838 research outputs found
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Safeguards and security considerations for a modular treatment system for plutonium residue stabilization
Five sites in the Department of Energy (DOE) nuclear complex have significant amounts of plutonium residues. The DOE has begun programs for stabilization of these materials, but the existing facilities, infrastructure, and technical capacity are inadequate for the task. Additionally, sufficient funding is not available to enable all the facilities to meet current standards that are required for the facilities to be able to treat the residues. At the request of the DOE Office of Environmental Management, a team was assembled to study the feasibility of using modular systems to stabilize plutonium-bearing residues. This feasibility team prepared a basis document using typical residue profiles and fact sheets that documented treatment activities and operational programs that were required. From this basis document, a design team prepared a preconceptual design and a cost and schedule estimate for a stand-alone modular system to treat the residues. The modular treatment system was designed to be broken into functional units (modules) that are individually packaged and portable. These modules were designed to consider all operational phases including safeguards and security. This discussion will present the safeguards and security considerations and techniques that were identified for the modular treatment system
A chirped-pulse Fourier-transform microwave/pulsed uniform flow spectrometer. I. The low-temperature flow system
We report the development of a new instrument that combines chirped-pulse microwave spectroscopy with a pulsed uniform supersonic flow. This combination promises a nearly universal detection method that can deliver isomer and conformer specific, quantitative detection and spectroscopic characterization of unstable reaction products and intermediates, product vibrational distributions, and molecular excited states. This first paper in a series of two presents a new pulsed-flow design, at the heart of which is a fast, high-throughput pulsed valve driven by a piezoelectric stack actuator. Uniform flows at temperatures as low as 20 K were readily achieved with only modest pumping requirements, as demonstrated by impact pressure measurements and pure rotational spectroscopy. The proposed technique will be suitable for application in diverse fields including fundamental studies in spectroscopy, kinetics, and reaction dynamics.National Science Foundation (U.S.) (Award MRI-ID 1126380
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Design impacts of safeguards and security requirements for a US MOX fuel fabrication facility
The disposition of plutonium that is no longer required for the nation`s defense is being structured to mitigate risks associated with the material`s availability. In the 1997 Record of Decision, the US Government endorsed a dual-track approach that could employ domestic commercial reactors to effect the disposition of a portion of the plutonium in the form of mixed oxide (MOX) reactor fuels. To support this decision, the Office of Materials Disposition requested preparation of a document that would review US requirements for safeguards and security and describe their impact on the design of a MOX fuel fabrication facility. The intended users are potential bidders for the construction and operation of the facility. The document emphasizes the relevant DOE Orders but also considers the Nuclear Regulatory Commission (NRC) requirements. Where they are significantly different, the authors have highlighted this difference and provided guidance on the impact to the facility design. Finally, the impacts of International Atomic Energy Agency (IAEA) safeguards on facility design are discussed. Security and materials control and accountability issues that influence facility design are emphasized in each area of discussion. This paper will discuss the prepared report and the issues associated with facility design for implementing practical, modern safeguards and security systems into a new MOX fuel fabrication facility
Optical study of the electronic phase transition of strongly correlated YbInCu_4
Infrared, visible and near-UV reflectivity measurements are used to obtain
conductivity as a function of temperature and frequency in YbInCu_4, which
exhibits an isostructural phase-transition into a mixed-valent phase below
T_v=42 K. In addition to a gradual loss of spectral weight with decreasing
temperature extending up to 1.5 eV, a sharp resonance appears at 0.25 eV in the
mixed-valent phase. This feature can be described in terms of excitations into
the Kondo (Abrikosov-Suhl) resonance, and, like the sudden reduction of
resistivity, provides a direct reflection of the onset of coherence in this
