2,524 research outputs found

    The misuse of power: the pumpkinification of Claudius

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    As the Spring Undergraduate Research Day approaches, I and fellow members of my Honors 201: Interdisciplinary Studies course wish to present our research on select pieces of work from Classical Greece and Rome. Individually, we took an in-depth look at different, specific literary works composed by famous classical writers. Historians such as Seneca and Homer. In our research we were asked to craft a thesis-driven analysis of our own text. Throughout this process, we were able to discover a great deal about Greek and Roman culture. Furthermore, our research touches upon life's "big questions" and human nature. Overall, each member of our group covers a different element or aspect relating to humanism. We wish to present our findings in a way that the texts and their teachings remain relevant in today's society. (Author abstract)Campion, B. G. (2014). The misuse of power: The pumpkinification of Claudius. Retrieved from http://academicarchive.snhu.ed

    The PASTEL catalogue of stellar parameters

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    The PASTEL catalogue is an update of the [Fe/H] catalogue, published in 1997 and 2001. It is a bibliographical compilation of stellar atmospheric parameters providing (Teff,logg,[Fe/H]) determinations obtained from the analysis of high resolution, high signal-to-noise spectra, carried out with model atmospheres. PASTEL also provides determinations of the one parameter Teff based on various methods. It is aimed in the future to provide also homogenized atmospheric parameters and elemental abundances, radial and rotational velocities. A web interface has been created to query the catalogue on elaborated criteria. PASTEL is also distributed through the CDS database and VizieR. To make it as complete as possible, the main journals have been surveyed, as well as the CDS database, to find relevant publications. The catalogue is regularly updated with new determinations found in the literature. As of Febuary 2010, PASTEL includes 30151 determinations of either Teff or (Teff,logg,[Fe/H]) for 16649 different stars corresponding to 865 bibliographical references. Nearly 6000 stars have a determination of the three parameters (Teff,logg,[Fe/H]) with a high quality spectroscopic metallicity.Comment: 5 pages, accepted for publication in A&A. The PASTEL catalogue can be queried at http://pastel.obs.u-bordeaux1.fr/ or http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/paste

    Traffic modeling and state feedback control for metro lines

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    Abstract-This paper deals with traffic modeling and control design for high-frequency metro lines. A complete discrete-event traffic model pointing out the natural instability of metro lines is presented. The traffic stability properties are analyzed and easyto-implement state feedback traffic control algorithms are designed, which guarantee the system stability. Simulations illustrate the methodology. I

    Natural resources conflicts and the biofuel industry: implications and proposals for Ghana

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    Africa has become an important target producer of the feedstock, Jatropha curcas L (JCL), for biofuel production. This presents opportunities for transforming production, markets and the well-being of farmers and rural populations in developing countries, if deals are well-structured. The history of natural resource use conflicts in Africa has important implications for understanding current resource ecology and the social and political relationships within it. Ghana has had varying resource management regimes in its history. This paper seeks to relate the history of Ghana's natural resources conflicts to the current rush for lands in Ghana forcultivation of JCL and to discuss its implications and opportunities for a sustainable JCL industry in the countly. The colonial and postcolonial land conflicts and politics and the current and potential conflicts and opportunities associated with the JCL indust1y are presented. The paper offers suggestions not only for a sustainable cultivation of Jatropha, but alsofor a biofuel policy in Ghana.Keywords: Biofuel; natural resources conflicts,- land grabbing; Jatrophacurcas; Ghana

    Etudes des déterminants moléculaires impliqués dans la capacité de transmission d'Alternaria brassicicola aux semences d'Arabidopsis thaliana

