In hydroponic cultures, the effects of nitrogen form and pH of nutrient solution on the chemical composition of plants are important. In order to study their effects on the uptake and concentrations of K, Ca, Mg and Na in root and shoot of spinach plant, a factorial experiment was conducted with two factors including nutrient solution pH at three levels (4.5, 6.5 and 8) and nitrate to ammonium ratio in nutrient solution at five levels (100:0, 75:25, 50:50, 25:75 and 0:100). The experiment was carried out in a completely randomized design with four replications in perlite culture under greenhouse conditions. Three seedlings of spinach plant (Spinacia oleracea L. Sirius cultivar) were cultivated per pot and with 15 different nutrient solutions were nourished. The concentrations of nitrogen and other nutrients in all nutrient solutions were identical. The plants were harvested after seven weeks and spinach root and shoot concentrations of K, Ca, Mg and Na were measured by wet digestion method. Results showed that the effects of nutrient solution pH on the root and shoot concentrations of K, root concentration of Ca, Ca uptake, shoot concentration of Mg were significant, but on the root and shoot concentrations of Na, Na uptake, root concentration of Mg, and Mg uptake were not. By increasing the nutrient solution pH from 4.5 to 8, K and Ca uptake by plant, and root concentration of K significantly decreased, while shoot concentrations of K and Mg, and root concentration of Ca significantly increased. The main effect of nitrate to ammonium ratio in nutrient solution, and the interactive effects of pH and the ratio of nitrate to ammonium on the root and shoot concentrations of K, Ca, Mg and Na, and their uptake by plant beca,e significant. In general, by decreasing the nitrate to ammonium ratio in nutrient solution, the root and shoot concentrations of K, Ca, Mg and Na, and their uptake by spinach plant became significantly decreased. Also, the effect of nitrate to ammonium ratio of nutrient solution on the root and shoot concentrations of K, Ca, Mg and Na, and their uptake by spinach plant was dependent on the nutrient solution pH and vice versa. The average shoot concentrations of K, Ca, Mg and Na were higher than those in root. There were significant correlations between the shoot and root concentrations of these elements, and also between the elements concentrations in the shoot and their uptake by spinach plant.

To study the effects of potassium (K) and zinc (Zn) with cadmium (Cd) in roots، stem، leaves and fruits of tomato plants، a greenhouse experiment was conducted as factorial based on complete random blocks design. The first factor was Zn at three levels (88. 8، 177. 6 and 355. 2 μg/L) and the second factor was K at three levels (255، 510 and 1020 mg/L). In this experiment، the basic nutrition solution (Hoagland) contained 20 μM Cd in all the treatments. At the second harvest period، the concentration of Cd، K and Zn was measured in different organs of the plants including roots، stem، leaves and fruits. Results indicated that increasing Zn concentration in nutrition solution had no significant effect on concentration of Cd and K in roots; but، it increased Zn concentration in roots. In stem، application of Zn increased concentration of Cd and Zn; but had no effect on K concentration. In leaves، concentration of K and Cd was increased; but no effect was observed on Zn concentration. In fruits، the concentration of Zn، K and Cd was not affected by increasing Zn concentration in nutrition solution. Increasing K concentration in nutrition solution had no significant effect on concentration of Cd، Zn and K in roots. In stem، only the concentration of Zn was increased. But in leaves، Cd reduced and K increased concentration of K. In fruits، it caused an increase in concentration of Zn. Interaction of K and Zn was significant on concentration of K in roots and Zn in fruits. In general، under the conditions of the present research، in tomato plant، Zn and Cd have synergistic effect and K and Cd have antagonistic effect.

AFB1 is a highly carcinogenic secondary metabolite of some species of Aspergillus. Recently, use of microorganisms has been increased to reduce the absorption of mycotoxins in gastrointestinal tract. So, in this study the effect of the three yeasts Saccharomyces cerevisiae, Pichia fermentans, and Rhodotorula mucilaginosa on reduction of AFB1 in a simulated model of human stomach was investigated.

