According to decline in water resources availability and quality and also increases population growth, one of the most important strategic policies for food security is agricultural vertical development which can be achieved by improvement of water productivity. Deficit irrigation by employing alternate furrow irrigation is one of the methods of water management in the field that its application increases water productivity and yield per each irrigation water unit. This study was conducted to evaluate and simulate the alternate furrow irrigation for wheat using SIRMOD model. To reach these aim, some experimental data for Kerman Zenderooh agricultural and environmental research center during 2005-2007 were used. This research was based on randomized complete block statistical design with four treatments normal and alternate furrow irrigation method with two planting distances 50 and 60 cm (T50, T100, T60 and T120) in three replications. Evaluation results by model showed that efficiency of application, irrigation and distribution of water can be improved 2 times in alternate furrow method as compared to normal method. There were 4, 10, 27, 43 minutes difference between observed and computed data of water time advances in treatments T60, T120, T100 and T50, respectively. In total, observations showed that alternate furrow irrigation with a spacing of 60 cm (T120) is suitable for wheat, even in sandy loam soils. This increases the efficiency of application, irrigation and distribution.

The application of fertilizer through irrigation water (fertigation) is an efficient and cost-effective method in which crop yield increases while potential environmental problems related to conventional application methods reduced. In this study, distribution uniformity of fertigation in different furrow irrigation regimes is evaluated, a numerical fertigation model established, calibrated and validated. Conducted experiments includ: injection of fertilizer only during the first half of the irrigation event (FH), injection during the second half (SH) and injection during the entire irrigation event (T). These options were conducted under free draining as well as under blocked-end conditions with two replications. All the experiments were conducted through cutback method. Potassium nitrate was used as fertilizer in the experiments. Distribution uniformity of low half (DULH) and low quarter (DULQ) of water and fertilizer was assessed to evaluate different fertigation scenarios. A sensitivity analysis approach was also performed to assess the effects of longitudinal dispersivity parameter on overland solute transport. The results show that DULH has significantly differs within the three application times (FH, SH, T). That shows injection in the second half of the irrigation event is more appropriate than injection in the first half and during the entire irrigation event as based on the results. The best case is injection in the second half of the irrigation event preferably starting before completion of the advance phase and in blocked-end conditions. Because in this case, solute losses due to runoff from the outlet is zero and also distribution uniformity is somewhat higher whereas in free-draining conditions fertilizer application during the first half of irrigation provide acceptable fertilizer uniformity and least losses due to runoff. Results of the model show that the best case would be injection in the second half of the irrigation event with blocked-end conditions. No significant difference was observed between distribution uniformity of free-draining and blocked-end experiments. It was found that dispersivity parameter doesn't affect the fertigation uniformity. A value of 5 ern for dispersivity provided a reasonable fit to the experimental data.

Introduction: Sudden cardiac death is common in patients on hemodialysis and may occur in the immediate post dialysis period when ventricular premature complexes are common. QT dispersion reflecting hetovogelity in ventricle repolarization has been used for predicting patients with risk of malignant arrhythmia and sudden death. The purpose of the study was to assess the effect of hemodialysis on QT dispersion (QTd) corrected QT dispersion (QTcd) and maximum QTc (QTcMax) in chronic hemodialysis patients. Methods: In this deh1ive-analytic study data of 48 patients (30 male and 18 female patients with mean age 43±16 yr) on chronic hemodialysis were studied. 12 lead ECG were recorded 5-10 minutes before and after hemodialysis in a standard setting and Na+ K+ Ca++ Po4 and Mg++ levels were also determined pre and post hemodialysis. During hemodialysis no drug therapy was used except isotonic and hypertonic NaCl infusions and sodium heparin. The maintenance drug therapy including digitalis antihypertensive antianginal and beta blocking agents was not changed. The data were analyzed using SPSS software. Results: The maximal QTd interval changed significantly from 434±12.8 ms to 443±21.33 ms (P<0.001). The QTd increased significantly from 55.87±7.5 ms to 61.27±9.09 ms (p<0.001) and QTcd from 61.18±43 ms to 68.79±10.32 ms (p<0.001). 33.33% of the patients before and 47.90% after hemodialysis had QTcMax more than 440 ms.Conclusion: Hemodialysis incrases the QTd, QTcd and QTcMax in patients with end-stage renal failure, Tuse it is likely that heterogeneity of regional ventricular repolarization increases during hemodialysis.

