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The Kor River in Fars province supplies an important part of water requirement in the Doroodzan dam basin and its surrounding area. In this study, the meteorological and hydrological droughts of this area were investigated in the last four decades. For this purpose, the temporal and spatial trend variability of the stream flow was investigated in monthly, seasonal, and annual time scales in the 6 selected stations. The trends of Standardized Precipitation Index SPI, as the drought index, in the 5 selected stations were also studied by the modified Mann-Kendall method. The results indicated that the trend in the stream flow was decreasing in all time scales. Significant downward trends were observed at 95% confidence level on monthly, annual and monthly time scales, especially in the warm months from May to September. These significant downward trends were located spatially in the stations located near the agriculture area, in the middle part of the basin. The significant upward trend existed only at the Doroodzan dam station, at the outlet in the area and in the warm months of the year. In the case of the SPI index, trends were decreasing in all time scales and were significant only at 2 stations in the long-term periods, 9, 12, and 18 months, at 95% confidence level. The results, therefore, indicated the occurrence of severe droughts (SPI

Soil erosion is undoubtedly one of the most important problems in natural areas of Iran and has destructive effects on different ecosystems. Considering that calculation of the sediment rate in sediment stations and direct measurements of erosion process is costly and difficult, it is critical to find ways to accurately estimate the amount of sediment yield in catchments especially in arid and hyper arid areas because of their high ecological sensitivity. One of the most commonly used methods in these areas is the sediment rating regression method. Therefore, in this study sediment observed data for 48 events (the corresponding discharge and sediment) in a 23-year period from Fkhrabad basin (Mehriz) were compared to the estimated data obtained from Multi-line rating method, extent middle class, middle class rating curve with correction factor QMLE, SMEARING correction coefficient FAO and Artificial Neural networks (ANNs). Finally, the accuracy of these methods were assessed using different evaluation criteria such as Root Mean Square Error (RMSE), coefficient of determination (R2) and the standard Nash (ME). Results showed that ANN outperformed the other methods with the RMSE, R2 and ME of 203.3, 0.86 and 0.66, respectively. The results suggest that these methods should be used cautiously in estimating the suspended sediment load in arid and hyper arid regions due to the nature of the observed data and temporal and seasonal flow systems in these regions. It was also indicated that the artificial neural network models have higher flexibility than other methods which makes them to be useful tools for modeling in poor data conditions.

Background & aim: Pentoxifylline is an immunomodulatory and anti-inflammatory agent which inhibits the production of proinflammatory cytokines. The purpose of this study was to evaluate the effect of pentoxifylline in the treatment of type 1 diabetes in mice and its effect on the expression of peroxisome proliferator- activated receptor gamma (PPARγ). Methods: After induction of diabetes in male C57BL/6 mice, they were treated with Pentoxifylline (100 mg/kg/day) for 21 days. Blood sugar levels were measured on days 0, 7, 14 and 21. Splenocytes were tested for cytokines production by ELISA. Further investigations on immune system changes in spleens were tested by semi-quantitative RT-PCR on PPARγ gene. Statistical data were analyzed using the Student t-test and ANOVA. Results: Treatment with pentoxifylline prevented the level of blood sugar in diabetic rats. Pentoxifylline treatment also significantly inhibited the production of proinflammatory cytokines IL-17 and IFN-γ, while cause increasing the anti-inflammatory cytokine IL- 10 and the expression of PPARγ gene in the spleen compared to the diabetic control group (p< 0.05). Conclusion: Due to STZ induction, Pentoxifylline may have therapeutic effects against autoimmune destruction of pancreatic beta cells on type 1 diabetes in mice

The indigenous knowledge of our ancestors provides valuable information on how to prevent negative health impacts on water hygiene in the event of drought. The present study aimed to explore the role of indigenous knowledge in maintaining water safety in drought conditions. A qualitative content analysis method using in-depth semi-structured interviews was used to collect and analyze the data. The current research was carried out from April 2017 to June 2018. A purposive sampling method was used to select 15 participants. Trustworthiness was applied with the Lincoln and Guba approach and data were analyzed using Graneheim and Lundman's method. Two categories including drinking water storage and water collection were extracted from the data. Each category includes different strategies to deal with water. Water storage includes water quantity and water quality. Water collection consists of collection methods and rules. Indigenous knowledge is an indispensable component of community disaster resilience. It can be transferred to other communities and employed to empower affected communities. But using the knowledge without scientific considerations cannot guarantee peoples' health throughout the drought periods.