2,442 research outputs found

    Classical properties of low-dimensional conductors: Giant capacitance and non-Ohmic potential drop

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    Electrical field arising around an inhomogeneous conductor when an electrical current passes through it is not screened, as distinct from 3D conductors, in low-dimensional conductors. As a result, the electrical field depends on the global distribution of the conductivity sigma(x) rather than on the local value of it, inhomogeneities of sigma(x) produce giant capacitances C(omega) that show frequency dependence at relatively low omega, and electrical fields develop in vast regions around the inhomogeneities of sigma(x). A theory of these phenomena is presented for 2D conductors.Comment: 5 pages, two-column REVTeX, to be published in Physical Review Letter

    Structural fluctuations and quantum transport through DNA molecular wires: a combined molecular dynamics and model Hamiltonian approach

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    Charge transport through a short DNA oligomer (Dickerson dodecamer) in presence of structural fluctuations is investigated using a hybrid computational methodology based on a combination of quantum mechanical electronic structure calculations and classical molecular dynamics simulations with a model Hamiltonian approach. Based on a fragment orbital description, the DNA electronic structure can be coarse-grained in a very efficient way. The influence of dynamical fluctuations arising either from the solvent fluctuations or from base-pair vibrational modes can be taken into account in a straightforward way through time series of the effective DNA electronic parameters, evaluated at snapshots along the MD trajectory. We show that charge transport can be promoted through the coupling to solvent fluctuations, which gate the onsite energies along the DNA wire

    Predicting Postprobationary Job Performance of Police Officers Using CPI and MMPI–2–RF Test Data Obtained During Preemployment Psychological Screening

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    We examined associations between prehire California Psychological Inventory (CPI) and prorated Minnesota Multiphasic Personality Inventory–2 Restructured Form (MMPI–2–RF) scores (calculated from MMPI profiles) and supervisor ratings for a sample of 143 male police officers. Substantive scale scores in this sample were meaningfully lower than those obtained by the tests’ normative samples in the case of the MMPI–2–RF and meaningfully higher in the case of the CPI (indicating less psychological dysfunction). Test scores from both instruments showed substantial range restriction, consistent with those produced by members of the police candidate comparison groups (Corey & Ben-Porath, 2014Corey, D. M., & Ben-Porath, Y. S. (2014). User\u27s guide for the MMPI-2-RF Police Candidate Interpretive Report. Minneapolis, MN: University of Minnesota Press. [Google Scholar]; Roberts & Johnson, 2001Roberts, M. D., & Johnson, M. (2001). CPI: Police and public safety selection report technical manual. Unpublished manuscript. Retrieved fromhttp://media.post.ca.gov/. [Google Scholar]). After applying a statistical correction for range restriction, we found a number of meaningful associations between both CPI and MMPI–2–RF substantive scale scores and supervisor ratings. For the MMPI–2–RF, findings for scales from the emotional dysfunction and interpersonal functioning domains of the test were particularly strong. For the CPI, findings for scales indicating conformity with social norms, integrity, and tolerance were strong, as were the findings for an index indicating risk of termination. Hierarchical regression analyses showed that MMPI–2–RF and CPI scores complement each other, accounting for incremental variance in the prediction of job-related variables over and above each other. Implications of these findings for assessment science and practice are discussed

    Examining DBT Day Treatment in Treating Mood Dysregulation Expectancy and Anxiety in Women Diagnosed with Eating Disorders

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    Eating disorders (EDs), particularly anorexia nervosa (AN) and bulimia nervosa (BN), are characterized by emotional and behavioral disturbances in eating patterns and body image that result in significant distress and functional impairment (as reported by APA, (APA dictionary of psychology, American Psychological Association, Washington, DC, 2015)). Ben-Porath and colleagues (Journal of Contemporary Psychotherapy 40:115-123, 2010) have researched the effectiveness of dialectical behavioral therapy (DBT) day treatment program in reducing negative mood regulation and anxiety among women diagnosed with AN, BN, and eating disorder not otherwise specified (EDNOS). The current study extended past research on the effectiveness of DBT day treatment by analyzing the improvement in these patients’ scores on the beck anxiety inventory (BAI) and the generalized expectancy for negative mood regulation (NMR) Scale after treatment. We compared pre- and post-treatment scores using paired samples t-tests. We also examined rates of clinically significant change in these areas post-treatment. The results indicated that participants demonstrated a reduction in expectancies for negative mood dysregulation and anxiety after undergoing DBT day treatment for EDs. Limitations and implications of this study are discussed

    Descriptive Profiles of the MMPI-2-Restructured Form (MMPI-2-RF) across a National Sample of Four Veteran Affairs Treatment Settings

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    This investigation provides descriptive information on substantive scale scores from the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) across four common service locations within Veterans Affairs (VA): PTSD clinical team, individual substance use treatment, primary medical care, and residential polytrauma rehabilitation. Test protocols for these four service settings are drawn from a national sample of all MMPI-2-RF and converted MMPI-2 administrations between January 1, 2008 and May 31, 2015 using the VA Mental Health Assist system at any VA across the United States. Frequency of substantive scale elevation and descriptive findings are examined. Results of this investigation suggest that there are differences between VA service locations on the MMPI-2-RF substantive scales, the magnitude of difference depends on the substantive scale examined, and the pattern of elevation within service location follows common clinical concerns for the settings. Implications for the clinical use, and research with, the MMPI-2-RF within the VA and with the veteran population are discussed. The views expressed in this manuscript do not reflect those of the Department of Veteran Affairs or of the United States Government

    Quantum transport through a DNA wire in a dissipative environment

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    Electronic transport through DNA wires in the presence of a strong dissipative environment is investigated. We show that new bath-induced electronic states are formed within the bandgap. These states show up in the linear conductance spectrum as a temperature dependent background and lead to a crossover from tunneling to thermal activated behavior with increasing temperature. Depending on the strength of the electron-bath coupling, the conductance at the Fermi level can show a weak exponential or even an algebraic length dependence. Our results suggest a new environmental-induced transport mechanism. This might be relevant for the understanding of molecular conduction experiments in liquid solution, like those recently performed on poly(GC) oligomers in a water buffer (B. Xu et al., Nano Lett 4, 1105 (2004)).Comment: 5 pages, 3 figure
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