7,085 research outputs found

    Mapping Sex Offender Addresses: The Utility of the Alaska Sex Offender Registry as a Research Data Base

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    The registration of sex offenders was part of a national effort to enhance public safety by permitting law enforcement officials to track the location of convicted sex offenders after their release. All fifty states have enacted legislation requiring persons convicted of various sex-related offenses to register with law enforcement agencies; many states also grant public access to all or a portion of their registries. This document reports on the Alaska Statistical Analysis Center's efforts to improve data accuracy in the Alaska Sex Offender Registry, maintained by the Alaska State Troopers, and to assess the registry's utility as a research tool.Bureau of Justice Statistics, Grant No. 1999-RU-RX-K006Background of the Project / Research Methodology / Results / Utility: Spatial Justice Research / APPENDICES / A. Alaska’s Sex Offender Registration Law / B. Establishment of a Central Registry of Sex Offenders in Alaska / C. Definitions of Offenses for which Convicted Persons Must Register as Sex Offenders in Alask

    Chiral Loops and Ghost States in the Quenched Scalar Propagator

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    The scalar, isovector meson propagator is analyzed in quenched QCD, using the MQA pole-shifting ansatz to study the chiral limit. In addition to the expected short-range exponential falloff characteristic of a heavy scalar meson, the propagator also exhibits a longer-range, negative metric contribution which becomes pronounced for smaller quark masses. We show that this is a quenched chiral loop effect associated with the anomalous structure of the ηâ€Č\eta ' propagator in quenched QCD. Both the time dependence and the quark mass dependence of this effect are well-described by a chiral loop diagram corresponding to an ηâ€Č−π\eta '- \pi intermediate state, which is light and effectively of negative norm in the quenched approximation. The relevant parameters of the effective Lagrangian describing the scalar sector of the quenched theory are determined.Comment: 29 pages, 10 figures, Late

    Effect of Connection Details on the Cyclic Behavior of Nestable Screw Sidelaps

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    The connection strength and stiffness sensitivity of screwed sidelaps in nestable steel decks to screw installation details has been experimentally explored via cyclic testing. The cyclic behavior of sidelaps has been recently incorporated in the high fidelity modeling and seismic evaluation of the steel deck diaphragm in rigid wall - flexible diaphragm buildings, where “unzipping” a sidelap (loss of a significant number of sidelap connections along a deck edge) could significantly reduce the seismic performance of the whole diaphragm. A total of 24 monotonic and cyclic sidelap tests have been performed in the Thin-Walled Structures Laboratory at Johns Hopkins University. Two different screw edge distances, three different deck thicknesses (i.e. 18 gauge 20 gauge, and 22 gauge), and two different screw sizes were included in the test matrix. The screws were installed either “close to the edge” or “far from the edge”. For the “close to the edge” condition the typical 1.5d edge distance limitation in the design specification was not satisfied. Both monotonic and cyclic test results show that the strength of the sidelap connection can be correlated to edge distance and screw installation details. A maximum 25% and 19% difference in the ultimate strength of the screw sidelaps were observed in monotonic and cyclic tests, respectively. The rest results were compared to sidelap strengths in the literature, and potential changes to sidelap strength predictions and installation methods are discussed

    Short distance current correlators: Comparing lattice simulations to the instanton liquid

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    Point to point correlators of currents are computed in quenched QCD using a chiral lattice fermion action, the overlap action. I compare correlators made of exact quark propagators with correlators restricted to low (less than 500 MeV) eigenvalue eigenmodes of the Dirac operator. In many cases they show qualitative resemblence (typically at small values of the quark mass and distances larger than 0.4 fm) and they differ qualitatively at larger quark masses or at very short distance. Lattice results are in qualitative agreement (and in the difference of vector and axial vector channels, quantitative agreement) with the expectations of instanton liquid models. The scalar channel shows the effects of a quenched finite volume zero mode artifact, a negative correlator.Comment: 18 pages, Revtex, 11 postscript figures. Some changes. Version to appear in Phys. Rev.

    Instanton dominance of topological charge fluctuations in QCD?

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    We consider the local chirality of near-zero eigenvectors from Wilson-Dirac and clover improved Wilson-Dirac lattice operators as proposed recently by Horv\'ath et al. We studied finer lattices and repaired for the loss of orthogonality due to the non-normality of the Wilson-Dirac matrix. As a result we do see a clear double peak structure on lattices with resolutions higher than 0.1 fm. We found that the lattice artifacts can be considerably reduced by exploiting the biorthogonal system of left and right eigenvectors. We conclude that the dominance of instantons on topological charge fluctuations is not ruled out by local chirality measurements.Comment: 10 pages, 6 figure

    Moments of generalized parton distributions and quark angular momentum of the nucleon

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    The internal structure of hadrons is important for a variety of topics, including the hadron form factors, proton spin and spin asymmetry in polarized proton scattering. For a systematic study generalized parton distributions (GPDs) encode important information on hadron structure in the entire impact parameter space. We report on a computation of nucleon GPDs based on simulations with two dynamical non-perturbatively improved Wilson quarks with pion masses down to 350MeV. We present results for the total angular momentum of quarks with chiral extrapolation based on covariant baryon chiral perturbation theory.Comment: Presented at 25th International Symposium on Lattice Field Theory, Regensburg, Germany, 30 Jul - 4 Aug 200

    Pathophysiology of acute experimental pancreatitis: Lessons from genetically engineered animal models and new molecular approaches

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    The incidence of acute pancreatitis is growing and worldwide population-based studies report a doubling or tripling since the 1970s. 25% of acute pancreatitis are severe and associated with histological changes of necrotizing pancreatitis. There is still no specific medical treatment for acute pancreatitis. The average mortality resides around 10%. In order to develop new specific medical treatment strategies for acute pancreatitis, a better understanding of the pathophysiology during the onset of acute pancreatitis is necessary. Since it is difficult to study the early acinar events in human pancreatitis, several animal models of acute pancreatitis have been developed. By this, it is hoped that clues into human pathophysiology become possible. In the last decade, while employing molecular biology techniques, a major progress has been made. The genome of the mouse was recently sequenced. Various strategies are possible to prove a causal effect of a single gene or protein, using either gain-of-function (i.e., overexpression of the protein of interest) or loss-of-function studies (i.e., genetic deletion of the gene of interest). The availability of transgenic mouse models and gene deletion studies has clearly increased our knowledge about the pathophysiology of acute pancreatitis and enables us to study and confirm in vitro findings in animal models. In addition, transgenic models with specific genetic deletion or overexpression of genes help in understanding the role of one specific protein in a cascade of inflammatory processes such as pancreatitis where different proteins interact and co-react. This review summarizes the recent progress in this field. Copyright (c) 2005 S. Karger AG, Basel

    Polymer Induced Bundling of F-actin and the Depletion Force

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    The inert polymer polyethylene glycol (PEG) induces a "bundling" phenomenon in F-actin solutions when its concentration exceeds a critical onset value C_o. Over a limited range of PEG molecular weight and ionic strength, C_o can be expressed as a function of these two variables. The process is reversible, but hysteresis is also observed in the dissolution of the bundles, with ionic strength having a large influence. Additional actin filaments are able to join previously formed bundles. Little, if any, polymer is associated with the bundle structure. Continuum estimates of the Asakura-Oosawa depletion force, Coulomb repulsion, and van der Waals potential are combined for a partial explanation of the bundling effect and hysteresis. Conjectures are presented concerning the apparent limit in bundle size
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