Detection and Sizing of Ti-Containing Particles in Recreational Waters Using Single Particle ICP-MS

Single particle inductively coupled plasma mass spectrometry (spICP-MS) was used to detect Ti-containing particles in heavily-used bathing areas of a river (Salt River) and five swimming pools. Ti-containing particle concentrations in swimming pools ranged from 2.8?×?10³ to 4.4?×?10³ particles/mL and were an order of magnitude lower than those detected in the Salt River. Measurements from the Salt River showed an 80% increase in Ti-containing particle concentration over baseline concentration during peak recreational activity (at 16:00 h) in the river. Cloud point extraction followed by transmission electron microscopy with energy dispersive X-ray analysis confirmed presence of aggregated TiO₂ particles in river samples, showing morphological similarity to particles present in an over-the-counter sunscreen product. The maximum particle mass concentration detected in a sample from the Salt River (659 ng/L) is only slightly lower than the predicted no effect concentration for TiO₂ to aquatic organisms (<?1 μg/L).     

Motives for Filing a False Allegation of Rape

The list of motives by Kanin (1994) is the most cited list of motives to file a false allegation of rape. Kanin posited that complainants file a false allegation out of revenge, to produce an alibi or to get sympathy. A new list of motives is proposed in which gain is the predominant factor. In the proposed list, complainants file a false allegation out of material gain, emotional gain, or a disturbed mental state. The list can be subdivided into eight different categories: material gain, alibi, revenge, sympathy, attention, a disturbed mental state, relabeling, or regret. To test the validity of the list, a sample of 57 proven false allegations were studied at and provided by the National Unit of the Dutch National Police (NU). The complete files were studied to ensure correct classification by the NU and to identify the motives of the complainants. The results support the overall validity of the list. Complainants were primarily motivated by emotional gain. Most false allegations were used to cover up other behavior such as adultery or skipping school. Some complainants, however, reported more than one motive. A large proportion, 20% of complainants, said that they did not know why they filed a false allegation. The results confirm the complexity of motivations for filing false allegations and the difficulties associated with archival studies. In conclusion, the list of Kanin is, based on the current results, valid but insufficient to explain all the different motives of complainants to file a false allegation.     

Ethnoracial differences in cannabis use among native-born and foreign-born high school students in Ontario

The objective of this study was to examine the association of ethnoracial background and immigrant status to cannabis use among students in Ontario, Canada. Data were derived from the Ontario Student Drug Use and Health Survey, a school-based, province-wide survey of students in Grades 7–12. The survey utilized a stratified two-stage cluster design. Analyses were based on a pooled subsample of 12,527 students in Grades 9–12 during the 2011 and 2013 survey cycles and included adjustments for the complex sample design. Results indicate that youth who were of South Asian or East/Southeast Asian background were at lower odds of cannabis use than those who were White, Black, or mixed-race backgrounds. Youth who were of mixed-race background (i.e., White and another group) were at higher odds of cannabis use than youth who were of White background. The association between ethnoracial background and cannabis use also varied for some foreign-born and native-born youth. These findings suggest that ethnoracial background should be an important consideration in investigations of cannabis use among foreign- relative to native-born youth.