فهرست مطالب علی اصغر هاشمی

The objective of current study was to invstigate the accuracy of Tyler and Wheatcraft, Bird et al. and Kravchenko and Zhang fractal models in describing particle size distribution (PSD) of sediment in 14 successive check dams for two depths of 0-15 and 15-30 cm. Sediment PSD were determined in 28 samples using hydrometer method . The referred fractal models were fitted on sediments PSD data. Results indicated that there was no regular relationamong fractal dimensions insuccessive check dams. In addition, sediments transport from surroundingsoils was more observable in check dams. Two-parameter models of Bird et al. and Kravchenko and Zhang presented a better fit compared to one-parameter model of Tyler and Wheatcraft. The results of statistical analysis proved that the sigmoid function was able to describe the relation between fractal dimensions and clay, sand and silt percentage with a greater accuracy compared to the linear sigmoid function. Stepwise regressionanalysisdetermined astrong and significant correlation (R2= 0.97**) between fractal dimensionobtained from Tyler and Wheatcraft modelwithclay and sandcontents. According the result of this study, the determination of sediment PSD is possible bymeasurement of clayandsand amount.

Influenza vaccination is one of the most important ways to prevent influenza acquisition in healthcare staff. This study was conducted to determine the cumulative incidence rate of side effects associated with influenza vaccination among healthcare staff in some of the hospitals in Shiraz.
This descriptive study was conducted on the staff of a number of hospitals in Shiraz who received influenza vaccine in 1392. Instrument in this study was a researcher-developed questionnaire about common side effects that was collected up to 10 days after the vaccination. Incidence of side effects was reported with 95% confidence interval. The data were analyzed by chi-square test, Fisher's exact test, and univariate logistic regression.
From the 450 vaccinated staff, 424 (94.23%) completed the questionnaire. 53.8% of vaccine recipients were female and 46.2% male. The mean age of the participants was 34.94 years. Up to 10 days after vaccination, cumulative incidence rate of side effects following vaccination was obtained 21.7% for common cold-like symptoms, 71.2% for muscle pain, 16.5% for pain where the shot was given, 15.3% for fever, 14.4% for runny nose, 12.3% for severe headache, 9% for severe coughing, 0.9% for diarrhea, and 1.7% for abdominal pain (1.7%). No severe side effects such as acute allergic reactions and Guillain-Barré syndrome were reported.
The reported incidence rate of side effects in this study, high risk of acquiring disease among health care staff, and their role in controlling influenza epidemics represent the necessity of influenza vaccination in this occupational population.

Due to successes of fingerprinting method in producing rapid and low-cost information of sediment sources, in this research this method was used in three sub-cathments of Chasht-Khoran Basin in Semnan Province: Amrovan, Atari and Ali-Abad. Samples below 63 μm were separated and 15 fingerprinting propertis was measured. In the first stage comparison of means and differentiation analysis were used for determination of the characteristics that can differentiate sediment source as well as possible. In second stage, by minimizing composite multivariate model by optimization methods, the share of each source was determined. The results shown that, in Amrovan Catchment, For properties consisting of Co, Ph, Kaolinite and K were recognized as optimum composition of sediment tracers which could differentiate sediment source completely. In Atary Catchment, the optimum composition of tracers are Na, Co, XLF and kaolinite which differentiate source by %91.7. In Ali-Abad Catchment five parameters were recognized as optimum composite which are: Na, XLF, Ca, Co and smectit which completely differentiated sediment sources. The results of calculated composite multivariate model have shown that Upper Red formation in Amrovan, Atari and Ali-Abad Sub-Catchment has the highest share in sediment production. The sediment production in these three sub catchment are as follows:35.9, 23.53 and 86.64% respectively. Therefore sediment management and control strategies should be performed on these sources.

Soil is considered as the most important natural resources of each country. Soil erosion is a serious hazard to human life. Soil erosion not only causes destruction of soil، but also causes much detrimental effects with sediments deposited in waterways، reservoirs and dams which reduce their storage capacity. These sediments، due to their physical and chemical characteristics have the highest erodibility. In this study، the physicochemical properties of marl units on soil erosion have been determined on 31 samples in marl lithologic units based on erosion shapes and thru dominant slopes. Soil physical and chemical properties were determined by standard analytical methods. Analysis of variance and comparing of means was performed. Finally، the factor analysis was used to separate the affording factors on erosion shapes. Erosion increased with increasing SAR، EC، Na، Cl، SO4، silt and clay and decreased with increasing in HCO3، TNV and gravel. EC، SAR، Na، Cl، TNV، HCO3، SO4، gravel، silt and clay have statistically significant difference between erosion types and factor analysis showed that EC، SAR، Na، Cl، silt and clay booster and HCO3، TNV and gravel are halter factors of erosion.

The Marls are unstable sedimentary formations that contain chemical materials and destructive particles. Marls Erosion processes are very intensive, so different forms of erosion on the marls as badlands are of specific characteristics in marl lands. Hence, recognition of effective characteristics in marls erodibility is necessary to adopt corrective measures and methods. In this research, for assessing marls erodibility in Hablehroud watershed portable rain simulator was used. Runoff and sediment amounts were measured in each marl unit. Then effective Factors were identified using statistical parameters. Finally, by factor analysis we determined the relationship between marls chemical properties and sediment yield. Therefore, effective parameters of erosion and sediment yield were determined. Results showed sediment yield is decreased in gypsum marl, sandy marl, salt marl and limy marl. In addition, erosion and sediment yield are increased with increasing EC, Na, Cl, SAR and with decreasing TNV, HCO3

In this research، is reviewed the role of physical and chemical characteristics of the marl units on erosion extension. The sampling is done from 4 marl lithology، based on erosion shape and dominant area slope. In order to verification of marl units sediment we used of portable rain simulator. Measurement of sediment، runoff and soil physical and chemical analysis from each of the marl units was done. Analysis of variance and the mean was used for data analysis. With use of factor analysis، we establish relationship between chemical characteristics of marls and sediment، and then determine effective factors on erosion and sediment. According to the statistical parameters، erosion increase with increase of SAR، EC، Na، Cl، SO4، silt and clay and decrease in HCO3، TNV and gravel. Also، EC، SAR، Na، Cl، TNV، HCO3، SO4، gravel، silt and clay has significant difference between erosion types. Factor analysis results showed that erosion intensity and sediment increase with increase in SAR، Cl، Na، EC and decrease in HCO3، TNV.

One of the greatest problems in Sorkheh artificial recharging system of Semnan province is the high amount of sedimentation into the system. Erosion of marl deposits around Sorkheh artificial recharging system supplies the main part of total sediments. Recognition of sensitivity to erosion and identifying effective factors such as physical and chemical properties and atterberg limits in marl deposits is the main target of this study. With reducing of sediment sorting and increasing of density, resistance to erosion of marl deposits increase. Such as effective main variables in eredibility are medium sand, medium silt and clay contents. Medium sand and medium silt increase both sorting and erosion index and ultimately reducing of density. These sizes of particles in marl units in rill erosion show the highest frequency. In the other hand, with increasing of clay parts, occurred opposite of above phenomenon. The highest frequency of this variable has observed in the low to moderate and high intensity of surface erosion. The obtained results were analyzed with factor analysis by Principal axis Factoring method. With this method, the two decreasing and increasing erosion factors are separated from together and confirm previous results.