A dichotomy in dust-jet orientation in radio galaxies

We have analyzed the position angle (PA) differences between radio jets and dust distributions in the centers of Fanaroff & Riley Type 1 (FRI) radio galaxies. We model the observed PA differences to infer the three-dimensional relative orientation of jet and dust. Our main conclusion is that there is a dichotomy in dust-jet-galaxy orientation both in projection and in three-dimensional space. The orientation dichotomy can explain the contradictory results obtained in previous studies. We briefly mention scenarios that might explain the dichotomy.Comment: 2 pages, 2 figures, to appear in "The Interplay among Black Holes, Stars and ISM in Galactic Nuclei", IAU Symposium 222, eds. Th. Storchi Bergmann, L.C. Ho & H.R. Schmit

Clearing price distributions in call auctions

We propose a model for price formation in financial markets based on clearing of a standard call auction with random orders, and verify its validity for prediction of the daily closing price distribution statistically. The model considers random buy and sell orders, placed following demand- and supply-side valuation distributions; an equilibrium equation then leads to a distribution for clearing price and transacted volume. Bid and ask volumes are left as free parameters, permitting possibly heavy-tailed or very skewed order flow conditions. In highly liquid auctions, the clearing price distribution converges to an asymptotically normal central limit, with mean and variance in terms of supply/demand-valuation distributions and order flow imbalance. By means of simulations, we illustrate the influence of variations in order flow and valuation distributions on price/volume, noting a distinction between high- and low-volume auction price variance. To verify the validity of the model statistically, we predict a year's worth of daily closing price distributions for 5 constituents of the Eurostoxx 50 index; Kolmogorov-Smirnov statistics and QQ-plots demonstrate with ample statistical significance that the model predicts closing price distributions accurately, and compares favourably with alternative methods of prediction

Superconformal hypermultiplets

We present theories of N=2 hypermultiplets in four spacetime dimensions that are invariant under rigid or local superconformal symmetries. The target spaces of theories with rigid superconformal invariance are (4n)-dimensional {\it special} hyper-K\"ahler manifolds. Such manifolds can be described as cones over tri-Sasakian metrics and are locally the product of a flat four-dimensional space and a quaternionic manifold. The latter manifolds appear in the coupling of hypermultiplets to N=2 supergravity. We employ local sections of an Sp$(n)\times{\rm Sp}(1)$ bundle in the formulation of the Lagrangian and transformation rules, thus allowing for arbitrary coordinatizations of the hyper-K\"ahler and quaternionic manifolds

Verslechtering ruilvoet leidt tot lager inkomen agrarische sector

Sterke prijsstijgingen van een aantal belangrijke kostenfactoren hebben samen met lagere prijzen in de plantaardige sector geleid tot een verslechtering van de ruilvoet binnen de totale agrarische sector. De toename van de productiewaarde blijft ver achter bij die van de productiekosten. Toegevoegde waarde en inkomen dalen sterk