On the Hedging of Options On Exploding Exchange Rates

We study a novel pricing operator for complete, local martingale models. The new pricing operator guarantees put-call parity to hold for model prices and the value of a forward contract to match the buy-and-hold strategy, even if the underlying follows strict local martingale dynamics. More precisely, we discuss a change of num\'eraire (change of currency) technique when the underlying is only a local martingale modelling for example an exchange rate. The new pricing operator assigns prices to contingent claims according to the minimal cost for superreplication strategies that succeed with probability one for both currencies as num\'eraire. Within this context, we interpret the lack of the martingale property of an exchange-rate as a reflection of the possibility that the num\'eraire currency may devalue completely against the asset currency (hyperinflation).Comment: Major revision. Accepted by Finance and Stochastics. The original publication is available at http://link.springer.co

Dams and ramparts, cattle and goats: symbolic capital and the Central Mauretanian slaves and haratin struggle for emancipation and autonomy

Die 1995/96 durchgeführte Fallstudie untersucht die Konfigurationen von Hierarchie und Abhängigkeiten im ländlichen Mauretanien wie sie in den vergangenen Jahrzehnten durch den Übergang von der Sklaverei zur "freien" lohnabhängigen Arbeit entstanden sind. Im Zuge dieser Transformation ist eine Form der Herrschaft entstanden, die eine spezifische Konstellation von Sklaven, befreiten Sklaven und ihren ehemaligen Herren umfaßt. Der Autor vergleicht diese Interdependenzen mit den Figuren und Abläufen eines Tanzes, in dem jede Bewegung und Veränderung in einem Gesamtensemble synchronisiert ist. Mit jeder Reallokation in diesem Ensemble wird auch das symbolische Kapital (Status, Prestige) der Spieler neu definiert und verteilt. Autonomie, Freiheit und Emanzipation sind in diesem "Spiel" daher eine streng relative Größe. (pre

Lernen auf eigenen Wegen - mit Kernideen und Reisetagebüchern

Im September 1990 ist das Buch "Sprache und Mathematik in der Schule. Auf eigenen Wegen zur Fachkompetenz" (LCH / Lehrmittelverlag Zürich) erschienen, in welchem Untersuchungen der beiden Autoren zum individuellen Lernverhalten und die daraus abgeleitete Didaktik der Kernideen und des Reisetagebuchs dargestellt sind. Es wird nachgewiesen und an Beispielen erläutert, dass eine grundlegend neue Einstellung gegenüber den Schulstoffen und den Schülerprodukten Voraussetzung ist für einen Unterricht, in welchem der Aufbau einer fundierten Fachkompetenz und die Bildung einer selbständigen und verantwortungsbewussten Persönlichkeit sich wechselseitig fördern und bedingen. Das Konzept "Lernen auf eigenen Wegen" ist in den Jahren 1988 bis 1990 als Schulprojekt der Erziehungsdirektion Zürich mit sieben Klassen auf allen Stufen der Volksschule erprobt worden. Ein kurzer Einblick in dieses Projekt soll hier zeigen, wie die Arbeit mit Kernideen und Reisetagebüchern in der Praxis aussieht und auf welchen didaktischen Prinzipien sie beruht. Daraus ergeben sich auch Konsequenzen für die Aus- und Fortbildung der Lehrerinnen und Lehrer

Ending Slavery

»Ending Slavery« offers insights into the »how« of practices of slavery that persist in parts of Mauritania up to the present day. It brings to the light the gendered structures of Moorish slavery, and examines their impact on strategies and tactics designed to bring this institution to an end. Underlying this study is empirical data gathered during two periods of field research in rural central Mauritania. The analysis of life histories of slaves and freed slaves, but also of tributaries and free Moors plays a key role in the book

Near-term quantum-repeater experiments with nitrogen-vacancy centers: Overcoming the limitations of direct transmission

Quantum channels enable the implementation of communication tasks inaccessible to their classical counterparts. The most famous example is the distribution of secret key. However, in the absence of quantum repeaters, the rate at which these tasks can be performed is dictated by the losses in the quantum channel. In practice, channel losses have limited the reach of quantum protocols to short distances. Quantum repeaters have the potential to significantly increase the rates and reach beyond the limits of direct transmission. However, no experimental implementation has overcome the direct transmission threshold. Here, we propose three quantum repeater schemes and assess their ability to generate secret key when implemented on a setup using nitrogen-vacancy (NV) centers in diamond with near-term experimental parameters. We find that one of these schemes - the so-called single-photon scheme, requiring no quantum storage - has the ability to surpass the capacity - the highest secret-key rate achievable with direct transmission - by a factor of 7 for a distance of approximately 9.2 km with near-term parameters, establishing it as a prime candidate for the first experimental realization of a quantum repeater.Comment: 19+17 pages, 17 figures. v2: added "Discussion and future outlook" section and expanded introduction, published versio

Militärinterventionen : verheerend und völkerrechtswidrig. Möglichkeiten friedlicher Konfliktlösung

