Made available in DSpace on 2014-12-17T15:36:43Z (GMT). No. of bitstreams: 1 FernandoRFS_TESE.pdf: 469950 bytes, checksum: a8f86cc336421fd74e299ebe8f8d1daf (MD5) Previous issue date: 2014-11-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The use and the demand for substances that enhance masculinity, strength and sexual power are not novel. Over the years, this search has assisted the research directions in this area, leading to the discovery of the primary male sex hormone testosterone in 1935. Since then, numerous testosterone analogue compounds were synthesized, which are generically called Anabolic Androgenic Steroids (AAS). The AAS were produced for therapeutic purposes, but an increase in the use of these compounds for other purposes occurred over time. Initially they were used mainly to improve performance in athletes. However, recent studies have shown that the use of AAS by non-athletes with aesthetical purposes have been increasing as well. The abuse of AAS with non-clinical purposes can promote a number of physiological alterations, such as heart, liver, respiratory and psychological problems such as changes in mood, levels of anxiety and aggression. Exposure to supraphysiological doses of AAS is associated with behavioral changes, however, little is known about the effects of AAS on cognitive functions. In this work, we aimed to mimic the AAS abuse in humans with intramuscular administration of a supraphysiological dose of testosterone propionate (TP) in rats. We investigated the effects of this treatment on different aspects of cognitive function, specifically learning, memory and anxiety. Adult male Wistar rats were tested in the spontaneous alternation, novel object recognition and plus-maze discriminative avoidance tasks. The control group received intramuscular injections of vegetable oil (vehicle), and the TP group received injections of TP (10 mg/kg, i.m.). The injections were administered for 40 days, with intervals of 48 hours (chronic treatment) or in a single injection (acute treatment). In addition to the behavioral assessments, we performed biochemical analyzes as indicators of the endocrine effects of the treatment. Our results show that chronic treatment with a supraphysiological dose of TP caused memory impairments in the novel object recognition and the discriminative avoidance tasks. The spatial working memory (evaluated by spontaneous alternation task) was not affected. Also, we did not observe changes in anxiety levels. Regarding the biochemical parameters, chronic treatment increased serum levels of glutamicpyruvic transaminase, an indicator of hepatic and pancreatic lesions (as those observed after chronic use of these substances in humans). On the other hand, acute treatment with PT did not promote significant changes in any of these parameters when compared to the control group. In summary, we conclude that chronic treatment with a supraphysiological dose of testosterone propionate produces memory deficits in novel object recognition and retrieval of the discriminative avoidance task in adult male rats / A utiliza??o e a busca por subst?ncias que aumentem a masculinidade, a for?a e a pot?ncia sexual n?o ? recente. Com o tempo, essa busca auxiliou no direcionamento de pesquisas na ?rea, levando a descoberta do principal horm?nio masculino a testosterona em meados da d?cada de 30. A partir desse momento, in?meros compostos foram sintetizados com o intuito de mimetizar os efeitos deste horm?nio, aos quais hoje chamamos genericamente de Esteroides Anab?licos Androg?nicos (EAA). A princ?pio, esses EAA foram sendo produzidos com prop?sitos terap?uticos. No entanto, iniciou-se o uso crescente desses compostos com outras finalidades, principalmente para a melhoria de desempenho em atletas. Al?m disso, estudos recentes t?m demonstrado que os EAA est?o sendo cada vez mais utilizados por n?o atletas, por indiv?duos que n?o s?o atletas, mas, buscam um corpo esteticamente perfeito. Paralelamente, o crescente abuso dos EAA com finalidades n?o cl?nicas pode promover uma s?rie de altera??es fisiol?gicas nocivas, tais como problemas card?acos, hep?ticos, respirat?rios e tamb?m psicol?gicos como altera??es de humor, nos n?veis de ansiedade e na agressividade. A exposi??o a doses suprafisiol?gicas de EAA est? associada com altera??es comportamentais, contudo, pouco se sabe sobre os efeitos dos EAAs sobre as fun??es cognitivas. Neste trabalho, mimetizamos o abuso de EAA em humanos atrav?s da administra??o intramuscular de uma dose suprafisiol?gica de propionato de testosterona (PT), em ratos, com o objetivo de investigar os efeitos desse tratamento sobre diferentes aspectos das fun??es cognitivas, especialmente aprendizado, mem?ria e ansiedade. Ratos Wistar machos adultos foram submetidos aos testes de alterna??o espont?nea, reconhecimento de objetos e esquiva discriminativa em labirinto em cruz elevado. O grupo controle recebeu inje??es intramusculares de ?leo vegetal (ve?culo); e o grupo testosterona recebeu inje??es de PT (10 mg/kg, i.m.). As inje??es foram administradas por 40 dias, com intervalos de 48 horas (tratamento cr?nico) ou em uma ?nica inje??o (tratamento agudo). Al?m das avalia??es comportamentais, foram realizadas an?lises bioqu?micas como indicadores dos efeitos end?crinos do tratamento. Nossos resultados mostram que o tratamento cr?nico com uma dose suprafisiol?gica de PT acarretou preju?zos na mem?ria de reconhecimento de objetos novos e na evoca??o da tarefa da esquiva discriminativa. A mem?ria espacial operacional (avaliada pelo teste de alterna??o espont?nea) n?o foi afetada bem como n?o observamos altera??es nos n?veis de ansiedade. Em rela??o aos par?metros bioqu?micos avaliados, o tratamento cr?nico elevou os n?veis s?ricos da transaminase glut?mica pir?vica (TGP), um indicador da presen?a de les?es hep?ticas e pancre?ticas (assim como as observadas ap?s o uso cr?nico dessas subst?ncias em humanos). Por outro lado, o tratamento agudo com PT n?o promoveu altera??o significativa em nenhum dos par?metros avaliados, quando comparados ao grupo controle. Em s?ntese, podemos concluir que o tratamento cr?nico com uma dose suprafisiol?gica de testosterona produz d?ficits de mem?ria de reconhecimento de objetos bem como preju?zos na mem?ria na tarefa da esquiva discriminativa em ratos machos adultos

