Spiracular Structure and Water Loss from Tribolium confusum Jacq. and Sitophilus granarius (L.) under Reduced Pressures

1963 ◽  
Vol 95 (4) ◽  
pp. 352-357 ◽  
Author(s):  
J. Sharplin ◽  
H. J. Bhambhani
Keyword(s):  
Water Loss ◽  
Tribolium Confusum ◽  
The Body ◽  
Sitophilus Granarius ◽  
Reduced Pressure ◽  
Low Pressures ◽  
Anomalous Water ◽  
Reduced Pressures

AbstractThe structure and position of the spiracles in Sitophilus granarius and Tribolium confusum adults was studied. On the basis of this an attempt was made to explain the differences in water loss from these two species under reduced pressure. It was concluded that the spiracular structure combined with the inflation of the body under very low pressures, can account for the apparently anomalous water loss results.

Responses of Pests to Fumigation. VI.—Water Losses and the Mortality of Calandra Spp. at reduced Pressures

1956 ◽  
Vol 47 (4) ◽  
pp. 749-753 ◽  
Author(s):  
H. J. Bhambhani
Keyword(s):  
Water Loss ◽  
Pressure Range ◽  
High Humidity ◽  
Physical Change ◽  
Water Losses ◽  
Mortality Response ◽  
Relative Humidity Range ◽  
Low Pressures ◽  
Humidity Range ◽  
Reduced Pressures

The water loss and mortality of Calandra granaria (L.) and C. oryzae (L.) have been studied at low pressures in controlled humidities. The mortality of both species is closely associated with the loss of water under these conditions, a loss which is prevented by a high humidity in the surrounding air. C. oryzae is consistently more susceptible than C. granaria. Substantially linear relations were observed between water loss and decreasing relative humidity (range 0–85%), increasing period of exposure (range 4–16 hr.), and decreasing pressure (range 2–8 cm. mercury). At lower pressures (3–4 mm. mercury), the Water loss and mortality of both species were greatly reduced, suggesting that some physical change had occurred in the insects. A covariance analysis of the mortality response, using the loss of water as a concomitant variate, showed that there was no significant part of the mortality that was not accounted for by the water loss from the insects.

scholarly journals The influence of pressure on the boiling points of metals

1910 ◽  
Vol 83 (565) ◽  
pp. 483-491 ◽  
Keyword(s):  
Atmospheric Pressure ◽  
Boiling Point ◽  
High Vacuum ◽  
Similar Type ◽  
Exact Relation ◽  
Reduced Pressure ◽  
Boiling Points ◽  
Experimental Values ◽  
Low Pressures ◽  
Very High

Part I. — Pressures below 760 mm . In a previous communication (‘Proc.’, A, vol. 82, 1909, p. 396) the approximate boiling points of a number of metals were determined at atmospheric pressure. Apart from the question of finding the exact relation between the boiling point and pressure, it is an important criterion of any method for fixing the temperatures of ebullition to demonstrate that the experimental values obtained are dependent on the pressure. It is specially desirable when dealing with substances boiling at temperatures above 2000° to have some evidence that the points indicated are true boiling points. Previous work on the vaporisation of metals at different pressures has been confined to experiments in a very high vacuum except for metals like bismuth, cadmium, and zinc, which boil at relatively low temperatures under atmospheric pressure. The observations were limited to very low pressures on account of the difficulty of obtaining any material capable of withstanding a vacuum at temperatures over 1400° and the consequent necessity for keeping the boiling point below this limit by using very low pressures. Moreover in the case of the majority of the metals, e. g. , copper, tin, ebullition under reduced pressure has never been observed. The difficulties indicated above were avoided by using a similar type of apparatus to that previously described, and arranging the whole furnace inside a vacuum enclosure, thus permitting of the use of graphite crucibles to contain the metal.

Evolution of water balance in the genusDrosophila

2001 ◽  
Vol 204 (13) ◽  
pp. 2331-2338 ◽  
Author(s):  
Allen G. Gibbs ◽  
Luciano M. Matzkin
Keyword(s):  
Water Balance ◽  
Water Loss ◽  
The Body ◽  
The Other ◽  
Arid Environments ◽  
Physiological Mechanisms ◽  
Dehydration Tolerance ◽  
Cactophilic Drosophila ◽  
Adaptive Mechanisms ◽  
The World

SUMMARYFruit flies of the genus Drosophila have independently invaded deserts around the world on numerous occasions. To understand the physiological mechanisms allowing these small organisms to survive and thrive in arid environments, we performed a phylogenetic analysis of water balance in Drosophila species from different habitats. Desert (cactophilic) species were more resistant to desiccation than mesic ones. This resistance could be accomplished in three ways: by increasing the amount of water in the body, by reducing rates of water loss or by tolerating the loss of a greater percentage of body water (dehydration tolerance). Cactophilic Drosophila lost water less rapidly and appeared to be more tolerant of low water content, although males actually contained less water than their mesic congeners. However, when the phylogenetic relationships between the species were taken into account, greater dehydration tolerance was not correlated with increased desiccation resistance. Therefore, only one of the three expected adaptive mechanisms, lower rates of water loss, has actually evolved in desert Drosophila, and the other apparently adaptive difference between arid and mesic species (increased dehydration tolerance) instead reflects phylogenetic history.

