The Respiratory Physiology of the Marine Nematodes Enoplus Brevis (Bastian) and E. Communis (Bastian)

1973 ◽  
Vol 59 (1) ◽  
pp. 255-266
Author(s):  
H. J. ATKINSON
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Oxygen Tension ◽  
Dry Weight ◽  
Respiratory Physiology ◽  
Rate Of Oxygen Consumption ◽  
Oxygen Tensions ◽  
The Difference ◽  
Relationship Of ◽  
The Relationship

1. The rate of oxygen consumption of individual males of Enoplus brevis and E. communis was measured at 15 °C and at each of four oxygen tensions, 135, 75, 35, and 12 Torr, after at least 12 h experience of these conditions. 2. It was clearly demonstrated that the level of oxygen consumption of both species was reduced by each lowering of the imposed oxygen tension. 3. In all cases the oxygen consumption of each species fell with increasing body size. On a unit dry-weight basis the oxygen consumption of E. brevis is greater than that of the larger E. communis, but after allowing for the difference of body size the two species have more or less similar oxygen uptakes at all oxygen tensions. 4. In E. brevis oxygen tension influenced the relationship of body size and metabolism, the slope relating oxygen consumption and body weight becomes steeper with decreasing oxygen tension. This effect was not shown by E. communis. 5. Some general factors influencing the availability of oxygen to nematodes are considered.

scholarly journals Oxygen Consumption and Cell Size. A Comparison of the Rate of Oxygen Consumption of Diploid and Triploid Prepupae of Drosophila Melanogaster Meigen

1953 ◽  
Vol 30 (4) ◽  
pp. 475-491 ◽  
Author(s):  
C. ELLENBY
Keyword(s):  
Body Weight ◽  
Drosophila Melanogaster ◽  
Oxygen Consumption ◽  
Body Size ◽  
Surface Area ◽  
Cell Size ◽  
Rate Of Oxygen Consumption ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship

1. The oxygen consumption and surface area of individual diploid and triploid prepupae of Drosophila melanogaster have been measured, the cells of triploid animals being larger. 2. The mean weights for the types examined are different but their ranges overlap almost completely. By covariance analysis it is shown that, after adjustment for difference in body size, there are no differences in the rates of oxygen consumption. It is concluded that, for these animals, cell size has no influence on the rate of oxygen consumption. 3. The relationships between body weight, surface area, and oxygen consumption have been further investigated. It is shown that, despite the greater inaccuracy of the method by which surface area is determined, oxygen consumption can be predicted more accurately from surface area than from body weight. 4. The results are discussed in relation to an earlier investigation of the oxygen consumption of other genotypes (Ellenby, 1945 a, b). Possible technical causes of certain differences between the two series of results in the relationship of oxygen consumption and body weight are explored; it is concluded, however, that they are almost certainly due to differences, not necessarily genetical, between the animals used in the two series.

scholarly journals Body Size in Relation to Oxygen Consumption and Pleopod Beat in Ligia Oceanica L

1951 ◽  
Vol 28 (4) ◽  
pp. 492-507 ◽  
Author(s):  
C. ELLENBY
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
Body Size ◽  
Body Length ◽  
Body Shape ◽  
Size Range ◽  
Total Oxygen ◽  
Rate Of Oxygen Consumption ◽  
Relationship Of ◽  
The Relationship

1. Male Ligia oceanica were used in an investigation of the relationship of body size to rate of oxygen consumption and pleopod beat. 2. Animals varied in weight from 0.04 to 1.03 g. and from 0.95 to 3.1 cm. in length. 3. Body shape does not change significantly over the size range, for length and breadth both increase at the same rate, and pleopod dimensions bear a constant relation to body length. 4. Specific gravity also is constant, for the relation of body weight to the cube of body length shows no trend with increasing size. 5. Oxygen consumption per gram decreases with increasing size and is proportional to the -0.274 Power of body weight. Total oxygen consumption is therefore proportional to the 0.726 power of body weight; but this value does not differ significantly from two-thirds. 6. As shape is constant, surface area is proportional to the square of a linear dimension. It is shown that oxygen consumption per unit of length2 is constant over the size range. Although body length was measured far less accurately than body weight it is shown that it assesses ‘body size’ more accurately. 7. Rate of pleopod beat was measured at 15 and 25°C.; it decreases with the size of the animal. At 15°C. time per beat varies as the 0.66 power of body length, and at 25°C. as the 0.59 power; neither of these values differs significantly from 0.5. Despite the fact that pleopod movement is heavily damped, the rate therefore varies like that of a pendulum. 9. The workof Fox (1936-9) and Fox et al. (1937a)on the rate of oxygen consumption of animals from cold and warmer seas and from different habitats is considered. It is suggested that many of their comparisons are invalidated by differences in body size of the animals concerned, and that, in relation to environment, no basis, theoretical or experimental, has been established for a distinction between ‘nonlocomotory’ and ‘activity’ metabolism.

