Interplay of topological phases in magnetic adatom-chains on top of a Rashba superconducting surface

We investigate the topological properties and the accessible Majorana fermion (MF) phases arising in a hybrid device consisting of a chain of magnetic adatoms placed on the surface of a conventional superconductor with Rashba spin-orbit coupling (SOC). By identifying the favored classical magnetic ground state of the adatom chain, we extract the corresponding phase diagram which exhibits an interplay of ferromagnetic (FM), antiferromagnetic (AFM) and spiral orders. We determine the parameter regime for which the FM or AFM phases dominate over the spiral and additionally become stable against thermal and quantum fluctuations. For the topological analysis we focus on the FM and AFM cases and employ a low-energy effective model relying on Shiba bound states. We find that for both magnetic patterns the hybrid system behaves as a topological superconductor which can harbor one or even two MFs per edge, due to chiral symmetry. As we show, the two magnetic orderings lead to qualitatively and quantitatively distinct topological features that are reflected in the spatial profile of the MF wavefunctions. Finally, we propose directions on how to experimentally access the diverse MF phases by varying the adatom spacing, the SOC strength, or the magnetic moment of the adatoms in consideration.Comment: 18 pages, 14 figure

Einfluss antiviraler Therapie auf das Outcome mechanisch beatmeter Patienten mit Nachweis von Herpes simplex Virus Typ 1 in der bronchoalveolären Lavage

Die Relevanz eines Nachweises von Herpes-simplex-Virus Typ 1 (HSV-1) im unteren Respirationstrakt bei kritisch kranken Patienten wird in der Fachgesellschaft kontrovers diskutiert. Bisher ist nicht endgültig geklärt, ob es sich um eine harmlose endogene Reaktivierung und Freisetzung des Virus unter Immunsuppression handelt, oder um eine echte klinische Infektion, welche auf den weiteren Krankheitsverlauf deutlich Einfluss nehmen kann. Der Einsatz antiviraler Substanzen wie Aciclovir oder Ganciclovir ist daher bei diesem Krankheitsbild umstritten. Das primäre Ziel der Studie ist es, den Stellenwert einer antiviralen Therapie bei Nachweis von HSV-1 im unteren Respirationstrakt bei kritisch kranken Patienten auf der Intensivstation zu untersuchen. Daher wird das Outcome der Patienten mit antiviraler Therapie und derer ohne antivirale Therapie verglichen, um einen möglichen Überlebensvorteil zu eruieren

Non-equilibrium quasiparticles and topological excitations in hybrid superconducting structures

We discuss the properties of a hybrid single electron turnstile, involving a small superconducting island sandwiched between normal metal leads. We theoretically model the charge transport and non-equilibrium quasiparticle distribution and compare with recent experimental findings. In the second part of the thesis we theoretically investigate chains of magnetic atoms on top of superconducting substrates and discuss the ability of the hybrid setup to harbor Majorana fermion excitations

Managing A Fishery Through Contract: Legal Issues Raised By Sector Operating Agreements In The New England Multispecies Fishery

