One challenge while learning scientific concepts is to select relevant information and to integrate different representations of the learning content into one coherent mental model. Virtual reality learning environments offer new possibilities to support learners and foster learning processes. Whether learning in VR is successful, however, depends to a large extent on the design of the VRLE and the learners themselves. Hence, adding supportive elements in VRLEs, such as annotations, might facilitate the learning process by guiding attention and supporting the (...) selection of relevant information. Additionally, the mapping of pictorial and verbal information is eased by these annotations. The beneficial effect of annotations is highly dependent on learners' intrinsic motivation as intrinsic motivation while learning also affects the information selection and visual search patterns. In our experimental study, we compared two conditions: learning in a VRLE with or without annotations. We measured the learning outcome on three different levels. Additionally, we investigated intrinsic motivation as a moderator for the effect of annotations on learning outcome. We found no significant main effect of annotations on learning outcome. The moderating effect of intrinsic motivation for annotations on the overall learning outcome was significant. Our results imply that learners are either intrinsically motivated or need additional support by annotations as these support the selection of relevant information in the VRLE and therefore enable them to learn successfully. Which type or quantity of annotations supports learning processes best needs to be explored in future research. (shrink)

The origin and the development of scientific disciplines has been a topic of reflection for several decades. The few extensive case studies support the thesis that scientific disciplines are not monolithic structures but can be characterized by distinct social, organizational and scientific–technical practices. Nonetheless, most disciplinary histories of genetics confine themselves largely to an uncontested account of the content of the discipline or occasionally institutional factors. Little attention is paid to the large number of researchers who, by their joint efforts, (...) ultimately shaped the discipline. We contribute to this aspect of disciplinary historiography by discussing the role of women researchers at the Institute for Heredity Research, founded in 1914 in Berlin under the directorship of Erwin Baur, and the sister of the John Innes Institute at Cambridge. This paper investigates how and why Baur built a highly successful research programme that relied on the efforts of his female staff, whose careers, notably Elisabeth Schiemann's, are also assessedin toto. These women undertook the necessary ‘technoscience’ and in some cases innovative work and helped increase the prestige of the institute and its director. Together they played a pivotal role in the establishment of genetics in Germany. Without them the discipline would have developed much more slowly and along a divergent path. (shrink)

Multimedia learning research addresses the question of how to design instructional material effectively. Signaling and adding graphics are typical instructional means that might support constructing a mental model, particularly when learning abstract content from multiple representations. Although signals can help to select relevant aspects of the learning content, additional graphics could help to visualize mentally the subject matter. Learners’ prior knowledge is an important factor for the effectiveness of both types of support: signals and added graphics. Therefore, we conducted an (...) experimental study situated in a university course of computer science with N = 124 participants. In our 2 × 2 factorial design, we investigated the effects of signals and illustrating graphics on learning outcomes and their potential interplay. Based on our regression analysis, we revealed prior knowledge as a significant moderator. Although learners with low levels of prior knowledge can profit from all types of help but still gain rather weak learning outcomes, learners with medium levels of prior knowledge profit from the synergy of both helps. With higher levels of prior knowledge, signals were particularly hampering. To improve the understanding of these supportive or hampering effects, a more fine-grained analysis of these processes and motivational effects is necessary. (shrink)

Calculation of the mean of an observable in quantum mechanics is typically assumed to require that the state vector be in the domain of the corresponding self-adjoint operator or for a mixed state that the operator times the density matrix be in the trace class. We remind the reader that these assumptions are unnecessary. We state what is actually needed to calculate the mean of an observable as well as its variance.