Body Temperature and Firefighter Ensemble Temperatures During Exercise and Exposure to Moderate Warm, and Hot Air Temperatures

2001 ◽  
Author(s):  
R. D. Hagan ◽  
Gretchen K. Vurbeff ◽  
Jay H. Heaney ◽  
James A. Hodgdon
Keyword(s):  
Body Temperature ◽  
Hot Air ◽  
Air Temperatures

scholarly journals Comparative Study of Hot Air Drying and Microwave Drying for Dewatered Sludge

2021 ◽  
Author(s):  
Wittawat Wulyapash ◽  
Awassada Phongphiphat ◽  
Sirintornthep Towprayoon
Keyword(s):  
Microwave Power ◽  
Specific Energy Consumption ◽  
Microwave Drying ◽  
Drying Methods ◽  
Drying Time ◽  
Hot Air ◽  
Air Temperatures ◽  
Dewatered Sludge ◽  
Dried Sludge ◽  
Seafood Processing

Abstract Large amounts of sludge are generated from wastewater treatment in seafood processing industries. Most of the dewatered sludge in Thailand is not utilized and disposed by landfilling. The dried sludge utilization as refuse-derived fuel (RDF) is an alternative solution due to the gross calorific value (GCV), which is greater than 21.9 MJ/kg. However, the key obstacle is its high moisture content of 87.4% (wet basis). Therefore, drying methods using hot air and microwave techniques were investigated for preparing dried sludge. The effects of hot air temperatures (100-150 °C) and microwave power levels (100-800 W) were compared on drying kinetics, specific energy consumption (SEC), and characteristics of the dried products. The results showed that drying times were decreased by increasing the hot air temperatures. In the same way, the increase in microwave power levels decreased the drying time. The application of microwaves contributed to reducing the drying time by more than 46% compared to the hot air. The reduction of drying times resulted in the saving SEC. The GCV of the dried sludge decreased with the decrease in the volatile matter (VM) due to the high component of VM as 79.5-80.3% (dry ash-free basis). The sludge dried by the microwaves showed a lower GCV than the hot air products. However, dried sludges still had high GCV (≥ 20.8 MJ/kg). Furthermore, the minimal variation of the product characteristics demonstrated that the microwave technique could be applied as an alternative drying method with a rapid process compared to the conventional hot air technique.

Thermal influence of sunshine and clothing on men walking in humid heat

1962 ◽  
Vol 17 (2) ◽  
pp. 311-316 ◽  
Author(s):  
F. N. Craig ◽  
E. G. Cummings
Keyword(s):  
Body Temperature ◽  
Temperature Gradient ◽  
Air Temperature ◽  
Indoor Air ◽  
Physiological Strain ◽  
Mean Body Temperature ◽  
Clothing Insulation ◽  
Air Temperatures ◽  
Rate Of Increase ◽  
Thermal Influence

For two men walking on a treadmill and wearing two layers of permeable clothing, the same physiological strain measured by the rate of increase in mean body temperature could be produced a) next to a building outdoors in the sunshine with an average air temperature of 85 F and humidity of 20 mm Hg and b) indoors with the same humidity and an air temperature 10 F higher. Under these conditions, the underwear was mainly wet with sweat and the outer layer was mainly dry. In comparable indoor tests on a third subject, the temperature of the underwear approached equilibrium 1 or 2 F lower than the temperature of the skin at air temperatures of 85 and 115 F. The error in calculating clothing insulation introduced by assuming the clothing to be dry is determined by the size and direction of the temperature gradient between skin and air. Adding 10 F to the indoor air temperature does not duplicate all the effects of sunshine. Submitted on September 15, 1961

Physiological reactions of Caucasian and Bantu males in acute exposure to cold

1964 ◽  
Vol 19 (4) ◽  
pp. 583-592 ◽  
Author(s):  
C. H. Wyndham ◽  
J. S. Ward ◽  
N. B. Strydom ◽  
J. F. Morrison ◽  
C. G. Williams ◽  
...  
Keyword(s):  
Body Temperature ◽  
Ethnic Differences ◽  
Metabolic Response ◽  
Climatic Chamber ◽  
Air Temperatures ◽  
Metabolic Reactions ◽  
The Difference ◽  
Physiological Reactions ◽  
Average Skin ◽  
Skin Temperatures

