1,766 research outputs found

    Everybody in and nobody out : opportunities, narrative, and the radical flank in the movement for single-payer health care reform

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    Title from PDF of title page (University of Missouri--Columbia, viewed on August 29, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Clarence LoIncludes bibliographical references.Vita.Ph. D. University of Missouri--Columbia 2012"May 2012"In this dissertation, I analyze over twenty years of the United States Single Payer Movement. I began this analysis with the following questions in mind -- What is the Relationship between opportunity and grassroots mobilization? How do activists understand opportunity? What is the role of narrative in this process? I grounded my analysis in a feminist epistemological and methodological stance, which is rooted in the understanding that all knowledge is located and that we can learn much by privileging the voices from marginalized positions. This research involved participant observation, semi-structured interviews, and content analysis. This research has resulted in a significant contribution to social movement theory by further explicating the relationship between opportunity and grassroots opportunity. I argue that social movement actors develop understandings about the opportunities that they face through the practice of narrative. This narrative practice is an integral aspect in the process of pragmatic liberation, or the practice of liberation, through which social movement actors seek to empower themselves and a wider audience of constituents. Even during time periods in which there is less political likelihood that the movement will achieve its goals, movement activists are able to mobilize constituencies by constructing narratives of opportunity outside of the material realm. A more diverse system of narrative practice that is rooted in multiple types of opportunity facilitates greater diversity in movement mobilization.Includes bibliographical reference

    Sources of semiochemicals mediating host finding in Callosobruchus chinensis (Coleoptera: Bruchidae)

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    Bruchid pests such as Callosobruchus chinensis (Linnaeus) endanger stored legume seeds throughout the tropical belt. The chemical composition of the headspace volatiles from healthy and fourth instar larvae-infested cowpea seeds were identified, characterized, and compared using gas chromatography-mass spectrometry. Y-tube olfactometer bioassays were performed to evaluate the effect of these chemicals on the orientation of conspecific adult females. Analysis of volatiles released from healthy and infested seeds revealed qualitative differences for three out of the 17 compounds identified. Dimethyl disulphide, isobutenyl methyl ketone and methyl trisulphide were found only in the blend emitted from infested but not from healthy seeds. Quantitative differences were apparent for tridecane which was released in larger amounts from infested seeds. While volatiles collected from healthy seeds were attractive to female bruchids, volatiles collected from infested seeds were repellent. To test the hypothesis that the qualitative differences in the chemical composition found may be due to insect-derived components, the volatiles from frass and fourth instar larvae combined were analysed. These volatiles contained both of the sulphides emitted from infested seed but not from healthy seeds. Although a limited induction of volatiles from cowpea seeds cannot be excluded, it is postulated that behavioural differences of the female weevils are largely due to insect-derived semiochemicals. The potential use of such semiochemicals as part of an integrated pest management strategy is discusse

    New explicit spike solution -- non-local component of the generalized Mixmaster attractor

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    By applying a standard solution-generating transformation to an arbitrary vacuum Bianchi type II solution, one generates a new solution with spikes commonly observed in numerical simulations. It is conjectured that the spike solution is part of the generalized Mixmaster attractor.Comment: Significantly revised. Colour figures simplified to accommodate non-colour printin

    Coordinate Singularities in Harmonically-sliced Cosmologies

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    Harmonic slicing has in recent years become a standard way of prescribing the lapse function in numerical simulations of general relativity. However, as was first noticed by Alcubierre (1997), numerical solutions generated using this slicing condition can show pathological behaviour. In this paper, analytic and numerical methods are used to examine harmonic slicings of Kasner and Gowdy cosmological spacetimes. It is shown that in general the slicings are prevented from covering the whole of the spacetimes by the appearance of coordinate singularities. As well as limiting the maximum running times of numerical simulations, the coordinate singularities can lead to features being produced in numerically evolved solutions which must be distinguished from genuine physical effects.Comment: 21 pages, REVTeX, 5 figure

    A randomised trial evaluating Bevacizumab as adjuvant therapy following resection of AJCC stage IIB, IIC and III cutaneous melanoma : an update

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    At present, there are no standard therapies for the adjuvant treatment of malignant melanoma. Patients with primary tumours with a high-Breslow thickness (stages IIB and IIC) or with resected loco-regional nodal disease (stage III) are at high risk of developing metastasis and subsequent disease-related death. Given this, it is important that novel therapies are investigated in the adjuvant melanoma setting. Since angiogenesis is essential for primary tumour growth and the development of metastasis, anti-angiogenic agents are attractive potential therapeutic candidates for clinical trials in the adjuvant setting. Therefore, we initiated a phase II trial in resected high-risk cutaneous melanoma, assessing the efficacy of bevacizumab versus observation. In the interim safety data analysis, we demonstrate that bevacizumab is a safe therapy in the adjuvant melanoma setting with no apparent increase in the surgical complication rate after either primary tumour resection and/or loco-regional lymphadenectomy

