The effect of salinity on the growth, water status, and ion content on Common bean (Phaseolus vulgaris. L. var. El-Djadida)

2018 ◽  
Vol 7 (4) ◽  
pp. 147-156
Author(s):  
Laredj-Zazou Rahma ◽  
Toumi Benali Fawzia ◽  
Bouazza Sofiane

Stress salinity has an important effect on crops physiology. The scope of our study was to evaluate the effect of salt stress tolerance as determined through growth attributes, water status and ion content in (Phaseolus vul-garis. L), the variety of El-Djadida in 6 weeks post stress application. The ex-periment was performed under glasshouse, in controlled conditions, in pots and irrigated with nutrient solution of Hoagland. Plants were irrigated with water containing sodium chloride alone (100 and 200 meq.l-1) combined with sodium chloride (NaCl) and calcium chloride (CaCl2) (100 and 150 meq.l-1). The results obtained showed that the salt application had a depressive effect on the organic growth however, this trend was dependant on the intensity of the stress. The hydric state of the plant varied with the concentration of sub-strate, thus exhibiting the ability to moderate the sensitive plant to adjust gradually to their osmotic pressure even by maintaining high concentrations of K+. The distribution of Na+, K+ and Ca++ in plant organs leaves and roots highlighted that the high level of salinity increased with levels of Na+ which inhibited the absorption of Ca++ and K+ ions.

2007 ◽  
Vol 10 (13) ◽  
pp. 2225-2230 ◽  
Author(s):  
Mustapha Gorai ◽  
Ahmedou M. Vadel ◽  
Mohamed Neffati ◽  
Habib Khemira

1970 ◽  
Vol 64 (1) ◽  
pp. 150-158 ◽  
Author(s):  
S. Pors Nielsen

ABSTRACT Intravenous infusion of isotonic magnesium chloride into young cats with a resultant mean plasma magnesium concentration of 7.7 meq./100 g protein was followed by a significant lowering of the plasma calcium concentration in 90 minutes. The rate of decrease of plasma calcium is consistent with the hypothesis that calcitonin is released by magnesium in high concentrations. There was no decrease in the plasma calcium concentration in cats of the same weight thyroparathyroidectomized 60 min before an identical magnesium chloride infusion or an infusion of isotonic sodium chloride at the same flow rate. The hypercalciuric effect of magnesium could not account for the hypocalcaemic effect of magnesium. Plasma magnesium concentration during magnesium infusion into cats with an intact thyroid-parathyroid gland complex was slightly, but not significantly higher than in acutely thyroparathyroidectomized cats.


1979 ◽  
Vol 39 (1) ◽  
pp. 383-396
Author(s):  
J.R. Nilsson

Lead acetate (0.1–0.2%) forms a precipitate with the organic growth medium. The Tetrahymena cells ingest this lead-containing precipitate and cell growth is resumed after a variable lag period. Ingested lead is observed as electron-dense material in food vacuoles. Soon after exposure, cytoplasmic lead (preserved with certain fixation only) is revealed as electron-dense particles in cilia and in a halo around digestive vacuoles. Later the lead particles pervade the entire cell but after the lag period they are confined to membrane-bound spaces. In dilute growth medium, high concentrations of lead inhibit food-vacuole formation and cell growth. Under these conditions lead is deposited in alveoli of the pellicle and is also found in autophagic vacuoles and other membrane-limited structures. The study has revealed that lead enters Tetrahymena through the membrane of digestive vacuoles and through the cell surface. The change in distribution of lead during the lag period indicates that a mechanism is activated for removal of lead into membrane-bound spaces. The final storage of lead seems to be in lysosomes.


Horticulturae ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 59
Author(s):  
Carlos Agius ◽  
Sabine von Tucher ◽  
Wilfried Rozhon

Hydroponic cultivation of vegetables avoids problems with soil-borne plant pathogens and may allow higher yield. In arid climates and particularly on islands, high concentrations of sodium chloride can be present in the groundwater. For instance, in many sites of Malta, the groundwater contains more than 10 mM sodium chloride. Here we investigated the effects of sodium chloride at levels typically found in Malta on yield, physiology and fruit quality of tomato, the economically most important vegetable. We selected cherry tomatoes since their production is attractive due to their high marketing value. While the yield declined at higher salinity levels tested (17 and 34 mM), the quality increased significantly as indicated by higher total soluble solids and fructose and glucose levels. The type of substrate—coco peat, perlite or Rockwool—had only minor effects. Although the concentration of citric acid and malic acid remained unaffected, the pH dropped by approximately 0.1 unit and the titratable acidity increased slightly. This might be explained by a high uptake of chloride but a lower increase of the sodium content and a reduced potassium level in the fruits, shifting the equilibrium of the organic acids more to their protonated forms. Proline increased significantly, while the level of glutamic acid, which is crucial for the taste, remained unchanged. Our results show that cherry tomatoes can be cultivated in nutrient solutions prepared with salt-containing groundwater, as found in Malta. The yield declined to some extent but the quality of the produced fruits was higher compared to cultivation in salt-free media.


