Eco-Physiological Studies of An Intertidal Crustacean, Pollicipes Polymerus (Cirripedia, Lepadomorpha): Aquatic and Aerial Respiration

1974 ◽  
Vol 61 (2) ◽  
pp. 309-320
Author(s):  
J. A. PETERSEN ◽  
H. J. FYHN ◽  
K. JOHANSEN
Keyword(s):  
Gas Exchange ◽  
Oxygen Uptake ◽  
Laboratory Experiments ◽  
Air Exposure ◽  
Pollicipes Polymerus ◽  
Respiratory Parameters ◽  
Ambient Oxygen ◽  
Hypoxic Water ◽  
Increasing Temperature ◽  
Cutaneous Respiration

1. Gas exchange in water and in air of the intertidal cirriped Pollicipes polymerus has been studied by combined field and laboratory experiments. 2. Haemolymph gas tensions and pH are correlated with the tidal cycle in the field. Air exposure is accompanied by increasing oxygen and carbon dioxide tensions, and by decreasing haemolymph pH. During resubmersion the respiratory parameters are restored to values typical of the submerged state. There is no accumulation of lactic acid during air exposure. 3. The oxygen uptake of Pollicipes is higher for air exposed than for submerged animals at each tested temperature. In air exposed animals the oxygen uptake shows a decreasing Q10 with increasing temperature between 2 and 27 °C. Pollicipes exhibits oxygen conformity under varying ambient oxygen tensions and no oxygen debt is found after exposure to hypoxic water. 4. The peduncle cuticle is permeable to oxygen and cutaneous respiration at this level may contribute significantly to the overall oxygen uptake. 5. Pollicipes is well adapted to respiratory gas exchange both in water and in air making it a successful species in the intertidal community.

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.

Oxygen uptake in air and water in the air-breathing reedfish Calamoichthys calabaricus: role of skin, gills and lungs

1982 ◽  
Vol 97 (1) ◽  
pp. 179-186
Author(s):  
R. Sacca ◽  
W. Burggren
Keyword(s):  
Gas Exchange ◽  
Oxygen Uptake ◽  
Natural Environment ◽  
Average Duration ◽  
O2 Uptake ◽  
Total Oxygen ◽  
Air Exposure ◽  
Air Breathing

The reedfish Calamoichthys calabaricus (Smith) is amphibious, making voluntary excursions on to land (in a simulated natural environment) an average of 6 +/− 4 times/day for an average duration of 2.3 +/− 1.3 min. Oxygen uptake is achieved by the gills, skin and large, paired lungs. In water at 27 degrees C, total oxygen uptake is 0.088 ml O2/g.h. The lungs account for 40%, the gills 28%, and the skin 32% of total VO2. Total oxygen uptake during 2 h of air exposure increases from 0.117 ml O2/g.h to 0.286 ml O2/g.h, due largely to an enhanced lung VO2 and a small increase in skin VO2. Calamoichthys is both capable of aerial gas exchange and adapted to maintain O2 uptake during brief terrestrial excursions.

scholarly journals Fish heating tolerance scales similarly across individual physiology and populations

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Nicholas L. Payne ◽  
Simon A. Morley ◽  
Lewis G. Halsey ◽  
James A. Smith ◽  
Rick Stuart-Smith ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Tropical Species ◽  
Acclimation Temperature ◽  
Tight Coupling ◽  
Abundance Patterns ◽  
Biological Responses ◽  
In The Wild ◽  
Demographic Processes ◽  
Climate Vulnerability ◽  
Increasing Temperature

AbstractExtrapolating patterns from individuals to populations informs climate vulnerability models, yet biological responses to warming are uncertain at both levels. Here we contrast data on the heating tolerances of fishes from laboratory experiments with abundance patterns of wild populations. We find that heating tolerances in terms of individual physiologies in the lab and abundance in the wild decline with increasing temperature at the same rate. However, at a given acclimation temperature or optimum temperature, tropical individuals and populations have broader heating tolerances than temperate ones. These congruent relationships implicate a tight coupling between physiological and demographic processes underpinning macroecological patterns, and identify vulnerability in both temperate and tropical species.

Pulmonary Gas Exchange and Oxygen Uptake During Exercise in Patients with Type 1 Diabetes Mellitus

1992 ◽  
Vol 9 (3) ◽  
pp. 252-257 ◽  
Author(s):  
Th. Wanke ◽  
D. Formanek ◽  
M. Auinger ◽  
H. Zwick ◽  
K. Irsigler
Keyword(s):  
Diabetes Mellitus ◽  
Type 1 Diabetes ◽  
Gas Exchange ◽  
Oxygen Uptake ◽  
Type 1 Diabetes Mellitus ◽  
Pulmonary Gas Exchange

scholarly journals Formation of C-A-S-H phases from the interaction between concrete or cement and bentonite

