Photo- and Electroproduction of Eta Mesons

Eta photo- and electroproduction off the nucleon is investigated in an effective lagrangian approach that contains Born terms and both vector meson and nucleon resonance contributions. In particular, we review and develop the formalism for coincidence experiments with polarization degrees of freedom. The different response functions appearing in single and double polarization experiments have been studied. We will present calculations for structure functions and kinematical conditions that are most sensitive to details of the lagrangian, in particular with regard to contributions of nucleon resonances beyond the dominant $S_{11}$(1535) resonance.Comment: 24 pages RevTeX/LaTeX2.09, NFSS1, 13 figures (in separate file (tar,gzip and uue)), accepted for publication in Z. Phys.

To Separate or Not to Separate Investment from Commercial Banking? An Empirical Analysis of Attention Distortion Under Multiple Tasks

In the wake of the 2008/2009 financial crisis, a number of policy reports (Vickers, Liikanen, Volcker) proposed to separate investment banking from commercial banking to increase financial stability. This paper empirically examines one theoretical justification for these proposals, namely attention distortion under multiple tasks as in Holmstrom and Milgrom (1991). Universal banks can be viewed as combining two different tasks (investment banking and commercial banking) in the same organization. We estimate pay-performance sensitivities for different segments within universal banks and for pure investment and commercial banks. We show that the pay-performance sensitivity is higher in investment banking than in commercial banking, no matter whether it is organized as part of a universal bank or in a separate institution. Next, the paper shows that relative pay-performance sensitivities of investment and commercial banking are negatively related to the quality of the loan portfolio in universal banks. Depending on the specification, we obtain a reduction in problem loans when investment banking is removed from commercial banks of up to 12 percent. We interpret the evidence to imply that the higher pay-performance sensitivity in investment banking directs the attention of managers away from commercial banking within universal banks, consistent with Holmstrom and Milgrom (1991). Separation of investment banking and commercial banking may indeed be associated with a reduction in risk in commercial banking

The Macroeconomic Effects of the Euro Area's Fiscal Consolidation 2011-2013: A Simulation-Based Approach

We simulate the Euro Area's fiscal consolidation between 2011 and 2013 by employing two DSGE models used by the ECB and the European Commission, respectively. The cumulative multiplier amounts to 0.7 and 1.0 in the baseline, but increases to 1.3 with a reasonably calibrated financial accelerator and a crisis-related increase of the share of liquidity constrained households. In the latter scenario, fiscal consolidation would be largely responsible for the decline in the output gap from 2011-2013. Postponing the fiscal consolidation to a period of unconstrained monetary policy (until after the economic recovery) would have avoided most of these losses.Wir simulieren die Haushaltskonsolidierung im Euroraum im Zeitraum 2011 bis 2013 mit Hilfe von zwei DSGE Modellen der EZB und der Europäischen Kommission. Der kumulative Multiplikator beträgt 0.7 bzw. 1.0 in der Basislinie, steigt aber auf 1.3, wenn die Modelle um einen plausibel kalibrierter Finanzakzelerator erweitert und der Anteil liquiditätsbeschränkter Haushalte krisenbedingt erhöht wird. Im letzteren Szenario trägt die Haushaltskonsolidierung die maßgebliche Verantwortung für die Verschlechterung der Produktionslücke im Zeitraum 2011 bis 2013. Wäre die Haushaltskonsolidierung erst in einer Phase mit uneingeschränktem geldpolitischen Handlungsspielraum vorgenommen worden (d.h. nach der Erholung der Wirtschaft) hätte der Großteil der BIP-Verluste verhindert werden können

Synapsin- and Actin-Dependent Frequency Enhancement in Mouse Hippocampal Mossy Fiber Synapses

