INFLUENCE OF AMBIENT TEMPERATURE ON CENTRAL AND PERIPHERAL IMPEDANCE MEASUREMENTS OF THE HUMAN BODY

2011 ◽  
Vol 10 (4) ◽  
pp. 511-517 ◽  
Author(s):  
Calin Corciova ◽  
Radu Ciorap ◽  
Dan Zaharia ◽  
Alexandru Salceanu
Keyword(s):  
Ambient Temperature ◽  
Human Body ◽  
Impedance Measurements

scholarly journals Impact of SiO2 Particles in Polyethylene Textile Membrane for Indoor Personal Heating

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1968
Author(s):  
Mohamed Boutghatin ◽  
Salim Assaf ◽  
Yan Pennec ◽  
Michèle Carette ◽  
Vincent Thomy ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Ambient Temperature ◽  
Human Body ◽  
Synthetic Polymer ◽  
Radiative Heating ◽  
Submicron Particles ◽  
Thermal Heating ◽  
Mid Infrared ◽  
Transmission Properties ◽  
Common Strategy

Keeping the human body in a thermal comfort state inside a room has become a challenge in recent years. While the most common strategy is to heat buildings, it requires a lot of energy. Reducing this energy consumption will have positive impacts, both economically and environmentally. We propose here to act directly on the personal thermal heating of the human body, by modulating the absorption and transmission properties of a synthetic polymer membrane in the mid-infrared (MIR). We show numerically that 5% SiO2 submicron particles inserted in polyethylene (PE) and nanoporous polyethylene (nanoPE) membranes increase the radiative heating of the membrane, reducing the required ambient temperature of a room by more than 1.1 °C. The proposed membrane can be flexible enough to be easily integrated into conventional textiles.

scholarly journals Fermentation of Soybean Seeds Using Rhizopus oligosporus for Tempeh Production and Standardization Based on Isoflavones Content

2021 ◽  
Author(s):  
Yohanes Dwiatmaka ◽  
Endang Lukitaningsih ◽  
Nunung Yuniarti ◽  
Subagus Wahyuono
Keyword(s):  
Ambient Temperature ◽  
Human Body ◽  
Room Temperature ◽  
Soybean Seeds ◽  
Traditional Food ◽  
Rhizopus Oligosporus ◽  
C 30 ◽  
Air Circulation ◽  
Aglycone Isoflavones ◽  
Condition B

Tempeh is an Indonesian traditional food, made from white soybean seeds by fermentation with Rhizopus mold. Soybean seeds content high isoflavone glycosides. Isoflavones can act as phytoestrogen, antioxidant and improves memory. Isoflavone glycosides are poorly absorbed in the human body, but the aglycone isoflavones absorbed quickly. Rhizopus mold hydrolize isoflavone glycosides to be aglycone isoflavones during tempeh production. This research was aimed to know the best room temperature and time of fermentation for making soybean tempeh with high content of isoflavones. After rinsing and boiling, the soybean seeds than fermented with Rhizopus oligosporus. Three conditions were applied: (a) ambient temperature (27-32oC) without air circulation, (b) 27±0.5 oC, and (c) 30±0.5 oC both with air circulations. Inner temperature of tempeh was recorded hourly. Total isoflavones were measured with UV spectrophotometer every 6 hours. Based on this study, fermentation at condition a caused the tempeh too hot and rotted quickly. Fermentation at condition b and c produced tempeh with good quality. Tempeh ripening was reached between 31-32 hours with inner temperature 32-33 oC. Fermentation for 72 hours at condition b was chosen because its high total isoflavones content (0.089% w/w), but decrease about 20% compare to soybean seeds (0.112% w/w).

Effects of solar radiation on thermal sensation and physical fatigue of the human body under heavy-load exercise

2020 ◽  
pp. 1420326X2097473
Author(s):  
Yongqiang Xiao ◽  
Yaping Gao ◽  
Yi Wang ◽  
Xiaojing Meng
Keyword(s):  
Blood Pressure ◽  
Solar Radiation ◽  
Ambient Temperature ◽  
Human Body ◽  
Field Experiments ◽  
Physiological Stress ◽  
Thermal Sensation ◽  
Heavy Load ◽  
Solar Radiation Intensity ◽  
Significant Difference

Solar radiation intensity affects both subjective reactions and physiological functions, especially for people who exercise heavily. Field experiments including a questionnaire survey at various ambient temperatures were performed; outdoor activities under shading (irradiance I =  50 ± 20 W/m2) and non-shading ( I =  700 ± 50 W/m2) conditions during summer in Xi'an were recorded. The results of questionnaires indicated that when the human body reached an extremely hot state, the corresponding environmental temperature was 3.7 °C lower under the non-shading condition, and the range of actual acceptable temperatures was narrower. In terms of thermal sensation, there was a significant difference for people who exercise heavily and those who do not. The results also showed that the curve of fatigue sensation exhibited an inverse Gaussian distribution. Namely, fatigue was promoted under both colder and hotter conditions. Moreover, under non-shading condition, the lowest fatigue incidence was higher, and the corresponding ambient temperature was lower. Changes in objective physiological responses indicated that the solar radiation might cause heat stress. Therefore, when the ambient temperature was higher than 32 °C, physiological stress was higher. Under the same exercise load, the blood pressure was higher under the non-shading condition and systolic blood pressure increased with ambient temperature.

