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Fredericksburg, VA, United States

The University of Mary Washington is a public university in Virginia that focuses on undergraduate education in the liberal arts. The core of its main campus of roughly 4,000 mostly residential students in Fredericksburg, Virginia is the College of Arts and science, which offers degrees in various liberal arts disciplines. A College of Education and a College of Business offer advanced degrees. Around 450 students are enrolled in the University's graduate programs. Wikipedia.

Bonds E.,University of Mary Washington
Environmental Politics | Year: 2016

During the Iraq and Afghanistan wars, the US Department of Defense burned the majority of its solid waste in open-air pits or trenches, producing large amounts of potentially hazardous emissions. While journalists have covered stories of US service members who link their illnesses to these fumes, they have almost entirely ignored potential civilian impacts. However, satellite images demonstrate that pollution from open-air trash burning on US bases could not have impacted US personnel without also harming Iraqi and Afghan civilians living near bases, indicating that burn-pit pollution is an important, if unacknowledged, environmental justice issue. Content analysis of news articles shows the extent to which civilian impacts have been left out of mainstream US media reporting on burn-pit pollution. This selective attention is symptomatic of the way military violence is legitimated, which involves a complicit news media that typically overlooks the humanitarian impacts of war. © 2015 Taylor & Francis. Source

Lee H.-C.,Ajou University | Lee J.,University of Mary Washington
Communications in Computational Physics | Year: 2013

In an interdisciplinary field on mathematics and physics, we examine a physical problem, fluid flow in porous media, which is represented by a stochastic partial differential equation (SPDE). We first give a priori error estimates for the solutions to an optimization problem constrained by the physical model under lower regularity assumptions than the literature. We then use the concept of Galerkin finite element methods to establish a new numerical algorithm to give approximations for our stochastic optimal physical problem. Finally, we develop original computer programs based on the algorithm and use several numerical examples of various situations to see how well our solver works by comparing its outputs to the priori error estimates. © 2013 Global-Science Press. Source

Pope I.C.,Purdue University | Odhiambo B.K.,University of Mary Washington
Environmental Monitoring and Assessment | Year: 2014

Anthropogenic forces that alter the physical landscape are known to cause significant soil erosion, which has negative impact on surface water bodies, such as rivers, lakes/reservoirs, and coastal zones, and thus sediment control has become one of the central aspects of catchment management planning. The revised universal soil loss equation empirical model, erosion pins, and isotopic sediment core analyses were used to evaluate watershed erosion, stream bank erosion, and reservoir sediment accumulation rates for Ni Reservoir, in central Virginia. Land-use and land cover seems to be dominant control in watershed soil erosion, with barren land and human-disturbed areas contributing the most sediment, and forest and herbaceous areas contributing the least. Results show a 7 % increase in human development from 2001 (14 %) to 2009 (21.6 %), corresponding to an increase in soil loss of 0.82 Mg ha-1 year -1 in the same time period. 210Pb-based sediment accumulation rates at three locations in Ni Reservoir were 1.020, 0.364, and 0.543 g cm-2 year-1 respectively, indicating that sediment accumulation and distribution in the reservoir is influenced by reservoir configuration and significant contributions from bedload. All three locations indicate an increase in modern sediment accumulation rates. Erosion pin results show variability in stream bank erosion with values ranging from 4.7 to 11.3 cm year-1. These results indicate that urban growth and the decline in vegetative cover has increased sediment fluxes from the watershed and poses a significant threat to the long-term sustainability of the Ni Reservoir as urbanization continues to increase. © 2013 Springer Science+Business Media. Source

Sharpless C.M.,University of Mary Washington | Blough N.V.,University of Maryland University College
Environmental Sciences: Processes and Impacts | Year: 2014

Absorption of sunlight by chromophoric dissolved natural organic matter (CDOM) is environmentally significant because it controls photic zone depth and causes photochemistry that affects elemental cycling and contaminant fate. Both the optics (absorbance and fluorescence) and photochemistry of CDOM display unusual properties that cannot easily be ascribed to a superposition of individual chromophores. These include (i) broad, unstructured absorbance that decreases monotonically well into the visible and near IR, (ii) fluorescence emission spectra that all fall into a single envelope regardless of the excitation wavelength, and (iii) photobleaching and photochemical quantum yields that decrease monotonically with increasing wavelength. In contrast to a simple superposition model, these phenomena and others can be reasonably well explained by a physical model in which charge-transfer interactions between electron donating and accepting chromophores within the CDOM control the optical and photophysical properties. This review summarizes current understanding of the processes underlying CDOM photophysics and photochemistry as well as their physical basis. This journal is © the Partner Organisations 2014. Source

Dalrymple R.M.,University of Wisconsin - Madison | Carfagno A.K.,SpecPro Environmental Services | Sharpless C.M.,University of Mary Washington
Environmental Science and Technology | Year: 2010

Various aquatic dissolved organic matter (DOM) samples produce singlet oxygen (1O2) and hydrogen peroxide (H2O 2) with quantum yields of 0.59 to 4.5% (1O2 at 365 nm) and 0.017 to 0.053% (H2O2, 300-400 nm integrated). The two species yields have opposite pH dependencies and strong, but opposite, correlations with the E2/E3 ratio (A254 divided by A365). Linear regressions allow prediction of both quantum yields from E2/E3 in natural water samples with errors ranging from 3% to 60%. Experimental evidence and kinetic calculations indicate that less than six percent of the H 2O2 is produced by reaction between 1O 2 and DOM. The inverse relationship between the 1O 2 and H2O2 yields is thus best explained by a model in which precursors to these species are populated competitively. A model is presented, which proposes that important precursors to H2O 2 may be either charge-transfer or triplet states of DOM. © 2010 American Chemical Society. Source

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