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Ten Solanum tuberosum cultivars and accessions from 11 wild Solanum species were evaluated for their tolerance to salt (200 mM NaCl or 100 mM Na2SO4), drought (35% PEG), cold (-4ºC) and heat (37ºC). Evaluation was based on electrolyte leakage from de-tached leaves of in vitro plantlets. Testing involved a rinsing treatment with three changes of distilled water to remove electrolytes from leaf and petiole surfaces, an exposure period of 24 hours for salt and PEG stress and four hours for temperature stress and a rehydra-tion period of 24 hours in distilled water followed by measurement of electrical conductiv-ity into distilled water to determine the effects of stress. Significant differences were ob-served between Solanum genotypes for all types of stresses. Among the S. tuberosum culti-vars, stress tolerance was great to NaCl and PEG in Alpha and Bintje; to Na2SO4 in Agria and to heat and cold in Norland. Among the wild species, tolerance to all stresses was great in S. demissum, to all stresses except heat in S. acaule and to heat and cold in S. commersonii. The correlations among types of stress tolerance were significant for all stresses except for heat and drought. The level of tolerance in some wild species was sig-nificantly greater compared with the cultivars tested. There appears to be a wide genetic base available to improve the stress tolerance of cultivated potato.

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Aim This investigation aims to study the effect of biochar on gas exchange, water relations and photosynthetic pigments of European yew (Taxus baccata) seedling in different light intensities (LI).
Materials and Methods Two-year potted seedlings of European yew are placed in forest stands with canopies of closed (15% LI), semi-closed (45% LI) and open (75% LI). In late June 2018, biochar was added to potted soils at the levels of zero, 10, 20 and 30 g.kg^-1 and until the end of November, every 3 (or 4) days 100 mL water was given to each pot.
Findings Seedling survival at different levels of treatments was 100%. Regardless of biochar, the highest photosynthesis, stomatal conductance, intercellular CO₂ concentration, relative water content, chlorophyll (chl) contents in closed canopy, and the highest leaf temperature in open canopy was observed. With increasing biochar concentration, chl b and total chl increased (28-86%, respectively) in open canopy and decreased (28 and 28%, respectively) in closed canopy. Neither biochar nor LI affected significantly electrolyte leakage and carotenoid content.
Conclusion Although yew seedlings were able to maintain their vegetative quality and health in different LI, and the measured variables responded differently to light-biochar combination, it may be best to grow yew in shade together with biochar. Since, the effect of biochar becomes more tangible over time, further research in next years can lead to more accurate findings affected by the combined light-biochar treatment.

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Changes in dietary electrolyte balance influence the metabolic fate of protein and many amino acids. Furthermore, acid-base condition is achieved in part by the alteration of dietary amino acids pattern and quantity. Therefore, a trial was conducted in a completely randomized design to evaluate performance, carcass characteristics, plasma electrolyte and uric acid concentrations of 19 and 28-day-old male broilers fed three experimental diets in which CP was decreased in a stepwise manner from 21 to 18%. Ileal digestible quantities of all EAA were almost equal in the diets, and the total amount of each EAA was maintained at or above NRC 1994 requirements. Decreasing dietary CP did not affect performance and appetite but increased fat deposition in the whole body and abdominal cavity, significantly. High crude protein fed chickens generally produced breast, thighs and total carcasses that were lower in fat. Reducing dietary CP increased the concentrations of main plasma electrolytes including ionized forms of the electrolytes (Na+, K+, Cl-) but its influence on Ca++ and HCO3- ions was not significant. On the other hand, plasma uric acid concentration was reduced in parallel with crude protein reduction. Therefore, although reduction of CP to 18% does not impair the performance of broiler chickens, deficiency in uric acid production in low CP diets may lead to blood electrolyte imbalance.

