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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.
121

A parábola do homem estagnado em Nenhum olhar, de José Luís Peixoto / The parable of the stagnant man in Nenhum olhar by José Luís Peixoto

Costa, Cibele Lopresti 20 April 2016 (has links)
Este trabalho tem o objetivo de registrar o processo de uma leitura de Nenhum olhar, de José Luís Peixoto, a partir do reconhecimento de um conjunto de enigmas que o romance elabora, estendendo a negatividade do título às várias camadas do texto narrativo. O método escolhido para a análise baseia-se na hermenêutica de Paul Ricoeur, que destaca a relação tensionada entre o texto literário (como conjunto de enigmas) e o leitor (com sua bagagem decifrativa). A análise textual realizada proporcionou a observação dos mecanismos de enunciação que dotam o texto de um particular hermetismo. Através desses mecanismos, José Luís Peixoto apresenta uma abordagem bastante complexificadora do homem simples do Alentejo. Por meio deles, foi possível identificar aproximações entre o texto peixoteano e as parábolas bíblicas. E na universalidade que essa abordagem é capaz de atingir, Nenhum olhar é aqui lido como parábola contemporânea do homem estagnado. / This work is focused on the reading process of Nenhum Olhar, by José Luís Peixoto, given the observation of a series of enigmas built by the novel, expanding the negativity of its title to several layers of the narrative. The method chosen is based on Paul Ricoeur`s hermeneutics, which points to a tensioned relationship between the literary text (as a series of enigmas) and the reader (with their background to decipher). The text analysis made it possible the observation of mechanisms of enunciation, which made the text especially hermetic. Through these mechanisms, José Luís Peixoto gives us a very complexifying approach of the humble man from the Alentejo. Thereby it was possibe to identify connections between Peixoto`s text and parables from the Bible. Thus, because of the universal character that this approach may reach, Nenhum Olhar can here be interpreted as a contemporary parable of the stagnant man.
122

A Controlled Comparison of Errorless and Errorful Learning in Individuals with Moderate-to-Severe Traumatic Brain Injury

Fair, Joseph Edward 01 June 2015 (has links)
The prevalence and sequelae of moderate-to-severe (M/S) traumatic brain injury (TBI) are significant and pervasive problems, and effective rehabilitation techniques are key. Errorless learning is regarded as a useful tool for memory impairments; however, the efficacy of errorless learning in a M/S TBI population is unclear. The primary goal (aim 1) of this study was to evaluate the efficacy of a single session of errorless vs. errorful learning in a group of M/S TBI survivors and matched controls. A secondary goal (aim 2) was to investigate the neural time course of errorless learning in participants with M/S TBI by analyzing the error-related negativity (ERN) component of the scalp-recorded event-related potential (ERP). The ERN is an electrophysiological measure of error processing that is disrupted in M/S TBI survivors. Measures of neuropsychological performance, self- and informant-report of executive functioning, and affect further informed both study aims. Data from 28 M/S TBI survivors (9 female) and 28 controls (9 female) were analyzed for aim 1, with data from 19 M/S TBI survivors (6 female) and 20 controls (8 female) analyzed for aim 2. There were significant differences between the TBI and control groups with regard to executive, mood, and neuropsychological functioning. Results from aim 1 indicated that TBI participants were slower across learning conditions, while both groups had significantly faster reaction times in the errorless condition. Regarding accuracy, there was not a statistically significant main effect of learning condition (p = .07), group (p = .06), or Group x Condition x Accuracy interaction (p = .33). Indices of memory and executive functioning, and group (TBI, Control) used in regressions predicted accuracy in both learning conditions (ps < .01). The memory composite was a significant independent predictor of errorless accuracy. Results from aim 2 indicated a reliable ERN was present across conditions, although there were no main effects of Condition, Group, or Group x Condition interactions on ERN amplitude or latency (ps > .22). ERN latency was not predictive of accuracy for either condition (ps > .08). Group was a significant independent predictor of accuracy in the errorless condition (p = .05), but not the errorful condition (p = .45). Findings indicate that memory functioning was a better predictor of accuracy than executive functioning or group membership. This suggests that the errorless learning benefit may be specific to memory functioning, rather than other cognitive variables. This conclusion aligns with research reporting that benefits of errorless learning depend upon the severity of memory impairments. Results from ERN analyses are only partially supported by previous research, and further work is needed to clarify the role of neural representations of errorless learning in M/S TBI.
123