Made available in DSpace on 2014-12-17T15:37:03Z (GMT). No. of bitstreams: 1 ThiezaGASGM_DISSERT.pdf: 786174 bytes, checksum: fd475af7fc805fbc9f6633c6413d9035 (MD5) Previous issue date: 2011-05-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Treatment of major depression, posttraumatic stress disorder and other psychopathologies with antidepressants can be associated with improvement of the cognitive deficits related to these disorders. Although the mechanisms of these effects are not completely elucidated, alterations in extinction of aversive memories are believed to be present in these psychopathologies. Moreover, researches with laboratory animals usually focus on male subjects, and we have recently verified that extinction of an aversive task is reduced in female rats when compared to males. In the present study, female rats were long-term treated with clinically used antidepressants (fluoxetine, nortriptyline or mirtazapine) and tested in the plus-maze discriminative avoidance and forced swimming tests in order to evaluate learning, memory, extinction, anxiety and depression-related behaviors. All groups learned the task, but learning was somewhat faster in nortriptyline and mirtazapine-treated animals . Task retrieval was also showed by all experimental groups. Chronic treatment with fluoxetine, but not with the other antidepressants, increased extinction of the discriminative task. In the forced swimming test, animals treated with fluoxetine and mirtazapine showed decreased immobility duration. In conclusion, antidepressants interfere with learning and female rats treated with fluoxetine presented increased extinction of the aversive memory task. On the other hand, both fluoxetine and mirtazapine were effective in the forced swimming test, suggesting dissociation between the antidepressant effects and the extinction of aversive memories / Os tratamentos de depress?o, transtorno de estresse p?s-traum?tico e outras psicopatologias que se utilizam de antidepressivos podem estar associados ? melhora de d?ficits cognitivos relacionados a esses transtornos. Embora os mecanismos pelos quais a melhora nos d?ficits cognitivos ocorre n?o estejam totalmente esclarecidos, altera??es na extin??o de mem?rias aversivas podem estar presentes nestas psicopatologias. Al?m disso, pesquisas com animais de laborat?rio geralmente s?o realizadas com indiv?duos do sexo masculino, e recentemente verificamos que a extin??o de uma tarefa aversiva ? diminu?da em ratas quando comparada ao desempenho de ratos. No presente estudo, ratas Wistar foram tratadas prolongadamente com antidepressivos utilizados na cl?nica (nortriptilina, fluoxetina ou mirtazapina) e testadas na esquiva discriminativa em labirinto em cruz elevado e no teste do nado for?ado, a fim de avaliar a aprendizagem, a mem?ria, a extin??o, a ansiedade e comportamentos relacionados ? depress?o. A explora??o do bra?o aversivo na sess?o de treino foi semelhante em todos os grupos, mostrando que todos os grupos aprenderam a tarefa, havendo, por?m, uma melhora no desempenho dos grupos tratados com nortriptilina e mirtazapina. Na sess?o teste todos os animais evocaram a tarefa. O tratamento prolongado com a fluoxetina, mas n?o com os outros antidepressivos, promoveu uma melhora na extin??o da mem?ria aversiva da EDLC. No teste de nado for?ado, os animais tratados com fluoxetina e mirtazapina apresentaram diminui??o na dura??o da imobilidade, comparados ao ve?culo. Em conclus?o, os antidepressivos podem interferir no aprendizado, mas n?o na evoca??o de mem?rias aversivas. Al?m disso, ratas tratadas com fluoxetina apresentam um aumento da extin??o da tarefa aversiva, em compara??o ao ve?culo, enquanto os demais tratamentos impediram a extin??o dessa tarefa. Al?m disso, tanto a fluoxetina como a mirtazapina foram eficazes no teste de nado for?ado, sugerindo dissocia??o entre os efeitos antidepressivos e extin??o de mem?rias aversivas

