4,830 research outputs found
Clause-Type, Force, and Normative Judgment in the Semantics of Imperatives
I argue that imperatives express contents that are both cognitively and semantically related to, but nevertheless distinct from, modal propositions. Imperatives, on this analysis, semantically encode features of planning that are modally specified. Uttering an imperative amounts to tokening this feature in discourse, and thereby proffering it for adoption by the audience. This analysis deals smoothly with the problems afflicting Portner's Dynamic Pragmatic account and Kaufmann's Modal account. It also suggests an appealing reorientation of clause-type theorizing, in which the cognitive act of updating on a typed sentence plays a central role in theorizing about both its semantics and role in discourse
Reasoning about Knowledge in Context
In this paper we propose a new semantics, based on the notion of a "contextual model", that makes it possible to express and compare â within a unique formal framework â different views on the roles of various notions of context in knowledge ascriptions. We use it to provide a logical analysis of such positions as skeptical and moderate invariantism, contextualism, and subject-sensitive invariantism. A dynamic formalism is also proposed that offers new insights into a classical skeptical puzzle
Herstellung eines Phaffia rhodozyma : Stamms mit verstĂ€rkter Astaxanthin-Synthese ĂŒber gezielte genetische Modifikation chemisch mutagenisierter StĂ€mme
Ziel dieser Arbeit war es erstmals durch eine Kombination aus chemischer Mutagenese und gezielter genetischer Modifikation (hier: âmetabolic engineeringâ) einen Phaffia-Stamm herzustellen, welcher ĂŒber die Mutagenese hinaus ĂŒber eine weiter verstĂ€rkte Astaxanthin-Synthese verfĂŒgt.
Die von âDSM Nutritional Productsâ bereitgestellten chemischen Mutanten wurden analysiert und ĂŒber einen Selektionsprozess auf PigmentstabilitĂ€t und Wachstum hin optimiert, da die StĂ€mme aus cryogenisierter Dauerkultur starke PigmentinstabilitĂ€ten und ein verzögertes Wachstum aufwiesen.
Ăber eine exploratorische Phase wurde die Carotinoidsynthese analysiert und festgestellt, dass in den Mutanten keine Einzelreaktionen betroffen sind, welche fĂŒr die Heraufregulierung der Carotinoidsynthese in den Mutanten verantwortlich sind. Hierbei wurden Limitierungen identifiziert und diese durch Transformation von Expressionsplasmiden mit geeigneten Genen aufgehoben, um damit eine noch effizientere Metabolisierung von Astaxanthin-Vorstufen hin zu Astaxanthin zu erreichen. Eine Ăberexpression der Phytoensynthase/Lycopinzyklase crtYB resultierte in einem gesteigerten Carotinoidgehalt bei gleichbleibendem Astaxanthin- Anteil. Durch eine zweite Transformation mit einer Expressionskassette fĂŒr die Astaxanthin-Synthase asy konnte der Carotinoidgehalt weiter gesteigert und zusĂ€tzlich eine Limitierung der Metabolisierung von Astaxanthin-Vorstufen behoben werden, sodass die Transformante nahezu alle Intermediate der Astaxanthinsynthese zu Astaxanthin metabolisieren konnte (Gassel et al. 2013). Es konnte gezeigt werden, dass auch in den Mutanten, aus Experimenten mit dem Wildtyp bekannte, Limitierungen identifiziert und ausgeglichen werden konnten
Lockeans Maximize Expected Accuracy
The Lockean Thesis says that you must believe p iff youâre sufficiently confident of it. On some versions, the 'must' asserts a metaphysical connection; on others, it asserts a normative one. On some versions, 'sufficiently confident' refers to a fixed threshold of credence; on others, it varies with proposition and context. Claim: the Lockean Thesis follows from epistemic utility theoryâthe view that rational requirements are constrained by the norm to promote accuracy. Different versions of this theory generate different versions of Lockeanism; moreover, a plausible version of epistemic utility theory meshes with natural language considerations, yielding a new Lockean picture that helps to model and explain the role of beliefs in inquiry and conversation. Your beliefs are your best guesses in response to the epistemic priorities of your context. Upshot: we have a new approach to the epistemology and semantics of belief. And it has teeth. It implies that the role of beliefs is fundamentally different than many have thought, and in fact supports a metaphysical reduction of belief to credence
A Montagovian Treatment of Modal Subordination
International audienceEpistemic modality involves complex contextual dependencies that linguists have studied (Roberts 1989; Veltman 1996). We show that they have a natural treatment within a continuation style semantics.Les modalitĂ©s Ă©pistĂ©miques mettent en Ćuvre des dĂ©pendances contextuelles complexes que les linguistes ont dĂ©jĂ Ă©tudiĂ©es (Roberts 1989, Veltman 1996). Nous montrons qu'elles ont un traitement naturel avec une sĂ©mantique utilisant les continuations
Semantic monsters
This chapter provides a general overview of the issues surrounding so-called semantic monsters. In section 1, I outline the basics of Kaplanâs framework and spell out how and why the topic of âmonstersâ arises within that framework. In Section 2, I distinguish four notions of a monster that are discussed in the literature, and show why, although they can pull apart in different frameworks or with different assumptions, they all coincide within Kaplanâs framework. In Section 3, I discuss one notion that has spun off into the linguistics literature, namely âindexical shiftâ. In Section 4, I emphasize the connection between monsters and the compositionality of asserted content in Kaplanâs original discussion. Section 5 discusses monsters and the more general idea of re-interpretation or meaning-shift. Section 6 closes with a brief survey of where monsters may dwell, and pointers to avenues for future research
Modus Ponens and the Logic of Decision
If modus ponens is valid, then you should take up smoking
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