Separating Post-perceptual Processes From Auditory Awareness : An Electrophysiological Study With a No-response Task

Fjordstig, Andréas January 2019 (has links)
Two theories of consciousness have different ideas about when consciousness happens and what neural processes enable conscious experience. The recurrent processing theory supports an early onset of consciousness caused by recurring loops of information between sensory areas. Contrary to this belief, the global workspace theory claims that consciousness appears later, through global recurrent loops of information between sensory and higher order brain areas such as the visual cortex and frontoparietal areas. Electrophysiological studies have found an event-related negativity arising in primary visual areas around 200 ms that correlates to awareness. This activity suits the predictions of an early onset of consciousness made by the recurrent processing theory. It is followed by a later positive amplitude appearing around 400 ms. This activity is in line with predictions made by the global workspace theory. The current study transition from visual to auditory awareness research in order to find the neural correlates of consciousness in audition. A sound detection task with tones calibrated to each participants threshold value was used in the experiment and two electrophysiological measurements of auditory awareness were found. An auditory awareness negativity that appears around 200 ms after stimulus onset and a late positivity appearing around 400 ms. Researchers disagree about if these event-related potentials correlate with awareness or unrelated cognitive mechanisms. In order to solve this problem, the current experiment was devised to test if they were affected by response conditions. A no-response paradigm with reversed response conditions was used to separate pre- and post-conscious mechanisms from the auditory awareness negativity and the late positivity. Results showed that auditory awareness negativity was independent of response condition and thus free from post-perceptual processes. The late positivity amplitude seems to be dependent on response condition but the result was inconclusive.
124

Signatures of non-classicality in optomechanical systems

Mari, Andrea January 2012 (has links)
This thesis contains several theoretical studies on optomechanical systems, i.e. physical devices where mechanical degrees of freedom are coupled with optical cavity modes. This optomechanical interaction, mediated by radiation pressure, can be exploited for cooling and controlling mechanical resonators in a quantum regime. The goal of this thesis is to propose several new ideas for preparing meso- scopic mechanical systems (of the order of 10^15 atoms) into highly non-classical states. In particular we have shown new methods for preparing optomechani-cal pure states, squeezed states and entangled states. At the same time, proce-dures for experimentally detecting these quantum effects have been proposed. In particular, a quantitative measure of non classicality has been defined in terms of the negativity of phase space quasi-distributions. An operational al- gorithm for experimentally estimating the non-classicality of quantum states has been proposed and successfully applied in a quantum optics experiment. The research has been performed with relatively advanced mathematical tools related to differential equations with periodic coefficients, classical and quantum Bochner’s theorems and semidefinite programming. Nevertheless the physics of the problems and the experimental feasibility of the results have been the main priorities. / Die vorliegende Arbeit besteht aus verschiedenen theoretischen Untersuchungen von optomechanischen Systemen, das heißt physikalische Bauteile bei denen mechanische Freiheitsgrade mit Lichtmoden in optischen Kavitäten gekoppelt sind. Diese optimechanischen Wechselwirkungen, die über den Strahlungsdruck vermittelt werden, lassen sich zur Kühlung und Kontrolle von mechanischen Resonatoren im Quantenregime verwenden. Das Ziel dieser Arbeit ist es, verschiedene neue Ideen für Methoden vorzuschlagen, mit denen sich mesoskopische mechanische Systeme (bestehend aus etwa 10^15 Atomen) in sehr nicht-klassischen Zuständen präparieren lassen. Außerdem werden Techniken beschrieben, mit denen sich diese Quateneffekte experimentell beobachten lassen. Insbesondere wird ein quantitatives Maß für Nichtklassizität auf der Basis von Quasiwahrscheinlichkeitsverteilungen im Phasenraum definiert und ein operationeller Algorithmus zu dessen experimenteller Beschrieben, der bereits erfolgreich in einem quantenoptischen Experiment eingesetzt wurde.
125

Vocal and instrumental musicians: Electrophysiologic and psychoacoustic analysis of pitch discrimination and production

