Numerical Uncertainty Quantification for Radiation Analysis Tools

Recently a new emphasis has been placed on engineering applications of space radiation analyses and thus a systematic effort of Verification, Validation and Uncertainty Quantification (VV&UQ) of the tools commonly used for radiation analysis for vehicle design and mission planning has begun. There are two sources of uncertainty in geometric discretization addressed in this paper that need to be quantified in order to understand the total uncertainty in estimating space radiation exposures. One source of uncertainty is in ray tracing, as the number of rays increase the associated uncertainty decreases, but the computational expense increases. Thus, a cost benefit analysis optimizing computational time versus uncertainty is needed and is addressed in this paper. The second source of uncertainty results from the interpolation over the dose vs. depth curves that is needed to determine the radiation exposure. The question, then, is what is the number of thicknesses that is needed to get an accurate result. So convergence testing is performed to quantify the uncertainty associated with interpolating over different shield thickness spatial grids

Adoption and Use of a Computer-Mediated Communication System by Contact North Site Coordinators

This paper describes some of the factors underlying successful use of the CoSy computer-mediated communication system in the Ontario Govern-ment's Contact North/Contact Nord Distance Education Project by 11 women who, in a relatively short period of time, acquired sufficient competence with CoSy to make conferencing an integral part of their role as community educators. Their very positive response to the technological demands of the job runs counter to expectations developed in much of the literature on women, work, and technology. For the most part, previous research has characterized women's relationship with technology as antagonistic. Our description of the process of adoption and use of CoSy at Contact North provides an alternative understanding of the initial relationship between characteristics of the individual and the machine. The reasons underlying resistance to technological change are an important source of knowledge; but equally important is the basis for enthusiasm that can greet new technological conditions of work. Rather than representing barriers to be overcome or problems to be surmounted, computer conferencing systems can offer a congenial setting for establishing the technical competence and positive attitudes that lead to adoption and use decisions

Martha Smith, Stephen Edds, and Amy Anderson in a Joint Junior Recital

This is the program for the joint voice recital of soprano Martha Jane Smith, bass-baritone Stephen Edds, and soprano Amy Anderson. Pianist Cynthia McDonnough assisted Smith; pianist Sylvia McDonnough assisted Edds; and pianist Cynthia McDonnough assisted Anderson. The recital took place on February 27, 1978, in the Mabee Fine Arts Center Recital Hall

Evolving a Network of Networks: The Experience of Partnerships in the National Digital Information Infrastructure and Preservation Program

The National Digital Information Infrastructure and Preservation Program (NDIIPP) was initiated in December 2000 when the U.S. Congress authorized the Library of Congress to work with a broad range of institutions to develop a national strategy for the preservation of at-risk digital content. Guided by a strategy of collaboration and iteration, the Library of Congress began the formation of a national network of partners dedicated to collecting and preserving important born-digital information. Over the last six years, the Library and its partners have been engaged in learning through action that has resulted in an evolving understanding of the most appropriate roles and functions for a national network of diverse stakeholders. The emerging network is complex and inclusive of a variety of stakeholders; content producers, content stewards and service providers from the public and private sectors. Lessons learned indicate that interoperability is a challenge in all aspects of collaborative work

Subtypes of Attentional Bias within Social Anxiety Disorder: Evaluating Changes following Cognitive Behavioral Therapy

Prominent theories of social anxiety disorder (SAD) describe the role of attentional bias in the disorder\u27s etiology and maintenance; some models implicate bias toward social threats (e.g., Rapee & Heimberg, 1997) and others implicate bias to avoid them (e.g., Clark & Wells, 1995). The present investigation examined: 1) whether a clinical sample of individuals with SAD comprises two distinct groups based on attention bias for social threat (vigilant, avoidant), and 2) group-specific changes in attention bias following cognitive behavioral therapy (CBT) for SAD. Consistent with predictions, results yielded evidence of two pre-treatment groups (vigilant and avoidant). After eight weeks of treatment, the direction of change in attention bias differed between groups, such that the vigilant group became less vigilant, and the avoidant group became less avoidant, with the avoidant group showing a significant change in attention bias from pre- to post-treatment. These findings provide preliminary support for the hypothesis that SAD comprises subgroups with both threat vigilant and threat avoidant attentional styles and change in different directions following treatment. Implications for how individuals who exhibit one attentional bias or the other may differentially respond to treatment are discussed

