Lehrkrafteinstellungen und -motivation als Mediatoren zwischen Ausbildungsqualität, Kooperation und Differenzierung im Unterricht

Heterogeneity in achievement characterizes many classrooms. Teachers can adapt to students’ varying achievement levels by engaging in differentiated instruction (DI). Applying this strategy adequately is influenced by perceived teacher training quality and collaboration. The current study examined the dimensional structure and predictors of DI as well as a mediation of both teachers’ attitudes and motivation. Confirmatory factor analysis confirmed a three-dimensional structure of DI. Teacher training and collaboration were proved to be predictors of DI. Expected success as a measure of motivation was confirmed as a mediator of perceived quality of teacher training on DI, but not the two attitude aspects perceived utility and costs. The relevance of the findings for teacher education and school as a workplace is discussed. (DIPF/Orig.)Leistungsheterogenität findet sich in vielen Schulklassen. Durch Differenzierung (DI) können Lehrkräfte auf die verschiedenen Leistungsniveaus eingehen, wobei der Einsatz dieser Strategie von wahrgenommener Ausbildungsqualität und Kooperation beeinflusst wird. Die vorliegende Studie untersuchte sowohl die Struktur und Prädiktoren von DI als auch Mediationseffekte durch Lehrkrafteinstellungen und -motivation. Konfirmatorische Faktorenanalysen bestätigten eine dreidimensionale Struktur von DI sowie die Ausbildungsqualität und Kooperation als Prädiktoren. Der erwartete Erfolg als ein Maß von Motivation wurde als Mediator zwischen wahrgenommener Ausbildungsqualität und DI von den Daten gestützt, allerdings nicht die Einstellungsaspekte wahrgenommene Nützlichkeit und Kosten. Die Relevanz der Ergebnisse für Lehrkraftausbildung und den Arbeitsplatz Schule wird diskutiert. (DIPF/Orig.

Dissolution and transformation of cerium oxide nanoparticles in plant growth media

From environmental modeling of engineered nanomaterial (ENM) release, it is clear that ENMs will enter soils, where they interact with soil compounds as well as plant roots. We analyzed three different size groups of cerium dioxide nanoparticles (CeO2-NPs) in respect to chemical changes in the most common plant growth medium, Hoagland solution. We created a simple environmental model using liquid dispersions of 9-, 23-, and 64-nm-uncoated CeO2-NPs. We found that CeO2-NPs release dissolved Ce when the pH of the medium is below 4.6 and in the presence of strong chelating agents even at pH of 8. In addition, we found that in reaction with Fe2+-ions, equimolar amounts of Ce were released from NPs. We could elucidate the involvement of the CeO2-NPs surface redox cycle between Ce3+ and Ce4+ to explain particle transformation. The chemical transformation of CeO2-NPs was summarized in four probable reactions: dissolution, surface reduction, complexation, and precipitation on the NP surface. The results show that CeO2-NPs are clearly not insoluble as often stated but can release significant amounts of Ce depending on the composition of the surrounding medium

Geschlechtsunterschiede im Lesen an digitalen Geräten? Analysen zur Rolle von Motivation und Selbstkonzept

Reading is a core prerequisite for educational success and participation in society. However, comprehensive empirical research is needed to understand how reading may differ in a digitalized world. The current study addressed the gender gap in reading digitally. It investigated competence scores along with information on (a) reading and (b) digital motivation and self-concept in 588 elementary school students. Results revealed a gender gap in reading digitally, in reading motivation and self-concept, and in motivation and self-concept in respect to working on digital devices. Only reading motivation variables predicted reading digitally, thereby providing important information on the validity of digitally based reading tests. Reading motivation was found to fully mediate the gender effect on reading digitally. Results have important implications for research and practice. (DIPF/Orig.)Lesen ist eine zentrale Voraussetzung für Bildungserfolg und gesellschaftliche Teilhabe. Wegen der fundamentalen Bedeutung des Lesens sind umfassende empirische Erkenntnisse zu der Frage, wie sich das Lesekonstrukt im Zuge der Digitalisierung verändert, notwendig. Vor diesem Hintergrund analysierte die vorliegende Studie Geschlechtsunterschiede im Lesen an digitalen Geräten. Neben Lesekompetenzen an digitalen Geräten wurden intrinsische Motivation und Selbstkonzepte in den Bereichen (a) Lesen und (b) Arbeit an digitalen Geräten von 588 Grundschulkindern betrachtet. Mädchen und Jungen unterschieden sich in der Lesekompetenz, in lesebezogener Motivation und Selbstkonzept sowie in Motivation und Selbstkonzept zur Arbeit an digitalen Geräten. Ausschließlich lese bezogene motivationale Merkmale sagten die Lesekompetenz vorher, was auf die Validität des Lesetests hinwies. Außerdem mediierte die intrinsische Lesemotivation die Geschlechtsunterschiede in der Lesekompetenz vollständig. Die Ergebnisse haben wichtige Implikationen für Bildungsforschung und -praxis. (DIPF/Orig.