Les études d'association sur un génome complet (GWAS) sont conçues pour découvrir les combinaisons de points de polymorphisme (SNP) associées à des maladies. La découverte de ces associations permet d'élaborer de meilleures stratégies pour détecter, traiter ou prévenir les maladies. Récemment, l'utilisation de techniques d'extraction de patterns discriminatif a été investiguée dans le cadre de problématiques GWAS. Toutefois, la découverte de combinaisons de SNP dans de grands jeux de données GWAS est encore difficile à cause de la complexité des algorithmes utilisés. La thèse se propose donc d'améliorer l'état de l'art des approches d'extraction de motifs discriminants, dans le cadre d'extraction de combinaisons de SNP corrélées à un phénotype d'intérêt. Plusieurs solutions ont été proposées, s'attaquant aux problèmes majeurs en GWAS : évaluation de la force d'association, découverte efficace de combinaisons de SNP et visualisation de ces combinaisons. Les approches proposées sont également prometteuses pour d'autres tâches de bioinformatique comme la découverte d'expressions génique, la détection de motifs de phosphorylation et la détection de motifs de régulation. / Discovering high-order SNP combinations associated with diseases is an important task of bioinformatics. Once new genetic associations are identified, they can be used to develop better trategies to detect, treat and prevent the diseases. Recently, this issue has been effectively tackled with discriminative pattern mining algorithms. However, the number of SNPs is often very large, discovering of SNP combinations remains many challenges. To address these challenges this thesis has been advanced the state-of-the-art discriminative pattern mining techniques to discover SNP combinations associated with interesting phenotype. Different solutions have been proposed in this thesis to tackle GWAS analysis. These solutions focus on efficient association strength evaluation, statistically significant discriminative SNP combinations discovery and interesting SNP combinations visualization. The solutions proposed in this thesis are also promising for other tasks of bioinformatics such as differential gene expression discovery, phosphorylation motifs detection and regulatory motif combination mining.