At first, A. flavus was isolated and then were purified. Then, AFB1 was produced in PDB media and presence of AFB1 was determined by blue fluorescence radiation under UV light. Toxin was extracted using the method of solvation in chloroform and injected into HPLC and the final concentration was 49 ng/ml. The simulated stomach was contaminated with 0.1 ml samples of AFB1 of three concentrations: 0.25 ng/ml and 0.50 ng/ml from standard AFB1 and also 49 ng/ml from the A. flavus under study. Then the yeasts were added and the mixture was incubated. After sampling at 0 and 120 minutes, the samples were centrifuged. The supernatants were separated to determine the concentration of residual toxin by direct competitive ELISA method. The experiment was conducted in a completely randomized design with a factorial experiment. The three factors included yeast (four levels: three yeasts and non-yeast treatments), concentration (four levels: 0, 0.25, 0.50 and 0.49 ng/ml) and time (two levels: 0 and 120 min). The whole experiment was carried out 3 times.

The results showed that all three yeasts had the ability to reduce the toxin in the stomach compared to the control treatment (without yeast), but the effect of R.mucilaginosa was more significant than the other two. The lowest toxin concentration in supernatant was observed at 0.25 ng/ml. Over time, toxin concentration in supernatant decreased. The interaction of yeasts and toxin concentration showed that in comparison with the control, at each three concentrations, all three yeasts could reduce toxin concentration. The minimum toxin concentration in supernatant was obtained at 0.25 ng/ml in the presence of R.mucilaginosa. The results of interaction of yeast×time showed that after both 0 and 120 minutes, all three yeasts were able to reduce the toxin and the minimum toxin concentration was observed after 120 minutes for R.mucilaginosa. The results of interaction of time and toxin concentration in the model showed that at 0.25 ng/ml toxin concentration was at the lowest level after 120 minutes. The results of interaction of yeast×time×toxin concentration showed that the lowest toxin concentration was related to R.mucilaginosa after 120 minutes at 0.25 ng/ml. To conclude, the results of this study showed that all three yeasts had the ability to reduce AFB1 in the simulated model of human stomach, but R.mucilaginosa can be introduced as the most efficient isolate in biocontrol of AFB1.

Backgrounds and Due to copper and zinc elements toxicity, a greatly attention to removal of those in order to reduce environmental pollution exist. This experiment was conducted to investigate the study of the effect of gravity single layer rapid sand filter on heavy metals (zinc and copper) removal efficiency in aquatic condition in different phosphate concentration. this study applied a gravity single layer rapid sand filter with silica sand media. Experiments conducted for all of the states of Cooper and Zinc concentration in 25, 75, 125 and 175 ppm at different phosphate concentration present by varied discharge. Each state of Solutions pumped on top of the bed and discharge adjusted. Samples taken fromeffluent then acidified immediately with nitric acid. Metals concentration perused by atomic emission spectrometer with ICP source. Collected data analyzed by SPSS software. Founds from this study shown that maximum removal efficiency for copper and zinc was 98.89%and 78.60%respectively effect of discharge,metal concentration and phosphate concentration factors in removal efficiency of zinc and cooper, discharge and phosphate concentration bilateral effect on cooper removal efficiency, phosphate concentration andmetal concentration bilateral on zinc removal efficiency, are significant in 1%. In addition, phosphate concentration and discharge bilateral effect, metal concentration and discharge bilateral effect are significant on zinc removal efficiency in 5%. Finally, bilateral effects of discharge and metal concentration also metal concentration and phosphate concentration have not significant effect on cooper removal efficiency. Gravity single layer of rapid sandy filter with silica sand media in order to cooper removal in low concentration can be used successfully. This method in high concentration of cooper and also different concentration of zinc had not successful result; but in this condition, may be use of a series of filter with more depth