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Reactant gases should be humidified before entering a polymer electrolyte membrane (PEM) fuel cell stack. Humidification of the gases can be performed by a membrane humidifier. In the present study, an analytical model has been proposed to investigate the performance of a water-gas membrane humidifier which is used in the fuel cell systems. At first, a set of nonlinear equations was obtained by applying the mass and energy conservation laws on the gas side of the humidifier. The temperature and the humidity ratio of the outlet gases from the humidifier are the unknowns of these nonlinear equations. The proposed model can evaluate the performance of the humidifier based on the temperature and relative humidity of the outlet gases from the humidifier. The effects of different parameters like: gas flow rate, channel's length and depth, temperature and pressure of the inlet gases on the performance of the humidifier were studied by the developed model. The results show that the channel depth does not have an effect on the temperature and humidity of the humidified outlet gases. In addition, increasing the channel length causes an increase on the dew point of the outlet gases but the relative humidity of the dry inlet gas does not have a noticeable effect on the dew point of the outlet gases. Increasing the temperature of the inlet gases cannot improve the humidifier performance, considerably. The results of the model show that increasing the inlet pressure and using less air flow improve the humidifier performance.

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Using the renewable energy resources has attracted the attention of researchers and automobile companies, because of limited fossil fuel resources, low efficiency of internal combustion engines and their environmental pollutions. By using the fuel cell systems instead of internal combustion engines can be partially overcome these problems. In this regard, the present article examines a PEM fuel cell system for using in an urban vehicle. In the first part of this article, by using the real component of system, the fuel cell system components including stack, membrane humidity of air and hydrogen, air compressor, water pump and pump cooler stack has been modeled in MATLAB Simulink environment. The mentioned model can evaluate the power consumption of system and its peripheral component and also required water, hydrogen and air for system. At the base case and the current density of 0.7A / cm2, 14% of power productions of stack are consumed by auxiliaries units. At this current density, the overall and net system efficiencies are 48.15% and 34.3%. In the second part of this article, the system from the point of view of the first law of thermodynamics has been optimized with objective functions of maximum output power and maximum efficiency. The results indicate that first model search method is best method for optimization, second at the Optimization with the aim of maximum power, pure power and system efficiency are increased 11.9% and 4% respectively and the power consumption by auxiliary unit is reduced 42%.

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Electrolyte type, due to the nature of its constituent ions, affects the reaction rate, the uniformity of the electric field and formation of the external layer on the workpiece surface in the machining area during the electrochemical machining process, as well as it causes to create different dissolution behaviors of the workpiece. Therefore in this study the effect of sodium chloride, sodium nitrate, potassium chloride and hydrochloric acid electrolytes with different currents on the electrochemical machining characteristics of stainless steel 304, including material removal rate, side gap and surface roughness, has been investigated. The results showed that the formation of passive layer during the machining with sodium nitrate electrolyte reduces the material removal rate and side gap compared with sodium chloride and potassium chloride electrolytes. According to the experimental results the surface roughness in the sodium chloride and potassium chloride electrolytes is decreased by increasing the machining current, but increases in the sodium nitrate electrolyte. Also the material removal rate slight increase and side gap increase at sodium chloride, sodium nitrate and potassium chloride when combined with hydrochloric acid. On the other hand, the surface roughness reduces in the combined sodium chloride and potassium chloride electrolytes, but increases in the combined sodium nitrate electrolyte.

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Heat and mass transfer in textiles are usually simulated using models that consider sorption and condensation. But in electrolyte solutions, ions existed in fluid passing the textile can cause a phenomenon called electric double layer. Charges on the textile pores will attract the ions with opposite charge which will affect the fluid flow. To investigate this effect, Poisson-Boltzmann equation is solved beside the other governing equations of the phenomenon. Net electric charge density is computed from this equation and is applied to liquid diffusion coefficient. In this research, the influence of electric double layer is shown and then the factors affecting the strength of this phenomenon have been studied. One side of the textile is thoroughly in contact with liquid and other side is in contact with air. To validate the obtained results, temperature variations in the outer side of the textile are computed and compared with the available experimental works. There is a good agreement between the results. According to the results, applying electric double layer effect in equations cause temperature difference to 20 percent in the outer surface of textile to lack of consideration this. In addition, time for textile full saturation when the electric double layer is considered, increased more than fivefold. The results show that by reducing the viscosity of fluid. The effect of electric double layer on the textile's outer surface temperature has increased. Porosity and zeta potential are other influential factors which according to calculations, increasing each effect can be accelerated electric double layer.

