Ähnlichkeit und Definition bei Leibniz und Goodman

Diese Arbeit behandelt am Beispiel von Leibniz und Nelson Goodman das Verhältnis, in dem die jeweilige Lehre von der Definition mit dem Ähnlichkeitsbegriff zu stehen kommt. Eine Hintergrundproblematik stellt das Universalienproblem dar, bzw. die Wertschätzung des Ähnlichkeitsbegriffes. Genauso berechtigt die Frage: Ähnlichkeit oder Definition

Wittgensteins Witz. Zur Lesart der Philosophischen Untersuchungen

Die vorliegende Arbeit widmet sich einem in interpretatorischer Hinsicht und auch im prinzipiellen Zugang zu Wittgensteins Werk bisher etwas vernachlässigten Aspekt: dem des Witzes. Wie sich zeigt, umfasst dieser Aspekt in Wittgensteins späterer Philosophie eine große Bandbreite von Erscheinungsformen und zieht sich, mehr oder minder versteckt, durch weite Teile desselben. Angesichts dessen wird dieser Aspekt aus verschiedenen Blickwinkeln, wie dem der Komik, der Struktur und demjenigen konkreter (Sprach)Witze im Spätwerk Wittgensteins betrachtet. Die Untersuchung konzentriert sich vom Textkorpus her vor allem auf das sogenannte "Philosophiekapitel" der Philosphischen Untersuchungen, resp. die Philosophischen Untersuchungen selber mitsamt ihren Vorstufen. Miteinbezogen in die Argumentation sind nichtsdestotrotz auch Manuskripte des gesamten Nachlasses, der seit der "Bergen Electronic Edition" öffentlich zugänglich ist

Mimicking stochastic processes

Besonders in den letzten 15 Jahren hat das Interesse an \emph{Mimicking} von stochastischen Prozessen immens zugenommen, vor allem im Bereich Finanzmathematik. \emph{Mimicking} bedeutet im Wesentlichen, für einen gegebenen stochastischen Prozess $X$ einen anderen Prozess \wtilde{X} zu finden, der in allen eindimensionalen Randverteilungen gleich dem ursprünglichen Prozess ist. In der Finanzmathematik ist das nicht zuletzt deswegen von Interesse, da die Familie der eindimensionalen Randverteilungen des Preis-Prozesses einer Aktie eineindeutig der Menge aller Preise einer European call option auf diese Aktie entspricht. Ist der Mimicking-Prozess Markov, bezeichnet man ihn als Markov-Projektion des ursprünglichen Prozesses. In Kapitel 1 wird ein kurzer Abriss der stochastischen Analysis gegeben, vor allem der Theorie der Martingale, Markovprozesse und stochastischen Differentialgleichungen. Kapitel 2 beschäftigt sich mit Mimicking-Resultaten zur Brownschen Bewegung, dem wichtigsten stetigen stochastischen Prozess mit kontinuierlichem Zustandsraum. Es werden verschiedene Konstruktionen von \textit{fake Brownian motions} vorgestellt, die stetige wie auch nichtstetige Prozesse liefern. Schließlich wird die Brownsche Bewegung als eindeutiges, stetiges, starkes Markov-Martingal charakterisiert, das die entsprechenden Randverteilungen aufweist. In Kapitel 3 werden Mimicking Resultate zu Martingalen und Ito-Prozessen im Allgemeinen diskutiert. Sowohl für reellwertige Martingale als auch für $k$-dimensionale Ito-Prozesse beschreiben wir schließlich jeweils eine Klasse von Prozessen für die die Markov-Projektion wohldefiniert ist.The problem of mimicking stochastic processes has become popular over the last 15 years, pre-eminently in the context of mathematical finance. \emph{Mimicking} here roughly means: given a stochastic process $X$, find another process \wtilde{X} which is equal to the original process in all one dimensional marginals. In math-finance this is of particular interest since there is a one-to-one correspondence between the 1-d marginals of an asset price process and the prices of European call options on this asset. If the mimicking process is constructed as a Markov process, the procedure is called \emph{Markovian projection}. In Chapter 1 we give a brief summary of stochastic calculus, including martingale and Markov theory and some theory of stochastic differential equations. Chapter 2 is concerned with mimicking the most important continuous time process with continuous state space: Brownian motion. We discuss several constructions of fake Brownian motions, continuous and discontinuous ones. Furthermore, we characterize (linear) Brownian motion as the unique continuous strong Markov martingale having Brownian marginals. Chapter 3 enlarges the scope of processes to be mimicked to real valued martingales and k-dimensional Ito-processes. Both in the case of real valued martingales and in the case of k-dimensional Ito-processes, we identify the classes of processes for which the Markovian projection is well defined

