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This study aims to prepare oil-modified alkyd resins using a linseed oil/canola oil (LO/CO) blend and waste PET depolymerization product, suitable for environmentally friendly coating applications. Waste PET flakes obtained from grinding post-consumer water bottles were depolymerized by the aminoglycolysis reaction at high pressure. Raw depolymerization product (DP) was used in the synthesis of four components, 50% oil alkyd resins by monoglyceride method. DP has partly replaced the dibasic acid component in the PET-based alkyd formulations. Besides PET-based alkyds, reference alkyds without DP were also synthesized for comparison. Then, the surface coating properties and thermal behaviors of alkyd films were determined. The effect of DP usage and the changing ratios of LO/CO blend on coating properties and thermal behaviors of alkyd films were investigated. In addition, the optimum LO/CO blend ratio which is compatible with alkyd formulation was attempted to be determined. At the end of this study, glossy, soft/medium-hard films were obtained with excellent adhesion, impact strength, and chemical resistance. Thermal resistance and final thermal oxidative degradation temperature increased with adding DP to the alkyd formulation. Using LO/CO blend in the formulations affected oxidation rate and ratio, hence, drying time/degree and oxidative stability of alkyd films.

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RESUMEN

This study assessed the feelings and attitudes of children toward their dentists and their association with oral health. Methods. A questionnaire designed to evaluate the attitudes of children toward dentists and preferences was completed by 200 children and their families. In addition, the children were examined and the World Health Organization (WHO) method was used to obtain dmft and DMFT scores. Results. The mean dmft and DMFT scores were 3.52 ± 2.44 and 1.35 ± 1.29, respectively. Of the children, 92.5% reported that they had visited a dentist before. Of the children who had visited dentists, approximately 71.5% reported that they enjoyed their visits. Of the children, 84% preferred female dentists, 76.5% preferred dentists that wore a colored coat, and 63% preferred a decorated dental clinic over a plain clinic. The mean dmft and DMFT values of children who were afraid of dentists were significantly higher than those of children who were not (P<0.01 and P<0.05, resp.). Conclusion. Children have strong perceptions and preferences regarding the appearance of their dentists and dental clinics. The results of this study might help dentists to improve their delivery of care.

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The authors examined the nature of the relationships between job-specific personality dimensions and psychological well-being for noncommissioned officers (NCOs) in the Turkish Armed Forces (TAF). A job-specific personality inventory, comprising measures of 11 personality dimensions was developed for selection purposes. The inventory was administered to a representative sample of 1,428 NCOs along with a general mental health inventory developed by the authors, which consisted of 6 dimensions of psychological well-being. Exploratory and confirmatory factor analyses suggested existence of a single factor underlying the 6 psychological well-being dimensions, Mental Health, and 2 latent factors underlying the 11 personality dimensions, Military Demeanor and Military Efficacy. The 2 personality constructs explained 91% of the variance in the Mental Health construct. A stepwise regression indicated that beta weights of the personality measures were significant except for military bearing, orderliness, and dependability. Results suggest that job-specific personality attributes were predictive of mental health. Implications of the findings for the selection of NCOs are discussed.

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