THE OSMOREGULATORY ROLE OF THE THYROID GLAND IN THE STARRY FLOUNDER, PLATICHTHYS STELLATUS

1959 ◽  
Vol 37 (6) ◽  
pp. 997-1060 ◽  
Author(s):  
Cleveland P. Hickman Jr.
Keyword(s):  
Thyroid Gland ◽  
Fresh Water ◽  
Body Fluid ◽  
Sea Water ◽  
Salt Water ◽  
Standard Metabolic Rate ◽  
Energy Demands ◽  
Platichthys Stellatus ◽  
Fluid Concentration

Energy demands for osmotic regulation and the possible osmoregulatory role of the thyroid gland were investigated in the euryhaline starry flounder, Platichthys stellatus. Using a melting-point technique, it was established that flounder could regulate body fluid concentration independently of widely divergent environmental salinities. Small flounder experienced more rapid disturbances of body fluid concentration than large flounder after abrupt salinity alterations.The standard metabolic rate of flounder adapted to fresh water was consistently and significantly less than that of marine flounder. In supernormal salinities standard metabolic rate was significantly greater than in normal sea water. These findings agree with the theory that energy demands for active electrolyte transport are greater in sea water than fresh water.Thyroid activity was studied in flounder adapted to fresh water and salt water. Percentage uptake of radioiodine by the thyroid was shown to be an insensitive and inaccurate criterion for evaluating thyroid activity in different salinities because removal rates of radioiodine from the body and blood differed between fresh water and marine flounder. Using thyroid clearance of radioiodine from the blood as a measure of activity, salt-water flounder were shown to have much greater thyroid clearance rates and, hence, more active thyroid glands than flounder adapted to fresh water. The greater activity of the thyroid of marine flounder correlates with greater oxygen demands in sea water and suggests a direct or adjunctive osmoregulatory role of the thyroid gland of fish.

scholarly journals KEMISKINAN DI WILAYAH PEDESAAN NTB : STUDI KASUS WANITA PEMBUAT GARAM DI DUSUN MEDANG

Agro Ekonomi ◽  
2016 ◽  
Vol 9 (1) ◽  
pp. 65
Author(s):  
Maryadi Maryadi
Keyword(s):  
Sea Water ◽  
Salt Water ◽  
Poverty Line ◽  
Small Scale ◽  
Salty Water ◽  
Processing Material ◽  
Home Industries ◽  
Rural Industries ◽  
Small Scale Industries

Role of women in development has been well-known. Women roles in rural area can be identified from their involvement in rural industries either agricultural home industries or other small-scale industries processing material taken from natural resources. One of such natural resource materials is sea water to be further processed as salts. Most of women in Medang Hamlet, Village of Sekotong Barat, Nusa Tenggara Barat Province work as salt makers. Instead of drying salty water by using sunshine, the salt farmers in Medang Hamlet use wood in heating the salt water. The study finds that the income earned from this activity is considerably low. Since there is no other source of income alternative for the women in this hamlet, making salt becomes the only job that can be done. The consequence is that the villagers in this area are still live under poverty line.

The evolution of under-ice melt ponds, or double diffusion at the freezing point

1974 ◽  
Vol 64 (3) ◽  
pp. 507-528 ◽  
Author(s):  
Seelye Martin ◽  
Peter Kauffman
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Freezing Point ◽  
Salt Water ◽  
Ice Sheet ◽  
Water Layer ◽  
Double Diffusion ◽  
Theoretical Models ◽  
Interfacial Region ◽  
Ice Melt

