Dissertations / Theses on the topic 'Position coding'

La localisation des objets dans l'espace est l'une des fonctions centrales du système visuel. Lorsqu'un observateur ou une cible se déplace, le mouvement de l’œil ou de l'objet peut être pris en compte pour calculer la position de l'objet à n'importe quel moment. Il a été démontré à plusieurs reprises que le mouvement visuel peut fortement influencer la position perçue d'un objet. Par exemple, la position d'un stimulus contenant une texture en mouvement (De Valois & De Valois, 1991; Ramachandran & Anstis, 1990), celle d'un flash présenté sur (Cavanagh & Anstis, 2013) ou à côté (Whitney & Cavanagh, 2000) d'une texture en mouvement, et même les positions d'apparition et de disparition d'objets en mouvement (Fröhlich, 1923) sont perçus comme étant déplacées dans le sens du mouvement. Dans le cadre de cette thèse, nous avons exploré la relation entre ces changements de position provoqués par le mouvement et différentes formes d'attention visuelle: 1) l'attention spatiale temporaire, 2) l'attention globale et locale, 3) l'attention spatiale maintenue, et 4) l'attention centrée sur les objets. Dans une première série d'expériences, nous avons étudié dans quelle mesure et de quelle manière l'attention module l'effet Fröhlich (i.e la position perçue du début du mouvement est déplacée dans le sens du mouvement). Dans les expériences 1 et 2, nous avons mesuré l'effet Fröhlich dans différentes conditions de d'indiçage et nous avons montré que les indices non valides ou tardifs entraînent des déplacements perceptifs plus importants. Dans l'expérience 3, nous avons comparé les déplacements provoqués par le mouvement lorsque les sujets portaient leur attention sur un ensemble d'objets en mouvement qui formaient un groupe à quand ils portaient leur attention à un seul stimulus parmi cet ensemble. Les résultats montrent que l'effet Fröhlich n'était présent que lorsque l'attention sélectionne un seul objet et qu'il disparaît lorsque le stimulus est perçu dans un contexte de groupe (global). Ainsi, ces résultats suggèrent que l'attention sélective est à la fois à l'origine de et module l'effet Fröhlich. Ayant établi que les délais temporels de l'attention augmentent les changements de la position provoqués par le mouvement, l'étude suivante était conçue pour explorer si la distribution spatiale de l'attention a le même effet. Dans cette étude, nous avons utilisé le « flash grab » - un changement de position illusoire aperçu quand une cible est brièvement présentée brièvement sur un fond en mouvement au moment de l'inversion du sens du mouvement (Cavanagh & Anstis, 2013). Les essais étaient regroupés en différents blocks au début desquels un indice indiquait la région de l'espace dans laquelle la cible était susceptible d'apparaître. Nos résultats mettent en évidence une diminution du flash-grab quand la distribution spatiale des cibles était limitée à une plage de 90° ou moins. Dans la dernière étude, nous nous sommes demandés si l'effet du mouvement sur la position perçue affecte l'objet dans son ensemble ou si il affecte les caractéristiques distinctes d'un même objet indépendamment les uns des autres. Pour cela nous avons utilisé le paradigme flash grab en présentant brièvement une forme sur un fond en mouvement au moment de l'inversion du sens du mouvement. Les résultats indiquent que les attributs de la cible orthogonaux au mouvement du fond étaient déplacés, alors que les attributs parallèles au mouvement restaient intacts. Ceci suggère que le mouvement interagit avec la position des attributs de l'objet (et que l'attention focale sélectionne) avant que ces attributs ne soient regroupés en un objet. En conclusion, nous avons utilisé une variété de manipulations attentionnelles à des changements de position provoqués par le mouvement pour étudier le lien entre l'amplitude de l'illusion et les caractéristiques attentionnelles utilisé
Localizing objects in space is one of the central functions of the visual system. When an observer or a target is moving, the motion of the eye or the object can be taken into account to compute the current object locations. It has been shown many times that visual motion can strongly influence the perceived position of an object. For example, a stationary patch containing moving texture (De Valois & De Valois, 199; Ramachandran & Anstis, 1990), a flash presented on (Cavanagh & Anstis, 2013) or next to (Whitney & Cavanagh, 2000) a moving texture, and even the onset and offset positions of the moving targets (Fröhlich, 1923) are perceived as shifted in the direction of motion. In this thesis we explore the relationship between these motion-induced position shifts and visual attention in the following forms: 1) transient spatial attention, 2) global and local attention, 3) sustained spatial attention, and 4) object-based attention. In the first series of experiments we looked at whether and how attention modulates the shift in localization of motion onset (Fröhlich effect). In Experiments 1 and 2 we measured Fröhlich effect under different cueing conditions and established that invalid or late cues produced larger perceptual shifts. In Experiment 3 we compare the motion-induced shifts when the subjects attended to a set of moving stimuli as a group and when they attended to an orientation singleton. We showed that the Fröhlich effect was only present when the target was individuated and disappeared when the stimulus was perceived globally. Thus, the Fröhlich effect appeared to be both produced and modulated by focal attention. Having established that temporal delays of attention increase motion-induced position shifts, the next study explored if spatial distribution of attention has a similar effect. In this study we used flash grab - an illusory position shift seen when a target is briefly flashed on top of a moving background that abruptly changes direction (Cavanagh & Anstis, 2013). Trials were presented in blocks and before each block a cue indicated a range of possible target locations. We found that the flash grab was reduced if the spatial distribution of targets was limited to a range of 90° or less. The final study asked whether motion shifts the perceived position of an object as a whole or if separate features of a single object are shifted independently. To test this we used the flash grab paradigm and briefly presented a shape on top of a moving background at the moment it changed direction. The results showed that the features of the target that were orthogonal to the background motion were shifted, whereas the features parallel to the motion were intact. This suggests that motion interacts with the position of the object's features (and focal attention selects them) before they are bound together into an object. In conclusion, we applied a variety of attentional manipulations to motion-induced position shifts, and examined the link between the strength of the illusion and the characteristics of attention used in a particular task. We found that 1) motion-induced position shifts require focused attention and the possibility to track an individual motion trajectory; 2) allowing attention to be allocated more efficiently in space reduces the illusion; and 3) motion-induced shifts operate on the feature-based and not object-based level