Solid waste management is one of the biggest challenges faced by the whole world. Increase in the world population which itself leads to the increase in solid waste production has made this problem more and more complex(Singh, et al., 2011). Vermicomposting technology using earthworms for recycling organic wastes has been recognized as an eco-friendly and suitable approach for recycling and managing biological wastes (Padmavathiamma, et al., 2008). but the presence of heavy metals in the vermicompost and the danger of the entry of these metals into the food chain is a genuine threat as far as the living beings are concerned )Azizi, et al. 2013.( Heavy metals such as nickel, cadmium, copper, zinc, manganese, chromium, and lead in a limited amount are required by the plants for a normal growth on the other hand high concentrations of these elements have devastating effects on plant growth)Nayak and Kalamdhad, 2013(. One of the ways for the removal of these elements from the contaminated soil is using tissues of organisms such as plants or invertebrates such as earthworms (Edwards and Arancon, 2004). Due to the accumulation of heavy metals in the intestines of earthworms or due to deformation of metal complexes in the process, these heavy metals change from an accessible to an inaccessible form and the danger of these metals in the agricultural wastes is neutralized (Song, et al., 2014). In this study, soft peel of pistachios have been used for vermicomposting. According to the report submitted by Food and Agriculture Organization, Iran is the world’s largest producer of pistachios. As has been witnessed in the last few years, the total by-products obtained from pistachio cultivation have increased by a rate of 310,000 tons which in itself has changed into an environmental problem(Ghasemi, et al., 2012). As no practical solution is available for this issue, in this study we have tried to make an optimal use of soft peel of pistachios for vermicomposting thus changing it into a useful material and we have also studied the change in heavy metal concentration in vermicomposting of these wastes.
Pistachio waste was collected at the time of pistachio harvest. So as to remove any present phenolic compounds, the waste was mixed with coal powder and then was subjected to pre-composting. Municipal sludge and spent mushroom compost (SMC) were used in order to adjust the C/N ratio. In the next step, 2.5 kilos of the dry weight of the main raw material which comprised of different percentages of soft peel of pistachios, municipal activated sludge and SMC were filled in 12 treatments were analyzed and studied for a period of 70 days. Composition of various treatments shows in table 1.
Table 1. Composition of various treatments for the vermicomposting experiment
Soft peel of pistachios (%) Municipal activated sludge (%) SMC (%) Treatments
100 0 0 A
0 100 0 B
0 0 100 C
40 30 30 D
60 20 20 E
80 10 10 F
40 0 60 G
40 60 0 H
60 0 40 I
60 40 0 J
80 0 20 K
80 20 0 L
Analysis of heavy metals:At the end of the process, one gram of dry and powdered vermicompost was gathered from all beds and was reduced to ashes in a furnace at a temperature of 550 C. 10 ml 2 N HCL was added to the sample, after the absorption of the acid, the quantity of the acid was increased to 50 ml. Atomic absorption spectrometer was used to calculate the amount of heavy metals such as copper, cadmium, zinc, nickel and lead etc. (Salimi, et al., 2016)
Statistical Analysis:Statistical Analysis of the data collected was performed using the software “Minitab version 17” and the average data analysis was done using one-way ANOVA and the Fisher’s method.
Discussion and In this study, a significant reduction was observed in the final treatments as far as Nickel is concerned. The maximum proportion of nickel during the final phase of the process was observed to be 0.021 ppm which is related to the treatment B and in the final phase rest of the treatments lacked nickel in them. This study illustrates the fact that the reduction of nickel in the final treatments was because of the earthworm and micro organism activity present in the vermicompost heap which had led to the decomposition of the organic matter. During the saturation process of organic matter, nickel gets absorbed and accumulates inside the bodies of earthworms and other microorganisms. Also it is seen that due to rinsing of the beds with latex an amount of heavy metals get removed through the poles of the bed thus reducing the overall heavy metal concentration. Singh reports that the concentration of heavy metals in the vermicompost decreases with the increase in time of the decomposition process (Singh, et al., 2011). In a study about the comparison of heavy metal concentration in composting and vermicomposting of organic waste, it was reported that the risk of heavy metals accumulation in the body of the earthworms is reduced in the case of vermicompost that in the case of compost (Mohee and Soobhany, 2014). In this study, at the end of the process, the concentration of copper was observed to increase in all the treatments. Highest concentration of copper was found out to be 2.36 ppm in treatment H and the lowest was about 0.377 ppm in treatment C. The concentration of heavy metals in the vermicompost is related to the concentration these metals in the raw materials present in the bed. The increase in the concentration of copper in the vermicompost is due decrease in volume and mineralization of the organic matter by the earthworms. As per the studies of Nayak and Kalamdhad, the increase in heavy metal concentration can be a result of loss of initial weight due to the decomposition of organic matter and emission of CO2 gas during vermicomposting. As per the studies of Yadav and Garg, contents of metals like iron, copper, lead and zinc in vermicomposting of mixed raw waste was higher than the initial level(Yadav and Garg, 2013). The concentration of cadmium, zinc and lead decreased in some treatments and increased in some others at the end of the process. Maximum concentration of cadmium at the end of the process was observed to be in the treatment “L” and was about 0.024 ppm whereas the minimum concentration of cadmium was 0 ppm in treatments “A”,”E” and “H”. The maximum concentrations of lead at the end of the process were about 0.67 ppm in treatment “B” and 0.65 ppm in treatment “H”. No concentration of lead was found in treatments “A”, “C”,”E”,”F”,”I”,”K” and “L”. The concentration of zinc was also observed to be different in different treatments. The maximum concentration of zinc at the end of vermicomposting was found out to be 14 ppm in treatment “B” and varied drastically from other treatments. The minimum concentration of zinc was observed in treatment “A” and was about 1.26 ppm. The concentration of heavy metals in the first bed, decomposition of organic matter, rate of adsorption and microbial activity directly affect the concentration of heavy metals in the final bed.
In this research, reduction of heavy metal concentration due to leachate leakage, absorption of the metals in the substrate material by earthworms and accumulation of these metals in their tissues has been reported. On the other hand it quite possible to say that during vermicomposting, heavy metal concentration increases due to volume and weight reduction of the materials in the bed due to organic decomposition. Finally, it was found that the concentrations of these metals are within the limits of the national standards of Iran and the use of these fertilizers in agriculture does not have any harmful effect.

