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Newport News, VA, United States

Christopher Newport University, or CNU, is a public liberal arts university located in Newport News, Virginia, United States. CNU is the youngest comprehensive university in the commonwealth of Virginia. The institution is named after Christopher Newport, who was a buccaneer and captain of the Susan Constant, the largest of three ships that carried settlers for the Virginia Company in 1607 on the way to find the settlement at Jamestown in the Virginia Colony, which became the first permanent English settlement in North America. Wikipedia.

Lee T.,Christopher Newport University
Gerontology and Geriatrics Education | Year: 2012

The article theorizes that augmenting traditional humanities course work with documentary video-making can enhance and motivate learning. The English class profiled focused on aging and the lives of elders in an adult daycare center and a retirement community. Students documented elders' stories in video over 15 weeks. The instructor's goal was to use the immediacy of video to challenge and dismantle ageist stereotypes. Documentary video-making is a simple, and enticing, technology that gives students a powerful tool for getting to know elders. Scholarship on classroom uses of digital video-making is discussed, and critical comments from the five reflective essays students wrote during the semester are used to track changes in student perceptions of elders. © 2012 Copyright Taylor and Francis Group, LLC. Source

Lindsay L.,Boston College | Lindsay L.,Christopher Newport University | Broido D.A.,Boston College | Mingo N.,CEA Grenoble | Mingo N.,University of California at Santa Cruz
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We present a theory for the lattice thermal conductivity κL of multilayer graphene (MLG) and graphite, which is based on an exact numerical solution of the Boltzmann equation for phonons. Dominant contributions to κL from out-of-plane or flexural phonons are found, which is consistent with previous findings for single-layer graphene (SLG). However, the interaction between graphene layers in MLG and graphite breaks a selection rule on phonon-phonon scattering, causing their κLs to be much lower than that of SLG. C13 isotopes are shown to be an important scattering mechanism, accounting for an ∼15% additional drop in the κL of these systems. We demonstrate that the κL values converge to that of graphite after only about five layers, a consequence of weak interlayer coupling. These findings are qualitatively consistent with recent measurements of κL for MLG. © 2011 American Physical Society. Source

Badavi F.F.,Christopher Newport University
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2011

Ionizing radiation measurements at low earth orbit (LEO) form the ideal tool for the experimental validation of radiation environmental models, nuclear transport code algorithms and nuclear reaction cross sections. Indeed, prior measurements on the space transportation system (STS; shuttle) have provided vital information impacting both the environmental models and the nuclear transport code development by requiring dynamic models of the LEO environment. Previous studies using computer aided design (CAD) models of the international space station (ISS) have demonstrated that the dosimetric prediction for a spacecraft at LEO requires the description of an environmental model with accurate anisotropic as well as dynamic behavior. This paper describes such a model for the trapped proton. The described model is a component of a suite of codes collectively named GEORAD (GEOmagnetic RADiation) which computes cutoff rigidity, trapped proton and trapped electron environments. The web version of GEORAD is named OLTARIS (On-line Tool for the Assessment of Radiation in Space). GEORAD suite is applicable to radiation environment prediction at LEO, medium earth orbit (MEO) and geosynchronous earth orbit (GEO) at quiet solar periods. GEORAD interest is in the study of long term effect of the trapped environment and therefore it does not account for any short term external field contribution due to solar activity. With the concentration of the paper on the LEO protons only, the paper presents the validation of the trapped proton model within GEORAD with reported measurements from the compact environment anomaly sensor (CEASE) science instrument package, flown onboard the tri-service experiment-5 (TSX-5) satellite during the period of June 2000 to July 2006. The spin stabilized satellite was flown in a 410 × 1710 km, 69° inclination elliptical orbit, allowing it to be exposed to a broad range of the LEO regime. The paper puts particular emphasize on the validation of the differential at 40 MeV, and integral at >40 MeV proton flux profiles, in the vicinity of the south Atlantic anomaly (SAA) region where protons exhibit east-west (EW) anisotropy and have a relatively narrow pitch angle distribution. Within SAA, the EW anisotropy results in different level of exposure to different sections of a formation flying spacecraft such as TSX-5 or ISS. While the magnitude of the EW effect at LEO depends on a multitude of factors such as trapped proton energy, orientation of the spacecraft along the velocity vector and altitude of the spacecraft, the paper draws quantitative conclusions on the combined effect of proton pitch angle and EW anomaly. © 2011 Elsevier B.V. All rights reserved. Source

Thompson J.S.,Christopher Newport University
Estuaries and Coasts | Year: 2015

Intertidal marshes provide an important foraging habitat for resident marsh fishes. However, few studies have considered whether the importance of intertidal foraging is uniform across the adult-size range of marsh fishes or whether size-selective foraging, which has been demonstrated in intertidal habitats, also occurs in subtidal habitats. This study compares diet composition of adult mummichogs (Fundulus heteroclitus) in Hoffler Creek, VA, USA, foraging in intertidal salt marshes with the diet of individuals foraging in the subtidal creek and considers the effect of fish size on gut fullness and consumption of major intertidal and subtidal diet items. Gut fullness was significantly greater in the intertidal salt marsh for small mummichogs (40–60 mm total length), and small mummichogs were significantly more likely than larger individuals to consume several major intertidal diet items, including copepods and ostracods. However, gut fullness was greater in the subtidal creek for large mummichogs (70–90 mm total length (TL)) due to consumption of grass shrimp (Palaemonetes spp.). This diet item was rarely consumed by large mummichogs in the marsh or by smaller mummichogs in either habitat. Modifications to the marsh landscape that affect prey resources for fishes may, therefore, have differing impacts across adult size classes. Although subtidal habitats are not frequently considered important for foraging of marsh fishes, access to shallow, subtidal water may allow larger adults to take advantage of additional prey resources, such as shrimp. © 2014, Coastal and Estuarine Research Federation. Source

Slaba T.C.,NASA | Blattnig S.R.,NASA | Badavi F.F.,Christopher Newport University
Journal of Computational Physics | Year: 2010

The deterministic transport code HZETRN was developed for research scientists and design engineers studying the effects of space radiation on astronauts and instrumentation protected by various shielding materials and structures. In this work, several aspects of code verification are examined. First, a detailed derivation of the light particle (A{less-than above slanted equal above greater-than above slanted equal}4) and heavy ion (A>4) numerical marching algorithms used in HZETRN is given. References are given for components of the derivation that already exist in the literature, and discussions are given for details that may have been absent in the past. The present paper provides a complete description of the numerical methods currently used in the code and is identified as a key component of the verification process. Next, a new numerical method for light particle transport is presented, and improvements to the heavy ion transport algorithm are discussed. A summary of round-off error is also given, and the impact of this error on previously predicted exposure quantities is shown. Finally, a coupled convergence study is conducted by refining the discretization parameters (step-size and energy grid-size). From this study, it is shown that past efforts in quantifying the numerical error in HZETRN were hindered by single precision calculations and computational resources. It is determined that almost all of the discretization error in HZETRN is caused by the use of discretization parameters that violate a numerical convergence criterion related to charged target fragments below 50AMeV. Total discretization errors are given for the old and new algorithms to 100g/cm 2 in aluminum and water, and the improved accuracy of the new numerical methods is demonstrated. Run time comparisons between the old and new algorithms are given for one, two, and three layer slabs of 100g/cm 2 of aluminum, polyethylene, and water. The new algorithms are found to be almost 100 times faster for solar particle event simulations and almost 10 times faster for galactic cosmic ray simulations. © 2010. Source

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