The rapid and significant development of communications links between satellites has made it possible to use various applications such as relay voice, video, multimedia, etc. As a result, a great deal of research has been done in this field during the last few years to reduce power consumption and increase transmission reliability. This thesis is concerned with an analysis of intersatellite links in free space, with optical links using laser sources being considered in particular. It includes a literature survey and a thorough theoretical investigation into designing the model of the link in free space. This thesis describes the novel technique of designing the optical receiver that consists of PIN photodiode as a photodetector, Semiconductor optical amplifier (SOA) and a 3rd order Butterworth filter with central decision detection. In addition, it discusses the use of several different coding schemes for use in such links: multiple pulse position modulation (MPPM); digital pulse position modulation (DPPM); Dicode pulse position modulation (Dicode PPM). This novel technique of an optical receiver is investigated and new work is presented in order to examine the noise performance of this optical receiver and hence determine its sensitivity and the number of photons received for a specified error rate. Further new work is carried out to compare these coding schemes in terms of error weightings and coding efficiency through showing how the PCM error rate is affected by false alarm and erasure errors for MPPM, DPPM and Dicode PPM coding 3, 4, 5 and 6 bits of PCM. An original maximum likelihood sequence detector (MLSD) is presented in this thesis in order to perform these comparisons. In addition, computer simulations models (using MCAD) are performed to compare these three coding schemes operating with 3, 4, 5 and 6 bits of PCM in terms of sensitivity and bandwidth efficiency. These comparisons show that MPPM coding 3, 4, 5 and 6 bits of PCM is the appropriate coding scheme to be used in optical inter-satellite links in free space and PCM data rates of 1 Gbit/s.

Article shows presence of the imbalance caused by insufficient level of productivity of modern and perspective information communication technologies concerning information intensity of bit streams. It is described how imbalance level reducing can be formed as a result of increasing of information processing technologies efficiency and that JPEG platform is the basic concept for construction of technologies of compression representation. Therefore it is proposed to provide further development of video processing methods using individual components of the JPEG platform for improving the integrity of information in terms of ensuring the required level of its availability.:

Cette thèse est centralisée sur cette question : comment est-ce que le système visuel peut coder efficacement la position des objets en mouvement, en dépit des diverses sources d'incertitude ? Cette étude déploie une hypothèse sur la connaissance a priori de la cohérence temporelle du mouvement (Burgi et al 2000; Yuille and Grzywacz 1989). Nous avons ici étendu le cadre de modélisation précédemment proposé pour expliquer le problème de l'ouverture (Perrinet and Masson, 2012). C'est un cadre d'estimation de mouvement Bayésien mis en oeuvre par un filtrage particulaire, que l'on appelle la prévision basé sur le mouvement (MBP). Sur cette base, nous avons introduit une théorie du codage de position basée sur le mouvement, et étudié comment les mécanismes neuronaux codant la position instantanée de l'objet en mouvement pourraient être affectés par le signal de mouvement le long d'une trajectoire. Les résultats de cette thèse suggèrent que le codage de la position basé sur le mouvement peut constituer un calcul neuronal générique parmi toutes les étapes du système visuel. Cela peut en partie compenser les effets cumulatifs des délais neuronaux dans le codage de la position. En outre, il peut expliquer des changements de position basés sur le mouvement, comme par example, l'Effect de Saut de Flash. Comme un cas particulier, nous avons introduit le modèle de MBP diagonal et avons reproduit la réponse anticipée de populations de neurones dans l'aire cortical V1. Nos résultats indiquent qu'un codage en position efficace et robuste peut être fortement dépendant de l'intégration le long de la trajectoire
Coding the position of moving objects is an essential ability of the visual system in fulfilling precise and robust tracking tasks. This thesis is focalized upon this question: How does the visual system efficiently encode the position of moving objects, despite various sources of uncertainty? This study deploys the hypothesis that the visual systems uses prior knowledge on the temporal coherency of motion (Burgi et al 2000; Yuille and Grzywacz 1989). We implemented this prior by extending the modeling framework previously proposed to explain the aperture problem (Perrinet and Masson, 2012), so-called motion-based prediction (MBP). This model is a Bayesian motion estimation framework implemented by particle filtering. Based on that, we have introduced a theory on motion-based position coding, to investigate how neural mechanisms encoding the instantaneous position of moving objects might be affected by motion. Results of this thesis suggest that motion-based position coding might be a generic neural computation among all stages of the visual system. This mechanism might partially compensate the accumulative and restrictive effects of neural delays in position coding. Also it may account for motion-based position shifts as the flash lag effect. As a specific case, results of diagonal MBP model reproduced the anticipatory response of neural populations in the primary visual cortex of macaque monkey. Our results imply that an efficient and robust position coding might be highly dependent on trajectory integration and that it constitutes a key neural signature to study the more general problem of predictive coding in sensory areas

