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Alternative forms of assessment in mathematical modelling:The AlPMo projekt in practice and research
No full textDas Projekt AlPMo (Alternative Prüfungsformen beim mathematischen Modellieren) untersucht den Einsatz digitaler Portfolios als alternative Prüfungsform im Mathematikunterricht. Die Publikation stellt sowohl die schulpraktische Umsetzung einer Unterrichtseinheit mit Modellierungsaufgaben als auch die hochschuldidaktische Integration in ein Seminar für Lehramtsstudierende vor. Ziel ist es, Modellierungskompetenzen ganzheitlich zu erfassen und innovative Wege der Leistungsbewertung zu erproben. Ergänzend werden begleitende wissenschaftliche Studien beschrieben, die die Wirksamkeit
des Seminarkonzepts, die Perspektiven von Lehrkräften und Lernenden sowie Einflussfaktoren auf die Portfolio-Note analysieren.The AlPMo Project (in German: Alternative Prüfungsformen beim mathematischen Modellieren) investigates the use of digital portfolios as an alternative form of assessment in mathematics modelling education. The publication presents both the practical implementation of a teaching unit with modelling tasks in schools and the integration of the concept into a university seminar for pre-service teachers. The aim is to comprehensively assess modelling competencies and to explore innovative methods of performance evaluation. In addition, accompanying scientific studies are described that analyze the effectiveness of the seminar concept, the perspectives of teachers and learners, and factors influencing the portfolio grade
Alternative Transaxillary Access for Transcatheter Aortic Valve Implantation
No full textBackground/Objectives: Currently, the transfemoral approach is recognized as the primary method for accessing transcatheter aortic valve implantation (TAVI). However, alternative techniques are needed when the transfemoral access is not suitable. We proposed that a modified transaxillary approach through the distal left axillary artery is both viable and safe for conducting TAVI, potentially offering benefits for patients. Methods: From December 2018 to February 2024, a total of 24 patients (7 women, average age 77.9 ± 8 years) received TAVI using transaxillary access via the left axillary artery. The participants suffered from symptomatic severe aortic stenosis and were deemed TAVI candidates with iliofemoral anatomy unsuitable for a transfemoral route. The patient group displayed a high perioperative risk profile, with significant peripheral artery disease or severe obstructive infrarenal aortic conditions. The implantation of the aortic prosthesis was carried out through the left distal axillary artery. A balloon-expandable valve was used in every instance. Results: In the examined cohort, the 30-day mortality rate was 4.2%. A new pacemaker was necessary for four patients (16.7%). One case exhibited a new moderate neurological dysfunction. Additionally, one patient required surgical revision of the access point due to ischemia. Conclusions: Our findings indicate that transaxillary TAVI via the distal left axillary artery has yielded encouraging outcomes. This approach is practicable and safe, does not prolong the procedure, minimizes surgical trauma, ensures excellent access regardless of chest anatomy, and is sparing for the brachial plexus. As a single-center pilot study, our findings require confirmation in larger, prospective cohorts with extended follow-up to fully validate the safety and long-term efficacy of this technique
A matter of life and death. The Akkadian verb dâku and Tukultī-apil-Ešarra IV*'s war with Mukīn-zēri (731–727 BC)
No full textDiese Anmerkung untersucht die genauen Konnotationen des akkadischen Verbs daku "toten" und zeigt, dass seine gelegentliche Obersetzung mit dem nicht todlichen "besiegen" nach den derzeitigen Erkenntnissen ungerechtfertigt ist. Dies hat entscheidende Konsequenzen fur die assyrische Invasion Babyloniens ab 731 v. Chr. und erfordert eine neue Chronologie der Ereignisse der Invasion. Daraus lasst sich ableiten, dass sich die Regierungszeit des vorherigen babylonischen Konigs Mukin-zeri tatsachlich mit der van Tukulti-apil-Esarra IV*. uberschneidet (wie im Ptolemaischen Kanan angedeutet) und dass Mukin-zeri erst 727 v. Chr. bei einer Belagerung starb, nur wenige Monate vor
Tukulti-apil-Esarra IV*. selbst. Dies deutet darauf hin, dass die assyrische Besetzung Babyloniens van Anfang an chaotisch verlief und nicht erst, nachdem Marduk-apla-iddina (11.) 722 v. Chr. den Thran bestiegen hatte.This note investigates the precise connotations of the Akkadian verb daku 'to kill', demonstrating that its occasional translation as the non-lethal 'to defeat' is unwarranted according to present evidence. This has crucial consequences for the Assyrian invasion of Babylonia from 731 BC onwards, demanding a new chronology for the invasion's events. As a result, it can be shown that the preceeding Babylonian king Mukin-zeri's reign actually overlapped with that of Tukulti-apil-Esarra IV* (as implied by the Ptolemaic Canon), and that Mukin-zeri only died in 727 BC in a siege, a scarce few months before Tukulti-apil-Esarra IV* himself. This suggests that the Assyrian occupation of Babylonia was chaotic from the very outset, rather than only after Marduk-apla-iddina (11) took the throne in 722 BC
Angular stable plate fixation provides favorable biomechanical stability in simulated T-shaped acetabular fractures: a biomechanical study
