(n.) The state of torpidity induced by the heat and dryness of summer, as in certain snails; -- opposed to hibernation.
(n.) The arrangement of the petals in a flower bud, as to folding, overlapping, etc.; prefloration.
Example Sentences:
(1) Contrastingly, the hepatopancreas of aestivated snails when treated with ganglionic extracts of active snails showed increased specific activities of both enzymes.
(2) A wide size range of both species of snail were found to aestivate, but there was differential mortality of young B. rohlfsi soon after the lake re-filled, and the optimally surviving size group of B. globosus was 9 mm.
(3) Upon entering into aestivation, Protopterus aethiopicus develops a respiratory acidosis.
(4) On re-activation of some aestivating snails, betion of ATP and Mg2+ to the isolated gut contents or to extracts from washed gut walls led to the formation of higher-molecular-weight forms of the enzyme, beta-glucosidase A (mol.wt.
(5) Snails in the aestivated group were completely inactive for 8 weeks beginning at age 23 weeks.
(6) The cessation of water intake from the start of aestivation results in hemoconcentration and marked oliguria.
(7) This was not correlated to metabolic rate suggesting that glycolytic rate was reduced in this tissue in the early stages of aestivation, possibly due to a change in fuel use.
(8) The molluscicide would then be released at the unpredictable start of the next wet season and kill any snails which survive the drought by aestivation.
(9) Infective larvae aestivate in the faeces or in the soil of the lucerne pastures in the dry, hot summer months and migrate on to the herbage during the cool, wet autumn.
(10) X-ray microanalyses of ultrathin frozen sections from aestivating and non-aestivating snails have shown gradients of chloride and potassium ions in the apical microvillus region of the regulating mantle collar epithelium.
(11) A cocoon formed from a single cell layer of shed stratum corneum may reduce water loss from the skin of desert-dwelling frogs while these aestivate in soil-filled burrows.
(12) The possible roles of these ions, pH and substrate in the modulation of fructose diphosphatase and gluconeogenic activity in the lungfish are discussed in relation to aestivation and temperature adaptation.
(13) The activity levels of both enzymes decreased in aestivating snails.
(14) Aestivation patterns in Bulinus rohlfsi and B. globosus were studied by digging transects across the floor of their dried habitats and by monitoring changes in snail population structure during the period when the habitats were flooded.
(15) As aestivation continued, the number of breaths per tachypneic period increased gradually to reach a steady level at about the 3rd mo.
(16) The beginning of aestivation in B. rohlfsi did not correlate with any of the physical parameters measured, but it coincided with the dying off of a bloom of unicellular algae.
(17) The importance of stimuli other than desiccation in the aestivation process of bulinids is stressed.
(18) X-ray microanalysis of unfixed thin sections shows that there is a concentration gradient of ions within these cells in aestivating animals which is not present in stimulated snails.
(19) Bulinus rohlfsi, which inhabited a small man-made lake, was found to aestivate towards the bottom of its habitat, aestivation occurring during the last six weeks before the lake dried.
(20) A. nuchalis thus appears to be an opportunistic vernal breeder, limited only by the availability of resources, whereas A. caudicinctus, which apparently displays the greater reproductive effort of the two species, has a typical aestival pattern of breeding which is uniquely attuned to the enormous burst of productivity occurring in this arid region following the substantial and predictable summer cyclonic rains.
Hibernation
Definition:
(n.) The act or state of hibernating.
Example Sentences:
(1) Based on the fact that all hibernators, at their regulated minimal body temperature, display a uniform turnover rate, related to body weight, the hypothesis is developed that cold tolerance of mammals is generally limited by a common specific minimal metabolic rate, which larger organisms, because of their lower basal metabolism, already attain in less profound hypothermia.
(2) Throughout the hibernation season (October to April), white adipose tissue-saturated FA percentage decreased, monoene percentage remained constant, and diene percentage increased.
(3) The role of cyclic changes of protein synthesis rate in adaptation of cells of hibernating mammals to functioning at various temperatures is discussed.
(4) In this animal, central vasopressin infusion during the winter prevents hibernation.
(5) To clarify the cause of uncoupling of Ca influx through Ca channels and the contractility of the myocardium in hibernating chipmunks, the electromechanical effects of two different internal Ca store inhibitors, caffeine and ryanodine, and a cardiotonic agent, isoprenaline, were investigated in papillary muscles of hibernating animals.
(6) The mechanism(s) regulating the duration of the period of hibernation was considered to be concerned with some aspect of metabolism and probably the same for all three species.
(7) The possible mechanisms in regulation of the respiration rate of mitochondria from liver of hibernating ground squirrels have been investigated.
(8) Does ursodeoxycholic acid (UDC) production protect hibernating species of Ursidae against gallstone disease?
(9) Such responses to equithesin were not observed in the non-hibernating rodent species.
(10) In neurons from other structures (lateral septum, medial preoptic area, hippocampus) in the brain slices of both hibernating and waking ground squirrels, thyrotropin-releasing hormone did not usually affect the level of spontaneous discharges.
(11) Fetal mesencephalic tissue was grafted into the lateral ventricle following pregraft refrigeration in calcium-free magnesium-free buffer at 4 degrees C. Fetal mesencephalic tissue was hibernated for 5, 12, 16, 20, 24, 28, 32 hours (group A, B, C, D, E, F and G, respectively).
(12) We find that during hibernation the marrow cavity of the long bones is filled with lipid deposits interspersed with vascular sinusoids containing mononuclear cells and red blood cells.
(13) Ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bears produced similar inhibition, with partial reversal by naloxone.
(14) We studied nutrient absorption across the brush-border membrane in jejunal tissues from active 13-lined ground squirrels and in hibernating squirrels that had not eaten for at least 6 wk.
(15) Plasma ANF of both groups of nonhibernating marmots was significantly higher (P less than 0.01) than that the hibernating group, but there was no difference between nonhibernating males and females.
(16) The CG and associated DB were therefore found to exert antagonistic effects which are responsible for the control of spermatogonial DNA synthesis in hibernating Helix aspersa.
(17) U69593, however, antagonized hibernation induced by HIT in summer active ground squirrels.
(18) Grafted fetal mesencephalic tissue which had been hibernated for 16 hours or less survived well.
(19) Over 60% of the blood CO2 stores accumulated at the beginning of the hibernation bout were released by hyperventilation during the first period, prior to the full development of thermogenesis.
(20) The heart of ground squirrels is covered by a large amount of brown adipose tissue during the whole period of hibernation.