Por volta de 1764 aparece um novo ramo da ciência - A teoria de controle - quando James Watt consertou uma máquina Newcomen e percebeu que essa era ineficiente, e criou um sistema de controle de velocidades. A evolução destes sistemas controladores pode ser observada no controle utilizando a equação de Riccati dependente de estados (SDRE). Apesar de ser uma técnica muito avançada em relação à capacidade de realizar o controle, alguns problemas precisam ser encarados quanto à sua utilização, como a necessidade de se ter recursos computacionais de alto nível e custo. Essas questões podem impedir o uso da técnica SDRE em alguns sistemas. Uma solução para este problema é apontada através do uso de uma rede neural (RNA) chamada de Rede Neural com Estados de Eco (ESN). As RNAs possuem arquiteturas baseadas em redes neurais biológicas para que tenhamos resultados desejados na saída. Para que essa saída seja satisfatória a rede neural passa por um processo de treinamento. Sendo assim, usase os dados de comportamento do SDRE para a realização do treinamento da ESN. Depois disso, realizam-se testes quanto à eficiência da rede neural no controle do sistema a ser controlado e ao custo computacional. Os resultados são comparados aos obtidos com o controle ESN. Este teste foi realizado para um sistema micro eletromecânico e o controle da suspensão ativa de um half-car. Os resultados obtidos foram positivos, pois a ESN conseguiu realizar o controle utilizando menos tempo de processamento em relação ao SDRE, além de possuir uma estrutura base fixa, possibilitando ajustes para realização de diferentes tipos de controle. / In around 1764, it emerged a new branch of science – the theory of control - when James Watt was given a model Newcomen engine to repair. He realised that it was hopelessly inefficient and began to work to improve the design. He did a velocit controller to solve the problem. The evolution of these systems is shown in State-dependent Riccati equation (SDRE) techniques. Although it is a very advanced technique in relation to the capacity of performing control, some problems have to be faced for its use, as the necessity of computational resources of high level and cost, which may impede the use of SDRE in some systems. The solution for these problems is pointed out in this study by the use of Echo State Neural Networks (ESNs). These neural networks have inputs and outputs and the inputs are processed through the use of algorithms in order to reach the desired results, and for that the neural network has to be under a task of training. After that we use the behavioral SDRE data for the training followed by the neural network efficiency test for the system control and for the computational cost. The results are compared to the ones obtained with the ESN control. This test was realized for a micro eletromechanical system and the control of the active suspension of a half-car. The results were positive as the ESN could perform the control in a short time in relation to the SDRE. There is also a fixed structure which makes possible some adjusts for different kinds of control.

Made available in DSpace on 2014-12-17T15:36:56Z (GMT). No. of bitstreams: 1 RafaelNBS.pdf: 1024882 bytes, checksum: c829a50c3f00bc3a4f9a1f5bc84386a4 (MD5) Previous issue date: 2009-05-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In most cultures, dreams are believed to predict the future on occasion. Several neurophysiological studies indicate that the function of sleep and dreams is to consolidate and transform memories, in a cyclical process of creation, selection and generalization of conjectures about the reality. The aim of the research presented here was to investigate the possible adaptative role of anticipatory dreams. We sought to determine the relationship between dream and waking in a context in which the adaptive success of the individual was really at risk, in order to mobilize more strongly the oneiric activity. We used the entrance examination of the Federal University of Rio Grande do Norte (UFRN) as a significant waking event in which performance could be independently quantified. Through a partnership with UFRN, we contacted by e-mail 3000 candidates to the 2009 examination. In addition, 150 candidates were approached personally. Candidates who agreed to participate in the study (n = 94) completed questionnaires specific to the examination and were asked to describe their dreams during the examinaton period. The examination performance of each candidate in the entrance examination was provided by the UFRN to the researcher. A total of 45 participants reported dreams related to the examination. Our results show a positive correlation between performance on the examination and anticipatory dreams with the event, both in the comparison of performance on objective and discursive, and in final approval (in the group that not dreamed with the exam the rate of general approval, 22,45%, was similar to that found in the selection process as a whole, 22.19%, while for the group that dreamed with the examination that rate was 35.56%). The occurrence of anticipatory dreams reflectes increased concern during waking (psychobiological mobilization) related to the future event, as indicated by higher scores of fear and apprehension, and major changes in daily life, in patterns of mood and sleep, in the group that reported testrelated dreams. Furthermore, the data suggest a role of dreams in the determination of environmentally relevant behavior