Circadian variations in the sweating mechanism

1975 ◽  
Vol 39 (2) ◽  
pp. 226-230 ◽  
Author(s):  
J. Timbal ◽  
J. Colin ◽  
C. Boutelier
Keyword(s):  
Body Temperature ◽  
Human Subjects ◽  
Heat Exposure ◽  
The Body ◽  
Circadian Variations ◽  
Mean Body Temperature ◽  
Two Temperatures ◽  
The Difference ◽  
Gains And Losses ◽  
Skin Temperatures

Sweat rates and body temperatures of human subjects were measured at 0200, 1000, and 1800 h during a heat exposure of 90 min. The latent period of sweating was not significantly altered in the evening but significantly shortened during the night. Mean body temperature corresponding to the onset of sweating was nearer to the basal body temperature during the night, while during the day the difference between these two temperatures became larger. This phenomenon seems related to the circadian cycle of vasomotor adjustment, since during the night body conductance was higher than during the day and corresponded to a state of a vasodilatation similar to that observed at the onset of sweating. During the day, this situation was reversed. During steady state, the following changes were observed: sweating rate, night less than morning less than evening; skin temperatures, night less than morning less than evening; and rectal temperature increase, morning less than evening less than night. It is hypothesized that these changes are due to either different metabolic rates or an imbalance between heat gains and losses which preserve the circadian rhythm of the body temperature, even under thermal loads.

The significance of the coat in heat tolerance of cattle. II. Effect of solar radiation on body temperatures

1960 ◽  
Vol 11 (5) ◽  
pp. 871 ◽  
Author(s):  
DF Dowling
Keyword(s):  
Body Temperature ◽  
Solar Radiation ◽  
The Body ◽  
Body Temperatures ◽  
Hair Coat ◽  
Transparent Plastic ◽  
Mean Body Temperature ◽  
Clear Plastic ◽  
The Mean ◽  
The Difference

An experiment was performed to test the effect of solar radiation on the body temperatures of cattle, both clipped and with hair coat, in a clear transparent plastic covering as compared with cattle in a white reflective plastic covering. The mean body temperature of the animals in white plastic coats was 0.15°F lower than that of animals in clear plastic coats. This difference was highly significant statistically (P< 0.001). Animals in both clear and white coats had higher body temperatures than controls without plastic coats. The difference was highly significant, and was about 1.5°F in the clipped animals.

Body cooling and response to heat

1961 ◽  
Vol 16 (2) ◽  
pp. 235-238 ◽  
Author(s):  
J. H. Veghte ◽  
Paul Webb
Keyword(s):  
Body Temperature ◽  
Water Immersion ◽  
Heat Exposure ◽  
The Body ◽  
Central Control ◽  
Mean Body Temperature ◽  
Gradient Effect ◽  
Sudomotor Activity ◽  
Body Cooling ◽  
High Level

Prior body cooling with cold air or water immersion increased human tolerance to a high level of heat stress. The lower the body temperature at the onset of the heat exposure, the greater the increase in tolerance times over the control values. Mean body temperature was the only discriminating criterion which successfully correlated with tolerance time in these experiments. Sudomotor activity in heat was inhibited by prior body cooling. It is postulated that the onset of sweating is due to a gradient effect, not to either peripheral or central control. Submitted on October 5, 1960

Some aspects of body temperature regulation in sheep

1968 ◽  
Vol 71 (1) ◽  
pp. 61-66 ◽  
Author(s):  
M. E. D. Webster ◽  
K. G. Johnson
Keyword(s):  
Body Temperature ◽  
Surface Area ◽  
Cold Water ◽  
The Body ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Merino Sheep ◽  
Infra Red ◽  
Heat Increment ◽  
Skin Temperatures

SummarySkin temperatures, deep body temperatures and respiratory rates have been measured in Southdown and Merino sheep following feeding, and during infra-red irradiation, rumen infusions of hot and cold water, and cold exposure induced by shearing. The increases in respiratory rate and skin temperatures induced by infra-red heating and the heat increment of feeding were reversed by addition of iced water to the rumen and were suppressed by shearing. These responses could not be systematically related to particular body temperatures in the sheep and appeared to be continuously variable rather than ‘all-or-none’ phenomena. Considerable overlap was observed between respiratory and vasomotor mechanisms of thermoregulation. Measurements of the surface area and weight of ears and legs showed that these regions contribute approximately 23% of the surface area and 8% of the body weight in Merino sheep. Calculations suggested that up to 70% of the additional heat produced in the 2 h after feeding in sheep may be stored in the tissues through increase in mean body temperature. Sheep kept in short wool throughout the winter appeared to establish a new thermoregulatory ‘set-point’ associated with lower rectal temperatures than those in sheep with a full fleece.