New England boasts one of the most productive marine ecosystems in the world. It has a long and rich tradition of fishing and has supported large scale commercial fisheries for cod and other groundfish (e.g., haddock and flounder) for centuries. The region also has a less envious tradition of fishery management failures including the “collapse” of a number of groundfish stocks in the 1990s. Before 1977, the groundfish fishery was practically unregulated and was open to local and international fishing fleets alike. Overfishing caused dramatic declines in many fish stocks in New England and other regions, prompting passage of the Fishery Conservation Management Act (known as the Magnuson-Stevens Act), which allowed the federal government to regulate fisheries out to 200 miles. The Magnuson-Stevens Act (MSA) created a fishery system that revolved around regional management councils, which developed and implemented fishery management plans (FMPs) and directed fishermen in their activities. The New England Fishery Management Council (NEFMC) has management authority over the New England multispecies groundfish fishery. It implemented a series of fishery management plans for the northeastern United States. These plans adopted a broad suite of management measures designed to achieve the fishing mortality targets necessary to rebuild certain overfished stocks and aspired to meet other requirements of the MSA. When a regional council develops an FMP, the National Oceanic and Atmospheric Administration (NOAA) and the National Marine Fisheries Service (NMFS), acting on behalf of the Secretary of Commerce, evaluate it for compliance with the ten national standards set forth in the MSA, as amended by the Sustainable Fisheries Act (SFA). A 2001 lawsuit by the Conservation Law Foundation (CLF) against the Secretary of Commerce, NOAA, and NFMS alleged that plans for rebuilding groundfish stocks failed to meet the national standards. CLF argued that the plans failed to adequately mitigate overfishing practices or to comply with bycatch restrictions. The lawsuit’s settlement led to Amendment 13 of the FMP. Among other things, Amendment 13 made possible a new style of fishery management for the New England multispecies groundfish fishery, namely, the creation of harvesting cooperatives known as “sectors.” Sectors are a form of community-based fisheries management. They require that groups of fishermen join together and agree to manage themselves collectively. By law, fishermen are obliged to sign a formal contract setting forth the key terms of their cooperative arrangement. The novelty and complexity of these contracts requires specialized legal drafting. Pursuant to a grant from the National Sea Grant Law Center, the University of Maine School of Law, in partnership with the Gulf of Maine Research Institute, and the New England office of the Ocean Conservancy, convened a workshop in November 2007, to address key legal issues raised by sector operating agreements. This article summarizes the Sector Workshop’s proceedings by highlighting the major legal issues discussed at the meeting. Part II describes community-based management generally and sectors as a management tool for the New England multispecies fishery. Part III discusses the legal issues to be resolved in sector operating agreements and reflects some of the specific concerns and suggestions raised by the workshop participants. Part IV concludes with reflections on sectors as a management tool and provides information on resources for those in the New England multispecies fishing industry who are considering forming or joining a sector

The parity effect in Josephson junction arrays

We study the parity effect and transport due to quasiparticles in circuits comprised of many superconducting islands. We develop a general approach and show that it is equivalent to previous methods for describing the parity effect in their more limited regimes of validity. As an example we study transport through linear arrays of Josephson junctions in the limit of negligible Josephson energy and observe the emergence of the parity effect with decreasing number of non-equilibrium quasiparticles. Due to the exponential increase in the number of relevant charge states with increasing length, in multi-junction arrays the parity effect manifests in qualitatively different ways to the two junction case. The role of charge disorder is also studied as this hides much of the parity physics which would otherwise be observed. Nonetheless, we see that the current through a multi-junction array at low bias is limited by the formation of meta-stable even-parity states.Comment: 8 pages, 5 figure

Internet Privacy Law, Policy, and Practice: State, Federal, and International Perspectives

By the summer of 2000, an estimated 90 million United States citizens used the Internet regularly, at least 69 percent of whom purchased goods and services online. As electronic commerce grew, e-businesses implemented technologies to facilitate the online shopping experience. Such technologies included “cookies,” which are small files a website\u27s host computer places on a visitor\u27s hard drive. Cookies allow a website to “remember” information provided by the visitor—such as her password, email address, credit card number, and mailing address—so she does not have to reenter the data on her next visit. They also allow website operators to track a consumer\u27s purchasing habits, monitor how long she views pages on the site, and learn other information about the consumer while she explores the World Wide Web. In June 2001, experts in online privacy law and policy gathered for a conference hosted by the Technology Law Center at the University of Maine School of Law. The conference included a discussion on federal, state, and European privacy initiatives presented by the following panelists: Bryan Harris, former head of the Intellectual Property Division of the Commission of the European Communities and currently an adjunct professor of European Union Law at Franklin Pierce Law Center in Concord, New Hampshire; Laura Mazzarella, attorney in the Division of Financial Practices of the Federal Trade Commission\u27s Bureau of Consumer Protection; Mary Ellen Callahan, associate attorney in the Washington, D.C. office of Hogan & Hartson LLP, practicing in the areas of antitrust, consumer protection, and litigation; and James Tierney, former Attorney General for the State of Maine and currently a Fellow with the Cyberspace Law Institute. Susan Richey, Professor of Law at Franklin Pierce Law Center, moderated the discussion

Signature extension for sun angle, volume 1

The author has identified the following significant results. Within a restricted zenith sun angle range of 35 - 50 degrees, it was empirically observed that canopy reflectance is mainly Lambertian. Reflectance changes with crop stage were simple shifts in scale in the sun angle range. It was noted that sun angle variations depend on canopy characteristics. Effects of the vegetative canopy were most pronounced at the larger solar zenith angles (20 %). The linear sun angle correction coefficients demonstrate a dependency on both crop stage (15-20 %) and crop type (10-20 %). The use of canopy reflectance modeling allowed for the generation of a simulated data set over an extremely broad envelope of sun angles