The Oxygen Consumption of an Echiuroid, Bonellia Viridis Rolando

1968 ◽  
Vol 48 (2) ◽  
pp. 427-434
Author(s):  
A. E. BRAFIELD
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Continuous Flow ◽  
Muscular Activity ◽  
Dry Weight ◽  
The Body ◽  
Body Region ◽  
Rate Of Oxygen Consumption

1. The oxygen consumption of the echiuroid Bonellia viridis has been investigated by means of a continuous-flow polarographic respirometer. 2. The general rate of oxygen consumption per unit dry weight is similar to that characteristic of polychaetes, and declines exponentially with increasing body size. 3. The rate of oxygen consumption rises in the light and falls again if darkness is restored. 4. The oxygen consumption of the isolated proboscis plus that of the isolated body region corresponds closely to that of the entire animal. 5. The oxygen consumption per unit dry weight of the proboscis is considerably higher than that of the body region. 6. The oxygen consumption of an isolated body region increases in the presence of light, but that of an isolated proboscis does not. 7. These findings are discussed in relation to the biology of the animal, observed muscular activity, and the occurrence of the pigment bonellin.

The Relation of Oxygen Consumption to Body Size and to Temperature in the Larvae of Chironomus Riparius Meigen

1958 ◽  
Vol 35 (2) ◽  
pp. 383-395
Author(s):  
R. W. EDWARDS
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Dry Matter ◽  
Larval Instar ◽  
Weight Ratio ◽  
Dry Weight ◽  
Chironomus Riparius ◽  
Consumption Rates ◽  
Rate Of Oxygen Consumption ◽  
Wet Weight

1. The oxygen consumption rates of 3rd- and 4th-instar larvae of Chironomus riparius have been measured at 10 and 20° C. using a constant-volume respirometer. 2. The oxygen consumption is approximately proportional to the 0.7 power of the dry weight: it is not proportional to the estimated surface area. 3. This relationship between oxygen consumption and dry weight is the same at 10 and at 20° C.. 4. The rate of oxygen consumption at 20° C. is greater than at 10° C. by a factor of 2.6. 5. During growth the percentage of dry matter of 4th-instar larvae increases from 10 to 16 and the specific gravity from 1.030 to 1.043. 6. The change in the dry weight/wet weight ratio during the 4 larval instar supports the theory of heterauxesis. 7. At 20° C., ‘summer’ larvae respire faster than ‘winter’ larvae.

Critical oxygen tensions in newborn, young, and adult mice

1963 ◽  
Vol 205 (2) ◽  
pp. 325-330 ◽  
Author(s):  
S. Cassin
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Tension ◽  
Environmental Temperature ◽  
Mild Hypothermia ◽  
Newborn Mouse ◽  
Newborn Mice ◽  
Adult Mice ◽  
Critical Oxygen ◽  
Rate Of Oxygen Consumption ◽  
Oxygen Tensions

Critical oxygen tensions of newborn, young, and adult mice are presented. At neutral environmental temperature, oxygen consumption of newborn mice is unaffected by reducing the oxygen tension of inspired air to 85 mm Hg. Five-day-old mice, at neutral environmental temperature, tolerate a decrease in ambient oxygen tension to 100 mm Hg without a depression of oxygen consumption. Adult mice behave in a qualitatively similar fashion. When the ambient temperature is lowered below neutral, the mice are unable to maintain a constant oxygen consumption if hypoxia is induced. It appears as though the depression of oxygen consumption during hypoxia is linearly related to the hypothermic increment to metabolism: the greater the extra oxygen consumption, the more readily it is reduced. Although the newborn mouse is unable to combat hypothermia effectively, it does respond to mild hypothermia for short periods by increasing its rate of oxygen consumption. Evidence is presented of a rapid maturation of temperature controlling mechanisms during growth.