The ability to link a particular phenotype to its causative genotype is one of the most challenging objectives for biological research. Although the genetic code provides an explicit formula for determining the sequence of amino acid phenotypes produced by a given nucleotide sequence, identifying specific residues that are functionally important remains problematic. Many computational approaches have been developed that use patterns observed in DNA sequences to identify these critical sites. However, very few research studies have used empirical data to test whether these approaches are truly able to identify sites of interest.In most empirical studies, the actual protein function and selective pressures are unknown; thus it is difficult to assess whether computational approaches are correctly identifying critical sites. Here I present two studies that utilize well-characterized empirical systems to evaluate and compare the performance of several computational approaches. In both cases, the proteins under study have specific amino acid substitutions that are confirmed to alter protein function and expected to be constrained by natural selection. In chapter 2, I examine functional variants in angiopoietin-like protein 4 (ANGPTL4), a protein involved in regulating plasma triglyceride levels; loss-of-function variants in this gene are believed to decrease the risk of cardiovascular disease. I apply several computational approaches to identify functional variants, including phylogenetic approaches for detecting positive selection. In chapter 3, I investigate the emergence of drug-resistance in HIV-1 during the course of antiretroviral drug therapy. I compare the performance of eight selection detection methods in identifying drug-resistant mutations in 109 intrapatient datasets with HIV-1 sequences isolated at multiple timepoints throughout drug treatment.It is critical that we develop methods to detect positively selected sites. The ability to detect these sites in silico, without the need for expensive and time consuming assays, would be invaluable to researchers in evolutionary biology, human genetics, and medicine. Through the research presented in this thesis, I hope to provide insight into the strengths and weaknesses of current approaches, thereby facilitating future research towards the development and improvement of evolutionary models.

This is a longitudinal multilevel analysis using third party coded data of 15 couples therapy sessions to identify which therapist Emotion Focused Therapy interventions (Management of Couple's Interaction, Working with Primary Emotion, Managing Defensive Responses, Reframing the Problem in Terms of the Cycle, and Placing Emerging Emotions into the Cycle) influenced husband-to-wife and wife-to-husband exchanges of Positive Behaviors (warmth, prosocial behaviors, communication, assertiveness, and listening). A mixed effects model was used to examine within- and between-individual variability. Men and women were modeled separately. A series of two-level multilevel models of change were examined, where Time is Level 1 and Individual is Level 2. Results indicated no significant relationship between Management of the Couple's Interaction, Managing Defensive Responses, and Reframing the Problem in Terms of the Cycle with both wife-to-husband and husband-to-wife positive behavior. Findings demonstrated that 44.5% of the variance in wife-to-husband positive behaviors and 66.5% of the variance in husband-to-wife positive behaviors was accounted for by the therapist Working with Primary Emotion and Placing Emerging Emotions in the Cycle. Specifically, these therapist interventions were significantly and negatively related to wife-to-husband and husband-to-wife positive behaviors over time in therapy. Clinical implications and directions for future research will be discussed.

