Welfare Maximization Entices Participation

We consider randomized mechanisms with optional participation. Preferences over lotteries are modeled using skew-symmetric bilinear (SSB) utility functions, a generalization of classic von Neumann-Morgenstern utility functions. We show that every welfare-maximizing mechanism entices participation and that the converse holds under additional assumptions. Two important corollaries of our results are characterizations of an attractive randomized voting rule that satisfies Condorcet-consistency and entices participation. This stands in contrast to a well-known result by Moulin (1988), who proves that no deterministic voting rule can satisfy both properties simultaneously

The Effects of European Integration on Regional Employment - Specialization of Austrian Regions

This paper focuses on employment effects since Austria joined the European Union. The location of economic activity and thus employment has been of interest for the economics profession for a long time. In this respect the question on the employment effects of integration in common markets is of special interest as the hypothesis can be raised that because of increased competition regions will specialize and industries will concentrate. Therefore it is asked how regions have specialized and how industries have concentrated by using various concentration/specialization measures. Moreover, the role of foreign direct investments are observed in explaining concentration/specialization as well as regional employment shifts. It is shown (i) that no general trends in specialization/concentration can be detected, so that on a general level the hypothesis of joining a common market necessarily leads to specialization/concentration must be refused, but for specific industries and regions interesting patterns can be observed and (ii) foreign direct investments have an significant impact on employment in regions.

Formation of incommensurate long-range magnetic order in the Dzyaloshinskii-Moriya antiferromagnet Ba2_2CuGe2_2O7_7 studied by neutron diffraction

Neutron diffraction on a triple-axis spectrometer and a small-angle neutron scattering instrument is used to study the magnetic phase transition in tetragonal Ba$_2$CuGe$_2$O$_7$ at zero magnetic field. In addition to the incommensurate cycloidal antiferromagnetic (AFM) long-range order, we establish that weak incommensurate ferromagnetism (FM) also arises below the transition temperature $T_N$ identified by sharp Bragg peaks close to the $\Gamma$ point. The intensities of both the incommensurate AFM and FM Bragg peaks vanish abruptly at $T_N$ indicative of a weak first-order transition. Above $T_N$, evidence is presented that the magnetic intensity within the tetragonal $(a,b)$ plane is distributed on a ring in momentum space whose radius is determined by the incommensurate wavevector of the cycloidal order. We speculate that the associated soft fluctuations are at the origin of the weak first-order transition in the spirit of a scenario proposed by Brazovskii.Comment: 10 pages, 4 figure

Water Masers Associated with Star Formation in the Antennae Galaxies

We present Very Large Array observations with 80 milliarcsecond resolution (~9 pc) of the recently discovered Galactic-analog water masers in the Antennae interacting galaxies (NGC 4038/NGC 4039; Arp244). Three regions of water maser emission are detected: two in the ``interaction region'' (IAR) and the third ~5.6'' (> 600 pc) west of the NGC 4039 nucleus. The isotropic water maser luminosities range from 1.3 to 7.7 L_sun. All three maser regions are mostly obscured in the optical/near-infrared continuum, and are coincident with massive CO-identified molecular clouds. The water maser velocities are in excellent agreement with those of the molecular gas. We also present archival VLA 3.6 cm data with ~0.28" (~30 pc) and ~0.8" (~90 pc) resolution toward the maser locations. All three maser regions are coincident with compact 3.6 cm radio continuum emission, and two are dominated by thermal ionized gas, suggesting the presence of natal super star clusters containing the equivalent of a few thousand O stars. We also present detailed comparisons between the radio data and existing HST ACS (optical) and NICMOS (near-IR) data and find that both maser regions in the IAR are also associated with Pa\alpha emission and neither source is detected shortward of 2 microns. These results highlight the potential of using Galactic-analog water masers to pinpoint sites of young super star cluster formation with exquisite angular resolution.Comment: Accepted to ApJ Letters: 14 pages, 2 figure

The Mid-Infrared [SIV]/[NeII] versus [NeIII]/[NeII] Correlation

The mid-infrared ratio [NeIII]15.6mum/[NeII]12.8mum is a strong diagnostic of the ionization state of emission line objects, due to its use of only strong neon emission lines only weakly affected by extinction. However this ratio is not available to ground-based telescopes as only a few spectroscopic windows are available in the MIR. To deal with this problem we aimed to verify if there exists a conversion law between ground-accessible, strong MIR line ratio [SIV]/[NeII] and the diagnostic [NeIII]/[NeII] ratio that can serve as a reference for future ground-based observations. We collated the [SIV]10.5mum, [NeII]12.8mum, [NeIII]15.6\mum and [SIII]18.7mum emission line fluxes from a wide range of sources in the rich Spitzer and ISO archives, and compared the [NeIII]/[NeII], [SIV]/[SIII], and [SIV]/[NeII] ratios. We find a strong correlation between the [SIV]/[NeII] and [\neiii]/[\neii] ratio, with a linear fit of log([NeIII]/[NeII]) = 0.81log([SIV]/[NeII])+0.36, accurate to a factor of ~2 over four orders of magnitude in the line ratios. This demonstrates clearly the ability of ground-based infrared spectrographs to do ionization studies of nebulae.Comment: 5 pages, Accepted for MNRAS letter

Bringing BCI into everyday life: Motor imagery in a pseudo realistic environment

Bringing Brain-Computer Interfaces (BCIs) into everyday life is a challenge because an out-of-lab environment implies the presence of variables that are largely beyond control of the user and the software application. This can severely corrupt signal quality as well as reliability of BCI control. Current BCI technology may fail in this application scenario because of the large amounts of noise, nonstationarity and movement artifacts. In this paper, we systematically investigate the performance of motor imagery BCI in a pseudo realistic environment. In our study 16 participants were asked to perform motor imagery tasks while dealing with different types of distractions such as vibratory stimulations or listening tasks. Our experiments demonstrate that standard BCI procedures are not robust to theses additional sources of noise, implicating that methods which work well in a lab environment, may perform poorly in realistic application scenarios. We discuss several promising research directions to tackle this important problem.BMBF, 01GQ1115, Adaptive Gehirn-Computer-Schnittstellen (BCI) in nichtstationären Umgebunge