The Respiratory Physiology of the Marine Nematodes Enoplus Brevis (Bastian) and E. Communis (Bastian)

1973 ◽  
Vol 59 (1) ◽  
pp. 267-274
Author(s):  
H. J. ATKINSON
Keyword(s):  
Oxygen Consumption ◽  
Sea Water ◽  
Atmospheric Oxygen ◽  
Respiratory Physiology ◽  
Marine Nematodes ◽  
Oxygen Regime ◽  
Lower Oxygen ◽  
Rate Of Oxygen Consumption ◽  
Oxygen Tensions ◽  
Oxygen Requirements

1. The rate of oxygen consumption of individual male Enoplus brevis and E. communis was measured at 15 °C, after altering the oxygen regime experienced since the animals were collected. 2. When both E. brevis and E. communis were transferred to 35 Torr from atmospheric oxygen tensions, their oxygen consumption was only two-thirds of that of individuals maintained at this lower oxygen tension. 3. The rate of oxygen consumption of the two species at 135 Torr was unaltered by exposure for 2 h to oxygen-free sea water. 4. The results are discussed in relation to the overall influence of fluctuating oxygen regimes on the oxygen requirements of nematodes.

Energy expenditure by elite midget male ice hockey players in small-sided games

2017 ◽  
Vol 12 (4) ◽  
pp. 504-513 ◽  
Author(s):  
Charles-Mathieu Lachaume ◽  
François Trudeau ◽  
Jean Lemoyne
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Energy Expenditure ◽  
Ice Hockey ◽  
Training Method ◽  
Hockey Players ◽  
Treadmill Testing ◽  
Effective Training ◽  
Relationship Of ◽  
The Relationship

The purpose of this study was to investigate the energy expenditure and heart rate responses elicited in elite male midget ice hockey players during small-sided games. Nine players (aged 15.89 ± 0.33 years) participated in the study. Maximal progressive treadmill testing in the laboratory measured the relationship of oxygen consumption ([Formula: see text]) to heart rate before on-ice assessments of heart rate during six different small-sided games: 1v1, 2v2, 2v2 with support player, 3v3 with support player, 3v3 with transitions, and 4v4 with two support players. Heart rate was recorded continuously in each game. 3v3 T small-sided game was the most intense for all four intensity markers. All six small-sided games reached 89% HRmax or more with heart rate peaks in active effort repetition. These findings demonstrate that such small-sided games are considered as high intensity games and are an effective training method for ice hockey players.

The Performance of Sailing Yachts in Oblique Seas

1974 ◽  
Vol 11 (04) ◽  
pp. 383-392
Author(s):  
David R. Pedrick
Keyword(s):  
Wave Length ◽  
Added Resistance ◽  
Regular Waves ◽  
Sea State ◽  
Hull Form ◽  
Rough Water ◽  
Rational Procedure ◽  
The Difference ◽  
Relationship Of ◽  
The Relationship

The difference in the effects of rough water on similar sailing yachts has been one of the intriguing puzzles that sailors, designers, and researchers have long tried to understand. It is not uncommon for two yachts of equal performance in smooth-sea conditions to have their speed or pointing ability reduced by different amounts when encountering waves. To investigate the causes of such behavior, it is important to have a rational procedure to analyze how changes in hull form, weight distribution, rig, and other design features affect the speed and motions of sailing yachts. This paper discusses the relationship of wind to rough water and of motions and added resistance to wave length and height. It then describes a procedure to predict motions, sailing speed, and speed-made-good to windward in realistic windward sailing conditions. The procedure utilizes results of heeled and yawed model tests of 12-metre yachts in oblique regular waves to predict performance in a Pierson-Moskowitz sea state corresponding closely to the equilibrium true wind speed.

Sign in / Sign up

Export Citation Format

Share Document