Food Deserts

A food desert is a geographical area in which there is not easy access to fresh, healthy, and affordable food.https://digitalcommons.cedarville.edu/public_health_posters/1013/thumbnail.jp

A Comparison of X-ray and Radio Emission from the Supernova Remnant Cassiopeia A

We compare the radio and soft X-ray brightness as a function of position within the young supernova remnant Cassiopeia A. A moderately strong correlation (r = 0.7) was found between the X-ray emission (corrected for interstellar absorption) and radio emission, showing that the thermal and relativistic plasmas occupy the same volumes and are regulated by common underlying parameters. The logarithmic slope of the relationship, ln(Sx-ray) = 1.2 x Sradio + ln(k) implies that the variations in brightness are primarily due to path length differences. The X-ray and radio emissivities are both high in the same general locations, but their more detailed relationship is poorly constrained and probably shows significant scatter. The strongest radio and X-ray absorption is found at the western boundary of Cas A. Based on the properties of Cas A and the absorbing molecular cloud, we argue that they are physically interacting. We also compare ASCA derived column densities with 21 cm H I and 18 cm OH optical depths in the direction of Cas A, in order to provide an independent estimate of ISM properties. We derive an average value for the H I spin temperature of about 40 K and measure the ratio of OH to molecular hydrogen to be nominally larger than previous estimates. Keywords: Cas A, Cassiopeia A, interstellar medium, molecular clouds, radio astronomy, supernova remnants, X-ray astronomyComment: To appear in Vol. 446 of The Astrophysical Journal on Aug. 1, 1996; 10 pages with 5 embedded figures; replaced because of updated reference

Mthfs is an Essential Gene in Mice and a Component of the Purinosome

Tetrahydrofolates (THF) are a family of cofactors that function as one-carbon donors in folate-dependent one-carbon metabolism, a metabolic network required for the de novo synthesis of purines, thymidylate, and for the remethylation of homocysteine to methionine in the cytoplasm. 5-FormylTHF is not a cofactor in one-carbon metabolism, but serves as a storage form of THF cofactors. 5-formylTHF is mobilized back into the THF cofactor pool by methenyltetrahydrofolate synthetase (MTHFS), which catalyzes the irreversible and ATP-dependent conversion 5-formyltetrahydrofolate to 5,10-methenyltetrahydrofolate. Mthfs is not an essential gene in Arabidopsis, but MTHFS expression is elevated in animal tumors, enhances de novo purine synthesis, confers partial resistance to antifolate purine synthesis inhibitors and increases rates of folate catabolism in mammalian cell cultures. However, the mechanisms underlying these effects of MTHFS expression have yet to be established. The purpose of this study was to investigate the role and essentiality of MTHFS in mice. Mthfs was disrupted through the insertion of a gene trap vector between exons 1 and 2. Mthfsgt/+ mice were fertile and viable. No Mthfsgt/gt embryos were recovered from Mthfsgt/+ intercrosses, indicating Mthfs is an essential gene in mice. Tissue MTHFS protein levels are decreased in both Mthfsgt/+ and Mthfs+/+ mice placed on a folate and choline deficient diet, and mouse embryonic fibroblasts from Mthfsgt/+ embryos exhibit decreased capacity for de novo purine synthesis without impairment in de novo thymidylate synthesis. MTHFS was shown to co-localize with two enzymes of the de novo purine synthesis pathway in HeLa cells in a cell cycle-dependent manner, and to be modified by the small ubiquitin-like modifier (SUMO) protein. Mutation of the consensus SUMO modification sites on MTHFS eliminated co-localization of MTHFS with the de novo purine biosynthesis pathway under purine-deficient conditions. The results from this study indicate that MTHFS enhances purine biosynthesis by delivering 10-formylTHF to the purinosome in a SUMO-dependent fashion