of the vigil, simulating possible scenarios of success (dream with approval) and failure (nightmares) to maximize the adaptive success of the individual / Nas mais diversas culturas, atribui-se aos sonhos a capacidade de prever o futuro. Diversos estudos neurofisiol?gicos indicam que a fun??o do sono e dos sonhos ? consolidar e transformar mem?rias, em um processo c?clico de cria??o, sele??o e generaliza??o de conjecturas sobre a realidade. Com o objetivo de investigar cientificamente a poss?vel fun??o antecipat?ria dos sonhos, buscamos descrever a rela??o entre sonho e vig?lia subseq?ente num contexto em que o sucesso adaptativo do indiv?duo realmente estivesse em risco, de modo a mobilizar mais fortemente a atividade on?rica. Utilizamos o exame vestibular da Universidade Federal do Rio Grande do Norte (UFRN) como evento significativo da vig?lia. Atrav?s de uma parceria com a UFRN, contatamos por e-mail 3000 candidatos ao Vestibular 2009. Al?m disso, 150 candidatos foram abordados pessoalmente. Os candidatos que aceitaram participar do estudo (n=94) preencheram question?rios espec?ficos sobre a prova e lhes foi solicitado que relatassem um sonho relacionado ? prova, caso algum houvesse ocorrido nos dias que a antecederam. O desempenho final de cada candidato no exame vestibular foi fornecido ao pesquisador pela UFRN. Ao todo 45 participantes relataram que sonharam com a prova. Nossos resultados mostram uma correla??o positiva entre o desempenho na prova e sonhos antecipat?rios com o evento, tanto na compara??o do desempenho nas provas objetivas e discursivas, quanto na aprova??o final (no grupo que n?o sonhou com a prova o ?ndice de aprova??o geral, 22,45%, foi semelhante ao encontrado no processo seletivo como um todo, 22,19%; j? para o grupo que sonhou com a prova esse ?ndice foi 35,56%). A ocorr?ncia desses sonhos antecipat?rios refletiu uma maior preocupa??o na vig?lia (mobiliza??o psicobiol?gica) em torno do evento futuro (maiores escores de medo e apreens?o, al?m de maiores altera??es no cotidiano, nos padr?es de humor e de sono). Al?m disso, os dados sugerem um papel importante dos sonhos na determina??o de comportamentos ecologicamente relevantes da vig?lia, simulando poss?veis cen?rios de sucesso (sonhar com aprova??o) e fracasso (pesadelos) para maximizar o sucesso adaptativo do indiv?duo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo é resultado do exame das aproximações feitas entre o pensamento do filósofo holandês Baruch de Espinosa e as pesquisas e reflexões atuais do biofísico Henri Atlan e do neurobiólogo António Damásio. O exame consistiu, primeiramente, na identificação dos conceitos de Espinosa utilizados nas obras desses autores, o que envolveu destacar as relações que os próprios cientistas reconhecem ter com o pensamento do filósofo e também encontrar outras relações legítimas, não indicadas pelos autores. O resultado dessa etapa inicial foi a reunião das reflexões em torno de dois temas: 1. a teoria do conatus e 2. a teoria mente-corpo espinosista. O exame consistiu também na discussão sobre o modo como esses conceitos são utilizados por Espinosa e pela detecção de suas novas significações no contexto das pesquisas de Damásio e Atlan. Além disso, foi realizado um exame crítico dessas apropriações pela investigação de perdas e reduções no pensamento do filósofo. As aproximações empreendidas pelos autores à teoria mente-corpo espinosista nem sempre são consistentes, ou por falta de evidências que as justifiquem, como no caso de Atlan, ou pela adoção de uma perspectiva metafísica monista distinta da de Espinosa, como no caso de Damásio. Mas, com relação à noção de conatus, as assimilações são melhor sucedidas. O esforço de perseverar no ser pode ser traduzido adequadamente como o ímpeto que rege os mecanismos homeostáticos que governam a vida ou a força responsável pela auto-organização dos sistemas naturais. / This study is the result of the examination of some approximations made between the thought of the Dutch philosopher Baruch Spinoza and the researches and reflections made in our time by the biophysicist Henri Atlan and the neuroscientist Antonio Damasio. The examination consisted, first, in the identification of Spinozas concepts used in the works of these authors, which involved highlighting the relationships that these scientists recognize with Spinozas thought, and also finding some other legitimate relationships that were not indicated by them. The result of this initial task was the gathering of the reflections around two themes: (1) conatus theory, and (2) Spinozas mind-body theory. The examination also consisted in the discussion of how these concepts are used by Spinoza, and the detection of their new meanings in the context of Damasios and Atlans researches. In addition, a critical assessment of these appropriations was made, in which losses and reductions of the philosophers thought were analyzed. Not always the approximations made by the two authors with Spinozas mind-body theory are consistent, be it in virtue of a lack of evidence to justify them, as in the case of Atlan, or due to the adoption of a monistic metaphysical perspective different from that of Spinoza, as in the case of Damasio. However, concerning the notion of conatus the assimilations proved more successful. The "effort to persevere in being" can be properly translated as the impetus that rules the homeostatic mechanisms that govern life or as the force responsible for the natural systems self-organization.

