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Slippix – der Schleifstab
No full textLehrkräfte sind mit Blick auf ihre heterogenen Lerngruppen im Technikunterricht darauf angewiesen, einen differenzierten Unterricht zu gestalten, der personelle, organisatorische und sachliche Ressourcen miteinbezieht. Bei Fertigungsaufgaben bietet sich daher der Einsatz von Vorrichtungen an, über die auf die unterschiedlichen Lernvoraussetzungen von Schüler:innen reagiert werden kann. So lassen sich die Anforderungen von Fertigungsaufgaben gezielt variieren.
Die vorliegende Publikation beschreibt den Schleifstab „Slippix“, der für jegliche Schleifarbeiten an Ecken, Kanten und Flächen verwendet werden kann, bei denen das Werkstück fest eingespannt ist. Ähnlich wie beim Arbeiten mit einer Holzfeile, wird bei „Slippix“ die gesamte Länge des Stabs genutzt und über das Holz geführt. Slippix ermöglicht jedoch die Anpassung der Körnungen. „Slippix“ ist in drei Versionen herstellbar. Neben der Standardversion (ohne Handgriffe), gibt es noch Versionen mit Handgriffen und mit einem Haltesteg. Die einzelnen Versionen unterscheiden sich zum Teil in ihren Maßen.
Die Dokumentationen umfasst neben den Fertigungsunterlagen kleinschrittige Bauanleitungen, die ggf. auch gemeinsam mit Schüler:innen umgesetzt werden können. Zudem enthalten sind beispielhafte Kostenrechnungen sowie Schablonen, die zur Erleichterung des Fertigungsprozesses verwendet werden können. Des Weiteren wird durch vereinzelt beigefügte interaktive technische Zeichnungen die Adaption der Vorrichtungen ermöglicht
Frag nach! Intervention des Monitorings des Sprachverstehens bei Kindern mit Sprachverständnisstörungen
No full textMonitoring des Sprachverstehens (MSV) bezieht sich auf das Erkennen von Nicht-/Missverstehen und notwendige Klärungsstrategien wie spezifisches Nachfragen. Diese kommunikativ bedeutsame Strategie ist bei Kindern mit Sprachentwicklungsstörungen bzw. Sprachverständnisstörungen oftmals nicht oder nur eingeschränkt entwickelt. Kleine Fallstudien belegen hier jedoch wirksame Interventionen. Eine Intervention (Schönauer-Schneider, 2019) beinhaltet fünf Bausteine zur Förderung, die im Artikel vorgestellt werden
The Mediator kinase module enhances polymerase activity to regulate transcriptional memory after heat stress in Arabidopsis
No full textPlants are often exposed to recurring adverse environmental conditions in the wild. Acclimation to high temperatures entails transcriptional responses, which prime plants to better withstand subsequent stress events. Heat stress (HS)-induced transcriptional memory results in more efficient re-induction of transcription upon recurrence of heat stress. Here, we identified CDK8 and MED12, two subunits of the kinase module of the transcription co-regulator complex, Mediator, as promoters of heat stress memory and associated histone modifications in Arabidopsis. CDK8 is recruited to heat-stress memory genes by HEAT SHOCK TRANSCRIPTION FACTOR A2 (HSFA2). Like HSFA2, CDK8 is largely dispensable for the initial gene induction upon HS, and its function in transcriptional memory is thus independent of primary gene activation. In addition to the promoter and transcriptional start region of target genes, CDK8 also binds their 3ʹ-region, where it may promote elongation, termination, or rapid re-initiation of RNA polymerase II (Pol II) complexes during transcriptional memory bursts. Our work presents a complex role for the Mediator kinase module during transcriptional memory in multicellular eukaryotes, through interactions with transcription factors, chromatin modifications, and promotion of Pol II efficiency
Nanopore adaptive sampling effectively enriches bacterial plasmids
No full textBacterial plasmids play a major role in the spread of antibiotic resistance genes. However, their characterization via DNA sequencing suffers from the low abundance of plasmid DNA in those samples. Although sample preparation methods can enrich the proportion of plasmid DNA before sequencing, these methods are expensive and laborious, and they might introduce a bias by enriching only for specific plasmid DNA sequences. Nanopore adaptive sampling could overcome these issues by rejecting uninteresting DNA molecules during the sequencing process. In this study, we assess the application of adaptive sampling for the enrichment of low-abundant plasmids in known bacterial isolates using two different adaptive sampling tools. We show that a significant enrichment can be achieved even on expired flow cells. By applying adaptive sampling, we also improve the quality of de novo plasmid assemblies and reduce the sequencing time. However, our experiments also highlight issues with adaptive sampling if target and non-target sequences span similar regions.
