The accumulation of 137Cs by brackish water invertebrates and its relation to the regulation of potassium and sodium

1963 ◽  
Vol 43 (2) ◽  
pp. 541-565 ◽  
Author(s):  
G. W. Bryan
Keyword(s):  
New Media ◽  
Brackish Water ◽  
Sea Water ◽  
Indirect Evidence ◽  
The Body ◽  
Limiting Factor ◽  
Wide Range ◽  
Concentration Factors ◽  
The Relationship ◽  
Potamopyrgus Jenkinsi

The relationship between the ability of brackish water invertebrates to regulate Na and K and the extent to which the radioactive fission product 137Cs can be accumulated has been studied.The brackish water isopod Sphaeroma hookeri and the gastropod Potamopyrgus jenkinsi have been acclimatised to a wide range of sea-water dilutions. Unfed Sphaeroma can survive in sea-water concentrations of 100–2·5%, while Potamopyrgus can live fairly indefinitely in concentrations of 50–0·1%. Measurements of Na and K in the whole animals of both species and in the blood of Sphaeroma have been made. Salt movements are quite rapid and acclimatization to new media is achieved by both species in less than 10 h. Concentration factors for inactive K in particular increase to high values in the more dilute media.Uptake of the isotopes 42K and 137Cs from solution has been examined in both species over a range of sea-water concentrations. All of the body K is exchangeable with 42K and in Sphaeroma exchange of 42K between the blood and tissues is so rapid that the body surface appears to be the limiting factor in the uptake of the isotope. Both species exchange 42K more rapidly in the higher concentrations of sea water and one reason for this may be the existence of an exchange diffusion component of exchange which increases as the salinity of the medium is raised. Indirect evidence suggests that the excretion of 42K in urine is probably not an important factor in exchange.

Potassium metabolism and the accumulation of 137Caesium by decapod Crustacea

1962 ◽  
Vol 42 (2) ◽  
pp. 199-241 ◽  
Author(s):  
G. W. Bryan ◽  
Eileen Ward
Keyword(s):  
Body Surface ◽  
Soft Tissues ◽  
Sea Water ◽  
The Body ◽  
Limiting Factor ◽  
Freshwater Crayfish ◽  
Marine Animals ◽  
Decapod Crustacea ◽  
Concentration Factors ◽  
Potassium Metabolism

SUMMARYThe accumulation of 137Cs from sea water has been examined in relation to potassium metabolism in the lobster Homarus vulgaris and in the prawn Palaemon serratus. In unfed animals 137Cs is taken up and lost far more slowly than 42K. Although all the inactive K in the animals can be exchanged with 42K, higher whole-animal concentration factors are reached for 137Cs (about eight for lobsters and twenty-five for prawns). This is because both species have higher plasma/medium ratios for 137Cs than K at equilibrium despite the selective excretion of 137Cs. Also, except for the hepatopancreas in lobsters and fed prawns, all soft tissues can probably attain higher tissue/plasma ratios for 137Cs than inactive K.Uptake of both isotopes has also been studied in the freshwater crayfish Austropotamobius pallipes pallipes. In crayfish in o-i % sea water 137Cs is not concentrated to the same extent as K by whole animals (50-200 for 137Cs against about 4500 for K). Although the situation between plasma and tissues resembles that in the marine animals, 137Cs cannot be accumulated in the plasma to the same degree as K. Crayfish selectively excrete 137Cs in the urine relative to K at a lower concentration than in the plasma.In the accumulation of 137Cs by all species, muscle is the principal limiting factor in uptake and loss, but with 42K the body surface becomes more limiting.Experiments on the absorption of 137Cs from food in prawns and freshwater crayfish have been carried out. In prawns in a constant environment, feeding is probably less important than uptake over the body surface while in crayfish feeding is probably much more important.

Sodium Influx and Loss in Freshwater and Brackish-Water Populations of the Amphipod Gammarus Duebeni Lilljeborg

1971 ◽  
Vol 54 (1) ◽  
pp. 255-268
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Body Surface ◽  
Brackish Water ◽  
Sea Water ◽  
Sodium Concentration ◽  
The Body ◽  
Experimental Population ◽  
Sodium Ions ◽  
Sodium Influx ◽  
Wide Range ◽  
Freshwater Habitats