Background: Nocturnal hypoxia is an important factor increasing the risk of mortality in patients with chronic heart failure and is associated with atrial and ventricular arrhythmias. QT dispersion, an index of myocardial electrical activity, is used as a prognostic tool in determining future malignant arrhythmias and sudden cardiac death. In the current study we investigated the effect of nocturnal oxygen therapy (NOT) on QTd in patients with CHF.Materials and methods: In this clinical study 54 patients with CHF (EF≤40%) were enrolled. Patients were administered NOT; electrocardiography was taken before and after NOT and QTd measured each time. Paired t-test was used to compare pre- and post-NOT QTd.Results: QTd significantly decreased from 56.3±18.2 msec before NOT to 46.3±17 msec after NOT (p=0.001).Conclusion: In this study NOT decreased QTd in patients with CHF which could consequently decrease risk of malignant arrhythmias and sudden cardiac death. However, the mechanisms by which NOT decreases QTd is not clear and requires further investigation.

It is of great interest and remains a challenge to simultaneously improve the compatibility and flame-retardant performance of lignin/epoxy resin (EP) composites. In this work, a polysiloxane-enwrapped phosphorus-containing lignin-based flame retardant (PHMS-lig-P) was prepared through reactions of lignin, PHMS and TCP to address this issue, with results showing significantly improved flame-retardant performance and comprehensive performance. The influence of PHMS-lig-P on the flame retardancy of EP was investigated by vertical burning test (UL-94V), limiting oxygen index (LOI), smoke density test and cone calorimeter (CC) test. The PHMS-lig-P/EP achieved a V-1 rating, and its LOI value increased to 25. 3%. The maximum smoke density (Ds, max) decreased by 83. 2%. Furthermore, pHRR, avHRR, and MLR of PHMS-lig-P/EP decreased by 37. 5%, 22. 6%, and 25. 1%, respectively. In addition, the evolved gases and char residues were studied using thermogravimetric analysis coupled with Fourier transform infrared spectrometry (TG-FTIR) and scanning electron microscopy (SEM). The results certified the flame-retardant mechanism of PHMS-lig-P was attributed to the synergistic effect of lignin, phosphonate, and polysiloxane, producing a compact and cohesive char layer that acted as a physical barrier, limiting the transfer of heat and oxygen and preventing the spread of pyrolysis volatiles and flammable gases. Moreover, the flame-retarded epoxy resin possessed good dispersion uniformity in mechanical properties and insulation performance, showing good applicability.

Flow distribution uniformity in manifolds is important in various engineering applications. In this study, the effect of manifold design on flow distribution is examined using both experimental and numerical methods. A comparison was made between a straight manifold and a gradually decreasing cross-sectional design considering two different inlet diameters. In addition, the staggered manifold case with the most homogeneous outlet was compared with the conical manifold under the same conditions. The results demonstrate that the gradually decreasing manifold design significantly improves the flow rate uniformity compared with the straight manifold. This improvement is achieved by reducing the flow rate differences between the distribution branches, leading to a more balanced fluid distribution. The gradual reduction in the cross-sectional area allows the fluid to traverse at lower velocities in regions with higher resistance, effectively minimizing flow rate discrepancies and pressure drops. In addition, the effect of varying the inlet diameter on flow rate uniformity was investigated, revealing that larger inlet diameters contribute to improved flow distribution. The outlet uniformity of the staggered manifold matches the effective performance of the conical manifold, demonstrating similar performance at a lower cost. The results highlight the importance of designing an appropriate manifold, considering factors such as inlet diameter, channel geometry, and staggered ratio, to achieve efficient and uniform fluid distribution.

An Adaptive Quality Control Phantom (AQCP) was designed and constructed to perform QC tests. AQCP is the computerize phantom which moves a radioactive source in the FOV of an imaging Nuclear Medicine device on a definite path to produce any spatial distribution of gamma rays to simulate QC phantoms. Systematic uniformity test was performed by AQCP and the result compared with classic method and the differences have been discussed in details. The results show AQCP method has some advantages such as: Reduction in radioactive material consumption, radiation exposure to staff and systematic uniformity test.