3,425 research outputs found

    Beyond Blue and White: University of Kentucky Presidents and Desegregation, 1941-1987

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    This dissertation fills a gap in the historiography of southern higher education by focusing on five university presidents and their role in the desegregation of a non-elite flagship university in the Upper South. While historian Melissa Keane has studied the presidential role at elite private southern universities during the initial phase of the desegregation process, no study has yet examined desegregation from the president’s office at a southern land-grant university. Building upon historian Peter Wallenstein’s thesis that desegregation is not a single event in an institution’s history but rather an ongoing process, I argue that it was also process that clearly involved the university presidents. Though much has been written about desegregation in Kentucky generally and the University of Kentucky specifically, and the pioneering African American students who desegregated UK, almost no scholarship has focused on the specific role of the UK presidents in the ongoing desegregation process. In much of the existing literature, the presidents are portrayed as spectators, they occupy a backseat, or they sit on the sidelines as the action unfolds. Often their story ends with the initial desegregation of UK’s graduate and undergraduate programs. Passive observers they were not, however. Herman Lee Donovan, Frank Graves Dickey, John Wieland. Oswald, Albert Dennis Kirwan, and Otis Arnold Singletary implemented policies that impacted the course of desegregation at the University of Kentucky

    Impact of Ranch and Market Factors on an Index of Agricultural Holding Period Returns

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    This study develops nominal and real holding period return indices for operating ranches. The indices contain two components, monthly ranch operating profit and capital appreciation. A regression model that determines the effect of various attributes on total market value is used to estimate capital appreciation, and a second model determines operating profit. The two different ranch data series are compared with United States Long Term Government Bonds, the S&P 500 Index and Small Capitalization Stocks. Both ranch indices show very low correlation with the S&P 500 Index and very low or negative betas. Further, both ranch series have excess actual nominal and real returns when compared to expected returns determined from the Capital Asset Pricing Model.

    Valuing remnant vegetation in Central Queensland using choice modelling

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    In the Desert Uplands region of Central Queensland, many pastoralists are clearing vegetation in order to improve cattle grazing production. A choice modelling study was undertaken to provide estimates of the benefits of retaining remnant vegetation that are appropriate for inclusion in a cost benefit analysis of tighter clearing restrictions. Attributes included in the choice model were reductions in the population size of non‐threatened species, the number of endangered species lost to the region, and changes in regional income and employment. A nested logit model was used to model the data in order to avoid violations of the independence of irrelevant alternatives condition. The estimated benefits are reported for several tree clearing policy regimes that are more stringent than those currently applied.Resource /Energy Economics and Policy,

    Obscurin Depletion Impairs Organization of Skeletal Muscle in Developing Zebrafish Embryos

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    During development, skeletal myoblasts differentiate into myocytes and skeletal myotubes with mature contractile structures that are precisely oriented with respect to surrounding cells and tissues. Establishment of this highly ordered structure requires reciprocal interactions between the differentiating myocytes and the surrounding extracellular matrix to form correctly positioned and well-organized attachments from the skeletal muscle to the bony skeleton. Using the developing zebrafish embryo as a model, we examined the relationship between new myofibril assembly and the organization of the membrane domains involved in cell-extracellular matrix interactions. We determined that depletion of obscurin, a giant muscle protein, resulted in irregular cell morphology and disturbed extracellular matrix organization during skeletal muscle development. The resulting impairment of myocyte organization was associated with disturbance of the internal architecture of the myocyte suggesting that obscurin participates in organizing the internal structure of the myocyte and translating those structural cues to surrounding cells and tissues

    Hyperconductivity in fluorphlogopite at 300 K and 1.1 T

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    We report on studies of hyperconductivity in which electric charge moves in a solid in the absence of an applied electric field. This is indicative of a non-Ohmic mechanism. Our results are consistent with charge being carried ballistically by mobile nonlinear lattice excitations called quodons moving along close-packed atomic chains in the cation layers of some silicates. The finding that quodons can trap and carry a charge was first found by the authors in muscovite (Russell F. M. et al., EPL, 120 (2017) 46001), which previously was not possible. In this paper we have also found hyperconductivity in lepidolite, phlogopite and synthetic fluorphlogopite but not in biotite or quartz. We have found that a current continues to flow for many seconds after the creation of quodons is stopped, indicating they have long flight-paths. This shows that quodons are decoupled from phonons, must experience elastic reflection at boundaries and are not stopped by inevitable dislocations or other minor defects. We have also found that quodons can anneal defects caused by mechanical working of crystal faces. The current carried by quodons is unaffected by a magnetic field of 1.1 T.Ministerio de Ciencia e Innovación, PRX18/00360Ministerio de Economía y competitividad, FIS2015-65998- C2-2-PJunta de Andalucía, 2017/FQM-28

