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By using a standard questionnaire, the level of dental brushing frequency was assessed among 201 adolescent female middle school students in Tehran. The initial assessment was repeated after 5 months, in order to observe the dynamics in dental health behavior level. Logistic Regression model was used to evaluate the correlation among individuals’ dental health behavior in their social network. A significant correlation on dental brushing habits was detected among groups of friends. This correlation was further spread over the network within the 5 months period. Moreover, it was identified that the average brushing level was improved within the 5 months period. Given that there was a significant correlation between social network’s nodes’ in-degree value, and brushing level, it was suggested that the observed improvement was partially due to more popularity of individuals with better tooth brushing habit. Agent Based Modeling (ABM) was used to demonstrate the dynamics of dental brushing frequency within a sample of friendship network. Two models with static and dynamic assumptions for the network structure were proposed. The model with dynamic network structure successfully described the dynamics of dental health behavior. Based on this model, on average, every 43 weeks a student changes her brushing habit due to learning from her friends. Finally, three training scenarios were tested by these models in order to evaluate their effectiveness. When training more popular students, considerable improvement in total students’ brushing frequency was demonstrated by simulation results.

In this research, preparation of functionalized cellulosic microfibers (FCMFs) was proposed as a beneficial use of cellulosic healthcare wastes for removal of crystal violet from aqueous solutions. The functionalization process was performed using sulfonation reaction by chlorosulfonic acid. The results of scanning electron microscopy revealed a significant deformation in fibrous structure of cellulose as a result of sulfonation process. The functionalization of cellulosic fibers was confirmed by investigation of FTIR spectra of cotton and FCMFs. The charge density of FCMFs was calculated from its sulfur content which was measured by CHNS elemental analyzer. The influence of factors affecting the adsorption process such as pH, salt content, contact time, initial dye concentration and temperature were examined. The adsorption capacity was increased by increasing the salt content and temperature. The equilibrium was achieved after 60 min of mixing. The equilibrium adsorption data were well described by Freundlich, Redlich-Peterson isotherms. The maximum adsorption capacity was found to be 872 mg g -1 . The adsorption kinetic data were well fitted to pseudo-second-order and Elovich kinetic models. Thermodynamic parameters indicated that the adsorption process was spontaneous and endothermic in nature. The residual root-mean-square error (RMSE), average absolute relative error (AARE), cross-correlation coefficient (CCC, R) and chi-square test (χ2) were used to evaluate the fitting of the adsorption isotherms and kinetic models to the experimental results. The saturated adsorbent was regenerated by acid washing (HCl, 1 mol L -1 ) and removal efficiency was decreased slightly in each batch adsorption/regeneration cycle.

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