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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Marc teòric de les controvèrsies científiques: el cas de la sacarina

Vallverdú, Jordi, 1973- 27 May 2002 (has links)
La tesi doctoral s'emmarca dins el marc teòric dels estudis de Ciència, Tecnologia i Societat, concretament en els Estudis de Controvèrsies Científiques. L'autor aporta un model d'anàlisi de les controvèrsies que abarca la identificació, la dinàmica i la clausura de les controvèrsies, tot contribuint a establir els paral·lelismes entre la dinàmica evolutiva de la macrociència i la microciència. El disseny d'un marc d'anàlisi holístic requereix per part de l'autor la inclusió en el model filosòfic de les àrees de la ciència industrial, els medis de comunicació i la societat civil. Els canvis estructurals esdevinguts en les principals nacions mundials durant finals del segle XIX i la totalitat del segle XX, han menat a la era de la informació i a una modificació radical en la dinàmica científica, que el present model recull. L'existència de diversos agents i tipus de controvèrsies, delimitables a partir del model proposat, justifica la idea de camps de controvèrsies, en el que trobaríem diversos tipus de controvèrsies situades en nivells socials, temporals i epistèmics diferents.L'autor il·lustra el model teòric a partir d'un estudi de cas històric, el de la sacarina, el primer edulcorant de síntesi no nutritiu que es trobà envoltat de la polèmica des del seu descubriment, l'any 1878, fins el desembre de 2000. El cas abarca un lapse temporal suficientment extens per tal que l'estudi permeti observar la necessitat de la inclusió d'aquests nous agents en el model d'anàlisi teòric. A més de realitzar un anàlisi epistemològic respecte la dinàmica de les controvèrsies científiques, l'autor dedica dos capítols a l'anàlisi intern de la metodologia científica emprada en l'intent de clausura de la controvèrsia sobre les suposades propietats tòxiques de la sacarina. La tesi doctoral inclou annexos que contemplen la percepció de la controvèrsia dins la premsa, la literatura, l'humor o Internet.L'autor manifesta la necessitat de comprendre la dinàmica científica a partir dels moments de crisi, les controvèrsies en el cas de la microdinàmica, i de la utilitat del concepte de camps de controvèrsies. Indica també la idea del caràcter obert i revisable dels models teòrics d'anàlisi de la ciència, i de la natura dinàmica dels processos científics. / The present Thesis belongs to the Science, Technology and Society Studies and, more to the point end of to the Scientific Controversies Studies. The author introduces a controversy analysis model that analizes the controversies identification, dynamics and closure, and contributes to show the parallelism between the dynamic evolution of macro- and microscience. The design of an holistic analysis frame involves the inclusion, inside the philosophical model, of industrial science, mass media and civil society. Structural changes appeared through the main developed countries from the XIXth Century and the full XXth Century have led to the Information Era and to a radical transformation of the scientific dynamic, both aspects analyzed by the present model. The existence of several kinds of controversies and agents involved, easily outlined by means of the proposed model, justifies the idea of controversy fields, in which we could find several kind of controversies with different social, temporal and epistemic levels.The author illustrates this theoretical model using the saccharin historic case study. Saccharin was the first synthetic non-nutritive sweetener, and founded itself involved from the years of its discovery, 1878, until the 2000's end. The case spans for an extremely large period, which allows the necessity to include new agents inside the theoric model. The author developes an epistemological study on scientific controversies dynamic as well as the true scientific techniques used by scientists through the saccharin toxicological controversies. Two whole chapters, one devoted to the historical case study, and several Annexes also included show the controversies perception about saccharin on journals, literature, cartoonists and the Internet.Finally, the author remarks the necessity to understand the scientific dynamics in the polemical periods, controversies at the microscience level, and insists on the utility of the 'controversies field' concept. He also remarks the necessity to undertand philosophical models of scientific dynamics as open and checkable processes, and to recognize the dynamical nature of scientific processes.
282

Self-Involving Representationalism (SIR): A naturalistic Theory of Phenomenal Consciousness

Sebastián González, Miguel Ángel 17 June 2011 (has links)
A naturalistic account of phenomenal consciousness is presented: Self-Involving Representationalism. The first step for the project of naturalizing phenomenal consciousness is to make the project itself feasible. The purpose of the fi rst part of this work is to provide a suitable answer to some arguments presented against this enterprise. I discuss the classical modal and knowledge argument and defend the phenomenal concept strategy against objection by Tye and Chalmers. I also consider some arguments from vagueness against the project. In the second part I will develop the pillars of the theory. In order to make compatible the intuition that phenomenal properties are intrinsic properties of the subject and explain cases of shifted spectrum I appeal following Shoemaker to appearance properties and I follow Egan in the characterization of this properties. According to Self-Involving Representationalism, phenomenally conscious mental states are states that represent a speci c kind of de se content. I argue that in having an experience I do not merely attribute certain properties to the object causing the experience, I attribute to myself being presented with an object with these properties. This content can be naturalized in rst-order terms by appealing to a certain sense of self: the sense of a bounded, living organism adapting to the environment to maintain life and the processes underlying the monitoring of the activity within these bounds.
283

