5,459 research outputs found

    Alien Registration- Kidd, James H. (Boothbay, Lincoln County)

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    https://digitalmaine.com/alien_docs/13220/thumbnail.jp

    Brief Studies

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    The Lutheran Church as Evaluated by a Searcher An Outsider Comes in and Looks Bac

    Fine Details of the Nodal Electronic Excitations in Bi2_2Sr2_2CaCu2_2O8+δ_{8+\delta}

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    Very high energy resolution photoemission experiments on high quality samples of optimally doped Bi2_2Sr2_2CaCu2_2O8+δ_{8+\delta} show new features in the low-energy electronic excitations. A marked change in the binding energy and temperature dependence of the near-nodal scattering rates is observed near the superconducting transition temperature, TCT_C. The temperature slope of the scattering rate measured at low energy shows a discontinuity at ~TCT_C. In the superconducting state, coherent excitations are found with the scattering rates showing a cubic dependence on frequency and temperature. The superconducting gap has a d-wave magnitude with negligible contribution from higher harmonics. Further, the bi-layer splitting has been found to be finite at the nodal point.Comment: 5 pages, 4 figure

    On the Reconstructed Fermi Surface in the Underdoped Cuprates

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    The Fermi surface topologies of underdoped samples the high-Tc superconductor Bi2212 have been measured with angle resolved photoemission. By examining thermally excited states above the Fermi level, we show that the Fermi surfaces in the pseudogap phase of underdoped samples are actually composed of fully enclosed hole pockets. The spectral weight of these pockets is vanishingly small at the anti-ferromagnetic zone boundary, which creates the illusion of Fermi "arcs" in standard photoemission measurements. The area of the pockets as measured in this study is consistent with the doping level, and hence carrier density, of the samples measured. Furthermore, the shape and area of the pockets is well reproduced by a phenomenological model of the pseudogap phase as a spin liquid.Comment: 4 pages, 4 figures. Submitted to Physics Review Letter

    ALTERATIONS IN PROTEIN AND NUCLEIC ACID METABOLISM OF LYMPHOMA 6C3HED-OG CELLS IN MICE GIVEN GUINEA PIG SERUM

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    Lymphoma 6C3HED-OG cells, known from previous work to be susceptible to the effects of guinea pig serum in vivo and dependent upon extrinsic asparagine for protein synthesis and growth in vitro, remained for the most part morphologically intact and countable in the electronic cell counter following exposures of 1 and 2 hr to the effects of heated (56°C, 30 min) guinea pig serum injected into the peritoneal cavities of mice in which the lymphoma cells were growing rapidly; after exposures of 4 and 6 hr the bulk of the -OG cells remained still intact and countable in the cell counter, though by this time a small proportion of them (5 to 12%) proved stainable with eosin in wet preparations) hence were presumably nonviable. After 12, 16, and 24 hr of exposure, however, the bulk of the -OG cells were either lysed or fragmented, to the extent that they did not register in the cell counter. Morphologic studies of the cells exposed 16 and 24 hr to the effects of heated guinea pig serum in vivo, disclosed that most of the cells then remaining were either frankly necrotic or greatly altered otherwise, marked vacuolation of the cytoplasm being the most conspicuous alteration in cells not yet obviously necrotic. Long before the bulk of the Lymphoma 6C3HED-OG cells had become conspicuously changed morphologically following exposure to the effects of heated guinea pig serum in vivo, they manifested striking alterations in protein metabolism, as was disclosed by "pulse" studies with radioactive valine. For example, the protein metabolism of -OG cells, as measured by their incorporation of L-valine-C14, was sharply curtailed following 15 min of exposure to heated guinea pig serum in vivo, as compared with valine incorporation by cells labeled immediately after exposure to the guinea pig serum. Following exposure to heated guinea pig serum during 60 min, -OG cells incorporated less than half as much L-valine-C14 as did cells labeled immediately after exposure, and the incorporation of L-valine-C14 was still less after 120 min of exposure. By contrast, Lymphoma -RG1 cells, known from previous work to be wholly insusceptible to the effects of guinea pig serum in vivo and independent of need for extrinsic asparagine for protein synthesis and growth in vitro, showed no curtailment whatever of protein synthesis following exposures to the effects of heated guinea pig serum in vivo during periods of 15, 60, and 120 min. Reasons are given for considering the prompt inhibition of protein synthesis in the asparagine-dependent -OG cells a direct result of asparagine-deprivation induced in vivo by the injected guinea pig serum, the L-asparaginase of which presumably converted the available L-asparagine of the host to L-aspartic acid that was not taken up by the -OG cells. The synthesis of deoxyribonucleic acid by Lymphoma 6C3HED-OG cells, as measured by the incorporation of thymidme-H3, determined with the aid of liquid scintillation counting and autoradiography, was also altered by exposure of the lymphoma cells to the effects of heated guinea pig serum in vivo, though not during exposures of 15 and 60 min; only after an exposure of 120 min did the population of -OG cells incorporate notably less thymidine-H3 than did control populations, though after 240 min of exposure the -OG cells incorporated less than one-fifth as much tritiated thymidineas had -OG cells exposed to heated guinea pig serum for 60 min or to heated horse serum for periods up to 240 min. Autoradiographs indicated that DNA synthesis by -OG cells normally proceeds at an intense level that leads to some 60% of these cells being heavily labeled in autoradiographs at any given time; after exposure to the effects of heated guinea pig serum during 2 and 4 hr in vivo, however, the lymphoma cells lost their ability to incorporate enough tritiated thymidine to become heavily labeled, but approximately the same proportion of them (56 to 58%) retained their ability to incorporate sufficient tritiated thymidine to become lightly labeled. The possibility is considered that the inhibition of DNA synthesis in the asparagine-dependent -OG cells exposed to the effects of heated guinea pig serum in vivo may be secondary to the previously manifest inhibition of protein synthesis. Further, in tests of ribonucleic acid metabolism of Lymphoma 6C3HED-OG cells after exposure to the effects of heated guinea pig serum in vivo during periods of 15, 60, 120, and 240 min, the findings indicated that the ability of the lymphoma cells to synthesize RNA, as measured by their capacity to incorporate uridine-5-H3, remained unaltered during the exposures of 15, 60, and 120 min, but was substantially reduced following 240 min of exposure. The findings are considered in relation to the probability, disclosed in part by previous studies, that heated guinea pig serum brings about its effects upon Lymphoma 6C3HED-OG cells in vivo by providing active L-asparaginase in large amounts, which presumably converts the available (extracellular) asparagine of the host to aspartic acid, the latter not being taken up by the lymphoma cells in vivo or in vitro. Hence it seems likely that heated guinea pig serum in this way brings about a state of asparagine deprivation that is responsible for the sequential metabolic and morphologic alterations that become manifest in asparagine-dependent Lymphoma 6C3HED-OG cells following their exposure to the effects of guinea pig serum in vivo, as here described

