The High Salt Requirement of the Moderate Halophile Chromohalobacter salexigens DSM3043 Can Be Met Not Only by NaCl but by Other Ions

ABSTRACT The growth rate of Chromohalobacter salexigens DSM 3043 can be stimulated in media containing 0.3 M NaCl by a 0.7 M concentration of other salts of Na+, K+, Rb+, or NH4 +, Cl−, Br−, NO3 −, or SO4 2− ions. To our knowledge, growth rate stimulation by a general high ion concentration has not been reported for any organism previously.

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StalGrowth—A Program to Estimate Speleothem Growth Rates and Seasonal Growth Variations

Geosciences ◽

10.3390/geosciences11050187 ◽

2021 ◽

Vol 11 (5) ◽

pp. 187

Author(s):

Rolf Vieten ◽

Francisco Hernandez

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Environmental Parameters ◽

Ion Concentration ◽

Radiometric Dating ◽

Seasonal Growth ◽

Climate Signal ◽

Show Evidence ◽

Cave Monitoring ◽

Calcium Ion Concentration

Speleothems are one of the few archives which allow us to reconstruct the terrestrial paleoclimate and help us to understand the important climate dynamics in inhabited regions of our planet. Their time of growth can be precisely dated by radiometric techniques, but unfortunately seasonal radiometric dating resolution is so far not feasible. Numerous cave environmental monitoring studies show evidence for significant seasonal variations in parameters influencing carbonate deposition (calcium-ion concentration, cave air pCO2, drip rate and temperature). Variations in speleothem deposition rates need to be known in order to correctly decipher the climate signal stored in the speleothem archive. StalGrowth is the first software to quantify growth rates based on cave monitoring results, detect growth seasonality and estimate the seasonal growth bias. It quickly plots the predicted speleothem growth rate together with the influencing cave environmental parameters to identify which parameter(s) cause changes in speleothem growth rate, and it can also identify periods of no growth. This new program has been applied to multiannual cave monitoring studies in Austria, Gibraltar, Puerto Rico and Texas, and it has identified two cases of seasonal varying speleothem growth.

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Gender- and school-level correlates of growth in health-related fitness knowledge among US high-school students

Health Education Journal ◽

10.1177/0017896918785930 ◽

2018 ◽

Vol 77 (8) ◽

pp. 927-938 ◽

Cited By ~ 3

Author(s):

Xihe Zhu ◽

Justin A Haegele

Keyword(s):

High School ◽

Growth Rate ◽

High School Students ◽

Hierarchical Linear Model ◽

School Level ◽

Student Health ◽

School Students ◽

Knowledge Growth ◽

Health Related ◽

Health Related Fitness

Objective: Health-related fitness knowledge holds the potential for physical activity and behavioural changes. The purpose of this retrospective longitudinal study with retrospective data was (a) to examine high-school students’ health-related fitness knowledge growth through the 9th, 10th and 11th grades under one curriculum condition and (b) to examine gender- and school-level correlates of students’ health-related fitness knowledge and its rate of growth. Method: This study used existing data collected by school districts as they implemented the curriculum. Participants were students ( n = 9,883, 49.4% girls) from 40 high schools following the same curriculum. Health-related fitness knowledge performance was assessed annually for 3 years using an online platform. Potential student- and school-level correlates were collected. A three-level hierarchical linear model was used to examine student health-related fitness knowledge growth and its relation to gender- and school-level correlates. Results: The results showed that high-school student health-related fitness knowledge growth was linear during the 3-year period, with an estimated growth rate of 9.14 ± 1.40% per year under the curriculum condition. Girl students had a higher growth rate than boys, holding other factors constant. Other school-level variables were not significant predictors of health-related fitness knowledge. Conclusion: Overall, the curriculum context was conducive to student health-related knowledge growth. The different knowledge growth rate between boys and girls was a possible reason for gender discrepancy at the 11th grade.