IMPORTANCE
Antimicrobial resistance causes millions of deaths every year. Mobile genetic elements like bacterial plasmids are key drivers for the dissemination of antimicrobial resistance genes. This makes the characterization of plasmids via DNA sequencing an important tool for clinical microbiologists. Since plasmids are often underrepresented in bacterial samples, plasmid sequencing can be challenging and laborious. To accelerate the sequencing process, we evaluate nanopore adaptive sampling as an in silico method for the enrichment of low-abundant plasmids. Our results show the potential of this cost-efficient method for future plasmid research but also indicate issues that arise from using reference sequences
Benefits of combined fluorescence lifetime imaging microscopy and fluorescence correlation spectroscopy for biomedical studies demonstrated by using a liposome model system
No full textDrug delivery systems play a pivotal role in targeted pharmaceutical transport and controlled release at specific sites. Liposomes, commonly used as drug carriers, constitute a fundamental part of these systems. Moreover, the drug–liposome model serves as a robust platform for investigating interaction processes at both cellular and molecular levels. To advance our understanding of drug carrier uptake mechanisms, we employed fluorescence lifetime imaging microscopy (FLIM) and fluorescence correlation spectroscopy (FCS), leveraging the unique benefits of two-photon (2P) excitation. Our approach utilized giant unilamellar vesicles (GUVs) as a simplified model system for cell membranes, labelled with the amphiphilic fluorescent dye 3,3′-dioctadecyloxa-carbocyanine (DiOC18(3)). Additionally, large unilamellar vesicles (LUVs) functioned as a drug carrier system, incorporating the spectrally distinct fluorescent sulforhodamine 101 (SRh101) as a surrogate drug. The investigation emphasized the diverse interactions between GUVs and LUVs based on the charged lipids employed. We examined the exchange kinetics and structural alterations of liposome carriers during the uptake process. Our study underscores the significance of employing 2P excitation in conjunction with FLIM and FCS. This powerful combination offers a valuable methodological approach for studying liposome interactions, positioning them as an exceptionally versatile model system with a distinct technical advantage
On the overlapping discourse functions of Spanish ‘cómo que’ and French ‘comment ça’ interrogatives
No full textWe present evidence for an overlap in the discourse functions of Spanish cómo que XP ‘how that complementizer’ and French comment ça ∅/XP ‘how that demonstrative’ interrogatives. We argue for three shared discourse functions: clarification requests, mirative questions, and expressions of disagreement. We show that these functions are cued by an interplay of morpho-syntactic and contextual factors. At the morpho-syntactic level, whether grammatical person shifts (is indirectly cited) compared to the previous turn and whether additional linguistic material (the ‘remnant’) is present after ‘how that’ were found to be important predictors of discourse function. At the contextual level, whether and how the speaker continues her turn after the interrogative is our most significant predictor. We quantify the degree to which these and other cues allow for a prediction of the discourse functions and find that the resulting model predicts more clarification request uses and fewer mirative and disagreement uses than empirically attested. This indicates that some cues for these two readings are missing from our model. We propose that prosody might be one of them
The German validation of the Body Perception Questionnaire-Short Form (BPQ-SF) and its relation to current self-report measures of interoception
