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

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Dev Chandra Shrestha ◽  
Saraswati Acharya ◽  
Dil Bahadur Gurung
Keyword(s):  
Finite Element ◽  
Ambient Temperature ◽  
Sweat Rate ◽  
Subcutaneous Tissue ◽  
Skin Layer ◽  
Vital Role ◽  
The Body ◽  
Activity Level ◽  
Sweat Glands ◽  
Sweat Evaporation

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.

TEMPERATURE DISTRIBUTION AND THERMAL DAMAGE OF PERIPHERAL TISSUE IN HUMAN LIMBS DURING HEAT STRESS: A MATHEMATICAL MODEL

2016 ◽  
Vol 16 (05) ◽  
pp. 1650064 ◽  
Author(s):  
MIR AIJAZ ◽  
M. A. KHANDAY
Keyword(s):  
Finite Element ◽  
Temperature Distribution ◽  
Heat Generation ◽  
Thermal Damage ◽  
Subcutaneous Tissue ◽  
The Body ◽  
Bioheat Equation ◽  
Metabolic Heat ◽  
Metabolic Heat Generation ◽  
Living Tissues

The physiological processes taking place in human body are disturbed by the abnormal changes in climate. The changes in environmental temperature are not effective only to compete with thermal stability of the system but also in the development of thermal injuries at the skin surfaces. Therefore, it is of great importance to estimate the temperature distribution and thermal damage in human peripherals at extreme temperatures. In this paper, the epidermis, dermis and subcutaneous tissue were modeled as uniform elements with distinct thermal properties. The bioheat equation with appropriate boundary conditions has been used to estimate the temperature profiles at the nodal points of the skin and subcutaneous tissue with variable ambient heat and metabolic activities. The model has been solved by variational finite element method and the results of the changes in temperature distribution of the body and the damage to the exposed living tissues has been interpreted graphically in relation with various atmospheric temperatures and rate of metabolic heat generation. By involving the metabolic heat generation term in bioheat equation and using the finite element approach the results obtained in this paper are more reasonable and appropriate than the results developed by Moritz and Henriques, Diller and Hayes, and Jiang et al.

Comparative Study on Distribution of Sebaceous and Sweat Glands in Skin of Different Domestic Animals

2021 ◽  
Author(s):  
Shweta Raghav ◽  
Varinder Uppal ◽  
Anuradha Gupta
Keyword(s):  
Total Body Weight ◽  
Vital Role ◽  
Hair Follicles ◽  
The Body ◽  
Sweat Glands ◽  
Sebaceous Glands ◽  
Adult Cattle ◽  
Paraffin Block ◽  
The Difference ◽  
Hematoxylin And Eosin Stain

Background: Skin is the largest organ of the body, accounting for 15-20% of the total body weight and acts as a barrier between the external and internal environment and maintain homeostasis.The sweat and sebaceous glands in dermis of skin play vital role in developing the adaptive ability to the heat stress. Besides this, the distribution pattern and number of these glands vary in different animals that may aid in identification of different species.Methods: The study was conducted on abdominal skin of 36 adult cattle, buffalo, horse, goat, pig and dog (six sample of each) collected from abattoir, Veterinary clinics and post-mortem hall of GADVASU, Ludhiana. After collection, the tissues were fixed in 10% neutral buffered formalin and processed for paraffin block preparation. The paraffin sections of 5-6 µm were cut and stained with hematoxylin and eosin stain. Result: The study revealed that the sebaceous glands were multilobular, alveolar glands comprised of several layers of epithelial cells and were associated with hair follicles in all species studied. The number of sebaceous glands/mm2 was significantly higher (p≤0.05) in goat (1.60± 0.11) than in pig (0.44±0.06) whereas sebaceous gland diameter was significantly higher (p≤0.05) in buffalo (109.83±6.14 µm) than in goat (61.16 ±2.42 µm).The sweat glands were of saccular and simple coiled tubular type and most of them were associated with hair follicles. The number of sweat glands/mm2 was the highest in horse (3.10 ± 0.24) and the least in buffalo (0.76 ±0.05). Sweat gland diameter was significantly higher (p≤0.05) maximum in buffalo (123±3.15 µm) and minimum in goat (50.33 ±2.85 µm) and the difference.

scholarly journals The effect of purslane hydroextract and zinc on performance, antioxidant capacity and immunity of broiler chickens during summer conditions