2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Vedran Šupuković ◽  
Zvonko Merkaš ◽  
Zoran Gajić

Operational leverage measures the level of fixed costs in the company’s total expense and has a significant impact on the profitability of a company, especially in activities where large initial investment is necessary, and long acclimatization timeframes and high levels of revenue are needed to reach the profitability threshold. Fixed costs do not grow linearly with revenue growth and thus negatively affect profit with an insufficient level of total revenue. The paper explores the possibilities of using an operational leverage in combination with commercial policy in order to create a profit multiplier. Research has been conducted in companies in the Republic of Croatia that operate in continuity with low levels of profitability, up to 5% of net profit. In the research, the main hypothesis of work is set, by which the operational leverage is defined as a profit multiplier under the conditions of even the smallest organic growth of the enterprise in case it also operates with a high level of fixed costs. The paper begins with the fact that the effect of the operational leverage is of particular importance in certain segments of the economy that are constrained by the impossibility of entering into part of fixed costs and that their increase in profitability depends solely on the level of healthy organic growth. Accordingly, a model is considered in which an operational leverage has the ability to progressively leverage profitability, which in combination with the adequate application of commercial policy measures determines the dynamic character or processes that generate a multiplication effect even in the case of very small revenue growth. In this and such context, we are talking about the significant effect of operational leverage on company’s profitability even when neglected revenue growth affects the level of fixed cost reduction in relation to total revenue, thereby increasing profitability.


2019 ◽  
Vol 31 ◽  
pp. 1-14
Author(s):  
Silviu Bercea ◽  
Ruxandra Năstase-Bucur ◽  
Oana Teodora Moldovan ◽  
Marius Kenesz ◽  
Silviu Constantin

The human impact upon the subterranean microbiomes is not only a peril to the cave environment but might also affect future visitors. We focused on the changes that humans induced on the surfaces they came in direct or indirect contact with inside two intensely visited Romanian show caves, by means of commercially available microbial rapid test kits and molecular identification. Overall culturable bacteria abundance in the caves maintained high levels year-round while Enterobacteriaceae, coliform bacteria and Escherichiacoli levels peaked during the touristic season, reaching levels that could pose a threat to the health of the visitors. Culturable fungi abundance usually peaked in the spring, remained at a high level in the summer and started to slowly decrease towards the winter months. Differences were observed between the direct and indirect exposed surfaces, as the later had lower overall levels of bacteria and fungi, with increased Enterobacteriaceae loads. Most of the taxa identified are known biodeteriorants of subterranean surfaces and were previously associated with human altered caves. A Dothideomycete sp. previously unknown to the cave environments was detected. This was the first study to analyse the dynamics of the microbial communities of delicate subterranean surfaces in show caves through the use of commercially available test kits. We revealed that exposed surfaces in show caves, in direct or indirect contact with tourists, are host to high concentrations of cultivable microbes. The touristic activity was shown to influence the abundance and dynamics of the microbial communities inhabiting surfaces of show caves.


Author(s):  
Jen-Hau Chen ◽  
Tsung-Yu Kuo ◽  
Hwa-Lung Yu ◽  
Charlene Wu ◽  
Su-Ling Yeh ◽  
...  

Background: Previous studies have assessed limited cognitive domains with relatively short exposure to air pollutants, and studies in Asia are limited. Objective: This study aims to explore the association between long-term exposure to air pollutants and cognition in community-dwelling older adults. Methods: This four-year prospective cohort study recruited 605 older adults at baseline (2011–2013) and 360 participants remained at four-year follow-up. Global and domain-specific cognition were assessed biennially. Data on PM2.5 (particulate matter ≤ 2.5 μm diameter, 2005–2015), PM10 (1993–2015), and nitrogen dioxide (NO2, 1993–2015) were obtained from Taiwan Environmental Protection Administration (TEPA). Bayesian Maximum Entropy was utilized to estimate the spatiotemporal distribution of levels of these pollutants. Results: Exposure to high-level PM2.5 (>29.98 μg/m3) was associated with an increased risk of global cognitive impairment (adjusted odds ratio = 4.56; β = −0.60). High-level PMcoarse exposure (>26.50 μg/m3) was associated with poor verbal fluency (β = −0.19). High-level PM10 exposure (>51.20 μg/m3) was associated with poor executive function (β = −0.24). Medium-level NO2 exposure (>28.62 ppb) was associated with better verbal fluency (β = 0.12). Co-exposure to high concentrations of PM2.5, PMcoarse or PM10 and high concentration of NO2 were associated with poor verbal fluency (PM2.5 and NO2: β = −0.17; PMcoarse and NO2: β = −0.23; PM10 and NO2: β = −0.21) and poor executive function (PM10 and NO2: β = −0.16). These associations became more evident in women, apolipoprotein ε4 non-carriers, and those with education > 12 years. Conclusion: Long-term exposure to PM2.5 (higher than TEPA guidelines), PM10 (lower than TEPA guidelines) or co-exposure to PMx and NO2 were associated with poor global, verbal fluency, and executive function over 4 years.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Wiggert J. Altenburg ◽  
N. Amy Yewdall ◽  
Daan F. M. Vervoort ◽  
Marleen H. M. E. van Stevendaal ◽  
Alexander F. Mason ◽  
...  

AbstractThe cell cytosol is crowded with high concentrations of many different biomacromolecules, which is difficult to mimic in bottom-up synthetic cell research and limits the functionality of existing protocellular platforms. There is thus a clear need for a general, biocompatible, and accessible tool to more accurately emulate this environment. Herein, we describe the development of a discrete, membrane-bound coacervate-based protocellular platform that utilizes the well-known binding motif between Ni2+-nitrilotriacetic acid and His-tagged proteins to exercise a high level of control over the loading of biologically relevant macromolecules. This platform can accrete proteins in a controlled, efficient, and benign manner, culminating in the enhancement of an encapsulated two-enzyme cascade and protease-mediated cargo secretion, highlighting the potency of this methodology. This versatile approach for programmed spatial organization of biologically relevant proteins expands the protocellular toolbox, and paves the way for the development of the next generation of complex yet well-regulated synthetic cells.


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