838 research outputs found

    A chirped-pulse Fourier-transform microwave/pulsed uniform flow spectrometer. I. The low-temperature flow system

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    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

    Optical study of the electronic phase transition of strongly correlated YbInCu_4

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    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

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    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: “Adam and Eve and an Orange Tree”, “The Name of Everything Before Dying”, and “The ‘Poet Voice’” 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: “Age Nine with Mother” and “The Apple That Crawls Away From the Tree” by Jessica Fox Untitled by Mike McAteer Room 9 by Alex Grabiec Two Photographs: “Gracie” and “Emily” by Laura Nodtvedt Bowling Lanes Night by Nick Costa Two Paintings: “Can and Kettle” and “Scarecrow” by Rachel Wolfe Exploring Henrik Ibsen\u27s “Perr Gynt” by Zack Dalton Creative Writing Scholarship at Longwood University Music Scholarship at Longwood – Senior Recital Arianne K. Burrus Longwood University Theater – Peer Gyn

    Antitumor activity from antigen-specific CD8 T cells generated in vivo from genetically engineered human hematopoietic stem cells

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    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*0201–restricted melanoma-specific T-cell receptor were introduced into humanized mice, resulting in the generation of a sizeable melanoma-specific naïve 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 non–HLA-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

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    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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