This thesis is concerned with the challenge truth-value gaps pose to the principle of bivalence. The central question addressed is: are truth-value gaps counterexamples to bivalence and is the supposition of counterexamples coherent? My aim is to examine putative cases of truth-value gaps against an argument by Timothy Williamson, which shows that the supposition of counterexamples to bivalence is contradictory. The upshot of his argument is that either problematic utterances say nothing, or they cannot be neither true nor false. I start by identifying truth-bearers: an utterance, for instance, is a truth-bearer if it says that something is the case. Truth-bearers are evaluable items, with truth- and falsity-conditions statable in corresponding instances of schemas for truth and falsehood. A genuine case of a truth-value gap should be an utterance that is neither true nor false but says something to be the case. But it is inconsistent to accept the schemas for truth and falsehood and the existence of genuine cases of truth-value gaps. Secondly, I expound Williamson’s argument, which explores this inconsistency, and I identify two kinds of strategy to disarm his argument: those that preserve the schemas for truth and falsehood, and those that do not. Neither strategy is found to be persuasive. Thirdly, I argue that cases of reference failure causing truth-value gaps illustrate the upshot of Williamson’s argument. Fourthly, I examine Scott Soames’s account of liar sentences as counterexamples to bivalence. Soames adopts a strategy of the first kind to avoid contradictions. I argue that his solution allows some contradictions to be true, and that he fails to show that liar sentences are truth-bearers. Finally, I examine Charles Travis’s case for isostheneia: an equal balancing of reasons to evaluate a statement as true or as false, in which case a statement is neither. Travis avoids contradictions by adopting a strategy of the second kind. I argue that the schemas for truth and falsehood are immune to Travis’s objections, and that isostheneia fails to identify evaluable items. The cases examined confirm that utterances that are neither true nor false say nothing. My claim is thus that truth-value gaps are not counterexamples to bivalence.

Julgo que a recusa do determinismo causal em Metaphysica E3/K8 mediante a tese de que nem todo evento se deve a causas necessitantes de seus efeitos acarreta (mediante a concepção em Categoriae 5 segundo a qual a proposição é verdadeira ou falsa conforme em um tempo se dê ou não se dê a correspondência entre a proposição e um estado de coisas situado nesse mesmo tempo) a recusa do determinismo lógico em De Interpretatione 9 mediante a tese de que proposições a respeito de eventos futuros contingentes não são nem verdadeiras nem falsas ex ante facto e, por conseguinte, nem toda proposição é em qualquer tempo verdadeira ou falsa. Julgo, ademais, que o comprometimento com a tese de que nem todo evento se deve a causas necessitantes de seus efeitos decorre de o filósofo comprometerse com a noção de deliberação. Acompanha o presente trabalho a tradução comentada de De Interpretatione 9. / Aristotles refusal of causal determinism in Metaphysics E3/K8 by means of the thesis that not every event is necessitated entails (given the conception put forward in Categories 5 that a proposition is either true or false according to its either corresponding or not corresponding at a given time to a state of affairs at that same given time) his refusal of logical determinism in De Interpretatione 9 by means of the thesis that propositions about future contingent events are neither true nor false ex ante facto but become either true or false afterwards. Aristotles commitment to non-necessitated events stems, it is argued, from his commitment to the notion of deliberation. This work includes a translation, with commentary, of De Interpretatione 9.

Julgo que a recusa do determinismo causal em Metaphysica E3/K8 mediante a tese de que nem todo evento se deve a causas necessitantes de seus efeitos acarreta (mediante a concepção em Categoriae 5 segundo a qual a proposição é verdadeira ou falsa conforme em um tempo se dê ou não se dê a correspondência entre a proposição e um estado de coisas situado nesse mesmo tempo) a recusa do determinismo lógico em De Interpretatione 9 mediante a tese de que proposições a respeito de eventos futuros contingentes não são nem verdadeiras nem falsas ex ante facto e, por conseguinte, nem toda proposição é em qualquer tempo verdadeira ou falsa. Julgo, ademais, que o comprometimento com a tese de que nem todo evento se deve a causas necessitantes de seus efeitos decorre de o filósofo comprometerse com a noção de deliberação. Acompanha o presente trabalho a tradução comentada de De Interpretatione 9. / Aristotles refusal of causal determinism in Metaphysics E3/K8 by means of the thesis that not every event is necessitated entails (given the conception put forward in Categories 5 that a proposition is either true or false according to its either corresponding or not corresponding at a given time to a state of affairs at that same given time) his refusal of logical determinism in De Interpretatione 9 by means of the thesis that propositions about future contingent events are neither true nor false ex ante facto but become either true or false afterwards. Aristotles commitment to non-necessitated events stems, it is argued, from his commitment to the notion of deliberation. This work includes a translation, with commentary, of De Interpretatione 9.

