فهرست مطالب t. sohrabi

The aim of this study was to investigate the effects of dietary supplementation of a commercial probiotic containing Bacillus subtilis, Lactobacillus acidophilus, L. delbrueckii, L. rhamnosus, and L. plantarum on growth performance, hematological and immunological parameters of bester fingerlings. Two-hundred and forty fingerlings (10±0.9 g) were randomly distributed into 12 fiberglass tanks. The experimental diets were formulated using 0 (control), 100 (T100), 200 (T200), and 300 (T300) mg/kg of the probiotic. The fish were fed at 3% of body weight for 8 weeks. The result revealed that dietary probiotics increased final weight, condition factor, daily growth rate, specific growth rate, and body weight increase (p>0.05). Also, we observed a significant increase in feed efficiency ratio and protein efficiency ratio for fish fed with T300 compared to T200 (p<0.05). Hematological parameters were not influenced by dietary probiotic levels (p>0.05). There were no significant differences in total immunoglobulin (p>0.05), while alternative complement activity was significantly enhanced by the inclusion of probiotics in diets (p<0.05). The present study showed that feed efficiency, protein efficiency, and immunological parameters of bester fingerling have been improved by adding the commercial probiotic at 200 mg/kg.

Identifying blood supply chain risks can be effective to avoid failures that may affect the entire supply chain. The purpose of this research is to identify and rank the risks affecting the blood supply chain in the Corona virus pandemic.

In this study, 37 risks were identified based on the background of the research and interviews with 7 experts who had management positions in blood centers. Then, by distributing a researcher-made questionnaire among 113 employees of blood centers, the probability of occurrence and the severity of the impact of risks on the variables and value of each risk were calculated, and 21 critical risks were selected by using the risk matrix. Finally, the risks were weighted and ranked by pairwise comparison method using Expert Choice 11 software.

The results showed that the level of blood collection with a weight of 0.417 bears the highest risk in the blood supply chain. Risks of blood collection planning error (weight = 0.192), failure to comply with safety during blood donation (weight = 0.124), inaccurate information and creating false excitement (weight = 0.09), planning error demand (weight = 0.072) and blood shortage (weight = 0.072) ranked first to fifth.

Conclusions  :

The level of blood collection and as a result the amount of bloodstock bears the greatest risk in the corona pandemic, which can be largely avoided by planning for appropriate information sharing and preventing the creation of false emotions. This can greatly reduce negative effects on the blood supply chain.

In order to investigate the effect of chemical and biological nitrogen fertilizer on canola, a field experiment was conducted as a split plot based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture, Yasouj University, located in Deshtrum region, in 2019. The main factor consisted of nitrogen fertilizer (zero, 25, 50, 75, 100 and 125 kg/ha of pure nitrogen from urea source) and the secondary factor consisted of nitroxin biofertilizer contained Azotobacter and Azospirillium bacteria (use and non-use). The results showed that nitrogen fertilizer and nitroxin had a significant effect on all investigated traits. Nitrogen fertilizer significantly increased plant height, number of lateral branches, chlorophyll index and oil yield. The highest grain (8790.60 kg/ha) and biological (23910.93 kg/ha) yield were obtained in 125 kg/ha of nitrogen and the use of nitroxin. With the consumption of 125 kg/ha of nitrogen and nitroxin, the lowest percentage of seed oil, and contrastingly the highest percentage of seed protein (36.65%) was obtained. In general, combined application of biofertilizer with chemical nitrogen increased grain, biological and oil yield. Nitroxin bio-fertilizer could reduce the consumption of chemical nitrogen fertilizer. The results showed that there was no significant difference between the application of 50 kg/ha of nitrogen + bacteria and the application of higher levels of nitrogen (75, 100 and 125 kg/ha) alone in most of the investigated traits.

The main objective of this study was to evaluate the surface and deep distribution of Pb, Ni and Cu in the wastewater-irrigated area of south of Tehran using GIS and Hydrus. It was expected to find a comprehensive information of heavy metals distribution and their accumulation in the soil. This study was carried out in wastewater-irrigated area of south of Tehran. Soil sampling from the top surface layer (0-15 cm) and wastewater channels was done. After sample analysis, ordinary Kriging method using different variogram in GIS was applied to explore the surface distribution of Ni, Pb and Cu heavy metals. Moreover, the deep percolation of heavy metals in the soil profile was simulated by Hydrus-1D in a duration of 210 days and the heavy metals concentrations in the soil were estimated. Exploration of the distribution of Pb using spherical model showed that the variation of this element was in the range of 20-70 mg/kg. This amount varied to 50-60 mg/kg for Cu and about 30 mg/kg for Ni. Moreover, the simulation of heavy metals deep percolation using Hydrus revealed that the most accumulation of heavy metals happened in the 0-15 cm soil surface layer and for deeper layer, this trend was descending. Comparing the concentration of Pb, Cu and Ni with the maximum allowable amounts of WHO standards demonstrated that Pb concentration was more than the threshold limit. Finally, the applied models could simulate soil’s heavy metals content for both surface and deep distribution in the studied area.