Poder y subjetividad. Un discurso vivo

Garay Uriarte, Ana Isabel 23 November 2001 (has links)
Esta tesis parte de. una inquietud por el sentido de la propia actividad, de la producción científica; una inquietud por los procesos de subjetivación, de la configuración de nuestros yoes, de nuestras vidas en un entramado de relaciones de poder y de dominación que, dificultan esa vida; una inquietud por el papel que la actividad en tanto que psicólogos y psicólogas sociales tiene en ese entramado de subjetivación y de mantenimiento de un status quo. El modelo epistemológico aporta un acercamiento a las preguntas sobre el sentido, un sentido dirigido por el lenguaje, por la historicidad y la reflexividad.En la tesis se presentan narraciones de las ciencias sociales y humanas sobre la constitución del yo. Se resaltan las aportaciones de Mead, Elias y Foucault, resaltando la lectura procesual del sí mismo, así como la constitución eminentemente social de la persona. Dada la preocupación por los sistemas y prácticas de poder vinculadas a la subjetivación, el texto se acerca a la descripción de estrategias de poder, a las tecnologías de la gubernamentalidad: la disciplina, la biopolítica y a las tecnologías neoliberales de poder. El interés de esta descripción es la aproximación a explicaciones que de manera explícita plantean los mecanismos productivos del poder, aquellos que construyen subjetividad. Se defiende que el proceso de dominación más brutal en la modernidad ha sido y sigue siendo la individualización, el olvido o descuido de las relaciones sociales, esa tendencia conjunta hacia una totalitarización y ultraindividualización de la vida. A modo de un acercamiento concreto a las tecnologías de subjetivación contemporáneas, el texto se adentra en el mundo del mercado y su racionalización como un gran eje de control, gubernamentalidad y poder, como proceso generador de exclusiones, malestares y muerte. Se expone cómo la ética del trabajo, del empleo en estos momentos tiene efectos de dominación y exclusión; y cómo en ese proceso existen rehenes y chantajes. A la vez, cómo esa racionalización, sustentada por la lógica de la eficacia y el beneficio, construye en su hacer el sujeto "hegemónico" que necesita: un sujeto flexible, capaz de adaptarse -a lo que sea-, un sujeto con la libertad dada por el mercado, capaz de asumir y gestionar los riesgos, individuo cada vez más castigado o penado por su dependencia, y por la expresión de su necesidad de los otros. Ante esta lectura del mundo, se recogen las propuestas que invitan a separar el dinero y el trabajo; a entender la independencia entre el derecho a un ingreso necesario para vivir y la capacidad de obtenerlo por medio del mercado, y aquellas propuestas que reivindican lo colectivo, la narración conjunta de la dificultad como horizonte de sentido y posibilidad de emancipación. / This research proceeds from a question about the sense of our own activity of scientific production; a question about the subjectification processes, about the processes of configuration of our "I's", of our lives in a net of power and domination relations that conform the difficulties of this life; a question about our role as social psychologists in this net of subjectification and the maintenance of status quo. The epistemological model contributes to the questions about the processes of making sense, a sense directed by language, by historicity and reflexivity. In this research, some accounts about the processes of self constitution taken from social and human sciences are presented. Contributions of Mead, Elias and Foucault are emphasised, taking in account the procesual character of the self and also the accounts of the eminent social constitution of the self, made by these authors. Departing from the interest on the systems and practices of power related to the processes of subjectification, the text makes an account on power strategies and governmentality technologies: discipline, biopolitics and the neoliberal technologies of power. The interest of this account is the approximation to explanations that work explicitly with the productive mechanisms of power that construct subjectivity. It is defended that the most rough process of domination in modernity has been and is the process of individuation, the oversight or neglect of social relations and the overall tendency towards a totalization and ultraindividuation of life. For a specific approach to the contemporary technologies of subjectification, in this text the market world is worked in relation with it's rationalisation as a core of control, governmentality and power, as processes that generate exclusions, discomfort and death. An account is worked about how the work ethics in this historical moment has effects of domination and exclusion and how in this process hostages and blackmails are produced. It is also worked how this rationalisation, supported by efficacy and benefit logic, constructs day to day the "hegemonic" subject that needs: a flexible subject, capable to adapt to any condition, a subject who's liberty is given by market, capable to assume and to negotiate with risks, an individual punished because of s/he's dependence and because of the expression of his/her necessity of others. Taken this reading of the world, some suggestions are exposed such as the separation of money and work: there is an invitation to understand the independence between the right to a necessary income for a living and the capacity of obtaining such income by means of market. Also some propositions are made that claim the possibility of rethinking collective processes, the possibility of making collective narratives of difficulty as a way of making sense to our lives and as a possibility of emancipation.
284