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In this paper, the effect of adding a hydrophobic micro porous layer (MPL) at the cathode side of a PEM fuel cell on the cell performance is investigated. For this purpose, a three dimensional two-phase non-isothermal simulation of cathode side layers of a PEM fuel cell which includes gas channel, gas diffusion layer (GDL), hydrophobic micro porous layer (MPL) and catalyst layer (CL) has been performed. The governing equations of fluid flow in the fuel cell are solved with a multiphase mixture model via developing a code and distribution of velocity, pressure, temperature, species concentration and liquid water saturation at the various layers of the cathode side of fuel cell are obtained. Furthermore, the effect of physical and wetting properties of MPL including thickness, porosity, contact angle and permeability on saturation level and performance of the fuel cell are studied. The results show that by adding an extra micro porous layer between GDL and catalyst layer because of differencing in the wetting properties of the layers, a discontinuity appears in the liquid saturation and species concentration at the contact surface of them. In addition, according to the obtained results, increasing the MPL porosity cause to decreasing liquid water saturation and improving the cell performance. While increasing the MPL thickness decreases the cell performance. In order to validate the results, the performance curves calculated by single and two-phase simulating were compared with experimental results and a good agreement was found between them.

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The aim of this study was to assess the effectiveness of the individual application of nitric oxide or cellophane wrapping, and combination effects of these treatments on reducing chilling injury and quality improvement of pomegranate fruit cv. ‘Shishe-Kab’ during storage. Fruits were dipped in nitric oxide (0 or 300 μM) solution for 2 minutes, followed by cellophane wraps (wrapped or unwrapped) as treatments and then stored at two different storage temperatures (1 or 5°C) for 90 days. Application of 300 μM nitric oxide significantly increased the antioxidant activity, total anthocyanin content, and the a* value of aril color, and also led to the lowest chilling injury and electrolyte leakage in fruit compared with the control. The lowest weight loss, chilling injury, and total soluble solids and the highest total anthocyanin content and the a* value of aril color was observed in cellophane wrapped fruits, compared with unwrapped fruits. The combination of nitric oxide and cellophane wrapping had a greater effect on reducing the electrolyte leakage of fruits as it decreased about 72 and 63% compared to the control in stored fruit for 45 and 90 days, respectively.
 

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Background & Aim: Fluid-electrolyte balance is a dynamic process that is necessary for the continuation of life and homeostasis. Disorders in the bodychr('39')s electrolyte balance and renal dysfunction are related factors in aggravation of symptoms, mortality and length of hospital stay and treatment costs, so we decided To conduct a study by examining the status of electrolyte disorders and its related factors in patients admitted to Shohada Ghaen Educational and Medical Center.
Methods: The present study is a descriptive-analytical study that was performed by census method on all patients admitted to Shohada Ghaen Hospital in 2017. The tools used in this research included a researcher-made checklist that had 11 items that were completed by the researcher. For data analysis, descriptive statistics such as mean, standard deviation and frequency tables and chi-square test and Kruskal-Wallis. Significance level was set at (P <0.05).
Results: 873 patients with a mean age of 22.92 ± 58.42 were studied. The results showed that there was a significant relationship between electrolyte disorders and the level of education, type of disease and disease ward (P <0.05).
Conclusion: Increasing knowledge and awareness has a great effect on the prevention of electrolyte disorders. Also, due to the relationship between electrolyte disorders and the type of disease, special attention should be paid to this issue.