2018 ◽  
Vol 61 (3) ◽  
pp. 365-371
Author(s):  
Rojin Kazemi ◽  
Ardashir Sheikhahmadi ◽  
Ghorbanali Sadeghi
Keyword(s):  
Body Weight ◽  
Ambient Temperature ◽  
Antioxidant Capacity ◽  
Broiler Chickens ◽  
Control Diet ◽  
Basal Diet ◽  
The Body ◽  
Activity Level ◽  
Butylated Hydroxytoluene ◽  
Lactate Dehydrogenase Activity

Abstract. Due to negative effects of high ambient temperature, the present study was conducted to investigate the effects of Portulaca oleracea hydroextract (PHE) and zinc (Zn) on the growth performance and immunity of broiler chickens reared under high summer ambient temperature conditions. A total of 420 day-old male broiler chickens (Ross 308) were randomly allocated to seven dietary treatments each replicated four times with 15 birds per replicate. The basal diet as the control diet was supplemented with 100 mg kg−1 butylated hydroxytoluene (BHT), or 300 and 600 mg kg−1 of PHE, 100 mg kg−1 of zinc and 100 mg kg−1 of zinc plus 300 or 600 mg kg−1 of PHE (ZP300 and ZP600). The result of the present study showed that Zn, PHE and their combination did not alter daily feed intake and feed conversion ratio. Although there was a tendency toward an increase in broiler body weight at 24 and 44 days of age (P=0.059 and P=0.061), the body weight of birds fed the basal diet supplemented with Zn reduced at day 10. The birds fed diets supplemented with BHT or ZP600 showed lower aspartate aminotransferase (ASAT) and lactate dehydrogenase activity at 24 days of age (P<0.05), but it remains lower in the ZP600 group only for ASAT activity level at day 44. The results of the present study suggest that dietary PHE and Zn supplementation partially improved body weight and serum antioxidant capacity, superoxide dismutase activity and antibody titer against sheep red blood cells and Newcastle diseases in the broiler chickens during summer conditions.

Great Increase of Numbers of Virus Particles by Irradiating C3H Mouse Mammary Tumors Transplanted into Male Mice

1972 ◽  
Vol 30 ◽  
pp. 272-273
Author(s):  
P. J. Melnick ◽  
J. W. Cha ◽  
E. Samouhos
Keyword(s):  
Subcutaneous Tissue ◽  
Mammary Tumors ◽  
The Body ◽  
X Ray ◽  
Virus Particles ◽  
Mouse Mammary Tumors ◽  
Transplantable Tumors ◽  
C3h Mice ◽  
Cobalt Radiation ◽  
Enzyme Changes

Spontaneous mammary tumors in females of a high tumor strain of C3H mice were cut into small fragments that were Implanted into the subcutaneous tissue of the back of males of the same strain, where they grew as transplantable tumors. When about Cm. In diameter daily fractional radiation was begun, applied to the tumors, the rest of the body being shielded by a lead shield. Two groups were treated with 150 and 200 r X-ray dally, of half value layer 0.6mm. copper; a third group was treated with 500 r cobalt radiation dally. The primary purpose was to examine the enzyme changes during radiation, with histochemlcal technics.

Iron Metabolism in the Human Body and Setting its Hygienic Limits for Drinking Water. Review. Part 2

2020 ◽  
Vol 99 (5) ◽  
pp. 504-508
Author(s):  
Natalija A. Egorova ◽  
N. V. Kanatnikova
Keyword(s):  
Oxidative Stress ◽  
Drinking Water ◽  
Iron Overload ◽  
Iron Metabolism ◽  
Subcutaneous Tissue ◽  
Allergic Diseases ◽  
The Body ◽  
Urogenital System ◽  
High Iron Content ◽  
Labile Iron Pool

Iron is an assential element for the growth, division, differentiation and functioning of any cell in the body. Iron is virtually important for human and danger at the same time, because with excessive accumulation it causes oxidative stress with formation of highly active oxygen radicals and reactive form of nitrogen that can destroy cell membranes, proteins, nucleic acids, reduce cell viability, with, according to modern concepts, can contribute to the development of many diseases (cardiovascular, rheumatic, gastrointestinal, neurodegenerative, oncological, metabolic and others), and also accelerate the aging process. Part 1 of this review discussed the issues of iron metabolism in human, including its regulation at the cellular and systemic levels, the intake, transport, use, accumulation and export of iron in cells, the role of the labile iron pool in the cytoplasm of cells and plasma non-transferrin bound iron. Data are provided on the causes, frequency and significance of iron overload in the formation of free radicals and the development of oxidative stress. Part 2 of the review provides information on diseases associated with iron overload as well as information on ferroptosis - a new type of iron-dependent regulated cell death. Attention is paid to the works of domestic authors, where it was found that prolonged use of drinking water with a high iron content is unfavorable for the population and leads to an increase in the overall incidence, the development of the diseases of the blood, skin and subcutaneous tissue, musculoskeletal system, digestive system, urogenital system, and allergic diseases. Separate publications are cited on the possibility of a negative effect of iron at concentrations in water of 0.3 mg/l and lower. The material of the review emphasizes the preventive significance of caution attitude to regulating iron in the water in the Russian Federation, where 1/3 of the population uses iron-containing water for drinking, and substantiate the feasibility of establishing a hygienic limit for iron in water not higher than 0.3 mg/l.

