Evaluierung des flexiblen Lernbedarfs bei Studierenden – Implikationen für die Praxis

In der vorliegenden Evaluationsstudie wurden Studierende und Lehrende einer österreichischen Universität befragt, in welchen Bereichen der Lehre sich Studierende eine stärkere Flexibilisierung wünschen und inwieweit sich diese Wünsche von der Einschätzung Lehrender unterscheiden. Die Ergebnisse zeigen, dass Studierende und Lehrende in ihren Präferenzen zur Lehrveranstaltungsgestaltung zum großen Teil übereinstimmen, sich aber auch in einzelnen Bereichen unterscheiden. Insbesondere hinsichtlich einzelner Aspekte von Zeit, Inhalt, Lernressourcen und Support, Beurteilung und Bereitstellung schätzen Studierende Flexibilität bedeutsamer ein als Lehrende. Es zeigen sich hier bedeutsame statistische Effekte

Fairness als zentrale Herausforderung moderner Aufnahmeverfahren

In der Praxis wird zumeist angenommen, dass die Ergebnisse in einem Aufnahmeverfahren individuelle Unterschiede in den zu erfassenden Fähigkeiten fair messen. Der vorliegende Beitrag gibt einen Überblick über Modelle zur Fairness von Aufnahmeverfahren und deren Überprüfung in der Praxis anhand von Beispielen zum Aufnahmeverfahren für Medizinische Studiengänge in Österreich (MedAT). Der Beitrag arbeitet zudem auch den engen Zusammenhang zwischen Fairness und anderen Gütekriterien heraus und veranschaulicht die Vorteile einer stark theoriegeleiteten automatischen Itemgenerierung (AIG), um auf die erhöhten Qualitätsanforderungen bei modernen Aufnahmeverfahren reagieren zu können

Cryo-EM of human Arp2/3 complexes provides structural insights into actin nucleation modulation by ARPC5 isoforms

The Arp2/3 complex regulates many cellular processes by stimulating formation of branched actin filament networks. Because three of its seven subunits exist as two different isoforms, mammals produce a family of Arp2/3 complexes with different properties that may be suited to different physiological contexts. To shed light on how isoform diversification affects Arp2/3 function, we determined a 4.2 Å resolution cryo-EM structure of the most active human Arp2/3 complex containing ARPC1B and ARPC5L, and compared it with the structure of the least active ARPC1A-ARPC5-containing complex. The architecture of each isoform-specific Arp2/3 complex is the same. Strikingly, however, the N-terminal half of ARPC5L is partially disordered compared to ARPC5, suggesting that this region of ARPC5/ARPC5L is an important determinant of complex activity. Confirming this idea, the nucleation activity of Arp2/3 complexes containing hybrid ARPC5/ARPC5L subunits is higher when the ARPC5L N-terminus is present, thereby providing insight into activity differences between the different Arp2/3 complexes

PITX2 Modulates Atrial Membrane Potential and the Antiarrhythmic Effects of Sodium-Channel Blockers.

BACKGROUND: Antiarrhythmic drugs are widely used to treat patients with atrial fibrillation (AF), but the mechanisms conveying their variable effectiveness are not known. Recent data suggested that paired like homeodomain-2 transcription factor (PITX2) might play an important role in regulating gene expression and electrical function of the adult left atrium (LA). OBJECTIVES: After determining LA PITX2 expression in AF patients requiring rhythm control therapy, the authors assessed the effects of Pitx2c on LA electrophysiology and the effect of antiarrhythmic drugs. METHODS: LA PITX2 messenger ribonucleic acid (mRNA) levels were measured in 95 patients undergoing thoracoscopic AF ablation. The effects of flecainide, a sodium (Na(+))-channel blocker, and d,l-sotalol, a potassium channel blocker, were studied in littermate mice with normal and reduced Pitx2c mRNA by electrophysiological study, optical mapping, and patch clamp studies. PITX2-dependent mechanisms of antiarrhythmic drug action were studied in human embryonic kidney (HEK) cells expressing human Na channels and by modeling human action potentials. RESULTS: Flecainide 1 μmol/l was more effective in suppressing atrial arrhythmias in atria with reduced Pitx2c mRNA levels (Pitx2c(+/-)). Resting membrane potential was more depolarized in Pitx2c(+/-) atria, and TWIK-related acid-sensitive K(+) channel 2 (TASK-2) gene and protein expression were decreased. This resulted in enhanced post-repolarization refractoriness and more effective Na-channel inhibition. Defined holding potentials eliminated differences in flecainide's effects between wild-type and Pitx2c(+/-) atrial cardiomyocytes. More positive holding potentials replicated the increased effectiveness of flecainide in blocking human Nav1.5 channels in HEK293 cells. Computer modeling reproduced an enhanced effectiveness of Na-channel block when resting membrane potential was slightly depolarized. CONCLUSIONS: PITX2 mRNA modulates atrial resting membrane potential and thereby alters the effectiveness of Na-channel blockers. PITX2 and ion channels regulating the resting membrane potential may provide novel targets for antiarrhythmic drug development and companion therapeutics in AF

