Generierung von Mastzellen aus humanen induzierten pluripotenten Stammzellen: eine neue Strategie zur Untersuchung Mastzell-vermittelter Erkrankungen

Mast cells (MCs) are well known for their contribution to the pathogenesis of a multitude of inflammatory diseases, such as urticaria and mastocytosis. Growing evidence also suggests that MCs exert important surveillance and host-protective functions by orchestrating immune responses. In principle, in vitro studies of MC functions are performed with human MCs isolated from tissues or differentiated from hematopoietic progenitors. However, the recent in vitro research has taken on some challenges including donor-dependent heterogeneity, poor proliferation capacities of primary MCs, and the lack of a continuous cell source. To address this, we developed a novel strategy for the rapid differentiation of MCs from human induced pluripotent stem cells (hiPSC-MCs). hiPSC-MCs exhibit phenotypic and functional characteristics of human skin MCs (hsMCs) and peripheral hematopoietic stem cell-derived MCs (PSCMCs). hiPSC-MCs are able to express the MC-associated receptors such as CD45, CD117, FcεRIα, CD200R, Siglec-8 and MRGPRX2, and degranulate in response to IgE/anti-IgE and substance P. hiPSCs are immortal cells and able to develop into any type of human body cells, thus, for in vitro MCs research, hiPSC lines provide a continuous and stable MC source and overcome the obstacles caused by tissue samples and donor variabilities. In addition, hiPSCs allow for the development of cell models by generating hiPSC-MCs from patients.Mastzellen (MCs) sind bekannt für ihren Beitrag zur Pathogenese einer Vielzahl von entzündlichen Erkrankungen wie Urtikaria und Mastozytose. Immer mehr Hinweise deuten darauf hin, dass MCs wichtige Überwachungs- und Schutzfunktionen ausüben, indem sie Immunantworten modulieren. Um ihre biologischen Funktionen in vitro zu untersuchen, werden humane MCs entweder als reife Zellen aus humanen Geweben wie Haut, Lunge und Darm isoliert oder aus hämatopoetischen Vorläuferzellen aus peripherem oder Nabelschnurblut differenziert. Diese Techniken bergen jedoch mehrere Nachteile und Herausforderungen, darunter eine geringe Proliferationskapazität, eine Spender-abhängige Heterogenität und das Fehlen einer kontinuierlichen Zellquelle. Ziel dieses Projekts war die Entwickelung einer neuartigen Strategie zur schnellen und effizienten Differenzierung von MCs aus humanen induzierten pluripotenten Stammzellen (hiPSC). Diese aus hiPSCs generierten MCs (hiPSC-MCs) weisen phänotypische und funktionelle Eigenschaften von primären humanen Hautmastzellen (hsMC) und Mastzellen, die aus peripheren hämatopoetischen Stammzellen generiert wurden (PSCMCs), auf. hiPSC-MCs zeigen eine stabile Expression typischer MC-assoziierter Rezeptoren wie CD45, CD117, FcεRIα, CD200R, Siglec-8 und MRGPRX2, und degranulieren als Reaktion auf eine Stimulation mit IgE/Anti-IgE und Substanz. P. hiPSCs, reprogrammiert aus menschlichen Körperzellen, bieten aufgrund ihrer Selbsterneuerungseigenschaft eine kontinuierliche und nachhaltige Zellquelle für die Forschung. hiPSC-MCs stellen so einen bedeutenden Fortschritt in Richtung einer schnellen und hochproduktiven Generierung phänotypisch ausgereifter und funktioneller MCs dar und erlauben zudem die Entwicklung krankheitsspezifische Zellmodelle durch die Möglichkeit der hiPSC-MC-Generierung von Patienten

Using Wikis to Support Peer Assessment Activities in Higher Education

This study explored the effectiveness of using wikis as an environment to support peer-assessment in higher education settings. The participants of this study were nineteen per-serviced teachers who enrolled in an undergraduate course on the application of instructional technologies in classroom. In the study, the participants created their personal wiki pages within a course wiki and formed groups of three or four. Five peer-assessment activities were assigned, in which the participants uploaded their class projects to their wiki pages and went to their group member’s pages to provide feedback. The participants were expected to evaluate other’s projects in terms of educational values, visual effects and the format. A short survey was conducted after each activity asking participants’ perceived learning and a post-survey was conducted at the end of the study to ask their general experience of peer-assessment activities in the wiki environment. The survey results and the analysis of participants’ wiki posts indicated that the wiki was an interactive environment that facilitated the peer-assessment effectively. With proper guidance, the participants were able to provide critical peer feedback within the wiki environment

Using Social Annotation Tools to Foster Collaborative Learning

Social annotation (SA) allows learners to highlight and comment on web pages and share annotations with each other online. Despite its potential in promoting collaborative learning, how to integrate it into educational settings has not been fully studied. This study aims at introducing and exploring three different ways of incorporating SA-based activities into an online course: (a) peer review; (b) annotated discussion; and (c) collaborative reading. Students participated all three SA- based activities and took a survey at the end reporting the effectiveness of these activities. In this proposal we reported the initial findings of student participation in the three collaborative learning activities

