Coping with disturbances

Motion systems must cope with internal and external disturbances affecting the envisioned movement program. In science responses to disturbances are used to characterize system properties. Recently, evidence has been collected that self-stability due to the mechanical response of a system can greatly contribute to safe guarding proper operation of the system and to follow up an envisioned task. Here we review research in our laboratory on the kinematic response of standing subjects to sudden pulls inflicted by a motor, and the kinetics of runners crossing a track with a bump. We find that in both cases the first responses are dominated by system compliance. Thereby damage is avoided and the tasks are secured. Preparation to the observed disturbance does not seem to have the goal to compensate quickly but to enhance the scope of the reaction and its economy.     

Exploration of Predictors of Teaching Effectiveness: The Professor’s Perspective

This research is an exploratory investigation of what attributions college professors place upon the cause of teaching effectiveness and success. Student evaluations of teaching are used as a proxy for teaching effectiveness. The study is supported by Attribution Theory in that perceptions and attributions of causality affect motivation and success. The research evaluates data that supported Attribution Theory. The data was collected using Qualtrics through a web-based survey. Partial least squares structural equation modeling was used to evaluate the survey data, with interesting conclusions. The most interesting difference was that between the perceptions of causal attribution of tenured and non-tenured professors. The data show that tenured professors attribute teaching effectiveness to factors outside their control such as characteristics of the students and the institution, while non-tenured professors do not attribute teaching effectiveness to external factors. The implications of this study are support for Attribution Theory in the college teaching context, and may be useful for university administration in motivating professors for effective teaching. Future research includes deductive study to further explore the scope and boundary conditions of Attribution Theory in college teaching.     

The influence of red on impression formation in a job application context

Recent research has shown that the color red can influence psychological functioning. In the present research we tested the hypothesis that red influences impression formation related to another person’s abilities. We conducted three experiments examining the influence of red on the evaluation of male target persons. In Experiment 1, participants viewing red, relative to green, on the shirt of a person presented on a photograph perceived him to be less intelligent. This effect was strongest in a job application context compared to other contexts. In Experiment 2, focusing solely on the job application context, participants viewing red, relative to blue, on an applicants’ tie perceived him to have less earning and leadership potential. In Experiment 3, participants viewing red, relative to green, on a job applicants’ tie rated him as less likely to be hired, and perceptions of ability and leadership potential mediated this effect. Both the conceptual and applied implications of these findings are discussed.     

The two sides of goal intentions: Intention self-concordance and intention strength as predictors of physical activity

Objective: The present research introduces an extended conceptualisation of self-concordance, which is considered an attribute not only of goals, but also of goal intentions. Based on a corresponding operationalisation, we investigate the interplay of both intention strength and intention self-concordance in the prediction of physical activity.

Design: Data were taken from a longitudinal study of 134 obese people who were asked to fill out a questionnaire three times every six months.

Main measures: Physical activity and intention self-concordance were measured by validated scales. Intentions strength was assessed by an item typically employed in the extant literature.

Results: Logistic regression analyses and path analyses showed both intention strength and self-concordance to be significant predictors of changes in physical activity over time. Additional analyses found self-efficacy to be a significant predictor of intention strength and self-concordance; for outcome expectations this was not the case.

Conclusions: Findings support the idea that intention strength and self-concordance are two critical facets of a goal intention that need to be considered in the prediction of physical activity participation. Whereas intention strength refers to the degree of determination with which a goal intention is adopted, self-concordance rather captures the quality of this intention.     

Repetition of educational AIDS advertising affects attitudes

In educational AIDS campaigns, initiators often use advertisements to warn about the threat of AIDS. The present Internet study (N = 283) tested the assumption of an inverted U-shaped relationship between the number of educational AIDS advertisements in a magazine and the perceived threat of AIDS among different groups (i.e., homosexual men and heterosexual men and women). This expectation was primarily based on signaling theory, which assumes that recipients use repetition frequency as a cue for judgments about the message. Results provided support for the expected inverted U-curve.     

Vortex re-capturing and kinematics in human underwater undulatory swimming

To maximize swimming speed athletes copy fish undulatory swimming during the underwater period after start and turn. The anatomical limitations may lead to deviations and may enforce compensating strategies. This has been investigated by analyzing the kinematics of two national female swimmers while swimming in a still water pool. Additionally, the flow around and behind the swimmers was measured with the aid of time-resolved particle image velocimetry (TR-2D-PIV). As compared to fish, the swimmers used undulatory waves characterized by much higher Strouhal numbers but very similar amplitude distributions along the body and Froude efficiencies. Vortices generated in the region of strongly flexing joints are suitable to be used pedally to enhance propulsion (vortex re-capturing). Complementing studies using numerical and technical modeling will help us to probe the efficiency of observed mechanisms and further improvements of the human strategy.     

Die DPG-Praxis-Studie

All psychotherapeutic methods must be scientifically evaluated. Empirical evaluation of evidence is a prerequisite for acceptance as scientific psychotherapy as well as for payment by health insurance. Currently the psychotherapy methods accepted within the German health system (behavioural therapy, psychodynamic psychotherapy, and analytic psychotherapy) are reviewed by a governmental evaluation committee concerning evidence, necessity and cost-effectiveness. The DPG practice study has basically two aims: 1) to conduct a large naturalistic study to investigate effectiveness, sustainability and economic aspects of psychodynamic and analytic psychotherapy and 2) to offer a framework for psychoanalytic institutes, members, candidates or groups to realize own research ideas by collecting additional data within the study. The present article describes the background, main research questions, structure and design of the DPG practice study with regard to the evaluation questions.