Impact of tunable oligophosphonates on barium sulfate crystallization

Calixarenes can be used as well-defined scaffolds for investigating structure–activity relationships of additives and their impact on crystallization. In this work, we present the crystal growth modification of barium sulfate by p-phosphonic acid calix[n]arenes that vary in size (n = 4, 5, 6, and 8) and thus vary in the size of the internal cavity for the same functionality in the upper rim. The tetrameric, hexameric, and octameric macrocycles induce nanoparticle formation with clear superstructure. In the case of the hexameric calix[6]arene, the initial mesocrystalline superstructure fuses over time to form almost hollow spheres, while the mesocrystals formed in the presence of the tetramer and octamer are stable over an extended period. The pentameric calix[5]arene forms more disordered aggregates of single crystals. Thermogravimetric data shows that a significant proportion of the mass of the barium sulfate-containing solid is the macrocycle, regardless of the choice of macrocycle

Orbit Precision Analysis of Small Man-Made Space Objects in LEO Based on Radar Tracking Measurements

The German Space Operations Center (GSOC) performs collision avoidance for 11 LEO and 2 GEO satellites. Risk detection and maneuver decisions strongly depend on the computed probability of collision that is driven by the anticipated orbit precision of chaser and target. While the orbits of operational satellite are well known this is usually not the case for space debris. Therefore, an improved collision assessment requires refined orbit determination of the chaser object. This paper describes the achievable orbit precision for a small object based on radar measurements. The Tracking and Imaging Radar (TIRA) of Fraunhofer FHR in Wachtberg, Germany, was used to track the Canadian nanosatellite CanX-2 over a period of five days. CanX-2 is a triple CubeSat of the size 10x10x34 cm carrying a dual frequency GPS receiver. A reference trajectory is established by precise orbit determination (POD) from GPS measurements. Radar tracking measurements and derived orbital information are evaluated by comparison against the reference orbit. Statistics of the orbit determination and orbit prediction precision using different radar measurement data arc lengths is presented leading to a better understanding of the prediction uncertainty of critical close approaches between an active satellite and a small object

Need Help? Recommending Social Care Institutions

In this paper, we present work-in-progress on a recommender system designed to help people in need find the best suited social care institution for their personal issues. A key requirement in such a domain is to assure and to guarantee the person's privacy and anonymity in order to reduce inhibitions and to establish trust. We present how we aim to tackle this barely studied domain using a hybrid content-based recommendation approach. Our approach leverages three data sources containing textual content, namely (i) metadata from social care institutions, (ii) institution specific FAQs, and (iii) questions that a specific institution has already resolved. Additionally, our approach considers the time context of user questions as well as negative user feedback to previously provided recommendations. Finally, we demonstrate an application scenario of our recommender system in the form of a real-world Web system deployed in Austria.Published at RSBDA Workshop co-located with i-know 201

Open Intrauterine Fetal Myelomeningocele Repair: Changes in the Surgical Procedure and Perinatal Complications during the First 8 Years of Experience at a Single Center

INTRODUCTION Open fetal myelomeningocele (fMMC) repair is nowadays a therapeutic option in selected cases. We aimed to evaluate changes in maternal and fetal outcome after fMMC repair during the first 8 years of experience at a tertiary referral fetal medicine center in Switzerland. -Materials and Methods: Between 2010 and 2018, fMMC repair and delivery of the neonate via planned cesarean section was performed in 67 cases. Cases were retrospectively stratified into 2 groups: a "training phase" (TP) with supervision from an external surgeon during 11 operations (2010-2014, 15 cases) followed by an "experienced phase" (EP, 2014-2018, 52 cases); each phase lasted about 4 years. Both phases were compared with regard to various maternal and fetal outcome parameters. RESULTS Analyses did not reveal differences between TP and EP in major outcome parameters such as gestational age at delivery, chorionic membrane separation, or the incidence of placental abruption. Although more complex surgical techniques were applied in EP (e.g., dermal closure using a rotational flap), surgery time was not different from TP. At the same time, surgical complications such as oligohydramnios (27 vs. 8%, p = 0.046) with MRI-confirmed leakage (13 vs. 4%, nonsignificant) and subchorionic hematoma (20 vs. 2%, p = 0.009) were less common in EP than TP. CONCLUSIONS This study shows that the level of competence at our center with regard to major perinatal outcome parameters was already high in the first years of fMMC repair. However, more complex surgical techniques and significantly less minor complications were observed during the most recent years