scholarly journals The Mechanism of Secretion and Metabolism of Gut-Derived 5-Hydroxytryptamine

2021 ◽  
Vol 22 (15) ◽  
pp. 7931
Author(s):  
Ning Liu ◽  
Shiqiang Sun ◽  
Pengjie Wang ◽  
Yanan Sun ◽  
Qingjuan Hu ◽  
...  
Keyword(s):  
Cell Metabolism ◽  
Circulatory System ◽  
Vital Role ◽  
The Body ◽  
Neuroendocrine Cells ◽  
Intestinal Lumen ◽  
Paracrine Signaling ◽  
Inflammatory Conditions ◽  
Epithelial Development ◽  
Ec Cells

Serotonin, also known as 5-hydroxytryptamine (5-HT), is a metabolite of tryptophan and is reported to modulate the development and neurogenesis of the enteric nervous system, gut motility, secretion, inflammation, sensation, and epithelial development. Approximately 95% of 5-HT in the body is synthesized and secreted by enterochromaffin (EC) cells, the most common type of neuroendocrine cells in the gastrointestinal (GI) tract, through sensing signals from the intestinal lumen and the circulatory system. Gut microbiota, nutrients, and hormones are the main factors that play a vital role in regulating 5-HT secretion by EC cells. Apart from being an important neurotransmitter and a paracrine signaling molecule in the gut, gut-derived 5-HT was also shown to exert other biological functions (in autism and depression) far beyond the gut. Moreover, studies conducted on the regulation of 5-HT in the immune system demonstrated that 5-HT exerts anti-inflammatory and proinflammatory effects on the gut by binding to different receptors under intestinal inflammatory conditions. Understanding the regulatory mechanisms through which 5-HT participates in cell metabolism and physiology can provide potential therapeutic strategies for treating intestinal diseases. Herein, we review recent evidence to recapitulate the mechanisms of synthesis, secretion, regulation, and biofunction of 5-HT to improve the nutrition and health of humans.

scholarly journals Experiments on Energy-Efficient Evaporative Cooling Systems for Poultry Farm Application in Multan (Pakistan)

2021 ◽  
Vol 13 (5) ◽  
pp. 2836
Author(s):  
Khawar Shahzad ◽  
Muhammad Sultan ◽  
Muhammad Bilal ◽  
Hadeed Ashraf ◽  
Muhammad Farooq ◽  
...  
Keyword(s):  
Heat Stress ◽  
Low Cost ◽  
Evaporative Cooling ◽  
Thermal Exposure ◽  
Climatic Conditions ◽  
The Body ◽  
Dew Point ◽  
Sweat Glands ◽  
Cooling Systems ◽  
Humidity Index

Poultry are one of the most vulnerable species of its kind once the temperature-humidity nexus is explored. This is so because the broilers lack sweat glands as compared to humans and undergo panting process to mitigate their latent heat (moisture produced in the body) in the air. As a result, moisture production inside poultry house needs to be maintained to avoid any serious health and welfare complications. Several strategies such as compressor-based air-conditioning systems have been implemented worldwide to attenuate the heat stress in poultry, but these are not economical. Therefore, this study focuses on the development of low-cost and environmentally friendly improved evaporative cooling systems (DEC, IEC, MEC) from the viewpoint of heat stress in poultry houses. Thermodynamic analysis of these systems was carried out for the climatic conditions of Multan, Pakistan. The results appreciably controlled the environmental conditions which showed that for the months of April, May, and June, the decrease in temperature by direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and Maisotsenko-Cycle evaporative cooling (MEC) systems is 7–10 °C, 5–6.5 °C, and 9.5–12 °C, respectively. In case of July, August, and September, the decrease in temperature by DEC, IEC, and MEC systems is 5.5–7 °C, 3.5–4.5 °C, and 7–7.5 °C, respectively. In addition, drop in temperature-humidity index (THI) values by DEC, IEC, and MEC is 3.5–9 °C, 3–7 °C, and 5.5–10 °C, respectively for all months. Optimum temperature and relative humidity conditions are determined for poultry birds and thereby, systems’ performance is thermodynamically evaluated for poultry farms from the viewpoint of THI, temperature-humidity-velocity index (THVI), and thermal exposure time (ET). From the analysis, it is concluded that MEC system performed relatively better than others due to its ability of dew-point cooling and achieved THI threshold limit with reasonable temperature and humidity indexes.

