Faktoren der Veränderung des Selbst bei computervermittelter Kommunikation

Computer-mediated communication (CMC) influences the users’ self. Different expectations are currently made towards how the self may arise in an ‘a-social’ setting during the use of modern “Information” and communication technologies. Some of these discourses even observe a new potential for self-constructions. The conceptual frame of the paper is delivered by the combination of different social scientific approaches coming from Social Psychology, Sociology and Communications Studies. Based upon a series of experiments the paper investigates how the social self develops in CMC. Overall the self is moderated by the characteristics of the channel, by psycho-social and finally by socialisation variables. The influence of the channel is marked by immediate effects of certain cues. The psycho-social variable is the individual versus joint usage of CMC. The sociological dimension is the familiarity with CMC. Finally a model is discussed that introduces the prototypical character of CMC for the development of the self in further forms of mediated interpersonal communication.     

The quincunx: history and mathematics

Received: December 30, 1999; revised version: July 19, 2000     

Maximum entropy sampling and optimal Bayesian experimental design

When Shannon entropy is used as a criterion in the optimal design of experiments, advantage can be taken of the classical identity representing the joint entropy of parameters and observations as the sum of the marginal entropy of the observations and the preposterior conditional entropy of the parameters. Following previous work in which this idea was used in spatial sampling, the method is applied to standard parameterized Bayesian optimal experimental design. Under suitable conditions, which include non-linear as well as linear regression models, it is shown in a few steps that maximizing the marginal entropy of the sample is equivalent to minimizing the preposterior entropy, the usual Bayesian criterion, thus avoiding the use of conditional distributions. It is shown using this marginal formulation that under normality assumptions every standard model which has a two-point prior distribution on the parameters gives an optimal design supported on a single point. Other results include a new asymptotic formula which applies as the error variance is large and bounds on support size.     

Expert Study to Select Indicators of the Occurrence of Emerging Mycotoxin Hazards

This article describes a Delphi‐based expert judgment study aimed at the selection of indicators to identify the occurrence of emerging mycotoxin hazards related to Fusarium spp. in wheat supply chains. A panel of 29 experts from 12 European countries followed a holistic approach to evaluate the most important indicators for different chain stages (growth, transport and storage, and processing) and their relative importance. After three e‐mailing rounds, the experts reached consensus on the most important indicators for each of the three stages: wheat growth, transport and storage, and processing. For wheat growth, these indicators include: relative humidity/rainfall, crop rotation, temperature, tillage practice, water activity of the kernels, and crop variety/cultivar. For the transport and storage stage, they include water activity in the kernels, relative humidity, ventilation, temperature, storage capacity, and logistics. For wheat processing, indicators include quality data, fraction of the cereal used, water activity in the kernels, quality management and traceability systems, and carryover of contamination. The indicators selected in this study can be used in an identification system for the occurrence of emerging mycotoxin hazards in wheat supply chains. Such a system can be used by risk managers within governmental (related) organizations and/or the food and feed industry in order to react proactively to the occurrence of these emerging mycotoxins.     

Charisma and organizational change: A multilevel study of perceived charisma,commitment to change,and team performance

What makes people perceive a leader as charismatic, and how do team leaders obtain performance outcomes from their followers? We examine leaders in times of organizational change and investigate the mechanisms through which leaders' change-promoting behaviors are associated with team performance. In a multilevel mediation model, we propose that the indirect relationship between change-promoting behaviors and team performance is sequentially transmitted through followers' perceptions of charisma and followers' commitment to change. A study of 33 leaders and 142 followers provides empirical support for the model, using multilevel structural equation modeling to analyze top-down relationships between leaders and followers and bottom-up relationships between followers and team outcomes. Results suggest that team leaders are perceived as more charismatic when they engage in change-promoting behaviors. These behaviors facilitate team performance through individual followers' perceived charisma and commitment to change.     

The Psychodynamics of Consensual Sadomasochistic and Dominant-Submissive Sexual Games

The author examines a case from a qualitative research study exploring repetition-compulsion and repair in consensual sadomasochistic/dominant-submissive (SMDS) sexual play. The study attempts to bridge the epistemological divide between clinically derived psychoanalytic theories about perversion and nonclinical research on consensual SMDS subcultures. The case addresses research questions about the presence of, and possibilities for, working through childhood developmental conflicts in consensual SMDS (as theoretically differentiated from its nonconsensual counterparts).

This study, along with those theories that uproot classical notions of sexuality and the “oedipal divide,” lends support for the view that the diversity of lived and practiced sexualities defies facile categorization and that, if categorization is to be attempted, it must take into account individual meanings and relational/larger social contexts.     

Living Behind Dikes: Mimicking Flooding Experiences

Delta areas like the Netherlands are threatened by global climate change. Awareness is, however, rather low. Our research objective was to investigate whether coping responses to flooding risks could be enhanced in a virtual environment (VE). A laboratory experiment was conducted in which participants were exposed to a simulated dike breach and consequent flooding of their virtual residence. We tested the hypothesis that an interactive 3D flood simulation facilitates coping responses compared to noninteractive film and slide simulations. Our results showed that information search, the motivation to evacuate, and the motivation to buy flood insurance increased after exposure to the 3D flood simulation compared to the film and slide simulations. Mediation analyses revealed that some of these presentation mode effects were mediated by a greater sense of being present in the VE. Implications to use high‐end flood simulations in a VE to communicate real‐world flooding risks and coping responses to threatened residents will be discussed.     

Nutrient intake in day workers and shift workers

Abstract

The 24-h dietary intake, nutritional status parameters and psychosomatic factors of two-shift, three-shift and day workers were compared. Estimations of the dietary intake (across a work cycle) were made by use of a nutrient database. No significant differences were found between the groups for a large number of nutritional variables: intake of energy; intake and percentage of energy from protein, fat, total carbohydrates and sucrose; intake of coffee; and intake and density of vitamins and minerals. Only minor differences were found between the groups with regard to the quantitative intake of alcohol and calcium, and with regard to the quality of the diet (percentage of energy from alcohol, density of calcium). The groups differed significantly with respect to attitude towards work hours (three-shift workers being most negative in their attitude) and sleep disturbances (shift workers being most negative). The three-shift workers were more evening-oriented and they had higher concentrations of glucose in their blood. It was concluded that work hours not related to nutritional intake—at least not when total amounts across time are considered. It was also concluded that work hours were not related to Body Mass Index or blood lipids: triglycerides, total cholesterol, LDL (low-density lipoprotein) cholesterol and HDL (high-density lipoprotein) cholesterol.