La génétique inverse est devenue une méthode clé pour la production de virus à ARN génétiquement modifiés et pour comprendre les propriétés cellulaires et biologiques des virus. Cependant les méthodes les plus fréquemment utilisées, basées sur le clonage de génomes viraux complets dans des plasmides, sont laborieuses et imprévisibles. La première partie de cette thèse présente des études sur la mise au point d'un nouveau système de génétique inverse, appelé méthode ISA (Amplicons-Sous génomique-Infectieux), qui permet la génération, en quelques jours, de virus infectieux sauvages et génétiquement modifiés appartenant à trois familles différentes de virus à ARN simple brin de polarité positive, avec une grande maîtrise des séquences virales. Dans la deuxième partie de cette thèse, nous avons appliqué pour la première fois à un arbovirus (CHIKV), le ré-encodage des codons - une méthode développée récemment et très excitante pour le développement de vaccins vivants atténués. En utilisant une approche aléatoire de ré-encodage des codons qui attribue au hasard des codons sur la base de la séquence en acides aminés correspondante, nous avons mis en évidence des pertes importantes de fitness réplicatif sur des cellules de primates et d'arthropodes. La diminution du fitness réplicatif est en corrélation avec le degré de ré-encodage, une observation qui peut aider à la modulation de l'atténuation virale. En utilisant l'expérience acquise avec le CHIKV, nous avons transposé avec succès ce mécanisme d'atténuation au JEV et amélioré notre maîtrise du processus d'atténuation en utilisant une combinaison de la synthèse de novo et de la méthode ISA
Reverse genetics has become a key methodology for producing genetically modified RNA viruses and deciphering cellular and viral biological properties, but the most commonly used methods, based on the preparation of plasmid-based complete viral genomes, are laborious and unpredictable. The first part of this thesis presents studies relating to the development of a new reverse genetics system, designated the ISA (Infectious-Subgenomic-Amplicons) method, which enabled the generation of both wild-type and genetically modified infectious viruses belonging to three different families of positive, single stranded RNA viruses within days with great control of the viral sequences. In the second part of this thesis, we applied for the first time to an arbovirus (CHIKV), codon re-encoding - a recently developed and very exciting method for the development of live attenuated vaccines. Using a random codon re-encoding approach which randomly attributed nucleotide codons based on their corresponding amino acid sequence, we identified major fitness losses of CHIKV in both primate and arthropod cells. The decrease of replicative fitness correlated with the extent of re-encoding, an observation that may assist in the modulation of viral attenuation. Detailed analysis of these observed replicative fitness losses indicated that they are the consequence of several independent re-encoding induced events. Using the experience acquired on the CHIKV, we successfully transposed this attenuation mechanism to JEV and improved our control of the attenuation process by using a combination of de novo synthesis and the ISA method

Le P-TEFb est un facteur positif de Mongation de la transcription par TARN polymérase IL C'est à ce jour le seul complexe cycline-CDK (Cycline T-CDK9) régulé par un ARN non codant. Le P-TEFb existe sous deux formes en équilibre dans la cellule : une petite forme active et une grande forme inactive, qui comprend en plus du P-TEFb, la protéine HEXIM et TARN non codant 7SK. Le 7SK modifierait la conformation de HEXIM et démasquerait son domaine d'interaction avec la Cycline T. Différents stimuli, comme une inhibition de la transcription, conduisent à la dissociation du grand complexe P-TEFb. Nous avons mis en évidence une nouvelle zone de contact direct entre HEXIM et la Cycline T par mutagenèse. L'interaction entre HEXIM et le P-TEFb existe bien dans les cellules. Elle est en effet détectable par des expériences de FRET et de couplage covalent. Ces expériences indiquent surtout l'existence d'un complexe, non décrit précédemment, entre HEXIM et le P-TEFb, qui se maintient lors d'un arrêt de la transcription. Par ailleurs, nous avons montré le recrutement des partenaires inhibiteurs du P-TEFb, HEXIM et 7SK, sur des sites de transcription, par des techniques de microscopie et des immunoprécipitations de la chromatine. HEXIM et 7SK pourraient ainsi contrôler l'activation spatiotemporelle du P-TEFb sur les sites de transcription
P-TEFb is a positive elongation factor for RNA polymerase II transcription. It is a unique example of a CDK-cyclin complex (CDK9-Cyclin T) regulated by a non-coding RNA. P-TEFb exists under two forms in equilibrium in the cell: a small active one, and a large inactive one, also containing the HEXIM protein and the 7SK non coding RNA. 7SK would change HEXIM conformation and unmask its domain of interaction with the cyclin subunit of P-TEFb. Many stimuli, as transcription inhibition, result in the dissociation of the large inactive P-TEFb complex. We characterized a new domain of HEXIM implicated in its direct contact with Cyclin T by mutagenesis. HEXIM and P-TEFb interact in the cell, as confirmed by FRET and crosslinking experiments. These experiments mainly showed a new HEXIM/P-TEFb complex, which resists to transcriptional arrest. We also demonstrate the recruitment of P-TEFb inhibitory partners, HEXIM and 7SK, on transcription sites, by microscopy and chromatin immunoprecipitation experiments. HEXIM and 7SK would thus control the spatio-temporal activation of P-TEFb on transcription sites

La somatostatine est un peptide de 14 acides aminés (SS-14) qui, en tant que neuromédiateur ou neurohormone exerce de multiples effets, aussi bien dans le cerveau que dans les organes périphériques. Initialement isolée chez les mammifères, la SS-14 a ensuite été retrouvée, sans modification de séquence, dans tous les groupes de vertébrés. Divers variants de somatostatine, issus de gènes distincts, ont été par ailleurs mis en évidence chez plusieurs espèces de poissons. Toutefois, chez les tétrapodes, il était généralement admis qu'il n'existait qu'un seul gène de somatostatine. A l'occasion du présent travail, nous remettons en cause cette conception en montrant l'existence chez la grenouille Rana ridibunda de deux gènes distincts de somatostatine. Le premier code la SS-14 classique (SS1), tandis que le second code le variant [Pro2, Met13]SS-14 (SS2). Par ailleurs, nous mettons en évidence, chez le dipneuste Protopterus annectens, l'équivalent du gène SS2, qui code pour un nouveau variant de séquence [Pro2]SS-14. Le caractère orthologue des SS2 de grenouille et de dipneuste s'appuie sur les observations suivantes : I) la présence dans la séquence des deux peptides d'un résidu proline en position 2 ; II) un taux de similitude relativement élevé entre les séquences de leurs précurseurs ; III) une expression de leurs gènes presque exclusivement limitée au système nerveux central, contrairement aux gènes de type SS1 qui sont également exprimés dans le pancréas et le tractus gastro-intestinal. L'existence d'un gène SS2 à la fois chez les amphibiens et chez les dipneustes montre que la duplication dont ce gène est issu est antérieure à l'émergence des tétrapodes. De telles conclusions sont confortées par la présence, récemment établie, d'une PSS2 chez les téléostéens. Par ailleurs, la découverte chez les mammifères de la cortistatine, un nouveau peptide visiblement apparenté à la SS2, montre que le gène de la PSS2 existe probablement chez tous les ostéichthyens.