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Electrophoretic characteristics of ram and rabbit spermatozoa

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1961.0072 ◽

1961 ◽

Vol 155 (959) ◽

pp. 292-305 ◽

Cited By ~ 16

Keyword(s):

Electric Field ◽

Swimming Speed ◽

Salt Concentration ◽

High Salt ◽

Ion Concentration ◽

Ground Speed ◽

Constant Ph ◽

Electrophoretic Velocity ◽

Low Ionic Strength ◽

Rabbit Spermatozoa

1. The influence of a d. c. electric field on the direction in which ram and rabbit spermatozoa swim has been investigated. The magnitude of the electrophoretic component is so small in the presence of high salt concentrations ( μ = 0.1) that it plays no part in controlling the direction in which the spermatozoa swim. A significant electrophoretic velocity component can, however, be imposed if the spermatozoa are suspended in a diluent (277 mM-fructose) with a low ionic strength ( μ < 0.01). In this condition higher field strengths can be applied without any concomitant rise in temperature, and the ζ-potential increases because the gegen-ion concentration is reduced. 2. In a diluent containing 277 mM-fructose and 10 mM-NaCl two types of spermatozoa are seen when the electric field is applied. Their orientation depends on whether they carry a net negative charge in the region of their heads or their tails. 'Head-anode' spermatozoa swim with unusual rapidity towards the anode but immediately decelerate when the field is switched off. ‘Tail-anode' spermatozoa have a variable ground speed and may, if the field strength is high, be seen swimming tail first towards the anode. They accelerate away from the anode when the field is switched off. 3. The proportions of the two types of spermatozoa vary with salt concentration at constant pH, and with pH at constant salt (10 mM-NaCl) concentration. 4. If the swimming speed of spermatozoa is reduced by cooling, electrophoresis in the presence of high salt concentration ( μ = 0.1) differentiates spermatozoa into two kinds in another way. Both are oriented with their tails pointing towards the anode (tail-anode), but their net ground speed may vary in magnitude and direction according to their inherent swimming speed. Complete immobilization of the spermatozoa resulted in a uniform electrophoretic migration towards the anode, tail first, at all pH’s above 3.5. 5. The implications of these findings are discussed with respect to sperm phenotypes and their possible electrophoretic separation.

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Mapping the Fundamental Niches of Two Freshwater Microalgae,Chlorella vulgaris(Trebouxiophyceae) andPeridinium cinctum(Dinophyceae), in 5-Dimensional Ion Space

International Journal of Ecology ◽

10.1155/2011/738035 ◽

2011 ◽

Vol 2011 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Terence J. Evens ◽

Randall P. Niedz

Keyword(s):

Growth Rate ◽

Experimental Design ◽

Chlorella Vulgaris ◽

Growth Rates ◽

Ion Concentration ◽

Freshwater Microalgae ◽

Batch Cultures ◽

Fundamental Niche ◽

Maximum Cell ◽

Cell Densities

The fundamental niche defined by five ions,NO3 −,PO4 3−, K+, Na+, andCl−, was mapped forChlorella vulgaris(Trebouxiophyceae) andPeridinium cinctum(Dinophyceae) growth rates and maximum cell densities in batch cultures. A five dimensional ion-mixture experimental design was projected across a total ion concentration gradient of 1 to 30 mM to delineate the ion-based, “potential” niche space, defined as the entiren-dimensional hypervolume demarcated by the feasible ranges of the independent factors under consideration. The growth rate-based, fundamental niche volumes overlapped for ca. 94% of the ion mixtures, although the regions of maximal growth rates and cell densities were different for each alga. BothC. vulgarisandP. cinctumexhibited similar positive responses to cations and negative responses to anions. It was determined that total ion concentration for these five ions, from 1 to 30 mM, did not directly affect either growth rate or maximal cell density for either alga, although it did play an interactive role with several ions. This study is the first that we are aware of to attempt the mapping of a multivariate, ion-based, fundamental niche volume. The implications of the experimental design utilized and the potential utility of this type of approach are discussed.