scholarly journals PERBEDAAN SUHU TUBUH BAYI BARU LAHIR ANTARA BAYI YANG BERHASIL MELAKUKAN INISIASI MENYUSU DINI DAN BAYI YANG TIDAK BERHASIL MELAKUKAN INISIASI MENYUSU DINI

2019 ◽  
Vol 2 (2) ◽  
pp. 133
Author(s):  
Aprilia Aprisanti Reyani
Keyword(s):  
Body Temperature ◽  
Random Sampling ◽  
Statistical Tests ◽  
The Body ◽  
Breastfeeding Initiation ◽  
Chi Square ◽  
Cross Sectional ◽  
Chi Square Test ◽  
The Difference ◽  
Cross Sectional Design

Latar Belakang :Kehangatan dada ibu dapat menghangatkan bayi, sehingga apabila bayi diletakan di dada ibunya segera setelah melahirkan atau dilakukan Inisiasi Menyusu Dini, dapat menurunkan resiko hipotermia dan menurunkan kematian bayi baru lahir akibat kedinginan atau hipotermia. Tujuan : Tujuan dari penelitian ini adalah untuk mengetahui perbedaan suhu tubuh bayi baru lahir antara bayi yang berhasil melakukan IMD dan bayi yang tidak berhasil melakukan IMD Metode  :Analitik,desain cross sectional,populasi semua bayi baru lahir, sampel bayi barulahir, teknik Non Random Sampling, pengumpulan data dengan menggunakan Lembar Observasi dengan menggunakan uji Chi-Square dengan nilai signifikan α = 0.05 yaitu bila hasil uji statistik menunjukan p ≤ α maka H0 ditolak. Hasil      :Suhu tubuh bayi baru lahir yang berhasil melakukan IMD sebagianbesardengansuhutubuhtidakhipotermisebanyak 20 bayi (87%) Suhu tubuh bayi baru lahir yang tidak berhasil melakukan IMD sebagianbesardengansuhutubuhhipotermisebanyak 8 bayi (66,7%). Dari hasil uji statistik diperoleh hasil nilai p = 0,005 < α = 0.05 maka H1 diterima, artinya ada Perbedaan suhu tubuh bayi baru lahir yang berhasil melakukan IMD dan yang tidak berhasil melakukan IMD Kesimpulan :Terdapat perbedaan suhu tubuh bayi baru lahir antara bayi yang berhasil melakukan IMD dan bayi yang tidak berhasil melakukan IMD.   Kata kunci : Inisiasi Menyusu Dini, Suhu Tubuh Bayi Baru Lahir                                                                                               THE DIFFERENCE BODY TEMPERATURE BETWEEN BABIES WHO SUCCESSFULLY INITIATE BREASTFEEDING EARLY AND BABIESWHO FAIL TO INITIATE EARLY BREASTFEEDING AT RSIA KIRANA SIDOARJO 2019  Background : The warmth of the mother’s chest can warm the baby, so that when the baby is in the mother’s breast immediately after birth or initiated early breastfeeding can reduce the mortality rate of newborns due to hypotermia.Purpose :the purpose of this study was to determine the difference in body temperature of newborns between infants who successfully initiated early breastfeeding and infants who did not succeed in initiating early breastfeedingMethods : analytical, cross sectional design, population 40 newborns, samples 35 newborns, Non Random Sampling techniques, the data accumulation using observation sheets and using chi-square test, with significant value α = 0.05 is when the statistical test results show p ≤ α then Ho is rejected.Result : The body temperature of the newborn who succeeded in initiating early breastfeeding was 36.78ºC with 23 (65.7%) of infants none having hypothermia, the newborn baby's body temperature that did not succeed in doing this early breastfeeding was 35.78ºC With 8 infants experiencing hypothermia, while 4 babies with normal temperature. From the results of statistical tests obtained results with the value p = 0,000 <α = 0.05 then H1 accepted, meaning there is a difference in body temperature of a newborn who successfully initiated early breastfeeding and who did not succeed in Early Breastfeeding Initiation. Conclusion : There is a difference in the body temperature of a newborn between infants who successfully initiated breastfeeding and infants who are not successful in initiating early breastfeeding....Keywords : Early breastfeedinginitiation, newborns temperature

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

scholarly journals FACTORS INFLUENCING THE CORRELATION BETWEEN DIFFERENCES OF ELECTRIC POTENTIAL IN THE SKIN OF HUMAN SUBJECTS AND BASAL METABOLISM

1931 ◽  
Vol 54 (6) ◽  
pp. 789-800 ◽  
Author(s):  
Charlotte Purdy ◽  
Charles Sheard
Keyword(s):  
Metabolic Rate ◽  
Electric Potential ◽  
Human Subjects ◽  
Inverse Correlation ◽  
The Body ◽  
Metabolic Rates ◽  
Electric Potentials ◽  
Per Se ◽  
The Difference ◽  
Circulation Of The Blood