Humor als Übersetzungsproblem bei multimedialen Texten

Die vorliegende Arbeit beschäftigt sich mit den Herausforderungen und Grenzen der Humorübersetzung bei multimedialen Texten. Die Problematik bei der Übertragung des englischen Humors wird am Beispiel der deutschen Synchronfassung von „Monty Python and the Holy Grail“ illustriert. Zur Bearbeitung des Themas wird die Skopostheorie, die im ersten Kapitel vorgestellt wird, herangezogen um herauszufinden, ob die Funktion der Unterhaltung in der deutschen Fassung erreicht wurde. Das zweite Kapitel gibt einen Überblick über multimediale Texte im Allgemeinen und die Synchronisation als Sonderform im Besonderen. Das dritte Kapitel ist Humor und dessen Übersetzung gewidmet. Es werden drei allgemeine Humortheorien, insbesondere die Inkongruenztheorie, sowie die Kulturspezifik des deutschen und englischen Humors im Detail beschrieben sowie verschiedene Ansätze der Humorübersetzung besprochen. Des Weiteren werden in Kapitel vier die Komikertruppe Monty Python vorgestellt und relevante Informationen zur Original- und Synchronfassung gegeben. Die Analyse in Kapitel fünf erfolgt durch die Gegenüberstellung einzelner Szenen der beiden Filme, wobei auf die Inkongruenztheorie zurückgegriffen wird. Im Zuge der Analyse wird besprochen inwiefern die deutsche Fassung abgeändert wurde, um diese für die ZieltextrezipientInnen ansprechender zu gestalten. Filmmaterial wird beigelegt.This thesis deals with the challenges and limits of humour translation in multimedial texts. The dubbed version of “Monty Python and the Holy Grail” (“Ritter der Kokosnuß”) serves as an example to point out the problems encountered when translating English and pythonesque humour into German. In Chapter One the skopos theory is presented and will be applied for the analysis in order to find out whether the function– to entertain the target text recipients – has been fulfilled. Chapter Two provides an overview of multimedial texts and the dubbing process. Chapter Three primarily deals with humour and its translation. An overview of the three main humour theories is provided; in addition, the theory of incongruence and culture-specifity of English and German humour are discussed in detail. Furthermore, this chapter presents various approaches regarding the translation of humour. Chapter Four focuses on the phenomenon of the group Monty Python and provides information on the English version “Monty Python and the Holy Grail” and the dubbed version “Die Ritter der Kokosnuß”. In Chapter Five various scenes of the original and the dubbed version are analysed in order to show how humorous elements were translated. The analysis discusses the changes and adaptations implemented in the German version to make the translation more appealing to target text recipients. Film material is provided together with the thesi

A New Thermosensitive smc-3 Allele Reveals Involvement of Cohesin in Homologous Recombination in C. elegans

The cohesin complex is required for the cohesion of sister chromatids and for correct segregation during mitosis and meiosis. Crossover recombination, together with cohesion, is essential for the disjunction of homologous chromosomes during the first meiotic division. Cohesin has been implicated in facilitating recombinational repair of DNA lesions via the sister chromatid. Here, we made use of a new temperature-sensitive mutation in the Caenorhabditis elegans SMC-3 protein to study the role of cohesin in the repair of DNA double-strand breaks (DSBs) and hence in meiotic crossing over. We report that attenuation of cohesin was associated with extensive SPO-11–dependent chromosome fragmentation, which is representative of unrepaired DSBs. We also found that attenuated cohesin likely increased the number of DSBs and eliminated the need of MRE-11 and RAD-50 for DSB formation in C. elegans, which suggests a role for the MRN complex in making cohesin-loaded chromatin susceptible to meiotic DSBs. Notably, in spite of largely intact sister chromatid cohesion, backup DSB repair via the sister chromatid was mostly impaired. We also found that weakened cohesins affected mitotic repair of DSBs by homologous recombination, whereas NHEJ repair was not affected. Our data suggest that recombinational DNA repair makes higher demands on cohesins than does chromosome segregation

Leptotene/Zygotene Chromosome Movement Via the SUN/KASH Protein Bridge in Caenorhabditis elegans

