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This study was carried out in order to measuring Hg in some varieties of the most consumed imported and most locally cultured rice and comparing together and assess potential health risk. The correlation between Hg content of soil and rice samples, and effect of cooking and washing treatment on Hg concentration in rice, were investigated. In November 2008, locally most cultured rice and soil samples were collected from the Mazandaran province. High consumption of imported Indian rice with commercial brands collected from source, according to purposed method of standard office of Hormozgan. Advanced mercury analyzer Leco AMA 254 used to determination of Hg levels. The results showed that Hg concentration in Iranian rice (0.044 ± 0.003 µg g^-1 d.w) significantly over imported rice (0.039 ± 0.001 µg g^-1 d.w). Comparing the tolerable daily intakes (TDI) given by FAO/WHO with the mean estimated daily intakes (EDI) through rice consumption in this study was lower than TDI. In addition, results showed that no relationship was found between Hg concentration in rice and soil samples (r= 0.079, p=0.567), and cooking and washing treatment has not significant effect on mercury concentration. Finally, relationship between Hg concentration in soil and rice samples with soil parameters were studied that was not observed any correlation.

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Listeria monocytogenes is one of the most dangerous bacteria in food products which caused about 20 to 30% fatalities. One of the major foods which caused listeriosis is ready to eat (RTE). So, appropriate heating processing methods are need for elimination of L. monocytogenes. These bacteria has ability entering into viable but nonculturable (VBNC) form in unfavorable conditions. So this investigation was aimed to considering behavior of this pathogen at higher temperatures from recommended for elimination of these bacteria. For this purpose, bacteria in 5×10⁶ counts in mid log phase were inoculated into two medium BHI Broth and fish Broth (FB) and they exposed to 85 ºC for 10 minutes. Direct plate count on listeria choromogenic agar, BacLight^® Live/Dead and gene expression of 16S rRNA, the housekeeping gene, were done before and after heat shock. The results show that these bacteria lose their culturability during high heat shock. The results of fluorescent dyes showed the viability of these bacteria after heat shock (p< 0.01). The results of gene expression considering confirmed the results of fluorescence dyes and showed that 16S rRNA gene was expressed in nonculturable bacteria. According to these results, there is a big question on the D value on quality control for these bacteria in food processing processes, especially for RTE foods.

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In this study, the extract of Entromorpha intestinalis was exctracted using different solvents including water, chloroform, methanol, ethanol, hexane and acetone. Antibacterial and antifungal properties of these extracts were evaluated using a modified disk diffusion method. Microorganisms investigated in this research were included Gram-positive bacteria Lactococcus  lactis, Listeria monocytogenes, Bacillus subtilis, Gram-negative bacteria Escherichia coli and fungi Candida albicans. According to the results, the methanol and hexane extracts of this alga had the best activity against L. lactic. (p<0/05). Methanol and ethanol extracts had the best activity against L. monocytogenes (p<0/05). But for the others tested microorganisms  in this study, the extract of aceton exhibited the best inhibition zone (p<0/05). The extract of E. intestinalis possesses good antibacterial and antifungal activity against the investigated microorganisms and it could also used as a suitable natural antimicrobial compound.

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Economic value of the rice product is determined by the quality of rice after paddy conversion operation to white rice. Conversion Coefficient and crack percent are two important indices for determining the quality of rice after conversion operation that type of dryer used is effective on level of these indices. In this study effect of air temperature was studied in four levels (40, 45, 50 and 55°C); final moisture in three levels (8-10, 10-12, and 12-14%) and rice variety in three levels (Tarom-domsiah, Hashemy, Shirudy) on crack percent and conversion coefficient during the drying in a fluidized bed dryer. Experiments were conducted in the factorial design with three replications and three factors 3×3×4. Results showed that conversion coefficient of Tarom-domsiah, Hashemi and Shiroodi varieties reduced with increasing of moisture at all four temperature levels. In order to dry rice, temperatures 40°C and 50°C for Tarom-domsiah variety and temperature 55°C for Shiroodi variety lead to the best conversion coefficient. Crack percent of Hashemi variety increases with rising of drying temperature but crack percent of Shiroodi variety is reduced. Minimal crack percent of Tarom-domsiah, Hashemi and Shiroodi varieties is gained at temperatures (45°C and 50°C), 45°C and 55°C respectively. Hence, it is recommended to use temperatures mentioned for drying of these varieties in order to obtain minimal crack content.

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The present research aims to investigate the effect of philosophy education on social problem solving and creativity of preschool children. The study is a quasi-experimental and conducted with pre- and post-test control group. The statistical population included preschool children of District 4 of Tehran. The sample consisted of 80 people who were selected in two-stage by random cluster sampling and were placed in two equal groups of experimental (40 subjects) and control (40 subjects). Torrance Diverted Thinking Test (1988) and Child Social Problem-Solving Test (2000) were administered as instruments. Both groups were evaluated in two stages of pre-test and post-test. Training sessions were conducted in 8 sessions, each with 45 minutes for the experimental group. Philosophy education was taught to children in all 8 sessions.  Data were analyzed using mean, standard deviation, and Multivariate Analysis of Variance by SPSS21. Results showed that Philosophy education had a significant effect on social problem solving of preschool children. The results also showed that Philosophy education had a significant effect on the creativity of preschool children (P≤0/05). According to ETA coefficient, the effect of education using the method of philosophical exploration circles on creativity (0.136) and on social problem-solving skills (0.079). Therefore, it is suggested that pre-school educators use this approach to develop social problem-solving abilities and enhance children's creativity.