Abstract. We given an upper bound for the least dilatation arising from a pseudo-Anosov map of a closed surface of genus greater or equal to three.

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Zusammenfassung Schulpraktische Studien sollen als zentrale Lerngelegenheiten im Lehramtsstudium den Studierenden die Möglichkeit bieten, Praxiserfahrungen zu sammeln, Theorie mit Praxis zu verzahnen und ihre Berufswahlmotivation kritisch zu reflektieren. Bisherige Studien beschäftigten sich meist mit der Einschätzung subjektiver Kompetenzentwicklung und es gibt nur wenige Belege dafür, ob die Studierenden ihre Berufswahlmotivation im Verlauf der Praktika reflektieren und verändern. Diese Studie untersucht, wie stabil die motivationalen Orientierungen im Laufe des Integrierten Semesterpraktikums sind und welche Faktoren neben der reinen Praxiserfahrung eine Rolle für die möglichen Veränderungen spielen. Hierfür wurden 201 Studierende sowohl vor als auch nach ihrem Praktikum befragt. Die Ergebnisse der Strukturgleichungsmodellierungen zeigen, dass die Berufswahlmotive äußerst stabil sind und sich nur die Lehrerselbstwirksamkeit im Verlauf des Praktikums verändert. Die Untersuchung interindividueller Entwicklungsverläufe hat gezeigt, dass lediglich die Reflexionsgelegenheiten neben der reinen Praxiserfahrung einen kleinen positiven Effekt auf die Entwicklung der Lehrerselbstwirksamkeit aufweisen. K 368 M. Bauer et al. Schlüsselwörter Schulpraktische Studien · Berufswahlmotivation · Lehrerselbstwirksamkeit · Lehrerbildung · Längsschnittstudie · Strukturgleichungsmodellierung Analysis of the stability and variability of motivational beliefs of teacher candidates during their long-term internshipAbstract Pedagogical field experiences in teacher training programs provide important learning opportunities for pre-service teachers to obtain practical experiences in a working environment, which are supposed to enable them to link the theoretical skills to their practical ones, to develop professional competencies and to reflect on their own career-choice. While many studies focus on students' self-perception of competence, few studies have addressed the change of motivational beliefs and the students' reflection on their motivation for becoming teachers. This study investigates the stability and variability of the motivational beliefs of future teachers during their long-term internship and aims to identify the predictors of the development of these beliefs. In this study, 201 students were surveyed before and after their longterm internship. The findings from the structural equation modelling analyses reveal a high stability of motivational beliefs and suggest that (a) only students' selfefficacy increases during the pedagogical field experiences and (b) only the opportunities to reflect during the accompanying courses at the university have a small effect on the development of teacher self-efficacy.

Precise genome engineering is essential for both basic and applied research, permitting the manipulation of genes and gene products in predictable ways. The irruption of the CRISPR/Cas technology accelerated the speed and ease by which defined exogenous sequences are integrated into specific loci. To this day, a number of strategies permit gene manipulation. Nevertheless, knock-in generation in multicellular animals remains challenging, partially due to the complexity of insertion screening. Even when achieved, the analysis of protein localization can still be unfeasible in highly packed tissues, where spatial and temporal control of gene labeling would be ideal. Here, we propose an efficient method based on homology-directed repair (HDR) and single-strand annealing (SSA) repair pathways. In this method, HDR mediates the integration of a switchable cassette. Upon a subsequent CRISPR-triggered repair event, resolved by SSA, the cassette is seamlessly removed. By engineering the Hedgehog (Hh) pathway components, we demonstrated fast and robust knock-in generation with both fluorescent proteins and short protein tags in tandem. The use of homology arms as short as 30 base pairs further simplified and cheapened the process. In addition, SSA can be triggered in somatic cells, permitting conditional gene labeling in different tissues. Finally, to achieve conditional labeling and manipulation of proteins tagged with short protein tags, we have further developed a toolbox based on rational engineering and functionalization of the ALFA nanobody.

Combinatorial signaling is key to instruct context-dependent cell behaviors. During embryonic development, adult homeostasis and disease, Bone Morphogenetic Proteins (BMPs) act as dimers to instruct specific cellular responses. BMP ligands can form both homo- or heterodimers; however, obtaining direct evidence of the endogenous localization and function of each form has proven challenging. Here, we make use of precise genome editing and direct protein manipulation via protein binders to dissect the existence and functional relevance of BMP homo- and heterodimers in the Drosophila wing imaginal disc. This approach revealed in situ the existence of Dpp (BMP2/4)/Gbb (BMP5/6/7/8) heterodimers. We found that Gbb, despite being produced by all the cells of the wing imaginal disc, is only secreted by the cells in which Dpp is expressed. Dpp and Gbb form a gradient of heterodimers whereas neither Dpp nor Gbb homodimers are evident under endogenous physiological conditions. We find that the formation of heterodimers is critical for obtaining optimal signaling and long-range BMP distribution in the developing wing. These results indicate that Dpp/Gbb heterodimers are the active signal required for epithelial patterning and growth.

