat dissipation. However, conventional textiles tend to focus on sweat removal and pay little attention to the basic thermoregulation function of sweat, showing limited evaporation ability and cooling efficiency in moderate/profuse perspiration scenarios. Here, we propose an integrated cooling (i-Cool) textile with unique functional structure design for personal perspiration management. By integrating heat conductive pathways and water transport channels decently, i-Cool exhibits enhanced evaporation ability and high sweat evaporative cooling efficiency, not merely liquid sweat wicking function. In the steady-state evaporation test, compared to cotton, up to over 100% reduction in water mass gain ratio, and 3 times higher skin power density increment for every unit of sweat evaporation are demonstrated. Besides, i-Cool shows about 3 °C cooling effect with greatly reduced sweat consumption than cotton in the artificial sweating skin test. The practical application feasibility of i-Cool design principles is well validated based on commercial fabrics. Owing to its exceptional personal perspiration management performance, we expect the i-Cool concept can provide promising design guidelines for next-generation perspiration management textiles.

A Finite Element Approach to Evaluate Thermoregulation in the Human Body due to the Effects of Sweat Evaporation during Cooking, Cleaning, and Walking

Sweat evaporation is the principal process of dissipating heat energy in a hot environment and during activities. Sweat loss is significantly affected by the level of energy expenditure, hormones, and the number of sweat glands. The thickness of the skin layer plays a vital role to maintain body temperature. The rate of sweat evaporation varies with ambient temperature and activity level. On increasing both metabolism and ambient temperature, sweat rate loss also increases and controls the body in the thermoregulatory system. The evaporative sweat release rate has a linear behavior. The appropriate physical and physiological parameters that affect thermoregulation have been incorporated into the model. The study presents the temperature distribution in three layers: epidermis, dermis, and subcutaneous tissue (SST) of the human dermal parts during cooking, cleaning, and walking. The solution is obtained by using the finite element method. The results demonstrate that the body mechanism keeps the body in thermoregulation by increasing the sweat evaporation rate exhibited by increasing the ambient temperature and metabolism during strenuous activities.

DESIGN AND CFD ANALYSIS OF CEILING FAN FOR REGULAR ROOM SIZE

Fans are playing a major role around the globe for effective and pocket friendly cooling, especially in the region of Asia where humidity is high. Thermal comfort being one of the most important factors for improvement in working environment for better quality of work. Moving of air around the body helps sweat evaporation and makes body feel comfortable. Mixing of air from top to bottom of the area so as to neutralize the change in temperature is done by fans effectively than any other means. Destratification of air is the biggest problem faced in any enclosed area which can be rectified by using fans. CFD Analysis is performed on the designed ceiling fan to analyze the airflow around the area of interest

The Suitability of Porous Material to Simulate Evaporation in Human Sweating Mechanisms

This study aims to determine the suitable porous material that can simulate human sweat evaporation rate for preliminary thermal comfort assessment. The objective of the study was to identify the relationship of human sweat evaporation rate with porous material evaporation rate. Field experimental has been conducted to measure the evaporation rate of porous material such as red clay, white clay, plaster and human sweat. Then, the correlation analysis was conducted between porous material evaporation rate and human sweat evaporation rate. The collected data were analyzed by using SPSS 20 and Microsoft Excel 2016 tools. Pearson correlation were used as statistical analysis to find the relationship between both variable. The statistical significance level was set at P< 0.01. Based on the findings, human sweat evaporation rate had a moderate correlation with red clay (r = 0.583) and white clay (r = 0.503) with statistically significant but very weak correlation with plaster (r = 0.020). The porous characteristics of red clay and white clay has the capillary effect which is almost like human skin by showing a good correlation between human sweat and porous material evaporation rate. As this is preliminary study, in future more research to be done to obtain higher correlation between porous material and the human body by modifying the material. To minimize heat stress, it would be a step forward in evaluating outdoor thermal comfort and raising awareness of society and government.

2889. Skin Niche Conditions Trigger C. auris to Form Robust Biofilms That Resist Desiccation

Background Emerging pathogen Candida auris, the first fungus to be labeled as a public health threat, causes nosocomial outbreaks of invasive candidiasis with mortality as high as 60%. Little is known about the pathogenesis of this species that has newly arisen in the last 10 years. It is unclear why this species readily colonizes the skin and transmits efficiently in healthcare settings. We considered the possibility that C. auris may proliferate in conditions of the skin niche. Methods We analyzed the growth of C. auris (B11203) in synthetic sweat media that was designed to mimic human axillary sweat. We included C. albicans SC5314 as a comparison. To simulate sweat evaporation, we examined fungal growth in sweat media that had been concentrated up to 2.5-fold. We utilized OD600 readings to quantify planktonic and biofilm growth. Biofilm architecture was assessed by scanning electron microscopy. To determine the resilience of biofilms, biofilm viability was assessed by viable burden following desiccation. Results In the various concentrations of sweat media, C. auris formed biofilms that were 3.5- to 5-fold greater that those observed for C. albicans (A). In contrast, C. auris biofilms formed in RPMI-MOPS were approximately half the density of the C. albicans biofilms. During planktonic growth in synthetic sweat media, C. auris and C. albicans replicated similarly, including in media that had been concentrated 2.5-fold. This suggests that the various media conditions differently trigger biofilm formation for the two species. The C. auris biofilm formed in sweat media was approximately 100-fold more resistant to 1 week of desiccation (B). Conclusion Skin niche conditions trigger C. auris to form resilient biofilms that resist desiccation. We propose that this unique characteristic may account for the propensity of this species to colonize the skin and for its capacity to persist on the surface of contaminated medical devices. Disclosures All Authors: No reported Disclosures.

Kajian Eksperimen Pengaruh Lingkungan Panas Terhadap Suhu Kulit Manusia Menggunakan Fast Response Temperature Probe PS-2135 dan Temperature Array PS-2157

Fisika merupakan ilmu alam yang saling berkaitan dengan ilmu lainnya. Salah satu keterkaitannya mempelajari sistem adaptasi tubuh manusia terhadap perubahan suhu. Suhu kulit adalah faktor mendasar dalam pertukaran panas antara tubuh dan lingkungannya. Tingkat suhu kulit secara langsung mempengaruhi transfer energi oleh konveksi dan radiasi dan juga memengaruhi kehilangan panas dari penguapan keringat. Dalam studi eksperimental ini, nilai perubahan suhu kulit dikumpulkan menggunakan Fast Response Temperature Probe PS-2135 dan Temperature Array PS-2157. Tujuan dari studi ini adalah untuk menyelidiki efek dari lingkungan panas pada respon fisiologis suhu kulit tubuhPhysics is a natural science that is interrelated with other sciences. One connection is studying the human body's adaptation system to temperature changes. Skin temperature is a fundamental factor in heat exchanges between the body and its environment. The level of skin temperature directly affects the energy transfer by convection and radiation and also influences heat losses from sweat evaporation. In this experimental study, the skin temperature changes values are collected using Fast Response Temperature Probe PS-2135 and Temperature Array PS-2157. The purpose of this study was to investigate the effects of warm environmental on physiological responses of body skin temperaturePhysics is a natural science that is interrelated with other sciences. One connection is studying the human body's adaptation system to temperature changes. Skin temperature is a fundamental factor in heat exchanges between the body and its environment. The level of skin temperature directly affects the energy transfer by convection and radiation and also influences heat losses from sweat evaporation. In this experimental study, the skin temperature changes values are collected using Fast Response Temperature Probe PS-2135 and Temperature Array PS-2157. The purpose of this study was to investigate the effects of warm environmental on physiological responses of body skin temperature