In an experimental and theoretical study, we model a phenomenon observed in the summer Arctic, where a fresh-water layer at a temperature of 0°C floats both over a sea-water layer at its freezing point and under an ice layer. Our results show that the ice growth in this system takes place in three phases. First, because the fresh-water density decreases upon supercooling, the rapid diffusion of heat relative to salt from the fresh to the salt water causes a density inversion and thereby generates a high Rayleigh number convection in the fresh water. In this convection, supercooled water rises to the ice layer, where it nucleates into thin vertical interlocking ice crystals. When these sheets grow down to the interface, supercooling ceases. Second, the presence of the vertical ice sheets both constrains the temperatureTand salinitysto lie on the freezing curve and allows them to diffuse in the vertical. In the interfacial region, the combination of these processes generates a lateral crystal growth, which continues until a horizontal ice sheet forms. Third, because of theTandsgradients in the sea water below this ice sheet, the horizontal sheet both migrates upwards and increases in thickness. From one-dimensional theoretical models of the first two phases, we find that the heat-transfer rates are 5–10 times those calculated for classic thermal diffusion.

Studies on Salt-Water and Fresh-Water Anopheles gambiae on the East African Coast

1951 ◽  
Vol 41 (3) ◽  
pp. 487-502 ◽  
Author(s):  
R. C. Muirhead Thomson
Keyword(s):  
West Africa ◽  
Fresh Water ◽  
Sea Water ◽  
Salt Water ◽  
Dar Es Salaam ◽  
Limiting Factor ◽  
East African ◽  
East African Coast ◽  
African Coast ◽  
Gravid Females

The brackish water form of A. gambiae on the East African coast—and probably in Mauritius—is not the same as A. melas of West Africa.In salt-water gambiae a variable proportion of the females have an additional dark band on the palps, resembling 4-banded melas, but the remainder are indistinguishable from typical gambiae.Eggs and larvae of salt-water gambiae show no morphological differences from those of fresh-water gambiae, thereby differing from A. melas of West Africa.Larvae of the two forms show a clear-cut difference in reaction to sudden changes in salinity, and a simple test has been worked out whereby wild-caught females can be accurately identified by the reactions of their progeny.This physiological test has formed the basis of all work in comparing the incidence, habits, and infectivity of salt and fresh-water gambiae in Dar-es-Salaam.Exposed to equal chances of infection in the same village during 1947 and 1948, fresh-water gambiae had a sporozoite rate of 9·4 per cent. while that of salt-water gambiae was 0·8 per cent.About 4 per cent, of both forms were infected with filaria larvae, but monthly figures showed that infection rates in salt-water gambiae may rise to 22 per cent.Fresh-water gambiae show little tendency to leave African houses at dawn after feeding, whereas in salt-water gambiae over one-third of freshly blood-fed females leave the house at dawn.In fresh-water gambiae many half-gravid females leave the shelter of the house at dusk on the night after the blood feed. There is no marked difference in infectivity between those which leave the hut and those which remain indoors at this stage.Blood-fed and gravid females of fresh-water gambiae, funestus, and salt-water gambiae have been found in outdoor resting places, gravid females predominating in the case of the first two.Although larvae of salt-water gambiae can complete their development in pure sea water, in nature increasing salinity becomes a limiting factor before it reaches that of sea water, continuous breeding being no longer possible at salinities over 83 per cent. sea water.Salinity as a limiting factor explains the rather restricted breeding of salt-water gambiae on the coast, and suggests that certain coastal fresh-water swamps at Dar-es-Salaam could be cleared of all Anopheline breeding by salinifying with sea water.

The effect of hypophysectomy and prolactin treatment on the osmotic water influx into the isolated gills of the Japanese eel (Anguilla japonica)

1977 ◽  
Vol 55 (5) ◽  
pp. 872-876 ◽  
Author(s):  
Mizuho Ogawa
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Anguilla Japonica ◽  
Japanese Eel ◽  
Osmotic Permeability ◽  
Water Influx ◽  
In Vitro Technique ◽  
Osmotic Water

An in vitro technique has been used to measure the osmotic water influx into the isolated gills and the osmotic permeability of the gill surface of the Japanese eel, Anguilla japonica. Hypophysectomy increases both of these measurements. Prolactin injections decrease both osmotic water influx and osmotic permeability to water in both the intact and hypophysectomized eels in fresh water but produce no change in either of these parameters when the fish (either intact or hypophysectomized) are in sea water. The possible role of the pituitary (especially prolactin) in osmoregulation of fishes is discussed and considered in relation to the environmental calcium in sea water.

