3,853 research outputs found

    Theme and Variations

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    State constitutions are worth the attention. They are, and have always been, different from the United States Constitution. Because state constitutions are typically easier to replace or amend than the United States Constitution, they reflect the political movements that have swept the country from time to time. As Professor Tarr has observed, provisions based in Jacksonian Democracy, Populism, and the Progressive movement have caused a layering in many state documents, which has affected both substance and interpretation. This makes the study of state constitutions interesting, and important too, because the themes might be similar from state to state, but the variations are remarkably different. Those variations make (and reflect) a qualitative difference in popular attitudes, government activities, and daily life in each of America\u27s fifty separate communities. Professor Robert Williams\u27s textbook, State Constitutional Law: Cases and Materials, does a remarkably good job in setting forth the themes of, and the variations in, America\u27s state constitutions. This is a challenging job, given the surprising diversity in scope, length, style, subject matter, and solutions among the fifty jurisdictions. But Williams selects divergent examples from the provisions, cases, and commentaries regarding various sections of our constitutions. These, when supplemented with additional local materials, give students a background that will enable them to work with state documents wherever they later practic

    Theme and Variations

    Get PDF
    State constitutions are worth the attention. They are, and have always been, different from the United States Constitution. Because state constitutions are typically easier to replace or amend than the United States Constitution, they reflect the political movements that have swept the country from time to time. As Professor Tarr has observed, provisions based in Jacksonian Democracy, Populism, and the Progressive movement have caused a layering in many state documents, which has affected both substance and interpretation. This makes the study of state constitutions interesting, and important too, because the themes might be similar from state to state, but the variations are remarkably different. Those variations make (and reflect) a qualitative difference in popular attitudes, government activities, and daily life in each of America\u27s fifty separate communities. Professor Robert Williams\u27s textbook, State Constitutional Law: Cases and Materials, does a remarkably good job in setting forth the themes of, and the variations in, America\u27s state constitutions. This is a challenging job, given the surprising diversity in scope, length, style, subject matter, and solutions among the fifty jurisdictions. But Williams selects divergent examples from the provisions, cases, and commentaries regarding various sections of our constitutions. These, when supplemented with additional local materials, give students a background that will enable them to work with state documents wherever they later practic

    Confabulation in children with autism

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    Some children with high-functioning autistic spectrum conditions (ASC) have been noted clinically to produce accounts and responses akin to confabulations in neurological patients. Neurological confabulation is typically associated with abnormalities of the frontal lobes and related structures, and some forms have been linked to poor performance on source monitoring and executive function tasks. ASC has also been linked to atypical development of the frontal lobes, and impaired performance on source monitoring and executive tasks. But confabulation in autism has not to our knowledge previously been examined experimentally. So we investigated whether patterns of confabulation in autism might share similarities with neurologically-based confabulation. Tests of confabulation elicitation, source monitoring (reality monitoring, plus temporal and task context memory) and executive function were administered to four adolescents with ASC who had previously been noted to confabulate spontaneously in everyday life. Scores were compared to a typically developing (TD) and an ASC control group. One confabulating participant was significantly impaired at reality monitoring, and one was significantly worse at a task context test, relative to both the ASC and TD controls. Three of the confabulators showed impairment on measures of executive function (Brixton test; Cognitive Estimates test; Hayling Test B errors) relative to both control groups. Three were significantly poorer than the TD controls on two others (Hayling A and B times), but the ASC control group was also significantly slower at this test than the TD controls. Compared to TD controls, two of the four confabulating participants produced an abnormal number of confabulations during a confabulation elicitation questionnaire, where the ASC controls and TD controls did not differ from each other. These results raise the possibility that in at least some cases, confabulation in autism may be less related to social factors than it is to impaired source memory or poor executive function

    A reduced coupled-mode description for the electron-ion energy relaxation in dense matter

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    We present a simplified model for the electron-ion energy relaxation in dense two-temperature systems that includes the effects of coupled collective modes. It also extends the standard Spitzer result to both degenerate and strongly coupled systems. Starting from the general coupled-mode description, we are able to solve analytically for the temperature relaxation time in warm dense matter and strongly coupled plasmas. This was achieved by decoupling the electron-ion dynamics and by representing the ion response in terms of the mode frequencies. The presented reduced model allows for a fast description of temperature equilibration within hydrodynamic simulations and an easy comparison for experimental investigations. For warm dense matter, both fluid and solid, the model gives a slower electron-ion equilibration than predicted by the classical Spitzer result

    Temperature Relaxation in Hot Dense Hydrogen

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    Temperature equilibration of hydrogen is studied for conditions relevant to inertial confinement fusion. New molecular-dynamics simulations and results from quantum many-body theory are compared with Landau-Spitzer (LS) predictions for temperatures T from 50 eV to 5000 eV, and densities with Wigner-Seitz radii r_s = 1.0 and 0.5. The relaxation is slower than the LS result, even for temperatures in the keV range, but converges to agreement in the high-T limit.Comment: 4 pages PRL style, two figure

    First-principles calculations for the adsorption of water molecules on the Cu(100) surface

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    First-principles density-functional theory and supercell models are employed to calculate the adsorption of water molecules on the Cu(100) surface. In agreement with the experimental observations, the calculations show that a H2O molecule prefers to bond at a one-fold on-top (T1) surface site with a tilted geometry. At low temperatures, rotational diffusion of the molecular axis of the water molecules around the surface normal is predicted to occur at much higher rates than lateral diffusion of the molecules. In addition, the calculated binding energy of an adsorbed water molecule on the surfaces is significantly smaller than the water sublimation energy, indicating a tendency for the formation of water clusters on the Cu(100) surface.Comment: 5 pages, 3 figures, submitted to Phys. Rev.

    Locally Perturbed Random Walks with Unbounded Jumps

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    In \cite{SzT}, D. Sz\'asz and A. Telcs have shown that for the diffusively scaled, simple symmetric random walk, weak convergence to the Brownian motion holds even in the case of local impurities if d2d \ge 2. The extension of their result to finite range random walks is straightforward. Here, however, we are interested in the situation when the random walk has unbounded range. Concretely we generalize the statement of \cite{SzT} to unbounded random walks whose jump distribution belongs to the domain of attraction of the normal law. We do this first: for diffusively scaled random walks on Zd\mathbf Z^d (d2)(d \ge 2) having finite variance; and second: for random walks with distribution belonging to the non-normal domain of attraction of the normal law. This result can be applied to random walks with tail behavior analogous to that of the infinite horizon Lorentz-process; these, in particular, have infinite variance, and convergence to Brownian motion holds with the superdiffusive nlogn\sqrt{n \log n} scaling.Comment: 16 page

    Clustering of Primordial Black Holes. II. Evolution of Bound Systems

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    Primordial Black Holes (PBHs) that form from the collapse of density perturbations are more clustered than the underlying density field. In a previous paper, we showed the constraints that this has on the prospects of PBH dark matter. In this paper we examine another consequence of this clustering: the formation of bound systems of PBHs in the early universe. These would hypothetically be the earliest gravitationally collapsed structures, forming when the universe is still radiation dominated. Depending upon the size and occupation of the clusters, PBH merging occurs before they would have otherwise evaporated due to Hawking evaporation.Comment: 23 pages, 1 figure. Submitted to PR
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