A Bayesian test for the appropriateness of a model in the biomagnetic inverse problem

This paper extends the work of Clarke [1] on the Bayesian foundations of the biomagnetic inverse problem. It derives expressions for the expectation and variance of the a posteriori source current probability distribution given a prior source current probability distribution, a source space weight function and a data set. The calculation of the variance enables the construction of a Bayesian test for the appropriateness of any source model that is chosen as the a priori infomation. The test is illustrated using both simulated (multi-dipole) data and the results of a study of early latency processing of images of human faces. [1] C.J.S. Clarke. Error estimates in the biomagnetic inverse problem. Inverse Problems, 10:77--86, 1994.Comment: 13 pages, 16 figures. Submitted to Inverse Problem

No leader is an island : contextual antecedents to line managers’ constructive and destructive leadership during an organizational intervention

Purpose: Line managers can make or break organizational interventions, yet little is known about what makes them turn in either direction. As leadership does not occur in a vacuum it has been suggested that the organizational context plays an important role. Building on the intervention and leadership literature, we examine if span of control and employee readiness for change are related to line managers’ leadership during an organizational intervention. Design: Leadership is studied in terms of intervention-specific constructive, as well as passive and active forms of destructive, leadership behaviors. As a sample, we use employees (N = 172) from 37 groups working at a process industry plant. Multilevel analyses over two time points, with both survey and organizational register data were used to analyze the data. Findings: The results revealed that span of control was negatively related to constructive leadership and positively related to passive destructive leadership during the intervention. Employee readiness for change was positively related to constructive leadership, and negatively related to both passive and active destructive leadership. Practical implications: Our findings suggest that contextual factors need to be assessed and considered if we want line managers to engage in constructive rather than destructive leadership during interventions. Originality/value: The present study is the first to address line managers’ making or breaking of organizational interventions by examining the influence of context on both their destructive and constructive leadership

Untwisting of a cholesteric elastomer by a mechanical field

A mechanical strain field applied to a monodomain cholesteric elastomer will unwind the helical director distribution. There is an analogy with the classical problem of an electric field applied to a cholesteric liquid crystal, but with important differences. Frank elasticity is of minor importance unless the gel is very weak. The interplay is between director anchoring to the rubber elastic matrix and the external mechanical field. Stretching perpendicular to the helix axis induces the uniform unwound state via the elimination of sharp, pinned twist walls above a critical strain. Unwinding through conical director states occurs when the elastomer is stretched along the helical axis.Comment: 4 pages, RevTeX 3 style, 3 EPS figure

Stereo-selective swelling of imprinted cholesteric networks

Molecular chirality, and the chiral symmetry breaking of resulting macroscopic phases, can be topologically imprinted and manipulated by crosslinking and swelling of polymer networks. We present a new experimental approach to stereo-specific separation of chiral isomers by using a cholesteric elastomer in which a helical director distribution has been topological imprinted by crosslinking. This makes the material unusual in that is has a strong phase chirality, but no molecular chirality at all; we study the nature and parameters controlling the twist-untwist transition. Adding a racemic mixture to the imprinted network results in selective swelling by only the component of ``correct'' handedness. We investigate the capacity of demixing in a racemic environment, which depends on network parameters and the underlying nematic order

True optical spacial derivatives for plasma density measurements

This paper shows analytically and numerically that a vortex plate coupled to a neutral density filter can deliver a true optical derivative when placed at the focal plane of a $2f$ lens pair. This technique turns spatial variations in intensity into an intensity, which square root is the spatial derivative of the initial intensity variation. More surprisingly, it also turns any spatial variations in phase into an intensity, which square root is the spatial derivative of the initial phase variation. Since the optical derivative drops the DC component of the signal, it is possible to measure the full electron plasma turbulence spectrum optically, without using any interferometer

Measuring empathy in schizophrenia:The Empathic Accuracy Task and its correlation with other empathy measures

Introduction: Empathy is an interpersonal process impaired in schizophrenia. Past studies have mainly used questionnaires or performance-based tasks with static cues to measure cognitive and affective empathy. We used the Empathic Accuracy Task (EAT) designed to capture dynamic aspects of empathy by using videoclips in which perceivers continuously judge emotionally charged stories. We compared individuals with schizophrenia with a healthy comparison group and assessed correlations among EAT and three other commonly used empathy measures. Method: Patients (n = 92) and a healthy comparison group (n = 42) matched for age, gender and education completed the EAT, the Interpersonal Reactivity Index, Questionnaire of Cognitive and Affective Empathy and Faux Pas. Differences between groups were analyzed and correlations were calculated between empathy measurement instruments. Results: The groups differed in EAT performance, with the comparison group outperforming patients. A moderating effect was found for emotional expressivity of the target: while both patients and the comparison group scored low when judging targets with low expressivity, the comparison group performed better than patients with more expressive targets. Though there were also group differences on the empathy questionnaires, EAT performance did not correlate with questionnaire scores. Conclusions: Individuals with schizophrenia benefit less from the emotional expressivity of other people than the comparison group, which contributes to their impaired empathic accuracy. The lack of correlation between the EAT and the questionnaires suggests a distinction between self-report empathy and actual empathy performance. To explore empathic difficulties in real life, it is important to use instruments that take the interpersonal perspective into account. (C) 2019 Published by Elsevier B.V

Developing standards for reporting implementation studies of complex interventions (StaRI): a systematic review and e-Delphi

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited

Measuring academic research impact: creating a citation profile using the conceptual framework for implementation fidelity as a case study

The “citation score” remains the most commonly-used measure of academic impact, but is also viewed as practically and conceptually limited. The aim of this case study was to test the feasibility of creating a “citation profile” for a single, frequently-cited methods paper, the author’s own publication on the conceptual framework for implementation fidelity. This was a proof-of-concept study that involved an analysis of the citations of a single publication. This analysis involved identifying all citing publications and recording, not only how many times the key paper was cited within each citing publication, but also within which sections of that publication (e.g. Background, Methods, Results etc.). Level of impact could be categorised as high, moderate or low. The key paper had been cited more than 400 times and had a high impact in 25 % of publications based on citation frequency within publications, i.e. the key paper was cited three or more times; and a low impact in 58 % of citing publications, i.e. the key paper was cited just once. There were 41 “high impact” publications based on location of the citations, of which 35 (85 %) were also categorised as high impact by frequency. These results suggest that it is both possible and straightforward to categorise the level of impact of a key paper based on its “citation profile”, i.e., the frequency with which the paper is cited within citing publications, thus adding depth and value to the citation metric