Nikjeh, Dee Adams 01 June 2006 (has links)
Neurological evidence indicates that instrumental musicians experience changes in the auditory system following skill acquisition and sensory training; yet, little is known about auditory neural plasticity in formally trained vocal musicians. Furthermore, auditory pitch discrimination and laryngeal control are recognized as essential skills for vocal musicians; however, the relationship between physiological variables, perceptual abilities, and vocal production is unclear. Electrophysiologic and psychoacoustic measures were used to examine pitch production accuracy as well as pre-attentive and active pitch discrimination between nonmusicians and two classes of musicians. Participants included 40 formally trained musicians (19 vocalists/21 instrumentalists) and 21 nonmusician controls. All were right-handed young adult females with normal hearing. Stimuli were harmonic tone complexes approximating the physical characteristics of piano tones and represented the mid-frequency range of the untrained female vocal register extending from C4 to G4 (F0 = 261.63-392 Hz). Vocal pitch recordings were spectrally analyzed to determine pitch production accuracy. Difference limens for frequency (DLFs) were obtained by an adaptive psychophysical paradigm. Pre-attentive auditory discrimination was assessed by auditory evoked potentials (AEPs), including the mismatch negativity (MMN). A standard tone (G4 = 392 Hz) and three deviants differing in frequency (1.5%, 3%, and 6% below) were presented in a multi-deviant paradigm. All musicians demonstrated superior pitch perception and vocal production compared to nonmusicians. Pitch perception and production accuracy did not significantly differ between vocalists and instrumentalists; however, pitch production accuracy was most consistent within the vocalist group. Music training appears to facilitate both auditory perception and vocal production regardless of music specialty. Pitch perception and production were correlated skills only for instrumental musicians. Vocalists demonstrated minimal variability for both skills so that perception and production were not correlated. These two skills may be independent abilities between which a relationship develops with training. AEP analysis revealed an influence of musical expertise on neural responses as early as 50 ms after onset of musically relevant stimuli. MMN responses indicate that vocal musicians as well as instrumental musicians have superior sensory memory representations for acoustic parameters of harmonic stimuli and imply that auditory neural sensitivity is developed by intense music training.
126

Disenchanted engagement : the philosophy and political praxis of Massimo Cacciari

Lavenda, Daniel January 2015 (has links)
Several commentators have argued that the focus within political theory in recent decades on abstraction rather than 'reality' has left it with has nothing to say to political actors. On these grounds, some have even expressed concern regarding the discipline's future. As a reply to these concerns, I introduce in this thesis the scholarship and political career of the Italian philosopher Massimo Cacciari. Cacciari shares many goals with Anglophone political theorists, but neither his scholarship nor his practice have engaged in the kind of intellectual abstraction which they now find so troubling. Drawing from Cacciari's philosophy, political career, and interventions as a public intellectual, I show how his understanding of real-world conflicts and contradictions begins with a commitment to what I call his 'geophilosophy of the archipelago', which regards the foundations of human knowledge to be irreducibly plural. A commitment to irreducibly plural foundations means that philosophers and political actors must discard what Cacciari views as 'enchantment' with the possibility of ultimate or absolute resolution of all political discord. In return, however, he argues that hopeful political engagement is still possible, because political actors remain able to cope in material and semiotic terms with the complex realities they face. I suggest that serious consideration of Cacciari's example of recognising irreducible plurality, coupled with a disenchanted engagement with both the material and the semiotic dimensions of political life, offers a compelling alternative orientation to the world that may suggest new ways forward in political theory.
127

Œuvre(s) du pluriel : vers une esthétique du dispersé / Work(s) in the plural : towards an aesthetics of dispersion

Lascault, Michel 30 September 2017 (has links)
La pluridisciplinarité artistique contemporaine, qui remonte à l’humanisme et au romantisme, est-elle encore liée à un désir de connaissance et de totalité, ou s’inscrit-elle dans un spectre de fragmentation ? Les défaillances reconnues du savoir, du sujet et de l’œuvre forment une résistance à la puissance des technostructures. La sphère de l’art, détachée de la division du travail artistique, s’inscrit dans une négativité non dialectique. Par la sape méthodique des référents et des maîtrises, l’œuvre s’ouvre au désordre et au manque. Poursuivant simultanément plusieurs démarches distinctes dans les arts visuels, la musique et l’écriture, passant de l’art populaire à l’art intellectualisé, étant autant témoin qu’acteur de mon travail, je propose une approche de l’art qui se définit plus par l’errance et la pluralité que par un projet unitaire. La position mineure et dispersée se ressource dans une poïétique prolifique : simultanéité divergente, transposition négative, hétérogénéité, confusion des temps, présence du vide et du fantomatique… / Is artistic pluridisciplinarity, which goes back to Humanism and Romanticism, still connected to a desire for knowledge and for holistic apprehension, or does it reveal the prospect of fragmentation? The known shortcomings of knowledge, of the subject, and of the work of art resist the power of techno-structures. Once the artistic sphere gets disconnected from the division of artistic labor, it is amenable to a non-dialectical negativity. As the work of art methodically subverts referents, mastery and know-hows, it becomes accessible to loss and disorder. Being as much the witness as the agent of the work I produce, I propose an approach to art conceived as wandering and plural—an approach based on various forms of practice in visual arts, music, and writing, which shift from popular to intellectual art. This artistic stance, minor and scattered, draws its strength from a prolific poietics: divergent simultaneity, negative transposition, heterogeneity, confusion of temporalities, void, and haunting presences…
128