scholarly journals Kidney Inflammation, Injury and Regeneration 2020

2021 ◽  
Vol 22 (11) ◽  
pp. 5589
Author(s):  
Patrick C. Baer ◽  
Benjamin Koch ◽  
Helmut Geiger
Keyword(s):  
Vital Role ◽  
The Body ◽  
Physiological Functions

The kidneys play a vital role in the basic physiological functions of the body [...]

scholarly journals Insect body size changes under future warming projections: a case study of Chironomidae (Insecta: Diptera)

Hydrobiologia ◽  
2021 ◽  
Author(s):  
Rungtip Wonglersak ◽  
Phillip B. Fenberg ◽  
Peter G. Langdon ◽  
Stephen J. Brooks ◽  
Benjamin W. Price
Keyword(s):  
Body Size ◽  
Ambient Temperature ◽  
Wing Length ◽  
The Body ◽  
Mesocosm Experiments ◽  
Future Warming ◽  
Increasing Temperature ◽  
Emergence Date ◽  
Average Body

AbstractChironomids are a useful group for investigating body size responses to warming due to their high local abundance and sensitivity to environmental change. We collected specimens of six species of chironomids every 2 weeks over a 2-year period (2017–2018) from mesocosm experiments using five ponds at ambient temperature and five ponds at 4°C higher than ambient temperature. We investigated (1) wing length responses to temperature within species and between sexes using a regression analysis, (2) interspecific body size responses to test whether the body size of species influences sensitivity to warming, and (3) the correlation between emergence date and wing length. We found a significantly shorter wing length with increasing temperature in both sexes of Procladius crassinervis and Tanytarsus nemorosus, in males of Polypedilum sordens, but no significant relationship in the other three species studied. The average body size of a species affects the magnitude of the temperature-size responses in both sexes, with larger species shrinking disproportionately more with increasing temperature. There was a significant decline in wing length with emergence date across most species studied (excluding Polypedilum nubeculosum and P. sordens), indicating that individuals emerging later in the season tend to be smaller.

scholarly journals Role of Bradykinin Type 2 Receptors in Human Sweat Secretion: Translational Evidence Does Not Support a Functional Relationship

2021 ◽  
Vol 34 (3) ◽  
pp. 162-166
Author(s):  
Thad E. Wilson ◽  
Seetharam Narra ◽  
Kristen Metzler-Wilson ◽  
Artur Schneider ◽  
Kelsey A. Bullens ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Sweat Rate ◽  
Sweat Glands ◽  
Potential Therapeutic Target ◽  
Sweat Secretion ◽  
Hoe 140 ◽  
A Current

Bradykinin increases skin blood flow via a cGMP mechanism but its role in sweating in vivo is unclear. There is a current need to translate cell culture and nonhuman paw pad studies into in vivo human preparations to test for therapeutic viability for disorders affecting sweat glands. Protocol 1: physiological sweating was induced in 10 healthy subjects via perfusing warm (46–48°C) water through a tube-lined suit while bradykinin type 2 receptor (B2R) antagonist (HOE-140; 40 μM) and only the vehicle (lactated Ringer’s) were perfused intradermally via microdialysis. Heat stress increased sweat rate (HOE-140 = +0.79 ± 0.12 and vehicle = +0.64 ± 0.10 mg/cm<sup>2</sup>/min), but no differences were noted with B2R antagonism. Protocol 2: pharmacological sweating was induced in 6 healthy subjects via intradermally perfusing pilocarpine (1.67 mg/mL) followed by the same B2R antagonist approach. Pilocarpine increased sweating (HOE-140 = +0.38 ± 0.16 and vehicle = +0.32 ± 0.12 mg/cm<sup>2</sup>/min); again no differences were observed with B2R antagonism. Last, 5 additional subjects were recruited for various control experiments which identified that a functional dose of HOE-140 was utilized and it was not sudorific during normothermic conditions. These data indicate B2R antagonists do not modulate physiologically or pharmacologically induced eccrine secretion volumes. Thus, B2R agonist/antagonist development as a potential therapeutic target for hypo- and hyperhidrosis appears unwarranted.

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