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Biochemical Effects of Aqueous Extract of Persea americana (Mill) on the Myocardium of Left Ventricle of High Salt–Fed Adult Wistar Rats

Journal of Evidence-Based Complementary & Alternative Medicine ◽

10.1177/2156587217733884 ◽

2017 ◽

Vol 22 (4) ◽

pp. 765-769

Author(s):

Ayoola I. Olushola ◽

Komolafe O. Aderibigbe ◽

Saka O. Stephen ◽

Odukoya S. Ayodeji

Keyword(s):

Nitric Oxide ◽

Lactate Dehydrogenase ◽

Wistar Rats ◽

Potassium Ion ◽

Persea Americana ◽

High Salt ◽

Sodium Ion ◽

Ion Concentration ◽

High Salt Diet ◽

Salt Diet

Background. The cardioprotective effects of Persea americana extract was investigated on biochemical activities of high salt–fed adult Wistar rats in this study. Method. Forty healthy Wistar rats of both sexes weighing 120 to 150 g were randomly assigned into 8 groups of 5 rats each (groups A, B, C, D, E, F, G, and H). Rats in groups A, F, G, and H were fed with standard laboratory pellets, while groups B, C, D, and E were fed on the high-salt diet for 4 weeks. Concomitantly, daily administration of 50, 100, and 150 mg/kg of the P americana extract were given orally to groups C and F, D and G, and E and H, respectively, while rats in groups A and B were administered distilled water. Blood samples were taken by cardiac puncture; concentration of sodium ion, potassium ion, nitric oxide, and activity of lactate dehydrogenase were determined. One-way analysis of variance was used to analyze data, followed by Student-Newman-Keuls (SNK) test for multiple comparison. Results. Results revealed that concentration of potassium ion and nitric oxide was significantly lower ( P < .05) in high salt–fed groups. Sodium ion concentration and activity of lactate dehydrogenase were higher in high salt–fed group while P americana prevented biochemical perturbations in other experimental groups. Conclusion. In conclusion, high salt–diet induced biochemical alterations which were significantly protected by oral administration of P americana extract.

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Enhancing growth rate and lipid yield of Chlorella with nuclear irradiation under high salt and CO2 stress

Bioresource Technology ◽

10.1016/j.biortech.2015.12.032 ◽

2016 ◽

Vol 203 ◽

pp. 220-227 ◽

Cited By ~ 38

Author(s):

Jun Cheng ◽

Hongxiang Lu ◽

Yun Huang ◽

Ke Li ◽

Rui Huang ◽

...

Keyword(s):

Growth Rate ◽

High Salt ◽

Lipid Yield

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Effect of sodium chloride on leaf succulence and area of Atriplex hastata L.

Australian Journal of Botany ◽

10.1071/bt9580306 ◽

1958 ◽

Vol 6 (4) ◽

pp. 306 ◽

Cited By ~ 29

Author(s):

RF Black

Keyword(s):

Growth Rate ◽

Sodium Chloride ◽

Epidermal Cell ◽

High Salt ◽

Limiting Factors ◽

Main Emphasis ◽

Palisade Tissue ◽

Moisture Sensitive ◽

Living Leaf ◽

Leaf Succulence

The effect of NaCl in water cultures on morphology and histology are studied with A. hastata, a semisucculent halophyte with a mesomorphic leaf structure. NaCl is shown to extend the ontogeny of the living leaf, and to produce an accelerated rate of leaf thickening, which has its main emphasis in the extended ontogenetic period. The most rapid thickening rate occurred when a high salt concentration (0.6 m) was applied to only part of the root system, so as not to impede a rapid general growth rate in the plant. Maximum leaf areas occurred in 0.1m NaCl cultures, minimum areas in 0.6 m. Epidermal cell areas in a 0. m treatment were double those of the treatment devoid of NaCl and those in the 0.6 m treatment. Numbers of epidermal cells per leaf decreased progressively with increasing concentrations of NaCl. The salt-induced thickening rate is looked upon as a process superimposed on a rather similar light and moisture-sensitive process. Differences in timing between salt effects on leaf area and succulence are explained by differential vacuolation of epidermis and palisade tissue. The high-salt cultures (0.4–0.6 m, which greatly reduced growth, apparently did not reduce turgor pressures necessary for succulence. It is considered that the data required to explain differences noted in epidermal cell size are relationships between their rates of expansion and the rates of maturation of structural limiting factors.

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