Astrochemistry and Astrophotonics for an Antarctic Observatory

Due to its location and climate, Antarctica offers unique conditions for long-period observations across a broad wavelength regime, where important diagnostic lines for molecules and ions can be found, that are essential to understand the chemical properties of the interstellar medium. In addition to the natural benefits of the site, new technologies, resulting from astrophotonics, may allow miniaturised instruments, that are easier to winterise and advanced filters to further reduce the background in the infrared.Comment: 4 pages, to be published in EAS Publications Series, Vol. 40, Proc. of 3rd ARENA conferenc

Konstruktion trifft Design – Das Stuttgarter Modell

Treffen unterschiedliche Welten und Meinungsbilder aufeinander, so sind Missverständnisse und Kommunikationsprobleme unvermeidbar. Während Erstere aus den unterschiedlichen Wissensständen und Randbedingungen resultieren, ergeben sich die Kommunikationsprobleme aus den differenzierten Definitionen und Einstellungen der jeweiligen Fronten. Dieser Umstand lässt sich durch einem Blick auf die Weltgeschichte an vielen, teilweise äußerst dramatischen und einflussreichen Ereignissen leicht belegen. In der Auswirkung deutlich kleiner, aber dennoch nicht unkomplizierter sind aus Missverständnissen und Kommunikationsproblemen resultierende Konflikte im beruflichen Umfeld (Badke-Schaub & Frankberger 2004). Beispiel hierfür ist die Zusammenarbeit von Konstruktion und Design, zweier verwandter aber dennoch verständnisverschiedener Fachdisziplinen, die in der Entwicklung technischer Produkte ihren Ursprung haben. [... aus dem Text

Direct hot embossing of microelements by means of photostructurable polyimide

While automatic hot embossing systems are available for large- and small-scale productions of polymeric devices, one of the process challenges remains to be the manufacturing of precise, durable, and yet inexpensive hot embossing stamps. The use of metallic stamps manufactured by electroplating a photoresist pattern or by precision milling and their replication into silicone molds with UV-lithography, electroplating, and molding techniques is state of the art. Yet, there have been few, if any, thriving attempts to directly emboss polymers by means of bare photoresists, and in particular polyimide-based photoresists, without transferring the photoresist patterns into a different stamp material. We conduct a proof-of-concept by developing hot embossing stamps based on photosensitive polyimide. We focus primarily on the reliability of the aforementioned stamps throughout the hot embossing cycle and the fidelity of pattern transfer onto polymeric films for different microstructural patterns. © 2016 Society of Photo-Optical Instrumentation Engineers (SPIE).DFG/CRC/Planar Optronic System

Dissecting the knee - Air shower measurements with KASCADE

Recent results of the KASCADE air shower experiment are presented in order to shed some light on the astrophysics of cosmic rays in the region of the knee in the energy spectrum. The results include investigations of high-energy interactions in the atmosphere, the analysis of the arrival directions of cosmic rays, the determination of the mean logarithmic mass, and the unfolding of energy spectra for elemental groups

Analyzing Trends in Material Culture Evolution—a Case Study of Gravettian Points from Lower Austria and Moravia

Identifying, analyzing, and explaining trends in the development of material culture is one of the major concerns in prehistoric archaeology. The traditional recording of data in typologies, however, is not optimal for answering the question of diachronic change because typological data capture variability poorly and are often incompatible with multivariate statistics. To overcome these problems, we present PyREnArA (Python-R-Environment for Artifact Analysis), a trait-based tool that allows for a systematic recording of diversity and variability in a way that is applicable to quantitative analysis and multivariate statistics. Using Gravettian assemblages from Lower Austria and Moravia as a case study, we analyze changes in the morphology as well as the design of lithic projectiles and statistically determine the amount of variation that correlates with the progression of time. We identify a slow trend towards slenderer and more pointed projectiles and a shift from laterally to latero-frontally hafted implements. Most of the analyzed traits, however, appear not to experience selective pressure and seem to be unrelated to the passage of time. We discuss these results with regard to different scales of selection, in particular individual choice vs. macroevolutionary group selection over longer periods of time and thus beyond the realm of individual intend, and we raise questions for future research

Operator Projection Theory for Electron Differentiation in Underdoped Cuprate Superconductors

Metals approaching the Mott insulator generate a new hierarchy in the electronic structure accompanied by a momentum dependent electron differentiation, beyond the Mott-Hubbard, Brinkman-Rice and Slater pictures of the Mott transition. To consider such nonlinear phenomenon, we develop an analytic nonperturbative theory based on operator projections combined with a self-consistent treatment of the low-energy excitations. This reproduces the formation of the Hubbard bands, Mott gap, spin fluctuations, mass divergence, diverging charge compressibility, and strongly renormalized flat and damped dispersion similar to angle-resolved photoemission data in high-T_c cuprates. Main structures in electronic spectra show a remarkable similarity to numerical results.Comment: 11 pages, presented at ``Spectroscopies of Novel Superconductors 2001'

The complete genome sequence and comparative genome analysis of the high pathogenicity Yersinia enterocolitica strain 8081

The human enteropathogen, Yersinia enterocolitica, is a significant link in the range of Yersinia pathologies extending from mild gastroenteritis to bubonic plague. Comparison at the genomic level is a key step in our understanding of the genetic basis for this pathogenicity spectrum. Here we report the genome of Y. enterocolitica strain 8081 (serotype 0:8; biotype 1B) and extensive microarray data relating to the genetic diversity of the Y. enterocolitica species. Our analysis reveals that the genome of Y. enterocolitica strain 8081 is a patchwork of horizontally acquired genetic loci, including a plasticity zone of 199 kb containing an extraordinarily high density of virulence genes. Microarray analysis has provided insights into species-specific Y. enterocolitica gene functions and the intraspecies differences between the high, low, and nonpathogenic Y. enterocolitica biotypes. Through comparative genome sequence analysis we provide new information on the evolution of the Yersinia. We identify numerous loci that represent ancestral clusters of genes potentially important in enteric survival and pathogenesis, which have been lost or are in the process of being lost, in the other sequenced Yersinia lineages. Our analysis also highlights large metabolic operons in Y. enterocolitica that are absent in the related enteropathogen, Yersinia pseudotuberculosis, indicating major differences in niche and nutrients used within the mammalian gut. These include clusters directing, the production of hydrogenases, tetrathionate respiration, cobalamin synthesis, and propanediol utilisation. Along with ancestral gene clusters, the genome of Y. enterocolitica has revealed species-specific and enteropathogen-specific loci. This has provided important insights into the pathology of this bacterium and, more broadly, into the evolution of the genus. Moreover, wider investigations looking at the patterns of gene loss and gain in the Yersinia have highlighted common themes in the genome evolution of other human enteropathogens