scholarly journals Aedes Aegypti: Energetics of Osmoregulation

1982 ◽  
Vol 101 (1) ◽  
pp. 135-141 ◽  
Author(s):  
H.A. EDWARDS
Keyword(s):  
Oxygen Consumption ◽  
Energy Cost ◽  
Sea Water ◽  
External Medium ◽  
Minimum Energy ◽  
Body Volume ◽  
Wet Weight ◽  
Minimum Energy Cost ◽  
Anal Papillae ◽  
Theoretical Minimum

1. Oxygen consumption of A. aegypti larvae, about 210 mul l g−1 tissue wet weight h−1, does not change when the salinity of the environment is changed. The number of mitochondria in the anal papillae, a salt-absorbing epithelium, increases as the external medium is diluted. There is no difference in oxygen consumption between isolated anal papillae in 0, 2 and 20% sea water. The papillae represent about 5% of body volume and their oxygen consumption is about 2% of the animal's total. The theoretical minimum energy cost of osmoregulation is four orders of magnitude smaller than the measured figure for the anal papillae alone. Osmoregulatory phenomena which would explain the recorded observations are discussed.

Minimum Energy Cost Broadcasting in Wireless Networks

2016 ◽  
pp. 1308-1312
Author(s):  
Peng-Jun Wan ◽  
Xiang-Yang Li ◽  
Ophir Frieder
Keyword(s):  
Wireless Networks ◽  
Energy Cost ◽  
Minimum Energy ◽  
Minimum Energy Cost

Osmotic balance and respiration in the hermit crab, Pagurus bernhardus, exposed to fluctuating salinities

1978 ◽  
Vol 58 (4) ◽  
pp. 869-876 ◽  
Author(s):  
Sandra E. Shumway
Keyword(s):  
Oxygen Consumption ◽  
Sea Water ◽  
External Medium ◽  
Temporary Increase ◽  
Tissue Water ◽  
Low Salinity ◽  
Significant Difference ◽  
Rate Of Oxygen Consumption ◽  
Osmotic Balance ◽  
Pagurus Bernhardus

Specimens of Pagurus bernhardus (with and without shells) were exposed to both gradual (sinusoidal) and abrupt (square-wave) salinity fluctuations and changes in haemolymph osmolality, tissue water content and oxygen consumption monitored. Oxygen consumption was also monitored under steady-state conditions; under these conditions there was no significant difference between the rate of oxygen consumption by animals with shells and animals without shells. Oxygen consumption was found to vary with body weight according to the equation O2 consumption = 0·292 W0·668. During exposure to fluctuating salinities the crabs with shells were seen to increase loco-motory activity when the external medium declined to approximately 75% sea water. Haemolymph osmolality values followed the same pattern of change as the external medium; the haemolymph of crabs without shells became significantly more dilute during exposure to low salinity than did that of crabs with shells. P. bernhardus showed significant increases and decreases in hydration level as salinities fell and rose respectively. Crabs with shells showed a marked temporary increase in oxygen consumption when the external medium declined to approximately 75% sea water; crabs without shells showed no such response. The importance of the shell as a means of protection against dilute media is discussed.

Upper bound of the minimum energy cost for controlling complex networks

2019 ◽  
Author(s):  
Gaopeng Duan ◽  
Aming Li ◽  
Tao Meng ◽  
Guofeng Zhang ◽  
Long Wang
Keyword(s):  
Complex Networks ◽  
Upper Bound ◽  
Energy Cost ◽  
Minimum Energy ◽  
Minimum Energy Cost

scholarly journals Real-time monitoring of the prototype design of electric system by the ubidots platform

2021 ◽  
Vol 11 (6) ◽  
pp. 5568
Author(s):  
Noor Saleh Mohammed ◽  
Nasir Hussein Selman
Keyword(s):  
Energy Cost ◽  
High Reliability ◽  
Minimum Energy ◽  
Electricity Consumption ◽  
Operating Mode ◽  
Electric System ◽  
Visualization Analysis ◽  
Network State ◽  
Minimum Energy Cost ◽  
Prototype Design

<span>In this paper, a prototype DC electric system was practically designed. The idea of the proposed system was derived from the microgrid concept. The system contained two houses each have a DC generator and load that consists of four 12 V DC lamps. Each house is controlled fully by Arduino UNO microcontroller to work in Island mode or connected it with the second house or main electric network. House operating mode depends on the power generated by its source and the availability of the main network. Under all operating cases, the minimum price of electricity consumption should satisfy as possible. Information between the houses about the operating mode and the main network state was exchanging wirelessly with the help of the RF-HC12. This information uploaded to the Ubidots platform by the Wi-Fi-ESP8266 included in the node MCU microcontroller. This platform has several advantages such as capture, visualization, analysis, and management of data. The system was examined for different cases to verify its working by varying the load in each building. All tested states showed that the houses transfer from one mode to another automatically with high reliability and minimum energy cost. The information about the main grid states and the sources of the houses were monitored and stored at the Ubidots platform.</span>

The Physiology of Contractile Vacuoles

1948 ◽  
Vol 25 (4) ◽  
pp. 421-436
Author(s):  
J. A. KITCHING
Keyword(s):  
Osmotic Pressure ◽  
Sea Water ◽  
External Medium ◽  
External Solution ◽  
Pond Water ◽  
The Body ◽  
Contractile Vacuole ◽  
Effect Of Temperature ◽  
Body Volume ◽  
Sucrose Solutions

1. On transfer from sea water to dilute sea water, the marine peritrich ciliate Vorticella marina swells more rapidly at higher temperatures. 2. It is concluded that the permeability of the surface of V. marina to water is influenced by temperature, with a Q10 of very roughly 2·5-3·2. 3. The body volume of the fresh-water peritrich ciliate Carchesium aselli is maintained approximately constant when the organism is transferred to solutions of sucrose of concentrations up to about 0·04 M; in higher concentrations the organism shrinks. 4. The rate of output of the contractile vacuole of C. aselli decreases with increasing concentrations of sucrose in the external medium; the rate of output is very low in 0·05 M-sucrose. 5. From a consideration of the effects of sucrose solutions on the body volume and on the rate of vacuolar output it is concluded that the initial osmotic pressure of C. aselli normally exceeds that of the external pond water by about 0·04-0·05 M non-electrolyte. 6. The internal osmotic pressure of C. aselli is not materially increased by increase of temperature. 7. It is concluded that the increase in rate of vacuolar output, which accompanies increase of temperature, counterbalances an increased rate of osmotic uptake of water from the external medium, and that this increased rate of uptake is due to an effect of temperature on the permeability of the surface through which the water enters. 8. The rate of vacuolar output is temporarily much increased when C. aselli, which has been equilibrated in solutions of ethylene glycol, is returned to pond water. 9. It is suggested that the temperature and the osmotic pressure of the external solution largely determine the osmotic stress which is imposed on the organism, and that they thus influence the state of hydration of the protoplasm; in turn this may be supposed to determine the activity of the contractile vacuole.

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