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    Seed transmission is one on the most efficient way for fungal pathogens to survive and ensure their dispersal. On the other hand, contaminated seeds are compromised on their germination and survival capacities. Hence, we aimed at identifying molecular mechanisms involved in the transmission abilities of seed-borne fungi using the model pathosystem based on Alternaria brassicicola and Arabidopsis thaliana. We analyzed the response of A. brassicicola to various in vitro and in vivo conditions: stress induced by Brassicaceous defenses metabolites (camalexin, brassinin and isothiocyanates), stress related to a water deficiency (desiccation, sorbitol and PEG) and stress occurring during seed colonization through siliques. Concerning the first type of stress, we showed that indolic phytoalexins probably target mitochondria as revealed by altered respiration and mitochondrial membrane potential after short time exposures. Our analyses also revealed that the fungal response to water stress involved hydrophilins-like and eisosomal proteins. We showed that the expression of most of these proteins was dependent of at least one of the three protein kinases AbSch9, AbNik1 and AbHog1. Finally, our in planta analysis revealed an unexpected possible role of chromatin remodeling mechanisms in the regulation of fungal genes expression during seed transmission

    Correlation of Chemical and Physical Test Data for the Environmental Ageing of Tefzel (ETFE)

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    In a similar approach to that used for the previously issued correlation report for Coflon (CAPP/M.10), this report aims to identify any correlations between mechanical property changes and chemical/morphological changes for Tefzel, using information supplied in other MERL and TRI project reports (plus latest data which will be included in final reports for Phase 1). Differences identified with Coflon behaviour will be of scientific interest as well as appropriate to project applications, as Tefzel and Coflon are chemical isomers. Owing to the considerable chemical resistance of Tefzel, much of its testing so far has been based on mechanical properties. Where changes have occurred, chemical analysis can now be targeted more effectively. Relevant test data collated here include: tensile modulus and related properties, permeation coefficients, % crystallinity, and other observations where significant. Fluids based on methanol and amine (Fluid G), a mixture of methane, carbon dioxide and hydrogen sulphide gases plus an aqueous amine solution (Fluid F), and an aromatic oil mix of heptane, cyclohexane, toluene and I-propanol (Fluid 1) have affected Tefzel to varying degrees, and are discussed in some detail herein

    Radio Emission Associated with Ultraluminous X-ray Sources in the Galaxy Merger NGC 3256

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    We present new 6, 3.6, and 2 cm VLA radio observations of the nearby merger system NGC 3256, with resolutions of ~100 pc, which reveal compact radio sources embedded in more diffuse emission at all three wavelengths. The two radio nuclei are partially resolved, but the two dominant compact sources that remain coincide with the two most powerful compact Ultraluminous X-ray sources (ULXs) recently reported by Lira et al. The radio/X-ray ratios for these two sources are too high by factors of >100-1000 to be normal X-ray binaries. However, their radio and X-ray powers and ratios are consistent with low-luminosity active galactic nuclei (LLAGNs), and optical emission lines suggest the presence of a nuclear disk around the northern nucleus. If the two nuclear ULXs are LLAGNs, their associated black holes are separated by only \~1kpc, about 6 times closer to one another than those found recently in the merger galaxy NGC 6240. A third ULX on the outskirts of the merger is also a radio source, and probably is a collection of supernova remnants. The remaining ULXs are not coincident with any source of compact radio emission, and are consistent with expectations for beamed X-ray binaries or intermediate-mass black holes.Comment: Accepted for ApJ (10 pages, 5 figures

    Correlation of Chemical and Physical Test Data for the Environmental Ageing of Tefzel (ETFE)

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    In a similar approach to that used for the previously issued correlation report for Coflon (CAPP/M.10), this report aims to identify any correlations between mechanical property changes and chemical/morphological changes for Tefzel, using information supplied in other MERL and TRI project reports. Differences identified with Coflon behaviour will be of scientific interest as well as appropriate to project applications, as Tefzel and Coflon are chemical isomers. Owing to the considerable chemical resistance of Tefzel, much of its testing so far has been based on mechanical properties. Where changes have occurred, chemical analysis can now be targeted more effectively. Relevant test data collated here include: tensile modulus and related properties, permeation coefficients, % crystallinity, some crack growth resistance measurements, and other observations where significant. Fluids based on methanol and amine (Fluid G), a mixture of methane, carbon dioxide and hydrogen sulphide gases plus an aqueous amine solution (Fluid F), and an aromatic oil mix of heptane, cyclohexane, toluene and 1-propanol (Fluid I) have affected Tefzel to varying degrees, and are discussed in some detail herein

