The Executive Turnover Risk Premium

We establish that CEOs of companies experiencing volatile industry conditions are more likely tobe dismissed. At the same time, industry risk is, controlling for various other factors, unlikelyto be directly associated with CEO compensation other than through dismissal risk. Using thisidentification strategy, we document that CEO turnover risk is significantly positively associatedwith compensation. This finding is important because job-risk compensating wage differentials arisenaturally in competitive labor markets. By contrast, the evidence rejects a simple entrenchmentmodel according to which powerful CEOs have lower job risk and at the same time secure highercompensation

Action at a Distance

The mediality of transmission and the materiality of communication result today more than ever in "acting at a distance" - an action whose agency lies in a medium. This book provides an overview into this crucial phenomenon, thereby introducing urgent questions of human interaction, the binding and breaking of time and space, and the entanglement of the material and the immaterial. Three vivid inquiries deal with histories and theories of mediality and materiality

Pathologie-assoziierte Expression und Funktion der Metalloproteasen Meprin α und Meprin β

By proteolysis, the enzymatic cleavage of peptide bonds, proteins undergo an irreversible posttranslational modification which is used for protein maturation, signaling and cellular adhesion. The work of this thesis approaches the role of the extracellular metalloproteases meprin α and meprin β in physiological and pathological conditions, especially in skin and inflammation related diseases. The first part of this thesis addresses the meprin expression in murine skin and their resulting role in wound healing and deposition of extracellular matrix in this organ. Based on previous findings that meprins are over-expressed in fibrotic and hyperkeratotic skin diseases, we analyzed mouse models over-expressing meprin β in skin in order to study its contribution to the onset of disease. Fra2 transgenic mice develop skin fibrosis and over-express meprin β in skin. Since Fra2 activates several other genes besides the meprin β gene, mouse models directly over-expressing meprin β in skin were generated. Epidermal over-expression of meprin β led to a pigmentary phenotype and hyperproliferation of keratinocytes. On the other hand, a dermal over-expression of meprin β did not show an obvious phenotype or development of fibrosis. The second part focused on proteolytic processing of the adhesion molecule CD99. Cleavage of CD99 by meprin β had an effect on transendothelial migration of cancer cells and inhibition of meprin β delayed infiltration of immune cells in an acute inflammation model. Finally, altered localization of meprin α was investigated during pathological conditions. Under normal conditions, soluble meprin α was observed to bind to epithelial cells via heparan sulphate, which had impact on infiltration of immune cells and epithelial barrier integrity. Moreover, covalent binding of meprin α to meprin β on the secretory pathway could also tether soluble meprin α to the plasma membrane. The altered localization of meprin α contributed to inflammatory disease progression

Preparation of a porphyrinic bis(pyridyl aldehyde) and its supramolecular complexes

Shape-specific molecular assemblies require the preparation of the constituent building blocks with the necessary properties to bias exclusive formation of the proposed structures. In this work, a novel linear porphyrin dialdehyde was synthesised and used to assemble a supramolecular grid via Cu(I) heteroleptic phenanthroline/pyridyl imine complexation, and a tetrahedral cage via Fe(II) pyridyl imine coordination.We gratefully acknowledge funding from the Consejo Nacional de Ciencia y Tecnologia (CONACYT) Mexico (MAAG) and the Cambridge NanoDTC (CRG).This is the author accepted manuscript. The final version is available from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C5CC06399

Tracking Control for a Spherical Pendulum via Curriculum Reinforcement Learning

Reinforcement Learning (RL) allows learning non-trivial robot control laws purely from data. However, many successful applications of RL have relied on ad-hoc regularizations, such as hand-crafted curricula, to regularize the learning performance. In this paper, we pair a recent algorithm for automatically building curricula with RL on massively parallelized simulations to learn a tracking controller for a spherical pendulum on a robotic arm via RL. Through an improved optimization scheme that better respects the non-Euclidean task structure, we allow the method to reliably generate curricula of trajectories to be tracked, resulting in faster and more robust learning compared to an RL baseline that does not exploit this form of structured learning. The learned policy matches the performance of an optimal control baseline on the real system, demonstrating the potential of curriculum RL to jointly learn state estimation and control for non-linear tracking tasks