Finding an indicator that can point to a high risk group for suicide has long been a desirable aid for the prevention of completed suicides. The studies reviewed in this essay presume that a biological aspect can point out the high risk individual. The focus of the studies lies on the serotonin 5-hydroxytryptamine (5-HT) monoamine neurotransmitter and cerebrospinal fluid (CSF) 5-hydroxyindoleacetic acid (5-HIAA) which is the principal metabolite of 5-HT in depression. The studies on 5-HT metabolites have led to the belief that these may play a key role in the neurochemistry of suicidal behaviour. It is suggested that the core behavioural effect of low CSF 5-HIAA concentration might result in an increase in impulsive and violent behaviour to self and others. The predictability is based on the fact that patients with low CSF 5-HIAA are more prone to reattempt and complete suicide by violent means. A number of well-designed studies concerning suicidal individuals and control subjects have however not shown any difference in concentration of CSF 5-HIAA in suicide attempters compared to non-suicide attempters which could be explained by methodological flaws. Low CSF 5-HIAA does seem to characterize the high risk individual, but it is not yet determined what role it plays in actual suicidality.

Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2016-12-21T16:15:17Z No. of bitstreams: 2 Dissertação - Adailson Costa dos Santos - 2016.pdf: 2240371 bytes, checksum: 26681af0c3644ad8f8a4138b7fabb75d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-26T12:51:46Z (GMT) No. of bitstreams: 2 Dissertação - Adailson Costa dos Santos - 2016.pdf: 2240371 bytes, checksum: 26681af0c3644ad8f8a4138b7fabb75d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-12-26T12:51:46Z (GMT). No. of bitstreams: 2 Dissertação - Adailson Costa dos Santos - 2016.pdf: 2240371 bytes, checksum: 26681af0c3644ad8f8a4138b7fabb75d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-05-10 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / This research analyzes the perspectives of Stanislavski’ system as proposed by the Russian director Constantin Stanislavski (1863 – 1938) in dialogue with recent proposals of the neurobiology of emotions. It begins with the main definitions about emotions in western history, starting with Plato and reaching conceptions posed by the Portuguese neuroscientist Antonio Damásio (1944) who investigate the production and interpretations of the human emotions. The work focuses on the proposals of the “organic” interpretation by Stanislavski, mainly on the concept and procedures of what has been called emotive memory. This discussion is based on the findings of the French psychologist Théodule-Armand Ribot (1839- 1916), and his concept of affective memory (in French, la memoire affective; In Russian, Affectivnaia pamiat’) that underpinned the concept used by Stanislavski. At the end, the thesis establishes the neurobiological construction that pervade the Stanislavski’ system. / Este trabalho analisa as perspectivas do sistema Stanislávski propostas pelo encenador russo Constantin Stanislávski (1863-1938), estabelecendo-se um diálogo com as recentes pesquisas da neurobiologia das emoções. Faz-se um estudo do percurso histórico sobre as emoções na história do pensamento ocidental, partindo de Platão na história antiga e culminando na compreensão das concepções do neurocientista português Antônio Damásio (1944) sobre a produção e interpretação das emoções humanas. Em seguida, investiga-se as propostas de interpretação “orgânica” de Stanislávski, focando principalmente no conceito e procedimentos da chamada memória emotiva. Realiza-se um estudo das concepções do psicólogo francês Théodule-Armand Ribot (1839-1916) sobre o conceito de memória afetiva (em francês, la memoire affective; em russo, Affectivnaia pamiat’) que dá suporte ao conceito utilizado por Stanislávski. Ao final, traça-se um diálogo dos conhecimentos apresentados onde se compreendem as construções biológicas que permeiam o sistema.

