19,340 research outputs found

    Adiabatic and Non-Adiabatic Contributions to the Free Energy from the Electron-Phonon Interaction for Na, K, Al, and Pb

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    We calculate the adiabatic contributions to the free energy due to the electron--phonon interaction at intermediate temperatures, 0kBT<ϵF0 \leqslant k_{B} T < \epsilon_{F} for the elemental metals Na, K, Al, and Pb. Using our previously published results for the nonadiabatic contributions we show that the adiabatic contribution, which is proportional to T2T^{2} at low temperatures and goes as T3T^{3} at high temperatures, dominates the nonadiabatic contribution for temperatures above a cross--over temperature, TcT_{c}, which is between 0.5 and 0.8 TmT_{m}, where TmT_{m} is the melting temperature of the metal. The nonadiabatic contribution falls as T1T^{-1} for temperatures roughly above the average phonon frequency.Comment: Updated versio

    The Elder Economic Security Standard(TM) Index for California, 2007: County Amounts, Comparisons and Components

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    Provides county-by-county data on how much income retirees need to make ends meet, how it compares with the Federal Poverty Line, and by how much the maximum Supplemental Security Income payment and average Social Security payment each fall short

    The Health of Aging Lesbian, Gay and Bisexual Adults in California

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    Examines rates of diabetes, hypertension, poor mental health, physical disability, and fair or poor self-reported health status among homosexual adults ages 50 to 70 compared with their heterosexual peers. Recommends enhancing policies and practices

    A Multiwavelength Investigation of Unidentified EGRET Sources

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    Statistical studies indicate that the 271 point sources of high-energy gamma rays belong to two groups: a Galactic population and an isotropic extragalactic population. Many unidentified extragalactic sources are certainly blazars, and it is the intention of this work to uncover gamma-ray blazars missed by previous attempts. Until recently, searches for blazar counterparts to unidentified EGRET sources have focused on finding AGN that have 5-GHz radio flux densities S_5 near or above 1 Jy. However, the recent blazar identification of 3EG J2006-2321 (S_5 = 260 mJy) and other work suggest that careful studies of weaker flat-spectrum sources may be fruitful. In this spirit, error circles of 4 high-latitude unidentified EGRET sources have been searched for 5-GHz sources. The gamma-ray sources are 3EG J1133+0033, 3EG J1212+2304, 3EG J1222+2315, and 3EG J1227+4302. Within the error contours of each of the four sources are found 6 radio candidates; by observing the positions of the radio sources with the 0.81-m Tenagra II telescope it is determined that 14 of these 24 radio sources have optical counterparts with R < 22. Eight of these from two different EGRET sources have been observed in the B, V, and R bands in more than one epoch and the analysis of these data is ongoing. Any sources that are found to be variable will be the objects of multi-epoch polarimetry studies.Comment: 6 pages, 2 tables. To appear in Astrophysics & Space Scienc

    DichroMatch: a website for similarity searching of circular dichroism spectra

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    Circular dichroism (CD) spectroscopy is a widely used method for examining the structure, folding and conformational changes of proteins. A new online CD analysis server (DichroMatch) has been developed for identifying proteins with similar spectral characteristics by detecting possible structurally and functionally related proteins and homologues. DichroMatch includes six different methods for determining the spectral nearest neighbours to a query protein spectrum and provides metrics of how similar these spectra are and, if corresponding crystal structures are available for the closest matched proteins, information on their secondary structures and fold classifications. By default, DichroMatch uses all the entries in the Protein Circular Dichroism Data Bank (PCDDB) for its comparison set, providing the broadest range of publicly available protein spectra to match with the unknown protein. Alternatively, users can download or create their own specialized data sets, thereby enabling comparisons between the structures of related proteins such as wild-type versus mutants or homologues or a series of spectra of the same protein under different conditions. The DichroMatch server is freely available at http://dichromatch.cryst.bbk.ac.uk

    Vortex interaction, chaos and quantum probabilities

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    The motion of a single vortex is able to originate chaos in the quantum trajectories defined in Bohm's interpretation of quantum mechanics. In this Letter, we show that this is also the case in the general situation, in which many interacting vortices exist. This result gives support to recent attempts in which Born's probability rule is derived in terms of an irreversible time evolution to equilibrium, rather than being postulated.Comment: 4 pages, 4 figure

    “Free Will and Affirmation: Assessing Honderich’s Third Way”

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    In the third and final part of his A Theory of Determinism (TD) Ted Honderich addresses the fundamental question concerning “the consequences of determinism.” The critical question he aims to answer is what follows if determinism is true? This question is, of course, intimately bound up with the problem of free will and, in particular, with the question of whether or not the truth of determinism is compatible or incompatible with the sort of freedom required for moral responsibility. It is Honderich’s aim to provide a solution to “the problem of the consequences of determinism” and a key element of this is his articulation and defence of an alternative response to the implications of determinism that collapses the familiar Compatibilist/Incompatibilist dichotomy. Honderich offers us a third way – the response of “Affirmation” (HFY 125-6). Although his account of Affirmation has application and relevance to issues and features beyond freedom and responsibility, my primary concern in this essay will be to examine Honderich’s theory of “Affirmation” as it concerns the free will problem
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