98 research outputs found
Passage-time distributions from a spin-boson detector model
No full textThe passage-time distribution for a spread-out quantum particle to traverse a specific region is calculated using a detailed quantum model for the detector involved. That model, developed and investigated in earlier works, is based on the detected particle's enhancement of the coupling between a collection of spins (in a metastable state) and their environment. We treat the continuum limit of the model, under the assumption of the Markov property, and calculate the particle state immediately after the first detection. An explicit example with 15 boson modes shows excellent agreement between the discrete model and the continuum limit. Analytical expressions for the passage-time distribution as well as numerical examples are presented. The precision of the measurement scheme is estimated and its optimization discussed. For slow particles, the precision goes like E-3/4, which improves previous E-1 estimates, obtained with a quantum clock model
Ankunfts- und Durchflugszeiten von einem Spin-Boson Detektor-Modell
No full textDie vorliegende Arbeit verfolgt ein zweifaches Ziel: Einerseits befasst sie sich mit der Behandlung von Zeitobservablen in der Quantenmechanik. Insbesondere beschäftigt sie sich mit der Anwendung eines konkreten Spin-Boson Detektor-Modells auf Ankunfts- und Durchflugszeiten. Andererseits untersucht sie die Möglichkeit, die Quantensprung-Methode auf ein Modell außerhalb ihres ursprünglichen quantenoptischen Rahmens zu erweitern. Sie untersucht auch mittels numerischer Beispiele, ob die Quantensprung-Methode, die ein Kontinuum von Bad-Moden verwendet, eine gute Approximation an Situationen verspricht, in denen man eigentlich mit einer Anzahl diskreter Bad-Moden konfrontiert ist.The aim of the present thesis is twofold: On one hand it considers the treatment of time observables in quantum mechanics. In particular, it is concerned with the application of a particular spin-boson detector model to arrival and passage times. On the other hand it explores the possibility of extending the quantum jump approach to a model beyond its original, quantum optical framework. It also examines by means of numerical examples whether the quantum jump approach, which employs a continuum of bath modes, promises to provide a good approximation to situations where one actually has to deal with a number of discrete bath modes
A Note on Case-Based Optimization with a Non-Degenerate Similarity Function
No full textThe paper applies the ��realistic-ambitious�� rule for adaptation of the aspiration level suggested by Gilboa and Schmeidler (1996) to a situation in which the similarity between the available acts is represented by a non-degenerate function. The paper shows that the optimality result obtained by Gilboa and Schmeidler (1996) in general fails. With a concave similarity function, the best corner act is chosen in the limit. Introducing convex regions into the similarity function improves the limit choice. A sufficiently fine similarity function allows to approximate optimal behavior with an arbitrary degree of precision.
Disclosure Regimes and Corporate Governance
No full textAs there is a strong relationship of disclosure regimes and corporate governance the internationally varying distribution of information rights can be interpreted as a function of different systems of corporate governance. A disclosure system comprises all legally recognized information claims that a system of corporate governance or a financial system furnishes financial contracting parties with: Both public disclosure and disclosure via private information channels may serve value-relevant information for suppliers of finance. An analysis within the framework of the New Institutional Economics brings about two findings: First, looking at the distribution of informational rights from a contractual perspective shows that the nexus of information rights formed by accounting and disclosure regulation and the distribution of power in the firm are mutually determining. For example, the main financing parties in Germany, banks and blockholders, have fairly good access to information via institutionalized internal information channels. Secondly, internationally accepted sets of accounting standards may improve the monitoring by markets. Nevertheless, accounting and disclosure regulation sometimes resemble a cookbook and should be transformed in a more principle-based and deductive system. Furthermore the whole institutional design of corporate governance should be based on realistic assumptions about human decision making to serve the intended purposes.
