Application of induction heating to high temperature fatigue testing

Accelerated activity in the development of hypersonic aircraft and spacecraft has created new problems of materials testing. Testing equipment must be capable of simulating higher temperatures as well as severe thermal cycling superimposed upon the cyclic application of stress. Among the materials under study requiring this testing equipment are the heavy refractory metals such as tungsten and molybdenum, which are capable to operating at very high temperatures while maintaining strength

The Occurrence of Rhopilema verrilli (Cnidaria: Scyphozoa: Rhizostomeae) on Galveston Island, Texas, and a Discussion on Its Distribution in U.S. Waters

A specimen of the rhizostome scyphomedusa Rhopilema verrilli was stranded on the beach at Galveston Island, Texas, in the spring of 1985. Two young specimens have since been collected In the marshes on the north side of Galveston bordering West Galveston Bay. This species Is relatively rare throughout most of Its range and has only been reported once before in the western Gulf of Mexico. Seasonal and geographic distributions from literature records are discussed in relation to temperature, salinity, currents, and life history. Occurrences along the U.S. East Coast Indicate progressively later seasonal appearances and decreased abundances from Georgia to New England. Occurrences In the Gulf of Mexico are almost all limited to the Mississippi Sound area. Collection records suggest that R. verrilli has two centers of distribution, one in southern U.S. East Coast waters and one in the northeastern Gulf of Mexico, and that occurrences outside these centers are due to transport by currents. We believe that R. verrilli\u27s apparent rarity in the western Gulf of Mexico results primarily from a combination of wind-driven current patterns, timing of volume of Mississippi-Aatchafalaya River discharge, and temperature-salinlty tolerances of the species acting against transport into, and survival in, the western Gulf

Generating Bijections between HOAS and the Natural Numbers

A provably correct bijection between higher-order abstract syntax (HOAS) and the natural numbers enables one to define a "not equals" relationship between terms and also to have an adequate encoding of sets of terms, and maps from one term family to another. Sets and maps are useful in many situations and are preferably provided in a library of some sort. I have released a map and set library for use with Twelf which can be used with any type for which a bijection to the natural numbers exists. Since creating such bijections is tedious and error-prone, I have created a "bijection generator" that generates such bijections automatically together with proofs of correctness, all in the context of Twelf.Comment: In Proceedings LFMTP 2010, arXiv:1009.218

The Sirius Passet Lagerstätte of North Greenland—A geochemical window on early Cambrian low‐oxygen environments and ecosystems

The early Cambrian Sirius Passet fauna of northernmost Greenland (Cambrian Series 2, Stage 3) contains exceptionally preserved soft tissues that provide an important window to early animal evolution, while the surrounding sediment holds critical data on the palaeodepositional water‐column chemistry. The present study combines palaeontological data with a multiproxy geochemical approach based on samples collected in situ at high stratigraphic resolution from Sirius Passet. After careful consideration of chemical alterations during burial, our results demonstrate that fossil preservation and biodiversity show significant correlation with iron enrichments (FeHR/FeT), trace metal behaviour (V/Al), and changes in nitrogen cycling (δ15N). These data, together with Mo/Al and the preservation of organic carbon (TOC), are consistent with a water column that was transiently low in oxygen concentration, or even intermittently anoxic. When compared with the biogeochemical characteristics of modern oxygen minimum zones (OMZs), geochemical and palaeontological data collectively suggest that oxygen concentrations as low as 0.2–0.4 ml/L restricted bioturbation but not the development of a largely nektobenthic community of predators and scavengers. We envisage for the Sirius Passet biota a depositional setting where anoxic water column conditions developed and passed over the depositional site, possibly in association with sea‐level change, and where this early Cambrian biota was established in conditions with very low oxygen

Community-Based After-School Inclusive Programs for Low-Income Minority Youth and Their Families: the Disability Specialist Approach

Intervention for helping community based after-school programs become more responsive to youth with disabilities and their families is presented in this manuscript. The Disability Specialist intervention utilized a variety of approaches, including: a) increasing awareness of disabilities and services by providing learning opportunity sessions for families and staff, and outreach activities to youth through interactive theater; b) developing in house “disability specialists” to offer ongoing leadership and technical expertise for after-school programs and their community centers; c) developing a network of technical consultants in order to connect families and after-school programs to specialized community resources; d) providing financial assistance to enable community center staff to allocate time to outreach activities; and e) providing families with support in educational advocacy efforts by partnering with a local parent mentoring program. The success of the project depended upon building partnerships with families, community centers, human service agencies, schools, and local funding sources