The Caenorhabditis elegans inner nuclear envelope protein matefin/SUN-1 plays a conserved, pivotal role in the process of genome haploidization. CHK-2–dependent phosphorylation of SUN-1 regulates homologous chromosome pairing and interhomolog recombination in Caenorhabditis elegans. Using time-lapse microscopy, we characterized the movement of matefin/SUN-1::GFP aggregates (the equivalent of chromosomal attachment plaques) and showed that the dynamics of matefin/SUN-1 aggregates remained unchanged throughout leptonene/zygotene, despite the progression of pairing. Movement of SUN-1 aggregates correlated with chromatin polarization. We also analyzed the requirements for the formation of movement-competent matefin/SUN-1 aggregates in the context of chromosome structure and found that chromosome axes were required to produce wild-type numbers of attachment plaques. Abrogation of synapsis led to a deceleration of SUN-1 aggregate movement. Analysis of matefin/SUN-1 in a double-strand break deficient mutant revealed that repair intermediates influenced matefin/SUN-1 aggregate dynamics. Investigation of movement in meiotic regulator mutants substantiated that proper orchestration of the meiotic program and effective repair of DNA double-strand breaks were necessary for the wild-type behavior of matefin/SUN-1 aggregates

DNA resection in eukaryotes: deciding how to fix the break

DNA double-strand breaks are repaired by different mechanisms, including homologous recombination and nonhomologous end-joining. DNA-end resection, the first step in recombination, is a key step that contributes to the choice of DSB repair. Resection, an evolutionarily conserved process that generates single-stranded DNA, is linked to checkpoint activation and is critical for survival. Failure to regulate and execute this process results in defective recombination and can contribute to human disease. Here, I review recent findings on the mechanisms of resection in eukaryotes, from yeast to vertebrates, provide insights into the regulatory strategies that control it, and highlight the consequences of both its impairment and its deregulation

Chromosome Painting Reveals Asynaptic Full Alignment of Homologs and HIM-8–Dependent Remodeling of X Chromosome Territories during Caenorhabditis elegans Meiosis

During early meiotic prophase, a nucleus-wide reorganization leads to sorting of chromosomes into homologous pairs and to establishing associations between homologous chromosomes along their entire lengths. Here, we investigate global features of chromosome organization during this process, using a chromosome painting method in whole-mount Caenorhabditis elegans gonads that enables visualization of whole chromosomes along their entire lengths in the context of preserved 3D nuclear architecture. First, we show that neither spatial proximity of premeiotic chromosome territories nor chromosome-specific timing is a major factor driving homolog pairing. Second, we show that synaptonemal complex-independent associations can support full lengthwise juxtaposition of homologous chromosomes. Third, we reveal a prominent elongation of chromosome territories during meiotic prophase that initiates prior to homolog association and alignment. Mutant analysis indicates that chromosome movement mediated by association of chromosome pairing centers (PCs) with mobile patches of the nuclear envelope (NE)–spanning SUN-1/ZYG-12 protein complexes is not the primary driver of territory elongation. Moreover, we identify new roles for the X chromosome PC (X-PC) and X-PC binding protein HIM-8 in promoting elongation of X chromosome territories, separable from their role(s) in mediating local stabilization of pairing and association of X chromosomes with mobile SUN-1/ZYG-12 patches. Further, we present evidence that HIM-8 functions both at and outside of PCs to mediate chromosome territory elongation. These and other data support a model in which synapsis-independent elongation of chromosome territories, driven by PC binding proteins, enables lengthwise juxtaposition of chromosomes, thereby facilitating assessment of their suitability as potential pairing partners

CDK targets Sae2 to control DNA-end resection and homologous recombination

DNA double-strand breaks (DSBs) are repaired by two principal mechanisms: non-homologous end-joining (NHEJ) and homologous recombination (HR)1. HR is the most accurate DSB repair mechanism but is generally restricted to the S and G2 phases of the cell cycle, when DNA has been replicated and a sister chromatid is available as a repair template2-5. By contrast, NHEJ operates throughout the cell cycle but assumes most importance in G1 (refs 4​, ​6). The choice between repair pathways is governed by cyclin-dependent protein kinases (CDKs)2,3,5,7, with a major site of control being at the level of DSB resection, an event that is necessary for HR but not NHEJ, and which takes place most effectively in S and G2 (refs 2​, ​5). Here we establish that cell-cycle control of DSB resection in Saccharomyces cerevisiae results from the phosphorylation by CDK of an evolutionarily conserved motif in the Sae2 protein. We show that mutating Ser 267 of Sae2 to a non-phosphorylatable residue causes phenotypes comparable to those of a sae2Δ null mutant, including hypersensitivity to camptothecin, defective sporulation, reduced hairpin-induced recombination, severely impaired DNA-end processing and faulty assembly and disassembly of HR factors. Furthermore, a Sae2 mutation that mimics constitutive Ser 267 phosphorylation complements these phenotypes and overcomes the necessity of CDK activity for DSB resection. The Sae2 mutations also cause cell-cycle-stage specific hypersensitivity to DNA damage and affect the balance between HR and NHEJ. These findings therefore provide a mechanistic basis for cell-cycle control of DSB repair and highlight the importance of regulating DSB resection