Der Einfluss der pandemiebedingten Schulschließung auf den Leistungszuwachs von Grundschülerinnen und -schülern in inklusiven Klassen der Schweiz – eine Längsschnittstudie

In der vorliegenden Studie wurde untersucht, ob die achtwöchige Schulschließung in der Schweiz einen Effekt auf den Leistungszuwachs von Grundschüler*innen in inklusiven Klassen in Mathematik und Lesen hatte. Dafür wurde der Leistungszuwachs von zwei Kohorten innerhalb eines Schuljahres verglichen. In Kohorte 1 (n = 728) erfolgte die Leistungsmessung im Schuljahr 2019/20 einige Monate vor und wenige Wochen nach der Schulschließung, in Kohorte 2 (n = 688) erfolgte sie im Schuljahr 2020/2021 vier und zwölf Monate nach der Schulschließung. Es wurde analysiert, ob sich Unterschiede zwischen jüngeren und älteren Lernenden, zwischen Jungen und Mädchen, zwischen Klassen an Schulen mit niedrigem und hohem Sozialindex sowie zwischen Lernenden mit unterschiedlichem Leistungsniveau zeigen. Außerdem wurde untersucht, ob die Wahrnehmung der familiären Lernunterstützung während der Schulschließung sowie die Umsetzung des Distanzunterrichts einen Einfluss auf den Leistungszuwachs hatten. Die Schulschließung hatte einen kleinen negativen Effekt auf die Mathematikleistung der Lernenden der Kohorte 1. Dieser Effekt war in Klassen mit hoher sozialer Belastung größer. Ein stärkerer Einfluss der Schulschließung auf jüngere, auf leistungsschwächere Kinder oder auf Jungen konnte nicht festgestellt werden. Auf die Leseleistung hatte die Schulschließung keinen nachweisbaren Effekt, jedoch hatten Lernende, die während der Schulschließung gut zu Hause lernen konnten, einen größeren Leistungszuwachs im Lesen

Human-Centered Responsible Artificial Intelligence: Current & Future Trends

In recent years, the CHI community has seen significant growth in research on Human-Centered Responsible Artificial Intelligence. While different research communities may use different terminology to discuss similar topics, all of this work is ultimately aimed at developing AI that benefits humanity while being grounded in human rights and ethics, and reducing the potential harms of AI. In this special interest group, we aim to bring together researchers from academia and industry interested in these topics to map current and future research trends to advance this important area of research by fostering collaboration and sharing ideas.Comment: To appear in Extended Abstracts of the 2023 CHI Conference on Human Factors in Computing System

Sugar-sweetened beverages and weight gain in children and adults: a systematic review from 2013 to 2015 and a comparison with previous studies

Objective: Partly inconsistent findings from previous reviews have fueled discussions on the impact of sugar-sweetened beverages (SSBs) on obesity development. The aim was to systematically review the recent evidence in children and adults. Methods: Data were retrieved from the databases MEDLINE, EMBASE, and Cochrane library for the period January 2013 to October 2015. A systematic review of prospective cohort studies and randomized controlled trials (RCTs) relating SSBs to weight measures was conducted. Results: 30 publications met the inclusion criteria. Prospective cohort studies (96%; n = 26) showed a positive association between consumption of SSBs and weight/BMI in adults and children (n = 242,352), and only one cohort study in children showed no association. Findings from three RCTs in children demonstrated that SSB consumption had an effect on BMI/BMI z-score. The one RCT in adults showed no significant effect of the intervention. 63% of the studies were of good, 30% of medium quality, and none was funded by industry. Conclusion: Recent evidence suggests that SSB consumption is positively associated with or has an effect on obesity indices in children and adults. By combining the already published evidence with the new one, we conclude that public health policies should aim to reduce the consumption of SSBs and encourage healthy alternatives such as water. (c) 2017 The Author(s) Published by S. Karger GmbH, Freibur

A Physical Model for the Condensation and Decondensation of Eukaryotic Chromosomes

During the eukaryotic cell cycle, chromatin undergoes several conformational changes, which are believed to play key roles in gene expression regulation during interphase, and in genome replication and division during mitosis. In this paper, we propose a scenario for chromatin structural reorganization during mitosis, which bridges all the different scales involved in chromatin architecture, from nucleosomes to chromatin loops. We build a model for chromatin, based on available data, taking into account both physical and topological constraints DNA has to deal with. Our results suggest that the mitotic chromosome condensation/decondensation process is induced by a structural change at the level of the nucleosome itself

Structural plasticity of single chromatin fibers revealed by torsional manipulation

Magnetic tweezers are used to study the mechanical response under torsion of single nucleosome arrays reconstituted on tandem repeats of 5S positioning sequences. Regular arrays are extremely resilient and can reversibly accommodate a large amount of supercoiling without much change in length. This behavior is quantitatively described by a molecular model of the chromatin 3-D architecture. In this model, we assume the existence of a dynamic equilibrium between three conformations of the nucleosome, which are determined by the crossing status of the entry/exit DNAs (positive, null or negative). Torsional strain, in displacing that equilibrium, extensively reorganizes the fiber architecture. The model explains a number of long-standing topological questions regarding DNA in chromatin, and may provide the ground to better understand the dynamic binding of most chromatin-associated proteins.Comment: 18 pages, 7 figures, Supplementary information available at http://www.nature.com/nsmb/journal/v13/n5/suppinfo/nsmb1087_S1.htm

Nucleosome Chiral Transition under Positive Torsional Stress in Single Chromatin Fibers

Using magnetic tweezers to investigate the mechanical response of single chromatin fibers, we show that fibers submitted to large positive torsion transiently trap positive turns, at a rate of one turn per nucleosome. A comparison with the response of fibers of tetrasomes (the (H3-H4)2 tetramer bound with ~50 bp of DNA) obtained by depletion of H2A-H2B dimers, suggests that the trapping reflects a nucleosome chiral transition to a metastable form built on the previously documented righthanded tetrasome. In view of its low energy, <8 kT, we propose this transition is physiologically relevant and serves to break the docking of the dimers on the tetramer which in the absence of other factors exerts a strong block against elongation of transcription by the main RNA polymerase.Comment: 33 pages (double spacing), 7 figure