La réduction des budgets du domaine spatial et les missions scientifiques traditionnelles ayant des coûts et une complexité croissants a amené la communauté scientifique à se concentrer sur les petits satellites qui fournissent non seulement des résultats scientifiques de valeur, mais permettent aussi de nouvelles applications dans le domaine de la télédétection, de la surveillance environnementale et des télécommunications. De plus, le concept de vol en formation de petits satellites est une technologie-clé pour beaucoup de missions spatiales futures, en améliorant la capacité de survie et réduisant le coût des missions. Ce travail de recherche a un double but : la proposition de modèles innovants de constellations de nano-satellites et de nouvelles approches de routage pour les réseaux de nano-satellites. Cette thèse propose et analyse trois modèles de constellations de nano-satellites dénommés NanoDREAM, NanoiCE et NanoSPHERE, qui fournissent des services de télécommunications aux régions éloignées. Le modèle NanoDREAM est conçu pour le Désert Salar de Uyuni en Bolivie, une région qui détient 70% de la réserve mondiale de lithium. Le modèle NanoiCE est destiné aux Régions Polaires, pour satisfaire les besoins de télécommunications de la communauté scientifique. Le modèle NanoSPHERE est conçu pour fournir une couverture globale de la Terre pour un marché de télécommunications concurrentiel. De plus, nous avons proposé une architecture pour le segment terrestre basée sur la technologie sans fil. Cette architecture a été déployée sur la zone d'exploitation du Désert Salar de Uyuni. Ces modèles ont été développés analytiquement et mis ensuite en œuvre dans le simulateur SaVi afin d'identifier la meilleure constellation satisfaisant les requis de la mission en terme de couverture et en réduisant au minimum le nombre de nano-satellites de la constellation. [...]

Treatments for chronic pain are inadequate, and new options are needed. Nonpharmaceutical approaches are especially attractive with many potential advantages including safety. Light therapy has been suggested to be beneficial in certain medical conditions such as depression, but this approach remains to be explored for modulation of pain. We investigated the effects of light-emitting diodes (LEDs), in the visible spectrum, on acute sensory thresholds in naive rats as well as in experimental neuropathic pain. Rats receiving green LED light (wavelength 525 nm, 8 h/d) showed significantly increased paw withdrawal latency to a noxious thermal stimulus; this antinociceptive effect persisted for 4 days after termination of last exposure without development of tolerance. No apparent side effects were noted and motor performance was not impaired. Despite LED exposure, opaque contact lenses prevented antinociception. Rats fitted with green contact lenses exposed to room light exhibited antinociception arguing for a role of the visual system. Antinociception was not due to stress/anxiety but likely due to increased enkephalins expression in the spinal cord. Naloxone reversed the antinociception, suggesting involvement of central opioid circuits. Rostral ventromedial medulla inactivation prevented expression of light-induced antinociception suggesting engagement of descending inhibition. Green LED exposure also reversed thermal and mechanical hyperalgesia in rats with spinal nerve ligation. Pharmacological and proteomic profiling of dorsal root ganglion neurons from green LED-exposed rats identified changes in calcium channel activity, including a decrease in the N-type (CaV2.2) channel, a primary analgesic target. Thus, green LED therapy may represent a novel, nonpharmacological approach for managing pain.