    Instability of the Microemulsion Channel in Block Copolymer-Homopolymer Blends

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    Field theoretic simulations are used to predict the equilibrium phase diagram of symmetric blends of AB diblock copolymer with A- and B-type homopolymers. Experiments generally observe a channel of bicontinuous microemulsion (BμE) separating the ordered lamellar (LAM) phase from coexisting homopolymer-rich (A+B) phases. However, our simulations find that the channel is unstable with respect to macrophase separation, in particular, A+B+BμE coexistence at high T and A+B+LAM coexistence at low T. The preference for three-phase coexistence is attributed to a weak attractive interaction between diblock monolayers

    Physical Condition, Sex, and Age-Class of Eastern Red-Backed Salamanders ( Plethodon cinereus

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    Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus). Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields, meadows, and pastures. However, presence and high densities of P. cinereus within agriculturally disturbed habitats may be misleading if these populations exhibit atypical demographic characteristics or decreased physical condition relative to forest populations. We surveyed artificial cover boards from 2004-2005 to compare physical condition, sex ratios, and age-class structure of P. cinereus among woodland, woodland-meadow edge, silvopasture, and meadow sites in the central Appalachian Mountains of southern West Virginia. Physical condition of salamanders was not significantly different among the four habitats. Furthermore, adult sex ratios of P. cinereus typically were not significantly different from 1 : 1 and were similar between forested and non-forested sites, although populations within silvopastures were biased towards females. However, adult salamanders were significantly more abundant than juveniles in all habitat types, with differences most pronounced within meadow habitats. Our study indicates that relatively small, non-forested habitats such as silvopastures and meadows may not adversely affect the overall physical condition or sex ratios of Plethodon cinereus. However, the paucity of juveniles within disturbed meadows indicates that these agriculturally modified habitats may negatively impact reproduction or that immature salamanders are at a physiological or competitive disadvantage in comparison to adults, particularly when surface cover is limited

    Inducing Transport in a Dissipation-Free Lattice with Super Bloch Oscillations

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    Particles in a perfect lattice potential perform Bloch oscillations when subject to a constant force, leading to localization and preventing conductivity. For a weakly-interacting Bose-Einstein condensate (BEC) of Cs atoms, we observe giant center-of-mass oscillations in position space with a displacement across hundreds of lattice sites when we add a periodic modulation to the force near the Bloch frequency. We study the dependence of these "super" Bloch oscillations on lattice depth, modulation amplitude, and modulation frequency and show that they provide a means to induce linear transport in a dissipation-free lattice. Surprisingly, we find that, for an interacting quantum system, super Bloch oscillations strongly suppress the appearance of dynamical instabilities and, for our parameters, increase the phase-coherence time by more than a factor of hundred.Comment: 4 pages, 5 figure

    Repetitive Segmental Structure of the Transducin β Subunit: Homology with the CDC4 Gene and Identification of Related mRNAs

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    Retinal transducin, a guanine nucleotide regulatory protein (referred to as a G protein) that activates a cGMP phosphodiesterase in photoreceptor cells, is comprised of three subunits. We have identified and analyzed cDNA clones of the bovine transducin β subunit that may be highly conserved or identical to that in other G proteins. From the cDNA nucleotide sequence of the entire coding region, the primary structure of a 340-amino acid protein was deduced. The encoded β subunit has a Mr of 37,375 and is comprised of repetitive homologous segments arranged in tandem. Furthermore, significant homology in primary structure and segmental sequence exists between the β subunit and the yeast CDC4 gene product. The Mr 37,375 β subunit polypeptide is encoded by a 2.9-kilobase (kb) mRNA. However, there exists in retina other β-related mRNAs that are divergent from the 2.9-kb mRNA on the basis of oligonucleotide and primer-extended probe hybridizations. All mammalian tissues and clonal cell lines that have been examined contain at least two β-related mRNAs, usually 1.8 and 2.9 kb in length. These results suggest that the mRNAs are the processed products of a small number of closely related genes or of a single highly complex β gene

    Test and Analysis of Sub-Components of Aluminum-Lithium Alloy Cylinders

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    Integrally machined blade-stiffened panels subjected to an axial compressive load were tested and analyzed to observe the buckling, crippling, and postcrippling response of the panels. The panels were fabricated from aluminum-lithium alloys 2195 and 2050, and both alloys have reduced material properties in the short transverse material direction. The tests were designed to capture a failure mode characterized by the stiffener separating from the panel in the postbuckling range. This failure mode is attributed to the reduced properties in the short transverse direction. Full-field measurements of displacements and strains using three-dimensional digital image correlation systems and local measurements using strain gages were used to capture the deformation of the panel leading up to the failure of the panel for specimens fabricated from 2195. High-speed cameras were used to capture the initiation of the failure. Finite element models were developed using an isotropic strain-hardening material model. Good agreement was observed between the measured and predicted responses for both alloys
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