High metabolic rates are associated normally with small differences of electric potential, whereas low metabolic rates are associated with large differences of electric potential as measured on the extremities of the body. Within the normal range of metabolism there appears to be a definite correlation between the metabolic rates and the difference of electric potential over a specified area of the skin, provided the person under test has no abnormalities of the circulatory system or of the functions of the skin. If there are no dysfunctions of the circulation or of the skin, the metabolic rate may be calculated, within ±4 points, from the expression See PDF for Equation where x is the metabolic rate and y is the difference of electric potential across the specified areas of skin (electrodes 12 cm. apart). In general, there are abnormalities of the circulation of the blood or of the functions of the skin of persons for whom the metabolic rates determined by the two methods (difference of electric potentials and gasometric procedures) do not agree with ±4 points. Manifest retardation or return to normality in the rate of circulation of the blood, such as may be produced by the sphygmomanometric cuff under varying pressures, produces marked changes in the difference of electric potentials obtained across a specified intervening area of skin. Retardation of flow of blood produces increased differences of electric potential. Preliminary investigations indicate that there is an inverse correlation between cutaneous temperatures and differences of electric potential. Day by day variations, emotive effects and the partaking of food have less effect, in general, on the electric potentials across a specified area of skin than they have on the metabolic rates. These experimental results indicate that there may be a more direct correlation between electric potentials and the circulation of the blood per se than between electric potentials and the metabolism of the body per se. When normality of circulation of the blood and of the functions of the skin exists in the areas under test for differences of electric potential, there is apparently a correlation between metabolic rates and electric potentials.

Body temperature and vasomotor responses in Scottish Blackface and Tasmanian Merino sheep subjected to slow cooling

1968 ◽  
Vol 10 (3) ◽  
pp. 265-282 ◽  
Author(s):  
J. Slee
Keyword(s):  
Blood Flow ◽  
Body Temperature ◽  
Environmental Temperature ◽  
The Body ◽  
Slow Cooling ◽  
Merino Sheep ◽  
Cool Environment ◽  
One Year ◽  
Skin Temperatures ◽  
Increased Blood Flow

1. Scottish Blackface and Tasmanian Merino one-year-old males were exposed to cold in climate chambers. The environmental temperature fell slowly from +10°C to −15°C in the first experiment when the sheep were in full fleece and from +30°C to −5°C in the second experiment when the same sheep were closely shorn. In the second experiment each sheep received two identical exposures separated by one day spent in a cool environment. Rectal temperatures and skin temperatures on the body and the extremities were recorded.2. In experiment 1 skin temperatures on the feet and ears generally fell sharply due to vasoconstriction, especially in the Blackface sheep. The Blackface sheep showed earlier and more intense vasoconstriction than the Merinos.3. In experiment 2 foot and ear skin temperatures fell smoothly with gradual vasoconstriction. In contrast to experiment 1, both breeds were similar in the time of onset of vasoconstriction. Foot temperatures, however, were significantly higher and vasoconstriction correspondingly later during the second exposure of experiment 2 than during the first exposure.4. The skin temperature at which vasoconstriction occurred remained similar irrespective of breed, shearing or exposure occasion. But the ambient temperature at vasoconstriction was significantly influenced by all these variables.5. Cold-induced vasodilatations were more frequent in experiment 1 than in experiment 2.6. Retarded vasoconstriction among the Merinos in experiment 1 could, except for two sheep, be accounted for by their superior fleece cover. In experiment 2, the delayed foot vasoconstriction on second exposure was attributed to increased blood flow resulting from acclimatization.

scholarly journals Field-based body temperatures reveal behavioral thermoregulation strategies of the Atlantic marsh fiddler crab Minuca pugnax

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244458
Author(s):  
Sarah Hews ◽  
Zahkeyah Allen ◽  
Adrienne Baxter ◽  
Jacquline Rich ◽  
Zahida Sheikh ◽  
...  
Keyword(s):  
Body Temperature ◽  
Surface Temperature ◽  
Fiddler Crab ◽  
Cooling Capacity ◽  
The Body ◽  
Behavioral Thermoregulation ◽  
Body Temperatures ◽  
Intertidal Crab ◽  
Trade Offs ◽  
The Difference