The overall aim with this thesis is to create a broader understanding of how the EMS tool works in local authorities. This means to study whether EMS is a useful tool for managing the environmental impact from the local authorities' activities and by highlighting its strengths and weaknesses as a tool. EMS is a tool that is used on a voluntary basis that aims at improving organisations' environmental performance. There are several standards for designing EMSs; however, this thesis focuses on EMSs designed according to the principles of the international standard ISO 14001 and the EU regulation Eco-Management and Audit Scheme (EMAS). The standards are based on a wide range of requirements. If these requirements are fulfilled, the organisation can choose to get its EMS certified by a third party. The EMS tool is frequently used in the private sector, and it is sometimes argued that it is designed for private (industrial) organisations. However, local authorities worldwide have shown an increased interest in EMSs since the mid 1990s. The EMS use in the private sector has been subject to some critique. For example, there is a risk that the tool is used only to get another certificate in order to increase their legitimacy, which means that there is a risk that the environmental issues are neglected. Until now, little academic research has been conducted concerning EMS use in local authorities. Therefore, it is interesting to study what approaches local authorities have to EMSs. Mainly Swedish local authorities have been studied for this thesis. Many Swedish local authorities have been using EMSs for a fairly long time, which means that they have a certain amount of experience from this using tool. The local authorities' approaches to EMS use have been studied from several perspectives using postal surveys, interviews, and case study methodology. This means that the research has a strong empirical foundation. The EMS use in Swedish local authorities is fairly common, since almost half of them are in the process of implementing EMSs in all or some of their departments. The main reason for implementing EMSs is to improve the structure of their environmental management. The local authorities often use ISO 14001 and/or EMAS as inspiration and design the EMSs according to their local conditions and ambitions, thus certification of the EMSs is seldom an aim. Although many local authorities seem to use EMSs in a reflective and sensible way, several barriers or difficulties - for example, maintaining continuity and ensuring follow-up of the environmental improvements - have been discovered. Furthermore, the EMSs that are being implemented often exclude environmental impact related to their exercise of authority since it is difficult and abstract. Including environmental impact related to these activities is often seen as a matter of maturity. To develop the organisations' EMSs, internal and external communication and interaction is experienced as very important. Such issues contribute to the EMS maturity processes, since the local authorities find new inspiration, knowledge, and motivation to further develop the EMS processes and, as a consequence, improve their environmental performance

Novel treatment strategies for chronic kidney disease: insights from the animal kingdom

Many of the >2 million animal species that inhabit Earth have developed survival mechanisms that aid in the prevention of obesity, kidney disease, starvation, dehydration and vascular ageing; however, some animals remain susceptible to these complications. Domestic and captive wild felids, for example, show susceptibility to chronic kidney disease (CKD), potentially linked to the high protein intake of these animals. By contrast, naked mole rats are a model of longevity and are protected from extreme environmental conditions through mechanisms that provide resistance to oxidative stress. Biomimetic studies suggest that the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) offers protection in extreme environmental conditions and promotes longevity in the animal kingdom. Similarly, during months of fasting, immobilization and anuria, hibernating bears are protected from muscle wasting, azotaemia, thrombotic complications, organ damage and osteoporosis - features that are often associated with CKD. Improved understanding of the susceptibility and protective mechanisms of these animals and others could provide insights into novel strategies to prevent and treat several human diseases, such as CKD and ageing-associated complications. An integrated collaboration between nephrologists and experts from other fields, such as veterinarians, zoologists, biologists, anthropologists and ecologists, could introduce a novel approach for improving human health and help nephrologists to find novel treatment strategies for CKD

Ending Slavery : Hierarchy, Dependency and Gender in Central Mauritania

»Ending Slavery« offers insights into the »how« of practices of slavery that persist in parts of Mauritania up to the present day. It brings to the light the gendered structures of Moorish slavery, and examines their impact on strategies and tactics designed to bring this institution to an end. Underlying this study is empirical data gathered during two periods of field research in rural central Mauritania. The analysis of life histories of slaves and freed slaves, but also of tributaries and free Moors plays a key role in the book

MCL-1 promiscuity and the structural resilience of its binding partners

MCL-1 and its natural inhibitors, the BH3-only proteins PUMA, BIM, and NOXA regulate apoptosis by interacting promiscuously within an entangled binding network. Little is known about the transient processes and dynamic conformational fluctuations that are the basis for the formation and stability of the MCL-1/BH3-only complex. In this study, we designed photoswitchable versions of MCL-1/PUMA and MCL-1/NOXA, and investigated the protein response after an ultrafast photo-perturbation with transient infrared spectroscopy. We observed partial $\alpha$-helical unfolding in all cases, albeit on strongly varying timescales (1.6~ns for PUMA, 9.7~ns for the previously studied BIM, and 85~ns for NOXA). These differences are interpreted as a BH3-only-specific "structural resilience" to defy the perturbation while remaining in MCL-1's binding pocket. Thus, the presented insights could help to better understand the differences between PUMA, BIM, and NOXA, the promiscuity of MCL-1 in general, and the role of the proteins in the apoptotic network