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Concerns about health problems due to the increasing use of mobile phones are growing. Excessive use of mobile phones can affect the quality of sleep as one of the important issues in the health literature and general health of people. Therefore, this study investigated the relationship between the excessive use of mobile phones and general health and quality of sleep on 450 Occupational Health and Safety (OH&S) students in five universities of medical sciences in the North East of Iran in 2014. To achieve this objective, special questionnaires that included Cell Phone Overuse Scale, Pittsburgh's Sleep Quality Index (PSQI) and General Health Questionnaire (GHQ) were used, respectively. In addition to descriptive statistical methods, independent t-test, Pearson correlation, analysis of variance (ANOVA) and multiple regression tests were performed. The results revealed that half of the students had a poor level of sleep quality and most of them were considered unhealthy. The Pearson correlation co-efficient indicated a significant association between the excessive use of mobile phones and the total score of general health and the quality of sleep. In addition, the results of the multiple regression showed that the excessive use of mobile phones has a significant relationship between each of the four subscales of general health and the quality of sleep. Furthermore, the results of the multivariate regression indicated that the quality of sleep has a simultaneous effect on each of the four scales of the general health. Overall, a simultaneous study of the effects of the mobile phones on the quality of sleep and the general health could be considered as a trigger to employ some intervention programs to improve their general health status, quality of sleep and consequently educational performance.

Background: Chitosan is a polysaccharide biopolymer derived from chitin. It not only stimulates growth and increases the crop yields but also alleviates the harmful effect of abiotic stress on plant growth. The objective of this study was to investigate the effects of chitosan on germination and growth of ajowan (Carum copticum) under salt stress. This study was conducted in a laboratory and greenhouse. Material and Methods: In the first experiment seed germination of ajowan monitored under seed pre-treated by soaking in chitosan solutions of 0, 0.01%, 0.05%, 0.1%, 0.2% and 0.5% for 3 h. In second experiment, seeds soaked in chitosan solutions (0 and 0.2%) and sown in pots at different salinity levels (0, 4, 8 and 12 dS/m). Results: Results indicated that all of chitosan concentrations increased germination percentage, germination rate, seedling vigour index, length and dry weight of hypocotyl and radicle compared to control although, 0.2% chitosan concentration was more effective than other treatments. Salinity caused a significant reduction in germination percentage, shoot length, root length, shoot and root dry weight and relative water content, while chitosan adjusted the salt toxicity. Conclusions: It is concluded that chitosan would be able to stimulate germination and growth of ajowan. It is also resulted that soaking ajowan seeds with chitosan, may alleviate the inhibitory effect of salt stress on the plant growth.Mahdavi B, Rahimi A (2013) Seed priming with chitosan improves the germination and growth performance of ajowan (Carum copticum) under salt stress. Eurasia J Biosci 7: 69-76.http://dx.Giriş: Kitozan, kitinden elde edilen polisakkarit bir biyopolimerdir. Hem büyümeyi uyarmakta ve ürün verimini artırmakta hem de bitki büyümesi esnasında abiyotik streslerin zararlı etkisinin azaltılmasını sağlamaktadır. Bu çalışmanın amacı; kitozanın, tuz stresi altında ajowan (Carum copticum)'ın çimlenme ve büyümesi üzerine etkilerini araştırmaktır. Bu çalışma, laboratuvar ve serada gerçekleştirilmiştir. Materyal ve Metot: İlk deneyde, ajowan tohumunun çimlenmesi, tohumların %0, 0.01, %0.05, %0.1, %0.2 ve %0.5'lik kitozan çözeltilerinde 3 saat bekletilmesi ile gözlemlendi. İkinci deneyde, kitozan çözeltilerinde (0 ve %0.2) bekletilen tohumlar farklı tuzluluk seviyelerindeki (0, 4, 8 ve 12 dS/m) saksılara ekildi. Bulgular: Sonuçlar, %0.2'lik kitozan konsantrasyonunun diğer uygulamalardan daha etkili olmasıyla birlikte, kontrole oranla bütün kitozan konsantrasyonlarının çimlenme yüzdesi, çimlenme oranı, tohum canlılık indeksi, hipokotil ve radikula uzunluğu ve kuru ağırlığını artırdığını gösterdi. Tuzluluk; çimlenme yüzdesi, fide uzunluğu, kök uzunluğu, fide ve kök kuru ağırlık ve nispi su içeriğinde önemli bir azalmaya sebep olurken, kitozan tuz toksisitesini düzeltti. Sonuçlar: Kitozanın, ajowanın çimlenme ve büyümesini uyarabileceği sonucuna varıldı. Ayrıca, ajowan tohumlarının kitozan çözeltisinde bekletilmesinin, tuz stresinin bitki büyümesi üzerindeki inhibitör etkisini hafifletebileceği sonucuna varıldı.

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