Clay Minerals ◽  
2016 ◽  
Vol 51 (2) ◽  
pp. 223-235 ◽  
Author(s):  
Raúl Fernández ◽  
Ana Isabel Ruiz ◽  
Jaime Cuevas
Keyword(s):  
Calcium Silicate Hydrate ◽  
Laboratory Experiments ◽  
Pore Scale ◽  
Lime Mortar ◽  
Cement Interface ◽  
Argillaceous Rocks ◽  
Deep Geological Disposal ◽  
Engineered Barriers ◽  
High Level ◽  
Increasing Temperature

AbstractConcrete and bentonite are being considered as engineered barriers for the deep geological disposal of high-level radioactive waste in argillaceous rocks. Three hydrothermal laboratory experiments of different scalable complexity were performed to improve our knowledge of the formation of calcium aluminate silicate hydrates (C-A-S-H) at the interface between the two materials: concretebentonite transport columns, lime mortar-bentonite transport columns and a portlandite- (bentonite and montmorillonite) batch experiment. Precipitation of C-A-S-H was observed in all experiments. Acicular and fibrous morphologies with certain laminar characteristics were observed which had smaller Ca/Si and larger Al/Si ratios with increasing temperature and lack of accessory minerals. The compositional fields of these C-A-S-H phases formed in the experiments are consistent with Al/(Si+Al) ratios of 0.2– 0.3 described in the literature. The most representative calcium silicate hydrate (C-S-H) phase from the montmorillonite–cement interface is Al-tobermorite. Structural analyses revealed a potential intercalation or association of montmorillonite and C-A-S-H phases at the pore scale.

scholarly journals Laboratory experiments on CO2 gas exchange with wave breaking

2020 ◽  
Author(s):  
shuo li ◽  
Alexander V. Babanin ◽  
Fangli Qiao ◽  
Dejun Dai ◽  
Shumin Jiang ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Wave Breaking ◽  
Laboratory Experiments ◽  
Co2 Gas ◽  
Co2 Gas Exchange

scholarly journals Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers

1996 ◽  
Vol 81 (5) ◽  
pp. 1901-1907 ◽  
Author(s):  
Roland Favier ◽  
Esperanza Caceres ◽  
Laurent Guillon ◽  
Brigitte Sempore ◽  
Michel Sauvain ◽  
...  
Keyword(s):  
Heart Rate ◽  
Gas Exchange ◽  
Oxygen Uptake ◽  
Metabolic Responses ◽  
Physiological Data ◽  
Respiratory Gas Exchange ◽  
Gum Chewing ◽  
Arterial Blood ◽  
Before And After ◽  
Exercise Induced

Favier, Roland, Esperanza Caceres, Laurent Guillon, Brigitte Sempore, Michel Sauvain, Harry Koubi, and Hilde Spielvogel. Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers. J. Appl. Physiol. 81(5): 1901–1907, 1996.—To determine the effects of acute coca use on the hormonal and metabolic responses to exercise, 12 healthy nonhabitual coca users were submitted twice to steady-state exercise (∼75% maximal O2 uptake). On one occasion, they were asked to chew 15 g of coca leaves 1 h before exercise, whereas on the other occasion, exercise was performed after 1 h of chewing a sugar-free chewing gum. Plasma epinephrine, norepinephrine, insulin, glucagon, and metabolites (glucose, lactate, glycerol, and free fatty acids) were determined at rest before and after coca chewing and during the 5th, 15th, 30th, and 60th min of exercise. Simultaneously to these determinations, cardiorespiratory variables (heart rate, mean arterial blood pressure, oxygen uptake, and respiratory gas exchange ratio) were also measured. At rest, coca chewing had no effect on plasma hormonal and metabolic levels except for a significantly reduced insulin concentration. During exercise, the oxygen uptake, heart rate, and respiratory gas exchange ratio were significantly increased in the coca-chewing trial compared with the control (gum-chewing) test. The exercise-induced drop in plasma glucose and insulin was prevented by prior coca chewing. These results contrast with previous data obtained in chronic coca users who display during prolonged submaximal exercise an exaggerated plasma sympathetic response, an enhanced availability and utilization of fat (R. Favier, E. Caceres, H. Koubi, B. Sempore, M. Sauvain, and H. Spielvogel. J. Appl. Physiol. 80: 650–655, 1996). We conclude that, whereas coca chewing might affect glucose homeostasis during exercise, none of the physiological data provided by this study would suggest that acute coca chewing in nonhabitual users could enhance tolerance to exercise.

scholarly journals Effect of Process Parameters on Catalytic Incineration of Solvent Emissions

2008 ◽  
Vol 2008 ◽  
pp. 1-7 ◽  
Author(s):  
Satu Ojala ◽  
Ulla Lassi ◽  
Paavo Perämäki ◽  
Riitta L. Keiski
Keyword(s):  
Laboratory Experiments ◽  
Butyl Acetate ◽  
Space Velocity ◽  
Optimal Operation ◽  
Process Conditions ◽  
Statistical Experimental Design ◽  
Operation Conditions ◽  
A Minor ◽  
Increasing Temperature ◽  
By Products