Eco-Physiological Studies of an Intertidal Crustacean, Pollicipes Polymerus (Cirripedia, Lepadomorpha)

1972 ◽  
Vol 57 (1) ◽  
pp. 83-102
Author(s):  
H. J. FYHN ◽  
J. A. PETERSEN ◽  
K. JOHANSEN
Keyword(s):  
Water Loss ◽  
Volume Regulation ◽  
Free Amino ◽  
Heat Load ◽  
Laboratory Experiments ◽  
Sea Water ◽  
Physiological Responses ◽  
The Body ◽  
Air Exposure ◽  
Pollicipes Polymerus

1. Physiological responses to environmental stresses of the intertidal cirriped Pollicipes polymerus have been studied by combined field and laboratory experiments. 2. The body temperature of air-exposed animals is always lower than expected from the heat load. Evaporation from the peduncle is responsible for the heat loss. 3. The rate of water loss by evaporation from the peduncle cuticle is 1.5 µl/cm2 h mmHg both at 21 and 27 °C. The transpiration is proportional to the saturation deficit of the air. The water loss from the capitulum is negligible in comparison to that from the peduncle. 4. The haemolymph osmolality of animals in the field increases during exposure to sunshine and decreases during exposure to rain. The increase in haemolymph osmolality during desiccation is equal to that calculated from the decrease in body water. The water loss during air exposure is adequately replaced during submersion, probably by osmosis. 5. Pollicipes is an osmoconformer but is 5-20 m-osmoles hyperosmotic. It tolerates sea-water dilutions down to about 50%. The hyperosmolality seems to be balanced by a high internal hydrostatic pressure. 6. An excretory activity is observed. The excretion is isosmotic to the haemolymph and is possibly an ultrafiltrate of the latter. 7. The muscle cells show volume regulation, but free amino acids seem to be unimportant in regulation of intracellular osmolality. The concentration of ninhydrinpositive substances in the muscle tissue is about 200 mM for animals in full strength sea water.

Deterrent activity of hops flavonoids and their derivatives against stored product pests

2017 ◽  
Vol 107 (5) ◽  
pp. 592-597 ◽  
Author(s):  
J. Jackowski ◽  
J. Popłoński ◽  
K. Twardowska ◽  
J. Magiera-Dulewicz ◽  
M. Hurej ◽  
...  
Keyword(s):  
Model Compound ◽  
Tribolium Confusum ◽  
Sitophilus Granarius ◽  
Antifeedant Activity ◽  
Trogoderma Granarium ◽  
Stored Product Pests ◽  
Deterrent Activity

AbstractFive flavonoids from hops, two of their derivatives, along with naringenin used as a model compound, were tested for their antifeedant activity against three coleopteran stored product pests: Sitophilus granarius L., Tribolium confusum Duv. and Trogoderma granarium Everts. The introduction, into the tested flavonoid molecules, of additional structural fragments such as prenyl or dimethylpyran moiety, is proposed to significantly alter the deterrent activity of the compounds. The prenyl moiety in flavonoids increased the deterrent activity of these compounds in all three of the grain feeding species used in the tests. It is also concluded that the introduction of dimethylpyran moiety to the flavonoid structure increases its deterrent activity in S. granarius and T. confusum, but in one of the test insects, T. granarium, an increased feeding was observed in response to the introduction of dimethylpyran moiety to the flavonoid structure.

scholarly journals Impact of Casting and Splinting Manipulations on Below-Dressing Pressures: An Experimental Model

Hand ◽  
2018 ◽  
Vol 14 (1) ◽  
pp. 48-55
Author(s):  
Nikhil Adapa ◽  
Kanu S. Goyal
Keyword(s):  
Soft Tissue ◽  
Pressure Transducer ◽  
Pressure Measurements ◽  
Reduced Pressure ◽  
Soft Tissue Swelling ◽  
Human Forearm ◽  
The Mean ◽  
Mean Compliance ◽  
Elastic Bandage ◽  
Reduced Pressures

Background: We tested how different applications of casts and splints affect underlying below-dressing pressures and how these dressings respond to swelling. Methods: A 3-in polyvinyl chloride pipe with an attached 100 mL saline bag to the outer surface was used to simulate a human forearm. A pressure transducer was attached to the bag and connected to a monitor providing continuous pressure measurements. Either a circumferential fiberglass cast or single-sided plaster splint was applied around the bag. To simulate the dressing’s compliance to soft tissue swelling, change in pressure was measured after 25 mL of saline was injected into the bag. Compliance was determined by calculating change in volume over change in pressure as volume was added. Results: In our 150 mL model, cast bivalving reduced pressure up to 28%, and splitting the cotton padding of a splint reduced pressures up to 33%. The mean compliance (ability to accommodate swelling) across all volume intervals was 182% greater in a bivalved cast versus a cast and 21% greater in a cotton-split splint versus a splint. Below-dressing pressure of a tightly wrapped elastic bandage was up to 2.76× greater than a medium tension bandage and up to 6.44× greater than a loosely applied bandage. A splint with real cotton padding had a 28% greater pressure than a splint with synthetic soft-roll padding. Conclusions: Splitting a dressing, utilizing synthetic cotton padding, and applying an elastic bandage cautiously can help reduce surface pressures and allow the construct to be more accommodating to soft tissue swelling.

