Production of gold nanoparticles by Streptomyces djakartensis isolate B-5

Biosynthesis of gold nanoparticles [NGPs] is environmentally safer than chemical and physical procedures. This method requires no use of toxic solvents and synthesis of dangerous products and is environmentally safe. In this study, we report the biosynthesis of NGPs using Streptomyces djakartensis isolate B-5. NGPs were biosynthesized by reducing aqueous gold chloride solution via a Streptomyces isolate without the need for any additive for protecting nanoparticles from aggregation. We characterized the responsible Streptomycete; its genome DNA was isolated, purified and 16S rRNA was amplified by PCR. The amplified isolate was sequenced; using the BLAST search tool from NCBI, the microorganism was identified to species level. Treating chloroauric acid solutions with this bacterium resulted in reduction of gold ions and formation of stable NGPs. TEM and SEM electro micrographs of NGPs indicated size range from 2- 25 nm with average of 9.09 nm produced intracellular by the bacterium. SEM electro micrographs revealed morphology of spores and mycelia. The amplified PCR fragment of 16S rRNA gene was cloned and sequenced from both sides; it consisted of 741 nucleotides. According to NCBI GenBank, the bacterium had 97.1% homology with Streptomyces djakartensis strain RT-49. The GenBank accession number for partial 16S rRNA gene was recorded as JX162550. Optimized application of such findings may create applications of Streptomycetes for use as bio-factories in eco-friendly production of NGPs to serve in demanding industries and related biomedical areas. Research in this area should also focus on the unlocking the full mechanism of NGPs biosynthesis by Streptomycetes

[Smoking behavior among male student's bases on trans theoretical model]

Smoking is a global health problem both, in developing and developed countries. Theoretical model has been developed for understanding of behavior change especially addictive behaviors, not only delineates a way to conceptualize behavior change, but also it provides the foundation for developing assessments of an individual's readiness to change and for tailoring interventions to actualize behavior change. In a cross-sectional study and a convenience sample of 578 smoker and ex-smoker From 6 universities during December, 2009 to June, 2010 completed three Persian versions of the short form Smoking questionnaire based on trans theoretical model developed by Prochaska, Velicer and Diclemente. Data were analyzed using descriptive statistics and ANOVA test. More than half of the subjects were in the precontemplation stage. The pros of smoking among subjects in the precontemplation stage were significantly higher than subjects in the preparation and maintenance stages [P<0.05]. Meanwhile, the pros of smoking ratings were significantly higher for the contemplation and preparation stages than for the maintenance [P<0.05]. However, pros of smoking in the action stage were not significantly for the other stages of change [P>0.05]. Significant mean differences in cons of smoking behavior emerged across the stages of change. In terms of self-efficacy/temptation construct, the result showed significantly difference between the stages of change [P<0.05]. The results provided support of advantages of increase self-efficacy and the role of decisional balance for the intervention programs development in smoking cessation