No full textThe Body Perception Questionnaire-Short Form (BPQ-SF) is one of the most used questionnaires to assess interoception. Although the BPQ-SF has been translated into different languages, there is no validated German questionnaire adaptation so far. Furthermore, empirical evidence outlining how the BPQ-SF relates to novel theories of interoception that distinguish between different facets, such as attention and accuracy, is still missing. The current study therefore aims at (1) validating the German version of BPQ-SF (with data from three different sites, Ntotal = 1292) and (2) relating it to the constructs of interoceptive accuracy and attention. In line with the original validation of the BPQ-SF, in the German version, an adequate three-factor structure and good internal consistency were found. However, reliability indexes varied between good, for the supra-and subdiaphragmatic scales and poor, for the body awareness scale. The three scales of the BPQ-SF showed significant associations with interoceptive measures and, more importantly, were related to both interoceptive accuracy and attention, suggesting that they mirror a mixture of both constructs. Finally, in relation to measures of psychopathology, the supra-and subdiaphragmatic (but not the body awareness) scales were positively related to alexythimic, anxious, and depressive tendencies. These findings provide evidence for the usability of the German version of the BPQ-SF and further shed light on the heterogeneity of the existing self-report measures of interoception
Association between time of assessment within a school year and physical fitness of primary school children
No full textThe dissociation of effects of age, time of assessment and cohort is a well-known challenge in developmental science. We examined effects of time of assessment in the school year on children’s physical fitness using data from 75,362 German third-graders from seven cohorts. Children were tested once either in the first or second school term of third grade. Tests examined cardiorespiratory endurance (6-min run), coordination (star-run), speed (20-m sprint), lower (standing long jump) and upper (ball-push test) limbs muscle power, and flexibility (stand-and-reach test). We estimated the effect of time of assessment using a regression discontinuity design specified in a linear mixed model with random factors child and school and adjusted for age, sex, and cohort effects. Coordination, speed, and upper limbs muscle power were better in second compared to first school term, with boys exhibiting a larger increase of upper limbs muscle power than girls. There was no evidence for changes in cardiorespiratory endurance, lower limbs muscle power, and flexibility between assessments. Previously reported age and sex effects as well as secular fitness trends were replicated. There is thus evidence for improvement of some physical fitness components beyond age and cohort effects that presumably reflects the benefit of physical activity in physical education and other settings. Effects of assessment time should be taken into consideration in performance-based grading or norm-based selection of children
Deals mit Diktaturen
No full textDer Umgang mit Diktatoren hat die bundesdeutsche Demokratie von Anfang an herausgefordert. Frank Bösch zeigt auf der Grundlage umfassender Archivrecherchen, welche Interessen dabei aufeinandertrafen und was in den Hinterzimmern besprochen und angebahnt wurde. Mit den Regierungen wandelte sich der Austausch mit Autokratien in Südamerika, Ostasien oder im Ostblock. Durch gesellschaftlichen Protest gewannen Werte und Sanktionen allmählich an Bedeutung. Doch der wirtschaftsorientierte Pragmatismus blieb, wie Frank Bösch anschaulich zeigt, das vorherrschende Muster, das die Geschichte der Bundesrepublik zutiefst prägte.
Dezember 1964: Der kongolesische Ministerpräsident Tschombé wird feierlich in Berlin empfangen. Demonstranten stürmen über die Absperrungen. Den «Mörder von Lumumba» trifft eine Tomate «voll in die Fresse», wie Rudi Dutschke mit Genugtuung notiert. Für Dutschke war dies der «Beginn unserer Kultur-Revolution». Nachdem in den fünfziger Jahren die «Kaiser» aus Iran und Äthiopien bejubelt worden waren, führten in den Sechzigern Proteste von oppositionellen Migranten, antikolonialen Gruppen oder auch von Amnesty International zu einer stärker wertebasierten Diplomatie mit Diktatoren: Handel ja, aber bitte auch Freilassung einzelner Oppositioneller.