Chronic pain affects the life of millions of people. Current treatments have deleterious side effects. We have advanced a strategy for targeting protein interactions which regulate the N-type voltage-gated calcium (CaV2.2) channel as an alternative to direct channel block. Peptides uncoupling CaV2.2 interactions with the axonal collapsin response mediator protein 2 (CRMP2) were antinociceptive without effects on memory, depression, and reward/addiction. A search for small molecules that could recapitulate uncoupling of the CaV2.2-CRMP2 interaction identified (S)-lacosamide [(S)-LCM], the inactive enantiomer of the Food and Drug Administration-approved antiepileptic drug (R)-lacosamide [(R)-LCM, Vimpat]. We show that (S)-LCM, but not (R)-LCM, inhibits CRMP2 phosphorylation by cyclin dependent kinase 5, a step necessary for driving CaV2.2 activity, in sensory neurons. (S)-lacosamide inhibited depolarization-induced Ca influx with a low micromolar IC50. Voltage-clamp electrophysiology experiments demonstrated a commensurate reduction in Ca currents in sensory neurons after an acute application of (S)-LCM. Using constellation pharmacology, a recently described high content phenotypic screening platform for functional fingerprinting of neurons that uses subtype-selective pharmacological agents to elucidate cell-specific combinations (constellations) of key signaling proteins that define specific cell types, we investigated if (S)-LCM preferentially acts on certain types of neurons. (S)-lacosamide decreased the dorsal root ganglion neurons responding to mustard oil, and increased the number of cells responding to menthol. Finally, (S)-LCM reversed thermal hypersensitivity and mechanical allodynia in a model of postoperative pain, and 2 models of neuropathic pain. Thus, using (S)-LCM to inhibit CRMP2 phosphorylation is a novel and efficient strategy to treat pain, which works by targeting specific sensory neuron populations.

Os rotavírus do grupo A (RVA) são importantes causadores de diarreias virais em crianças e animais jovens de diferentes espécies, com impactos na saúde pública e animal. Visando contribuir para o entendimento e prevenção das rotaviroses assim como suas possíveis relações zoonóticas, caracterizou-se os 11 segmentos de dsRNA de rotavírus codificadores das proteínas estruturais e não estruturais presentes em amostras fecais positivas de suínos coletadas nos anos de 2012-2013, em 2 estados brasileiros. Mediante o emprego de RT-PCR, sequenciamento nucleotídico e análises filogenéticas, todos os segmentos genéticos oriundos de 12 amostras de RVA detectados em suínos foram analisados e comparados com os de outras amostras descritas previamente. As sequências obtidas para os genes codificadores das proteínas NSP2, NSP3 e VP6 contemplaram a open reading frame (ORF) completa do gene, enquanto que a ORF parcial foi determinada para os genes codificadores das proteínas VP1, VP2, VP3, VP4, VP7, NSP1, NSP4, NSP5 e NSP6. Os genotipos de rotavírus suíno provenientes das regiões amostradas concordam com os mais frequentemente descritos nesta espécie animal, apresentando, assim, uma matriz genética suína com a maioria dos segmentos pertencentes à constelação genotípica 1, com exceção dos genes codificadores das proteínas VP6 e NSP1, os quais foram os genotipos I5 e A8, respectivamente. Apesar de predominar o genotipo 1 (Wa-like) nas sequências deste estudo, a análise genômica sugere a existência de uma variação intragenotípica no genoma do rotavírus do grupo A atualmente circulante nas populações suína amostradas dos estados de São Paulo e Mato Grosso. Adicionalmente, buscou-se identificar os aminoácidos relacionados com a adaptação dos rotavírus no hospedeiro e assinaturas genéticas que distinguissem RVA suíno e humano. Para isso, as sequências obtidas neste estudo foram comparadas com outras cepas de RVA detectadas nestas duas espécies e pertencentes ao genotipo 1 (Wa-like) disponíveis no Genbank. Como resultados foram encontrados mais de 75 sítios de mudanças deaminoácidos que diferenciam RVA suíno e humano além de sítios de substituiçãopresentes em algumas proteínas virais que frequentemente covariaram entre elas. Estes resultados proporcionam um maior entendimento da diversidade viral circulante em unidades de produção suína e uma melhor compreensão dos animaiscomo reservatórios genéticos de cepas de rotavírus emergentes em humanos. / Group A rotaviruses (RVA) are leading causes of viral diarrhea in children and in the young of many animals species with impacts on public and animal health. To contribute to the understanding and prevention of rotaviruses as well as its possible zoonotic relationships, it was characterized the 11 segments of dsRNA