Le beet necrotic yellow vein virus (BNYVV) est un phytovirus qui possède un génome segmenté à ARN de polarité positive. L’ARN3 viral renferme le domaine « core » qui contient une séquence de 20 nucléotides appelée « coremin », indispensable au mouvement systémique du virus chez Beta macrocarpa. L’ARN3 subit un processus de dégradation qui conduit à la formation d’un ARN non codant (ncRNA3) correspondant à son extrémité 3’. Ce dernier est stabilisé par la séquence « coremin » à son extrémité 5’. Grâce à l’outil génétique levure, l’exoribonucléase Xrn1 puis l’exoribonucléase XRN4 de plante ont été identifiées comme étant responsable de l’accumulation du ncRNA3 à partir d’ARN3. Nous avons démontré in vitro que l’accumulation de ncRNA3 est liée au blocage de Xrn1 par « coremin ». La protéine virale p14, un suppresseur du RNA silencing codée par l’ARN2, est aussi nécessaire au mouvement systémique du virus et interagit avec la séquence « coremin ». Nos travaux confirment que l’ARN3 est capable de complémenter partiellement un mutant allélique de p14 dans l’infection locale et systémique. Nos résultats mettent en évidence un effet de la protéine p14 sur la systémie du RNA silencing et sur une éventuelle cible cellulaire RDR6
The beet necrotic yellow vein virus (BNYVV) is a multipartite positive-stranded RNA phytovirus. The RNA3 contains a « core » sequence in which resides the « coremin » motif of 20 nucleotides absolutely required for the viral systemic movement in Beta macrocarpa. The RNA3 undergoes a process that produces a noncoding RNA3 (ncRNA3), stabilized by « coremin » at its 5’ end. Using a yeast genetic approach, the exoribonuclease Xrn1 and plant XRN4 have been identified as being responsible for the ncRNA3 accumulation from RNA3 processing. In vitro, we showed that the ncRNA3 accumulation is due to the stalling of Xrn1 by “coremin”. The viral p14 protein, an RNA silencing suppressor encoded by the RNA2, is also required for the systemic movement and interacts with the “coremin” sequence. Our studies demonstrated the ability of RNA3 to partially complement an allelic p14 mutant in local and systemic infections. Our data highlighted an effect of the p14 protein on the RNA silencing movement and on the potential cellular target RDR6