Synthesis of Bifunctional Boron-Lewis Acids - Thorough Investigation of the Adduct Formation with Pyrimidine
No full textRudlof J, Glodde T, Mix A, Neumann B, Stammler H-G, Mitzel NW. Synthesis of Bifunctional Boron-Lewis Acids - Thorough Investigation of the Adduct Formation with Pyrimidine. European Journal of Inorganic Chemistry . 2022: e202100842.Three bifunctional boron-Lewis acids based on a 1,2-diethynylbenzene backbone were synthesized using a tin-boron exchange protocol in good to very good yields. Complexation experiments with pyrimidine were thoroughly investigated using the example of 1,2-bis(benzo[d][1,3,2]dioxaborol-2-ylethynyl)benzene (3) in solution, in the solid phase and by quantum-chemical calculations. Two adducts were structurally investigated by X-ray diffraction experiments. DOSY-/VT-NMR experiments gave insight into the dynamic behaviour of the synthesized poly-Lewis acids with pyrimidine
Zusammenbringen was zusammengehört. 1.und 2.Phase der Lehramtsausbildung. PH-FR 2007/1
No full textZusammenbringen was zusammengehört: die 1. und 2. Phase der Lehramtsausbildung Helga Epp: Tag der Lehrerinnen- und Lehrerausbildung 2006 – Im Überblick Siegfried Specker: Grußwort aus dem Regierungspräsidium Marita Schocker-v. Ditfurth · Eva Woelki: Kontinuum der Lernerfahrungen statt biografischem Bruch Wolfgang Panzer · Gudrun Schönknecht: Professionelle Entwicklung im Bereich Pädagogik Jürgen Tille-Koch · Timo Leuders: Der Erwerb didaktischer Kompetenzen bei Mathematiklehrer/innen Manuel Bär · Jens Friedrich · Marco Oetken: Naturwissenschaftlicher Unterricht in Studium und Referendariat Silke Müller · Ingelore Oomen-Welke: Die Kompetenz, Deutsch zu unterrichten Nicole Kränkel-Schwarz · Ute Leoni · Eynar Leupold: Länderübergreifende Bildungsstandards Französisch Ursula Erdrich · Bernd Friedrich · Josef Nerb: Wie erkenne ich geeignete Lehrerinnen und Lehrer? Günter Ganz · Erwin Graf · Monika Neumann · Ralf Streicher: Leitbild und Zielsetzungen – Das Staatliche Seminar (Realschule) Sybille Schütte · Friedrich Gervé: Qualitätsentwicklung der schulpraktischen Ausbildung Timo Leuders: Schnittpunkte – Perspektiven für die Zusammenarbeit der fachdidaktischen Ausbildung in Mathematik Xaver Anders · Olivier Mentz: Kooperation für eine europäische Zukunft – Das Europalehramt Elke Storz · Olivier Mentz: Europalehramt in der Primarstufe – Ein Café Europe mit Folgen Rudolf Denk: Vom früheren Nebeneinander zu grenzüberschreitenden Kooperationen Gerd Bräuer: Auf die Textsorten des beruflichen Lebens vorbereiten – Bausteine eines Schreib-Curriculums im Studium Mechtild Fuchs: Mupaed-Führerschein – Eine Fortbildungsreihe für den Musikunterricht an der Grundschule Christa Röber: Rechtschreibung am Samstag – Eine Fortbildungsreih
Monetary Convergence And Risk Premiums In The EU Candidate Countries
No full textThis study examines the link between various monetary policy regimes and the ability to manage inflation and exchange rate risk premiums in the EU candidate countries as they undergo monetary convergence to the eurozone. The underlying hypothesis is that a system of 'flexible inflation targeting' may be an optimal policy choice for managing these two categories of risk. A model of inflation and exchange rate risk premiums within the context of inflation targeting is proposed. Recent trends in these risk premiums in Hungary, the Czech Republic and Poland are tested by using the GARCH(1,1) methodology.inflation risk premium, exchange rate risk premium, inflation targeting, monetary convergence, transition economies
Neurofilament Light Chain in Blood and CSF as Marker of Disease Progression in Mouse Models and in Neurodegenerative Diseases
No full textA majority of current disease-modifying therapeutic
approaches for age-related neurodegenerative
diseases target their characteristic proteopathic
lesions (a-synuclein, Tau, Ab). To monitor such
treatments, fluid biomarkers reflecting the underlying
disease process are crucial. We found robust increases
of neurofilament light chain (NfL) in CSF
and blood in murine models of a-synucleinopathies,
tauopathy, and b-amyloidosis. Blood and CSF NfL
levels were strongly correlated, and NfL increases
coincided with the onset and progression of the
corresponding proteopathic lesions in brain. Experimental
induction of a-synuclein lesions increased
CSF and blood NfL levels, while blocking Ab lesions
attenuated the NfL increase. Consistently, we also
found NfL increases in CSF and blood of human
a-synucleinopathies, tauopathies, and Alzheimer’s
disease. Our results suggest that CSF and particularly
blood NfL can serve as a reliable and easily
accessible biomarker to monitor disease progression
and treatment response in mouse models and
potentially in human proteopathic neurodegenerative
diseases
Author Correction: Combined inhibition of BET family proteins and histone deacetylases as a potential epigenetics-based therapy for pancreatic ductal adenocarcinoma
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