rotavirus encoding the structural and nonstructural proteins present in positive fecal samples from pigs collected in the years 2012-2013 in 2 Brazilian states. Using RT-PCR, nucleotide sequencing, and phylogenetic analyses, all gene segments from 12 RVA samples detected in pigs were analyzed and compared with the other samples as described previously. The sequences obtained for the NSP2, NSP3, and VP6 coding genes covered the complete open reading frame (ORF), while the partial ORF was determined for the VP1, VP2, VP3, VP4, VP7, NSP1, NSP4, NSP5 and NSP6 coding genes. The genotypes of porcine rotavirus from the sampled regions agree with the most frequently reported in this species, presenting thus a porcine-RVA-like backbone with most segments being designated as constellation genotype 1, with the exception of the VP6 and NSP1 coding genes, which were genotypes I5 and A8, respectively. Although genotype 1 (Wa-like) sequences were predominant in this study, the genomic analysis suggests the existence of a intragenotypic variation in group A rotavirus genome currently circulating in swine populations sampled in the states of São Paulo and Mato Grosso. In addition, we sought to identify the amino acids related to the adaptation of rotavirus in the host and genetic signatures that distinguish RVA pig and human. For this, the sequences obtained in this study were compared with other strains of RVA detected in these two species, belonging to genotype 1 (Wa-like) available in Genbank. The following results were found more than 75 sites of amino acid changes that differentiate RVA pig and human as well as substitution sites present in some viral proteins that often covaried between them. These results provide a greater understanding of the current viral diversity in swine production units and a better understanding of animals as genetic reservoirs emerging rotavirus strains in humans.

A tese aborda os modos de composição e caracterização das personagens nos romances Ressurreição (1872), Helena (1876) e Dom Casmurro (1899), de Machado de Assis, considerando seus aspectos relacionais. A partir da crítica e correspondência de autoria do escritor nas décadas de 1860 e 1870, mapeamos como ele concebe e analisa a questão da personagem de ficção. Machado de Assis prioriza a personagem em seus textos críticos, tendendo a analisá-la pelos critérios dos caracteres e dos sentimentos. Os caracteres são um costume retórico que visa ao desenho de tipos, remontando a Teofrasto (séc. VI a.C.) e a uma rede de letrados como os satiristas ingleses dos séculos 16 e 17 e La Bruyère (séc. 17). Por um lado, Machado mobiliza essa técnica para a concepção das personagens. Por outro lado, notamos a ironia no procedimento, dada a sua contradição com a figuração dos sentimentos e a diferença implicada no recuo temporal às letras antigas. A partir desse problema de tensão que concerne à personagem machadiana, analiso a referência aos caracteres e retratos antigos e a figuração de um mundo imaginário, que recorre a processos psicanalíticos, enquanto eixos que atuam na composição e caracterização. De forma coerente com a defesa de Machado de Assis em sua própria crítica, nos romances abordados as personagens são compostas de maneira contextual, relacionando-se com a estrutura da trama e com seu meio social no universo narrativo. Ou seja, com a sua constelação de personagens. Observamos que Félix, Estácio e Bento/Santiago/Casmurro/Dom Casmurro organizam em torno de si suas respectivas constelações de personagens, de forma hierárquica. No entanto, eles compõem heróis falhados para esses grupos, agindo não apenas para a própria aniquilação, como também para a anulação dos demais. Especialmente, eles se desenvolvem por meio de enganos e autoenganos quanto a serem excluídos e traídos pelo par amoroso. Assim, a constelação de personagens desses romances machadianos Ressurreição, Helena e Dom Casmurro arranja-se, igualmente, por referência à organização social da família brasileira patriarcal, que persiste no oitocentos, bem como às dinâmicas de ciúme e inveja sistematizadas pela teoria psicanalítica. Ao considerar a trajetória de Ressurreição, Helena e Dom Casmurro, visualizou-se um processo de complexidade crescente na composição e caracterização das personagens, conforme a exploração de alguns temas-chave e a experimentação no âmbito de suas constelações. / This dissertation approaches characters composition and characterization in Machado de Assis novels Resurrection (1872), Helena (1876), and Dom Casmurro (1899) by considering characters relational aspects. We map how Machado de Assis perceives characters in his own critics and letters from the 1860s and the 1870s. The writer stresses