Error-tolerant calibration of dual sensor probes used in a turbulent wall boundary layer

A computer-aided calibration method for hot film probes is presented which tolerates statistical and some systematic errors, and which allows data evaluation in real-time. Essentially, the velocity is approximated by a power series at each yaw angle and for each sensor. A weighting function minimizes the influences of errors. At measurement time the anemometer voltages are roughly linearized. The digitized voltages are subjected to a combination of iteration and interpolation in order to compute the velocity components. RMS-values of the two velocity components parallel to the wall, u and w, and of their partial derivatives with respect to time in a turbulent wall boundary layer are shown and will be used for comparison.     

Nonrealizable Minimal Vertex Triangulations of Surfaces: Showing Nonrealizability Using Oriented Matroids and Satisfiability Solvers

We show that no minimal vertex triangulation of a closed, connected, orientable 2-manifold of genus 6 admits a polyhedral embedding in ℝ³. We also provide examples of minimal vertex triangulations of closed, connected, orientable 2-manifolds of genus 5 that do not admit any polyhedral embeddings. Correcting a previous error in the literature, we construct the first infinite family of such nonrealizable triangulations of surfaces. These results were achieved by transforming the problem of finding suitable oriented matroids into a satisfiability problem. This method can be applied to other geometric realizability problems, e.g., for face lattices of polytopes.     

Inhibition of lipoxygenase pathway improves survival in endotoxin shock

Conclusions The data presented in this paper together with the findings of Hagmann et al. [4] suggest an important role of metabolites of the lipoxygenase pathway in the pathogenesis of endotoxin shock. Selective inhibition of lipoxygenase by FLM 5011 prevented the development of irreversible shock state nearly completely decreasing the mortality rate to 0.05. p ]Further investigations on the precise mechanism of the action of lipoxygenase metabolites are necessary to evaluate their actual significance in the complex pathogenesis of circulatory shock.

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Hemmung des Lipoxygenase-Weges erhöht die Überlebensrate im Endotoxin-Schock

     

Topological configurations exist for all

We show that topological (n₄) point–line configurations exist for all n≥17. It has been proved earlier that they do not exist for n≤16.     

Trajectories of para- and freeomagnetic particles in HGMS filters with axial configurations

The trajectories of para-and ferromagnetic particles with velocities between 0.04 and 2.5 cm s⁻¹ have been investigated in an HGMS model system with axial configuration. A single-wire system has been observed by a TV system. The trajectories were compared with the ideal (inviscid flow) and laminar (viscous flow) model. The results agree with laminar flow model.     

Mikrochemischer Nachweis und Unterscheidung von fünf Tranquilizern aus der Klasse der 5-Phenyl-1,4-Benzodiazepine mit Hilfe der dünnschicht-chromatographischen TRT-Technik

An analysis method for the separation and detection of five 5-phenyl-1,4-benzodiazepines (Chlorazepate, Chlordiazepoxid, Diazepam, Medazepam, Nitrazepam) is described. After separation in the first dimension of two-dimensional thin-layer chromatograms, the benzodiazepines may be converted to benzophenone derivatives by means of treatment with hydrochloric acid. The subsequent separation in the second dimension provides structural information and permits exact specification by way of R_f-values and Bratton-Marshall detection. With this method contents as low as 0.02 μg can be detected.     

Mikrochemischer Nachweis und Unterscheidung von fünf Tranquilizern aus der Klasse der 5-Phenyl-1,4-Benzodiazepine mit Hilfe der dünnschicht-chromatographischen TRT-Technik

An analysis method for the separation and detection of five 5-phenyl-1,4-benzodiazepines (Chlorazepate, Chlordiazepoxid, Diazepam, Medazepam, Nitrazepam) is described. After separation in the first dimension of two-dimensional thin-layer chromatograms, the benzodiazepines may be converted to benzophenone derivatives by means of treatment with hydrochloric acid. The subsequent separation in the second dimension provides structural information and permits exact specification by way of R_f-values and Bratton-Marshall detection. With this method contents as low as 0.02 μg can be detected.     

Penalty alternating direction methods for mixed-integer optimal control with combinatorial constraints

Mathematical Programming - We consider mixed-integer optimal control problems with combinatorial constraints that couple over time such as minimum dwell times. We analyze a lifting and...     

Coherent reflection of he atom beams from rough surfaces at grazing incidence

We report coherent reflection of thermal He atom beams from various microscopically rough surfaces at grazing incidence. For a sufficiently small normal component k(z) of the incident wave vector of the atom the reflection probability is found to be a function of k(z) only. This behavior is explained by quantum reflection at the attractive branch of the Casimir-van der Waals interaction potential. For larger values of k(z) the overall reflection probability decreases rapidly and is found to also depend on the parallel component k(x) of the wave vector. The material specific k(x) dependence for this classic reflection at the repulsive branch of the potential is discussed in terms of an averaging out of the surface roughness under grazing incidence conditions.