The purpose of this study was to compare the performance of Fe2+ activated persulfate and electro-persulfate process in Acid Blue 25 removal from aqueous solution. For this reason, the effects of different parameters including pH, dye, sodium persulfate and ferrous sulfate concentrations were investigated. The removal efficiency of 92% at the time of 60 min was obtained at pH= 3, dye concentration= 50 mg/L, sodium persulfate concentration= 500 mg/L and Fe (II) sulfate concentration= 100 mg/L for Fe2+ activated persulfate system and the removal efficiency of 95% at pH= 5, dye concentration = 200 mg/L, sodium persulfate concentration = 500 mg/L and ferrous sulfate concentration = 100 mg/L for electro-persulfate system by means of graphite materials as the neutral electrodes. COD removal efficiency in Fe2+ activated persulfate and electro-persulfate in the mentioned conditions were 90% and 89% in 180 minutes, respectively. Moreover, the result of process kinetics showed that using electrochemical process improved the reaction velocity from 0.0016 to 0.0487 mg/L/min. The comparison between these two-process showed that using electrochemical process improved dye removal efficiency by 4 times.

The effects of waterlogging, sewage sludge and manure on the Fe, Mn, Zn, Cu, Pb and Cd uptake and concentrations in roots and shoots of sunflower (Helianthus annuus L.) were investigated in greenhouse conditions. A factorial experiment based on a completely randomized design with three replications including duration of waterlogging at five levels (0, 2, 4, 8, 22 days) and source and amount of organic fertilizer at five levels (0, 15 and 30 grams of both manure and sewage sludge per kg of soil) was conducted. The results showed that by increasing the duration of waterlogging, the Mn uptake and concentration in shoots and Mn concentration in roots increased but Mn uptake in roots did not change significantly. The uptake and concentration of Fe in shoots and Cd concentration in shoots and roots initially increased and then decreased after soil waterlogging, while Zn and Cu concentration of roots increased after an initial decrease. The effect of soil waterlogging on the Pb, Cu and Zn concentrations in shoots was not significant. By application of sewage sludge and manure the uptake and concentration of Fe, Mn, and Zn in shoots and Cu uptake in shoots increased but the uptake and concentration of Pb in shoots increased only by application of sewage sludge. The effect of source and amount of organic fertilizer on the Cd uptake and concentration in shoots, Cd concentration in roots and Cu concentration in shoots was not significant. By application of sewage sludge the root concentration of Fe, Mn, Cu and Zn increased but root concentration of Cd and Pb did not change significantly. The maximum uptake of heavy metals in shoots was obtained by application of 30 g sewage sludge/kg of soil. The effect of soil waterlogging on the heavy metals uptake and concentrations in the roots and shoots was dependent on the source and amount of organic fertilizer. Sunflower plant accumulated Fe, Mn, Zn, Cu, and Pb in roots while the Cd concentration in roots did not differ with shoots significantly.

