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International audience; Combining quasistatic and time-resolved transport measurements with X-ray and neutron diffrac-tion experiments we study the non-equilibrium states that arise in pure and in Ti substituted Ca2RuO4 under the application of current densities. Time-resolved studies of the current-induced switching find a slow conductance relaxation that can be identified with heating and a fast one that unambiguously proves an intrinsic mechanism. The current-induced phase transition leads to complex diffraction patterns. Separated Bragg reflections that can be associated with the metallic and insulating phases by their lattice parameters, indicate a real structure with phase coexistence that strongly varies with temperature and current strength. A third contribution with a c lattice constant in between those of metallic and insulating phases appears upon cooling. At low current densities, this additional phase appears below ∼100 K and is accompanied by a suppression of the antiferromagnetic order that otherwise can coexist with current carrying states. A possible origin of the intermediate phase is discussed.

Private Public Partnerships (PPP) are getting established in an increasing rate. They are seen as perfect substitutes to traditional procurement of public goods and services, like education, health care or infrastructure. Their objective is to deliver the public goods / services to the public in higher efficiency, higher quality and contribute to the country’s economic growth. This thesis analyses modern PPPs and why some of them tend to fail in the long run. For this thesis, failure means the PPP becomes a public company, has high transaction costs or gained a bad reputation during its operation period, because the public has to carry the main costs of the potential malfunction. To reach the thesis objective, the thesis is split in two main parts: the theoretical approach and the case study. The theoretical approach evaluates of PPPs on the theoretical level, the case study gives a real-life example for a PPP, the “Toll Collect GmbH” from Germany. During the research for both approaches, several factors and issues emerged considering the PPP-performance. These findings are the main focus in the discussion and are vital for the overall PPP-success. The research findings indicate that human misbehaviour (opportunism, etc.), internal problems between the partners (conflict of interest), the bias reliability of the available “hard data” and planning mistakes on microeconomic level are responsible for a PPP-failure. These findings are related to other issues regarding transparency, monitoring and cost handling of PPPs. To reduce the failure rate for the future, the thesis proposes a better governance structure with an independent audit body, CSR standards for the project partners and the higher consideration of scientific research in that field during the planning period.

Near-field holography (NFH) combined with electron beam lithography (EBL)-written phase masks is a promising method for the rapid realization of diffraction gratings with high resolution and high accuracy in line density distribution. We demonstrate a dynamic exposure method in which the grating substrate is shifted during pattern transfer. This reduces the effects of stitching errors, resulting in the decreased intensity of the optical stray light (i.e., Rowland ghosts). We demonstrate the intensity suppression of ghosts by 60%. This illustrates the potential for dynamic NFH to suppress undesirable periodic patterns from phase masks and alleviate the stitching errors induced by EBL.

One of the most ambitious endeavors in the field of diabetes technology is non-invasive glucose sensing. In the past decades, a number of different technologies have been assessed, but none of these have found its entry into general clinical use. We report on the development of a table-top confocal Raman spectrometer that was used in the home of patients with diabetes and operated for extended periods of time unsupervised and without recalibration. The system is based on measurement of glucose levels at a ‘critical depth’ in the skin, specifically in the interstitial fluid located below the stratum corneum but above the underlying adipose tissue layer. The region chosen for routine glucose measurements was the base of the thumb (the thenar). In a small clinical study, 35 patients with diabetes analyzed their interstitial fluid glucose for a period of 60 days using the new critical-depth Raman (CD-Raman) method and levels were correlated to reference capillary blood glucose values using a standard finger-stick and test strip product. The calibration of the CD-Raman system was stable for > 10 days. Measurement performance for glucose levels present at, or below, a depth of ~250μm below the skin surface was comparable to that reported for currently available invasive continuous glucose monitors. In summary, using the CD-Raman technology we have demonstrated the first successful use of a non-invasive glucose monitor in the home.