La presente tesi ha come obiettivo analisare il concetto e le specie di squilibrio eccessivo della relazione giuridica di consumo, nonché la possibilitá di correzione di una delle specie di squilibrio eccessivo – l’esercizio abusivo della posizione giuridica dei fornitori – per mezzo della clausola generale di divieto di vantaggio eccessivo, previsto nel Codice di Difesa del Consumatore (Art. 39, V c/c art. 51, IV e §1°). Si tratta, in essenza, di uno studio sulla stessa relazione giuridica di consumo, ragione per la quale si impone, inizialmente, un’analisi con riferimento ai suoi pressuposti fatico-normativi, elementi costitutivi e caratteristica fondamentale (Parte I, Capitolo1) per, soltanto dopo, affrontare il tema degli “squilibri” (strutturale e eccessivo) esistenti in questo tipo di relazione giuridica (Parte I, Capitolo 2), quando si cerca di dimostrare che lo squilibrio eccessivo non si confonda con lo squilibrio strutturale (intrinseco), nella misura in cui questo è realtà costitutiva della stessa relazione giuridica di consumo, essendo, per questo, riconosciuta e tollerabile dal dirito; invece, lo squilibrio eccessivo è realtà che supera i limiti del “giuridicamente tollerabile” – cioè, dello stato di squilibrio strutturale – e, per questo motivo, necessita di essere correta da un mezzo dell’ordine giuridica ( nel caso brasiliano, dal sistema giuridico di protezione e difesa dei consumatori, centralizzato nei valori e norme costituzionali e sistematizzato nel Codice di Difesa del Consumatore – Legge n. 8.078, dell’11 settembre 1990). E per la correzione delle situazioni di squilibrio eccessivo della relazione di consumo generate dall’esercizio abusivo della posizione giuridica dei fornitori il legislatore brasiliano, attento alla necessità di comprensione del diritto privato come un sistema giuridico aperto (Parte II, Capitolo 3) ha costruito il Codice di Difesa del Consumatore come uno microsistema dotato di norme casistiche e di norme aperte (le cosidette “clausole generali”), distacandosi, tra loro, la clausola generale di divieto di vantaggio eccessivo, che si intende essere la “clausola fondamentale di correzione dell’abuso nelle relazioni giuridiche di consumo” (Parte II, Capitolo 4), allo stesso tempo in cui suo ambito di applicazione, fissato dallo stesso leggislatore (CDC, art. 51,§1º), contiene, dovuto alla sua grande generalità, l’ambito delle altre clausole generali di correzione e abuso, così come quelle di funzione sociale ed economica del diritto, buona-fede obiettiva, buone abitudine e lesione enorme, tutelando, infine, la globalità dei legittimi interessi dei consumatori – cioè, i loro interessi di natura patrimoniale e esistenziale – danneggiati dalla attuazione abusiva dei fornitori nel mercato di consumo.
A presente tese tem por objetivo analisar o conceito e as espécies de desequilíbrio excessivo da relação jurídica de consumo, bem como a possibilidade de correção de uma das espécies de desequilíbrio excessivo – o exercício abusivo de posição jurídica dos fornecedores – por meio da cláusula geral de proibição de vantagem excessiva, prevista no Código de Defesa do Consumidor (Art. 39, V c/c art. 51, IV e §1º). Trata-se, em essência, de um estudo sobre a própria relação jurídica de consumo, razão pela qual se impõe, inicialmente, uma análise acerca de seus pressupostos fático-normativos, elementos constitutivos e característica fundamental (Parte I, Capítulo 1) para, só então, enfrentar o tema dos “desequilíbrios” (estrutural e excessivo) existentes nesse tipo de relação jurídica (Parte I, Capítulo 2), quando se busca demonstrar que o desequilíbrio excessivo não se confunde com o desequilíbrio estrutural (intrínseco), na medida em que este é realidade constitutiva da própria relação jurídica de consumo, sendo, por isso mesmo, reconhecida e tolerável pelo direito; ao contrário, o desequilíbrio excessivo é realidade que ultrapassa os limites do “juridicamente tolerável” – isto é, do estado de desequilíbrio estrutural - e, por este motivo, precisa ser corrigida por meio da ordem jurídica (no caso brasileiro, pelo sistema jurídico de proteção e defesa dos consumidores, centralizado nos valores e normas constitucionais e sistematizado no Código de Defesa do Consumidor – Lei n. 8.078, de 11 de setembro de 1990). E para a correção das situações de desequilíbrio excessivo da relação de consumo geradas pelo exercício abusivo da posição jurídica dos fornecedores o legislador brasileiro, atento à necessidade de compreensão do direito privado como um sistema jurídico aberto (Parte II, Capítulo 3) construiu o Código de Defesa do Consumidor como um microsssistema dotado de normas casuísticas e de normas abertas (as chamadas “cláusulas gerais”), destacando-se, quanto a estas, a cláusula geral de probição de vantagem excessiva, que se entende ser a “cláusula fundamental de correção do abuso nas relações jurídicas de consumo” (Parte II, Capítulo 4), na medida em que seu âmbito de aplicação, fixado pelo próprio legislador (CDC, art. 51, §1º), abarca, por sua grande generalidade, o âmbito das demais cláusulas gerais de correção do abuso, como as de função social e econômica do direito, boa-fé objetiva, bons costumes e lesão enorme, tutelando, enfim, a globalidade dos legítimos interesses dos consumidores – isto é, seus interesses de natureza patrimonial e existencial – lesados pela atuação abusiva dos fornecedores no mercado de consumo.
The present thesis aims to analyze the concept and the species of excessive unbalance of the legal consumption relationship, as well as the possibility of correction of one of the species of excessive unbalance – the abusive use of the legal position of the suppliers – by the inclusion of the general clause of prohibition of unfair advantage, set out in the Consumer Defense Code (Art. 39, V c/c art. 51, IV and §1º). It is, essentially, a study on the legal consumption relationship itself, a reason for which it is imposed, initially, an analysis concerning its phaticnormative presumptions, constitutive elements and key characteristic (Part I, Chapter 1) for, only then, face the topic of “imbalances” (structural and excessive) existing in this type of legal relationship (Part I, Chapter 2), when willing to demonstrate that the excessive imbalance is not confounded with the structural imbalance (intrinsic), inasmuch as this is a constitutive reality of the legal consumption relationship itself, being, therefore, acknowledged and bearable by the law; on the contrary, the excessive imbalance is a reality which overcomes the limits of the “legally bearable” – that is, the structural imbalance status - and, for this reason, it has to be corrected by the law (in the Brazilian case, by the legal system of protection and defense of consumers, centered in the values and constitutional norms e ordered in the Consumer Defense Code – Law n. 8.078, from September 11th, 1990). And for the correction of excessive imbalance situations in the consumption relationship caused by the abusive practice of the legal position of the suppliers, the Brazilian legislator, attentive to the need of understanding of the private law as an open legal system (Part II, Chapter 3) created the Consumer Defense Code as a microsystem with cauistic norms and open norms (the so-called “general clauses”), highlighting, concerning these, the general clause of prohibition of unfair advantage, which is understood as the “key clause of abuse correction in the consumption legal relationships” (Part II, Chapter 4), inasmuch as in its scope of application, set by the legislator (CDC, art. 51, §1º), embraces, due to all things considered, the scope of the other general clauses of abuse correction, such as the law social and economic function, bona fide intentions, good manners and serious harm, tutoring, then, the whole of legitimate interests of the consumers – that is, their interests of property and existential nature – harmed by the abusive practice of suppliers in the consumer market.

