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The time required for deep percolating water to reach the water table can be considerable in areas with a thick vadose zone. Sustainable groundwater management, therefore, has to consider the spatial and temporal dynamics of groundwater recharge. The key parameters that control the lag time have been widely examined in soil physics using small-scale lysimeters and modeling studies. However, only a small number of studies have analyzed how deep-percolation rates affect groundwater recharge dynamics over large spatial scales. This study examined how the parameters influencing lag time affect groundwater recharge in a semi-arid catchment under irrigation (in northeastern Iran) using a numerical modeling approach. Flow simulations were performed by the MODFLOW-NWT code with the Vadose-Zone Flow (UZF) Package. Calibration of the groundwater model was based on data from 48 observation wells. Flow simulations showed that lag times vary from 1 to more than 100 months. A sensitivity analysis demonstrated that during drought conditions, the lag time was highly sensitive to the rate of deep percolation. The study illustrated two critical points: (1) the importance of providing estimates of the lag time as a basis for sustainable groundwater management, and (2) lag time not only depends on factors such as soil hydraulic conductivity or vadose zone depth but also depends on the deep-percolation rates and the antecedent soil-moisture condition. Therefore, estimates of the lag time have to be associated with specific percolation rates, in addition to depth to groundwater and soil properties. [ABSTRACT FROM AUTHOR]

Purpose of the study: to determine the efficacy, adverse effects and safety of a new Iranian generic product of deferasirox (Osveral®) in Iranian transfusion dependent major thalassemic (TD-MT) patients. Methods: In 9 main thalassemia treatment centers, all of TD-MT patients (aged ≥2 yrs) with serum ferritin (SF) levels ≥1000 ng!ml, or >100 ml/kg of RBC transfusion ,who could not tolerate parental iron chelating were recruited regardless of their previous iron chelation therapy. Periodical clinical and laboratory evaluations were conducted for adverse effects (AEs). Primary efficacy end point was Mean of Relative Change of Serum Ferritin (MRC-SF) from the baseline level during one year. Analysis of variance (ANOVA), t test, chi-square or Fisher exact test were used for statistic analysis appropriately (P values <0.05 were considered as statistical significant). Results: In 407 cases the male/female ratio was 0.98. Mean age was 11.5±7.4 (2-58) years. The mean of initiating dose of Osveral® and mean usage dose during the study was 23.5±4.9 mg/kg and 24.9±4.9 mg/kg respectively. MRC-SF was -11.44% ±38.92 and it showed significant decline in SF (P value<0.001) one hundred and forty eight patients out of 407 patients experienced at least one. AE, the most common of them were transient increase in serum creatinin (97;24.1%) and > 5 time increase in transaminases (24;5.89%).The causes of discontinuation of treatment were non-satisfactory treatment (24; 5.8%), poor or non- compliance of patients (21 ;5.1%), and adverse effects (13; 3.1%). Conclusion: A detailed comparison with similar studies on deferasirox (Exjade®) shows a promising efficacy and safety for its Iranian generic product (Osveral®). [ABSTRACT FROM AUTHOR]