Nombres, referencia y valor cognoscitivo

Vicario Arjona, Ignacio 14 September 2001 (has links)
El tema de la tesis doctoral concierne a la semántica de los nombres propios y, principalmente, se centra en el estudio de algunos problemas cognoscitivos derivados de su comprensión. El punto de vista defendido es que los nombres (además de referir directamente) son términos millianos: su significado no incorpora connotaciones o material predicativo sobre el referente. No obstante, mi análisis se aleja de posturas millianas simplistas para las que dar con el referente es suficiente para comprender un nombre. Arguyo que en la comprensión de un nombre, aparte del referente y de los rasgos gramaticales, es fundamental qué nombre (entidad lingüística) ha sido proferido: individualización que no depende meramente de su portador o de sus propiedades ortográfico-fonológicas, y que, esencialmente, incluye una cadena de comunicación. Así, las diferencias lingüísticas no comportan, necesariamente, diferencias semánticas. La relevancia del análisis radica en que satisface las condiciones para que se produzca una genuina comprensión (posibilita la transmisión de conocimiento), y en que supera, entre otras, las dificultades cognoscitivas que plantea R.Heck (con nombres homónimos correferentes), sin haber de exigir una similitud en los modos de presentación de los hablantes. El nexo comunicativo entre los interlocutores no pasa por la similitud predicativa, sino por las relaciones externas que (a través de las cadenas de comunicación) mantienen las concepciones sobre el referente de los hablantes.Otras cuestiones y principales aportaciones:l) Mantengo que la referencialidad es una propiedad de los términos en virtud de pertenecer a un determinado tipo lingüístico. Examino críticamente una interpretación epistémica de la referencia (G.Evans, a partir de Russell) que presupone una noción epistémica del contenido de una aseveración. Desde esta perspectiva, un término es referencial para un oyente si su conocimiento del designátum es objeto-dependiente. A ello opongo una interpretación semántica, basada en aquello que hace verdadera o falsa una aseveración (en distintas circunstancias contrafácticas). Muestro, contra Evans (y otros), que la noción epistémica de contenido no está tan desligada de la semántica (defendiendo así el argumento modal). 2) Propongo un análisis de los nombres introducidos por descripción ("Julius") que permite un tratamiento referencial unitario de los nombres en general, con relación a su significado y a las condiciones para su comprensión; de suerte que no se establecen diferencias en sus propiedades semánticas, ya fueran introducidos por descripción u ostensión, ni entre hablantes en virtud de su mayor o menor conocimiento de los designata.3) Dilucido la noción de referencia directa (centrada en la condición de verdad), y la separo de la noción de designación rígida (relativa al objeto designado en diferentes circunstancias contrafácticas, con independencia de si es parte de la condición de verdad) y de rigidizaciones descriptivistas.4) Distingo dos aspectos en la noción de millianidad: no-connotatividad (ausencia de alguna descripción del designátum) e inmediatez, (ausencia de material descriptivo cuyo fin es seleccionar la designación). Eludiendo, así, confusiones argumentativas que mezclan consideraciones sobre los efectos cognoscitivos en la comprensión con la cuestión de la determinación del designátum (p.ej. en la discusión sobre la referencialidad de "Julius".)5) Sostengo que el modelo no-descriptivo de designación no elimina el componente intencional: sólo rechaza que las intenciones comunicativas se interpreten como intenciones (predicativamente) individualizadoras. Destaco otro tipo de intención: la de preservar y ajustarse (deferentemente) a los usos lingüísticos de una comunidad. Analizo la estructura y función (metasemántica) de las cadenas de comunicación (liberándolas de objeciones tipo "Madagascar" e interpretaciones descriptivistas).6) Dilucido el modelo de designación de los nombres, separándolo del que corresponde a los deícticos, y critico las teorías connotativistas metalingüísticas.7) Reexamino, mostrando sus fallas, la argumentación de Frege acerca del problema del valor cognoscitivo. (Y defiendo la pertinencia del caso "Paderewski" para el millianismo.)
285

