422 research outputs found
Tailored Gires-Tournois etalons as tunable dispersion slope compensators
We present a novel concept of a tailored Gires-Tournois etalon structure and show that such a device is useful for the fabrication of a dispersion-slope compensator with an almost arbitrary dispersion profile and also with tunability in the dispersion slope. © 2004 Optical Society of America
The concept of 'Tragodie' in the work of Gerhart Hauptmann.
This thesis deals with Gerhart Hauptmann's eight. plays which the author himself entitled 'Tragodien'. It examines those characteristics which made Hauptmann call these plays. 'Tragodien' and thus arrives at a definition of his concept of 'Tragodie'. This concept is shown to, be largely inspired by Hauptmann's visit to Greece in 1907. In Greek mythology Hauptmann finds a figurative representation of reality, in which psychological and natural forces are interpreted as aspects of superior, metaphysical powers which determine man's existence. The perpetual conflict between Olympian and chthonic gods mirrors Hauptmann's own view of life as a continual battle between opposing forces of creation and destruction. 'Tragodie' demonstrates' the victory of the destructive forces. Hauptmann's 'Tragodien' show man's helplessness both directly, as destructive forces gain a hold over man's mind by driving him to act on blind impulses, and indirectly, as an atmosphere of menace is built up, in which man feels totally-disorientated, unable to distinguish between illusion and reality. No longer rationally master of his actions, man is driven to commit inhuman acts of cruelty and murder. The portrayal of such inhumanity as the result of superhuman intervention defies man's ability to explain it away rationally. The first four 'Tragodien' have nordic or Germanic settings but in the 'Atridentetralogie' Hauptmann achieves the full power of 'Tragodie' as he conceives it by returning to the Greek source of his inspiration. In this form 'Tragodie' portrays an irruption of the underworld powers of Hades into the light and the sacrifice of human life which this entails. Based on a concept of supernatural, destructive forces, inherent in creation, which threaten human existence, Hauptmann's 'Tragodien' are a remarkable attempt to revive genuine tragedy in an age of rational scepticism
Assessing the continuity of the blue ice climate record at Patriot Hills, Horseshoe Valley, West Antarctica
We use high resolution Ground Penetrating Radar (GPR) to assess the continuity of the Blue Ice Area (BIA) horizontal climate record at Patriot Hills, Horseshoe Valley, West Antarctica. The sequence contains three pronounced changes in deuterium isotopic values at ~18 cal ka, ~12 cal ka and ~8 cal ka. GPR surveys along the climate sequence reveal continuous, conformable dipping isochrones, separated by two unconformities in the isochrone layers, which correlate with the two older deuterium shifts. We interpret these incursions as discontinuities in the sequence, rather than direct measures of climate change. Ice-sheet models and Internal Layer Continuity Index plots suggest that the unconformities represent periods of erosion occurring as the former ice surface was scoured by katabatic winds in front of mountains at the head of Horseshoe Valley. This study demonstrates the importance of high resolution GPR surveys for investigating both paleo-flow dynamics and interpreting BIA climate records
Tunable dispersion slope compensator using novel tailored Gires-Tournois etalons
We present a novel concept of tailored GTE structure and show that such devices are very useful for the realization of DSC with almost arbitrary dispersion profile and also with tunability in dispersion slope
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Nuclear Dbf2-related protein kinases (NDRs) in isolated cardiac myocytes and the myocardium: activation by cellular stresses and by phosphoprotein serine-/threonine-phosphatase inhibitors
The nuclear Dbf2-related protein kinases 1 and 2 (NDR1/2) are closely-related AGC family kinases that are strongly conserved through evolution. In mammals, they are activated inter alia by phosphorylation of an hydrophobic domain threonine-residue [NDR1(Thr-444)/NDR2(Thr-442)] by an extrinsic protein kinase followed by autophosphorylation of a catalytic domain serine-residue [NDR1(Ser-281)/NDR2(Ser-282)]. We examined NDR1/2 expression and regulation in primary cultures of neonatal rat cardiac myocytes and in perfused adult rat hearts. In myocytes, transcripts for NDR2, but not NDR1, were induced by the hypertrophic agonist, endothelin-1. NDR1(Thr-444) and NDR2(Thr-442) were rapidly phosphorylated (maximal in 15-30 min) in myocytes exposed to some phosphoprotein Ser-/Thr-phosphatase 1/2 inhibitors (calyculin A, okadaic acid) and, to a lesser extent, by hyperosmotic shock, low concentrations of H(2)O(2), or chelerythrine. In myocytes adenovirally-transduced to express FLAG-NDR2 (which exhibited a mainly-cytoplasmic localisation), the same agents increased FLAG-NDR2 activity as assessed by in vitro protein kinase assays, indicative of FLAG-NDR2(Ser-282/Thr-442) phosphorylation. Calyculin A-induced phosphorylation of NDR1(Thr-444)/NDR2(Thr-442) and activation of FLAG-NDR2 were inhibited by staurosporine, but not by other protein kinase inhibitors tested. In ex vivo rat hearts, NDR1(Thr-444)/NDR2(Thr-442) were phosphorylated in response to ischaemia-reperfusion or calyculin A. From a pathological viewpoint, we conclude that activities of NDR1 and NDR2 are responsive to cytotoxic stresses in heart preparations and this may represent a previously-unidentified response to myocardial ischaemia in vivo
Interannual surface evolution of an Antarctic blue-ice moraine using multi-temporal DEMs
Multi-temporal and fine resolution topographic data products are increasingly used to quantify surface elevation change in glacial environments. In this study, we employ 3D digital elevation model (DEM) differencing to quantify the topographic evolution of a blue-ice moraine complex in front of Patriot Hills, Heritage Range, Antarctica. Terrestrial laser scanning (TLS) was used to acquire multiple topographic datasets of the moraine surface at the beginning and end of the austral summer season in 2012/2013 and during a resurvey field campaign in 2014. A complementary topographic dataset was acquired at the end of season 1 through the application of Structure-from-Motion with multi-view stereo (SfM-MVS) photogrammetry to a set of aerial photographs acquired from an unmanned aerial vehicle (UAV).Three-dimensional cloud-to-cloud differencing was undertaken using the Multiscale Model to Model Cloud Comparison (M3C2) algorithm. DEM differencing revealed net uplift and lateral movement of the moraine crests within season 1 (mean uplift ~0.10 m), and surface lowering of a similar magnitude in some inter-moraine depressions and close to the current ice margin, although we are unable to validate the latter. Our results indicate net uplift across the site between seasons 1 and 2 (mean 0.07 m). This research demonstrates that it is possible to detect dynamic surface topographical change across glacial moraines over short (annual to intra-annual) timescales through the acquisition and differencing of fine-resolution topographic datasets. Such data offer new opportunities to understand the process linkages between surface ablation, ice flow, and debris supply within moraine ice
Fun with Fibonacci
We introduce a function which measures the number of distinct ways in which a number can be expressed as the sum of Fibonacci numbers. Using a binary table and other devices, we explore the values that can take and reveal some interesting patterns. The article shows how standard spreadsheet functionalities make it possible to reveal quite striking patterns in data, and is intended to be used in the classroom
Another 101 Uses for a Binary Table and a Spreadsheet
The purpose of this paper is to broaden the scope of a previous paper and show applications of a varied nature using the binary table to generate data on which mathematical investigations can be based. Elementary applications considered are the “coins problem”, a binary card trick, Killer Sudoku, and expressing integers in terms of others in specified ways
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