scholarly journals The Adaptation of Mosquito Larvae to Salt Water

1933 ◽  
Vol 10 (1) ◽  
pp. 27-36 ◽  
Author(s):  
V. B. WIGGLESWORTH
Keyword(s):  
Basement Membrane ◽  
Fresh Water ◽  
Mosquito Larva ◽  
Sea Water ◽  
Salt Water ◽  
Physiological Adaptation ◽  
Mosquito Larvae ◽  
Salt Solutions ◽  
Newly Hatched Larvae

Larvae of Aedes argenteus reared in fresh water are killed by 1.1 per cent. NaCl or by "sea water"1 isotonic with 1.3-1.4 per cent. NaCl. Newly hatched larvae are killed by 1.1 per cent. NaCl or "sea water" equivalent to 1.3 per cent. NaCl. By gradually increasing the concentration, larvae can be made resistant to 1.1 per cent. NaCl and to "sea water" equivalent to 1.75 percent. NaCl (50 per cent. sea water). The nature of the physiological adaptation in these larvae has been studied and the following conclusions reached: 1. The elastic strands in the cells of the gills become exaggerated, and these cells resist swelling in hypertonic salt solutions. 2. There are changes in the epithelium of the mid-gut so that: (a) the cells are no longer caused to swell up and become detached from the basement membrane; and (b) the mid-gut and caeca can absorb the salt fluid and so avoid the excessive distension which occurs in unadapted larvae. 3. It is possible that the Malpighian tubes excrete a more concentrated urine and that the reabsorptive activity of the rectum is increased. The mosquito larva appears to be homoiosmotic in both fresh water and in hypertonic salt water.

The role of environmental calcium in freshwater survival of the marine teleost, Lagodon rhomboides

1976 ◽  
Vol 65 (3) ◽  
pp. 529-538
Author(s):  
J. C. Carrier ◽  
D. H. Evans
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Chelating Agent ◽  
Marine Teleost ◽  
Lagodon Rhomboides ◽  
Na Efflux ◽  
Total Body ◽  
Na Uptake ◽  
Marine Teleost Fish

(1) The marine teleost fish, Lagodon rhomboides, can only tolerate fresh water (5 mM Na) if Ca is also present (10 mM). Transfer to Ca-free fresh water is followed by a substantial increase in radioactive Na efflux with little or no change in the transepithelial potential. Addition of the chelating agent EDTA (2 mM) further increases Na efflux. Fish left in Ca-free fresh water for 2-5 h die with a total body Na less than 50% of that found in animals acclimated to Ca-supplemented fresh water. (2) Rates of Na uptake were measured on either sea-water-acclimated or Ca-supplemented fresh water-acclimated fish transferred to various low Na media. In both cases Na uptake has a high Km, is saturable, inhibited by external NH4, H and amiloride, and is not related to changes in the trans-epithelial potential. (3) It is suggested that L. rhomboides is dependent upon external Ca to decrease diffusional Na loss in low salinities so that a relatively inefficient Na uptake can balance diffusional and urinary Na loss.

Influence of salinity on ultrastructure of the secretory cells of the adenohypophyseal pars distalis in yearling coho salmon (Oncorhynchus kisutch)

1977 ◽  
Vol 55 (1) ◽  
pp. 183-198 ◽  
Author(s):  
Yoshitaka Nagahama ◽  
W. Craig Clarke ◽  
W. S. Hoar
Keyword(s):  
Freshwater Fish ◽  
Fresh Water ◽  
Coho Salmon ◽  
Sea Water ◽  
Salt Water ◽  
Light And Electron Microscopy ◽  
Secretory Cells ◽  
Plasma Sodium ◽  
Pars Distalis ◽  
Freshwater Environment