Eleven men per sample of Caucasian and Bantu males were exposed for 2 hr in a climatic chamber at various air temperatures ranging from 5 to 27 C, and a wind velocity of 80–100 ft/min. When expressed per square meter surface area the metabolism of the Bantu was greater in the range above 18 C and below 6 C. Average skin temperatures were similar for both groups, but between 27 and 17 C the toe and finger temperatures of the Caucasians were significantly higher than that of the Bantu—the difference at 27 C being 5 C for the fingers and 3.6 C for the toes. Rectal temperatures of both groups were similar between 27 and 17 C. With the rectal temperatures at 27 C air temperature as the criterion, it was found that as the air temperatures decreased below the 27–17 C range the rectal temperatures of the Bantu fell linearly, while the rectal temperatures of the Caucasians rose steadily. There is no doubt that in certain ranges of air temperatures there are significant differences between the cold reactions of Caucasians and the Bantu. cold adaptation; ethnic differences in response to cold; metabolic and body temperature reactions to cold; metabolic response to body temperature; metabolic reactions of ethnic groups Submitted on July 15, 1963

Sweating in cattle. IV. Control of sweat glands secretion

1959 ◽  
Vol 52 (1) ◽  
pp. 66-71 ◽  
Author(s):  
G. C. Taneja
Keyword(s):  
Nervous System ◽  
Body Temperature ◽  
Sympathetic Nervous System ◽  
Sweat Glands ◽  
Appreciable Effect ◽  
Air Temperatures ◽  
Before And After ◽  
Sympathetic Nervous ◽  
Cutaneous Evaporation ◽  
The University

Two calves (Aberdeen Angus and American Brahman) were used exposed to different combinations of wet- and dry-bulb temperatures in a psychromatric chamber at the Physiology Department of the University of Queensland. These animals were 7–8 months old when first exposed to heat.Effect of various drugs affecting the sympathetic nervous system (adrenaline, noradrenaline, Dibenamine, Priscol, atropine and acetylcholine) on the rate of cutaneous evaporation in calves was tested. Cutaneous evaporation was measured by means of a capsule before and after the administration of these drugs.Cutaneous evaporation increased with the introduction of adrenaline and was suppressed by the administration of Dibenamine. Noradrenaline and Priscol had no appreciable effect. Acetylcholine failed to stimulate sweating and atropine did not block the sweat glands.Sweat glands of cattle were, therefore, found to be functional and their innervation adrenergic. Cattle use sweat to prevent body temperature from rising, yet the amount of sweat secreted is not large enough to allow cattle to maintain thermoneutrality at high air temperatures.

scholarly journals Controlled thawing of foods

2000 ◽  
Vol 18 (No. 5) ◽  
pp. 194-200 ◽  
Author(s):  
K. Hoke ◽  
L. Klíma ◽  
R. Grée ◽  
M. Houška
Keyword(s):  
Power Level ◽  
Point Of View ◽  
Hot Water ◽  
Similar Process ◽  
Hot Air ◽  
Air Temperatures ◽  
The Mean ◽  
Level 1 ◽  
The Times ◽  
Mean Time

The various ways of thawing of model food made for comparison of these processes from point of view of duration. The experiments were conducted under condition that the surface temperature of the thawed food did not overcome 15°C. Shortest mean time of thawing was achieved for vacuum-steam thawing. Regarding to the regime chosen the time of thawing varied between 18.4–29 min. The similar process of vacuum thawing with steam generated from hot water placed below the food was also successful. For this process the mean time of thawing was predicted between 30.5 and 35 min. If the starting temperature of the water was below the boiling point at vacuum level in the chamber the time of thawing was much longer (about 49 min). For hot air thawing we have tested two regimes with temperature of air 50 and 70°C. For both air temperatures the times of thawing were similar being 52.1 and 53.6 min, respectively. Microwave thawing was depending on the power of microwave oven. The time of thawing was achieved 28.9 min at power level 1, at power level “thawing” the process duration was 34.4 min.

