Photoperiod influences endogenous rhythm of ambient temperature selection by the honeybee Apis mellifera

2012 ◽  
Vol 37 (8) ◽  
pp. 587-594 ◽  
Author(s):  
Przemysław Grodzicki ◽  
Michał Caputa
Keyword(s):  
Apis Mellifera ◽  
Ambient Temperature ◽  
Endogenous Rhythm ◽  
Temperature Selection

The effects of feeding and ecdysis on temperature selection by young garter snakes in a simple thermal mosaic

1989 ◽  
Vol 67 (1) ◽  
pp. 19-23 ◽  
Author(s):  
A. Ralph Gibson ◽  
Darlene A. Smucny ◽  
John Kollar
Keyword(s):  
Ambient Temperature ◽  
Diurnal Variation ◽  
Thamnophis Sirtalis ◽  
Garter Snakes ◽  
Thermoregulatory Behavior ◽  
Temperature Selection ◽  
Late Afternoon ◽  
Feeding Regime ◽  
High Level ◽  
Made In

Temperature selection by five young common garter snakes, Thamnophis sirtalis, was studied using a simple, two-choice thermal mosaic. The animals were housed in an arena (60 × 120 cm) within an environmental room, where they were exposed to a photoperiod of 12 h light: 12 h dark and a general ambient temperature of 20 °C. The arena contained two shelters (20 cm × 20 cm), one at ambient temperature and one heated to 30 °C. On a given day, we determined the snakes' locations in the arena twice an hour for several hours. Observations were made in this manner on most days over a period of 19 weeks. Within 1 h following a late afternoon feeding, use of the hot shelter increased from about 5–20% of observations to above 80%. Occupation of the heated shelter remained at a high level the next day and then decreased, reaching a background of 10–40% by the 3rd day after feeding. The animals displayed a higher background use when maintained on a weekly feeding regime than they did when on a biweekly regime. During a 5-day period preceding ecdysis, occupation of the hot shelter again exceeded 80% of observations; decline to a background of 0–10% began about the day of molt. Runs tests performed on the daily records of individuals indicate that hot-shelter use tended to occur in bouts. There was no suggestion of diurnal variation in thermoregulatory behavior.

The Ratio of Sunflower Pollens Foraged by Apis mellifera Is More Than That of Apis cerana Does During Sunflower Blooming

Sociobiology ◽  
2020 ◽  
Vol 67 (2) ◽  
pp. 256
Author(s):  
Huipeng Yang ◽  
Jia Sun ◽  
Peng Tang ◽  
Changsheng Ma ◽  
Shudong Luo ◽  
...  
Keyword(s):  
High Temperature ◽  
Apis Mellifera ◽  
Low Temperature ◽  
Ambient Temperature ◽  
Honey Bee ◽  
Apis Cerana ◽  
Pollen Foraging

Bias foraging of pollen is general in different pollinators since various nutrition demanding, co-evolution and interaction of insect-plant. To clarify the preference of pollen foraging during sunflower blooming, the pollen foraging behaviors of Apis mellifera Linnaeus and Apis cerana Fabricius were observed. Our results displayed that two summits of pollen foraging occurred in the morning before the ambient temperature climbed up to thirty-one degree centigrade and in the afternoon after the ambient temperature decreased below thirty-one degree centigrade, respectively. Notably, the first foraging summit of Apis cerana emerged one hour earlier than that of Apis mellifera. These results imply that Apis mellifera is less resistant to low temperature but more resistant to high temperature than Apis cerana does. The colonies were surrounded by sunflowers with sporadic weeds, while only few maize dispersed over two hundred meters away. However, no more than forty percent of total pollens foraged by Apis mellifera was from sunflower, and which was no more than twenty percent in Apis cerana group. These results suggest that sunflower pollens are not the prior choice for both honey bee species, while the ratio of sunflower pollens foraged by Apis mellifera is more than that of Apis cerana does.

scholarly journals Cold Ambient Temperature Promotes Nosema spp. Intensity in Honey Bees (Apis mellifera)

Insects ◽  
2017 ◽  
Vol 8 (1) ◽  
pp. 20 ◽  
Author(s):  
Gina Retschnig ◽  
Geoffrey Williams ◽  
Annette Schneeberger ◽  
Peter Neumann
Keyword(s):  
Apis Mellifera ◽  
Ambient Temperature ◽  
Honey Bees

SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

Crystallographic Characterization of Dislocation Loops in Irradiated Tungsten

1968 ◽  
Vol 26 ◽  
pp. 290-291
Author(s):  
Robert C. Rau
Keyword(s):  
Electron Microscope ◽  
Ambient Temperature ◽  
Dislocation Loops ◽  
Polycrystalline Specimen ◽  
Post Irradiation ◽  
Neutron Fluences

Previous work has shown that post-irradiation annealing, at temperatures near 1100°C, produces resolvable dislocation loops in tungsten irradiated to fast (E > 1 MeV) neutron fluences of about 4 x 1019 n/cm2 or greater. To crystallographically characterize these loops, tilting experiments were carried out in the electron microscope on a polycrystalline specimen which had been irradiated to 1.5 × 1021 n/cm2 at reactor ambient temperature (∼ 70°C), and subseouently annealed for 315 hours at 1100°C. This treatment produced large loops averaging 1000 Å in diameter, as shown in the micrographs of Fig. 1. The orientation of this grain was near (001), and tilting was carried out about axes near [100], [10] and [110].

Voids in Quenched Nickel

1968 ◽  
Vol 26 ◽  
pp. 266-267
Author(s):  
J. J. Laidler
Keyword(s):  
Electron Beam ◽  
Ambient Temperature ◽  
Cooling Rate ◽  
Three Dimensional ◽  
Cooling Curve ◽  
Polycrystalline Nickel ◽  
Quenching Temperature ◽  
Long Tail ◽  
Diffusion Pump

The presence of three-dimensional voids in quenched metals has long been suspected, and voids have indeed been observed directly in a number of metals. These include aluminum, platinum, and copper, silver and gold. Attempts at the production of observable quenched-in defects in nickel have been generally unsuccessful, so the present work was initiated in order to establish the conditions under which such defects may be formed.Electron beam zone-melted polycrystalline nickel foils, 99.997% pure, were quenched from 1420°C in an evacuated chamber into a bath containing a silicone diffusion pump fluid . The pressure in the chamber at the quenching temperature was less than 10-5 Torr . With an oil quench such as this, the cooling rate is approximately 5,000°C/second above 400°C; below 400°C, the cooling curve has a long tail. Therefore, the quenched specimens are aged in place for several seconds at a temperature which continuously approaches the ambient temperature of the system.

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