In vivo impedance measurements on nerves and surrounding skeletal muscles in rats and human body

2002 ◽  
Vol 40 (3) ◽  
pp. 323-326 ◽  
Author(s):  
E. Prokhorov ◽  
F. Llamas ◽  
E. Morales-Sánchez ◽  
J. González-Hernández ◽  
A. Prokhorov
Keyword(s):  
Human Body ◽  
Skeletal Muscles ◽  
Impedance Measurements

scholarly journals A revised method to predict skin’s thermal resistance

2018 ◽  
Vol 22 (4) ◽  
pp. 1795-1802
Author(s):  
Lijuan Wang ◽  
Ding Chong ◽  
Yuhui Di ◽  
Hui Yi
Keyword(s):  
Heat Flux ◽  
High Temperature ◽  
Low Temperature ◽  
Thermal Resistance ◽  
Ambient Temperature ◽  
Skin Temperature ◽  
Heat Loss ◽  
Human Body ◽  
New Formula ◽  
Sweat Evaporation

Human body can adjust heat loss by vasoconstriction, vasodilatation, and other methods. The purpose of this research is to investigate whether the thermal resistance of skin reflects vasoconstriction and vasodilatation. For this aim, the ambient temperature was controlled as 18.1, 21.6, 24.9, 27, and 30.5?C, respectively. In each temperature, the skin temperature and heat flux in the forearm were recorded. Based on tested data, the thermal resistance was calculated by a common method. The results showed that the thermal resistance at low temperature was less than that at high temperature, which was contrary to the rule of vasoconstriction and vasodilatation. So a new formula for thermal resistance was presented based on skin diffusion, sweat evaporation, and mass transformation. The results showed that the new method could predict vasoconstriction and vasodilatation. The revised equation is a useful index for physiological thermoregulation.

scholarly journals Fermentation of Soybean Seeds Using Rhizopus oligosporus for Tempeh Production and Standardization Based on Isoflavones Content

2021 ◽  
Author(s):  
Yohanes Dwiatmaka ◽  
Endang Lukitaningsih ◽  
Nunung Yuniarti ◽  
Subagus Wahyuono
Keyword(s):  
Ambient Temperature ◽  
Human Body ◽  
Room Temperature ◽  
Soybean Seeds ◽  
Traditional Food ◽  
Rhizopus Oligosporus ◽  
C 30 ◽  
Air Circulation ◽  
Aglycone Isoflavones ◽  
Condition B

Tempeh is an Indonesian traditional food, made from white soybean seeds by fermentation with Rhizopus mold. Soybean seeds content high isoflavone glycosides. Isoflavones can act as phytoestrogen, antioxidant and improves memory. Isoflavone glycosides are poorly absorbed in the human body, but the aglycone isoflavones absorbed quickly. Rhizopus mold hydrolize isoflavone glycosides to be aglycone isoflavones during tempeh production. This research was aimed to know the best room temperature and time of fermentation for making soybean tempeh with high content of isoflavones. After rinsing and boiling, the soybean seeds than fermented with Rhizopus oligosporus. Three conditions were applied: (a) ambient temperature (27-32oC) without air circulation, (b) 27±0.5 oC, and (c) 30±0.5 oC both with air circulations. Inner temperature of tempeh was recorded hourly. Total isoflavones were measured with UV spectrophotometer every 6 hours. Based on this study, fermentation at (a) condition caused the tempeh too hot and rotted quickly. Fermentation at (b) and (c) conditions produced tempeh with good quality. Tempeh ripening was reached between 32-32 hours with inner temperature 32-33oC. Fermentation for 72 hours at condition (b) was chosen because its high total isoflavones content (0.089% w/w), but decrease about 20% compare to soybean seeds (0.112% w/w).

Assessment of fat-free mass using bioelectrical impedance measurements of the human body

1985 ◽  
Vol 41 (4) ◽  
pp. 810-817 ◽  
Author(s):  
H C Lukaski ◽  
P E Johnson ◽  
W W Bolonchuk ◽  
G I Lykken
Keyword(s):  
Human Body ◽  
Bioelectrical Impedance ◽  
Fat Free Mass ◽  
Impedance Measurements

Theoretical Performance Characteristics of Wearable Thermoelectric Generators

2010 ◽  
Vol 74 ◽  
pp. 9-14 ◽  
Author(s):  
Vladimir Leonov
Keyword(s):  
Ambient Temperature ◽  
Human Body ◽  
Environmental Conditions ◽  
Thermoelectric Generator ◽  
Photovoltaic Cells ◽  
Performance Characteristics ◽  
Thermoelectric Generators ◽  
Heat Generator ◽  
Theoretical Performance

The theory of thermal matching of a thermoelectric generator with the environment has been applied in this work to a wearable thermoelectric generator. This enabled evaluation of its top performance characteristics in typical environmental conditions. To correctly perform the modeling, the relevant properties of the human body as a heat generator for a small-size thermoelectric generator have been studied and presented in the paper as well. The results have been practically validated in different wearable thermoelectric generators. In particular, a power over 1 mW per square centimeter of the skin has been practically demonstrated on a walking person at ambient temperature of –2 °C. The comparison with wearable photovoltaic cells shows that in typical situations thermoelectric generators provide at least ten times more power.

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