Glass shell manufacturing in space

Residual gases always found in glass shells are CO2, O2 and N2. In those cases where high water vapor pressure is maintained in the furnace, water is also found in the shells. Other evidence for the existence of water in shells is the presence of water-induced surface weathering of the interior shell surface. Water and CO2 are the predominant volatiles generated by the pyrolysis of both inorganic and hydrolyzed metal-organic gels. The pyrolysates of unhydrolyzed metal-organic gels also contain, in addition to water and CO2, significant levels of organic volatiles, such as ethanol and some hydrocarbons; on complete oxidation, these produce CO2 and water as well. Water is most likely the initial blowing agent, it is produced copiously during the initial stages of heating. In the later stages, CO2 becomes the dominant gas as H2O is lost at increasing rates. Water in the shell arises mainly from gel dehydration, CO2 by sodium bicarbonate/carbonate decomposition and carbon oxidation, and O2 and N2 by permeation of the ambient furnace air through the molten shell wall

Unterstützung von videobasiertem Unterricht durch Interaktionen - Implementierung eines ersten Prototyps

Videos sind meist reine Konsumationsmedien ohne weitere Interaktion. Aus diesem Grund wird eine Web-Anwendung entwickelt, welche es ermöglicht, verschiedene Formen der Interaktion und Kommunikation während dem Betrachten eines Videos bereitzustellen. Dies soll den Teilnehmerinnen und Teilnehmern helfen, den sogenannten "Berieselungseffekt" zu vermeiden. Die bzw. der Vortragende sollte mit Hilfe der Interaktionen feststellen können, ob die Teilnehmer/innen die Lerninhalte verstehen. Die entwickelte Web-Anwendung bietet unter anderem die Möglichkeit, Multiple-Choice-Fragen zu bestimmten Zeitpunkten in das Video einzubetten. Außerdem stehen viele Analysemöglichkeiten wie zum Beispiel ein genaues Aufmerksamkeitsprofil zur Verfügung. Eine erste Evaluation zeigt eine rege Teilnahme an den Interaktionen. 24.04.2014 | Josef Wachtler & Martin Ebner (Graz

Teaching Tip: developing an intercollegiate Twitter forum to aid student exam study and the development of digital professionalism

#VetFinals has been developed as a novel online Twitter teaching event designed to support intercollegiate veterinary teaching using social media. Previous studies in other fields have suggested that Twitter use within universities may have benefits for undergraduate education. This “teaching tip” paper describes a project using Twitter to host online exam study sessions. The project has been a highly successful collaborative effort between the Royal Veterinary College and Nottingham Veterinary School in the UK. Over 4 years, the #VetFinals project has developed into a long-term, self-sustaining enterprise. This initiative provides a semi-structured means for student exam preparation with direct real-time input from a faculty member. It also creates a network of peers both horizontally across institutions and vertically throughout year groups. Based on similar initiatives in other disciplines, an anticipated outcome of this project was to contribute to student online professionalism. This could help address the veterinary community's recently highlighted problems with professional conduct and appropriate use of social media. Analysis of the success of this endeavor will be available in a future publication

Microwave-induced resistance oscillations in a back-gated GaAs quantum well

We performed effective mass measurements employing microwave-induced resistance oscillation in a tunable-density GaAs/AlGaAs quantum well. Our main result is a clear observation of an effective mass increase with decreasing density, in general agreement with earlier studies which investigated the density dependence of the effective mass employing Shubnikov- de Haas oscillations. This finding provides further evidence that microwave-induced resistance oscillations are sensitive to electron-electron interactions and offer a convenient and accurate way to obtain the effective mass.Comment: 4 pages, 4 figure

Anisotropy in the helicity modulus of a 3D XY-model: application to YBCO

We present a Monte Carlo study of the helicity moduli of an anisotropic classical three-dimensional (3D) XY-model of YBCO in superconducting state. It is found that both the ab-plane and the c-axis helicity moduli, which are proportional to the inverse square of the corresponding magnetic field penetration depth, vary linearly with temperature at low temperatures. The result for the c-axis helicity modulus is in disagreement with the experiments on high quality samples of YBCO. Thus we conclude that purely classical phase fluctuations of the superconducting order parameter cannot account for the observed c-axis electrodynamics of YBCO.Comment: 7 pages, 1 figur

