Angiogenese - therapeutische Interventionsmöglichkeiten bei rheumatischen Erkrankungen

Zusammenfassung: Im Gegensatz zur Vaskulogenese bedeutet Angiogenese die Formation neuer Blutgefäße aus bereits bestehenden Gefäßen. Dieser vielschrittige Prozess tritt beim Erwachsenen physiologisch nur während des Reproduktionszyklus und der Schwangerschaft auf, pathophysiologisch bei Wundheilung und Entzündung, aber auch bei Tumorwachstum und Metastasierung. Zugrunde liegende Mechanismen sind Vasodilatation und Steigerung der Gefäßpermeabilität, gefolgt von einer Destabilisierung der Gefäßwände und der extrazellulären Matrix mit anschließender Endothelzellproliferation und -migration, die zur Bildung eines neuen Gefäßsystems führt, das schließlich durch Perizyten und glatte Muskelzellen stabilisiert wird. Dieser Ablauf wird durch ein komplexes Zusammenspiel proangiogener und angiostatischer Faktoren kontrolliert. Im Gegensatz zur Karzinogenese ist die Bedeutung der Angiogenese für die Pathogenese und Therapie rheumatischer Erkrankungen bisher weniger gut untersucht. In diesem Übersichtsartikel werden verschiedene Aspekte pathologischer Angiogenese im Hinblick auf therapeutische Optionen bei der rheumatoiden Arthritis (RA) und der systemischen Sklerose (SSc) diskutier

Die Entwicklung regionaler Netzwerke Sozialer Landwirtschaft in Bayern

This paper deals with the establishment and advancement of Social Farming networks in Bavaria. The scientific research of the thesis is based on literature research, the participation in network meetings and as a main point 14 guideline-based interviews. First of all the main motivations and aims of network participants will be described. Thereafter past, present and possible future steps of the three networks in Bavaria will be presented. The final discussion provides assistance, also to other networks, by presenting key success factors of the Bavarian networking activities

World-sheet Stability of (0,2) Linear Sigma Models

We argue that two-dimensional (0,2) gauged linear sigma models are not destabilized by instanton generated world-sheet superpotentials. We construct several examples where we show this to be true. The general proof is based on the Konishi anomaly for (0,2) theories.Comment: 18 pages, LaTe

Field condensations and Noncritical String for c>1

Quantum theory of 2d gravity for $c>1$ is examined as a non-critical string theory by taking account of the loop-correction of open strings whose end points are on the 2d world surface of the closed string. This loop-correction leads to a conformal anomaly, and we obtain a modified target-space action which implies a new phase of the non-critical closed-string. In this phase, the dual field of the gauge field, which lives on the boundary, condenses and the theory can be extended to $c>1$ without any instability.Comment: 17 pages, Latex, no figur

An Exact Solution to O(26) Sigma Model coupled to 2-D Gravity

By a mapping to the bosonic string theory, we present an exact solution to the O(26) sigma model coupled to 2-D quantum gravity. In particular, we obtain the exact gravitational dressing to the various matter operators classified by the irreducible representations of O(26). We also derive the exact form of the gravitationally modified beta function for the original coupling constant $e^2$. The relation between our exact solution and the asymptotic solution given in ref[3] is discussed in various aspects.Comment: 10 pages, pupt-144

On the validity of ADM formulation in 2D quantum gravity

We investigate 2d gravity quantized in the ADM formulation, where only the loop length $l(z)$ is retained as a dynamical variable of the gravitation, in order to get an intuitive physical insight of the theory. The effective action of $l(z)$ is calculated by adding scalar fields of conformal coupling, and the problems of the critical dimension and the time development of $l$ are addressed.Comment: 12 page

Patterns of quark mass matrices in a class of Calabi-Yau models

We study a class of superstring models compactified in the 3-generation Calabi-Yau manifold of Tian and Yau. Our analysis includes the complete $E_6$-singlet sector, which has been recently evaluated using techniques of spectral and exact sequences. We use the discrete symmetries of the models to find flat directions of symmetry breaking that leave unbroken a low energy matter parity and make all leptoquarks heavy while preserving light Higgs fields. Then we classify the patterns of ordinary quark mass matrices and show that (without invoking effects due to nonrenormalizable terms) only one structure can accommodate the observed value of fermion masses and mixing angles, with preference for a heavy {\it top} quark ( $m_t\ge 170$ GeV for $V_{13}\le 0.013$ ). The model, which unifies perturbatively and predicts a realistic structure of quark mass matrices with texture zeroes, is one of the many possible string vacua. However, in contrast with what is often assumed in the search for realistic unified scenarios, it is highly nonminimal near the unification scale and the predicted mass matrices have no simple symmetry properties.Comment: 30 (including Tables and Figures), UG-FT-38/9

Fermionic characters for graded parafermions

Fermionic-type character formulae are presented for charged irreduciblemodules of the graded parafermionic conformal field theory associated to the coset $osp(1,2)_k/u(1)$. This is obtained by counting the weakly ordered `partitions' subject to the graded $Z_k$ exclusion principle. The bosonic form of the characters is also presented.Comment: 24 p. This corrects typos (present even in the published version) in eqs (4.4), (5.23), (5.24) and (C.4

Continuum Annulus Amplitude from the Two-Matrix Model

An explicit expression for continuum annulus amplitudes having boundary lengths $\ell_{1}$ and $\ell_{2}$ is obtained from the two-matrix model for the case of the unitary series; $(p,q) = (m + 1, m)$. In the limit of vanishing cosmological constant, we find an integral representation of these amplitudes which is reproduced, for the cases of the $m = 2~(c=0)$ and the $m \rightarrow \infty~(c=1)$, by a continuum approach consisting of quantum mechanics of loops and a matter system integrated over the modular parameter of the annulus. We comment on a possible relation to the unconventional branch of the Liouville gravity.Comment: 9 pages, OU-HET 190, revised version. A part of the conclusions has been corrected. A new result on integral representation of the annulus amplitudes has been adde