Behavioral thermoregulation is an important defense against the negative impacts of climate change for ectotherms. In this study we examined the use of burrows by a common intertidal crab, Minuca pugnax, to control body temperature. To understand how body temperatures respond to changes in the surface temperature and explore how efficiently crabs exploit the cooling potential of burrows to thermoregulate, we measured body, surface, and burrow temperatures during low tide on Sapelo Island, GA in March, May, August, and September of 2019. We found that an increase in 1°C in the surface temperature led to a 0.70-0.71°C increase in body temperature for females and an increase in 0.75-0.77°C in body temperature for males. Body temperatures of small females were 0.3°C warmer than large females for the same surface temperature. Female crabs used burrows more efficiently for thermoregulation compared to the males. Specifically, an increase of 1°C in the cooling capacity (the difference between the burrow temperature and the surface temperature) led to an increase of 0.42-0.50°C for females and 0.34-0.35°C for males in the thermoregulation capacity (the difference between body temperature and surface temperature). The body temperature that crabs began to use burrows to thermoregulate was estimated to be around 24°C, which is far below the critical body temperatures that could lead to death. Many crabs experience body temperatures of 24°C early in the reproductive season, several months before the hottest days of the year. Because the use of burrows involves fitness trade-offs, these results suggest that warming temperatures could begin to impact crabs far earlier in the year than expected.

scholarly journals ALOE VERA BARBADENSIS MILLER AS AN ALTERNATIVE TREATMENT FOR CHILDREN WITH FEVER

2017 ◽  
Vol 3 (5) ◽  
pp. 595-602
Author(s):  
Siti Choirul Dwi Astuti ◽  
Suhartono Suhartono ◽  
Ngadiyono Ngadiyono ◽  
Supriyana Supriyana
Keyword(s):  
Body Temperature ◽  
Alternative Therapy ◽  
Aloe Vera ◽  
The Body ◽  
Warm Water ◽  
Control Group ◽  
Control Group Design ◽  
Quasi Experimental ◽  
The Difference ◽  
And Control

Background: Applying a cooling treatment from outside the body is one way to lower fever in children. Midwives commonly perform a warm water compress in their care, but it is considered less effective. Thus, compress with aloe vera barbadensus miller is proposed in this study as an alternative treatment.Objective: To examine the effect of Aloe vera barbadensis miller compress in reducing body temperature in children with fever.Methods: This was a quasi-experimental study with pretest and posttest with control group design. Forty children were recruited, with twenty of them assigned in each group. Purposive sampling was performed to select the sample. A digital rectal thermometer was used to measure the temperature. Independent t- test and paired test were used for data analysis.Results: Findings showed that the aloe vera compress group showed a higher decrease of body temperature compared to the warm water compress group. The difference of body temperature after 20 minutes in the experiment group was 1.435 while in the control group was only 1.085. There were statistically significant differences in body temperature between the experiment and control group (p=0.013).Conclusion: Aloe vera barbadensis miller compress is an effective alternative therapy in reducing body temperature in children with fever.  It is recommended for midwives to apply this intervention to reduce body temperature significantly.

scholarly journals A supplementation study in human subjects with a combination ofmeso-zeaxanthin, (3R,3′R)-zeaxanthin and (3R,3′R,6′R)-lutein

2008 ◽  
Vol 100 (6) ◽  
pp. 1307-1314 ◽  
Author(s):  
David I. Thurnham ◽  
Aurélie Trémel ◽  
Alan N. Howard
Keyword(s):  
Liquid Chromatography ◽  
Human Subjects ◽  
Plasma Concentrations ◽  
The Body ◽  
Lower Plasma ◽  
Chiral Column ◽  
Plasma Response ◽  
Pure Substances ◽  
The Difference ◽  
Β Carotene

We measured the blood uptake ofmeso-zeaxanthin (MZ) from a mixture of macular pigments since its bioavailability in man has not been studied. Volunteers (ten men and nine women) were recruited and received one capsule of Lutein Plus®/d. Blood was taken at baseline, day 10 and day 22. One capsule contained 10·8 mg lutein, 1·2 mg (3R,3′R)-zeaxanthin and 8·0 mg MZ. Plasma lutein and total zeaxanthin concentrations were quantified using isocratic liquid chromatography and the eluting xanthophyll fractions were collected and re-chromatographed on a chiral column to assess the proportion of MZ. Plasma concentrations per mg dose at day 22 suggested that (3R,3′R)-zeaxanthin (0·088 μmol/l per mg) was about 50 % more actively retained by the body than lutein (0·056 μmol/l per mg) (although the difference was not significant in women) and 2·5–3·0 times more than MZ (0·026 μmol/l per mg). Concentrations of MZ at day 22 were 2·5 times higher in women than men. The plasma responses from lutein and (3R,3′R)-zeaxanthin in the Lutein Plus®were lower than literature values for the pure substances. That is, their uptake into plasma appeared to be slightly depressed by the presence of MZ. Plasma concentrations of β-carotene were depressed by about 50 % at day 10 and about 35 % at day 22. In conclusion, the lower plasma response to MZ compared with (3R,3′R)-zeaxanthin probably indicates that MZ is less well absorbed than (3R,3′R)-zeaxanthin but work with pure MZ will be needed to confirm that the lower plasma response was not due to the large amount of lutein in the Lutein Plus®.

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