Time filter

Source Type

Fairfax, VA, United States

George Mason University is the largest research university in Virginia and is based in Fairfax County, Virginia, United States, south of and adjacent to the city of Fairfax. Additional campuses are located nearby in Arlington County, Prince William County, and Loudoun County. The university's motto is Freedom and Learning.The university was founded as a branch of the University of Virginia in 1957 and became an independent institution in 1972. Today, Mason is recognized for its strong programs in economics, law, creative writing, computer science, and business. In recent years, George Mason faculty have twice won the Nobel Prize in Economics. The university enrolls 33,917 students, making it the largest university by head count in the Commonwealth of Virginia. Wikipedia.

Renshaw K.D.,George Mason University
Journal of Affective Disorders | Year: 2011

Background: Few attempts have been made to integrate the known risk factors for combat-related posttraumatic stress disorder (PTSD) into a comprehensive model. This study investigated relative contributions of combat experiences, post-battle experiences, and perceptions of threat to post-deployment PTSD symptoms, and also examined whether pre-deployment preparedness moderated associations among these variables. Methods: Two hundred seven troops deployed to the Middle East between 2001 and 2008 completed self-report measures. Data were analyzed using path analysis and regressions. A comprehensive model including additive effects, mediation, and moderation was examined. Results: Perceptions of threat mediated the association of combat experiences with PTSD, but not that of post-battle experiences with PTSD. Sense of preparedness for deployment moderated the association of combat experiences with perceived threat, such that troops with low preparedness perceived high levels of threat regardless of combat exposure, whereas troops with high preparedness perceived levels of threat that were correlated with levels of combat. Limitations: Data were cross-sectional, all assessment was retrospective self-report, and the sample was primarily White, male, and married. Conclusions: Combat and post-battle experiences appear linked to PTSD via separate pathways. Thus, PTSD prevention efforts may need to vary based on types of events experienced. Pre-deployment preparation mitigated perceived threat in the context of low combat exposure, but it did not moderate direct associations of risk factors with PTSD symptoms. Thus, pre-deployment training and preparation do not appear sufficient to protect against PTSD. © 2010 Elsevier B.V. Source

Uhen M.D.,George Mason University
Annual Review of Earth and Planetary Sciences | Year: 2010

Whales are first found in the fossil record approximately 52.5 million years ago (Mya) during the early Eocene in Indo-Pakistan. Our knowledge of early and middle Eocene whales has increased dramatically during the past three decades to the point where hypotheses of whale origins can be supported with a great deal of evidence from paleontology, anatomy, stratigraphy, and molecular biology. Fossils also provide preserved evidence of behavior and habitats, allowing the reconstruction of the modes of life of these semiaquatic animals during their transition from land to sea. Modern whales originated from ancient whales at or near the Eocene/Oligocene boundary, approximately 33.7 Mya. During the Oligocene, ancient whales coexisted with early baleen whales and early toothed whales. By the end of the Miocene, most modern families had originated, and most archaic forms had gone extinct. Whale diversity peaked in the late middle Miocene and fell thereafter toward the Recent, yielding our depauperate modern whale fauna. Copyright © 2010 by Annual Reviews. All rights reserved. Source

Ehrlich R.,George Mason University
Astroparticle Physics | Year: 2013

With a recent claim of superluminal neutrinos shown to be in error, 2012 may not be a propitious time to consider the evidence that one or more neutrinos may indeed be tachyons. Nevertheless, there are a growing number of observations that continue to suggest this possibility - albeit with an m 2m < 0 having a much smaller magnitude than was implied by the original OPERA claim. One recently published nonstandard analysis of SN 1987A neutrinos supports a tachyonic mass eigenstate, and here we show how it leads to 3 + 3 mirror neutrino model having an unconventional mass hierarchy. The model incorporates one superluminal active-sterile neutrino pair, and it is testable in numerous ways, including making a surprising prediction about an unpublished aspect of the SN 1987A neutrinos. Additional supporting evidence involving earlier analyses of cosmic rays is summarized to add credence to the tachyonic neutrino hypothesis. © 2012 Elsevier B.V. All rights reserved. Source

Richards P.G.,George Mason University
Journal of Geophysical Research: Space Physics | Year: 2011

This paper reexamines the chemistry of N2 +, NO +, O2 +, and N+ by comparing densities from a photochemical model with data from the Atmosphere Explorer C satellite. These comparisons show that the measurements of N2 +, NO+, O2 +, and N+ density are well modeled with up-to-date reaction rates, solar EUV irradiances, and photoelectron fluxes. In particular, this study has resolved a long-standing problem wherein the previous investigations overestimated the measured N 2 + density by a factor of 2. A new method of determining the important and controversial O+(2D) + N2 reaction rate from the Atmosphere Explorer C data is presented. This reaction rate determination agrees well with the latest laboratory measured reaction rate. Copyright 2011 by the American Geophysical Union. Source

Frankenfeld C.L.,George Mason University
American Journal of Clinical Nutrition | Year: 2011

Background: Equol and O-desmefhylangolensin (ODMA) are products of gut bacterial metabolism of daidzein, a phytochemical found predominantly in soy. Dietary sources of equol from animal products have been identified, which has raised the question of the relative contributions of daidzein intake and gut metabolism to equol and of equol intake from animal products in low-soy-consuming populations. Objective: The objective was to evaluate the contribution of dietary food groups to urinary isoflavone and daidzein metabolite concentrations in a representative sample of US adults. Design: A cross-sectional analysis of dietary and urinary isoflavonoid data from 3115 individuals in the 2001-2002 and 2003-2004 data cycles of the National Nutrition and Health Examination Survey (NHANES) was conducted. Results: Daidzein intake and consumption frequency of grain products and legumes, nuts, and seeds were significant correlates of daidzein, genistein, and ODMA concentrations; and soy legumes were a stronger correlate than were nonsoy legumes. Milk and milk product consumption and daidzein intake, but not legumes, were significant correlates of urinary equol concentrations; milk products were more strongly correlated (P for trend < 0.001) than was daidzein intake (P = 0.011). Conclusions: These results suggest that dietary daidzein and legumes may contribute to urinary daidzein, genistein, and ODMA concentrations in this low-soy-consuming population. These results also suggest that equol concentrations in low-soy-consuming populations may reflect equol intakes from mammalian milk sources and may not reflect the endogenous production of equol from the microbial metabolism of daidzein - an observation not yet documented in the US population. These results support the careful design and interpretation of urinary isoflavonoid excretion studies, particularly bacterial metabolites, in low-soy-consuming populations. © 2011 American Society for Nutrition. Source

Discover hidden collaborations