Analysis and test of a 16-foot radial rib reflector developmental model

Analytical and experimental modal tests were performed to determine the vibrational characteristics of a 16-foot diameter radial rib reflector model. Single rib analyses and experimental tests provided preliminary information relating to the reflector. A finite element model predicted mode shapes and frequencies of the reflector. The analyses correlated well with the experimental tests, verifying the modeling method used. The results indicate that five related, characteristic mode shapes form a group. The frequencies of the modes are determined by the relative phase of the radial ribs

Financial Development, Bank Ownership, and Growth. Or, Does Quantity Imply Quality?

In 1980, India nationalized its large private banks. This induced different bank ownership patterns across different towns, allowing credible identification of the effects of bank ownership on financial development, lending rates, and the quality of intermediation, as well as employment and investment. Credit markets with nationalized banks experienced faster credit growth during a period of financial repression. Nationalization led to lower interest rates and lower quality intermediation, and may have slowed employment gains in trade and services. Development lending goals were met, but these had no impact on the real economy.

The Promise and Challenge of Mentoring High-Risk Youth: Findings from the National Faith-Based Initiative

This report, the third derived from research out of the National Faith-Based Initiative (NFBI), examines how faith-based organizations designed and implemented mentoring programs for high-risk youth. Focusing on four NFBI sites (in the Bronx and Brooklyn, NY; Baton Rouge, LA; and Philadelphia, PA), the report takes up three key questions: How were the best practices of community-based mentoring programs adapted to address the specific needs of faith-based mentors and high-risk youth? How did the organizations draw on the faith community to recruit volunteers, and who came forward? And finally, how successful were the mentoring relationshipshow long did they last and what potential did they show

Teaching in the Middle Grades Today: Examining Teachers’ Beliefs About Middle Grades Teaching

Since the beginning of the middle school movement in the mid-1960s, middle level advocates have called for a school experience for young adolescents grounded in adolescent development that engages students in meaningful learning (Eichhorn, 1966; Alexander & Williams, 1965). The aim of this exploratory multi-case study was to understand middle level teachers’ beliefs about middle level instruction in the current educational environment. To gain this understanding, researchers asked ten current middle grades teachers with varying levels of experience to discuss their beliefs regarding their primary purpose as a middle grades teacher, the current status of middle level teaching, their best and worst instructional lessons, and their perceived barriers to teaching at the middle level. The teachers described the role of teaching in the middle grades as challenging and stressful, but of great importance. In general, they described instruction that included discovery, student engagement, and relevance in an effort to address students’ academic development. There was minimal mention of the non-academic aspects of adolescent development. Finally, teachers viewed curriculum restrictions, students’ attitudes toward learning, difficulty with differentiation, and lack of technology as significant barriers to their success in the classroom

The Status of Middle Schools in the Southeastern United States: Perceptions and Implementation of the Middle School Model

For more than 100 years, education communities have debated how best to educate the young adolescent. Proponents of both the junior high school model and the current middle school model have advocated for a specialized approach to educating adolescents that emphasizes the developmental needs of students. To accomplish this, various organizational structures and instructional approaches are recommended. This survey study examines the perceptions of these middle school practices and the implementation of those practices in middle schools in the Southeastern region of the United States. We note several key trends in our results and highlight key differences in perception of importance and implementation of middle school components and strategies compared to the most recent large scale survey administered by McEwin and Greene (2011)

Understanding Current Signals Induced by Drifting Electrons

Consider an electron drifting in a gas toward a collection electrode. A common misconception is that the electron produces a detectable signal only upon arrival at the electrode. In fact, the situation is quite the opposite. The electron induces a detectable current in the electrode as soon as it starts moving through the gas. This induced current vanishes when the electron arrives at the plate. To illustrate this phenomenon experimentally, we use a gas-filled parallel plate ionization chamber and a collimated $^{241}$Am alpha source, which produces a track of a fixed number of ionization electrons at a constant distance from the collection electrode. We find that the detected signal from the ionization chamber grows with the electron drift distance, as predicted by the model of charge induction, and in conflict with the idea that electrons are detectable upon arrival at the collection plate.Comment: 21 pages, 12 figure

Leaf Beetles of the Cayman Islands (Coleoptera: Chrysomelidae)

Data are presented for 29 chrysomelid species (Coleoptera: Chrysomelidae) occurring in the Cayman Islands, West Indies, 26 of these not having been reported from these islands previously. Altica occidentalis Suffrian is removed from the genus Lysathia Bechyné and reinstated in Altica Geoffroy. Chaetocnema perplexa Blake is synonymized with Chaetocnema confinis Crotch, new synonymy. Omophoita cyanipennis octomaculata (Crotch) is synonymized with Omophoita cyanipennis (Fabricius), new synonymy. The following nine species are named and described: Apraea luciae, Apraea priscilae, Cryptocephalus catharinae, Cryptocephalus kirki, Cryptocephalus paulotigrinus, Longitarsus alisonae, Megistops adiae, Nyctiplanctus bifasciatus, Syphrea thurstonae, all are new species. Taxonomic notes and a key to species, as well as information on plant associations and extralimital distribution, are also provided