Body temperature dynamics of the red squirrel (Tamiasciurus hudsonicus): adaptations for energy conservation

1979 ◽  
Vol 57 (7) ◽  
pp. 1349-1354 ◽  
Author(s):  
Ronald W. Pauls
Keyword(s):  
Body Temperature ◽  
Motor Activity ◽  
Energy Conservation ◽  
Outdoor Environment ◽  
Tamiasciurus Hudsonicus ◽  
Rapid Decline ◽  
Red Squirrel ◽  
Red Squirrels ◽  
Air Temperatures ◽  
Temperature Dynamics

Abdominal temperatures (Tb) of two captive female red squirrels (Tamiasciurus hudsonicus) in a natural outdoor environment were monitored by radiotelemetry at air temperatures (Ta) from −33 to 28 °C. Abdominal temperature ranged from 35.9 to 41.4 °C with values usually less than 39 °C when an animal was in the nest and greater than 39 °C when outside. An increase of Tb to about 39 °C usually occurred before an animal left the nest. In the nest Tb was positively correlated with Ta. Outside the nest there was a weak positive correlation at Ta less than 15 °C and a stronger negative correlation at higher Ta. During subnivean activity a rapid decline in Tb usually occurred. It is suggested that in the nest a low Tb is adaptive in that it results in energy conservation while a higher Tb is required outside the nest for rapid and coordinated motor activity.

Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude II. Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes to the diurnal fluctuation in ambient temperature during the hottest part of the year

1960 ◽  
Vol 55 (3) ◽  
pp. 295-302 ◽  
Author(s):  
R. B. Symington
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Skin Temperature ◽  
Skin Surface ◽  
Diurnal Fluctuation ◽  
Body Temperatures ◽  
Solar Insolation ◽  
Air Temperatures ◽  
Insensible Perspiration ◽  
Artificial Heat

Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes of three breeds to the diurnal fluctuation in ambient temperature were recorded in the presence and absence of drinking water during the hottest part of the Rhodesian year.1. At 7.0 a.m. body temperatures were: Merino 102·8° F.; Persian 102·2° F. and Native 101·5° F. Between 7·0 a.m. and 1·0 p.m. body temperature rose almost equally in Persians and Natives and fell slightly in Merinos. Change in body temperature between 7.0 a.m. and 1.0 p.m. was not affected significantly by availability of water nor age of ewe, but varied with type of thermal burden (i.e. solar insolation only v. solar insolation plus artificial heat) when water was not available. Although air temperature fell towards late afternoon body temperature of Merinos and Natives rose appreciably, that of Persians only slightly.2. At 7·0 a.m. respiratory rates were (cyc./min.): Merino 59·6; Persian 43·0; Native 29·9. Increase in rate of respiration was the main thermolytic mechanism in all breeds. Merinos had a lower threshold of respiratory response to rising ambient temperature than either hair breed but increase in rate of respiration between 7.0 a.m. and 1.0 p.m. did not differ significantly with breed or age.3. No breed appeared to use the peripheral blood system in thermoregulation. Cardio-frequency, as a measure of this blood flow, remained almost constant with a slight tendency to fall with rise in ambient temperature.4. In all breeds skin temperature was related to ambient and body temperatures; consequently the diurnal fluctuation in skin temperature differed in wool and hair breeds. When thermal burden was greatest Merino skin temperature fell, that of hair breeds did not.Except at 11.0 a.m. there was a gradient between rectal, skin and air temperatures. Direct elimination of heat was thus possible for 23 hr. each day.5. In hair breeds moisture secretion depended on insensible perspiration; consequently, rate of moisture secretion changed with body and air temperatures. In Merinos moisture for skin surface evaporation was provided by sensible and insensible perspiration. Natives may be able to sweat at temperatures higher than those recorded but it is unlikely Persians have a sweating mechanism.6. In all breeds coat temperature was related closely to ambient temperature and changes in solar conditions evoked immediate response in coat temperature. Merino fleece apparently stabilized skin temperature whereas Persian and Native hair did not.

