On the growth of structural equation modeling in psychological journals

This study investigates the distribution of technical and substantive structural equation modeling articles (SEM) that were published in psychological journals from 1987 to 1994. An inspection of more than 1050 abstracts on PsycLit 1987–1995 (PsycINFO, 1973–1995) revealed a number of clear trends: (a) an increase by year of articles concerned with SEM, (b) an increase in the number of journals that publish structural equation modeling articles, (c) a relatively stable output of technical articles across years, and (d) an increase of substantive articles across years. Furthermore, when the substantive articles are classified as either causal models or confirmatory factor analyses, a similar “growth” trend across years occurs for both categories. We further inspected the growth trend by considering the ratio of SEM articles to the total number of psychology articles and by comparing these results to distributions of analysis of variance, multivariate analysis of variance, regression, and factor analyses articles for the period of 1973 to 1994.     

A match between university professors and school inspectors? Innovation and stagnation in the physical education curriculum

During the 1960s and 1970s, “traditional” secondary educational systems in various Western European countries made way for comprehensive education curricula. In contrast to the reforms within the “intellectual” subjects, the field of physical education (PE) remained largely underexposed in research. This study focuses on PE reform in Belgium, the first country in the world (apart from Sweden itself) to introduce, in 1908, so-called “Swedish gymnastics” in all levels of state public education and, in 1968, the last country apart from Portugal to abandon it. The question arises as to who was responsible for Swedish gymnastics being applied for so long and, ultimately, how and by whom reform was implemented. The results show that the power of the past and the positions of “Swedists” in the Government Inspectorate, universities and professional associations, perpetuated the domination of Swedish gymnastics in Belgian education. The final “dynamisation” of the subject of PE around 1968 did not come about through “revolution” but a “natural” generational transition, whereby a new guard of young government inspectors with a drive for reform took over from their Swedish-minded predecessors. The educational climate prevailing in Belgium at the end of the 1960s facilitated this reform. The state university PE institutes lost their position as pedagogical profile keepers during this process of transformation, while the hidden curriculum of the (Catholic) university institute in Leuven implicitly shaped the educational climate. Further comparative international research into the (changed) profile, position and power of school inspectors in educational reform appears necessary.     

Single cell rheometry with a microfluidic constriction: Quantitative control of friction and fluid leaks between cell and channel walls

We report how cell rheology measurements can be performed by monitoring the deformation of a cell in a microfluidic constriction, provided that friction and fluid leaks effects between the cell and the walls of the microchannels are correctly taken into account. Indeed, the mismatch between the rounded shapes of cells and the angular cross-section of standard microfluidic channels hampers efficient obstruction of the channel by an incoming cell. Moreover, friction forces between a cell and channels walls have never been characterized. Both effects impede a quantitative determination of forces experienced by cells in a constriction. Our study is based on a new microfluidic device composed of two successive constrictions, combined with optical interference microscopy measurements to characterize the contact zone between the cell and the walls of the channel. A cell squeezed in a first constriction obstructs most of the channel cross-section, which strongly limits leaks around cells. The rheological properties of the cell are subsequently probed during its entry in a second narrower constriction. The pressure force is determined from the pressure drop across the device, the cell velocity, and the width of the gutters formed between the cell and the corners of the channel. The additional friction force, which has never been analyzed for moving and constrained cells before, is found to involve both hydrodynamic lubrication and surface forces. This friction results in the existence of a threshold for moving the cells and leads to a non-linear behavior at low velocity. The friction force can nevertheless be assessed in the linear regime. Finally, an apparent viscosity of single cells can be estimated from a numerical prediction of the viscous dissipation induced by a small step in the channel. A preliminary application of our method yields an apparent loss modulus on the order of 100 Pa s for leukocytes THP-1 cells, in agreement with the literature data.     

Conceptualizing a Spatial Data Infrastructure for the Social Sciences: An Example from Germany

There is an increasing demand for spatial data within the social sciences as such data promise to contribute to a better understanding of how the concrete living environment influences individuals’ attitudes and behaviors. Spatial data can complement data from surveys; however, as of yet there is no spatial data infrastructure for the social sciences in Germany that facilitates merging of spatial data with survey data. This article explores avenues for creating such a spatial data infrastructure (SDI) for the social sciences in Germany. We examine the role that librarians, archivists, and curators can play in offering spatial data infrastructure services for social scientists, and show the scope and nature of necessary tasks in areas such as harmonization, archiving, dissemination, and user support. As the case of Germany is similar to that of other European countries, we expect our results to be helpful in the creation of SDIs in other countries as well. This article suggests technical and organizational measures for merging survey data and spatial data in compliance with German privacy legislation. Measures for storage and dissemination of enriched survey data, for example by providing restricted access to the data in a secured environment, also are explored.     

Fostering effective studying and study planning with study questions

In a course on biological psychology and neuropsychology, study questions were provided that also appeared as test questions in the course exam. This method was introduced to support students in active processing and reproduction of the study texts, and study planning. Data were gathered to test the hypothesis that study question use would be beneficial to course grades. In addition, the way in which students evaluated the method was studied. It appeared that the number of study questions answered prior to the exam had a positive effect on course grades. Students were generally positive about the use of the questions in terms of their study planning.     

Linkages Between Children's and Their Friends' Social and Physical Aggression: Evidence for a Gene–Environment Interaction?

Based on a sample of 406 seven-year-old twins, this study examined whether exposure to friends' social or physical aggression, respectively, moderates the effect of heritability on children's own social and physical aggression. Univariate analyses showed that children's own social and physical aggression were significantly explained by genetic factors, whereas friends' social and physical aggression represented "true" environmental factors that were unrelated to children's genetic dispositions. Multivariate analyses further suggested a possible gene–environment interaction in the link between friends' and children's physical aggression but not in the link between friends' and children's social aggression. Instead, friends' social aggression was directly related to children's social aggression, in addition to genetic effects on this behavior. Theoretical and practical implications of these results are discussed.     

Achievement of first-year students at the university: a multilevel analysis of the role of background diversity and student engagement

European Journal of Psychology of Education - The massification and diversification of the student population who enters university has become a challenge for Higher Education institutions. A...