No full textBackground and purpose: The treatment of acetabular fractures remains technically demanding. In the case of reduced bone quality or fracture morphology reducing the amount of bone available for fixation, locking plates should provide considerable advantages. The aim of the present study was to compare conventional and locking plate fixation. It was hypothesized that locking plate fixation provides less displacement and higher construct stiffness. Methods: A T-shaped acetabular fracture was simulated in 16 synthetic pelvic models. The fracture was addressed with a biplanar 10-hole 2-column plate buttressing the medial acetabular wall. Optical markers were attached to the fracture sites for motion tracking. Standardization of the acetabulum loading mechanism was performed using a unipolar hemiarthroplasty. The primary outcome measure was displacement at the fracture sites. The secondary outcome measure was the construct stiffness (N/mm). Results: Fracture displacement was less in the group of angular stable implants compared with the group fixed with conventional non-locking implants. Under cyclic loading displacement was less in the group of locking plate fixation. No differences in mean initial axial stiffness were detected between locking plate fixation (407 N/mm) and conventional plating (308 N/mm, ∆ 99 N/mm, 95% confidence interval –48 to 245). Conclusion: We showed that locking plate fixation buttressing the medial acetabular wall achieved less fracture displacement but showed no differences in axial stiffness compared with conventional plating
Combination of differently structured pump beams for selective mode excitation
No full textDigital micromirror devices (DMD) enable the flexible and selective excitation of transverse resonator modes through spatial gain shaping. With the aim to increase the output power limited by the DMD damage threshold, a pump beam combining approach was investigated. One pump beam was shaped by a DMD, such that a gain distribution adapted to a target mode was realized, whereas a second pump beam provided additional but mode-unspecific gain for a wide range of transverse modes. Although the second pump beam allowed to reduce the power incident on the DMD by a factor of three to five, output power scaling could also be achieved by adapting the mode-like pattern displayed on the DMD instead. Still, modal analysis of the observed multi-mode lasing revealed characteristic properties of pump distributions adapted to Hermite-Gaussian HGm,0 modes: a center-heavy pump distribution at first distinctly excites the target mode and eventually low-order modes, whereas an eccentric pump distribution reduces the lasing threshold at the expense of distinction to the neighboring modes
Cup and cap products for cohomology and homology groups of ample groupoids
No full textThis paper explores the cup and cap products within the cohomology and homology groups of ample groupoids, focusing on their applications and fundamental properties. Ample groupoids, which are étale groupoids with a totally disconnected unit space, play a crucial role in the study of topological dynamical systems and operator algebras. We introduce the cup product, which defines a bilinear map on cohomology classes, providing a graded ring structure, and the cap product, which defines a bilinear map relating homology and cohomology. The paper aims to make these concepts accessible to a broader mathematical audience, offering clear definitions and detailed explanations. We also demonstrate an application of the cap product in the analysis of automorphisms of groupoid C*-algebras. Specifically, we show how it helps determine the asymptotic innerness of automorphisms.
Our results include the first explicit computations of cup products in the cohomology of tiling spaces, which may pave the way for new research in this area
CutFEM forward modeling for EEG source analysis
No full textIntroduction: Source analysis of Electroencephalography (EEG) data requires the computation of the scalp potential induced by current sources in the brain. This so-called EEG forward problem is based on an accurate estimation of the volume conduction effects in the human head, represented by a partial differential equation which can be solved using the finite element method (FEM). FEM offers flexibility when modeling anisotropic tissue conductivities but requires a volumetric discretization, a mesh, of the head domain. Structured hexahedral meshes are easy to create in an automatic fashion, while tetrahedral meshes are better suited to model curved geometries. Tetrahedral meshes, thus, offer better accuracy but are more difficult to create. Methods: We introduce CutFEM for EEG forward simulations to integrate the strengths of hexahedra and tetrahedra. It belongs to the family of unfitted finite element methods, decoupling mesh and geometry representation. Following a description of the method, we will employ CutFEM in both controlled spherical scenarios and the reconstruction of somatosensory-evoked potentials. Results: CutFEM outperforms competing FEM approaches with regard to numerical accuracy, memory consumption, and computational speed while being able to mesh arbitrarily touching compartments. Discussion: CutFEM balances numerical accuracy, computational efficiency, and a smooth approximation of complex geometries that has previously not been available in FEM-based EEG forward modeling
Das Ende des Dornröschenschlafs?:Repräsentationen der Kleinstadt Billerbeck im 20. Jahrhundert
No full textDie vorliegende Dissertation verknüpft das Forschungsfeld zum Kleinstadtwesen mit dem zur Stadt als Wahrnehmungs- und Aneignungsraum. Anhand der münsterländischen Kleinstadt Billerbeck werden im Zeitraum von etwa 1920 bis 1980 die Konstruktionen städtischer Selbstbilder untersucht. So wird gezielt nach Auswirkungen allgemeiner Prozesse auf Selbstbildkonstruktionen, nach Inhalten und Funktionen städtischer Selbstbilder gefragt sowie nach der Rolle von Akteuren. Wie haben Einwohner oder bestimmte Gruppen ihre Stadt wahrgenommen?