Six different types of secretory cells were identified by light and electron microscopy in the adenohypophyseal pars distalis of yearling coho salmon acclimated to fresh or salt water. Prolactin cells are markedly more active in the freshwater than the seawater fish; these cells exhibit definite functional activity 3 days after transfer from salt to fresh water, indicating an osmoregulatory role of prolactin in the freshwater environment. Plasma sodium showed a significant decline 6 h after transfer from sea water to fresh water and, even after 1 week, remained lower than in the fully acclimated freshwater fish. Corticotropic (ACTH) cells did not appear cytologically different in freshwater and seawater fish. GH cells, the most prominent cells in the proximal pars distalis, appear more numerous and more granulated in the seawater fish, suggesting an osmoregulatory involvement in young coho salmon. Putative thyrotropic (TSH) and putative gonadotropic cells (GTH) can be distinguished by differences in granulation; only one type of GTH cell is evident with ultrastructural features that differ from those of sexually mature salmon. Stellate, non-granulated cells occur in all regions of the adenohypophysis but more frequently in the prolactin follicles; they are much more prominent in the seawater than freshwater fish.

Lung changes and incidence of respiratory arrest in rats after aspiration of sea and fresh water

1961 ◽  
Vol 16 (1) ◽  
pp. 41-44 ◽  
Author(s):  
Denis F. J. Halmagyi
Keyword(s):  
Body Weight ◽  
Fresh Water ◽  
Sea Water ◽  
Salt Water ◽  
Respiratory Arrest ◽  
Fluid Administration ◽  
Lung Weight ◽  
Intratracheal Administration ◽  
Cervical Vagotomy

Some effects of intratracheal administration of 0.1 ml/100 gm body weight of fresh and sea water were studied in intact and vagotomized rats. No local changes were seen in the lungs after fresh water inhalation. A marked increase in lung weight and intra-alveolar hemorrhages developed following the aspiration of sea water. Fatal respiratory arrest occurred in some cases of salt water and cold fresh water inhalation. Bilateral cervical vagotomy prior to the intratracheal fluid administration failed to affect the incidence of respiratory arrest. Submitted on November 30, 1959

Investigating Effects of Graphene Nanoinclusions for Improved Desalination Rates of Salt Water Under Solar Heat

2018 ◽  
Author(s):  
Vinay Patil ◽  
Aybala Usta ◽  
Muhammad M. Rahman ◽  
Ramazan Asmatulu
Keyword(s):  
Fresh Water ◽  
Produced Water ◽  
Sea Water ◽  
Salt Water ◽  
Inorganic Compounds ◽  
Single Layer ◽  
Cost Effective ◽  
Hexagonal Shape ◽  
Water Problem ◽  
The Many

The development of sustainable, cost-effective, reliable, efficient and stable materials and methods for continuous fresh water production is crucial for many regions of the world. Among the many other options, graphene nanoflakes seem to be good option to solve the global water problem due to their low energy cost and simple operational process to purify waste water. The produced water can be used for drinking, agriculture, gardening, medical, industrial and other purposes. Most of the nanofilter-based multifunctional fresh water systems do not require large infrastructures or centralized systems, and can be portable to remote regions for efficient water treatment. Graphene was discovered as a single-layer of isolated graphite atoms arranged in 2D hexagonal shape, making it the thinnest and strongest material known to date. Despite its intriguing mechanical, thermal and electrical properties, usage of graphene for different industries has not been investigated in detail. The present study investigated the availability and practical use of graphene inclusions for desalination of salt water to produce fresh water. In the present study, graphene was added to 3.5wt% salt water (similar to sea water) at different percentages. Graphene has a high absorption capability to convert solar energy into heat to enhance the evaporation rate of salt water. The graphene inclusions can also be used to remove bacteria, viruses, fungi, heavy metals and ions, complex organic and inorganic compounds, and other pathogens and pollutants present in various water sources (e.g., surface, ground water, and industrial water).

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