221 research outputs found

    Arbitration and the Batson Principle

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    As disputants more frequently utilize arbitration to resolve disputes, the likelihood that discriminatory arbitrator selection will occur also increases. While some disputants might consent to selecting an arbitrator for particular reasons, it is troublesome to think that repeat players, such as employers and businesses, might use their greater knowledge and experience with the arbitral process to gain control over the arbitrator selection process through the use of peremptory challenges. Opponents of arbitration have attempted to adopt existing legal arguments to address this problem. Unfortunately, however, neither the state action doctrine nor the use of the existing public policy exception to the enforcement of an arbitration agreement or arbitral award will be successful as a means to challenge the use of discriminatory peremptory strikes. Because existing legal arguments fail to address this growing problem, this Article proposes an amendment to the Federal and Uniform Arbitration Acts to address the problem of discriminatory arbitrator selection. The proposed statute, which would ban discrimination in the selection of an arbitrator on the basis of race, ethnicity, national origin, sex, religion, or sexual orientation, mirrors the classifications that the Batson principle encompasses and thus is justifiable for both practical and constitutional reasons

    Neurokinin-immunoreactivity in human neuroblastomas Evidence for selective expression of the preprotachykinin (PPT) II gene

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    AbstractFactors regulating differentiation of the peripheral nervous system (PNS) have been widely studied in neuroblastomas which are tumors of the PNS. Five neuroblastomas were investigated for their content of tachykinin neuropeptides, which arise from two distinct genes which appear differentially expressed in the PNS. Radioimmunoassay and column chromatography revealed large amounts of neurokinin B in three of these tumors and the absence of substance P, neurokinin A, neuropeptide K and neuropeptide γ from all five tumors. This suggests that neuroblastomas can selectively express the preprotachykinin (PPT) II gene and that they may be valuable for investigating the factors involved in the regulation of these two structurally-related neuropeptide genes

    An ancient pathway combining carbon dioxide fixation with the generation and utilization of a sodium ion gradient for ATP synthesis

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    Synthesis of acetate from carbon dioxide and molecular hydrogen is considered to be the first carbon assimilation pathway on earth. It combines carbon dioxide fixation into acetyl-CoA with the production of ATP via an energized cell membrane. How the pathway is coupled with the net synthesis of ATP has been an enigma. The anaerobic, acetogenic bacterium Acetobacterium woodii uses an ancient version of this pathway without cytochromes and quinones. It generates a sodium ion potential across the cell membrane by the sodium-motive ferredoxin:NAD oxidoreductase (Rnf). The genome sequence of A. woodii solves the enigma: it uncovers Rnf as the only ion-motive enzyme coupled to the pathway and unravels a metabolism designed to produce reduced ferredoxin and overcome energetic barriers by virtue of electron-bifurcating, soluble enzymes

    Differences in structure and dynamics of ternary Pd–Ni-based bulk metallic glasses containing sulfur or phosphorous

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    The composition Pd31_{31}Ni42_{42}S27_{27} has been shown to be the best glass former in the family of recently discovered glass forming PdNiS alloys. In this study, this sample system was systematically investigated using fluctuation- and correlation electron microscopy of which the results are compared to a Pd40_{40}Ni40_{40}P20_{20} bulk metallic glass that serves as a model system for metallic glasses. Strong differences in the local atomic correlations beyond the short-range order were observed, which are assumed to be a reason for their discrepancy in thermal stability. The relaxation dynamics at room temperature revealed faster dynamics in the sulfur-containing Pd31_{31}Ni42_{42}S27_{27} glass

    Evidence for Glass–glass Interfaces in a Columnar Cu–Zr Nanoglass

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    Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable

    Host Imprints on Bacterial Genomes—Rapid, Divergent Evolution in Individual Patients

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    Bacteria lose or gain genetic material and through selection, new variants become fixed in the population. Here we provide the first, genome-wide example of a single bacterial strain's evolution in different deliberately colonized patients and the surprising insight that hosts appear to personalize their microflora. By first obtaining the complete genome sequence of the prototype asymptomatic bacteriuria strain E. coli 83972 and then resequencing its descendants after therapeutic bladder colonization of different patients, we identified 34 mutations, which affected metabolic and virulence-related genes. Further transcriptome and proteome analysis proved that these genome changes altered bacterial gene expression resulting in unique adaptation patterns in each patient. Our results provide evidence that, in addition to stochastic events, adaptive bacterial evolution is driven by individual host environments. Ongoing loss of gene function supports the hypothesis that evolution towards commensalism rather than virulence is favored during asymptomatic bladder colonization

    Dynamical-Friction Galaxy-Gas Coupling and Cluster Cooling Flows

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    We revisit the notion that galaxy motions can efficiently heat intergalactic gas in the central regions of clusters through dynamical friction. For plausible values of the galaxy mass-to-light ratio, the heating rate is comparable to the cooling rate due to X-ray emission. Heating occurs only for supersonic galaxy motions, so the mechanism is self-regulating: it becomes efficient only when the gas sound speed is smaller than the galaxy velocity dispersion. We illustrate with the Perseus cluster, assuming a stellar mass-to-light ratio for galaxies in the very central region with the dark-matter contribution becoming comparable to this at some radius rsr_s. For r_s \la 400 {\rm kpc} \sim 3 r_{\rm cool}--corresponding to an average mass-to-light ratio of ∼10\sim10 inside that radius--the dynamical-friction coupling is strong enough to provide the required rate of gas heating. The measured sound speed is smaller than the galaxy velocity dispersion, as required by this mechanism. With this smaller gas temperature and the observed distribution of galaxies and gas, the energy reservoir in galactic motions is sufficient to sustain the required heating rate for the lifetime of the cluster. The galaxies also lose a smaller amount of energy through dynamical friction to the dark matter implying that non--cooling-flow clusters should have flat-cored dark-matter density distributions.Comment: Six pages, 4 figs, Monthly Notices styl

    The slope of the mass profile and the tilt of the fundamental plane in early-type galaxies

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    We present a survey, using the Chandra X-ray observatory, of the central gravitating mass profiles in a sample of 10 galaxies, groups and clusters, spanning ~2 orders of magnitude in virial mass. We find the total mass distributions from ~0.2--10Re, where Re is the optical effective radius of the central galaxy, are remarkably similar to powerlaw density profiles. The negative logarithmic slope of the mass density profiles, alpha, systematically varies with Re, from alpha=2, for systems with Re~4kpc to alpha=1.2 for systems with Re>30kpc. Departures from hydrostatic equilibrium are likely to be small and cannot easily explain this trend. We show that the conspiracy between the baryonic (Sersic) and dark matter (NFW/ Einasto) components required to maintain a powerlaw total mass distribution naturally predicts an anti-correlation between alpha and Re that is very close to what is observed. The systematic variation of alpha with Re implies a dark matter fraction within Re that varies systematically with the properties of the galaxy in such a manner as to reproduce, without fine tuning, the observed tilt of the fundamental plane. We speculate that establishing a nearly powerlaw total mass distribution is therefore a fundamental feature of galaxy formation and the primary factor which determines the tilt of the fundamental plane.Comment: 10 pages, 5 figures, 2 tables. Accepted for publication in MNRAS. Minor revisions to match accepted versio
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