Comparison of three modelling approaches of potential natural forest habitats in Bavaria, Germany

In the context of the EU Habitats Directive, which contains the obligation of environmental monitoring, nature conservation authorities face a growing demand for effective and competitive methods to survey protected habitats. Therefore the presented research study compared three modelling approaches (rule-based method with applied Bavarian woodland types, multivariate technique of cluster analysis, and a fuzzy logic approach) for the purpose of detecting potential habitat types. The results can be combined with earth observation data of different geometric resolution (ASTER, SPOT5, aerial photographs or very high resolution satellite data) in order to determine actual forest habitat types. This was carried out at two test sites, situated in the pre-alpine area in Bavaria (southern Germany). The results were subsequently compared to the terrestrial mapped habitat areas of the NATURA 2000 management plans. First results show that these techniques are a valuable support in mapping and monitoring NATURA 2000 forest habitats

The genetics of experimental arthritis in rodents

Unravelling the genetic susceptibility to complex autoimmune diseases and understanding these pathologies on a mechanistic level are major obstacles to improve our possibilities for therapeutic intervention and an increase in the quality of life of affected patients. Studies in experimental rodent models, that can be run under stable environmental conditions, which itself can be subjected to experimental manipulation, and in cohorts of potentially unlimited size, hold significant promise for the understanding of genes and pathways involved in complex autoimmune diseases. In this thesis, which is based on five scientific manuscripts, we initially investigated the influence of the genetic background on the ability to detect three major genetic loci (Pia4/Cia12, Pia5/Cia3, Pia7/Cia13) for pristane induced arthritis (PIA) in the rat. We also investigated the effect of Pia1, which includes the RT1 region (major histocompatibility complex (MHC) in the rat). We could show that the major arthritis regulator NCF1 as well as the MHC are silent in certain genetic backgrounds, whereas their genetic effect on PIA susceptibility can be detected in other, distinct genetic setups, arguing for the importance of genetic interactions between MHC and non-MHC genes for PIA development. In the second and third paper, we used a unique approach with a heterogeneous stock (HS) derived inbred-outbred mouse cohort that had been backcrossed to the arthritis susceptible C57BL10/Q (BQ) mouse strain, in order to map clinical phenotypes and the autoantibody response during collagen induced arthritis (CIA) development. We defined numerous novel loci and fine mapped already described quantitative trait loci (QTL) associated with clinical disease and/or autoantibody production providing the to date most comprehensive mapping study in CIA. The papers 4 and 5 concern the positional identification of candidate genes for the CIA loci Cia21 and Cia22 in the mouse. We propose the costimulatory molecule CD2 as a female specific genetic risk factor for autommunity in the joint and the central nervous system (CNS). We also pinpoint the chitinase like gene Chi3l3, also denoted as Ym1, as an important immunomodulator in experimental murine arthritis models based on both active immunization with collagen (CII) and passive transfer of arthritogenic antibodies. Hopefully, the findings presented in this thesis will have clinical implications based on the novel genetic targets, we identified. In addition, our data demonstrate the difficulties and pitfalls that are associated with gene identification using a hypothesis free positional cloning approach in experimental rodent populations

Una descripción inédita de Guayaquil

4 p.La gran descripción de Guayaquil, la mejor de todas, es la que en 1774 hizo el ingeniero don Francisco Requena, a quien se deben también un plano del puerto, un mapa de toda la provincia y numerosos informes sobre su situación defensiva, sanitaria, etc. (obra publicada por Mª Luisa Laviana en Historiografía y Bibliografía Americanistas, XXVI, 1982, y reeditada como libro por la Escuela de Estudios Hispano-Americanos en 1984). Pero ahora damos a conocer una pequeña descripción que con el título de “Relación de Guayaquil y plano de la ciudad” se encuentra en el Servicio Histórico Militar de Madrid. Tiene el indudable valor de proporcionar una rápida y pintoresca visión del Guayaquil de la década de 1770, a la vez que su misma brevedad facilita su publicación.Peer reviewe

A tip-based source of femtosecond electron pulses at 30keV

We present a nano-scale photoelectron source, optimized towards ultrashort pulse durations and well-suited for time-resolved diffraction experiments. A tungsten tip, mounted in a suppressor-extractor electrode configuration, allows the generation of 30 keV electron pulses with an estimated pulse duration of 37 fs at the gun exit. We infer the pulse duration from particle tracking simulations, which are in excellent agreement with experimental measurements of the electron-optical properties of the source. We furthermore demonstrate femtosecond laser-triggered operation. Besides the short electron pulse duration, a tip-based source is expected to feature a large transverse coherence as well as a nanometric emittance.Comment: 4 pages, 3 figure

Towards an experimentally feasible controlled-phase gate on two blockaded Rydberg atoms

We investigate the implementation of a controlled-Z gate on a pair of Rydberg atoms in spatially separated dipole traps where the joint excitation of both atoms into the Rydberg level is strongly suppressed (the Rydberg blockade). We follow the adiabatic gate scheme of Jaksch et al. [1], where the pair of atoms are coherently excited using lasers, and apply it to the experimental setup outlined in Ga\"etan et al. [2]. We apply optimisation to the experimental parameters to improve gate fidelity, and consider the impact of several experimental constraints on the gate success.Comment: 10 pages, 14 figure