Around the globe, and in a variety of settings including active and inactive mountain belts, increases in sedimentation rates as well as in grain sizes of sediments were recorded at approximately 2-4 Myr ago, implying increased erosion rates. A change in climate represents the only process that is globally synchronous and can potentially account for the widespread increase in erosion and sedimentation, but no single process-like a lowering of sea levels or expanded glaciation-can explain increases in sedimentation in all environments, encompassing continental margins and interiors, and tropical as well as higher latitudes. We suggest that climate affected erosion mainly by the transition from a period of climate stability, in which landscapes had attained equilibrium configurations, to a time of frequent and abrupt changes in temperature, precipitation and vegetation, which prevented fluvial and glacial systems from establishing equilibrium states.

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The effects of childhood sexual abuse on the development of alcoholism in women were examined by comparing a sample of 45 alcoholic women selected from local treatment agencies and Alcoholics Anonymous groups with a group of 40 nonalcoholic women selected randomly from a household population. Face-to-face interview schedules were administered to both samples. Sexual abuse was defined as any unwanted sexual contact with a person at least five years older than the respondent, or with any family relative, regardless of age difference. Types of sexual contact included both nonphysical contact (e.g., invitations, exposure) and physical contact (e.g., fondling, intercourse). Results showed that alcoholic women were more likely to have experienced sexual abuse, had a greater number of different types of sexual abuse experiences, and endured sexual abuse over a longer period than the comparison group. The presence of any childhood sexual abuse experience was sufficient to discriminate between the alcoholic women and the comparison group, even controlling for demographic variables and the presence of a parent with alcohol-related problems. Although alcoholic women were more likely to report that a parent had alcohol-related problems, relatively few of the sexual abuse incidents were perpetrated by a parent. The data suggest that vulnerabilities to sexual abuse were attributable to environmental or psychological factors in homes in which a parent was reported as having alcohol-related problems.

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The role of adaptive beliefs and attitudes against suicide has not been given adequate attention in the clinical or assessment literature. This article reports on the development and initial psychometric properties of a 32-item self-report inventory, the Reasons for Living Inventory for Adolescents (RFL-A). In Phase 1, we used exploratory and confirmatory factor analyses to identify five correlated factors: Future Optimism, Suicide-Related Concerns, Family Alliance, Peer Acceptance and Support, and Self-Acceptance. In Phase 2, we cross-validated the 5-factor oblique model in a different group of adolescents recruited from two high schools. In addition, we examined evidence for convergent, discriminant, and construct validities. The coefficient alpha indices for the RFL-A total and scales were satisfactory. In Phase 3, we evaluated additional evidence of reliability and validity using samples of high school and psychiatric inpatient adolescents. The results suggest that the RFL-A is a short, reliable, and valid measure that is potentially useful in the assessment of adolescent suicidal behavior.

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Crocodylian teeth are generally conical with little differentiation in shape along the tooth row. The mandible is incapable of any fore-aft movement, and feeding typically involves little or no intraoral processing. Complex, multi-cusped, mammal-like teeth differentiated along the tooth row have been found in a Cretaceous crocodylian from Malawi. The morphology of the teeth and mandible indicates that food items were processed by back-to-front (proal) movement of the mandible, unlike living crocodylians but as in some mammals and Sphenodon (the tuatara).