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The effect of Mn and Fe dopants on the electromechanical and electrochemical properties of 0.88[Bi0.5Na0.5]TiO3–0.08[Bi0.5K0.5]TiO3–0.04[Bi0.5Li0.5]TiO3 piezoceramic is investigated with particular emphasis on complex impedance in the temperature range from 450 to 600 °C. The impedance spectra have been simulated with equivalent circuits in order to extract bulk and grain boundary characteristics and to determine activation energies of conduction. Mn and Fe dopants considerably enhance the mechanical quality factor and decrease the dielectric loss compared to the undoped composition. Mn doping leads to dramatically higher resistivity in the bulk and a modest increase in the bulk activation energy. On the other hand, conductivity increases dramatically via Fe doping with a significant lowering of activation energy in the bulk and corresponding raising of the activation energy at grain boundaries in comparison to Mn-doped and undoped ceramic. The bulk conductivity of Fe-doped piezoceramic reaches as high as 0.01 S cm−1 at 600 °C. [ABSTRACT FROM AUTHOR]

This article presents preliminary findings of a randomized HIV prevention study in Trinidad and Tobago in the Caribbean. The study centers on a family HIV workshop aimed at strengthening parenting skills that are empirically linked to reducing adolescent HIV exposure and other sexual risks. These skills include parental monitoring; educating youth about HIV, sex, and other sexually transmitted infections (STI's); and discussing cultural and interpersonal pressures to have sex. Participants include 180 primary caregivers and their 12--14-year-old adolescents randomized to either the Trinidad and Tobago family HIV Workshop (N = 92) or a general workshop (N = 88). Intervention and control group participants completed pretest and posttest measures on parenting and HIV risk outcomes. Compared to controls, intervention parents reported improvements in HIV knowledge (d = 0.79); attitudes toward AIDS (d = 0.42); general communication with adolescents (d = 0.94); conversations with adolescents about sex (d = 0.95); conversations about sexual risks and values (d = 0.43); monitoring of adolescents (d = 0.34); conflicts with adolescents (d = 0.30); and intensity of daily parenting hassles (d = 0.35). Intervention and control parents did not differ in behavioral control, use of positive parenting techniques, and expansion of support networks. Implications for addressing rising HIV risks among young people in Trinidad and Tobago and the Caribbean are discussed.

Grafton Middle School in York County, Virginia has consistently met state accreditation criteria and has repeatedly met adequate yearly progress markers. Rather than abandoning previous work to improve curriculum and instruction by fully adopting the newest reform that improves student achievement, the authors decided to complement past efforts with classroom-based assessment to help teachers more accurately determine the degree of student learning in the classroom. In this article, the authors describe how they implemented classroom-based assessments at Grafton Middle School. (Contains 1 figure.)

Brain is the source of all human thoughts, feelings and emotions. Now the mysteries of the human brain are rapidly being elucidated by neuroscience research. For more than 150 years, neuroscience has held that most of the brain's functionality develops during critical periods in early childhood and that once past these critical periods, the window of opportunity for brain modification slams shut. However, today, after decades of research, this view of the brain as analogous to a hard-wired computer in favor of the concept that the brain is a continuously modifiable "plastic" organ throughout life was abandoned. This realization provides new opportunities for researchers to explore and develop a more complete understanding of human brain development and cognition and, most importantly to educators, to create neuroscience-informed instructional strategies that enhance the brain's capacity to modify itself through learning, known as neuroplasticity. Furthermore, the authors discuss lthe anguage-to-literacy link, which compels them to explore the components of spoken language, the organization of these components in the brain and the links between them and reading so they can understand how the brain learns to read.

We propose a conceptual framework to illustrate that when three conditions hold, institutional investors moderate a positive relation between corporate financial performance and corporate environmental performance. We explore heterogeneities across institution types to demonstrate the importance of each condition. The moderating effect works through the channels of expert consulting and effective monitoring. Our results have important policy and practical implications given the global trend of ownership concentration in institutional investors and the projection that by 2025, one out of three dollars under professional management will be invested in corporate social responsibility assets. [ABSTRACT FROM AUTHOR]