This study is a historical analytical investigation and theological interpretation of Wesleyan Methodists' political teaching and practice in Zimbabwe from 1891 to 1980. In an attempt to come up with an informed interpretation of the political teaching and activities, the study traced Wesleyan Methodist political praxis John Wesley, the founder of Methodism and interpreted his teaching and practice from a third world perspective. That perspective was used as a basis for evaluating the contextualisation of his teaching by Wesleyan Methodists in Zimbabwe. The Zimbabwean Wesleyan Methodists' political teaching and practice during the colonial era were explored using four themes: politics of land, race relationships, Federation and war. Two hypothetical statements were tested in this study: Wesleyan Methodism outlines a framework for constructive participation in politics, and the Wesleyan Methodist Church in Zimbabwe provided and supported positions of political leadership in Zimbabwe. The objectives of this study are to: unveil successes and failures of Wesleyan Methodists in Zimbabwean political arena, expose the historical significance of Wesleyan Methodist influence in politics for Zimbabwean history and present a historical account of the Wesleyan Methodist Church in Zimbabwe. The methodology preferred in this study included oral history and a combination of the ecumenical and southern approaches to Church history. The study utilised archival and oral data as primary sources, the translation model of contextual theology, holistic framework for analysing history, the principle of the overriding right and the conflict transformation model as part of the methodology. Through the use of the translation model of contextual theology, the study revealed how John Wesley used principles from the Christian message and Church tradition in addressing his political context. The study exposed that John Wesley was obsessed with accountability to God and constituency, respect for every person, respect for political structures as well as authorities and relationships among people as fundamental pillars in political activities. He based these on his understanding of God's free grace, people's liberty to accept or reject that grace and the validity of popular religious expression. The study revealed that Wesleyan Methodists in Zimbabwe had a special relationship with the colonial government due to an invitation by Cecil John Rhodes for the church to participate in the Pioneer Column. The relationship determined how retrogressive or progressive ministers responded to government requirements and made demands on government until the country's independence in 1980. The study also exposed how retrogressive Wesleyan Methodists moved from acceptance and collaboration to acceptance and selective rejection of colonial policies and how both retrogressive and progressive ministers employed the concept of non-contestation of participation in armed conflict and throwing one’s lot on the expected side. It also showed how progressive ministers contributed to the political emancipation of Africans and the role played by the mission-educated elite in Zimbabwe. The study ended with pointing out that Zimbabwean Wesleyan Methodist political teaching and practice had very bright future prospects at the independence of the country in 1980. / Thesis (PhD)--University of Pretoria, 2011. / Church History and Church Policy / Unrestricted

Spoken communication is only one of many types of human interaction with the environment. The aim of this thesis is to propose a theory of spoken communication based on basic principles of cognition, which govern all our behaviour. To this end, two established theoretical positions are integrated: 1) the skilled intentionality framework (an enactive view of cognition) and 2) a discriminative approach to human communication. According to the resulting theory, communication is a skilful shaping of an interlocutor's envi- ronment which serves to fulfil the agent's positively biased expectations about her own situation. Language is presented as an assemblage of sociomaterial regularities that make this skilful behaviour possible. The suggested perspec- tive is radically action-oriented, in contrast with traditional representational, content-based approaches. The proposed view is then applied to two specific phenomena widely studied within speech sciences (namely categoricality of speech and turn taking) and is confronted with selected empirical findings. Possibilities of empirical testing of the suggested theory are discussed.

Tato práce pojednává o modelování v podprostoru parametrů směsí gaussovských rozložení pro rozpoznávání mluvčího. Práce se skládá ze tří částí. První část je věnována skórovacím metodám při použití sdružené faktorové analýzy k modelování mluvčího. Studované metody se liší převážně v tom, jak se vypořádávají s variabilitou kanálu testovacích nahrávek. Metody jsou prezentovány v souvislosti s obecnou formou funkce pravděpodobnosti pro sdruženou faktorovou analýzu a porovnány jak z hlediska přesnosti, tak i z hlediska rychlosti.  Je zde prokázáno, že použití lineární aproximace pravděpodobnostní funkce dává výsledky srovnatelné se standardním vyhodnocením pravděpodobnosti při dramatickém zjednodušení matematického zápisu a tím i zvýšení rychlosti vyhodnocování. Druhá část pojednává o extrakci tzv. i-vektorů, tedy nízkodimenzionálních reprezentací nahrávek. Práce prezentuje dva přístupy ke zjednodušení extrakce. Motivací pro tuto část bylo jednak urychlení extrakce i-vektorů, jednak nasazení této úspěšné techniky na jednoduchá zařízení typu mobilní telefon, a také matematické zjednodušení umožněňující využití numerických optimalizačních metod pro diskriminativní trénování.  Výsledky ukazují, že na dlouhých nahrávkách je zrychlení vykoupeno poklesem úspěšnosti rozpoznávání, avšak na krátkých nahrávkách, kde je úspěšnost rozpoznávání nízká, se rozdíly úspěšnosti stírají. Třetí část se zabývá diskriminativním trénováním v oblasti rozpoznávání mluvčího. Jsou zde shrnuty poznatky z předchozích prací zabývajících se touto problematikou. Kapitola navazuje na poznatky z předchozích dvou částí a pojednává o diskriminativním trénování parametrů extraktoru i-vektorů.  Výsledky ukazují, že při klasickém trénování extraktoru a následném diskriminatviním přetrénování tyto metody zvyšují úspěšnost.