1. Sodium influx was examined in Gammarus duebeni from freshwater habitats on the Kintyre and Stranraer peninsulas in western Britain, and from a brackish-water habitat in Ireland. The affinity for sodium ions in the uptake mechanism at the body surface was similar in animals from the three localities. 2. Compared with the parent population from Kintyre, an experimental population established for 2 years in water with a lower sodium concentration showed an increased affinity for sodium. 3. Sodium losses in the urine of animals from the above localities were negligible at external salinities below about 2% sea water. In contrast, urinary sodium losses in animals from a brackish-water population in Britain were higher at salinities ranging from 40% sea water to well below 2% sea water. 4. The affinity for sodium ions in uptake mechanisms at the body surface and in the antennary glands of G. duebeni from a wide range of habitats shows a market correlation with the sodium concentration of the habitat. The permeability of the body surface to outward movement of sodium is similar in G. duebeni from brackishwater and freshwater habitats. 5. It is suggested that most of the observed physiological differences between populations of G. duebeni are phenotypic in origin. The status of the freshwater ‘race’ in Ireland is briefly discussed.

scholarly journals The accumulation of radioactive caesium in crabs

1961 ◽  
Vol 41 (3) ◽  
pp. 551-575 ◽  
Author(s):  
G. W. Bryan
Keyword(s):  
Body Surface ◽  
Natural Environment ◽  
Sea Water ◽  
Carcinus Maenas ◽  
The Body ◽  
Limiting Factor ◽  
A Value ◽  
Cancer Pagurus ◽  
The Relationship ◽  
Accuracy Rates

SUMMARYThe accumulation of 134Cs and 42K from artificial sea water has been followed in crabs of the following species, viz. Carcinus maenas, Portunus puber, P. depurator, Polybius henslowi, Cancer pagurus and Corystes. cassivelaunm. In all cases 134Cs is taken up far more slowly than 42K but at equilibrium a higher concentration factor is attained by 134Cs. In Carcinus a value of about 8 is found for 134Cs and about 4 for 42K. Uptake of 134Cs in Carcinus is not affected by feeding on inactive food over a period of 1000 h. The relationship between the rates of uptake of the two isotopes is not the same in the different species and it is concluded that it would not be possible to predict with any accuracy rates of uptake for 134Cs in other species of crabs from the results of short 42K experiments.Uptake of 134Cs was followed in the blood and tissues of Carcinus and Cancer, and muscle is the principal limiting factor in the attainment of equilibrium by whole animals. Uptake of 42K by tissues has also been followed and in all species nearly all the inactive K appears to be readily exchangeable. At equilibrium in all species plasma/sea water and tissue/plasma 134Cs ratios nearly always exceed those for inactive K. The tissue/plasma 134Cs ratios in Carcinus are about twice those for K and the significance of this has been discussed.Loss of both isotopes in whole Carcinus is a slower process than uptake.Isotope accumulation takes place mainly across the body surface in unfed animals, but uptake of 134Cs from food is very rapid and complete and would considerably enhance the attainment of equilibrium in a natural environment.Selective excretion of 134Cs relative to K has been found in Carcinus, Cancer and Portunus puber.

scholarly journals Hyaluronan and the Fascial Frontier

2021 ◽  
Vol 22 (13) ◽  
pp. 6845
Author(s):  
Rebecca L. Pratt
Keyword(s):  
Nerve Fibers ◽  
The Body ◽  
Water Volume ◽  
Cell Behavior ◽  
Connective Tissues ◽  
Wide Range ◽  
The World ◽  
Extracellular Microenvironment ◽  
The Impact ◽  
The Relationship

The buzz about hyaluronan (HA) is real. Whether found in face cream to increase water volume loss and viscoelasticity or injected into the knee to restore the properties of synovial fluid, the impact of HA can be recognized in many disciplines from dermatology to orthopedics. HA is the most abundant polysaccharide of the extracellular matrix of connective tissues. HA can impact cell behavior in specific ways by binding cellular HA receptors, which can influence signals that facilitate cell survival, proliferation, adhesion, as well as migration. Characteristics of HA, such as its abundance in a variety of tissues and its responsiveness to chemical, mechanical and hormonal modifications, has made HA an attractive molecule for a wide range of applications. Despite being discovered over 80 years ago, its properties within the world of fascia have only recently received attention. Our fascial system penetrates and envelopes all organs, muscles, bones and nerve fibers, providing the body with a functional structure and an environment that enables all bodily systems to operate in an integrated manner. Recognized interactions between cells and their HA-rich extracellular microenvironment support the importance of studying the relationship between HA and the body’s fascial system. From fasciacytes to chronic pain, this review aims to highlight the connections between HA and fascial health.