La tesis se encarga de analizar, por un lado, la integración y el desarrollo de las nuevas tecnologías en la Administración de Justicia; y, por otro, los parámetros que constituyen la validez y eficacia del documento electrónico.
La primera cuestión se centra en la configuración de los Sistemas de Información de la Oficina Judicial y del Ministerio Fiscal, así como de la informatización de los Registros Civiles, donde el art. 230 LOPJ es la pieza clave. Se estudian sus programas, aplicaciones, la videoconferencia, los ficheros judiciales y las redes de telecomunicaciones que poseen la cobertura de la firma electrónica reconocida, donde cobran gran relevancia los convenios de colaboración tecnológica. La digitalización de las vistas quizá sea una de las cuestiones con más trascendencia, teniendo en cuenta que el juicio es el acto que culmina el proceso. Aunque no todos los proyectos adoptados en el ámbito de la e.justicia se han desarrollado de forma integral, ni han llegado a la totalidad de los órganos judiciales. El objetivo final es lograr una Justicia más ágil y de calidad, a lo cual aspira el Plan Estratégico de Modernización de la Justicia 2009-2012 aprobado recientemente.
En referencia a la segunda perspectiva, no cabe duda que el Ordenamiento jurídico y los tribunales, en el ámbito de la justicia material, otorgan plena validez y eficacia al documento electrónico. Nuestra línea de investigación se justifica porque cada vez son más los procesos que incorporan soportes electrónicos de todo tipo, ya sea al plantearse la acción o posteriormente como medio de prueba (art. 299.2 LEC). Entre otros temas examinamos el documento informático, la problemática que rodea al fax, los sistemas de videograbación y el contrato electrónico.
La tesi s'encarrega d'analitzar, per una part, la integració i el desenvolupament de les noves tecnologies dins l´Administració de Justícia; i, per l'altra, els paràmetres que constitueixen la validesa i l'eficàcia del document electrònic.
La primera qüestió es centra en la configuració dels Sistemes d´Informació de l´Oficina Judicial i del Ministeri Fiscal, així com de la informatització dels Registres Civils, on l'art. 230 LOPJ es la peça clau. S'estudien els seus programes, aplicacions, la videoconferència, el fitxers judicials i les xarxes de telecomunicacions que tenen la cobertura de la firma electrònica reconeguda, on cobren gran rellevància els convenis de col·laboració tecnològica. La digitalització de les vistes tal vegada sigui una de les qüestions amb més transcendència, tenint amb compte que el judici es l'acte que culmina el procés. Però no tots el projectes adoptats en l'àmbit de la e.justicia s'han desenvolupat d'una manera integral ni han arribat a la totalitat dels òrgans judicials. L'objectiu final es assolir una Justícia més àgil i de qualitat, al que aspira el Pla Estratègic de Modernització de la Justícia 2009-2012 aprovat recentment.
En referència a la segona perspectiva, no hi ha dubte que l´Ordenament jurídic i els tribunals, en l'àmbit de la justícia material, donen plena validesa i eficàcia al document electrònic. La nostra línia d'investigació es justifica perquè cada vegada son més el processos que incorporen suports electrònics de tot tipus, ja sigui quant es planteja l'acció o posteriorment como a medi de prova (art. 299.2 LEC). Entre altres temes examinem el document informàtic, la problemàtica que envolta al fax, els sistemes de videogravació i el contracte electrònic.
The thesis seeks to analyse, on the one hand, the integration and development of the new technologies in the Administration of Justice; and, on the other, the parameters which constitute the validity and efficiency of the electronic document.
The first question centres on the configuration of the Information Systems of the Judicial Office and the Public Prosecutor, as well as the computerisation of the Civil Registers, where the art. 230 LOPJ it's the part key. Their programmes, applications, the Video Conferencing, the judicial registers and the telecommunication networks which are covered by the recognised electronic signatures, are studied, where the agreements on technological collaboration gain great relevance. The digitalisation of evidence might perhaps be one of the questions with most consequence, bearing in mind that the judgment is the act by which the process is culminated. Although not all the projects adopted within the compass of e.justice have developed completely nor have reached all the judicial organs. The final objective is to achieve an agile, quality Justice, to which the recently approved Strategic Plan for the Modernisation of Justice aspires.
With reference to the second perspective, there is no doubt that the juridical Ordinance and the tribunals within the compass of material justice grant full validity and efficacy to the electronic document. Our line of investigation is justified because there are more and more processes which are sustained by electronic supports of all kinds, whether it be at the establishment of the action or later, as a proof of it (art. 299.2 LEC). Amongst other things, we examine the computerised document, the problems which surround the fax, the systems for video recording and the electronic contract.

