Alpine glaciers are valuable archives for the reconstruction of human impact on the environment. Besides dating purposes, measurement of radiocarbon (14C) content provides a powerful tool for long-term source apportionment studies on the carbonaceous aerosols incorporated in ice cores. In this work, we present an extraction system for 14C analyses of dissolved organic carbon (DOC) in ice cores. The setup can process ice samples of up to 350 g mass and offers ultra-clean working conditions for all extraction steps. A photo-oxidation method is applied by means of external UV irradiation of the sample. For an irradiation time of 30 min with catalyzation by addition of Fe2+ and H2O2, we achieve an efficiency of 96 ± 6% on average. Inert gas working conditions and stringent decontamination procedures enable a low overall blank of 1.9 ± 1.6 μg C with a F14C value of 0.68 ± 0.13. This makes it possible to analyze the DOC in ice samples with a carbon content of as low as 25 μg C kg−1 ice. For a first validation, the new method was applied to ice core samples from the Swiss Alps. The average DOC concentration and F14C values for the Fiescherhorn ice core samples show good agreement with previously reported data for the investigated period of 1925–1936 AD.

The enrichment of the Intra-Cluster Medium (ICM) with heavy elements is reviewed. There is now good observational evidence for enrichment including abundance ratios and metallicity distributions. Various processes involved in the enrichment process – ram-pressure stripping, galactic winds, galaxy-galaxy interactions, AGN outflows and intra-cluster supernovae – are described. Simulations of the ICM evolution taking into account metal enrichment are presented.

We present an investigation of the metal enrichment of the intra-cluster medium (ICM) by galactic winds and merger-driven starbursts. We use combined N-body/hydrodynamic simulations with a semi-numerical galaxy formation model. The inhomogeneities in the metal distribution caused by these processes are an ideal tool to reveal the dynamical state of a galaxy cluster. We show that X-ray weighted metal maps distinguish between pre- or post-merger galaxy clusters by comparing the metallicity distribution with the galaxy-density distribution: pre-mergers have a metallicity gap between the subclusters, post-mergers a high metallicity between subclusters.

We investigate the morphologies and velocity fields of spiral galaxies in distant clusters (z ~ 0.5) focussing on signatures from interactions. Structural parameters and peculiarities are determined with HST/ACS images. To derive the internal kinematics and rotation curves we have performed 3D–spectroscopy allowing the construction of the full velocity field for each galaxy. Combining both approaches, transformation mechanisms are revealed that affect not only the stellar populations but also the mass distribution. The observations are supported by N-body/SPH simulations of different interaction processes.

We present a systematic investigation of the velocity fields of both isolated and interacting spiral galaxies in combined N-body/hydrodynamical simulations. Closely mimicking the procedures applied in observations of distant, small, and faint galaxies we extract rotation curves (RCs) and compare the results of the simulation directly to observations. Irregularities in the velocity field reflect disturbances in the gravitational potential of the galaxy. They can be used to trace the recent interaction history of a galaxy and give possible clues to the type of the respective interaction. In addition, identifying disturbances in the RCs is important for Tully-Fisher studies in order to accurately derive the maximum rotation velocity.

We present XMM-Newton observations of the galaxy cluster Abell 514. This cluster shows a very complex X-ray morphology. Radio observations show that there are six radio sources located inside the cluster. This makes it possible to determine the magnetic field strength using the Faraday rotation method. This cluster is an example for the hierarchical growth of structure and a very interesting object for studying the correlation between magnetic field strength and X-ray properties.

We present the preliminary results from a combined X-ray/ lensing investigation of the galaxy cluster RBS 864 (z = 0.29). Morphological and spectral studies of X-ray data show a relaxed appearance of this cluster, thus allowing us to derive a good mass estimate. From optical data we found the presence of a very high number of arc candidates and performed a strong lensing mass analysis. We found a large discrepancy in the comparison of the X-ray and lensing masses.

Colonial metazoans that lived symbiotically with hermit-crabs create striking and distinctive fossils. Examples of such fossils recorded (Schindler and Portell, 1993) from Cenozoic deposits in Florida include the scleractinian coral Septastrea marylandica (Conrad, 1841) (see Darrell and Taylor, 1989), the hydrozoan Cystactinia ocalana Brooks, 1964, and the bryozoan Hippoporidra edax (Busk, 1859) [recorded as H. calcarea (Smitt) by Scolaro, 1970]. In all of these fossils, the symbiotic colony covers the entire external surface of a gastropod shell with a thick encrustation. Growth of the colony outwards from the shell aperture in the form of a helicospiral tube greatly extends the size of the chamber available for the hermit-crab occupant. In no known fossil examples of symbioses are the hermit-crabs preserved in situ. However, modern analogues, along with functional morphological considerations, provide good criteria for inferring that this peculiar colonial growth pattern occurred in response to the presence of a symbiotic hermit-crab, at least for examples within the Lower Jurassic-Recent range known for fossil hermit-crabs (see Walker, 1992; Taylor, 1994).

Sub-lithographic copper damascene lines were fabricated to investigate already today the physical phenomena and scaling limits of metallic conductors in the metallization systems of chip generations which are believed to be in production 10 years from now and later. Using standard manufacturing processes and state-of-the-art process tools, including standard lithography tools, narrow copper lines were fabricated at the expense of a relaxed pitch by use of a removable spacer technique. These copper nano interconnects were passivated and subjected to electrical measurements. Our results show that continuous down scaling to increase device performance will result in an unfavorable increase of the electrical resistivity of copper in stateof-the-art metallization schemes. Electrical measurements over a wide range of temperatures down to cryogenic temperatures reveal the limited potential of cooling to reduce resistivity of conductors as lateral dimensions will be shrinked down to the sub-100nm regime. By down scaling of copper diffusion barriers in damascene trenches, barrier functionality was demonstrated after high temperature anneals and excessive bias-temperature stress tests for films meeting or even exceeding end-of-roadmap thickness requirements. An analysis of the temperature dependence of the leakage current measured at very high electric fields applied between neighboring damascene lines suggests the conduction mechanism in the SiO2 used as intermetal dielectric to be Frenkel-Poole type rather than Schottky emission. Electromigration life times of sub-100nm copper lines embedded in oxide were found to be comparable with those obtained for similar structures fabricated with today's feature sizes.

Scanning Probe Recognition Microscopy is a new scanning probe capability under development within our group to reliably return to and directly interact with a specific nanoscale feature of interest, without the use of a zoom box with its thermal drift and local origin difficulties. It is a recognition-driven and learning approach, made possible through combining SPM piezoelectric implementation with on-line image processing and dynamically adaptive learning algorithms. Segmentation plus a recognized pattern is implemented within a scan plan and used to guide the tip in a recognition-driven return to a specific site.

The specific application focus of our group is on the development of Scanning Probe Recognition Microscopy for nanobiological investigations. In the present work, Scanning Probe Recognition Microscopy is used in a direct investigation of the surface and elastic properties along individual tubules within a tissue scaffolding matrix. Elastic properties are indicated as important influences on actin polymerization and consequent cell pseudopodia extension and contraction.