2D full waveform inversion of shallow seismic Rayleigh waves

Main objective of this work is the application of 2D full waveform inversion (FWI) to recorded shallow seismic Rayleigh waves. Synthetic studies which are applied in preparation of such an inversion are presented to investigate the significance of different effects (e.g. effects of anelastic damping, influence of P-wave velocity model). Finally, a successful application of 2D FWI to a field dataset acquired on a predominantly depth dependent structure is discussed

On the significance of viscoelasticity in a 2D full waveform inversion of shallow seismic surface waves

We perform two tests to investigate to which degree viscoelastic modeling is relevant during a full waveform inversion of shallow seismic surface waves. Firstly, we compare field data with synthetic elastic and viscoelastic data. We show that the optimized source time function acts as a low pass filter in the case of elastic wavefields and can compensate a significant fraction of the residuals between elasticly and viscoelasticly modeled data. However, the viscoelastic data can explain the recorded data better in some aspects like the amplitude decay with offset of the fundamental mode and the near offset traces. Secondly, we run inversion tests for simulated viscoelastic observations (Q=20) using both elastic as well as viscoelastic forward modeling with Q=20, 25, and 10 during the inversion. The results show that it is not possible to infer the steep gradient in the shear wave velocity model in the topmost meter using an elastic inversion. Using a slightly wrong Q factor in the inversion produces very similar results compared to the results obtained by an inversion using the correct Q factor. If we use Q factors that are too far away from the Q factor of the observed data the inversion result becomes worse

A dopaminergic mechanism of antipsychotic drug efficacy, failure, and failure reversal: the role of the dopamine transporter

Antipsychotic drugs are effective interventions in schizophrenia. However, the efficacy of these agents often decreases over time, which leads to treatment failure and symptom recurrence. We report that antipsychotic efficacy in rat models declines in concert with extracellular striatal dopamine levels rather than insufficient dopamine D2 receptor occupancy. Antipsychotic efficacy was associated with a suppression of dopamine transporter activity, which was reversed during failure. Antipsychotic failure coincided with reduced dopamine neuron firing, which was not observed during antipsychotic efficacy. Synaptic field responses in dopamine target areas declined during antipsychotic efficacy and showed potentiation during failure. Antipsychotics blocked synaptic vesicle release during efficacy but enhanced this release during failure. We found that the pharmacological inhibition of the dopamine transporter rescued antipsychotic drug treatment outcomes, supporting the hypothesis that the dopamine transporter is a main target of antipsychotic drugs and predicting that dopamine transporter blockers may be an adjunct treatment to reverse antipsychotic treatment failure

Sculpture Projects in Münster 1997

This catalogue documents a major exhibition of contemporary sculpture held every ten years in Münster. Grasskamp's analysis of art and the city focuses on sculptural interventions in public space. Works by Oldenburg, Beuys, Asher, Serra, Judd and Haacke are discussed in relation to narrative space, architectural facade, performance, politics and site-specificity. Daniel Buren focuses on the differences between art in the museum and out in the street. Artist's statements. 85 bibl. ref