In this study, with measuring water uptake in different soil layers, the role of different parts of root system in crop water supply during water stress conditions is characterized. Four cylindrical lysimeters with 25 cm diameter and 100 cm height were filled with clay loam soil. Soil columns were separated to 4 layers with 3 cm sand layers. Subsurface irrigation was applied with water stress patterns (decreasing number of layers which were irrigated from subsurface). Sand layers in each column which were preventing soil moisture exchange, could characterize the real role of each sub-layer root in water uptake when surface layers were under water stress. In this study root water uptake equation is corrected for water stress condition with presenting a compensation factor. With this corrected equation root water uptake in soil layers under water stress condition is investigated. The results showed that corrected equation determined root water uptake better than other equations in some conditions. Compensation factor is dependent on a plant factor (), that was determined with inverse optimization technique from root water uptake data in each lysimeter (it is calculated as 1.1, 1.87, 2.23 and 2.38 for lysimeters 1, 2, 3 and 4, respectively). This factor increased with increasing water stress severity.

During recent years, worldwide concern has been focused on the potential for contamination of surface waters and ground waters by agrochemicals in runoff and soil water from irrigated fields. Given this perspective, it is very important to correctly evaluate the levels of different agrochemicals in water, both from human toxicological and environmental viewpoints and to develop management strategies for reducing agrochemical loads to acceptable levels in the environment. The main objective of this study was to assess the qualitative changes of tailwater due to the use of agrochemicals and thereby to determine contamination loads. Four farms (A, B, C and D) were chosen in the Foumanat region in the F2 unit in 1996. The areas of these fields ranged from 0.22 to 0.6 ha having a number of unequal successive basins with variable inflow and outflow rates. A quantitative analysis showed that the tailwater ratio in farms A, B, C and D ranged from 2 to 64% during the irrigation season. The outflow water was classified as C3S1. The changes in qualitative factors were not significant and did not follow any certain pattern during the irrigation season. The changes in SAR, EC, Cu, Zn, B, P, K and DO in the inflow and outflow waters were also insignificant. After fertilizer application, the increase in nitrogen concentration in the outflow was significant. The average pollution loads in the inflow and outflow were about 1618 and 1476 kg/day/ha, respectively. The remaining load in the rice fields was about 142 kg/day/ha, which was meaningful at 1% level. The fifth farm (E) located in Lahidjan was sprayed with diazinon. Water samples were analyzed each day for diazinon residues for 10 days after application. Sample analysis showed that the concentration of the insecticide was 93.08 mg/l immediately after application and gradually reduced to 0.98 mg/l ten days after spraying.

The purpose of this research is to determine the application efficiency of rice irrigation plots and to analyze the reasons for low efficiency. The study will also try to determine the effective factors which could increase the application efficiency of rice fields. The selection of rice fields was based on climate, soil characteristics, and farmer management. Water application efficiency was determined by field measurements in three modern irrigation networks named Fouman (F), Rasht (G) and Lahidjan (D). In the meantime, a traditional network was included for comparison. In the study areas, the soil texture was heavy with an infiltration rate of less than 3 mm/day. The study was carried out under two different conditions: (1) without return flow and (2) with return flow. In the first case, the average application efficiencies in Fouman (F), Rasht (G) and Lahidjan (D) were about 51.2, 49.0 and 49.4 percent, respectively and the maximum and minimum values were about ((52.6, 49.7)), ((50.7 , 47.3)), and ((50.7 , 48.0)) percent, respectively. In the second case, the average application efficiencies for the above-mentioned regions increased to 73.4, 73.3 and 72.4 percent, respectively and the maximum and minimum values were about ((74.3, 72.4)), ((74.3, 72.1)), and ((73.0, 71.5)) percent, respectively. Runoff ratios in the above-mentioned regions were 30, 33 and 31 percent, respectively. During growing period (from transplanting to harvesting), the average applied irrigation water was about 1130 mm (11300 m3</sup>/ha) and the average evapotranspiration was determined to he about 561mm.