Zinc Regulation in the Lobster Homarus Gammarus: Importance of Different Pathways of Absorption and Excretion

1986 ◽  
Vol 66 (1) ◽  
pp. 175-199 ◽  
Author(s):  
G. W. Bryan ◽  
L. G. Hummerstone ◽  
Eileen Ward
Keyword(s):  
Sea Water ◽  
Carcinus Maenas ◽  
The Body ◽  
Shore Crab ◽  
Freshwater Crayfish ◽  
Uptake Mechanism ◽  
Major Pathway ◽  
Homarus Gammarus ◽  
Wide Range ◽  
Body Concentration

Zinc is one of the most important of the essential trace metals and more than 90 zinc-containing enymes and proteins have been discovered: furthermore, zinc increases the activity of many other enzymes (Vallee, 1978). It is not surprising, therefore, that in some groups of animals the body concentration is regulated against fluctuations in intake. Decapod crustaceans comprise one such group, although the ways in which regulation is achieved vary from species to species. In the freshwater crayfish, Austropotamobius pallipes, excretion in the faeces is a major pathway for removing zinc (Bryan, 1967a) whereas in the shore crab Carcinus maenas losses over the body surface also assume considerable importance (Bryan, 1966). On the other hand, preliminary work on the lobster Homarus gammarus (formerly H. vulgaris) suggests that in this species urinary excretion plays a major role in regulation (Bryan, 1964). The present work continues the study of zinc regulation in lobsters and its main aims are: (1) to measure rates of absorption from sea water over a wide range of concentrations and study the uptake mechanism; (2) to examine absorption from the stomach under different conditions; (3) to determine the relative importance of different pathways for the removal of zinc in response to various levels of intake.

scholarly journals Survey of compliance with the cigarettes and other tobacco products act, 2003 at schools in Mangalore, Dakshina Kannada district, Karnataka

2019 ◽  
Vol 6 (8) ◽  
pp. 3289 ◽  
Author(s):  
Jennifer Mathias ◽  
Pratap Kumar Jena ◽  
Sanjeev Kumar Shah ◽  
Jay Prakash Sah ◽  
Koshish Raj Gautam ◽  
...  
Keyword(s):  
Public Health ◽  
Indirect Evidence ◽  
The Body ◽  
Smoking Ban ◽  
Cross Sectional Survey ◽  
Government Schools ◽  
Cross Sectional ◽  
Public Places ◽  
Tobacco Products ◽  
Wide Range

Background: Tobacco use is a major problem of public health significance as the tobacco smoking causes a wide range of diseases and adverse health impacts that affect nearly every organ of the body. The COTPA, 2003 i.e., the Indian smoke-free legislation “Prohibition of smoking in Public places” which forbids smoking in public places, including educational institutions. The main objective of this study is to assess the compliance of Section 4 and Section 6(b) of cigarettes and other tobacco products act (COTPA), 2003 in schools, to observe compliance of smoking ban at public places, to observe compliance of display of signboards at prominent places, to observe for direct and indirect evidence of smoking and other tobacco products used in school buildings and premises, to study the availability of tobacco products within 100 yards of school premises.Methods: A cross sectional survey in 100 schools in Dakshina Kannada district using compliance guide developed by partners of Bloomberg School of Public health to reduce tobacco use.Results: In 100 schools, 55 were rural area and 45 from urban area, further division shows government/semi-government schools were 44 and Private schools were 56. Section 4 for the presence of signboard, there is an association between the Management wise schools and presence of signboards (p=0.001), for section 6(b) of COTPA, there is an association between this Section and type of management (p=0.004).Conclusions: The schools depending upon the location show varied compliance towards the law. The Section 6(b) shows better compliance than Section 4.This study will help to address the implementation issues of COTPA. 

Internet i nastava književnosti: digitalni modernizam

2021 ◽  
Author(s):  
Mladen Stanić ◽  
Keyword(s):  
New Media ◽  
The Internet ◽  
Change Communication ◽  
Teaching Aids ◽  
Wide Range ◽  
Methodological Principles ◽  
Continuous Work ◽  
Teacher's Knowledge ◽  
The Relationship

The wide range of questions that this topic raises lead us to think about the training of teachers, their continuous work and improvement. Following this paragraph, we conclude that a textbook/manual, which would deal with the relationship between the Internet and teaching, or the continuous organization of seminars and trainings, is a necessity for literature teachers. In addition to the teacher's knowledge of the coexistence of literature and new media, it is necessary to pay special attention to the critical attitude of students towards Internet content and to point out the purposeful use of newspapers in the teaching process. The role of teachers in modern timesis not favorable because things related to their profession are rapidly developing: new genres appear, tendencies in study and creation change, communication media are continuously changing, and on the other hand teaching it self must undergo changes and transformations. Nevertheless, proven methodological principles always exist, at least as the essence of teaching, regardless of which teaching aids were used and in what way in class. The Internet content and the opportunities it provides have proven to be stimulating and close to the students, so the teacher can use them, with the awareness that the teaching aid must not overshadow the content that is being processed.