Since agriculture is both the source and sink of greenhouse gases, and plants show different responses to the elevated CO2 concentration, an experiment was conducted in 2006 at the research greenhouse of the faculty of agriculture of Ferdowsi University of Mashhad. The purpose of the experiment was to examine the effects of elevated CO2 on the competition ability between various crops and weeds in factorial arrangement within a completely randomized design with three replications. The factors included ambient (360ppm) CO2 and elevated (700 ppm) CO2 concentrations and various combinations of the plantation of crops (millet and soybean) and weeds (pigweed and lambsquarters) of C3 and C4 species, whether of the pure culture or intercropping. The results of the experiment showed that, as the CO2 concentration increased, the leaf area and root dry weight of millet increased whereas those of other species decreased. Millet,s root length increased whereas those of other species decreased. Root dry weight in each cultural combinations, compared to the ambient CO2 concentration, decreased. The amount of chlorophyll in lambsquarters, increased whereas it decreased in pigweed, millet and soybean.

The aim of this study was to determine the concentration of free residual chlorine in the effluent at different concentrations of chlorine injection، between 50 to 350 ppm، at the pH levels of 6، 6. 5 and 7 and the effect of chlorination on pH، electrical conductivity and the concentration of total dissolved solids in drinking water and effluent. The results showed that the concentration of free residual chlorine changes by changing the concentration of added chlorine in the effluent samples. To achieve the concentration of free residual chlorine to more than 1 ppm at drinking water، effluent samples at pH levels of 6 and 6. 5 and effluent at pH of 7، 1، 150 and 200 ppm of chlorine was used. By reduction of effluent pH from 7 to 6-6. 5 the amount of added chlorine to achieve free residual chlorine concentration at 1 ppm، decreases in 25 percent. Adding chlorine in liquid sodium hypochlorite form to drinking water and effluent samples at all pH levels، increased electrical conductivity، the concentration of total dissolved solids and pH. The use of liquid sodium hypochlorite for chlorination of drip irrigation systems reduces the risk of biological obstruction but increased concentrations of dissolved solids، salinity and pH of irrigation water that increases the risk of chemical obstruction of emitters.

Irritable bowel syndrome (IBS) is a chronic functional disease of gasterointestinal system with nonspecific symptoms such as recurrent abdominal pain or discomfort associated with change in bowel habits (constipation¡ diarrhea or alternating periods of both) without any pathology in organs. According to previous studies prevalence of IBS varies among students.
The aim of this study is to assess the prevalence of IBS among medical students of Zabol University of Medical Sciences based on their educational status.
The study was performed on 106 students of the Medical University of Zabol in 1392 and samples were evaluated by questionnaire ROME III criteria and results were analyzed using SPSS21 software.
Of 106 cases 58.49% (62 cases) were male and 41.51% (44) were female. The mean age of students was 22.16 ± 0.04. The prevalence of IBS in students was 13.2%. Among them 54 cases were students in basic section period and 52 cases were students of advance section and the prevalence of the disease were 9.2% and 71.7%; respectively (P > 0.05). Non-native students had more prevalence of IBS (22.4%) than native students (5.2%) (P The prevalence of IBS was higher in our study comparing previous studies performed in Iran especially in non-native students. Further studies need to be performed longitudinally with larger sample to assess the exact prevalence and its related factors among student of different medical fields.