Mineralogy of the deep lower mantle in the presence of H2O

Understanding the mineralogy of the Earth''s interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle (DLM, 1800–2890 km in depth) and observed surprising mineralogical transformations in the presence of water. Ferropericlase, (Mg, Fe)O, which is the most abundant oxide mineral in Earth, reacts with H₂O to form a previously unknown (Mg, Fe)O₂H_x (x ≤ 1) phase. The (Mg, Fe)O₂H_x has a pyrite structure and it coexists with the dominant silicate phases, bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for (Mg_0.6Fe_0.4)O or beyond 2300 km for (Mg_0.7Fe_0.3)O. The (Mg, Fe)O₂H_x is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences (Mg²⁺, Fe³⁺ and H⁺). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DLM and an internal source for modulating oxygen in the atmosphere.     

On-the-Job Training: Prescriptions and Practice

This article discusses the status of workplace training in the United States, describes a model of how to conduct effective on-the-job training, and presents the results of a questionnaire based on a model designed to assess on-the-job training practices aboard Navy ships. The model views the on-the-job trainer as a coach who guides the trainee through a task using three steps: 1) assessment, 2) training, and 3) evaluation. The questionnaire was sent to over 5,000 shipboard supervisors; 2,321 responded. Results indicate that nearly 50% of the Navy supervisors who responded are not as effective as they could be. The implications of these findings for the civilian workplace are discussed.     

Effects of transition from elementary school to junior high school on early adolescents' self-esteem and perceived competence

Early adolescents' self-esteem and perceived competence in the cognitive, social, and physical domains were examined across the transition from elementary school to junior high school. Self-esteem and perceived social and physical competence were either stable or increased for most children. Cognitive competence was unchanged. It was concluded that, in general, early adolescents' perceptions of self-esteem and competence are not adversely affected by the transition.     

The relationship between metacognition and intelligence in normal adolescents: Some tentative but surprising findings

This study explored the relationship between metacognition and intelligence in a group of normal adolescents. The relationship has strong theoretical support in current conceptions of intelligence. For the purposes of this study metacognition was assessed across three different cognitive problem sets. Correlational analyses indicated a nonsignificant relationship between intelligence and metacognition. These results suggest that tests of metacognition and intelligence may tap unrelated aspects of cognition and that additional research will be required to understand the relationship between these two constructs.     

Social media and the university decision. Do prospective students really care?

In the world of social media marketing, colleges and universities can benefit from enhanced understanding of how prospective students use social media. Due to the ever-evolving nature of social media use, there are gaps in the current research regarding how students use social media to aid in their matriculation decision-making. Using survey data from current university students across the U.S. (n?=?364) and one-on-one interviews (n?=?12) with students at a small liberal arts college, the authors address conflicting information where students report both using and not using social media to narrow their search and make their matriculation decision. The findings suggest that while students may not report visiting social media sites or may report that social media does not impact their matriculation decision when asked in a survey, in interview settings the vast majority of students reported using social media platforms to learn more about higher education schools under consideration. By exploring which platforms students use and the selection of platforms for specific use cases, the authors provide suggestions and guidelines for social media managers looking to maximize the effectiveness of their social media recruiting strategies and campaigns.     

Youth on the street: Abuse and neglect in the eighties

This paper discusses the findings of a study of runaways and homeless youth who were interviewed on the street the last week of every month on five week nights from late afternoon until 2 a.m. over a period of one year. The data derived from 489 interviews provided some interesting insights. Two distinct groups emerged from the analysis, generating a tentative hypothesis that the true "runners" tend to leave their homes with the intention of not returning and thus their runs are extended; the second group, designated "in and outers," use the run as a temporary coping mechanism. Their runs tend to be impulsive and of short duration. The study found that runaways (in particular the runners) are at great risk of being drawn into illegal activities. Major factors affecting this risk are distance from home and length of time on the run. A significant proportion of the youth interviewed had run from substitute care arrangements, and a disturbing implication emerging from the research is that adolescents in our society suffer from systemic abuse and neglect. One outcome of this piece of research was the opening of a safe house for early runners in January 1987. The operation of the house includes careful compilation of data to further advance understanding of the runaway population and its needs.