Risk factors affecting escape behavior by the desert iguana, Dipsosaurus dorsalis: speed and directness of predator approach, degree of cover, direction of turning by a predator, and temperature

2003 ◽  
Vol 81 (6) ◽  
pp. 979-984 ◽  
Author(s):  
W E Cooper Jr.
Keyword(s):  
Risk Factors ◽  
Body Temperature ◽  
Escape Behavior ◽  
Primary Response ◽  
Single Individual ◽  
Factors Affecting ◽  
Escape Theory ◽  
Approach Distance ◽  
Dipsosaurus Dorsalis ◽  
Air Temperatures

Escape from predators by desert iguanas (Dipsosaurus dorsalis) conforms to predictions of optimal escape theory based on risk. I simulated an approaching predator to study risk factors. The primary response variable was approach distance (= flight-initiation distance), i.e., the distance between predator and prey when the prey initiates escape. In additional studies, I recorded whether lizards permitted me to approach close enough to noose them (an indicator of wariness) and the method of escape. Approach distance was greater when the predator approached rapidly than slowly and directly than indirectly, and when the predator turned toward the lizard rather than away. It was greater in open than in more densely covered habitats, which may reflect greater risk due to conspicuousness and (or) a greater distance to refuge. Early in the day at lower air temperatures, desert iguanas permitted a closer approach before initiating escape. While basking after emergence from burrows, lizards escaped into burrows; later in the day they fled. Lizards that fled had high body temperatures; a single individual captured immediately after entering a burrow had a lower body temperature. Lizards presumably enter burrows when low body temperature limits the running speed, but burrow use is costly because attainment of the activity temperature is delayed because of time elapsed and the temperature decrease in burrows.

Incubation temperatures of the northern shoveler

1979 ◽  
Vol 57 (5) ◽  
pp. 1052-1056 ◽  
Author(s):  
Alan D. Afton
Keyword(s):  
Regression Analysis ◽  
Body Temperature ◽  
Multiple Regression Analysis ◽  
Cooling Rate ◽  
Breeding Season ◽  
Factors Affecting ◽  
Ground Temperatures ◽  
Air Temperatures ◽  
Temperature Records ◽  
Incubation Temperatures

Egg air cell and nest air temperatures, measured in nests of wild northern shovelers near Delta, Manitoba, Canada, averaged 36.1 and 32.0 °C, respectively. Mean brood patch temperature of one captive incubating hen was 39.5 °C. Body temperature of 16 wild incubating hens averaged 41.1 °C. An egg cooling rate of 0.22 °C/1 °C h−1 was calculated from temperature records of 170 incubation recesses. Factors affecting egg cooling during recesses were investigated using multiple regression analysis. Statements in the literature that incubation by Anatidae begins upon termination of laying are not supported by available data. Incubation by waterfowl, as in passerines, apparently begins gradually during the laying period. Air and ground temperatures, by influencing egg cooling rates during incubation, may have been important ultimate factors determining the breeding range and timing of the breeding season for the northern shoveler.

scholarly journals Changes of total polyphenolics and vitamin C in acerola during storage and spray drying process

2018 ◽  
Vol 17 (03) ◽  
pp. 69-76
Author(s):  
Thien T. Le
Keyword(s):  
Vitamin C ◽  
Spray Drying ◽  
Room Temperature ◽  
Frozen Storage ◽  
Storage Conditions ◽  
Drying Process ◽  
Hot Air ◽  
Air Temperatures ◽  
Significant Difference ◽  
Processing Steps

Acerola fruit is known to have a high vitamin C concentration. Polyphenolics are also natural oxidants occurring in plants. Understanding changes of these components during storage conditions and processing steps become important. Results of this research showed that there was significant difference in vitamin C and total polyphenolic concentration and three popular varieties of acerola fruits from Tien Giang province. Concentrations of both vitamin C and polyphenolics reduced rapidly during storage at room temperature. After three days, vitamin C reduced about 40% whereas total polyphenolics reduced about 70%. The losses at refrigerated temperature after 3 days were less than 15% and less than 30%, for vitamin C and total polyphenolics, respectively. Frozen storage of the fruit maintained quite well vitamin C and polyphenolics. Acerola pomace juice was concentrated before spray drying and, at the same vacuum pressure, temperatures influenced significantly the retention of vitamin C and total polyphenolics. Optimization of spray drying conditioners including inlet hot air temperatures and added ratio of maltodextrin (drying carrier) was also carried out to obtain high recovery of dry matter, total polyphenolics and vitamin C.

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