    Automating biomedical data science through tree-based pipeline optimization

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    Over the past decade, data science and machine learning has grown from a mysterious art form to a staple tool across a variety of fields in academia, business, and government. In this paper, we introduce the concept of tree-based pipeline optimization for automating one of the most tedious parts of machine learning---pipeline design. We implement a Tree-based Pipeline Optimization Tool (TPOT) and demonstrate its effectiveness on a series of simulated and real-world genetic data sets. In particular, we show that TPOT can build machine learning pipelines that achieve competitive classification accuracy and discover novel pipeline operators---such as synthetic feature constructors---that significantly improve classification accuracy on these data sets. We also highlight the current challenges to pipeline optimization, such as the tendency to produce pipelines that overfit the data, and suggest future research paths to overcome these challenges. As such, this work represents an early step toward fully automating machine learning pipeline design.Comment: 16 pages, 5 figures, to appear in EvoBIO 2016 proceeding

    Modifications Necessary for Commercial Arbitration Law to Protect Statutory Rights Against Discrimination in Employment: A Discussion and Proposals for Change

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    Published in cooperation with the American Bar Association Section of Dispute Resolutio

    High-energy kink in high-temperature superconductors

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    In conventional metals, electron-phonon coupling, or the phonon-mediated interaction between electrons, has long been known to be the pairing interaction responsible for the superconductivity. The strength of this interaction essentially determines the superconducting transition temperature TC. One manifestation of electron-phonon coupling is a mass renormalization of the electronic dispersion at the energy scale associated with the phonons. This renormalization is directly observable in photoemission experiments. In contrast, there remains little consensus on the pairing mechanism in cuprate high temperature superconductors. The recent observation of similar renormalization effects in cuprates has raised the hope that the mechanism of high temperature superconductivity may finally be resolved. The focus has been on the low energy renormalization and associated "kink" in the dispersion at around 50 meV. However at that energy scale, there are multiple candidates including phonon branches, structure in the spin-fluctuation spectrum, and the superconducting gap itself, making the unique identification of the excitation responsible for the kink difficult. Here we show that the low-energy renormalization at ~50 meV is only a small component of the total renormalization, the majority of which occurs at an order of magnitude higher energy (~350 meV). This high energy kink poses a new challenge for the physics of the cuprates. Its role in superconductivity and relation to the low-energy kink remains to be determined.Comment: 13 pages, 4 figure
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