Fractal basins of escape and the formation of spiral arms in a galactic potential with a bar

We investigate the dynamics in the close vicinity of and within the critical area in a 2D effective galactic potential with a bar of Zotos. We have calculated Poincar\'e surfaces of section and the basins of escape. In both the Poincar\'e surfaces of section and the basins of escape we find numerical evidence for the existence of a separatrix which hinders orbits from escaping out of the bar region. We present numerical evidence for the similarity between spiral arms of barred spiral galaxies and tidal tails of star clusters.Comment: 12 pages, 10 figures, accepted by MNRA

Cooperativeness and Impatience in the Tragedy of the Commons

This paper examines the role of other-regarding and time preferences for cooperation in the field. We study the preferences of fishermen whose main, and often only, source of income stems from using a common pool resource (CPR). The exploitation of a CPR involves a negative interpersonal and inter-temporal externality because individuals who exploit the CPR reduce the current and the future yield for both others and themselves. Accordingly, economic theory predicts that more cooperative and more patient individuals should be less likely to exploit the CPR. Our data supports this prediction because fishermen who exhibit a higher propensity for cooperation in a laboratory public goods experiment, and those who show more patience in a laboratory time preference experiment, exploit the fishing grounds less in their daily lives. Moreover, because the laboratory public goods game exhibits no inter-temporal spillovers, measured time preferences should not predict cooperative behavior in the laboratory. This prediction is also borne out by our data. Thus, laboratory preference measures are useful to capture important dimensions of field behavior.cooperation, common pool resource, experiments, generalizability, methodology

Promoting Islamic Finance and Islamic Banking: a legal analysis of the potential for Islamic Banking products in Germany

In recent years, Islamic banking has been one of the fastest growing markets in the financial world. Even to German banks, Islamic finance is not as 'foreign' as one might think. Indeed, several banks are already operating so-called "Islamic windows" in various Arab countries. However, German banks are still reluctant to offer 'Islamic' products in Germany, despite the fact that approximately 3.5 million Muslims currently live there. Potential reasons for this reluctance include widespread misunderstanding of Islamic banking in Germany and prevailing cultural prejudice towards Islam generally. The author seeks to address these concerns and to take an objective approach towards understanding the potential for Islamic banking in Germany. Legally, Islamic law cannot be the governing law of any contract in Germany. Therefore, the aim must be to draft contracts that are both enforceable under German law and consistent with the principles of Shari'a - the Islamic law. In this paper, the author gives a detailed legal analysis of the most common Islamic banking products and how they could be given effect under German law, while attempting to address widespread concerns about arbitration or parallel Shari'a courts. This publication is one of the first legal analysis of Islamic banking products in Germany. As such, its goal is not to be the final word, but rather to begin the conversation about potential problems and conflicts of Islamic banking in Germany that require further investigation

Transmission Expansion Planning Considering Energy Storage

In electricity transmission networks, energy storage systems (ESS) provide a means of upgrade deferral by smoothing supply and matching demand. We develop a mixed integer programming (MIP) extension to the transmission network expansion planning (TEP) problem that considers the installation and operation of ESS as well as additional circuits. The model is demonstrated on the well known Garver's 6-bus and IEEE 25-bus test circuits for two 24 hour operating scenarios; a short peak, and a long peak. We show optimal location and capacity of storage is sensitive not only to cost, but also variability of demand in the network

miR-200c sensitizes breast cancer cells to doxorubicin treatment by decreasing TrkB and Bmi1 expression.

Acquired resistance to classical chemotherapeutics is a major obstacle in cancer treatment. Doxorubicin is frequently used in breast cancer therapy either as single-agent or in combination with other drugs like docetaxel and cyclophosphamide. All these chemotherapies have in common that they are administered sequentially and often result in chemoresistance. Here, we mimicked this pulse therapy of breast cancer patients in an in vitro cell culture model, where the epithelial breast cancer cell line BT474 was sequentially treated with doxorubicin for several treatment cycles. In consequence, we obtained chemoresistant cells displaying a mesenchymal-like phenotype with decreased levels of miR-200c. To investigate the involvement of miR-200c in resistance formation, we inhibited and overexpressed miR-200c in different cell lines. Thereby, the cells were rendered more resistant or susceptible to doxorubicin treatment. Moreover, the receptor tyrosine kinase TrkB and the transcriptional repressor Bmi1 were identified as miR-200c targets mediating the drug resistance. Hence, we provide a mechanism of acquired resistance to doxorubicin that is caused by the loss of miR-200c. Along with this, our study demonstrates the complex network of microRNA mediated chemoresistance highlighting the challenges in cancer therapy and the importance of novel microRNA-modulating anticancer agents

Continuous Simulation for Urban Energy Planning Based on a Non-Linear Data-Driven Modelling Approach

The thesis develops the argument for scale sensitive local energy planning, combining energy demand simulation with the development of continuous benchmarks. A non-linear data driven modelling approach is selected to represent space heating needs for urban areas. The model is applied to the scale of buildings, building clusters and neighbourhoods and compared to measured data in order to test its scalability. The results confirm the applicability of the approach to the scale of neighbourhoods