    Response of female Cydia molesta (Lepidoptera: Tortricidae) to plant derived volatiles

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    Peach shoot volatiles were attractive to mated female oriental fruit moth, Cydia molesta (Busck), in a dual choice arena. No preference was observed between leaf odours from the principle host plant, peach, and the secondary host plant, apple. Twenty-two compounds were identified in headspace volatiles of peach shoots using gas chromatography-mass spectrometry. Green leaf volatiles accounted for more than 50% of the total emitted volatiles. A bioassay-assisted fractionation using different sorbent polymers indicated an attractant effect of compounds with a chain length of 6-8 carbon atoms. The major compounds of this fraction were tested either singly or in combinations for behavioural response of females. Significant bioactivity was found for a three-component mixture of (Z)-3-hexen-1-yl acetate, (Z)-3-hexen-1-ol and benzaldehyde in a 4:1:1 ratio. This synthetic mixture elicited a similar attractant effect as the full natural blend from peach shoots as well as the bioactive fractio

    Initial Hypersurface Formulation: Hamilton-Jacobi Theory for Strongly Coupled Gravitational Systems

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    Strongly coupled gravitational systems describe Einstein gravity and matter in the limit that Newton's constant G is assumed to be very large. The nonlinear evolution of these systems may be solved analytically in the classical and semiclassical limits by employing a Green function analysis. Using functional methods in a Hamilton-Jacobi setting, one may compute the generating functional (`the phase of the wavefunctional') which satisfies both the energy constraint and the momentum constraint. Previous results are extended to encompass the imposition of an arbitrary initial hypersurface. A Lagrange multiplier in the generating functional restricts the initial fields, and also allows one to formulate the energy constraint on the initial hypersurface. Classical evolution follows as a result of minimizing the generating functional with respect to the initial fields. Examples are given describing Einstein gravity interacting with either a dust field and/or a scalar field. Green functions are explicitly determined for (1) gravity, dust, a scalar field and a cosmological constant and (2) gravity and a scalar field interacting with an exponential potential. This formalism is useful in solving problems of cosmology and of gravitational collapse.Comment: 30 pages Latex (IOP) file with 2 IOP style files, to be published in Classical and Quantum Gravity (1998

    Numerical simulations of general gravitational singularities

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    This paper covers some of the current techniques and issues involved in performing numerical simulations of the formation of singularities.Comment: This work was part of the 2006 AEI conference on New Frontiers in Numerical Relativity and was published in an issue of Classical and Quantum Gravity on that conferenc

    Aplicaci?n de un modelo

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    45 p. Recurso Electr?nicoEn este trabajo de grado se presenta un ajuste al modelo de series de tiempo DTGARCH con ruido blanco t-Student usando los retornos diarios del ln del ?ndice BOVESPA y del ?ndice Dow-Jones desde el 12 de diciembre de 2000 hasta el 02 de junio de 2010. La estimaci?n de par?metros del modelo se realiz? a trav?s de la metodolog?a Bayesiana propuesta por Chen, Gerlach y So (2006) y t?cnicas MCMC. Un experimento de simulaci?n muestra que la metodolog?a utilizada es muy efectiva. Por otro lado se realiz? una comparaci?n de la funci?n de varianza condicional del modelo DTGARCH obtenido con la que se obtuvo en los articulos de Zhang y Nieto (2015) donde consideran los modelos autorregresivo de umbrales (TAR) con datos faltantes cuando el proceso del ruido sigue una distribuci?n t-Student, y Moreno y Nieto (2014), donde consideran un modelo TAR cuando el proceso del ruido sigue una distribuci?n Gaussiana. Finalmente se evidenci? que el modelo DTGARCH tiene un buen ajuste y una mejor captura del aspecto heteroced?stico contenido en los datos financieros. Palabras clave: Modelos DTGARCH, estad?stica Bayesiana, funci?n de varianza condicional, t?cnicas MCMC, series de tiempo financieras, volatilidad

    Manufacture of Gowdy spacetimes with spikes

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    In numerical studies of Gowdy spacetimes evidence has been found for the development of localized features (spikes) involving large gradients near the singularity. The rigorous mathematical results available up to now did not cover this kind of situation. In this work we show the existence of large classes of Gowdy spacetimes exhibiting features of the kind discovered numerically. These spacetimes are constructed by applying certain transformations to previously known spacetimes without spikes. It is possible to control the behaviour of the Kretschmann scalar near the singularity in detail. This curvature invariant is found to blow up in a way which is non-uniform near the spike in some cases. When this happens it demonstrates that the spike is a geometrically invariant feature and not an artefact of the choice of variables used to parametrize the metric. We also identify another class of spikes which are artefacts. The spikes produced by our method are compared with the results of numerical and heuristic analyses of the same situation.Comment: 25 page
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