The stress energy tensor of a locally supersymmetric quantum field on a curved spacetime

For an analogon of the free Wess-Zumino model on Ricci flat spacetimes, the relation between a conserved `supercurrent' and the point-separated improved energy momentum tensor is investigated and a similar relation as on Minkowski space is established. The expectation value of the latter in any globally Hadamard product state is found to be a priori finite in the coincidence limit if the theory is massive. On arbitrary globally hyperbolic spacetimes the `supercurrent' is shown to be a well defined operator valued distribution on the GNS Hilbertspace of any globally Hadamard product state. Viewed as a new field, all n-point distributions exist, giving a new example for a Wightman field on that manifold. Moreover, it is shown that this field satisfies a new wave front set spectrum condition in a non trivial way.Comment: 100 pages, PhD Thesis, LaTeX2e + AMS-LaTeX, 5 figures appended as uuencoded ps-file

Yardstick Competition when Quality is Endogenous: The Case of Hospital Regulation

In many countries hospital regulation undergoes fundamental change. In reaction to steadily increasing costs, authorities switch from cost of service regulation to prospective payment systems (PPS). While it seems clear that this new scheme sets strong cost saving incentives, this is not so clear for quality provision. As a matter of fact, everything hinges on the prices the regulator sets. Figuring out optimal prices is, however, a difficult task, be- cause the regulator faces serious informational limitations. The literature largely ignores this problem and points to Shleifer's (1985) yardstick compe- tition for a solution. Yardstick competition, however, ignores quality issues. This paper fills this gap in the literature and shows that endogenizing qual- ity changes the results of yardstick competition substantially. Quality will be zero and cost reduction efforts can be heavily distorted. In general, a simpler version of yardstick competition average cost pricing turns out to be more favorable, though not perfect.Yardstick Competition, Regulation, Hospital Market

Infrared spectroscopy of extraterrestrial material: comparison with astronomical spectra of dust

Infrared spectra of components (CAI, matrix etc.) from type 3 carbonacous chondrites (Allende, Ornans, Vigarano) are compared with infrared spectra from astronomical objects (comets, zodiacal light, circumstellar disks and others)

ER-mitochondria contacts: Actin dynamics at the ER control mitochondrial fission via calcium release.

The formin-like protein INF2 is an important player in the polymerization of actin filaments. In this issue, Chakrabarti et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201709111) demonstrate that INF2 mediates actin polymerization at the endoplasmic reticulum (ER), resulting in increased ER-mitochondria contacts, calcium uptake by mitochondria, and mitochondrial division

Measurements of wall-shear stress fields on the piston crown in an IC engine flow using fluorescent labelled micro-pillar imaging

The measurement of wall shear-stress along the crown of a moving piston is accomplished with an array of hair-like, flexible micro-pillar sensors (MPS) in an internal combustion (IC) engine during intake flow conditions. The MPS are wall-clamped flexible micro-cylinders of 20micron diameter made of polydimethylsiloxane (PDMS) positioned on the surface of a transparent planar piston crown and protruding into the boundary layer flow above the piston at a height of 390micron. Their tips are labelled with fluorophores and are illuminated with a scanning laser-sheet system that follows the piston motion in synchronous manner. The flow-induced deflection is recorded through the transparent piston crown from below with a compact shaft-mounted high-speed camera recording the fluorescent re-emitted light from the pillar tips and using the fact of optical wave-guide features of the transparent micro-pillars. The experiments were performed in a transparent 4-valve engine setup (1.6 liter Prince 2, N13B16) during the intake phase. In order to improve the temporal resolution, the running speed of the engine was scaled down using water as working liquid. A static and dynamic sensor-calibration enabled the precise measurements of the wall-shear stress distribution with the sensor array. Due to spatial resolution limits of current available compact high-speed camera the recorded region along the piston was limited to 4x2 mm2 with 8x4 pillars in full view. The recordings at 300fps show the WSS fluctuations induced by the valve-jet / piston-wall interaction in the beginning of the intake with strong wall-normal motion forming critical points in the WSS field such as saddles, nodes and foci. Over the intake cycle > CA 80° these fluctuations die out and flow is transformed into wall-parallel coherent motion prescribed by the formation of the tumble