68 research outputs found
Authentizität mathematischer Modellierungsaufgaben in standardisierten Testsituationen
Es besteht ein Konsens darüber, dass Modellierung und Realitätsbezüge im Mathematikunterricht eine wichtige Rolle spielen. In diesem Zusammenhang wird in der deutschen Mathematikdidaktik seit vielen Jahren die Forderung nach Authentizität in Mathematikaufgaben formuliert (siehe beginnend bei Kaiser-Meßmer, 1993, bis Greefrath, 2018). Dabei sind sowohl Begriff als auch das auf diesem bestehende Konstrukt regelmäßig Gegenstand von Diskussionen, beide werden oftmals nicht klar/ einheitlich definiert und unterschiedlich interpretiert. Einen bedeutsamen Einfluss auf den aktuellen Diskurs haben hier in den letzten Jahren die theoretischen Überlegungen von Vos (2011, 2018). Auf diesen aufbauend soll daher in der vorliegenden qualitativen Studie untersucht werden, inwieweit der von Vos formulierte Ansatz zur Analyse und Kategorisierung mathematischen Modellierungsaufgaben im Allgemeinen auch auf Modellierungsaufgaben in standardisierten Testsituationen übertragen werden kann und welche Konsequenzen sich hieraus für die Operationalisierung solcher Aufgaben ableiten lassen. Im Folgenden werden zunächst zentrale theoretische Ideen zur Authentizität (beim mathematischen Modellieren) skizziert und anschließend das Forschungsinteresse, Methode und erwartete Ergebnisse vorgestellt
Stiripentol fails to lower plasma oxalate in a dialysis-dependent PH1 patient
Background: Primary hyperoxaluria type 1 (PH1) is a multisystemic metabolic disorder caused by an excessive production of oxalate by the liver. The majority of patients presenting in early infancy have end-stage renal disease (ESRD). While awaiting the results of sRNAi trials, the current standard treatment is combined liver-kidney transplantation. Recently, Stiripentol has been reported as a promising drug in the treatment of primary hyperoxaluria by reducing urinary oxalate (UOx). Stiripentol is an anti-convulsive drug used in the treatment of children suffering from Dravet syndrome. It causes blockage of the last step in oxalate production by inhibition of hepatic lactate dehydrogenase 5 (LDH5).
Case: We administered Stiripentol as compassionate use in an anuric infant with dialysis-dependent PH1 over a period of 4 months. Although achieving plasma concentrations of Stiripentol that were recently reported to lower UOx excretion, we did not observe significant reduction to plasma oxalate concentrations (POx).
Conclusion: We conclude that Stiripentol may not be useful to reduce POx in PH patients with advanced chronic kidney disease (CKD), but larger studies are needed to confirm this finding
Fachdidaktisches Design von Begründungsvideos im Projekt studiVEMINTvideos
Im Projekt studiVEMINTvideos werden seit Oktober 2019 mathematische Lernvideos zur Unterstützung von Studierenden beim Übergang in die Hochschule erstellt. Diese ergänzen den vorhandenen E Learning-Kurs studiVEMINT (http://go.upb.de/studivemint), der für das selbstständige Wiederholen der Schulmathematik oder das neue Lernen schulmathematischer Inhalte, die nicht mehr oder nur randständig in der Schule behandelt werden, aber für den Start an der Hochschule wichtig sind, entwickelt wurde. Dabei geht es auch um Aufbereitung der Schulmathematik im Hinblick auf die Verwendung in der Hochschule, was etwas formalere Darstellungen und adäquatere Begründungen als in der Mathematik in der Schule beinhaltet. Der Kurs umfasst 13 Lerneinheiten mit für alle mathematikhaltigen Studiengänge relevanten Inhalten. studiVEMINTvideos ist ein Kooperationsprojekt der Universität Paderborn und der Technischen Hochschule Köln und wird bis September 2022 vom Ministerium für Kultur und Wissenschaft des Landes NRW gefördert. Im vorliegenden Beitrag wird exemplarisch anhand des Videotyps Begründungsvideo die Konzeption der Lernvideos genauer vorgestellt und an einem Beispiel illustriert
Increasing the reuse of wood in bulky waste using artificial intelligence and imaging in the VIS, IR, and terahertz ranges
Bulky waste contains valuable raw materials, especially wood, which accounts for around 50% of the volume. Sorting is very time-consuming in view of the volume and variety of bulky waste and is often still done manually. Therefore, only about half of the available wood is used as a material, while the rest is burned with unsorted waste. In order to improve the material recycling of wood from bulky waste, the project ASKIVIT aims to develop a solution for the automated sorting of bulky waste. For that, a multi-sensor approach is proposed including: (i) Conventional imaging in the visible spectral range; (ii) Near-infrared hyperspectral imaging; (iii) Active heat flow thermography; (iv) Terahertz imaging. This paper presents a demonstrator used to obtain images with the aforementioned sensors. Differences between the imaging systems are discussed and promising results on common problems like painted materials or black plastic are presented. Besides that, pre-examinations show the importance of near-infrared hyperspectral imaging for the characterization of bulky waste
Galactic Core-Collapse Supernovae at IceCube: “Fire Drill” Data Challenges and follow-up
