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Laser cutting is used in the production of formed sheet metal components. However, the cyclic load capacity is reduced compared to other subtractive processes. Laser cutting results in a significant loss of fatigue strength; however, thermal joining has its own effect on the cyclic load capacity. Accordingly, brazing causes a significant reduction in the mechanical strength. However, the open question is what consequences a combination of both processes may have on the overall fatigue strength of sheet metals. Laser-cut samples of AISI 304 with and without a brazed-on element were investigated for their microstructure and mechanical properties. The brazing process was found to have an annealing effect on the microstructure. It was further observed that the fatigue behavior of brazed specimens is dominated by inhomogeneities at the surface of the filler metal fillet located in the geometric notch of the brazed joint. Fatigue strength decreased by almost 50% compared to as-cut specimens. As long as no shared diffusion zone is formed between the laser-cut and the brazed joint, the use of laser cutting for the production of such components appears to be reasonable and does not further contribute to the loss of cyclic strength.

Social robots and the Internet of Toys represent key technologies in children’s future lives. Based on Winfield (Robotics: A Very Short Introduction. Oxford University Press, Oxford, 2012), we conceptualize the relationship between social robots and smart/connected toys with six characteristics: interactivity, energy, sensors, software control, movement and embodiment. These characteristics, in turn, help to classify social robots and smart/connected toys along three dimensions (i.e. horizontal, vertical and spatial integration), which suggests that the difference between social robots and smart/connected is rather subtle. We identify three common theoretical (absence or heterogeneity of theory, lacking developmental perspective, insufficient attention to intercultural differences) and three methodological issues (lack of standardized measures, study design issues, dominance of cross-sectional studies) that research on both social robots and the Internet of Toys needs to address.

This chapter introduces the notion of “news unbundling”, the phenomenon that in today’s online media landscape, news items are distributed separately. In contrast to newspaper articles that were bundled in one newspaper edition, items from very different sources are distributed via various channels. Thus, the same item can arrive at the user via different pathways, including news sites, news aggregators, and social media. Therefore, the chapter proposes to conceptualize and measure (online) news exposure as a network of users and news items. The proposed model allows to for integrative research perspectives by seeing channel and brand as properties of edges and nodes, while putting the news item itself in a central role, allowing to test communication theory in an unbundled news ecosystem. It allows to answer flow-of-information questions such as via which route a given piece of information reaches a recipient and how this can be predicted; or to test online agenda-setting effects.

In den letzten Jahrzehnten ist das kommunikationswissenschaftliche Interesse an Emotionen stark angestiegen (Wirth, 2008, 2014a). Allerdings bleiben die empirische Erfassung von Emotionen in Kommunikationsinhalten sowie die Forschung zu deren Wirkung hinter der aktuellen Theoriebildung zuruck. Dies kann zu Missverstandnissen in Bezug auf die Verbreitung von emotionalen Kommunikations-inhalten und deren Wirkungen fuhren.

There has been an increasing amount of attention in the literature for sexualization in the media. Sexualization occurs when “a person’s value comes only from his or her sexual appeal or behavior, to the exclusion of other characteristics; a person is held to a standard that equates physical attractiveness (narrowly defined) with being sexy; a person is sexually objectified—that is, made into a thing for others’ sexual use, rather than seen as a person with the capacity for independent action and decision making; and/or sexuality is inappropriately imposed upon a person”. Recently, scholars have started to pay attention to how sexualization may occur in social media, where adolescents are said to self-sexualize through posting sexy pictures of themselves (sexy self-presentation). Based on an overview of recent research on adolescents’ social media use and online self-presentation, it can be concluded that some aspects of sexualization, such as self-objectification and the increased emphasis on physical and sexual attractiveness, also occur in social media. However, we still lack knowledge on other aspects of online (self-)sexualization, such as the occurrence of sexual objectification and whether sexual content is inappropriately imposed upon adolescents in social media. Moreover, although there is initial evidence that the use of social media decreases self-esteem and sexual satisfaction, we still lack knowledge on whether the same consequences that are said to occur for sexualization in traditional media also occur for self-sexualization in social media. Suggestions for future research on (self-)sexualization in social media are given, which also pertain to the unique aspects of social media (i.e., peer norms and self-perception) compared to traditional media platforms.

Be it television, mobile phones or social networking sites – media technologies and applications form a substantial part of young people’s lives. It is significant that media use is one of the most prevalent daily activities during a period of life in which crucial developmental goals are pursued: During adolescence and young adulthood individuals strive to establish critical social relationships, achieve autonomy from their parents and develop a stable identity. Bearing all this in mind, this volume provides a collection of articles on the uses and effects of media among young people, and the developmental context within which these relationships are embedded. Alongside studies on the determinants of mobile phone use, social networking site use and online behaviour, studies on reality TV and news viewing patterns are included, as is research on the effects of social media use, advertising, product placements and public service announcements.

The general linear model, which incorporates statistical analyses, such as ordinary least squares regression, t‐test, and analysis of variance, is based on a series of assumptions about the independent variables, the dependent variable, and the error terms. Because these assumptions are often violated in the analysis of categorical data, alternative techniques should be employed. This entry reviews regression models which are adequate for the analysis of categorical dependent variables.

Communication researchers regularly conduct comparisons between populations and comparisons over time. Typically, the objects of a comparison are relationships between constructs, such as media effects, or the means of constructs, such as average media use. Importantly, comparisons of relationships and means are based on the assumption that the involved constructs are measured the same way across populations or over time. If this assumption holds, the measurements are invariant across populations or over time. However, most comparative studies do not explicitly test for measurement invariance. This is problematic because results of comparisons can be biased when invariance assumptions are violated. Measurement invariance must thus be tested in all comparative communication studies. This entry discusses the different forms of measurement invariance for continuous data and how they can be tested in multigroup confirmatory factor analyses. Furthermore, partial measurement invariance, and invariance tests for ordinal data and for formative measurement models are discussed.

We performed a prospective randomized study to determine blood loss differences between supine or lateral patient position, during surgery in elective total hip replacement. Between January and October 1996, 64 consecutive cases of total hip replacements were randomly scheduled for a procedure either in the supine or in the lateral position. Of the 56 cases evaluated, 29 were operated in the supine position (SP) and 27 in the lateral position (LP). The standardized implantations were performed without cement and the blood loss was measured. The calculated loss of Hb on the day of operation was 235 g Hb +/- 17 (mean +/- s.e.) in the SP group and 177 g Hb +/- 14 in the LP group, respectively, (unpaired t-test p = 0.01). The calculated loss of Hb after five postoperative days was 227 g Hb +/- 24 (mean +/- s.e.) in the SP group and 179 g Hb +/- 24 in the LP group, respectively, p < 0.2. The net loss of Hb after five postoperative days was calculated by subtracting all perioperative blood substitutions (Cellsaver, autologous and homologous blood) resulting in 340 g Hb +/- 21 (mean +/- s.e.) in the SP group and 272 g Hb +/- 21 in the LP group, respectively, p = 0.02. The blood loss in primary cementless total hip replacement surgery can be significantly reduced by performing the procedure in the lateral position compared to that in the supine position. The blood loss is limited to the day of operation, as indicated by the stable Hb-levels thereafter.