Dir i implicar no lògicament

Domingo Belando, Ambròs 13 December 2005 (has links)
La tesi s'ocupa de qüestions centrals relacionades amb la distinció entre semàntica i pragmàtica. En primer lloc aborda la distinció entre allò que es diu i allò que s'implica no lògicament amb la proferència d'un enunciat, i després, i en base a la manera com s'estableix aquesta distinció, s'ocupa dels diferents fenòmens d'implicació no lògica.En la primera part del treball s'introdueix primer la distinció entre allò que es diu i allò que s'implica de manera no lògica. Es mostra com una posició griceana, a mig camí entre posicions semanticistes i pragmatistes extremes, resulta més adequada que aquestes últimes si el que es vol és explicar de quina manera els enunciats que proferim són portadors del contingut que volem comunicar (tant del contingut que es diu com del contingut que s'implica de manera no lògica). Les principals aportacions d'aquesta primera part són: (1) la defensa d'una posició de tall griceà, si bé no estrictament dins dels paràmetres sostinguts per Grice, davant de posicions més semanticistes o més pragmatistes; al llarg de la discussió (2) s'introdueixen algunes modificacions al marc griceà i, dins d'aquest marc modificat, (3) es proposen directrius per resoldre el càlcul de quines de les implicacions no lògiques de les clàusules que constitueixen un enunciat compost són, al seu torn, implicacions no lògiques de la proferència del propi enunciat compost -el que es coneix amb el nom de 'problema de la projecció'. Finalment, (4) es presenten algunes dificultats importants tant per a plantejaments semanticistes com per a propostes pragmatistes més extremes que la griceana.En la segona part del treball, i prenent com a referència la distinció entre allò que es diu i allò que s'implica no lògicament que s'ha defensat abans, es consideren diferents tipus d'implicacions no lògiques presents en la literatura. Les principals aportacions d'aquesta segona part són: (5) l'anàlisi del fenomen de la implicatura conversacional. S'introdueix primer el fenomen tal i com el concebé en el seu origen Grice i es posen de manifest les dificultats d'aquesta caracterització originària; l'anàlisi condueix a formular una nova caracterització del fenomen que evita els problemes en qüestió; (6) la tesi que el contingut d'una implicatura convencional no pot constituir part d'allò que s'implica no lògicament per mitjà de la proferència d'un enunciat, sinó part d'allò que es diu, la qual cosa comporta (7) haver de reconèixer dos nivells diferents en l'anàlisi d'allò que es diu. La consideració d'aquests dos nivells permet, d'altra banda, explicar l'estranyesa que es produeix quan la proposició que constitueix una implicatura convencional (o una pressuposició) de la proferència d'un enunciat resulta ser falsa. Per explicar aquesta estranyesa cal també tenir present (8) la distinció precisa entre generalització i convenció, sobretot al respecte de la separació entre implicatures convencionals (o pressuposicions) i implicatures conversacionals generalitzades. En el treball es donen raons explicatives de per què es produeix una aparent similitud entre tots dos fets, la generalització i la convenció, si bé en realitat són, se sosté, de naturalesa ben diferent. / The thesis deals with some central questions related to the distinction between pragmatics and semantics. Firstly, it examines ways of establishing the distinction between what is said and what is implicated. Secondly, in accordance with the way the former distinction is traced, it accepts only some of the traditionally considered phenomena of implication and characterizes them.In the first part of this work, the distinction between what is said and what is implicated is presented. Here, (1) I try to defend a Gricean view against other positions which are either more semanticists or more pragmatists; (2) during the discussion, I introduce some modifications to the purely Gricean proposal; and (3) I propose a solution, within the suggested modified Gricean framework, allowing for the determination of the implications of the clauses of a compound sentence that are inherited by the utterance of the compound sentence itself -the so-called 'projection problem'; finally, (4) some strong objections are raised against both strictly semanticist views and, above all, pragmatist approaches.Following the previously sustained distinction between saying and implicating, in the second part of the work different types of non-logic implications are considered. The main points of this part are: (5) a characterization of the conversational implicature that tries to avoid the problems of the notion as Grice introduced it; (6) the thesis that the content of a conventional implicature cannot be a part of what is implicated in uttering a sentence, but only a part of what is said; as a consequence, (7) the idea that we need to consider two different levels in the analysis of what is said; and (8) the reasons of the apparent similarity between generalization and convention when dealing with conventional and conversational generalized implicatures.
286

