1,997 research outputs found

    The Public Career of Joseph Alexander Mabry

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    The aim of this investigation into the career of General Joseph Alexander Mabry has been to determine, if possible, the character of this man who had had such a noteworthy career in Tennessee public affairs. The great majority of the source material used on General Mabry has been from original, contemporary sources, since, to date, there has been little written on him by historians. The scope of this paper has been limited by necessity to his public activities, as they are the only ones upon which there is any information available. General Mabry\u27s activities as railroad entrepreneur, land owner, politician and journalist are the facets of his kaleidoscopic career around which this thesis has been centered. It is from the examination of his machinations in these areas that one must arrive at any conclusions which he is to make concerning General Mabry. This writer has duly examined the source material but has been unable to arrive at any concrete conclusions. For this reason it is felt that perhaps General Mabry must continue to occupy an uncertain position in the history of East Tennessee

    Remarkable Lives: Rachel Taylor in conversation with Jerome Carson

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    Purpose – The purpose of this paper is to provide a profile of Rachel Taylor. Design/methodology/approach – Rachel provides a short biographical account and is then interviewed by Jerome. In her biography she discusses her search for happiness and belonging. Findings – Rachel talks about focussing on what we are good at, what we love and how discovery can ignite that spark of hope that there can be better than what has gone before. Research limitations/implications – Rachel’s story shows the potential that lies not just within some of us, but all of us. It is but one story, but its message is sure to touch many. Practical implications – How do services promote hope and build resilience and wellbeing? While another service user said recovery was about “coping with your illness and having a meaningful life,” (McManus et al, 2009), services have perhaps focussed too much on symptom reduction and not enough on helping people find meaning and purpose. Social implications – Rachel asks the question is Positive Psychology a movement for all or is it just for the elite? Originality/value – Rachel is someone who has discovered for herself the benefits of Positive Psychology. Hopefully her own discovery will lead to her bringing this promising approach to people with mental health problem

    A Gardening Metaphor: A Framework for Closing Racial Achievement Gaps in American Public Education System

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    The overarching purpose of this article is to introduce A Gardening Metaphor (AGM) as an evolving framework for accelerating the closure of racial achievement gaps in America. Toward this end, we provide: (a) an examination of the racial disparities in education that are disproportionately experienced by Black children; (b) a rationale for why racial achievement gaps must be closed; (c) an introduction to components of AGM; and (d) discussion of AGM gap closing potential through case study with implication for research and practice

    Strong rules for discarding predictors in lasso-type problems

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    We consider rules for discarding predictors in lasso regression and related problems, for computational efficiency. El Ghaoui et al (2010) propose "SAFE" rules that guarantee that a coefficient will be zero in the solution, based on the inner products of each predictor with the outcome. In this paper we propose strong rules that are not foolproof but rarely fail in practice. These can be complemented with simple checks of the Karush- Kuhn-Tucker (KKT) conditions to provide safe rules that offer substantial speed and space savings in a variety of statistical convex optimization problems.Comment:

    Let Me Go Back

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    https://digitalcommons.library.umaine.edu/mmb-vp/3246/thumbnail.jp

    It\u27s a Way That They Have in Chicago

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    https://digitalcommons.library.umaine.edu/mmb-vp/5500/thumbnail.jp

    Morphology of the normal human lens

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    Purpose. To provide a quantitative, morphologic description of differentiated lens fiber cells in all regions of aged normal human lenses. Methods. Transparent normal human lenses (age range, 44 to 71 years) were examined with correlative transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Vibratome sections allowed examination of internal structures, whereas dissected whole lenses revealed surface characteristics. Additionally, image analysis was used to measure cross-sectional areas of fiber cells. Results. Approximate regional dimensions (percentage of diameter and thickness, respectively) were determined for whole lenses : cortex 16%, 17% ; adult nucleus 24%, 21% ; juvenile nucleus 12%, 9% ; fetal nucleus 45%, 49% ; and embryonic nucleus 3%, 4%. Cortical cells were irregularly hexagonal, and the average cross-sectional area measured 24 ± 9 μm2. Adult nuclear cells were flattened with intricate membranous interdigitations and an area of 7 ± 2 μm2. Juvenile nuclear cells had an area of 14 ± 5 μm2. Fetal nuclear cells were rounded with an area of 35 ± 22 μm2. Embryonic nuclear cells also were rounded and had a variable area of 80 ± 68 μm2. Fiber cell cytoplasm in all lens regions appeared smooth in texture and homogeneous in staining density. Conclusions. Both TEM and SEM are necessary to obtain a complete description of fiber cells. Cross-sections of fibers give new insights into the lamellar organization of the lens, indicating that each region has characteristic cell shapes and sizes. Furthermore, average dimensions were used to demonstrate that the number of cells and approximate growth rates vary significantly between adjacent regions

