Resampling and Distribution of the Product Methods for Testing Indirect Effects in Complex Models

Recent advances in testing mediation have found that certain resampling methods and tests based on the mathematical distribution of 2 normal random variables substantially outperform the traditional z test. However, these studies have primarily focused only on models with a single mediator and 2 component paths. To address this limitation, a simulation was conducted to evaluate these alternative methods in a more complex path model with multiple mediators and indirect paths with 2 and 3 paths. Methods for testing contrasts of 2 effects were evaluated also. The simulation included 1 exogenous independent variable, 3 mediators and 2 outcomes and varied sample size, number of paths in the mediated effects, test used to evaluate effects, effect sizes for each path, and the value of the contrast. Confidence intervals were used to evaluate the power and Type I error rate of each method, and were examined for coverage and bias. The bias-corrected bootstrap had the least biased confidence intervals, greatest power to detect nonzero effects and contrasts, and the most accurate overall Type I error. All tests had less power to detect 3-path effects and more inaccurate Type I error compared to 2-path effects. Confidence intervals were biased for mediated effects, as found in previous studies. Results for contrasts did not vary greatly by test, although resampling approaches had somewhat greater power and might be preferable because of ease of use and flexibility.     

Relationships Among Cortical Thickness,Reading Skill,and Print Exposure in Adults

This study investigated relationships among cortical thickness in the left-hemisphere reading network, and reading skill and experience in adult nonimpaired readers. Given the relationship between print exposure and reading, it is possible that print exposure is related to cortical structure. The pattern of correlations indicated that individuals with higher print exposure had better reading skills and thicker cortices. Furthermore, print exposure accounted for unique variance in cortical thickness in part of the left-hemisphere reading network after accounting for reading skill. This suggests that some of the variation in cortical thickness in adults might be attributable to reading experience, independently of reading skill.     

Using the I² Intervention Matrix to Select the Best Course of Action

The I² intervention selection matrix is a useful tool that will help in the selection of appropriate interventions based on the level of impact and invasiveness of the intervention. It is a two‐axis grid that places interventions in one of four quadrants. Based on which quadrant the intervention falls in, a practitioner can decide which interventions to use, not use, or use with caution. It is a simple yet elegant way to determine appropriateness.     

Islands of Detroit: Affect,Nostalgia and Whiteness

Abstract

‘Islands of Detroit’ explores the possibilities for an ‘everyday, oppositional whiteness’, a thoughtful randomness, as a corrective to ‘reactionary’ and ‘evasive’ forms of whiteness which often embed themselves in populist media sites for nostalgia. Drawing on the theoretical work of Svetlana Boym, Uday Singh Mehta and Roland Barthes, this essay looks in particular at a coffee table book, The Way it Was (2004 Bulanda, G., ed. 2004. The Way It Was: Glimpses of Detroit’s History from the Pages of Hour Detroit Magazine, Royal Oak, MI: Momentum.  [Google Scholar]), and its generic sentimentalism, to understand how certain white visual representations of Detroit affectively generate nostalgia, which can in turn conceal pasts and racial tensions. Looking at the history of Detroit (with particular attention on how the two infamous race riots are and are not negotiated), Islands examines visual images of the city – as opposed to the city itself – through the discursive lenses of nostalgia, modernity and affect, while positing that the histories and identities of Detroit remain irreducible to the images which attempt to capture them.     

Extended-state-observer-based output feedback adaptive control of hydraulic system with continuous friction compensation

This paper presents an extended state observer-based output feedback adaptive controller with a continuous LuGre friction compensation for a hydraulic servo control system. A continuous approximation of the LuGre friction model is employed, which preserves the main physical characteristics of the original model without increasing the complexity of the system stability analysis. By this way, continuous friction compensation is used to eliminate the majority of nonlinear dynamics in hydraulic servo system. Besides, with the development of a new parameter adaption law, the problems of parametric uncertainties are overcome so that more accurate friction compensation is realized. For another, the developed adaption law is driven by tracking errors and observation errors simultaneously. Thus, the burden of extended state observer to solve the remaining uncertainties is alleviated greatly and high gain feedback is avoided, which means better tracking performance and robustness are achieved. The designed controller handles not only matched uncertainties but also unmatched dynamics with requiring little system information, more importantly, it is based on output feedback method, in other words, the synthesized controller only relies on input signal and position output signal of the system, which greatly reduces the effects caused by signal pollution, measurement noise and other unexpected dynamics. Lyapunov-based analysis has proved this strategy presents a prescribed tracking transient performance and final tracking accuracy while obtaining asymptotic tracking performance in the presence of parametric uncertainties only. Finally, comparative experiments are conducted on a hydraulic servo platform to verify the high tracking performance of the proposed control strategy.     

Mediating a compromised solidarity

ABSTRACT

This article explores popular media as resources for judgment in how settled migrants in Europe imagine solidarities toward newer arrivals seeking entry into the region. It discusses the news and entertainment consumption of Filipino nurses in London and how this figures in their imaginary of social and political bonds with refugees. Drawing on ethnographic interviews, I argue that these Filipino migrants can only articulate a compromised solidarity: one fractured between empathy with refugees and concern about what these newer arrivals might mean for settled migrants in the city. I then explain how the media contribute to this fracturing. One way is that the xenophobia in popular media content on social media leads the Filipinos to assert their difference with other migrants, including refugees. A second is that the Filipinos deploy popular media content, especially on British television, to assert that they belong to UK society more than other migrants, again including refugees.     

Courting Apocalypse: Creating a Zombie-Themed Evidence-Based Medicine Game

In 2015, two librarians at the Hardin Library for the Health Sciences at the University of Iowa turned their dreams into a reality and secured funding to build a zombie-themed evidence-based medicine game. The game features a “choose your own adventure” style that takes students through a scenario where a disease outbreak is taking place and a resident is asked to use evidence-based medicine skills to select a screening and diagnostic tool to use on potentially infected patients. Feedback on the game has been positive, and future plans include building additional modules on therapy, harm, and prognosis.