249 research outputs found
Detailed Analysis of the Ice Surface after Binding of an Insect Antifreeze Protein and Correlation with the Gibbs-Thomson Equation
Art Can (Not) Save The World, You Can – Towards a Better Understanding of Art as Collaborative Action within the Process of Urban and Regional Planning
The region of Eisenerz in the heart of Austria is currently in a state of post-industrial structural change. Migration, abandoned structures, vacancies and shrinking are displacing the centuries-long iron industry boom.
During the Rostfest 2012, an annual art and culture festival that focuses on regional development impacts, the art installation “re-light Eisenerz” was staged in the form of a do-it-yourself water power plant. The energy it generated was used to light an abandoned 18th-century building using LED technology. This joyful project started a dynamic public participation process on the topics of renewable energy production and future cityscapes. It created new perspectives on the city’s resources and a resilient image for the broader region.
The team of oiXplorer is moderating this ongoing art-driven process. Together with local initiatives and citizens the group is currently working on the realization of a prototype, using innovative waterpower technology (gravitation water vortex power plant). The micro-implementation will power the local grid of streetlights and revitalize the vanished industrial water infrastructure of Eisenerz. In this sense, water makes light and light makes community.
In this paper we will, based on our own experiences, discuss the role of art practice related to planning culture. We pose the question of whether art does not replace urban development, but stimulates and pushes it to the next level. The artist might dig it out, but we all make it happen
Analyse der Eisoberflächenstruktur nach Bindung eines Antigefrierproteins und deren Zusammenhang mit der Gibbs-Thomson Gleichung
Antigefrieproteine (AFP) sind durch ihre Oberflächenbindung an Eiskristalle in der Lage, das Eiskristallwachstum und den Rekristallisationsprozess aufgrund des Gibbs-Thomson-Effekts zu beeinflussen. Die Bindung der AFP führt zur Bildung einer gekrümmten Eisoberfläche und es wird allgemein angenommen, dass es einen kritischen Eiskristallradius zwischen den Proteinen auf der Eisoberfläche gibt, der die maximale thermische Hysterese bestimmt. In dieser Arbeit wird mit Hilfe von Molekulardynamiksimulationen (MD) die resultierende dreidimensionale Oberflächenstruktur eines Eiskristalls unter Bindung eines AFP (spruce budworm AFP [1]) analysiert und die Lage des kritischen Radius ermittelt. Im Gegensatz zu früheren Erwartungen aus der Literatur konnten wir zeigen, dass sich der kritische Radius nicht direkt zwischen den adsorbierten Proteinen befindet. Darüber hinaus haben wir gezeigt, dass die minimale Temperatur, bei der das System nicht einfriert, sehr gut mit dem mit der Gibbs-Thomson-Gleichung berechneten Wert am kritischen Radius übereinstimmt, sofern dynamische Systembedingungen berücksichtigt werden. Dies beweist zum einen, dass der Gibbs-Thomson-Effekt die Grundlage der Eiskristallwachstumsbehinderung ist und dass MD-Simulationen für die Vorhersage der Schmelzpunktsenkung durch AFP geeignet sind [2]. Die gewonnenen Erkenntnisse sollen in zukünftigen Arbeiten auf andere Moleküle und Lösungen übertragen werden.
[1] Graether SP, Kuiper MJ, Gagné SM, Walker VK, Jia Z, Sykes BD, Davies PL. Betahelix structure and ice-binding properties of a hyperactive antifreeze protein from an insect. Nature. 2000 Jul 20;406(6793):325-8. doi: 10.1038/35018610. PMID:10917537.
[2] Gerhäuser J, Gaukel V. Detailed Analysis of the Ice Surface after Binding of an Insect Antifreeze Protein and Correlation with the Gibbs-Thomson Equation. Langmuir. 2021 Sep 29. doi: 10.1021/acs.langmuir.1c01620. Epub ahead of print. PMID:34585573
Modification of intergrain connectivity, upper critical field anisotropy, and critical current density in ion irradiated MgB2 films
We study the effect of 100 MeV Silicon and 200 MeV Gold ion irradiation on
the inter and intra grain properties of superconducting thin films of Magnesium
Diboride. Substantial decrease in inter-grain connectivity is observed,
depending on irradiation dose and type of ions used. We establish that
modification of sigma band scattering mechanism, and consequently the upper
critical field and anisotropy, depends on the size and directional properties
of the extrinsic defects. Post heavy ion irradiation, the upper critical field
shows enhancement at a defect density that is five orders of magnitude less
compared to neutron irradiation. The critical current density however is best
improved through light ion irradiation.Comment: 18 pages, 4 figures, submitte
Intrinsic Tunneling in Cuprates and Manganites
The most anisotropic high temperature superconductors like Bi2Sr2CaCu2O8, as
well as the recently discovered layered manganite La1.4Sr1.6Mn2O7 are layered
metallic systems where the interlayer current transport occurs via sequential
tunneling of charge carriers. As a consequence, in Bi2Sr2CaCu2O8 adjacent CuO2
double layers form an intrinsic Josephson tunnel junction while in in
La1.4Sr1.6Mn2O7 tunneling of spin polarized charge carriers between adjacent
MnO2 layers leads to an intrinsic spin valve effect. We present and discuss
interlayer transport experiments for both systems. To perform the experiments
small sized mesa structures were patterned on top of single crystals of the
above materials defining stacks of a small number of intrinsic Josephson
junctions and intrinsic spin valves, respectively.Comment: 6 pages, 8 figure
Modulation of Adipocyte Differentiation and Proadipogenic Gene Expression by Sulforaphane, Genistein, and Docosahexaenoic Acid as a First Step to Counteract Obesity
Obesity is characterized by excess body fat accumulation due to an increase in the size and number of differentiated mature adipocytes. Adipocyte differentiation is regulated by genetic and environmental factors, and its inhibition could represent a strategy for obesity prevention and treatment. The current study was designed with two aims: (i) to evaluate the changes in the expression of adipogenic markers (C/EBPα, PPARγ variant 1 and variant 2, and GLUT4) in 3T3-L1 murine preadipocytes at four stages of the differentiation process and (ii) to compare the effectiveness of sulforaphane, genistein, and docosahexaenoic acid in reducing lipid accumulation and modulating C/EBPα, PPARγ1, PPARγ2, and GLUT4 mRNA expression in mature adipocytes. All bioactive compounds were shown to suppress adipocyte differentiation, although with different effectiveness. These results set the stage for further studies considering natural food constituents as important agents in preventing or treating obesity
Columnar defects and vortex fluctuations in layered superconductors
We investigate fluctuations of Josephson-coupled pancake vortices in layered
superconductors in the presence of columnar defects. We study the
thermodynamics of a single pancake stack pinned by columnar defects and obtain
the temperature dependence of localization length, pinning energy and critical
current. We study the creep regime and compute the crossover current between
line-like creep and pancake-like creep motion. We find that columnar defects
effectively increase interlayer Josephson coupling by suppressing thermal
fluctuations of pancakes. This leads to an upward shift in the decoupling line
most pronounced around the matching field.Comment: 5 pages, REVTeX, no figure
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