Behavior and emotional problems among Jamaican children and adolescents: an epidemiological survey of parent, teacher, and self-reports for ages 6–18 years

The study compared general population samples of Jamaican children ages 6–18 years, via Jamaican versions of the Child Behavior Checklist (CBCL) parent-, teacher-, and self-report forms. Repeated measures ANOVAs with informant as a repeated measures factor, assessed base-rate problem score differences according to children’s area of residence (i.e., urban vs rural), gender, and age. No between subjects residence effects emerged for total problem score. However, adolescents self-reported higher total problem scores compared to the ratings they received from their parents and teachers. No gender total problem score effects emerged for any of the three informants, but girls received higher internalizing, and Somatic Complaints scores. Similar total problem scores across genders, and the high ratio of boys to girls in clinic samples suggest that Jamaican girls may not be receiving adequate services. Age X within subjects interactions revealed higher teacher reported problem scores for young adolescents, reflecting possible developmental changes within the classroom context and teachers’ low thresholds toward these problems. The d statistic revealed base rate syndrome, internalizing, externalizing, and total problem score differences in most Jamaican vs US sub-samples. In addition to the non-CBCL problems observed in earlier studies, these findings clearly indicate a need to ascertain syndrome structure and other psychometric properties of the Jamaican instruments.     

The slow neutron-induced radioactivities of nuclear explosions

The slow neutron-induced radioactivities of nuclear explosions have been evaluated for infinite media of filtered Schuylkill water and the earth's crust. The magnitudes of these effects are compared with the activity of the fission fragments, and the conditions under which they may be of importance are considered.It has been assumed that a gram-molecule of neutrons is liberated in the blast.     

Theory of the halftone process. II. The diffraction theory-calculation of the light distribution

An approximate method of calculating the light distribution in the dots formed behind a halftone screen from the Fresnel diffraction theory is described, and in a typical case, the distribution is found to check closely with that determined experimentally, being very different from that calculated from geometrical optics.