Showing papers in "Journal of Thermal Biology in 1991"

TL;DR: The high rates of heat transfer are such that individual naked mole-rats cannot regulate Tb over the entire range of measured Tas and, as such, are poikilothermic mammals.

TL;DR: Temperatures inside natural winter burrows of alpine marmots (Tbur) dropped exponentially throughout the hibernation season from about 12°C in autumn to almost 0°c in spring as discussed by the authors.

TL;DR: Two “endothermic temperature range” statistics are proposed which quantify the range of ambient temperatures over which an endotherm can remain potentially active.

TL;DR: It is suggested that a continuum may exist between the water-economy hypotheses and the endothermic temperature range hypothesis, dependent upon the refugia used, diet, water availability, and heat tolerance.

TL;DR: The basis of selective brain cooling in rats may be collecting cool blood from the head skin by the system of dural venous sinuses, which is responsible for cooling the brain in normothermic animals and hyperthermic animals.

TL;DR: The thermal tolerance of pyrogen-treated toads increased significantly over that of saline-injected toads if both groups of toads were incubated at a febrile temperature but not if they were incubation at a normothermic temperature.

TL;DR: This paper used data from heated taxidermic mounts of 6 avian species and 4 mammal species to determine the exponent c for the functional relation between heat transfer and wind speed, u.

TL;DR: The critical thermal maxima and minima, and upper and lower lethal limits of worker and soldier Coptotermes formosanus Shiraka and Reticulitermes flavipes Kollar were determined and no differences in LLL were observed.

TL;DR: The intraspecific exponents of body mass in relation to metabolic rate at different temperatures in this species are similar to those published for interspecific comparisons in other reptiles.

TL;DR: In winter-acclimatized pouched mice, body mass, resting metabolic rates and non-shivering thermogenesis capacity are higher than in summer-ac ClIMatized mice, while lower critical point and minimal thermal conductance are higher in summer’s mice than in winter's, which may help explain the ability of this species to cope with its habitat in the two different seasons.

TL;DR: The decrease in solar heat gain in winter coats is due largely to increased insulation and not to altered optical qualities, because the thermal effect of radiation penetrating more deeply into winter coats importantly counteracts the effects of these coat's higher reflectivity.

TL;DR: Changes in haematocrit, plasma osmolarity and chloride concentrations were monitored in the Antarctic teleost, Pagothenia borchgrevinki before and after exposure to a 10°C rise in water temperature.

TL;DR: In this article, the metabolic rate of three sub-adult polar bears (Ursus maritimus) was measured before and after exposure to a pool covered with a 1 cm slick of Midale crude oil.

TL;DR: In this paper, the authors measured before and after acclimation to heat (1 month at 34°C) with and without additional hypohydration stress and found that the improved endurance of acclimated young and 15 months old rats was associated with greater PV reserves and improved vasomotor response.

TL;DR: Comparative studies of the mating behaviour of coexisting but seasonally separated species may reveal microclimatic effects on insect mating systems, and large males were at an advantage during low ambient temperature, although for different reasons in the two species.

TL;DR: These results corroborate results obtained from northern hemisphere lizards, which implicate melatonin as an important seasonal cue for thermoregulatory response.

TL;DR: Beluga whale distribution in estuaries is partially determined by water temperature, and water temperature may be important for skin moult in adult beluga.

TL;DR: The yolk utilization efficiency increased with increasing temperature at hatching and decreased from hatching to yolk absorption, and no significant differences were found in total body length and water content.

TL;DR: The larger of the two nocturnal desert rodents, G. pyramidium, had a higher T es under all conditions, which is related to its lower surface area:volume ratio.

TL;DR: Both weight specific and age specific cooling rates were greater for raccoon dogs than for blue foxes, and those for live blue fox and raccoon dog pups weighing less than 65 and 90 g cooled down faster than dead pups of the same size.

TL;DR: Low metabolic rates, a high lower-critical point and high overall minimal thermal conductance seem to be important adaptations which help the steenbok to conserve water even when exposed to high ambient temperatures and, therefore, to inhabit extreme arid habitats.

TL;DR: In this paper, the authors used a thermal model to estimate the ice content of frozen wood frogs (Rana sylvatica) using the composition and thermal constants of their tissues to ascertain the impact of each parameter on estimates of ice content.

TL;DR: The maximal rise in T c diminished if the procedure was repeated daily for 43 days and increased abruptly again when the T c measurements were taken, in one session, in the presence of a rat.

TL;DR: In this article, the slope of the line relating metabolic rate to environmental temperatures below thermoneutrality is determined by their total thermal insulation (or conductance), and a straight line relationship can also be obtained when an animal's insulation changes with environmental temperature.

TL;DR: In rats and other animals which have safe refuges, hyperthermia interferes with the ability to continue exercising and there were no correlations between lactate concentraion andhyperthermia or endurance time.

TL;DR: It is suggested that microbial organisms within the caecum were active and functioning more effectively at 33°C (the preferred body temperature of the naked mole-rat) than at the other two temperatures.

TL;DR: The annual rhythm of the physiological state of eurythermic fish is an important factor for temperature acclimation and was more pronounced in winter and spring than in autumn.

TL;DR: Oxygen consumption and body temperture of Hawaiian brown noddies during late incubation and in the first 24 h after hatching were measured at ambient temperatures and the functional basis of the abrupt increase in thermoregulatory capacity with hatching is discussed.

TL;DR: The results suggest that changes in body temperature after acclimation to direct internal heat load depend on the heating schedule, and it is also assumed that a time memory ofinternal heat load is formed in rats after acclamation to intermittent heat stress.

TL;DR: The half-times of both activation and inactivation were membrane potential-dependent and were shorter at high temperatures than at lower ones, and at temperatures greater an 35°C, L channel currents decreased with increasing temperature.