Perceptions of synthetic surfaces used in football can vary considerably between players, and obtaining reliable feedback is challenging. The aim of this study was to develop a suitable process and evaluate the merits of establishing a sensory panel to assess the subjective attributes of third generation synthetic turf surfaces (3G turf) used in football. Focus groups with 12 male and 13 female footballers were conducted on an outdoor 3G turf pitch to develop a common language to describe sensory feedback related to player–surface interactions. Post-session analysis revealed two main themes related to player–surface interactions: hardness and grip. These themes were broken down further into five sensory attributes (Movement Speed, Slip, Movement Confidence, Leg Shock and Give) which were investigated further in an indoor test area containing ten 3G turf surfaces with controlled surface properties. A panel consisting of 18 University footballers (11 male and 7 female) undertook a screening and training session to refine the language associated with the sensory attributes and become familiar with the testing protocol. During a final evaluation session, players were asked to discriminate between surfaces using the paired comparison method for each of the sensory attributes. Player consistency remained similar between the screening and evaluation sessions whilst the panel’s ability to discriminate between surfaces improved during the evaluation session. Sensory training can therefore be a useful approach to aid players in differentiating between surfaces and lead to a greater understanding of athlete perceptions of surface attributes.

The Notch signaling pathway is highly conserved in all animal metazoa: upon Notch receptor activation, transcription of Notch target genes is turned on by an activator complex that centers on the transcription factor CSL. In the absence of signal, CSL assembles transcriptional repression complexes that display remarkable evolutionary diversity. The major antagonist of Notch signaling in insects named Hairless was originally identified in Drosophila melanogaster. It binds to the Drosophila CSL homologue Suppressor of Hairless [Su(H)] and recruits the two general co-repressors, Groucho and C-terminal binding protein. Whereas the majority of Notch signaling components is conserved between insects and vertebrates, Hairless is found only in insects. Here, we present the analysis of the Hairless gene from Daphnia pulex and, hence, for the first time from a crustacean. Daphnia and Drosophila Hairless protein sequences are highly diverged. Known functional domains, however, the Su(H), Groucho and the C-terminal binding protein interactions domains, are well conserved. Moreover, direct binding of the Daphnia Hairless protein and the respective Drosophila interaction partners was detected, demonstrating the conservation at the molecular level. In addition, interaction between Daphnia Hairless and Drosophila Su(H) was demonstrated in vivo, as co-overexpression of the respective genes during Drosophila development resulted in the expected downregulation of Notch activity in the fly. Structural models show that the Hairless-Su(H) repressor complexes from Daphnia and Drosophila are almost indistinguishable from one another. Amino acid residues in direct contact within the Hairless-Su(H) complex are at absolutely identical positions in the two homologues.

Background Sports-related concussions are the most common cause of head injury in adolescents and young adults. Typical treatment methods for this injury include cognitive and physical rest. Evidence suggests that physical activity and physical therapy interventions can be beneficial to decrease post-concussion symptoms. Purpose The aim of this systematic review was to investigate the effectiveness of physical therapy interventions for adolescent and young adult athletes post-concussion. Study Design Systematic Review Methods The following databases were utilized for the search: PubMed, CINAHL, Proquest, MEDLINE, SPORTDiscus, and SCOPUS. The search strategy focused on athletes, concussions, and physical therapy interventions. Data extraction from each article included: Authors, subjects, gender, mean age, age range, specific sport, acute or chronic concussion, first or recurrent concussion, treatments for intervention and control group, and outcomes measured. Results Eight studies met the inclusion criteria. Six of the eight articles scored seven or higher on the PEDro Scale. Physical therapy intervention(s), such as an aerobic intervention or a multimodal approach, show improvements in time to recovery and reduction of post-concussion symptoms in patients who have had a concussion. Physical activity and physical therapy as early as a couple days following injury, is beneficial at decreasing post-concussion symptoms, allows for earlier return to play, and/or shorter days to recovery, and is considered safe for treating post-concussion symptoms. Conclusion This systematic review demonstrates that physical therapy interventions including aerobic exercise and multimodal approaches have been found to be beneficial in treating adolescent and young adult athletes post-concussion. Utilizing aerobic or multimodal interventions for this population allows for a quicker symptom recovery and return to sport than traditional treatment of physical and cognitive rest. Future research should investigate the superior intervention for adolescents and young adults with post-concussion syndrome and determine if a single treatment or a multimodal approach is more beneficial.