Le protéasome et l’immunoprotéasome possèdent trois activités catalytiques différentes et dégradent une grande variété de protéines. Leur rôle central dans de nombreux processus tels que le contrôle du cycle cellulaire et circadien, la régulation des voies de défense contre le stress font d’eux des cibles majeures dans le processus de vieillissement et dans le traitement des cancers. Aussi, le lien établi entre l'horloge circadienne et les défenses anti-oxydantes suggère que l'homéostasie redox des protéines et leur élimination par le protéasome soient modulées par l'horloge circadienne. L’étude d’inhibiteurs bivalents et non covalents du protéasome a montré que de cibler deux sites actifs à la fois permet d’augmenter l’efficacité et la sélectivité. Nous avons également effectué l'évaluation de la pénétration cellulaire de ces molécules à l’aide de sondes fluorescentes non covalentes conçues par le laboratoire. Nous avons montré que les activités peptidases du protéasome présentent une rythmicité circadienne en antiphase avec le taux de protéines carbonylées. L'expression circadienne de NRF2 et de l'activateur PA28 expliquerait cette stimulation de l'activité du protéasome. De plus, contrairement aux fibroblastes jeunes, aucune modulation circadienne du protéasome et du niveau de ROS n’a été mise en évidence dans les fibroblastes sénescents. Des résultats préliminaires de nos inhibiteurs sur le modèle cellulaire HEK293 synchronisé montrent que leur efficacité varie en fonction du rythme circadien et qu’elle est meilleure lorsque les activités du protéasome sont minimales. Ces résultats suggèrent que le protéasome puisse être une nouvelle cible pour la chronothérapie. / Proteasome and immunoproteasome have three different catalytic activities, and degrade a wide variety of proteins. Their central role in many pathways such as control of cellular and circadian cycles, regulation of the defense pathways against stress make them major targets in the aging process and in the treatment of cancer. Also, the link between the circadian clock and antioxidant defenses suggests that the redox homeostasis of proteins and their removal by the proteasome could be modulated by the circadian clock.Studying non-covalent and bivalent proteasome inhibitors showed that targeting two active sites at the same time results in increasing their efficiency and selectivity. We also carried out the evaluation of the cell penetration of these molecules using non-covalent fluorescent probes designed in the laboratory.We have shown that the peptidase activities of proteasome exhibit circadian rhythmicity in antiphase with protein carbonyl intracellular content. The circadian expression of NRF2 and PA28 activator can explain this stimulation of proteasome activity. Moreover, in contrast to young fibroblasts, no circadian modulation of the proteasome and the level of ROS have been observed in senescent fibroblasts.Preliminary results obtained with our inhibitors on the synchronized HEK293 cell model suggest that their effectiveness varies depending on the circadian rhythm and they are more efficient when proteasome activities are minimal. These results suggest that the proteasome could be a new target for chronotherapy.

The goal of this thesis is to design a heating system for a building of an elementary school in Polešovice. The thesis is divided into three parts. The first, theoretical, part discusses heat pumps with the main focus on gas absorption heat pumps. The se-cond part addresses the design of the school heating as well as the design of an ecological heat source. The part consisting calculations introduces the calculation of heat losses, the optimal choice of temperature gradient, the design of heating surfaces, the design of heat sources including the design of the bivalent source, the way of hot water preparation, dimensioning, the security equipment and other calculations. The last part deals with the drawing documentation, the technical report and also some economical questions such as return on investment based on measured efficiency of the heat source.

A presente dissertação investiga a interpretação de Tomás de Aquino ao problema dos futuros contingentes, relativo ao capítulo 9 do tratado De Interpretatione, de Aristóteles. O objetivo central é explicar qual a função do termo "determinate" na interpretação de Tomás. Para isso, reconstrói a noção aristotélica de proposição como uma atividade enunciativa, assim como investiga o Livro Gama da Metafísica, o qual defende os princípios de não contradição e terceiro excluído. Nesse percurso, chama a atenção para o fato de que, do ponto de vista da proposição, as formulações sintáticas dos princípios metafísicos são primeiras em relação às semânticas. Com isso, pretende identificar uma distinção entre as condições de sentido de uma proposição e a atribuição de um valor verdade e, através de tal distinção, propõe uma leitura para a solução de Tomás de Aquino ao problema referido. Conclui que a oposição contraditória como exclusiva e exaustiva é uma tese logicamente anterior à caracterização da proposição como bivalente ou determinadamente verdadeira ou falsa. / This dissertation investigates the interpretation of Thomas Aquinas to the problem of future contingents, concerning the chapter 9 of Aristotle's De Interpretatione. The main goal is to explain what is the function of the term "determinate" on Aquinas's interpretation. For that reason, the dissertation intends to reconstruct Aristotle's notion of proposition as an enunciating activity, as well as to investigate the Book Gamma of Metaphysics, which defends the principles of non-contradiction and excluded middle. During that reasoning, it turns the attention to the fact that, from the proposition's point of view, the syntactic formulations of the metaphysical principles are prior to the semantic ones. Thereby, it claims to identify a distinction between the sense conditions of a proposition and the attribution of a truth value and, as a result of that distinction, it proposes a reading of Aquinas's solution to the abovementioned problem. It concludes that the contradictory opposition as excluding and exhausting is a thesis logically prior to the characterization of a proposition as bivalent or determinately true or false.