Positive social relationships with peers and teachers as moderators of the Big-Fish-Little-Pond Effect

Students' academic self-concepts (ASCs) are largely formed relative to the ability of their reference group. The Big-Fish-Little-Pond Effect (BFLPE), according to which equally able students have lower ASCs in high-achieving classrooms than in low-achieving ones, is extremely robust. Social relationships are known to be important for self-perception. This study aims at analyzing social relationships as potential moderators of the BFLPE, focusing on two core partners in classrooms: peers and teachers. Multilevel structural equation modeling was applied to test the moderator hypotheses, drawing on data from a sample of N = 7004 secondary school students. Whereas no support was found for a moderating effect of peer relationships, data supported the assumed moderation of the BFLPE through student-teacher relationships. Students with positive teacher relations experienced smaller BFLPEs than students with negative or average teacher relations. The study illustrates how relationships moderate frame of reference effects that are central to the formation of ASCs

Inclusive learning environments. The attitudes and motivation of teachers

Eine Gelingensbedingung für erfolgreiches Lehren und Lernen in heterogenen Schulklassen sind die Einstellungen und Motivation der Lehrkräfte. Die vorliegende Studie untersuchte Struktur, Ausprägung und Prädiktoren von Einstellungen und Motivation von Lehrkräften gegenüber einer inklusionsbedingt heterogenen Schülerschaft. Anhand einer Befragung von N = 203 Lehrkräften weiterführender Schulen wurde erstens gezeigt, dass die fünf angenommenen Facetten trennbar waren. Zweitens ergaben die Analysen, dass Einstellungen und Motivation der Lehrkräfte insgesamt im Mittel leicht positiv ausgeprägt waren, aber auch hohe Kosten gesehen wurden. Drittens wurden Geschlecht, Profession, Lehrerfahrung und Fortbildungsbesuch als relevante Prädiktoren für Einstellungen und Motivation identifiziert. (DIPF/Orig.)Teachers’ attitudes and motivation are a main factor of influence for successful teaching and learning. Against this background the following study analysed the structure, manifestations, and predictors of teachers’ attitudes and motivation towards groups of learners who are heterogeneous because of inclusion. Drawing on data of N = 203 secondary school teachers, the analysis revealed firstly, that the five expected constructs were empirically separated, but interrelated. Secondly, manifestations of attitudes and motivation were slightly positive, but high values of costs were also observed. Thirdly, gender, profession, teaching experience, and training attendance were all important predictors of attitudes and motivation. (DIPF/Orig.

Dissolution and transformation of cerium oxide nanoparticles in plant growth media

From environmental modeling of engineered nanomaterial (ENM) release, it is clear that ENMs will enter soils, where they interact with soil compounds as well as plant roots. We analyzed three different size groups of cerium dioxide nanoparticles (CeO2-NPs) in respect to chemical changes in the most common plant growth medium, Hoagland solution. We created a simple environmental model using liquid dispersions of 9-, 23-, and 64-nm-uncoated CeO2-NPs. We found that CeO2-NPs release dissolved Ce when the pH of the medium is below 4.6 and in the presence of strong chelating agents even at pH of 8. In addition, we found that in reaction with Fe2+-ions, equimolar amounts of Ce were released from NPs. We could elucidate the involvement of the CeO2-NPs surface redox cycle between Ce3+ and Ce4+ to explain particle transformation. The chemical transformation of CeO2-NPs was summarized in four probable reactions: dissolution, surface reduction, complexation, and precipitation on the NP surface. The results show that CeO2-NPs are clearly not insoluble as often stated but can release significant amounts of Ce depending on the composition of the surrounding medium.ISSN:1388-0764ISSN:1572-896

Abyssal Solenogastres (Mollusca, Aplacophora) from the Northwest Pacific: Scratching the Surface of Deep-Sea Diversity Using Integrative Taxonomy

Solenogastres (Aplacophora) is a small clade of marine, shell-less worm-molluscs with close to 300 valid species. Their distribution ranges across all oceans, and whereas the vast majority of species has been collected and described from the continental shelf and slope, only few species are known from depths below 4,000 m. Following traditional taxonomy, identification of specimens to species level is complex and time-consuming and requires detailed investigations of morphology and anatomy—often resulting in the exclusion of the clade in biodiversity or biogeographic studies. During the KuramBio expedition (Kuril-Kamchatka Biodiversity Studies) to the abyssal plain of the Northwest Pacific and the Kuril-Kamchatka Trench, 33 solenogaster specimens were sampled from 4,830 m to 5,397 m. Within this study we present an efficient workflow to address solenogaster diversity, even when confronted with a high degree of singletons and minute body sizes, hampering the use of single individuals for multiple morphological and molecular approaches. We combine analyses of external characters and scleritome with molecular barcoding based on a self-designed solenogaster specific set of mitochondrial primers. Overall we were able to delineate at least 19 solenogaster lineages and identify 15 species to family level and beyond. Based on our approach we identified three key lineages from the two regionally most species-rich families (Acanthomeniidae and Pruvotinidae) for deeper taxonomic investigations and describe the novel abyssal species Amboherpia abyssokurilensis sp. nov. (Cavibelonia, Acanthomeniidae) using microanatomical 3D-reconstructions. Our study more than doubles the previous records of solenogaster species from the Northwest Pacific and its marginal seas. Almost all lineages are reported for the first time from the region of the (Northwest) Pacific, vastly expanding distribution ranges of the respective clades. Moreover it doubles the number of Solenogastres collected from abyssal depths on a global scale and underlines the lack of exploratory α-diversity work in the abyssal zone for reliable species estimates in marine biodiversity