Experiences with iPads in primary schools

Los ordenadores-tablet están acaparando toda la atención en estos momentos y forman parte de nuestra vida cotidiana. Por ello, no es de extrañar que en el ámbito educativo se hayan arbitrado fórmulas para incorporarlos en las aulas. La presente investigación pretende mostrar las estrategias llevadas a cabo en determinadas experiencias con iPads en escuelas primarias austriacas. Por un lado, se describe el desarrollo de las aplicaciones (apps) educativas apropiadas para su empleo en aulas. Y por otro, cada lección apoyada en las tecnologías es analizada y evaluada desde una perspectiva técnica. Las aportaciones más representativas de la investigación evidencian las diversas fórmulas de utilización de este tipo de ordenadores para promover una influencia positiva en la enseñanza, también se apuntan recomendaciones prácticas sobre cómo deberían ser usados en aulasTablet computers gain enormous attention nowadays and become more and more part of our daily life. Due to this it is not astonishing that even the educational sector is thinking about the use of such wearable devices in the classroom. Our research study aims to give insights about real life experiences with iPads in Austrian primary schools. Therefore we describe the development of appropriate learning apps and their use in classrooms. Finally each technology-enhanced lesson is observed as well as evaluated afterwards with the help of the cut-off technique. The research work carries out different circumstances the use of tablet computers has a positive influence on teaching and learning and gives practical hints how they should be used in classrooms.Grupo FORCE (HUM-386). Departamento de Didáctica y Organización Escolar de la Universidad de Granad

A Unifying Splitting Framework

International audienceAVATAR is an elegant and effective way to split clauses in a saturation prover using a SAT solver. But is it refutationally complete? And how does it relate to other splitting architectures? To answer these questions, we present a unifying framework that extends a saturation calculus (e.g., superposition) with splitting and embeds the result in a prover guided by a SAT solver. The framework also allows us to study locking, a subsumption-like mechanism based on the current propositional model. Various architectures are instances of the framework, including AVATAR, labeled splitting, and SMT with quantifiers

Novelty Search in Competitive Coevolution

One of the main motivations for the use of competitive coevolution systems is their ability to capitalise on arms races between competing species to evolve increasingly sophisticated solutions. Such arms races can, however, be hard to sustain, and it has been shown that the competing species often converge prematurely to certain classes of behaviours. In this paper, we investigate if and how novelty search, an evolutionary technique driven by behavioural novelty, can overcome convergence in coevolution. We propose three methods for applying novelty search to coevolutionary systems with two species: (i) score both populations according to behavioural novelty; (ii) score one population according to novelty, and the other according to fitness; and (iii) score both populations with a combination of novelty and fitness. We evaluate the methods in a predator-prey pursuit task. Our results show that novelty-based approaches can evolve a significantly more diverse set of solutions, when compared to traditional fitness-based coevolution.Comment: To appear in 13th International Conference on Parallel Problem Solving from Nature (PPSN 2014

Molecular and immunological characterization of profilin from mugwort pollen

In late summer in Europe, pollen of mugwort is one of the major sources of atopic allergens. No information about the complete molecular structure of any mugwort allergen has been published so far. Here we report the isolation and characterization of mugwort pollen cDNA clones coding for two isoforms of the panallergen profilin. Thirtysix percent of the mugwort allergic patients tested displayed IgE antibodies against natural and recombinant profilin, and no significant differences were observed in the IgEbinding properties of the isoforms. One profilin isoform was purified to homogeneity and detailed structural analysis indicated that the protein exists in solution as dimers and tetramers stabilized by sulfydryl and/or ionic interactions. Profilin monomers were detectable only after exposure of multimers to harsh denaturing conditions. Dimers and tetramers did not significantly differ in their ability to bind serum IgE from mugwort pollenallergic patients. However, oligomeric forms might have a higher allergenic potential than monomers because larger molecules would have additional epitopes for IgEmediated histamine release. Profilin isolated from mugwort pollen also formed multimers. Thus, oligomerization is not an artifact resulting from the recombinant production of the allergen. Inhibition experiments showed extensive IgE crossreactivity of recombinant mugwort profilin and profilin from various pollen and food extracts

Higher Education Landscape 2030

This open access Springer Brief provides a systematic analysis of current trends and requirements in the areas of knowledge and competence in the context of the project “(A) Higher Education Digital (AHEAD)—International Horizon Scanning / Trend Analysis on Digital Higher Education.” It examines the latest developments in learning theory, didactics, and digital-education technology in connection with an increasingly digitized higher education landscape. In turn, this analysis forms the basis for envisioning higher education in 2030. Here, four learning pathways are developed to provide a glimpse of higher education in 2030: Tamagotchi, a closed ecosystem that is built around individual students who enter the university soon after secondary education; Jenga, in which universities offer a solid foundation of knowledge to build on in later phases; Lego, where the course of study is not a monolithic unit, but consists of individually combined modules of different sizes; and Transformer, where students have already acquired their own professional identities and life experiences, which they integrate into their studies. In addition, innovative practice cases are presented to illustrate each learning path