A presente dissertação investiga a interpretação de Tomás de Aquino ao problema dos futuros contingentes, relativo ao capítulo 9 do tratado De Interpretatione, de Aristóteles. O objetivo central é explicar qual a função do termo "determinate" na interpretação de Tomás. Para isso, reconstrói a noção aristotélica de proposição como uma atividade enunciativa, assim como investiga o Livro Gama da Metafísica, o qual defende os princípios de não contradição e terceiro excluído. Nesse percurso, chama a atenção para o fato de que, do ponto de vista da proposição, as formulações sintáticas dos princípios metafísicos são primeiras em relação às semânticas. Com isso, pretende identificar uma distinção entre as condições de sentido de uma proposição e a atribuição de um valor verdade e, através de tal distinção, propõe uma leitura para a solução de Tomás de Aquino ao problema referido. Conclui que a oposição contraditória como exclusiva e exaustiva é uma tese logicamente anterior à caracterização da proposição como bivalente ou determinadamente verdadeira ou falsa. / This dissertation investigates the interpretation of Thomas Aquinas to the problem of future contingents, concerning the chapter 9 of Aristotle's De Interpretatione. The main goal is to explain what is the function of the term "determinate" on Aquinas's interpretation. For that reason, the dissertation intends to reconstruct Aristotle's notion of proposition as an enunciating activity, as well as to investigate the Book Gamma of Metaphysics, which defends the principles of non-contradiction and excluded middle. During that reasoning, it turns the attention to the fact that, from the proposition's point of view, the syntactic formulations of the metaphysical principles are prior to the semantic ones. Thereby, it claims to identify a distinction between the sense conditions of a proposition and the attribution of a truth value and, as a result of that distinction, it proposes a reading of Aquinas's solution to the abovementioned problem. It concludes that the contradictory opposition as excluding and exhausting is a thesis logically prior to the characterization of a proposition as bivalent or determinately true or false.

A presente dissertação investiga a interpretação de Tomás de Aquino ao problema dos futuros contingentes, relativo ao capítulo 9 do tratado De Interpretatione, de Aristóteles. O objetivo central é explicar qual a função do termo "determinate" na interpretação de Tomás. Para isso, reconstrói a noção aristotélica de proposição como uma atividade enunciativa, assim como investiga o Livro Gama da Metafísica, o qual defende os princípios de não contradição e terceiro excluído. Nesse percurso, chama a atenção para o fato de que, do ponto de vista da proposição, as formulações sintáticas dos princípios metafísicos são primeiras em relação às semânticas. Com isso, pretende identificar uma distinção entre as condições de sentido de uma proposição e a atribuição de um valor verdade e, através de tal distinção, propõe uma leitura para a solução de Tomás de Aquino ao problema referido. Conclui que a oposição contraditória como exclusiva e exaustiva é uma tese logicamente anterior à caracterização da proposição como bivalente ou determinadamente verdadeira ou falsa. / This dissertation investigates the interpretation of Thomas Aquinas to the problem of future contingents, concerning the chapter 9 of Aristotle's De Interpretatione. The main goal is to explain what is the function of the term "determinate" on Aquinas's interpretation. For that reason, the dissertation intends to reconstruct Aristotle's notion of proposition as an enunciating activity, as well as to investigate the Book Gamma of Metaphysics, which defends the principles of non-contradiction and excluded middle. During that reasoning, it turns the attention to the fact that, from the proposition's point of view, the syntactic formulations of the metaphysical principles are prior to the semantic ones. Thereby, it claims to identify a distinction between the sense conditions of a proposition and the attribution of a truth value and, as a result of that distinction, it proposes a reading of Aquinas's solution to the abovementioned problem. It concludes that the contradictory opposition as excluding and exhausting is a thesis logically prior to the characterization of a proposition as bivalent or determinately true or false.