3,111 research outputs found

    Sthenic incompatibilities in rigid bodies motion

    Get PDF
    When a rigid body slides with friction on a surface, hopping motion is observed: this is an everyday phenomenon. In rigid bodies mechanics, this phenomenon appears when it is no longer possible to compute the reaction contact forces. The difficulty is overcome by a motion theory involving velocity discontinuities. Velocity discontinuities may result either from an obstacle which makes impossible to compute the acceleration: this is a cinematic incompatibility or from the impossibility to compute the reaction forces: this is a sthenic incompatibility. We describe two examples: the Klein and Painlevé sthenic incompatibilities. Springer 2006

    Clinical Appraisals of Individual Differences in Treatment Responsivity Among Patients With Psychopathy: A Consensual Qualitative Research Study

    Get PDF
    This study addressed which factors expert clinicians consider crucial in successful completion versus dropout in the mandatory forensic psychiatric treatment of psychopathic patients in the Netherlands. Eleven clinicians were interviewed about patient characteristics, treatment (provider) characteristics, and other factors they deemed associated with failure (transfer to another facility) or completion. The interviews were coded using the guidelines of Consensual Qualitative Research (CQR). Overall, extremely high scores on Psychopathy Checklist–Revised (PCL-R) Facets 1 (Deceitful Interpersonal Style) and 2 (Defective Affective Experience) were thought to impede treatment retention, particularly by its negative impact on motivation and therapeutic relationship. Older patients, those with a prosocial network, and/or patients with comorbid borderline traits appeared to fare better. Treatment success was deemed more likely when treatment goals and expectations are stipulated in a concrete fashion, when an extended and gradual resocialization trajectory is offered, and the treatment team is expert, cohesive, and stable.</p

    Using MMPI–2–RF Correlates to Elucidate the PCL–R and Its Four Facets in a Sample of Male Forensic Psychiatric Patients

    Get PDF
    This study documents the associations between the MMPI-2-RF (Ben-Porath & Tellegen, 2008 ) scale scores and the Psychopathy Checklist Revised (PCL-R; Hare, 2003 ) facet scores in a forensic psychiatric sample. Objectives were to determine how the MMPI-2-RF scales might enhance substantive understanding of the nature of the 4 PCL-R facets and to discern possible implications for the treatment of psychopathic patients. A sample of 127 male forensic psychiatric offenders admitted to a Dutch forensic psychiatric hospital completed the PCL-R and the MMPI-2. Exploratory stepwise regression analyses assessed the prediction of the PCL-R total and its facet scores from MMPI-2-RF scales at its 3 hierarchical levels. Conceptually meaningful results emerged at each level of the MMPI-2-RF hierarchy, including several consistent differences between predictor sets across the facets. Interestingly, ideas of persecution (RC6) was a specific predictor of PCL-R Facet 2, a facet noted for its association with treatment failure. Results are compared and contrasted to the extant body of empirical work to date, and some tentative clinical implications are offered

    Treatment responsiveness of replicated psychopathy profiles.

    Get PDF
    Theory and accumulating data suggest systematic heterogeneity among offenders with psychopathic traits. Several empirical investigations converge on the nature of subtypes, but little is known about differences in treatment responsivity. We have used the 4-facet model of the Psychopathy Checklist-Revised (PCL-R) to provide a framework for detecting subtypes. The present study used the full range of PCL-R scores in a sample of male violent offenders (N = 190) to replicate subtypes found in a partly overlapping sample by Neumann, Vitacco, and Mokros (2016), using Latent Profile Analysis (LPA), and subsequently to examine potential differences in treatment responsivity. Four subtypes emerged. Within the prototypical psychopathic group, the distinction between intent-to-treat and completers was crucial. Prototypical psychopathic offenders were significantly more likely to drop out, but completers appeared to proceed through the different phases of treatment in much the same way as the other groups. Clearly, more research is needed to elucidate treatment interfering mechanisms and their associated patient characteristics, particularly for the prototypical psychopathic group. Developing therapeutic strategies to improve treatment compliance is a necessary step in the development of specialized treatment programs for these difficult patients

    Do We Hold Males and Females to the Same Standard? A Measurement Invariance Study on the Psychopathy Checklist-Revised

    Get PDF
    ABSTRACT Psychopathy in females has been understudied. Extant data on gender comparisons using the predominant measure of assessment in clinical practice, the Psychopathy Checklist Revised (PCL-R), points to a potential lack of measurement invariance (MI). If indeed the instrument does not perform equally (well) in both genders, straightforward comparison of psychopathy scores in males and females is unwarranted. Using a sample of female and male forensic patients (N ¼ 110 and N ¼ 147 respectively), we formally tested for MI in a structural equation modeling framework. We found that the PCL-R in its current form does not attain full MI. Four items showed threshold biases and particularly Factor 2 (the Social Deviance Factor) is gender biased. Based on our findings, it seems reasonable to expect that specific scoring adjustments might go a long way in bringing about more equivalent assessment of psychopathic features in men and women. Only then can we begin to meaningfully compare the genders on the prevalence, structure, and external correlates of psychopath

    How emergency managers (mis?)interpret forecasts

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146849/1/disa12293.pd

    Non-relativistic limit of Randall-Sundrum model: solutions, applications and constraints

    Full text link
    In the Randall-Sundrum model with one brane, we found the approximate and exact solutions for gravitational potentials and accelerations of test bodies in these potentials for different geometrical configurations. We applied these formulas for calculation of the gravitational interaction between two spheres and found the approximate and exact expressions for the relative force corrections to the Newton's gravitational force. We demonstrated that the difference between relative force corrections for the approximate and exact cases increases with the parameter ll (for the fixed distance rr between centers of the spheres). On the other hand, this difference increases with decreasing of the distance between the centers of the spheres (for the fixed curvature scale parameter ll). We got the upper limit for the curvature scale parameter l≲10 μl\lesssim 10\, \mum. For these values of ll, the difference between the approximate and exact solutions is negligible.Comment: LaTex 11 pages, 3 figure

    Electronic transport in films of colloidal CdSe nanocrystals

    Full text link
    We present results for electronic transport measurements on large three-dimensional arrays of CdSe nanocrystals. In response to a step in the applied voltage, we observe a power-law decay of the current over five orders of magnitude in time. Furthermore, we observe no steady-state dark current for fields up to 10^6 V/cm and times as long as 2x10^4 seconds. Although the power-law form of the decay is quite general, there are quantitative variations with temperature, applied field, sample history, and the material parameters of the array. Despite evidence that the charge injected into the film during the measurement causes the decay of current, we find field-scaling of the current at all times. The observation of extremely long-lived current transients suggests the importance of long-range Coulomb interactions between charges on different nanocrystals.Comment: 11 pages, 10 figure
    • …
    corecore