Post-traumatic stress disorder (PTSD) is a disabling condition that afflicts 1-10% of the general population, with twice as high lifetime prevalence for women than men. Treatments exist, but none have proven reliable and consistent efficacy. A large minority of patients remain treatment-resistant despite undergoing several different types of treatment over extended periods of time. Recently completed studies in the U.S. and in Switzerland have demonstrated the potential of 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for treatment-resistant PTSD. One of the major problems of treating PTSD is the patients’ fear state and inability to form a therapeutic alliance. Both these issues can be facilitated through administration of MDMA; the psychological effects - such as heightened empathy, increased openness and diminished anxiety – seem well-suited for therapeutic purposes. The rationale behind treating PTSD with MDMA has been indicated in neuroimaging studies; MDMA affects some of the neural structures altered in patients with PTSD, most notably the amygdala and the ventromedial prefrontal cortex. Using the Schedule 1 substance MDMA for this purpose is however controversial; animal studies have indicated that MDMA is neurotoxic, although no adverse effects on humans related to incidental use of MDMA in a controlled setting have been found. In conclusion, the data support that MDMA may be an efficient tool for treating PTSD, as well as safe and effective to use in a clinical context.

L'holoprosencéphalie (HPE) est une maladie rare due à une anomalie du développement précoce du prosencéphale. Les gènes impliqués appartiennent à des voies de signalisation cruciales pour le développement embryonnaire telles que les Nodal, Shh et Fgf. Des mutations de ces gènes n'expliquent que 30% des cas d'HPE. Différentes stratégies ont été mises en œuvre pour déterminer de nouveaux gènes responsables de l'HPE. Récemment, des délétions du gène DLL1, un ligand du récepteur Notch ont été identifiées chez des patients HPE. L'objectif de mon travail de thèse était de tester l'hypothèse d'un rôle de la voie Notch au cours du développement précoce du prosencéphale. Dans ce but, une inhibition de la voie Notch a été réalisée en utilisant une culture ex ovo d'embryon de poulet. Grâce à cela, j'ai pu identifier une activité de la voie Notch au niveau de l'hypothalamus présomptif, une structure ventrale du cerveau antérieur. Une approche transcriptomique a ensuite permis d'identifier les dérégulations survenant lors de l'inhibition pharmacologique de la voie Notch. Les expressions des cibles trancriptionnelles de la voie Notch telles que Hes5, Hey1, Ascl1 ou Nhlh1 m'ont permis de suggérer un modèle d'action par inhibition latérale lors de la neurogénèse de l'hypothalamus en développement. Les données transcriptomiques générées m'ont permis d'identifier de nouveaux gènes marqueurs de l'hypothalamus dont l'expression est sous l'influence de la voie Notch. Nos résultats suggèrent que ces gènes appartiennent à une boucle de régulation comprenant la voie Notch et des facteurs de neurogénèse tels que les gènes proneuraux. Mon travail a également permis de montrer que l'expression du gène majeur de l'HPE, le gène Shh, requérait une activité de la voie Notch précisément au niveau de l'hypothalamus. En conclusion, mes résultats montrent que la voie Notch contribue au développement précoce du cerveau. Ce constat ajoute un autre niveau de complexité à l'apparition de l'HPE et apporte de nouveaux arguments en faveur d'un modèle « multi-hit » pour cette pathologie. / Holoprosencephaly (HPE) is a rare disease corresponding to a failure of early prosencephalon development. Genes involved in HPE, belong to crucial signalling pathways for embryonic development as Nodal, Shh and Fgf. Mutations in these genes could explain only 30% of HPE cases. Different strategies were used to identify new genes in HPE. Recently, deletions of DLL1, a ligand of Notch receptor, have been identified in HPE patients. The aim of my thesis was to test hypothesis that Notch pathway has a role during the early prosencephalon development. First, I performed a pharmacological inhibition of Notch pathway in embryos that were cultured ex ovo. Thus, I could identify Notch activity at the level of primordium hypothalamus, a ventral structure of prosencephalon. Then, transcriptomic analyses were performed to identify deregulations occurring during Notch inhibition. Expressions of well known transcriptional targets of Notch pathway, Hes5, Hey1, Ascl1 and Nhlh1, indicated that Notch pathway might act by lateral inhibition in the neurogenesis of developing hypothalamus. From transcriptomic data, we identified novel markers of developing hypothalamus that will be regulated by Notch pathway. Our results suggest that these novel genes could be involved in the regulatory loop associating with Notch pathway and proneural genes. Then, I demonstrated that Notch activity is required to maintain Shh expression, a major gene involved in HPE, particularly in the hypothalamus. To conclude, adding the Notch pathway in the signalling pathway network involved in prosencephalon development, we provide other complexity level in the HPE appearance. Thus, these results support the hypothesis of a « multi-hit » model of HPE.

\ / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Au cours de la différenciation neuronale, les gènes proneuraux induisent l'expression de nombreux gènes appartenant à différentes familles. Deux de ces familles constituent l'intérêt de cette étude à savoir les facteurs de transcription à doigts à zinc Myt/NZF et IA1/INSM1. Chez le xénope, il a été démontré que XMyT1 coopère avec les facteurs bHLH afin d'induire la neurogenèse de manière insensible à la voie de signalisation Delta/Notch (Bellefroid et al. 1996). Son mode d'action n'est pas connu et nécessite d'être approfondi afin de mieux comprendre son rôle au cours de la neurogenèse. Lors d'expériences utilisant un gène rapporteur, la protéine XMyT1 a été décrite comme activateur de la transcription tandis que la protéine orthologue NZF3 chez le rat se comporte comme répresseur de la transcription (Yee et al. 1998). Récemment, il a été rapporté que les protéines NZF1 et NZF2 chez la souris interagissent avec le corépresseur Sin3& / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

A la suite d’un criblage in silico nous avons identifié un nouveau gène codant pour une protéine à domaine BTB-POZ, XBTBD6.<p>Nous avons déterminé que la protéine XBTBD6 est une protéine cytoplasmique. Dans les cellules Hela, CHO, U2OS et COS7 la protéine XBTBD6 est localisée dans des corpuscules cytoplasmiques, localisation similaire à celle des protéines XBTBD3, HBTBD1 et HBTBD2. Nous avons observé que la partie N-terminale de la protéine, contenant le domaine BTB-POZ, est localisée dans la cellule comme la protéine entière ;par contre la partie C-terminale est exclusivement nucléaire. De plus, nous avons observé que XBTBD6 est localisée de façon diffuse dans le cytoplasme des cellules Neuro2A, 9L et 518A2e. Nous avons montré que la protéine XBTBD6 homodimérise et hétérodimérise avec XBTBD3 et XBTBD2 et qu’elle interagit avec l’ubiquitine ligase E3 XCullin 3. L’ensemble de ces interactions nécessite la présence du domaine BTB-POZ. Ces données montrent que les protéines BTBD6, BTBD3, BTBD1 et BTBD2 possèdent des propriétés communes indiquant qu’elles appartiennent à un sous groupe de la famille des protéines à domaine BTB-POZ.<p>Le profil d’expression a été analysé par la technique de protection à la RNAse et par hybridation in situ. Les résultats montrent que ce gène est fortement exprimé dans le système nerveux adulte et embryonnaire. Des expériences de surexpression par micro-injection d’ARNm ont permis de placer le gène XBTBD6 dans la cascade d’activation des gènes proneuraux en aval de XNgnr-1, XNeuroD, Xath3 et Xebf3. Ces résultats montrent que XBTBD6 est un marqueur neuronal chez le xénope. <p>Au cours de l’étude de la fonction du gène XBTBD6, nous avons montré que la surexpression et la perte de fonction de ce gène dans l’embryon de xénope n’induit pas de variation du nombre de neurones dans la plaque neurale. Par contre nous avons observé que la surexpression du gène XBTBD6 dans des cellules Neuro2A en différentiation régule négativement la croissance des neurites.<p>Nous avons élaboré un modèle de fonctionnement biochimique hypothétique où la protéine XBTBD6 fonctionnerait comme protéine adaptatrice dans un complexe d’ubiquitination permettant l’ubiquitination d’une protéine cible. Nous avons recherché les partenaires potentiels de XBTBD6 en utilisant la technique du double hybride en levure mais sans y parvenir.<p> / Doctorat en sciences, Spécialisation biologie moléculaire / info:eu-repo/semantics/nonPublished