This report analyzes the difference between discriminative and generative image classifiers when tested on noise. The generative classifier was a maximum-likelihood based classifier using a normalizing flow as the generative model. In this work, a coupling flow such as RealNVP was used. For the discriminative classifier a convolutional network was implemented. A detailed description of how these classifiers were implemented is given in the report. The report shows how this generative classifier outperforms the discriminative classifier when tested on adversarial noise. However, tests are also conducted on salt and pepper noise and Gaussian noise, here the results show that the generative classifier gets outperformed by the discriminative classifier. Tests were also conducted on Gaussian noise once both classifiers had been trained on Gaussian noise, the results from these tests show that the discriminative classifier performs significantly better once trained on Gaussian noise. However, the generative classifier does only show marginal increases in performance and performs worse on clean data once trained on Gaussian noise. / Den här rapporten analyserar skillnaden mellan diskriminativa och generativa modellklasser för bildigenkänning när de testas på brus. Den generativa modellklassen var en maximum-likelihood baserad generativ klassifikationsmodell. Inom detta arbete användes kopplingsflödet RealNVP. För den diskriminativa bildigenkänningsmodellen så implementerades ett faltningsnätverk. En detaljerad beskrivning för hur dessa bildigenkänningsmodeller genomfördes är given i rapporten. Rapporten visar hur den generativa modellklassen överträffar den diskriminativa modellklassen när de testas på adversarialt brus. Testerna utförs emellertid med salt och peppar brus och Gaussiskt brus, för dessa visar resultaten att den generativa modellklassen överträffas av den diskriminativa modellklassen. Den generativa modellklassen visar emellertid endast marginella ökningar i prestanda, och har en sämre prestanda på ren data efter att den tränats på Gaussiskt brus. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

No description available.

Feedback is discussed in many disciplines. In behavior analysis, it has been discussed in terms of its functions, many coming to different conclusions. The present study evaluated whether therapists' preferred temporal and format of feedback shifted or changed during acquisition or maintenance of skills implementing a tact program using a token economy system after a brief exposure to all possible feedback combinations. Three participants completed a questionnaire before they were exposed to a feedback sampling phase and preferred feedback phase. Preferred way of recieving feedback was asked at the beginning of each session. Two out of three participants switched preferences after achieving mastery of task. Task mastery may make feedback delivered at the end of a session more desirable while task acquisition may make feedback delivered at the end of a trial more valuable. Limitations and future research were discussed.

La détection d'homologues lointains est essentielle pour le classement fonctionnel et structural des séquences protéiques et pour l'amélioration de l'annotation des génomes très divergents. Pour le classement des séquences, nous présentons la méthode "ILP-SVM homology", combinant la programmation logique inductive (PLI) et les modèles propositionnels. Elle propose une nouvelle représentation logique des propriétés physico-chimiques des résidus et des positions conservées au sein de l'alignement de séquences. Ainsi, PLI trouve les règles les plus fréquentes et les utilise pour la phase d'apprentissage utilisant des modèles d'arbre de décision ou de machine à vecteurs de support. La méthode présente au moins les mêmes performances que les autres méthodes trouvées dans la littérature. Puis, nous proposons la méthode CASH pour annoter les génomes très divergents. CASH a été appliqué à Plasmodium falciparum, mais reste applicable à toutes les espèces. CASH utilise aussi bien l'information issue de génomes proches ou éloignés de P. falciparum. Chaque domaine connu est ainsi représenté par un ensemble de modèles évolutifs, et les sorties sont combinées par un méta-classificateur qui assigne un score de confiance à chaque prédiction. Basé sur ce score et sur des propriétés de co-ocurrences de domaines, CASH trouve l'architecture la plus probable de chaque séquence en appliquant une approche d'optimisation multi-objectif. CASH est capable d'annoter 70% des domaines protéiques de P. falciparum, contre une moyenne de 58% pour ses concurrents. De nouveaux domaines protéiques ont pu être caractérisés au sein de protéines de fonction inconnue ou déjà annotées.