Grundsatzlich kann das Immunsystem Tumorzellen erkennen und eliminieren. Trotzdem gelingt es Tumorzellen, der Immunuberwachung zu entgehen. Grundgedanke der Immuntherapie ist es, das korpereigene Abwehrsystem so zu aktivieren, dass es maligne Zellen wieder erkennt und beseitigt. In den letzten Jahren wurden vielfaltige immunonkologische Therapiestrategien entwickelt, z. B. bi- und multispezifische oder immunregulatorische Antikorper, genmodifizierte T-Lymphozyten oder Tumorvakzinen. Einige Therapeutika sind bereits zugelassen, andere in klinischen Studien zuganglich. Dieser Beitrag stellt die aktuell aussichtsreichen Ansatze der Immunonkologie und deren immunbiologische Grundlagen vor. Derzeit besteht noch erheblicher Forschungsbedarf – so mussen Biomarker fur zielgerichtete Therapiestrategien etabliert und die Langzeitwirkung sowie Kombinierbarkeit von Therapien untersucht werden. Dennoch wird die Immunonkologie in wenigen Jahren fester Bestandteil onkologischer Behandlungskonzepte sein.

The PENTATRAP-experiment in Heidelberg for high precision mass measurements is using a construction of 5 Penning traps and focuses on long-living heavy ions. This bachelor thesis is about the distribution of radiofrequency excitations to create a quadrupole field within a Penning trap. For this a module of a multiplexer box was developed and tested on suitability. This possibility of distributing should give more exibility with the excitation and also a saving of time between different measurements. The quadrupole excitation with radiofrequencies was simulated to obtain the optimized potentials of the trap electrodes. Those should be useful in the first startup of the experiment and can serve as a rough starting point.

In this study, we investigate analytically and experimentally the roles of quasi-linearly polarized (LP), hybrid, plasmonic and photonic modes in optical detection and excitation with aperture tips in scanning near-field optical microscopy. Aperture tips are tapered and metal-coated optical fibers where small circular apertures are made at the apex. In aperture tips, there exist plasmonic modes that are bound at the interface of the metal cladding to the inner dielectric fiber and photonic modes that are guided in the area of the increased index in the dielectric fiber core. The fundamental photonic mode, although excited by the free-space Gaussian beam, experiences cutoff and turns into an evanescent mode. The photonic mode also becomes lossier than the plasmonic mode toward the tip aperture, and its power decay due to absorption and reflection is expected to be at least 10 -9 . In contrast, the fundamental plasmonic mode has no cutoff and thus reaches all the way to the tip aperture. Due to the non-adiabaticity of both modes' propagations through the taper below a core radius of 600 nm, there occurs coupling between the modes. The transmission efficiency of the plasmonic mode, including the coupling efficiency and the propagation loss, is expected to be about 10 -6 that is at least 3 orders of magnitude larger than that of the photonic mode. Toward the tip aperture, the longitudinal field of the photonic mode becomes stronger than the transverse ones while the transverse fields always dominate for the plasmonic mode. Experimentally, we obtain polarization resolved images of the near-field at the tip aperture and compare with the x- and y-components of the fundamental quasi-LP plasmonic and photonic modes. The results show that not only the pattern but also the intensity ratios of the x- and y-components of the aperture near-field match with that of the fundamental plasmonic mode. Consequently, we conclude that only the plasmonic mode reaches the tip aperture and thus governs the near-field interaction outside the tip aperture. Our conclusion remains valid for all aperture tips regardless of the cladding metal type that mainly influences the total transmission efficiency of the aperture tip.

This paper explores the hypothesis that international capital flows are driven in part by the level of economic activity. It investigates the existence of the income mobility of capital, as distinct from the interest mobility of capital, by using Hsiao's approach to testing for Granger causality to model the relationship between Australian investment abroad and the Australian real GDP. We find some evidence that income causes capital flows but no evidence to support reverse causation from capital flows to income. This result suggests that the analytical construct of the income mobility of capital has empirical content.