Syngas production by integrating thermal conversion processes in an existing biorefinery

Åberg, Katarina January 2014 (has links)
The use of carbon from fossil-based resources result in changes in the earth’s climate due to emissions of greenhouse gases. Biomass is the only renewable source of carbon that may be converted to transportation fuels and chemicals, markets now fully dominated by traditional oil supply. The biorefinery concept for upgrading and refinement of biomass feedstocks to value-added end-products has the potential to mitigate greenhouse gas emissions and replace fossil products. Most biorefineries use biochemical conversion processes and may have by-product streams suitable as feedstocks for thermal conversion and production of syngas. Further synthesis to value-added products from the syngas could increase the product output from the biorefinery. The application of thermal conversion processes integrated into an existing biorefinery concept has been evaluated in this licentiate thesis work. Two by-product streams; hydrolysis (lignin) residue from an ethanol plant and biogas from wastewater treatment, have been investigated as gasification/reforming feedstocks. Also, the pre-treatment method torrefaction has been evaluated for improved gasification fuel characteristics and integration aspects. A new process and system concept (Bio2Fuels) with potential carbon negative benefits has been suggested and evaluated as an alternative route for syngas production by separating biomass into a hydrogen rich gas and a carbon rich char product. The evaluation demonstrated that hydrolysis residue proved a suitable feedstock for gasification with respect to syngas composition. Biogas can be further reformed to syngas by combined biomass gasification and methane reforming, with promising results on CH4 conversion rate and increased H2/CO ratio at temperatures ≥1000°C. The pre-treatment method torrefaction was demonstrated to improve fuel qualities and may thus significantly facilitate entrained flow gasification of biomass residue streams. Also, integration of a torrefaction plant at a biorefinery site could make use of excess heat for drying the raw material before torrefaction. The Bio2Fuels concept was evaluated and found feasible for further studies. The application of thermal conversion processes into an existing biorefinery, making use of by-products and biomass residues as feedstocks, has significant potential for energy integration, increased product output as well as for climate change mitigation.
129

A parábola do homem estagnado em Nenhum olhar, de José Luís Peixoto / The parable of the stagnant man in Nenhum olhar by José Luís Peixoto

Cibele Lopresti Costa 20 April 2016 (has links)
Este trabalho tem o objetivo de registrar o processo de uma leitura de Nenhum olhar, de José Luís Peixoto, a partir do reconhecimento de um conjunto de enigmas que o romance elabora, estendendo a negatividade do título às várias camadas do texto narrativo. O método escolhido para a análise baseia-se na hermenêutica de Paul Ricoeur, que destaca a relação tensionada entre o texto literário (como conjunto de enigmas) e o leitor (com sua bagagem decifrativa). A análise textual realizada proporcionou a observação dos mecanismos de enunciação que dotam o texto de um particular hermetismo. Através desses mecanismos, José Luís Peixoto apresenta uma abordagem bastante complexificadora do homem simples do Alentejo. Por meio deles, foi possível identificar aproximações entre o texto peixoteano e as parábolas bíblicas. E na universalidade que essa abordagem é capaz de atingir, Nenhum olhar é aqui lido como parábola contemporânea do homem estagnado. / This work is focused on the reading process of Nenhum Olhar, by José Luís Peixoto, given the observation of a series of enigmas built by the novel, expanding the negativity of its title to several layers of the narrative. The method chosen is based on Paul Ricoeur`s hermeneutics, which points to a tensioned relationship between the literary text (as a series of enigmas) and the reader (with their background to decipher). The text analysis made it possible the observation of mechanisms of enunciation, which made the text especially hermetic. Through these mechanisms, José Luís Peixoto gives us a very complexifying approach of the humble man from the Alentejo. Thereby it was possibe to identify connections between Peixoto`s text and parables from the Bible. Thus, because of the universal character that this approach may reach, Nenhum Olhar can here be interpreted as a contemporary parable of the stagnant man.
130