Duality Theory and Abstract Algebraic Logic

Esteban, María 04 November 2013 (has links)
In this thesis we present the results of our research on duality theory for non-classical logics under the point of view of Abstract Algebraic Logic (AAL). Firstly, we propose an abstract Spectral-like duality and an abstract Priestley-style duality for every filter distributive finitary congruential logic with theorems. This proposal aims to unify the various dualities for concrete logics that we find in the literature, by showing the abstract template in which all of them fit. Secondly, the dual correspondence of some logical properties is examined. This serves to reveal the connection between our abstract dualities and the concrete dualities related wot concrete logics. We apply those results to get new dualities for suitable expansions of a well-known logic: the implicative fragment of intuitionistic logic. Finally, we develop a new strategy that can be modularly applied to simplify some of the dualities obtained. The first part of the dissertation is devoted to introduce the preliminaries and the basic notation. In Chapter 1 we fix the mathematical concepts that we assume the reader is familiar with. Of particular interest is the section in which we introduce the basic concepts of AAL, such as "S-filter" or "S-algebra". The notion of "closure operator" plays a fundamental role in AAL, as well as in our dissertation. The notions of filter and ideal associated with a closure operator, and the separation lemmas between them are studied in detail in Chapter 2. Moreover, we briefly review the literature on duality theory for non classical logics in Chapter 3. In the second part of the dissertation we present an abstract view of the duality theory for non-classical logics. In Chapter 4 we review previous works on this topic, in which our work relies, and we introduce the notions of "referential algebra", "irreducible and optimal S-filter" and "S-semilattice". This lead us to identify a set of necessary conditions that a logic should satisfy in order to develop a Spectra-like/Priestley-style duality for it. These conditions are: "filter distributivity","congruentiality", "finitarity" and "having theorems". Moreover, we carry out a brief digression in which we argue how those notions can also be used to develop an abstract theory of canonical extensions. The core of the proposed theory consists of the definitions of dual objects and morphisms, for the category of S-algebras and homomorphisms, for any logic S that satisfies the mentioned properties. In Chapter 5 we define a Spectral-like duality and a Priestley-style duality for filter distributive finitary congruential logics with theorems, and we prove the respective duality theorems. Due to the abstraction of our approach, we obtain that the objects of both categories involved in the duality posses algebraic nature. However, through the analysis of the dual correspondence of several well-known logical properties, we can simplify the definitions of the dual categories, provided the logic under consideration satisfies such good logical properties. This analysis is interesting under the point of view of AAL, since our results can be regarded as bridge theorems between logical properties and properties of a Kripke-style semantics. And it is also interesting under the point of view of duality theory, since it confirms the strength of duality theory, that can be developed in a modular way beyond the distributive lattice setting. Moreover, our analysis shows the connection of the general theory proposed with the concrete results that we find in the literature, and lead us to explore the applications of such general theory to obtain new dualities. / En esta tesis se presentan los resultados de nuestra investigación acerca de la teoría de la dualidad para lógicas no clásicas desde el punto de vista de la Lógica Algebráica Abstracta (LAA). Un estudio preliminar de las distintas nociones de filtros e ideales lógicos asociados a las álgebras de una lógica cualquiera, y los lemas de separación entre dichas nociones nos lleva a proponer una dualidad abstracta de tipo espectral, y otra de tipo Priestley, para cada lógica congruencial, filtro distributiva, finitaria y con teoremas. Esta propuesta pretende unificar las distintas dualidades de tipo espectral y de tipo Priestley para lógicas no clásicas que encontramos en la literatura, mostrando el esquema abstracto en el que todas ellas encajan e identificando. En segundo lugar es examinada la correspondencia dual de algunas propiedades lógicas, como la propiedad de la conjunción, la propiedad de la disyunción, el teorema de deducción, la propiedad del elemento inconsistente o la propiedad de introducción de la modalidad. Esto sirve, por una parte, para revelar la conexión que existe entre las dualidades abstractas propuestas y las dualidades concretas relacionadas con lógicas no clásicas que habían sido estudiadas previamente, y por otra parte, para obtener nuevas dualidades. Centrándonos en el fragmento implicativo de la lógica intuicionista y en sus expansiones que son filtro distributivas, congruenciales, finitarias y con teoremas, mostramos cómo las dualidades que habían sido estudiadas para algunas de esas lógicas se pueden obtener como casos particulares de la teoría general. Además obtenemos nuevas dualidades para varias de dichas expansiones, algunas de las cuales pueden ser simplificadas dado que las lógicas tienen buenas propiedades. Finalmente, desarrollamos una nueva estrategia que puede ser aplicada de forma modular para simplificar algunas de las dualidades obtenidas. En conclusión, en esta tesis se muestra que la Lógica Algebráica Abstracta provee un marco general teórico apropiado para desarrollar una teoría abstracta de la dualidad para lógicas no clásicas. Dicha teoría uniformiza los diferentes resultados de la literatura, y de ella se deducen nuevos resultados.
287

