سمیه کاظم پور

The general purpose of this research is to determine the relationship between the organizational health of schools and human health with the academic vitality of female students in second grade high schools in east of Gilan province.

The current research was conducted using a correlational method, in which human health and organizational health were considered as predictor variables and academic vitality was considered as a criterion variable. The statistical population of this research included all the female students of the second grade high schools in east of Gilan province, numbering 10392 people. According to the table of Krejcie and Morgan, 373 people were selected as a sample through stratified random sampling method. To collect data, three researcher-made human health questionnaires (Hedayati et al., 2021) with a reliability of 0.96, a standard organizational health questionnaire by Hoy and Feldman (1997) with a reliability of 0.91, and an academic vitality questionnaire (Dehghanizadeh et al., 2014) ) were used with a reliability of 0.80, which had good validity and reliability. The obtained data were analyzed using spss software. At the descriptive and inferential level, the K-S test was used for the normality of the data and the Pearson correlation coefficients and step-by-step regression were used to test the research hypotheses.

The findings of this research indicated that there is a direct relationship between predictor and criterion variables in this research.

As a result, it can be said that there is a relationship between the organizational health of schools and the human health of students with their academic vitality, so that if organizational health in schools and human health in students increases, students' academic vitality will also increase.

Since abandoning public corporations on the other hand, transferring to private is proceeding in recent years, therefore this research follows investigating and comparing public and private enterprises performance in Tehran stock exchange corporations through out economic value added (EVA) and return on asset (ROA) criteria.The domain of this query is 1383 to 1386 and population includes all of Tehran stock exchange corporations. Forecasted sample size for 4 years for this research equals 160 cases that 40 competent cases from 181 cases is sampling.Result of statistical analysis illustrate that direct relation between private ownership ratio and return on asset and economic value added also about 0.14 EVA changes and about 0.7 ROA changes are explained by private ownership ratio, besides the relationship between ROA and EVA is directive and significant.

Plants absorb radioactive elements from phosphate fertilizers, and also from naturally occurring radiation in the soil, air and water. It has long been known that low doses of ionizing radiation evoke stimulatory effects in a wide variety of living organisms. However, as far as we know, there is no published report on the bio-positive effects of diagnostic doses of X-rays on plant growth. The aim of this study was to evaluate the bio-effects of low doses of diagnostic X-rays on growth rate of Phaseolus vulgaris (Pinto) plants. Before cultivation, Phaseolus vulgaris (Pinto) seeds were soaked in tap water for 2 days followed by another 2 days of covering under a wet cloth. Four hundred newly cultivated seeds were randomly divided into two groups of 200 plants each. In this experiment, two seeds were cultivated in each dish (100 dishes for irradiation group and 100 for sham-irradiation group). Fifteen days after starting cultivation, newly grown plants were irradiated with X-rays. Plants were exposed to a single dose of X-ray (80 kVp, 80 mAs) for 6 days. On day 29, plants were pulled out from the soil. Length of plant stem, length of root, number of leaves and plant weight were measured. The stem length in irradiated and sham-irradiated plants was 296.51±13.57 and 223.96±15.02 mm respectively. This difference was statistically significant (P<0.001). Although the number of leaves in irradiated plants was higher than that of sham-irradiated plants (7.05±0.18 and 6.74±0.19 respectively), the difference was not statistically significant. The stem diameters in irradiated and sham-irradiated plants were 3.52±0.12 and 3.35±0.09 mm respectively, but the difference again was not statistically significant. Plant weight in irradiated samples was less than that of non-irradiated plants but it was not statistically significant. The overall results indicate that diagnostic doses of X-rays can accelerate the growth of plants. The growth enhancement ratio for stem length was 1.33 that is a challenging figure. However, current data seem to be insufficient and further studies are needed to confirm these findings as well as to find out the possible hormetic mechanisms.