The Challenges, Reforms, and Future Prospects of Elementary and Lower Secondary Mathematics Education in Germany

Keeping its original form of an interview, this article presents a discussion about the challenges, reforms, and the prospects of mathematics education in Germany. The interview addresses aims and goals, contents and processes of mathematics teaching. Compared with the guiding ideas some years ago, more emphasis is put on modeling today. The idea that every student should have enough mathematics knowledge and the disappointing results of Germany in the PISA-2000 comparison may have caused this change. Moreover, Germany faces, like other countries do, some basic problems in mathematics teaching, addressed here as the balance problem, the coherence problem, the curriculum problem, the classroom organization problem, the computer problem, and the teacher education and development problem. The interview also tries to show how these problems are going to be tackled in Germany. For the prospects, being able to apply mathematics in the real world, being able to understand the mathematical concepts and rules, and having the potential of cultivating the own thinking are the main concerns of mathematical literacy in Germany

Microstructure-based modeling of elastic functionally graded materials: One dimensional case

Functionally graded materials (FGMs) are two-phase composites with continuously changing microstructure adapted to performance requirements. Traditionally, the overall behavior of FGMs has been determined using local averaging techniques or a given smooth variation of material properties. Although these models are computationally efficient, their validity and accuracy remain questionable, since a link with the underlying microstructure (including its randomness) is not clear. In this paper, we propose a modeling strategy for the linear elastic analysis of FGMs systematically based on a realistic microstructural model. The overall response of FGMs is addressed in the framework of stochastic Hashin-Shtrikman variational principles. To allow for the analysis of finite bodies, recently introduced discretization schemes based on the Finite Element Method and the Boundary Element Method are employed to obtain statistics of local fields. Representative numerical examples are presented to compare the performance and accuracy of both schemes. To gain insight into similarities and differences between these methods and to minimize technicalities, the analysis is performed in the one-dimensional setting.Comment: 33 pages, 14 figure

Microscopy-based siRNA screen of microglia to identify neuroprotective drug targets

The uploaded accepted version corresponds to pages E419-E429 of the publication "GLIA Edinburgh 2017: Abstracts Oral Presentations, Posters, Indexes" available at https://onlinelibrary.wiley.com/doi/10.1002/glia.23157.Neuroinflammation is a fundamental process contributing to the death of neurons in neurodegenerative diseases, such as Parkinson ́s (PD) or Alzheimer ́s disease (AD). During this process, activated microglia secrete cytotoxic substances which lead to neuronal death (1). Therefore, we are looking for the molecular mechanism that reverses the inflammatory activation of microglia, since this knowledge would be essential to protect from neurodegeneration. Our previous data (2) indicate that adipose derived mesenchymal stem cells (ASCs) exert important anti-inflammatory actions on microglia. We observed that microglia exposed to ASCs or their secreted factors (conditioned medium, CM) underwent a dramatic cell shape change into a highly elongated morphology (Fig. 1A), similar to the phenotype of microglia observed in a healthy brain (3). The elongation induced by ASCs was associated with a decrease of the pro-inflammatory cytokine TNFalpha (Fig. 1B) as well as with an upregulation of neurotrophic factors (2). Thus, ASC stimulated microglia represent an ideal tool to study the intracellular events necessary for the transition from inflammatory activated to non-inflammatory neuroprotective microglia. Exploiting these anti-inflammatory properties of ASCs we set up a microscopy-based siRNA screen (Fig. 1C), identifying its hits by cell morphology (see Fig. 1A). In this light, we searched for molecules that inhibited the anti-inflammatory ASC-induced phenotype and thus are involved in the transition from neurotoxic microglia to neuroprotective ones. As changes in the cell shape are intrinsically related to changes of the cytoskeleton, we carried out the screen with the major cytoskeletal regulators. In addition, we included regulators of microglia-specific activation/inflammatory pathways as siRNA targets. Our project is the first siRNA screen performed in primary microglia and we have identified a list of molecules that are specifically implicated in the reversion from activated to neuroprotective microglia. Since our positive hits represent potential neuroprotective drug targets, the outcome of this screen opens up a variety of novel investigation lines and therapies in PD, AD or other neurodegenerative diseases.Michael J Fox Foundation research gran

Meeting report: Seventh Annaberg EMBO Workshop 'Membrane traffic in the secretory pathway', Goldegg, Austria, 9-14 January 2007

The seventh Annaberg Conference entitled ‘Membrane Traffic in the Secretory Pathway’ was, like previous meetings, very successful. The scenic Austrian village of Goldegg and its castle gave the meeting a great atmosphere, although this time we missed the wintry landscape. Nevertheless, many outstanding speakers presented the latest research in membrane dynamics along the secretory and endocytic pathways, and the poster sessions in the evenings were no less exciting. Within the topic of membrane trafficking, the talks and posters ranged from lipids to autophagy to signaling, and from mitosis to mitochondria, which made this conference very diverse and dynamic. The high quality of the talks ensured that all these different topics were effectively conveyed and provoked lively discussions. We would like to apologize that we can only report on a selection of the presented talks because of limited space, and therefore will not mention all the invited speakers in this report