The next Galactic core-collapse supernova (CCSN) presents a once-in-a-lifetime opportunity to make astrophysical measurements using neutrinos, gravitational waves, and electromagnetic radiation. CCSNe local to the Milky Way are extremely rare, so it is paramount that detectors are prepared to observe the signal when it arrives. The IceCube Neutrino Observatory, a gigaton water Cherenkov detector below the South Pole, is sensitive to the burst of neutrinos released by a Galactic CCSN at a level >10σ. This burst of neutrinos precedes optical emission by hours to days, enabling neutrinos to serve as an early warning for follow-up observation. IceCube\u27s detection capabilities make it a cornerstone of the global network of neutrino detectors monitoring for Galactic CCSNe, the SuperNova Early Warning System (SNEWS 2.0). In this contribution, we describe IceCube\u27s sensitivity to Galactic CCSNe and strategies for operational readiness, including "fire drill" data challenges. We also discuss coordination with SNEWS 2.0
All-Energy Search for Solar Atmospheric Neutrinos with IceCube
The interaction of cosmic rays with the solar atmosphere generates a secondary flux of mesons that decay into photons and neutrinos – the so-called solar atmospheric flux. Although the gamma-ray component of this flux has been observed in Fermi-LAT and HAWC Observatory data, the neutrino component remains undetected. The energy distribution of those neutrinos follows a soft spectrum that extends from the GeV to the multi-TeV range, making large Cherenkov neutrino telescopes a suitable for probing this flux. In this contribution, we will discuss current progress of a search for the solar neutrino flux by the IceCube Neutrino Observatory using all available data since 2011. Compared to the previous analysis which considered only high-energy muon neutrino tracks, we will additionally consider events produced by all flavors of neutrinos down to GeV-scale energies. These new events should improve our analysis sensitivity since the flux falls quickly with energy. Determining the magnitude of the neutrino flux is essential, since it is an irreducible background to indirect solar dark matter searches
TXS 0506+056 with Updated IceCube Data
Past results from the IceCube Collaboration have suggested that the blazar TXS 0506+056 is a potential source of astrophysical neutrinos. However, in the years since there have been numerous updates to event processing and reconstruction, as well as improvements to the statistical methods used to search for astrophysical neutrino sources. These improvements in combination with additional years of data have resulted in the identification of NGC 1068 as a second neutrino source candidate. This talk will re-examine time-dependent neutrino emission from TXS 0506+056 using the most recent northern-sky data sample that was used in the analysis of NGC 1068. The results of using this updated data sample to obtain a significance and flux fit for the 2014 TXS 0506+056 "untriggered" neutrino flare are reported
Recent neutrino oscillation results with the IceCube experiment
The IceCube South Pole Neutrino Observatory is a Cherenkov detector instrumented in a cubic kilometer of ice at the South Pole. IceCube’s primary scientific goal is the detection of TeV neutrino emissions from astrophysical sources. At the lower center of the IceCube array, there is a subdetector called DeepCore, which has a denser configuration that makes it possible to lower the energy threshold of IceCube and observe GeV-scale neutrinos, opening the window to atmospheric neutrino oscillations studies. Advances in physics sensitivity have recently been achieved by employing Convolutional Neural Networks to reconstruct neutrino interactions in the DeepCore detector. In this contribution, the recent IceCube result from the atmospheric muon neutrino disappearance analysis using the CNN-reconstructed neutrino sample are presented and compared to the existing worldwide measurements
Angular dependence of the atmospheric neutrino flux with IceCube data
IceCube Neutrino Observatory, the cubic kilometer detector embedded in ice of the geographic South Pole, is capable of detecting particles from several GeV up to PeV energies enabling precise neutrino spectrum measurement. The diffuse neutrino flux can be subdivided into three components: astrophysical, from extraterrestrial sources; conventional, from pion and kaon decays in atmospheric Cosmic Ray cascades; and the yet undetected prompt component from the decay of charmed hadrons. A particular focus of this work is to test the predicted angular dependence of the atmospheric neutrino flux using an unfolding method. Unfolding is a set of methods aimed at determining a value from related quantities in a model-independent way, eliminating the influence of several assumptions made in the process. In this work, we unfold the muon neutrino energy spectrum and employ a novel technique for rebinning the observable space to ensure sufficient event numbers within the low statistic region at the highest energies. We present the unfolded energy and zenith angle spectrum reconstructed from IceCube data and compare the result with model expectations and previous measurements
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