Large cardinals and resurrection axioms

Tsaprounis, Konstantinos 14 December 2012 (has links)
In the current dissertation we work in set theory and we study both various large cardinal hierarchies and issues related to forcing axioms and generic absoluteness. The necessary preliminaries may be found, as it should be anticipated, in the first chapter. In Chapter 2, we study several C(n) - cardinals as introduced by J. Bagaria (cf. [1]). In the context of an elementary embedding associated with some fixed C(n) - cardinal, and under adequate assumptions, we derive consistency (upper) bounds for the large cardinal notion at hand; in particular, we deal with the C(n) - versions of tallness, superstrongness, strongness, supercompactness, and extendibility. As far as the two latter notions are concerned, we further study their connection, giving an equivalent formulation of extendibility as well. We also consider the cases of C(n) -Woodin and of C(n) – strongly compact cardinals which were not studied in [1] and we get characterizations for them in terms of their ordinary counterparts. In Chapter 3, we briefly discuss the interaction of C(n) – cardinals with the forcing machinery, presenting some applications of ordinary techniques. In Chapter 4, we turn our attention to extendible cardinals; by a combination of methods and results from Chapter 2, we establish the existence of apt Laver functions for them. Although the latter was already known (cf. [2]), it is proved from a fresh viewpoint, one which nicely ties with the material of Chapter 5. We also argue that in the case of extendible cardinals one cannot use such Laver functions in order to attain indestructibility results. Along the way, we give an additional characterization of extendibility, and we, moreover, show that the global GCH can be forced while preserving such cardinals. In Chapter 5, we focus on the resurrection axioms as they are introduced by J.D. Hamkins and T. Johnstone (cf. [3]). Initially, we consider the class of stationary preserving posets and, assuming the (consistency of the) existence of an extendible cardinal, we obtain a model in which the resurrection axiom for this class holds. By analysing the proof of the previous result, we are led to much stronger forms of resurrection for which we introduce a family of axioms under the general name “Unbounded Resurrection”. We then prove that the consistency of these axioms follows from that of (the existence of) an extendible cardinal and that, for the appropriate classes of posets, they are strengthenings of the forcing axioms PFA and MM. We furthermore consider several implications of the unbounded resurrection axioms (e.g., their effect on the continuum, for the classes of c.c.c. and of sygma- closed posets) together with their connection with the corresponding ones of [3]. Finally, we also establish some consistency lower bounds for such axioms, mainly by deriving failures of (weak versions of) squares. We conclude our current mathematical quest with a few final remarks and a small list of open questions, followed by an Appendix on extenders and (some of) their applications. References [1] Bagaria, J., C (n)–cardinals. In Archive Math. Logic, Vol. 51 (3–4), pp. 213–240, 2012. [2] Corazza, P., Laver sequences for extendible and super–almost–huge cardinals. In J. Symbolic Logic, Vol. 64 (3), pp. 963–983, 1999. [3] Johnstone, T., Notes to “The Resurrection Axioms”. Unpublished notes (2009).
288

Logical planning in Temporal Defeasible and Dynamic Epistemic Logics: the case of t-DeLP and LCC

Pardo Ventura, Pere 19 November 2013 (has links)
Tesi realitzada a l'Institut d'Investigació en Intel.ligència Artificial (IIIIA-CSIC) / In this thesis, we study planning systems based on logics, for two particular cases: Temporal Defeasible Logic Programming t-DeLP and the Logics of Communication and Change LCC. A planning problem consists in building a course of actions, or plan, whose execution leads from a given initial state to some goal state. The motivation for the present studies, from the point of view of Logic, is to obtain systems for practical reasoning (what an agent should do) from given logics oriented to multi-agent systems. From the Artificial Intelligence point of view, the motivation consists in extending the languages and logics underlying the well-known classical or temporal planning systems. This way, a planner can correctly reason about certain concepts (actions, causality, belief, etc.) using an appropriate logic to this end. In practice, the proposed methods permit a planner to aim for goals which can be expressed in the corresponding logical languages. The first part of the thesis contains a study of t-DeLP along these lines. The t-DeLP framework is a non-monotonic temporal logic programming system based on tools from computational argumentation. This logic system aimsto model different types of causal reasoning in a non-monotonic way, but using to this end natural concepts inspired by human reasoning and argumentation. The t-DeLP system is a temporal extension of the DeLP system proposed by García and Simari. In t-DeLP, a knowledge base is given by a set of temporal rules and facts, which combine into arguments (or consistent, minimal derivations) for further derived temporal facts (or conclusions). The language admits two types of rules: strict and defeasible. The former behave similarly to rules in monotonic logics, while derivations or arguments making use of some defeasible rules can be canceled by other existing arguments. To solve the temporal inconsistencies between conflicting arguments, we propose two criteria based on a preference for arguments using more strict facts (more basic information) or less persistence rules. It is shown that the resulting logic programming system satisfies different consistency and closure properties that any logic-argumentation system should obey. In order to define a planning system based on t-DeLP, one can introduce temporal actions as pairs of preconditions and effects. These actions combine with the t-DeLP consequence relation, thus inducing a state transition system. Different search algorithms for centralized planning can be shown to be sound and complete for the class of planning problems definable in t-DeLP. We also study the decentralized case, where a group of planning agents cooperate in order to reach an agreement upon a joint plan for their shared goals. For this, we propose a protocol for argumenative dialogues that defines a plan search algorithm. This algorithm is also shown to be sound and complete, with respect to centralized planning. The second part of the thesis focuses on the Logics of Communication and Change, or LCC. LCC is a family of dynamic epistemic logics proposed by van Benthem et al. Which capture a good deal of the existing dynamic epistemic logics in the literature. The class of LCC modal logics contain a rich class of epistemic operators for multiple agents or groups as well as operators for common knowledge or belief. They also contain dynamic operators for the execution of epistemic actions (communications, observations) or physical actions. The actions of either type can also be modelled with their epistemic effects, that is, how the action will appear to each of the agents. In this thesis, we also extend these logics with product and choice constructors in order to model non-deterministic actions and plans. We propose a simple extension of the axiom system along this line, and show its soundndess and completeness. The proposed planning system based on these logics permit the study of deterministic and non-deterministic planning. In this thesis we show that the corresponding search algorithms based on Breadth First Search are correct and complete for backward planning in a given LCC logic. This is shown for both the deterministic case, and for strong non-deterministic planning. / En aquesta tesi, estudiem algorismes de planificació per a dues lògiques enfocades a sistemes multi-agent. Amb més detall, estudiem problemes de planificació (com arribar a estats objectiu a partir de l'estat inicial i un conjunt d'accions disponibles), els elements dels quals es poden expressar en alguna de les dues lògiques. En la primera part de la tesi, proposem en primer lloc una extensió temporal de la programació lògica rebatible (temporal defeasible logic programming) t-DeLP. Aquest és un sistema de programació lògica no-monotònica basat en tècniques d'argumentació i orientat al raonament sobre les accions, i especialment dels seus efectes indirectes. En el llenguatge d'aquesta lògica, hom pot descriure accions temporals de l'estil de sistemes de planificació, i definir al seu temps un sistema de transicions d'estats. Finalment, això permet definir un sistema de planificació basat en aquesta lògica que combina accions i derivacions lògiques. Les contribucions principals al respecte són: l'estudi de les propietats argumentatives del sistema lògic, i de la correcció i completesa d'algorismes basats en Breadth First Search de cerca en l'espai de plans. En la segona part de la tesi, estudiem sistemes de planificació definits sobre una família de lògiques dinàmiques epistèmiques, conegudes com a Logics of Communication and Change. Aquestes lògiques permeten l'estudi formal de les creences de diversos agents, així com dels efectes epistemics i físics de diferents tipus d'accions. Entre aquestes, podem incloure diferents accions comunicatives (públiques, privades), observacions i les accions físiques habituals en planning. L'estudi del sistema de planificació definit per aquestes lògiques és dut a terme mitjançant algorismes de cerca basats en breadth first search. Les contribucions principals són l'extensió d'aquestes lògiques amb accions no-deterministes i composició d'accions, i la demostració de la correcció
289