    High Pressure Gas Permeation and Liquid Diffusion Studies of Coflon and Tefzel Thermoplastics

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    The life of fluid-carrying flexible or umbilical pipes during service at elevated temperatures and pressures depends inter alia on their resistance to attack by the fluids present and the rate at which these fluids are absorbed by the pipe lining materials. The consequences of fluid ingress into the thermoplastic lining could mean a) a reduction in its mechanical strength, to increase chances of crack formation and growth and thus a loss of integrity, b) the occurrence of permeation right through the lining material, with pressure build- up in the outer pipe wall construction (of flexible pipes) or chemical attack (from a hostile permeant) on outer layers of reinforcements. Therefore it is important within this project to have relevant permeation data for Coflon and Tefzel thermoplastics: the former is plasticised, the latter is not. A previous report (CAPP/M.2) described experimental equipment and techniques used by MERL when measuring high pressure (up to 5000 psi) gas permeation and liquid diffusion through thermoplastic samples cut from extruded bar or pipe, and provided the basic theory involved. Norsk Hydro are also performing gas permeation tests on pipe sections, at up to 100 bars (1450 psi) pressure or so, and reporting separately. Some comparisons between data from Norsk Hydro and MERL have been made herein. The tests should be considered as complementary, as the Norsk Hydro test has the obvious benefit of using complete pipe sections, whilst MERL can test at much higher pressures, up to 1000 bar if necessary. The sophisticated analytical measuring equipment of Norsk Hydro can distinguish the individual components of mixed gases and hence the various permeation-linked coefficients whereas MERL, in using pressure increase at constant volume to determine permeation rate, is limited to obtaining single gas data, or apparent (or representative) coefficients for a mixed gas as a whole. Except for the initial fluid diffusion data for Tefzel described in CAPP/M.2, the present report covers all aspects of fluid permeation and diffusion for Coflon and Tefzel, including all the pen-neation data accumulated in the project to date. Test gases have mainly been methane (CH4) and carbon dioxide (CO2). More high pressure (HP) gas permeation tests have been performed since the last issue of this report, most being concerned with changes in permeation characteristics brought about by ageing in various relevant fluids. This revision supersedes previous issues

    Correlation of Chemical and Physical Test Data For the Environment Ageing of Coflon (PVDF)

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    This report aims to identify correlations between mechanical property changes and chemical/morphological structure changes for Coflon. It is intended both to illustrate the overall methodology and to indicate the testing that needs to be undertaken in order to obtain correlations. Many fluid exposures have now been carried out on Coflon during the project and many data generated as a result. The report summarises the changes observed in mechanical and physical properties and relates these as well as possible to the chemistry thought to be occurring during ageing. For this purpose, data have been collated from already-issued MERL and TRI technical and progress reports. Most of the mechanical testing of aged testpieces has been performed soon after the completion of the exposure; however, there is of necessity a delay in obtaining chemical analysis of the same testpieces, so that more physical than chemical data are shown. Three fluids have so far caused measurable deterioration of Coflon, these being: methanol (Fluid A), a methanol and amine mixture (Fluid G), and a mixture of methane, carbon dioxide gas and hydrogen sulphide gas plus aqueous amine (Fluid F). Only the effects of these fluids will be dealt with in any detail in this report, although other fluids are assessed to give relevant background information. Relevant test data collated here include: tensile modulus and related properties, mode of sample failure at break, fracture toughness, fatigue crack growth rate and resistance, stress relaxation rate, permeation coefficients, % crystallinity and molecular weight distributions together with changes in fluorine levels, and other observations where appropriate. However, not all of these were obtained for every ageing condition. Because of the wide range of tests employed, and the different ways in which their results are obtained, the following section has been included to serve as a background for making comparisons
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