e. salimi

The impacts of nanoparticles in radiation therapy have been investigated during the recent decades. The present study was conducted with the aim of investigating the effect of different physical interaction models on dose calculations using gold, hafnium and gadolinium nanoparticles. A nanoparticle with a diameter of 50 nm was simulated in a cubic water phantom and irradiated by protons with the energies of 5, 50 and 150 MeV using Geant4 Monte Carlo toolkit. The current study has considered various parameters, including the energy spectrum of secondary electrons and photons, radial dose distribution (RDD), dose enhancement factor (DEF), around the nanoparticle with three different materials and two physical interaction models. The obtained data showed that for gold nanoparticles, the Penelope model generated a greater number of secondary electrons than the Livermore model; however, for the other two nanoparticles, the Livermore model produced a greater number of secondary electrons than the Penelope model. In the RDD graphs, the Penelope model presents a 10% difference compared to the Livermore model up to a distance of 6 nm from the nanoparticle’s surface (along the radial axis in water). Furthermore, the Livermore model indicates a 16% and 10% increase in dose compared to the Penelope model up to a distance of 9 nm from the surface of hafnium and gadolinium nanoparticles, respectively. In the case of DEF, the dose deposited around the gold nanoparticle was increased by 14, the highest amount compared to DEF of hafnium and gadolinium nanoparticles which is 10 and 6, respectively

The present research has endeavored to identify the flaws in the human resource management system in Iran's educational administration and resent suggestions for improvement. Quantitative in nature, this study has taken a descriptive approach regarding its objective while the approach toward data collection has been of the survey kind. Teachers and principals of state-owned schools in the province of Tehran constituted the statistical population, and the sample has been selected by means of random multistage clustered sampling. The system flaws have been identified in four areas – recruitment and securement, training and improvement, maintenance and the deployment of human resources. Thus, exploratory interviews were conducted with experts on Iran’s educational system, and the research questionnaire was devised based on relevant theoretical foundations. For data analysis, LISREL and SPSS software were used, and confirmatory factor analysis and the one-sample T-test were used. The findings indicate that, as seen by teachers and principals, when it comes to retaining staff, the most important flaws occur in the components of salary, benefits and security, while in the domain of training and improvement, performance assessment is the main component, and in the field of deployment, motivation is the main component. Inappropriate indices of ranking and performance assessment, inadequate salaries and benefits compared to other executive branches of the government, the lack of legal support such as civil liability insurance for teachers and the absence of a career path system can be named as some of the flaws.

Disability, reduces quality of life and independence of older adults and increases their needs to giving caring support. This study was conducted to assess the disability status in the rural older adults in Ilam.

This descriptive-analytical study, was conducted using a two-stage cluster sampling method on 70 older adults who aged 65 years and over in rural areas of Ilam in 2015.WHODAS II questionnaire was used to evaluate disability status in activities of daily living. Data were analyzed by SPSS software version 21andusing T-Test and ANOVA.

The findings showed that (21/4%) 15 of older adults had no disability, (25/7%) 18 of them had low disability, (47/1%), 33 of them had moderate disability and only (5/8%) 4 had severe disability. Most disabilities related to job activities and walking, and the lowest ones related to the social and familial activities and interaction with people respectively. Also level of disability had a significant relationship (p 0/05).

Most of rural older adults in Ilam had moderate level of disability. So there is a necessity for promotion of healthy lifestyle programs by health care professional with the aim of reducing and prevention of disability in older adults.