    Study of the magnetite to maghemite transition using microwave permittivity and permeability measurements

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    The microwave cavity perturbation (MCP) technique is used to identify the transition from magnetite (Fe3O4) to the meta-stable form of maghemite (γ-Fe2O3). In this study Fe3O4 was annealed at temperatures from 60 to 300 °C to vary the oxidation. Subsequent to annealing, the complex permittivity and magnetic permeability of the iron oxide powders were measured. The transition to γ-Fe2O3 was corroborated with x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). XRD, XPS and VSM implied that the starting powder was consistent with Fe3O4 and the powders annealed at more than 200 °C were transitioning to γ-Fe2O3. The MCP measurements gave large differences in both complex permittivity and magnetic permeability of the two phases in the frequency range of 2.5–10.2 GHz. Magnetic permeability decreased with annealing temperature, though magnetic losses showed frequency dependent behaviour. Complex permittivity measurements showed a large decrease in both dielectric constant and losses at all measurement frequencies, as well as a prominent loss peak centred around the phase transition temperatures. We interpret the loss peak as being a consequence of field effects due to an intermediate multi-phase mixture. Additionally, almost no frequency dependence was observed. The reduction in complex permittivity implies that the Feoct2+\text{Fe}_{\text{oct}}^{2+} cations in the lattice provide a significant contribution to polarization at microwave frequencies and the effects of Feoct3+\text{Fe}_{\text{oct}}^{3+} are nominal in comparison. The change in loss can be explained as a combination of the differences in the effective conductivity of the two phases (i.e. Fe3O4 exhibits electron-hopping conduction whereas the presence of vacancies in γ-Fe2O3 nullifies this). This shows that the non-invasive MCP measurements serve as a highly sensitive and versatile method for looking at this phase transition in iron and potentially the effects of oxidation states on the polarization in other iron oxides

    The Post-Common Envelope and Pre-Cataclysmic Binary PG 1224+309

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    We have made extensive spectroscopic and photometric observations of PG 1224+309, a close binary containing a DA white dwarf primary and an M4+ secondary. The H alpha line is in emission due to irradiation of the M-star by the hot white dwarf and is seen to vary around the orbit. From the radial velocities of the H alpha line we derive a period of P = 0.258689 +/- 0.000004 days and a semi-amplitude of K_Halpha = 160 +/- 8 km/s. We estimate a correction Delta_K = 21 +/- 2 km/s, where K_M = K_Halpha + Delta_K. Radial velocity variations of the white dwarf reveal a semi-amplitude of K_WD = 112 +/- 14 km/s. The blue spectrum of the white dwarf is well fit by a synthetic spectrum having T_eff = 29,300 K and log(g) = 7.38. The white dwarf contributes 97% of the light at 4500 Angstroms and virtually all of the light blueward of 3800 Angstroms. No eclipses are observed. The mass inferred for the white dwarf depends on the assumed mass of the thin residual hydrogen envelope: 0.40 < M_WD < 0.45 solar masses for hydrogen envelope masses of 0 < M_H < 4.0E-4 solar masses. We argue that the mass of the white dwarf is closer to 0.45 solar masses, hence it appears that the white dwarf has a relatively large residual hydrogen envelope. The mass of the M-star is then M_M = 0.28 +/- 0.05 solar masses, and the inclination is i = 77 +/- 7 degrees. We discuss briefly how PG 1224+309 may be used to constrain theories of close binary star evolution, and the past and future histories of PG 1224+309 itself. The star is both a ``post-common envelope'' star and a ``pre-cataclysmic binary'' star. Mass transfer by Roche-lobe overflow should commence in about 10 Gyr.Comment: 17 pages, 8 figures, AAS LaTeX, to appear in AJ, March 199
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