Breathing Movements in Entobdella Soleae (Trematoda, Monogenea) from the Skin of the Common Sole

1962 ◽  
Vol 42 (1) ◽  
pp. 93-104 ◽  
Author(s):  
G. C. Kearn
Keyword(s):  
Oxygen Content ◽  
Sea Water ◽  
The Body ◽  
Scyliorhinus Canicula ◽  
Solea Solea ◽  
Flat Fish ◽  
The Common ◽  
The Relationship ◽  
Common Sole

An undulating movement of the body was observed in Entobdella soleae, a monogenean found on the blind surface of a mud-dwelling flat-fish, Solea solea, at Plymouth. The movement is described and shown to have a breathing function, the rate of undulation increasing with decreasing oxygen content of the ambient sea water and vice versa.The relationship between the movement and micro-habitat is discussed and the phenomenon is compared with breathing movements in other muddwelling animals.A similar movement was noted in three other skin-parasitic monogeneans: Acanthocotyle sp. from Raia clavata, Pseudocotyle squatinae from Squatina squatina and Leptocotyle minor from Scyliorhinus canicula.

Mimi Nichter, Fat talk: What girls and their parents say about dieting. Cambridge, MA: Harvard University Press, 2000. Pp. xi, 263. Hb $22.95.

2002 ◽  
Vol 31 (5) ◽  
pp. 811-815
Author(s):  
Mary Bucholtz
Keyword(s):  
Human Body ◽  
Harvard University ◽  
The Body ◽  
Fat Talk ◽  
Teenage Girls ◽  
Wide Range ◽  
Medical Anthropologist ◽  
The Relationship ◽  
Equal Interest

The relationship between language and the body has become an increasingly prominent area of research within linguistics and related disciplines. Some investigators of this question have examined how facts about the human body are encoded in linguistic structure, while others have explored the use of the body as a communicative resource in interaction. Surprisingly little, however, has been written about the role of language in constructing the body as a social object. In Fat talk, Mimi Nichter, a medical anthropologist, addresses this issue by examining the discourse of dieting among American teenage girls. Although language itself is not the center of the analysis, Nichter draws on a wide range of sociolinguistic research to investigate how the body is constructed through talk – a question that will be of equal interest to scholars of language, culture, and society.

scholarly journals Thermal Tolerance in Anuran Embryos with Different Reproductive Modes: Relationship to Altitude

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Manuel Hernando Bernal ◽  
John D. Lynch
Keyword(s):  
Significant Relationship ◽  
Thermal Tolerance ◽  
Altitudinal Gradient ◽  
Environmental Temperature ◽  
Limiting Factor ◽  
Altitudinal Distribution ◽  
Reproductive Modes ◽  
Wide Range ◽  
The Relationship ◽  
Study Species

Anurans are ectothermic animals very sensitive to temperature, mainly during the embryonic stage. In addition, environmental temperature decreases with altitude, and the amphibian fauna changes. Therefore, we studied the relationship between the embryonic thermal tolerances of twelve species of anurans and the temperatures of their microhabitat along an altitudinal gradient from 430 m to 2600 m. We hypothesized that there is a strong thermal adjustment of embryos to their microhabitat and, consequently, that temperature could be a limiting factor of altitudinal distribution of the anurans. We also compared the embryonic thermal tolerances according to six postulated reproductive modes of the study species. We found a significant relationship between the maximum and minimum thermal tolerances of the anuran embryos and the maximum and minimum temperatures of their microhabitat and altitudinal distribution. We also found a wide range of embryonic thermal tolerances for aquatic breeding species and a narrower range for terrestrial breeding species. Particularly, embryos of direct development species were the most sensitive to temperature. These results show the strong thermal adjustment of anuran embryos to their microhabitat and elevation and do not reject the hypothesis that temperature can be a limiting factor of their altitudinal distribution.

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