strongly correlated electron system.Comment: 4 pages, 3 figures (to appear in Phys. Rev. B
Volume 01
Introduction from Dean Dr. Charles Ross
Three Decades of Digging: Undergraduate Archeology at Longwood by Jessica Fields and Stephanie Neeley
Interactions of Allelopathy and Heat Stress in Plants by Derek W. Hambright and Mary E. Lehman
Inertial Electrostatic Confinement D-D Fusion Device: Construction and Simulation by Andrew R. Grzankowski
Shackled Nim by Zachary Johnson
Development of GC-MS and Chemometric Methods for the Analysis of Accelerants in Arson Cases by Boone M. Prentice
A Comparison of Image Analysis Methods in cDNA Microarrays by Ashley M. Swandby
Perceived Sexual Activity of Short and Long-Term Relationships by Victoria Morgan and Katie Williamson
Elderly Male Communication by Kristine G. Bender
Three Poems: âAdam and Eve and an Orange Treeâ, âThe Name of Everything Before Dyingâ, and âThe âPoet Voiceââ by Katelyn N. Romaine
There\u27s Nothing Like Dancing, After All : Marriage and Gender in the Dance Scenes of Jane Austen\u27s Novels by D. Nicole Swann
Two Poems: âAge Nine with Motherâ and âThe Apple That Crawls Away From the Treeâ by Jessica Fox
Untitled by Mike McAteer
Room 9 by Alex Grabiec
Two Photographs: âGracieâ and âEmilyâ by Laura Nodtvedt
Bowling Lanes Night by Nick Costa
Two Paintings: âCan and Kettleâ and âScarecrowâ by Rachel Wolfe
Exploring Henrik Ibsen\u27s âPerr Gyntâ by Zack Dalton
Creative Writing Scholarship at Longwood University
Music Scholarship at Longwood â Senior Recital Arianne K. Burrus
Longwood University Theater â Peer Gyn
Antitumor activity from antigen-specific CD8 T cells generated in vivo from genetically engineered human hematopoietic stem cells
The goal of cancer immunotherapy is the generation of an effective, stable, and self-renewing antitumor T-cell population. One such approach involves the use of high-affinity cancer-specific T-cell receptors in gene-therapy protocols. Here, we present the generation of functional tumor-specific human T cells in vivo from genetically modified human hematopoietic stem cells (hHSC) using a human/mouse chimera model. Transduced hHSC expressing an HLA-A*0201ârestricted melanoma-specific T-cell receptor were introduced into humanized mice, resulting in the generation of a sizeable melanoma-specific naĂŻve CD8^+ T-cell population. Following tumor challenge, these transgenic CD8^+ T cells, in the absence of additional manipulation, limited and cleared human melanoma tumors in vivo. Furthermore, the genetically enhanced T cells underwent proper thymic selection, because we did not observe any responses against nonâHLA-matched tumors, and no killing of any kind occurred in the absence of a human thymus. Finally, the transduced hHSC established long-term bone marrow engraftment. These studies present a potential therapeutic approach and an important tool to understand better and to optimize the human immune response to melanoma and, potentially, to other types of cancer
The relationships between golf and health:A scoping review
OBJECTIVE: To assess the relationships between golf and health. DESIGN: Scoping review. DATA SOURCES: Published and unpublished reports of any age or language, identified by searching electronic databases, platforms, reference lists, websites and from consulting experts. REVIEW METHODS: A 3-step search strategy identified relevant published primary and secondary studies as well as grey literature. Identified studies were screened for final inclusion. Data were extracted using a standardised tool, to form (1) a descriptive analysis and (2) a thematic summary. RESULTS AND DISCUSSION: 4944 records were identified with an initial search. 301 studies met criteria for the scoping review. Golf can provide moderate intensity physical activity and is associated with physical health benefits that include improved cardiovascular, respiratory and metabolic profiles, and improved wellness. There is limited evidence related to golf and mental health. The incidence of golfing injury is moderate, with back injuries the most frequent. Accidental head injuries are rare, but can have serious consequences. CONCLUSIONS: Practitioners and policymakers can be encouraged to support more people to play golf, due to associated improved physical health and mental well-being, and a potential contribution to increased life expectancy. Injuries and illnesses associated with golf have been identified, and risk reduction strategies are warranted. Further research priorities include systematic reviews to further explore the cause and effect nature of the relationships described. Research characterising golf's contribution to muscular strengthening, balance and falls prevention as well as further assessing the associations and effects between golf and mental health are also indicated
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