Diesen Fragen wird auf drei Ebenen nachgegangen: Auf der physischen Ebene mittels Analyse der Auswirkungen massiver Veränderungen des Stadtbildes auf die entstandenen Selbstbilder (Beispiel: Stadtkernsanierung); auf der mentalen Ebene mittels Analyse von Texten, Bildern und lokaler Kommunikation (Beispiel: Werbebroschüren) sowie auf der erlebten Ebene mittels Analyse der Repräsentationen bei öffentlichen Festen (Beispiel: Stadtjubiläum)
demokratie macht raum:Zivilgesellschaftliche Beteiligung an der Transformation der Braunkohlereviere Rheinland und Lausitz
No full textDer deutsche Braunkohleausstieg erfolgt in einer Zeit, die von multiplen, miteinander verwobenen Krisen geprägt ist. Insbesondere die Herausforderungen der Klimakrise erfordern tiefgreifende gesellschaftliche Veränderungen und entsprechende Aushandlungen. Ein beträchtlicher Teil der Bevölkerung hat jedoch das Vertrauen in das politische System verloren. Vor dem Hintergrund der Repräsentations- und Klimakrise stellt Maren Krätzschmar zivilgesellschaftliche Beteiligung in den Mittelpunkt ihrer Arbeit. "demokratie macht raum" zeigt Möglichkeiten, aber auch Grenzen, zivilgesellschaftlicher Beteiligung in der Transformation der Braunkohlereviere Rheinland und Lausitz auf. Die Autorin ordnet bestehende Beteiligungsangebote demokratietheoretisch ein. Auf dieser Grundlage untersucht sie mit Bezug auf Macht- und Raumformen, warum zivilgesellschaftliche Beteiligung trotz des gesellschaftlichen Diskurses um partizipative Erweiterungen der repräsentativen Demokratie weiterhin eine stark untergeordnete Rolle spielt. Mit Bezug auf die demokratische Repräsentationskrise macht sie abschließend deutlich, wie nicht partizipativ angelegte Transformationsprozesse potenziell zu gesellschaftlicher Frustration beitragen und die Demokratie gefährden.The German lignite phase-out is taking place at a time characterized by multiple, interwoven crises. Particularly, the climate crisis challenges require far-reaching social changes and corresponding negotiations. However, a considerable proportion of the population has lost confidence in the political system. Against the backdrop of the crisis of representation and the climate crisis, Maren Krätzschmar places civil society participation at the center of her work. "demokratie macht raum" shows the possibilities, but also the limits, of civil society participation in the transformation of the Rhineland and Lusatia lignite mining regions. The author classifies existing opportunities for participation in terms of democratic theory. She then examines, with reference to forms of power and space, why civil society participation continues to play a very subordinate role despite the societal discourse on participatory extensions of representative democracy. Regarding the crisis of representation, she highlights that non-participatory transformation processes potentially contribute to societal frustration and endanger democracy
Early ERPs dissociate subjectively nonconscious low- and high-level face processing
No full textThere is an ongoing debate about the extent to which faces are processed if they are not consciously perceived. In the present study, we used event-related potentials (ERPs) to investigate neural responses to faces and two types of control stimuli (monochrome color-matched ovals and Fourier phase-scrambled faces), which allowed us to dissociate low-level and high-level face processing. Based on a pre-registered sequential Bayesian sampling protocol, we recorded the electroencephalogram (EEG) from 40 participants and compared the average amplitude of early components of the ERP (P1, N170) between faces, scrambles, and blanks presented for 17 ms, while the mask followed directly or 200 ms after the target stimulus. Participants were asked to rate their subjective perception after each trial on a perceptual awareness scale, and only trials with the lowest rating in the masked condition were considered as subjectively nonconscious. Matching the pre-registered hypotheses, P1 amplitudes were higher for faces and scrambles compared to blanks but did not differ between faces and scrambles. This pattern was found for conscious and nonconscious faces, however, with smaller yet reliable differences in the latter case. In contrast, the N170 reliably differentiated between faces and both types of control stimuli (scrambles and blanks), again for conscious and, with attenuated differences, also for nonconscious faces. Findings support the hypothesis of two early stages of face processing, which are at least partially independent of consciousness awareness of stimuli. The P1 stage is associated with low-level processing, while the N170 reflects processing of face-related configural information