scholarly journals Estimation of Time-Course Core Temperature and Water Loss in Realistic Adult and Child Models with Urban Micrometeorology Prediction

2019 ◽  
Vol 16 (24) ◽  
pp. 5097 ◽  
Author(s):  
Toshiki Kamiya ◽  
Ryo Onishi ◽  
Sachiko Kodera ◽  
Akimasa Hirata
Keyword(s):  
Core Temperature ◽  
Water Loss ◽  
Urban Areas ◽  
Time Course ◽  
The Body ◽  
Computational Method ◽  
Heat Index ◽  
Computational Techniques ◽  
Ambient Conditions ◽  
Urban Micrometeorology

Ambient conditions may change rapidly and notably over time in urban areas. Conventional indices, such as the heat index and wet bulb globe temperature, are useful only in stationary ambient conditions. To estimate the risks of heat-related illness, human thermophysiological responses should be followed for ambient conditions in the time domain. We develop a computational method for estimating the time course of core temperature and water loss by combining micrometeorology and human thermal response. We firstly utilize an urban micrometeorology prediction to reproduce the environment surrounding walkers. The temperature elevations and sweating in a standard adult and child are then estimated for meteorological conditions. With the integrated computational method, we estimate the body temperature and thermophysiological responses for an adult and child walking along a street with two routes (sunny and shaded) in Tokyo on 7 August 2015. The difference in the core temperature elevation in the adult between the two routes was 0.11 °C, suggesting the necessity for a micrometeorology simulation. The differences in the computed body core temperatures and water loss of the adult and child were notable, and were mainly characterized by the surface area-to-mass ratio. The computational techniques will be useful for the selection of actions to manage the risk of heat-related illness and for thermal comfort.

WATER-LOSS FROM THE BODY

The Lancet ◽  
1957 ◽  
Vol 269 (6976) ◽  
pp. 998-999
Author(s):  
AyubK. Ommaya
Keyword(s):  
Water Loss ◽  
The Body

Water Balance of the Camel

1956 ◽  
Vol 185 (1) ◽  
pp. 185-194 ◽  
Author(s):  
Bodil Schmidt-Nielsen ◽  
Knut Schmidt-Nielsen ◽  
T. R. Houpt ◽  
S. A. Jarnum
Keyword(s):  
Body Weight ◽  
Water Loss ◽  
Plasma Concentrations ◽  
The Body ◽  
Evaporative Water Loss ◽  
Weight Changes ◽  
Evaporative Water ◽  
Hot Environment ◽  
Dry Food ◽  
High Degree

Camels ( Camelus dromedarius) were exposed to prolonged periods of water deprivation during winter, spring and summer in the Sahara desert. Determinations were made of: weight changes, water and food intake, urine flow and concentrations, plasma concentrations, etc. It was found that the camel can tolerate a loss of water corresponding to 30% of its body weight even when exposed to the severe desert heat. Other mammals dehydrated in a hot environment may die from circulatory failure already when the water loss involves 12% of the body weight. Unlike many other mammals the camel does not lose its appetite when deprived of water but continues to eat normally until the desiccation becomes very severe. It has a low urine output (0.5–1 l/day when kept on a diet of dates and hay), a low water content in the feces, and, when dehydrated in the summer, a very low evaporative water loss. When offered water the camel drinks in 10 minutes enough water for complete rehydration. The longest period that we kept a camel on dry food without drinking water in the hot summer was 17 days. This camel was not working and it had its protective fur which decreased the heat gain from the environment. It is concluded that the ability of the camel to withstand prolonged dehydration is due to: a) tolerance to an extremely high degree of desiccation of the body and b) low overall water expenditure. Particularly effective as a water conserving mechanism is the low evaporative water loss during dehydration in the summer.

Responses of Pests to Fumigation. IV.—The responses of Calandra spp. to Reduced Pressures

1953 ◽  
Vol 44 (4) ◽  
pp. 651-656 ◽  
Author(s):  
A. K. M. El Nahal
Keyword(s):  
Water Vapour ◽  
Direct Effect ◽  
Water Loss ◽  
Direct Action ◽  
Practical Importance ◽  
Reduced Pressures

The direct action of reduced pressures, in the absence of any fumigant, on C. oryzae and C. granaria have been investigated in glass chambers of about 1 litre capacity. C. oryzae is sufficiently sensitive to make the direct effect of reducing the pressure within the range 2 to 10 cm. mercury of some practical importance, but C. granaria is more resistant. Mortality of both species increases for exposure periods of up to 8 hr. and for increased temperatures from 20°C. to 28°C. A large part of the observed mortality must be associated with enhanced water-loss from the insects at reduced pressures, as little response occurs when the atmosphere is kept saturated with water-vapour.

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