The Myxomycetes of Athens Conty, Ohio

Author Institution: Department of Environmental and Plant BiologyThe goal of this study was to document all reported collections of myxomycetes (slime molds) from Athens County, OH (USA). The compilation of several published and unpublished studies of myxomycete records from Athens County resulted in a total of 52 species. The species were distributed among 6 orders, 9 families, and 25 genera and represent 24% of the myxomycetes known from Ohio and approximately 15% of those recorded for North America. No new collections for the state of Ohio were reported

Searching for Social Capital in U.S. Microenterprise Development Programs

This paper focuses on the claims and efforts of U.S. microenterprise development programs (MDPs) to build social capital among poor and low income entrepreneurs. MDPs offer business training and lending services to individuals operating very small businesses (with five or fewer employees and less than $20,000 in start-up capital). Advocates suggest that MDPs help promote economic development by building social capital defined as networks among small entrepreneurs and between entrepreneurs and their larger community. We begin our paper with a short review of the varied definitions and claims about the role of social capital in promoting civic and economic empowerment. Then, drawing on interviews with practitionersf rom 50 programs, we examine the nature and extent of social capital building in U.S. MDPs. We consider the degree to which our sample MDPs directly promoted networks among clients, and between clients and individuals/organiZationso utside the program. More than half of the programs tried to network clients with each other, but only afew programs focused on building networks between clients and the larger community. From a critical perspective, we discuss more expanded notions of social capital building in poor communities and the barriers to their implementation

Unbalanced Perspective: Two Minnesota Textbooks Examined by an American Indian.

Training Center for Community Programs

Suggested Educational Programs for Teachers and Parents of Urban Indian Youth.

Training Center for Community Programs

An expanded phylogeny of social amoebas (Dictyostelia) shows increasing diversity and new morphological patterns

<p>Abstract</p> <p>Background</p> <p>Social Amoebae or Dictyostelia are eukaryotic microbes with a unique life cycle consisting of both uni- and multicellular stages. They have long fascinated molecular, developmental and evolutionary biologists, and <it>Dictyostelium discoideum </it>is now one of the most widely studied eukaryotic microbial models. The first molecular phylogeny of Dictyostelia included most of the species known at the time and suggested an extremely deep taxon with a molecular depth roughly equivalent to Metazoa. The group was also shown to consist of four major clades, none of which correspond to traditional genera. Potential morphological justification was identified for three of the four major groups, on the basis of which tentative names were assigned.</p> <p>Results</p> <p>Over the past four years, the Mycetozoan Global Biodiversity Survey has identified many new isolates that appear to be new species of Dictyostelia, along with numerous isolates of previously described species. We have determined 18S ribosomal RNA gene sequences for all of these new isolates. Phylogenetic analyses of these data show at least 50 new species, and these arise from throughout the dictyostelid tree breaking up many previously isolated long branches. The resulting tree now shows eight well-supported major groups instead of the original four. The new species also expand the known morphological diversity of the previously established four major groups, violating nearly all previously suggested deep morphological patterns.</p> <p>Conclusions</p> <p>A greatly expanded phylogeny of Dictyostelia now shows even greater morphological plasticity at deep taxonomic levels. In fact, there now seem to be no obvious deep evolutionary trends across the group. However at a finer level, patterns in morphological character evolution are beginning to emerge. These results also suggest that there is a far greater diversity of Dictyostelia yet to be discovered, including novel morphologies.</p

Genetic heterogeneity in wild isolates of cellular slime mold social groups

This study addresses the issues of spatial distribution, dispersal, and genetic heterogeneity in social groups of the cellular slime molds (CSMs). The CSMs are soil amoebae with an unusual life cycle that consists of alternating solitary and social phases. Because the social phase involves division of labor with what appears to be an extreme form of "altruism", the CSMs raise interesting evolutionary questions regarding the origin and maintenance of sociality. Knowledge of the genetic structure of social groups in the wild is necessary for answering these questions. We confirm that CSMs are widespread in undisturbed forest soil from South India. They are dispersed over long distances via the dung of a variety of large mammals. Consistent with this mode of dispersal, most social groups in the two species examined for detailed study, Dictyostelium giganteum and Dictyostelium purpureum, are multi-clonal

Induction Heating Model of Cermet Fuel Element Environmental Test (CFEET)

Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames. Nuclear Thermal Rockets (NTR) are capable of producing a high specific impulse by employing heat produced by a fission reactor to heat and therefore accelerate hydrogen through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of hightemperature hydrogen exposure on fuel elements are limited. The primary concern is the mechanical failure of fuel elements due to large thermal gradients; therefore, highmeltingpoint ceramicsmetallic matrix composites (cermets) are one of the fuels under consideration as part of the Nuclear Cryogenic Propulsion Stage (NCPS) Advance Exploration System (AES) technology project at the Marshall Space Flight Center. The purpose of testing and analytical modeling is to determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures and obtain data to assess the properties of the nonnuclear support materials. The fission process and the resulting heating performance are well known and do not require that active fissile material to be integrated in this testing. A smallscale test bed; Compact Fuel Element Environmental Tester (CFEET), designed to heat fuel element samples via induction heating and expose samples to hydrogen is being developed at MSFC to assist in optimal material and manufacturing process selection without utilizing fissile material. This paper details the analytical approach to help design and optimize the test bed using COMSOL Multiphysics for predicting thermal gradients induced by electromagnetic heating (Induction heating) and Thermal Desktop for radiation calculations

Development and Testing of a Novel Green Propellant Piston Tank

Analytical Mechanics Associates (AMA), in cooperation with NASA Marshall Space Flight Center's (MSFC's) Spacecraft Propulsion Systems Branch, developed and tested a novel propellant tank design that employs an internal piston pressurized with an inert gas to expel propellant to thrusters. During the course of this activity, AMA designed, oversaw fabrication, and delivered to MSFC for testing, a piston propellant tank sized for 3U or larger CubeSats. MSFC conducted liquid expulsion testing using ethylene glycol as a referee fluid to map the tank's performance at different pressures and piston positions. Following the expulsion test campaign, the tank is planned to be integrated into a propulsion system test bed for hot fire tests with a 100mN monopropellant thruster to evaluate the tank's influence on thruster performance when operated in a flight like manner. Described in this paper is a comprehensive summary of how the tanks were designed, built, and tested. The fundamental knowledge gained through the fabrication and testing of these tanks gives evidence that the piston tank design may be scalable to meet the requirements and constraints of other small satellites