Capacitance Prediction Using Multi-cascade Convolutional Neural Network for Efficient Wireless Power Transfer

© 2024, IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. This is the accepted manuscript version of a conference paper which has been published in final form at https://doi.org/10.1109/LAWP.2024.3390201The efficiency of the wireless power transfer is significantly impacted by misalignment between the transmitting and receiving coils due to impedance mismatching. To tackle this issue, an efficient power transfer solution is proposed, employing a capacitance prediction method based on a multi-cascade convolutional neural network. In the study, the impedance matching characteristic of a magnetic coupling resonant wireless power transfer system with an impedance matching network is analyzed. After that, a neural network-driven approach is introduced to establish a mapping between reflection impedance and the optimal capacitance, and the impedance matching performance of the system is assessed in the presence of coil misalignments.Peer reviewe

InterTracker: Discovering and Tracking General Objects Interacting with Hands in the Wild

Understanding human interaction with objects is an important research topic for embodied Artificial Intelligence and identifying the objects that humans are interacting with is a primary problem for interaction understanding. Existing methods rely on frame-based detectors to locate interacting objects. However, this approach is subjected to heavy occlusions, background clutter, and distracting objects. To address the limitations, in this paper, we propose to leverage spatio-temporal information of hand-object interaction to track interactive objects under these challenging cases. Without prior knowledge of the general objects to be tracked like object tracking problems, we first utilize the spatial relation between hands and objects to adaptively discover the interacting objects from the scene. Second, the consistency and continuity of the appearance of objects between successive frames are exploited to track the objects. With this tracking formulation, our method also benefits from training on large-scale general object-tracking datasets. We further curate a video-level hand-object interaction dataset for testing and evaluation from 100DOH. The quantitative results demonstrate that our proposed method outperforms the state-of-the-art methods. Specifically, in scenes with continuous interaction with different objects, we achieve an impressive improvement of about 10% as evaluated using the Average Precision (AP) metric. Our qualitative findings also illustrate that our method can produce more continuous trajectories for interacting objects.Comment: IROS 202

Post-positioned gas spring enables ultra-high output power of hybrid thermoacoustic electric generators

High-capacity hybrid thermoacoustic electric generators (HTAEGs) are ideal in different small- and micro-scale energy systems, especially in space nuclear power systems. In this work, an HTAEG with a post-positioned gas spring is proposed. To demonstrate the superiority of the gas-spring-post-positioned design on high-capacity HTAEGs, an HTAEG prototype is modeled, built, and tested from the perspective of thermoacoustics accordingly. Experimental results demonstrate an output electric power of 15.0 kW. Furthermore, it could achieve the highest efficiency of 39.2% with an output electric power of 11.1 kW. Given that a 15-kW power output is an ultra-high level on a single-piston HTAEG of this type to date, and the achieved efficiency on the prototype is also encouraging, this work marks an important milestone in the development of high-capacity HTAEGs. It also demonstrates that the gas-spring-post-positioned design has significant advantages and enormous potential for application

Experimental Investigation on a Linear-compressor Driven Travelling-wave Thermoacoustic Heat Pump

AbstractHeat pump system, offering economical alternatives in recovering waste heat from different sources for using in various industrial, commercial and residential applications, is considered to be a very environmentally-friendly heat and power transfer system. In this paper, to solve the problems of traditional vapour compression heat pump working in unconventional conditions, a novel TWTAHP (travelling-wave thermoacoustic heat pump) is presented to meet the requirement of working in ultra-low temperature. Base on the theoretical simulation and structure optimization, an experimental apparatus for preliminary test has been built, which is only one single independent unit from the whole loop of the TWTAHP system. The results show that the simulation and the testing results were agreeable as expected. Under the -20°C environment temperature and the 50°C heating temperature, we could obtain a maximal COPh (heating COP) of 2.1 and 260W heating capacity for one unit by consuming acoustic power less than 200W. Furthermore, a COPh above 3.0 could be achieved when the ambient temperature was raised to 0°C

Fluorescence quenching determination of iron(III) using rhodamine 6G hydrazide derivative

Department of Education of Fujian Province [JA 09241]; Major Fujian science and technology project [2011YZ0001-1]A fluorescent probe, a rhodamine 6G derivative (R6GD), has been designed and synthesized for the determination of Fe(III). In HAc-NaAc buffer solution, R6GD exhibits highly selective and sensitive response toward Fe(III) based on the fluorescence quenching mechanism of R6GD due to the heavy atom effect of I-3(-) formed in the reaction between KI and Fe(III). Under the optimal conditions, the concentration of Fe(III) showed good linear relationship with the fluorescence intensity change of R6GD. The linear response range of Fe(III) (R-2 = 0.9923) was found from 0.1 to 6.0 mu mol L-1 with the detection limit of 0.05 mu mol L-1 of Fe(III). The recovery of the approach in the determination of Fe(III) in real water samples was 83.3-99.5%