the issue of characters as he analyzes them by the criteria of Theophrastian characters and of emotions. The Theophrastian character is a rhetorical genre for drawing types. It goes back to Theophrastus (IV BC) and to a network that includes English Theophrastian character books (16th and 17th centuries), La Bruyère (17th century), among others. On one hand, Machado evokes this technique for characters composition and characterization. On the other hand, theres an irony to this stylistic gesture for its chronological misplacement. Moreover, for the eventual contradiction between Theophrastian characters and the picturing of particular emotions. With this tension in mind, I analyze Machadian characters references to Theophrastian characters and to old portraits, as well as the imagination of these figures according to the literary figuration of psychoanalytical processes. Both orientations take part in the composition of Machados characters. In a coherent relation with the writers own critical essays, in the novels here approached characters are connected to their plots and societies. This means that their composition is entangled with their character constellation. We observe that Félix, Estácio, Bento/Santiago/Casmurro/Dom Casmurro constitute the central reference for their respective character constellation in a hierarchical way. Nonetheless, they prove to be fail heroes for their groups. Not only do they act for self-destruction, but also for the annihilation of others. Thus, each character constellation in these three novels Resurrection, Helena, and Dom Casmurro is equally arranged in relation with references to the Brazilian patriarchal family that remains in the eighteenth century, and to the dynamics of jealousy and envy systemized by psychoanalytic theories. By considering the trajectory of Resurrection, Helena, and Dom Casmurro, we have viewed a process of growing complexity in Machadian characters composition and characterization, which is developed from the exploration of key narrative themes and from the literary experimentation concerning character constellations.

A tese aborda os modos de composição e caracterização das personagens nos romances Ressurreição (1872), Helena (1876) e Dom Casmurro (1899), de Machado de Assis, considerando seus aspectos relacionais. A partir da crítica e correspondência de autoria do escritor nas décadas de 1860 e 1870, mapeamos como ele concebe e analisa a questão da personagem de ficção. Machado de Assis prioriza a personagem em seus textos críticos, tendendo a analisá-la pelos critérios dos caracteres e dos sentimentos. Os caracteres são um costume retórico que visa ao desenho de tipos, remontando a Teofrasto (séc. VI a.C.) e a uma rede de letrados como os satiristas ingleses dos séculos 16 e 17 e La Bruyère (séc. 17). Por um lado, Machado mobiliza essa técnica para a concepção das personagens. Por outro lado, notamos a ironia no procedimento, dada a sua contradição com a figuração dos sentimentos e a diferença implicada no recuo temporal às letras antigas. A partir desse problema de tensão que concerne à personagem machadiana, analiso a referência aos caracteres e retratos antigos e a figuração de um mundo imaginário, que recorre a processos psicanalíticos, enquanto eixos que atuam na composição e caracterização. De forma coerente com a defesa de Machado de Assis em sua própria crítica, nos romances abordados as personagens são compostas de maneira contextual, relacionando-se com a estrutura da trama e com seu meio social no universo narrativo. Ou seja, com a sua constelação de personagens. Observamos que Félix, Estácio e Bento/Santiago/Casmurro/Dom Casmurro organizam em torno de si suas respectivas constelações de personagens, de forma hierárquica. No entanto, eles compõem heróis falhados para esses grupos, agindo não apenas para a própria aniquilação, como também para a anulação dos demais. Especialmente, eles se desenvolvem por meio de enganos e autoenganos quanto a serem excluídos e traídos pelo par amoroso. Assim, a constelação de personagens desses romances machadianos Ressurreição, Helena e Dom Casmurro arranja-se, igualmente, por referência à organização social da família brasileira patriarcal, que persiste no oitocentos, bem como às dinâmicas de ciúme e inveja sistematizadas pela teoria psicanalítica. Ao considerar a trajetória de Ressurreição, Helena e Dom Casmurro, visualizou-se um processo de complexidade crescente na composição e caracterização das personagens, conforme a exploração de alguns temas-chave e a experimentação no âmbito de suas constelações. / This dissertation approaches characters composition and characterization in Machado de Assis novels Resurrection (1872), Helena (1876), and Dom Casmurro (1899) by considering characters relational aspects. We map how Machado de Assis perceives characters in his own critics and letters from the 1860s and the 1870s. The writer stresses the issue of characters as he analyzes them by the criteria of Theophrastian characters and of emotions. The Theophrastian character is a rhetorical genre for drawing types. It goes back to Theophrastus (IV BC) and to a network that includes English Theophrastian character books (16th and 17th centuries), La Bruyère (17th century), among others. On one hand, Machado evokes this technique for characters composition and characterization. On the other hand, theres an irony to this stylistic gesture for its chronological misplacement. Moreover, for the eventual contradiction between Theophrastian characters and the picturing of particular emotions. With this tension in mind, I analyze Machadian characters references to Theophrastian characters and to old portraits, as well as the imagination of these figures according to the literary figuration of psychoanalytical processes. Both orientations take part in the composition of Machados characters. In a coherent relation with the writers own critical essays, in the novels here approached characters are connected to their plots and societies. This means that their composition is entangled with their character constellation. We observe that Félix, Estácio, Bento/Santiago/Casmurro/Dom Casmurro constitute the central reference for their respective character constellation in a hierarchical way. Nonetheless, they prove to be fail heroes for their groups. Not only do they act for self-destruction, but also for the annihilation of others. Thus, each character constellation in these three novels Resurrection, Helena, and Dom Casmurro is equally arranged in relation with references to the Brazilian patriarchal family that remains in the eighteenth century, and to the dynamics of jealousy and envy systemized by psychoanalytic theories. By considering the trajectory of Resurrection, Helena, and Dom Casmurro, we have viewed a process of growing complexity in Machadian characters composition and characterization, which is developed from the exploration of key narrative themes and from the literary experimentation concerning character constellations.

Dissertation (Ph. D.)--University of Stellenbosch, 1997. / Bibliography. Also available via the Internet

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High peak-to-average power ratio (PAPR) is a serious drawback in orthogonal frequency division multiplexing (OFDM) systems. Various methods have been proposed to reduce PAPR, active constellation extension (ACE) scheme has excellent performance. There are two schemes were proposed in traditional ACE, the one of which is ACE-Smart Gradient-Project (SGP) which can significantly reduce PAPR through first iteration. In fact, optimal solution is not obtained in ACE-SGP, we find the scheme can be formulated as convex optimization problem, that is, we can find out optimal solution to minimize PAPR by convex optimization algorithm. Two proposed schemes are based on two low complexity schemes, respectively, and they were proved to satisfy convex optimization problem. Although the power of transmission and complexity of optimization algorithm in the proposed schemes are higher than that of the traditional ACE-SGP scheme, but proposed schemes has proper improvement in PAPR reduction.

In this thesis, we propose and evaluate quasi-optimal algorithms for solving the code-constellation optimization problem in M-ary CDMA system. The M-ary CDMA system is a new CDMA architecture. The more spreading codes used in each user, and the higher bandwidth efficiency can achieve with more bits packed in each symbol. We use a code, which we refer to as ¡§mapping code¡¨, to help form a multidimensional spherical code-constellation. The M codewords of the mapping code correspond one-to-one to the M points on the code-constellation. Thus, the code-constellation optimization problem is a combinatorial optimization problem. We present that an exhaustive search (ES) algorithm would have compute and check all possible subset, and then this problem becomes a NP-hard. Based on the exhaustive search algorithm, we propose symmetric points search (SPS) algorithm to reduce computation complexity, but it is not optimal algorithm. In addition, we propose a quasi-optimal algorithm, namely Manhattan distance search (MDS) algorithm. Numerical results and comparisons are provided to illustrate that the computation complexity of the Manhattan distance search algorithm increases linearly with dimension of code-constellation and its performance is better than others.