Catalytic oxidation is a feasible and affordable technology for solvent emission abatement. However, finding optimal operation conditions is important, since they are strongly dependent on the application area of VOC incineration. This paper presents the results of the laboratory experiments concerning four most central parameters, that is, effects of concentration, gas hourly space velocity (GHSV), temperature, and moisture on the oxidation of n-butyl acetate. Both fresh and industrially aged commercial Pt/Al2O3catalysts were tested to determine optimal process conditions and the significance order and level of selected parameters. The effects of these parameters were evaluated by computer-aided statistical experimental design. According to the results, GHSV was the most dominant parameter in the oxidation of n-butyl acetate. Decreasing GHSV and increasing temperature increased the conversion of n-butyl acetate. The interaction effect of GHSV and temperature was more significant than the effect of concentration. Both of these affected the reaction by increasing the conversion of n-butyl acetate. Moisture had only a minor decreasing effect on the conversion, but it also decreased slightly the formation of by products. Ageing did not change the significance order of the above-mentioned parameters, however, the effects of individual parameters increased slightly as a function of ageing.

scholarly journals The Circulatory Response to Acute Hypoxia in Octopus

1983 ◽  
Vol 104 (1) ◽  
pp. 59-71 ◽  
Author(s):  
M.J. WELLS ◽  
J. WELLS
Keyword(s):  
Oxygen Uptake ◽  
Acute Hypoxia ◽  
Oxygen Affinity ◽  
Octopus Vulgaris ◽  
Blood Oxygen ◽  
Total Oxygen ◽  
Circulatory Response ◽  
The Central Nervous System ◽  
Blood Oxygen Affinity ◽  
Cutaneous Respiration

Octopus vulgaris can regulate its oxygen uptake in a closed respirometer down to a Poo2 of less than 70 mmHg. As the tankwater Poo2 falls the hearts slow down. Pulse amplitudes and mean pressures fall in the afferent branchial vessels and in the dorsal aorta. Despite behavioural changes - expansion of the interbrachial web and extension of the arms - that might imply this, the proportion of the total oxygen uptake attributable to cutaneous respiration (less than 13%) does not alter as the external Poo2 falls. The response of the hearts to a low Poo2 is not affected by severing the nerve supply from the central nervous system, or by removal of the heart ganglia. It is evidently determined by oxygen lack and not by the accumulation of CO2 or other metabolites, since the same effects are achieved by placing the animals in water where the Poo2 has been reduced by boiling. The conclusion that regulation does not depend upon circulatory responses to hypoxia is considered in the light of recent work on the changes in blood oxygen affinity associated with acute hypoxia in cephalopods.

Respiration in the African Lungfish Protopterus Aethiopicus

1968 ◽  
Vol 49 (2) ◽  
pp. 437-452 ◽  
Author(s):  
CLAUDE LENFANT ◽  
KJELL JOHANSEN
Keyword(s):  
Gas Exchange ◽  
Haemoglobin Concentration ◽  
Temperature Shift ◽  
Mean Value ◽  
Gas Analysis ◽  
Air Exposure ◽  
Air Breathing ◽  
African Lungfish ◽  
High Degree ◽  
Protopterus Aethiopicus

1. Respiratory properties of blood and pattern of aerial and aquatic breathing and gas exchange have been studied in the African lungfish, Protopterus aethiopicus. 2. The mean value for haematocrit was 25%. Haemoglobin concentration was 6.2 g% and O2 capacity 6.8 vol. %. 3. The affinity of haemoglobin for O2 was high. P50 was 10 mm. Hg at PCOCO2, 6 mm. Hg and 25 °C. The Bohr effect was smaller than for the Australian lungfish, Neoceratodus, but exceeded that for the South American lungfish, Lepidosiren. The O2 affinity showed a larger temperature shift in Protopterus than Neoceratodus. 4. The CO2 combining power and the over-all buffering capacity of the blood exceeded values for the other lungfishes. 5. Both aerial and aquatic breathing showed a labile frequency. Air exposure elicited a marked increase in the rate of air breathing. 6. When resting in aerated water, air breathing accounted for about 90% of the O2 absorption. Aquatic gas exchange with gills and skin was 2.5 times more effective than pulmonary gas exchange in removing CO2. The low gas-exchange ratio for the lung diminished further in the interval between breaths. 7. Protopterus showed respiratory independence and a maintained O2 uptake until the ambient O2 and CO2 tensions were 85 and 35 mm. Hg respectively. A further reduction in O2 tension caused an abrupt fall in the oxygen uptake. 8. Gas analysis of blood samples drawn from unanaesthetized, free-swimming fishes attested to the important role of the lung in gas exchange and the high degree of functional separation in the circulation of oxygenated and deoxygenated blood.

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