Desejo e negatividade na filosofia de Merleau-Ponty / Desire and negativity in the Merleau-Ponty\"s philosophy

Vitor Hugo de Oliveira 05 April 2012 (has links)
O presente trabalho visa discutir, a partir das últimas obras de Merleau-Ponty, a articulação entre sua noção de desejo e o conceito de negativo. A pesquisa buscou primeiramente traçar o que o filósofo denomina de arqueologia do contato primordial do corpo com o mundo, buscando a camada pré-objetiva de abertura perceptiva a ele, a sentidos que não foram constituídos pelo sujeito, que o ultrapassam e lhe determinam vetores de sentido. Os temas arqueológicos enfocam as noções de instituição e passividade, a relação da corporeidade humana com a animalidade, e o esquema corporal como abertura estesiológica e libidinal ao mundo, questões que nos abrem a dimensão transtemporal e transespacial do corpo, que arrasta consigo um passado que retoma e antecipa as possibilidades do porvir. A partir desses tópicos, compreende-se que o desejo é busca de ser o dentro do fora e o fora do dentro no sistema de trocas do corpo com o mundo. É nesse sentido que se podem ressaltar algumas noções psicanalíticas, pois elas permitem apreender essa topologia arqueológica do contato, as estruturações de sentido que nos permitem significar o mundo, e que não são de autoria de uma consciência constituinte. Por outro lado, o trabalho discutiu a ideia de negativo na obra do filósofo, a partir de seu diálogo com Sartre, tratando-o a partir da noção de invisível e de imaginário, que representam o avesso e a espessura do ser, como um oco eficaz que se manifesta à percepção. Partindo dessas construções merleau-pontyanas, discute-se a relação desejo-negatividade, a partir da crítica que o filósofo faz a Sartre e à própria Psicanálise, que interpretam o desejo como, respectivamente, estando destinado ao fracasso, e de ser em sua essência falta por um objeto para sempre perdido. Focou-se então na compreensão de uma negatividade natural enquanto latência, espessura do sensível e do corpo, que é condição mesma da percepção e que delineia uma relação de desequilíbrio entre o sujeito e a inesgotabilidade do mundo. Concebendo a Natureza como esse tecido carnal que provoca a carne do corpo, e o corpo senciente enquanto dobra do sensível sobre si mesmo, como retomada e explicitação privilegiada dessa potência interrogativa da vida, pode-se ver que o desejo é inerente ao sentir, contato à distância, espessura denominada pela noção de negatividade natural. / The following thesis aims to discuss, from the latest works by Merleau-Ponty, the balance between the notion of desire and the concept of negative. The research looked for, at first, trace what the philosopher called archeology of the primordial contact of the body to the world, seeking the pre-objective layer of the perceptual opening to him, to senses wich were not composed by the subject, that exceeded himself and gave him arrays of sense. The archeologicals themes focus the notions of institution and passivity, the relation between human corporeality and animality, and the body scheme as esthesiologic and libidinal opening to the world, issues that bring us the transtemporal and trans-spatial dimensioning of the body, that draws a past which comes back and anticipates the possibilities of the future. Based on these topics, we understand that the desire is the seeking of being the inside of outside and the outside of the inside in the system of trading between the body and the world. In this sense we can highlight some psychoanalytic concepts, as they allow us to capture this archaeological topology of the contact, the structuring of the senses which allow us mean the world, and do not belong to a constitutive conciousness. On the other hand, the thesis discussed the idea of the negative in the work of the philosopher, from his dialogue with Sartre, dealing it from the notion of invisible and of imaginary, that represent the inside out and the thickness of the being, as a efficacious hollow that manifest itself to the perception. From these merleau-pontyans concepts, it is discussed the relation between desire and negativity, from the critical note the philosopher have made on Sartre and on his own Psychoanalysis, which interpreted the desire as, respectively, being intended to failure, and of being in its essence, the lack of an object forever lost. So, focused in the comprehension of a natural negativity while latency, thickness of the sensible and of the body, which is the same as perception and that outlines a imbalanced relationship between the subject and the inexhaustibility of the world. Conceiving the Nature as this flesh tissue that provokes the flesh of the body, and the body being sentient while fold from sensible over itself, as retaking and privileged explanation of this interrogative potency of the life, it is possible to realize that the desire is inherent to the feel, distance contact, through thickness called by the notion of natural nagativity.

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