The synapsin proteins have different roles in excitatory and inhibitory synaptic terminals. We demonstrate a differential role between types of excitatory terminals. Structural and functional aspects of the hippocampal mossy fiber (MF) synapses were studied in wild-type (WT) mice and in synapsin double-knockout mice (DKO). A severe reduction in the number of synaptic vesicles situated more than 100 nm away from the presynaptic membrane active zone was found in the synapsin DKO animals. The ultrastructural level gave concomitant reduction in F-actin immunoreactivity observed at the periactive endocytic zone of the MF terminals. Frequency facilitation was normal in synapsin DKO mice at low firing rates (∼0.1 Hz) but was impaired at firing rates within the physiological range (∼2 Hz). Synapses made by associational/commissural fibers showed comparatively small frequency facilitation at the same frequencies. Synapsin-dependent facilitation in MF synapses of WT mice was attenuated by blocking F-actin polymerization with cytochalasin B in hippocampal slices. Synapsin III, selectively seen in MF synapses, is enriched specifically in the area adjacent to the synaptic cleft. This may underlie the ability of synapsin III to promote synaptic depression, contributing to the reduced frequency facilitation observed in the absence of synapsins I and II

Self-productivity and complementarities in human development : evidence from MARS

This paper investigates the role of self-productivity and home resources in capability formation from infancy to adolescence. In addition, we study the complementarities between basic cognitive, motor and noncognitive abilities and social as well as academic achievement. Our data are taken from the Mannheim Study of Children at Risk (MARS), an epidemiological cohort study following the long-term outcome of early risk factors. Results indicate that initial risk conditions cumulate and that differences in basic abilities increase during development. Self-productivity rises in the developmental process and complementarities are evident. Noncognitive abilities promote cognitive abilities and social achievement. There is remarkable stability in the distribution of the economic and socio-emotional home resources during the early life cycle. This is presumably a major reason for the evolution of inequality in human development

The Impact of Social Support Networks on Maternal Employment: A Comparison of West German, East German and Migrant Mothers of Pre-School Children

Given shortages in public child care in Germany, this paper asks whether social support with child care and domestic work by spouses, kin and friends can facilitate mothers' return to full-time or part-time positions within the first six years after birth. Using SOEP data from 1993-2009 and event history analyses for competing risks, the author compares the employment transitions of West German, East German and migrant mothers of pre-school children. The results indicate that West German and migrant mothers return to work sooner if they have access to kin, and that kinship support is particularly important when public child care is unavailable. Furthermore, West German and migrant mothers are more likely to work full-time if their spouses partipate in domestic work. In contrast, social support does not affect employment transitions in East Germany where public child care is more easily accessible and continuous female employment is a prevalent social norm

K0S and Λ production in Pb-Pb collisions at sNN−−−−√=2.76 TeV

The ALICE measurement of K0S and Λ production at midrapidity in Pb-Pb collisions at sNN−−−√=2.76  TeV is presented. The transverse momentum (pT) spectra are shown for several collision centrality intervals and in the pT range from 0.4  GeV/c (0.6  GeV/c for Λ) to 12  GeV/c. The pT dependence of the Λ/K0S ratios exhibits maxima in the vicinity of 3  GeV/c, and the positions of the maxima shift towards higher pT with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate pT is not observed in pp interactions at s√=0.9  TeV and at s√=7  TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured pT spectra above 2  GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of pT, models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the pT dependence of the Λ/K0S ratio

Hypertriton Production in p-Pb Collisions at √sNN = 5.02 TeV

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of ${\rm ^{3}_{\Lambda}\rm H}$ in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV is presented in this Letter. Its production yield measured in the rapidity interval -1 < y < 0 for the 40% highest multiplicity p-Pb collisions is ${\rm d} N /{\rm d} y =[\mathrm{6.3 \pm 1.8 (stat.) \pm 1.2 (syst.) ] \times 10^{-7}}$. The measurement is compared with the expectations of statistical hadronisation and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in small collision systems such as p-Pb and therefore the measurement of ${\rm d} N /{\rm d} y$ is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6$\sigma$ of some configurations of the statistical hadronisation, thus constraining the production mechanism of loosely bound states