Determination of body heat storage: how to select the weighting of rectal and skin temperatures for clothed subjects

1996 ◽  
Vol 68 (5) ◽  
pp. 325-336 ◽  
Author(s):  
Yukitoshi Aoyagi ◽  
T. M. McLellan ◽  
Roy J. Shephard
1995 ◽  
Vol 27 (Supplement) ◽  
pp. S107
Author(s):  
Yukitoshi Aoyagi ◽  
Tom M. McLellan ◽  
Roy J. Shephard

1976 ◽  
Vol 40 (3) ◽  
pp. 384-392 ◽  
Author(s):  
P. Chappuis ◽  
P. Pittet ◽  
E. Jequier

Rate of heat storage (S) was measured by using direct and indirect calorimetry simultaneously in 11 subjects during rest and exercise at three ambient temperatures (Ta of 20, 25, and 30 degrees C), and at two work intensities (40 and 90 W). At rest, the mean value of S was -64.9 W at 20 degrees C, -26.1 W at 25 degrees C, and +9.9 W at 30 degrees C. After 50 min of exercise at 40 or 90 W, S tended toward zero at the three ambient temperatures. This indicates that thermal equilibrium was reached. In addition, at the end of the exercise periods total heat losses (R + C + E) measured at a Ta of 20, 25, and 30 degrees C were similar, i.e., independent of Ta. During the thermal transients and the steady state of exercise, the calorimetric method allows immediate measurement of S to be made, since all the physical terms of the body heat balance equation are determined. The changes in mean body temperature (delta Tb) measured by thermometry showed a delay of 5–10 min when compared with delta Tb measured by calorimetry. Thus, determination of delta Tb by thermometry is not directly applicable during thermal transients, unless the observed delay is taken into account. Our results also support the concept that Tb may be the regulated variable of the thermoregulatory system, since we obtained a very significant and uniform correlation between Esk and delta Tb at the three Ta and the two work intensities which were studied.


2002 ◽  
Vol 80 (8) ◽  
pp. 796-803 ◽  
Author(s):  
Jean-Claude Launay ◽  
Yves Besnard ◽  
Angélique Guinet ◽  
Germain Bessard ◽  
Christian Raphel ◽  
...  

The effects of modafinil on heat thermoregulatory responses were studied in 10 male subjects submitted to a sweating test after taking 200 mg of modafinil or placebo. Sweating tests were performed in a hot climatic chamber (45°C, relative humidity <15%, wind speed = 0.8 m·s–1, duration 1.5 h). Body temperatures (rectal (Tre) and 10 skin temperatures (Tsk)), sweat rate, and metabolic heat production (Mdot) were studied as well as heart rate (HR). Results showed that modafinil induced at the end of the sweating test higher body temperatures increases (0.50 ± 0.04 versus 0.24 ± 0.05°C (P < 0.01) for deltaTre and 3.64 ± 0.16 versus 3.32 ± 0.16°C (P < 0.05) for deltaTbarsk (mean skin temperature)) and a decrease in sweating rate throughout the heat exposure (P < 0.05) without change in Mdot, leading to a higher body heat storage (P < 0.05). DeltaHR was also increased, especially at the end of the sweating test (17.95 ± 1.49 versus 12.52 ± 1.24 beats/min (P < 0.01)). In conclusion, modafinil induced a slight hyperthermic effect during passive dry heat exposure related to a lower sweat rate, probably by its action on the central nervous system, and this could impair heat tolerance. Key words: modafinil, heat, human, thermoregulation.


1995 ◽  
Vol 71 (2-3) ◽  
pp. 197-206 ◽  
Author(s):  
Yukitoshi Aoyagi ◽  
Tom M. McLellan ◽  
Roy J. Shephard
Keyword(s):  

2020 ◽  
Vol 42 (2) ◽  
pp. 68-75
Author(s):  
V.G. Demchenko ◽  
А.S. Тrubachev ◽  
A.V. Konyk

Worked out methodology of determination of the tensely-deformed state of elements of mobile heat storage of capacity type, that works in the real terms of temperature and power stress on allows to estimate influence of potential energy on resilient deformation that influences on reliability of construction and to give recommendations on planning of tank (capacities) of accumulator. For determination possibly of possible tension of construction of accumulator kinematics maximum terms were certain. As a tank of accumulator shows a soba the difficult geometrical system, the mathematical model of calculation of coefficient of polynomial and decision of task of minimization of functional was improved for determination of tension for Міzеs taking into account the real geometry of equipment. Conducted quantitative estimation of the tensely-deformed state of the union coupling, corps and bottom of thermal accumulator and the resource of work of these constructions is appraised. Thus admissible tension folds 225 МРа.


2018 ◽  
Vol 145 ◽  
pp. 71-79 ◽  
Author(s):  
Sven Kunkel ◽  
Tobias Teumer ◽  
Patrick Dörnhofer ◽  
Kerstin Schlachter ◽  
Yohana Weldeslasie ◽  
...  

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