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Ramya Kiran B.D.S. James Chapman Ph.D. Marc Tennant Ph.D. Alexander Forrest M.D.Sc. Laurence J. Walsh Ph.D. 《Journal of forensic sciences》2019,64(6):1698-1706
During antemortem and postmortem comparison of dental records of carbonized victims, restorations may be part of such records. The objective of this study was to evaluate the effect of heat on the fluorescence behavior of contemporary tooth‐colored restorative materials and natural tooth structure when subjected to range of temperatures, using illumination with 405 nm wavelength light. A total of 132 human extracted teeth restored with tooth‐colored restorative materials were exposed to heat (200, 500, 900, 1200°C) in an oven for 30 min. Samples were imaged before and after heat treatment. All tooth‐colored restorative materials underwent changes in color and in fluorescence properties, at each of the temperatures used. Resin‐based restorative materials still fluoresced at 200°C, and at 500°C underwent major color changes due to volatilization of resin. Materials containing inorganic fluorophores still fluoresced at 900°C, while at 1200°C, none of the materials tested in this study showed any fluorescence. 相似文献
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Bullying threatens the mental and educational well-being of students. All states have enacted antibullying laws. This study surveyed 634 educators about the implementation of the North Carolina School Violence Prevention Act, which enumerated social classes protected from bullying: race, national origin, gender, socioeconomic status, sexual orientation, gender identity, appearance, and disability. Results showed that local antibullying policies most often included race as a protected class and least often included sexual orientation and gender identity. More educators had been trained on bullying based on race than any other social class. Students were more often informed that bullying based on race was prohibited and were least often informed about prohibitions regarding sexual orientation and gender identity. Reporting, investigating, and remediating bullying was highest for racial bullying, followed by disability bullying, and was lowest for bullying based on sexual orientation and gender identity. 相似文献
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This article looks at the lessons learned in reviewing two long-running international campaigns, one to promote breast-feeding in Ghana, and the other against the use of child labor in the carpet industry in India. In particular, it focuses on understanding the nature of campaigns and what makes them effective. It asserts that campaigns are not linear or mechanistic, but need to be understood as passing through various stages and requiring different kinds of action at different levels and at different times. The variety of work and skills thus required makes it vital that the various organizations involved collaborate with each other. In particular, grassroots mobilization has a role that is often forgotten in bringing about sustained policy change. 相似文献
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