Apriority and Colour Inclusion

Reining, Stefan 20 June 2014 (has links)
My central aim in this dissertation is to propose a new version of local scepticism regarding the a priori, namely, a version of scepticism regarding the apriority of (knowledge of) truths about certain relations between colours. The kind of relation in question is, for instance, expressed by sentences like ‘All ultramarine things are blue’ and ‘Nothing is both red all over and green all over’ – sentences that have, among defenders of the a priori, commonly been regarded as expressing paradigm examples of a priori truths. In the course of my argumentation for this kind of local scepticism regarding the a priori, I employ a relatively permissive notion of linguistic understanding (inspired by Timothy Williamson’s recent work on the a priori), according to which it is possible to obtain the relevant kind of understanding of colour terms in a certain non-standard way. The relatively permissive notion of linguistic understanding in question is, in turn, based on considerations in favour of a relatively coarse-grained conception of the primary objects of truth. Furthermore, my argumentation for the kind of local scepticism in question is based on considerations in favour of a certain conception of evidentiality, according to which a single experience-token can play both an enabling and an evidential role in the same instance of knowledge, and according to which some of the experience involved in alleged instances of a priori knowledge of the relations among colours in question plays this kind of double-role. Finally, I consider certain empirical phenomena apparently threatening the possibility of coming to understand colour terms in the non-standard way in question, and I argue that the threat posed by these phenomena is more widespread than hitherto acknowledged, and that all available ways of accommodating these phenomena are compatible with my local scepticism regarding the a priori. / Mi objetivo central en esta tesis es proponer una nueva versión de escepticismo local con respecto al a priori, es decir, una versión de escepticismo con respecto a la aprioridad (del conocimiento de) las verdades sobre ciertas relaciones entre colores. El tipo de relación en cuestión queda, por ejemplo, expresado en oraciones como 'Todas las cosas ultramarinas son azules' y 'Nada es verde y rojo en todas partes' – oraciones que, entre los defensores del a priori, han sido consideradas comúnmente como ejemplos paradigmáticos de verdades a priori. En el curso de mi argumentación, utilizo una noción relativamente permisiva de comprensión lingüística (inspirado en el trabajo reciente de Timothy Williamson sobre el a priori), según la cual es posible obtener comprensión lingüística de términos de color de una cierta manera no estándar. La noción de comprensión lingüística en juego está, a su vez, basada en consideraciones a favor de una concepción de grano relativamente grueso acerca de los objetos primarios de la verdad. Además, mi argumentación se basa en consideraciones a favor de una cierta concepción de evidencialidad, según la cual una experiencia puede jugar tanto un papel comprensión-produciendo como un papel probatorio en la misma instancia de conocimiento y según la cual algunas de las experiencias involucradas en presuntos casos de conocimiento a priori de las relaciones entre colores en juego tienen este tipo de doble función. Finalmente, examino ciertos fenómenos empíricos que al parecer amenazan la posibilidad de llegar a entender a los términos de color en el modo no estándar propuesto, y sostengo que la amenaza planteada por estos fenómenos está más extendida que lo que ha sido reconocido hasta ahora, y que todas las formas disponibles de acomodar estos fenómenos son compatibles con mi escepticismo local con respecto al a priori.
290