Frank Bösch zeigt in seinem glänzend geschriebenen Buch, wie sich in den Jahrzehnten nach dem Nationalsozialismus im Umgang mit Diktaturen wirtschaftliche, politische und zivilgesellschaftliche Interessen zu einem Schlingerkurs verschränkten, dessen Widersprüche und Folgen uns bis heute beschäftigen
Worldtube excision method for intermediate mass ratio inspirals
No full textFuture gravitational wave detectors will be sensitive to signals emitted from binary black hole systems with small mass ratios = 2 /1 ≲ 10−2 . The generation of accurate waveforms for these systems has proven to be a challenging task. In numerical relativity, the computational cost of a simulation grows inversely proportional to the square of the mass ratio which quickly becomes unfeasible. In this thesis, I present a novel approach for the simulation of small mass ratio binary black hole systems that aims to partially alleviate this problem. A spherical region around the smaller black hole is excised from the computational domain and replaced with a perturbative solution of a tidally deformed black hole. This removes the tight grid spacing near the small black hole and thereby the limitations imposed on the time step by the Courant-Friedrich-Lewy condition.
The scheme is tested on the example of a scalar toy model consisting of a point charge orbiting a Schwarzschild black hole. An initial study of this problem was carried out by Dhesi et al. (2021) in 1+1 dimensions. I generalize their method to 3+1 dimensions and present an implementation using the SpECTRE numerical relativity code. The accuracy and efficiency of the simulations are demonstrated for circular geodesic orbits. As a second step, I include the effect of the scalar self-force and present the first implementation of a fully self-consistent evolution for a scalar charge model. By dynamically adjusting the size of the excision region, the simulations are able to model the inspiral, plunge, merger and ringdown of the orbit. I present a series of quasi-circular inspirals and compare the results to an adiabatic approximation, demonstrating that post-adiabatic effects are accurately resolved. Finally, I show how the code can be extended to simulate highly eccentric orbits as well as hyperbolic encounters including direct captures.Gravitationswellen entstehen durch beschleunigte Massen, die Energie in das Raum-Zeit-Kontinuum abstrahlen. Diese Wellen komprimieren und dehnen alles in ihrem Weg um einen winzige Distanz, während sie sich durch das Universum ausbreiten. Nur extrem kompakte Objekte, wie etwa Schwarze Löcher und Neutronensterne, können genug Energie emittieren, um messbare Gravitationswellen zu erzeugen. Die erste Detektion eines solchen Signals erfolgte am 14. September 2015 durch das LIGO Interferometer. Es wurde von zwei verschmelzenden schwarzen Löchern erzeugt, die über eine Milliarden Lichtjahre von unserem Sonnensystem entfernt sind.
Die korrekte Auswertung solcher Messungen setzt voraus, dass die möglichen Signale, auf die der Detektor empfindlich ist, berechnet werden können. Die Dynamik von binären schwarzen Löchern und die emittierte Gravitationswellensignatur sind durch die Einsteingleichungen bestimmt. In der Numerischen Relativitätstheorie (NR) wird die Wellenform eines Systems erzeugt, indem diese Gleichungen auf einem Gitter diskretisiert und dann auf Supercomputern gelöst werden. Diese Berechnungen sind ein wichtiger Beitrag zur aktuellen Bestimmung und Analyse von Gravitationswellen.
Zukünftige Detektoren, wie etwa das Einstein-Teleskop oder LISA, werden in der Lage sein Gravitationswellen von Binärsystemen zu detektieren, die aus zwei schwarzen Löchern von weit unterschiedlichen Massen bestehen. Der Rechenaufwand von NR Simulationen nimmt jedoch stark mit diesem Massenverhältnis zu, sodass derzeitige Methoden nicht in der Lage sind, effizient Wellenformen für solche Systeme zu erstellen. In dieser Dissertation beschreibe ich eine neuen Ansatz, der solche Berechnungen stark beschleunigen soll. Die grundlegende Idee besteht darin, eine Region um das kleinere schwarze Loch aus der Simulation auszuschneiden. In diesem Bereich ist das Gravitationsfeld sehr genau durch die Präsenz des kleinen schwarzen Lochs bestimmt, wohingegen das große schwarze Loch nur sehr geringen Einfluss hat. Eine solche Konfiguration ist mathematisch durch eine \textit{perturbative} Lösung beschrieben. Ich erkläre, wie eine solche Lösung in die ausgeschnittene Region der Simulation eingesetzt werden kann und wie dies den Rechenaufwand reduziert