A influência dos polimorfismos do gene MDR1 na resposta virológica e imunológica no tratamento com Efavirenz durante os seis primeiros meses em pacientes HIV positivos

Renner, Jane Dagmar Pollo January 2010 (has links)
Made available in DSpace on 2013-08-07T18:42:00Z (GMT). No. of bitstreams: 1 000427653-Texto+Completo-0.pdf: 2414896 bytes, checksum: d0dff31a4951859f81e62225da52e018 (MD5) Previous issue date: 2010 / Drug transporters are increasingly recognized to be important on drug disposition and therapeutic response. P-glycoprotein, encoded by the human MDR1 (ABCB1) gene, is of particular clinical relevance in that this transporter has broad substrate specificity, including a variety of structurally divergent drugs in clinical use today. Efavirenz is a substrate for P-glycoprotein and is metabolized by cytochrome P-450 (CYP) 2B6. In this prospective study, we investigated the influence of the MDR1 genotype polymorphisms (1236C>T, 2677G>T, 3435C>T) in the virological and immunological response to treatment of naïve HIV-infected patients. MDR1 genotype was analyzed in 81 patients attending the Municipal Center for Serology Assistance (CEMAS) in Santa Cruz do Sul, RS, Brazil) who started antiretroviral therapy between 2009 and 2010. Data were obtained at baseline and week 12 and 24 post therapy initiation. MDR1 genotypes were determined by means of polymerase chain reaction followed by analysis of restriction fragment length polymorphism (PCRRFLP). During the first weeks of antiretroviral therapy, the pattern of decrease in viral load was similar for all patients after 12 and 24 weeks of treatment with efavirenz. The reduction in viral load at 12 and 24 weeks was not associated with the genotypes of the polymorphisms 1236C> T, 2677G> T and 3435C> T MDR1 gene. The pattern of increased CD4 + T cells was similar for all patients after 12 and 24 weeks of treatment with efavirenz. The increase in the number of CD4 + T cells was significantly associated with allele 3435T, and are higher in homozygous 3435TT, intermediate in 3435CT and lower in 3435CC however, was not associated with the genotypes of the polymorphisms 1236C> T and 2677G> T MDR1 gene. Individual response to antiretroviral treatment is a complex phenomenon that is influenced by a large number of biological variables. Further studies on the role of polymorphisms of MDR1 transporter and enzymes involved in drug metabolism are needed to elucidate the role of pharmacogenetic effects in HIV therapy. / Os transportadores de drogas são cada vez mais reconhecidos como importantes na disposição das drogas e na resposta terapêutica. A P-glicoproteína é um transportador, codificado pelo gene humano MDR1 (ABCB1), de grande relevância clínica, pois apresenta ampla especificidade de substrato, incluindo uma variedade de drogas com diferentes estruturas atualmente em uso clínico. Efavirenz é substrato para a glicoproteína-P e é metabolizado pelo Citocromo P- 450 (CYP) 2B6. No presente estudo, foi investigada, de forma prospectiva, a influência do genótipo para os diferentes polimorfismos do MDR1 (1236C>T, 2677G>T, 3435C>T) sobre a resposta imunológica e virológica ao tratamento de pacientes infectados pelo HIV, sem tratamento prévio. O genótipo MDR1 foi analisado em 81 pacientes do Centro Municipal de Atendimento à Sorologia (CEMAS), em Santa Cruz do Sul (RS, Brasil), que iniciaram terapia antiretroviral entre 2009 e 2010. Os dados foram obtidos ao início do tratamento e nas semanas 12 e 24 após o início da terapia. Os genótipos MDR1 de cada indivíduo foram determinados com a utilização de reação em cadeia da polimerase, seguida de análise dos fragmentos de restrição (PCR-RFLP). Durante as primeiras semanas de terapia antiretroviral, o padrão de diminuição da carga viral foi similar para todos os pacientes após 12 e 24 semanas de tratamento com Efavirenz. A redução da carga viral em 12 e 24 semanas não se mostrou associada aos genótipos dos polimorfismos 1236C>T, 2677G>T e 3435C>T do gene MDR1. O padrão do aumento das células T CD4+ foi similar para todos os pacientes após 12 e 24 semanas de tratamento com Efavirenz. O aumento no número de células T CD4+ foi significativamente associado à presença do alelo 3435T, sendo mais elevado nos homozigotos 3435TT, intermediário em 3435CT e menos elevado em 3435CC em contrapartida, não se mostrou associado aos genótipos dos polimorfismos 1236C>T e 2677G>T do gene MDR1. A resposta individual ao tratamento antiretroviral é um fenômeno complexo que é influenciado por um grande número de variáveis biológicas. Novos estudos sobre o papel dos polimorfismos do transportador MDR1 e enzimas envolvidas no metabolismo de drogas são necessários para elucidar o papel dos efeitos farmacogenéticos na terapêutica para o HIV.

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