碩士
國立臺灣大學
心理學研究所
103
Electrophysiological evidence suggests that the visual cortical neurons encode disparity through either position or phase difference between left and right receptive fields. Since Anzai, Ohzawa, & Freeman (1999a) proposed that the visual cortical neurons encode binocular disparity mainly rely on the receptive fields phase difference but less position difference, how group of neurons encode binocular disparity remains unclear. Here, we investigated the position disparity model at the population level with fMRI. Retinotopic BOLD activations were measured under binocular and two monocular (the left and right eye) viewing conditions with low contrast checkerboard patterns and fitted to a population receptive field (pRF) model (Dumoulin & Wandell, 2008). The position disparity was measured by the distance between centers of left and right pRFs. Also, a bootstrap method was used to generate simulated data to estimate variations of pRFs of each viewing condition of each voxel. This allows us to test binocular disparity of each neural population statistically. Our results showed that distributions of horizontal and vertical disparities of visual cortical neurons do not significant deviate from zero, suggesting that visual system does not prefer to any disparity. Moreover, simulations showed that a bunch of binocular voxels (30% on average) have a significant pRFs position shift (at α =.01 level), suggesting a position coding of disparity at the population level. Also, both horizontal and vertical disparities increase with the eccentricity in all visual cortices, which consistent with psychophysics’ results that the fusion limit is positive correlate to the eccentricity. Together, our results revealed (A) a position coding of binocular disparity and (B) neural evidence for increasing fusion limit with the eccentricity at the population level.

碩士
國立雲林科技大學
機械工程系碩士班
97
The pneumatic control system is a highly non-linear and time-varying system. The system parameters would be changed by compressible gas, friction force, external interference. The pneumatic control system has the advantage of easy to get energy and maintain, Therefore nowadays it could widely be applied in industry. In this paper, a new Full-Digital Flow Control Unit (DFCU) consisting of several parallel-connected 2/2 on-off valves is designed. The basic operation principle of the developed DFCU is described briefly as follows. If the demanded volumetric flow is quite low, then only few on-off valves will be energized to supply low amount of pneumatic power to the system. On the other hand, if the positioning system demands large amount of pneumatic power, then more 2/2 on-off valves will be switched to ON position. This means that DFCU could use switch valve''s number to achieve the proportional control. In this study, the software LABVIEW is utilized to develop the control system. At feedback parts will utilize the laser or linear wire potentiometer to be the sensor of the experiment. Then, this paper will utilize four kinds of coding scheme, such as PNM coding (Pulse Number Modulation) and Binary coding. Moreover, Based on these two coding scheme, this paper proposes two novel coding schemes. The first coding is Mixed PNM-Binary coding, it tries to combine good characteristics binary and PNM coding. The second one is mixed coding scheme based on PNM . We use PID and Fuzzy controller to control number of the actuated on-off valves. At last the position control is accomplish. Besides, the DFCU has advantage of simple structure, low cost, noise reduction and long life. It expect to popularize in business in the future.

Multipulse pulse position modulation (MPPM) has been widely proposed to improve data rate over the traditional pulse position modulation (PPM) in free-space optical communication systems. However, there is no known efficient method of encoding MPPM codewords. Furthermore, MPPM is not the optimal coding scheme (in terms of data rate) given the two main constraints of optical systems (duty cycle and zero runlength). In this work, an improved encoding technique for MPPM is provided as well as an analysis of regions where significant rate gain over MPPM is achievable. A new coding technique based on constrained coding is introduced that allows construction of codes which achieves considerable rate gain over comparable MPPM systems. In addition, our new codes allow for convenient concatenation with an outer-code and are suitable for iterative decoding. Simulation results show that these codes can achieve a $6$ dB coding gain over comparable MPPM systems.

No
Motion is known to distort visual space, producing illusory mislocalizations for flashed objects. Previously, it has been shown that when a stationary bar is flashed in the proximity of a moving stimulus, the position of the flashed bar appears to be shifted in the direction of nearby motion. A model consisting of predictive projections from the sub-system that processes motion information onto the sub-system that processes position information can explain this illusory position shift of a stationary flashed bar in the direction of motion. Based on this model of motion¿position interactions, we predict that the perceived position of a flashed stimulus should also be attracted towards a nearby moving stimulus. In the first experiment, observers judged the perceived vertical position of a flash with respect to two horizontally moving dots of unequal contrast. The results of this experiment were in agreement with our prediction of attraction towards the high contrast dot. We obtained similar findings when the moving dots were replaced by drifting gratings of unequal contrast. In control experiments, we found that neither attention nor eye movements can account for this illusion. We propose that the visual system uses predictive influences from the motion processing sub-system on the position processing sub-system to overcome the temporal limitations of the position processing system.

Research Doctorate - Doctor of Philosophy (PhD)
The spinal cord dorsal horn (DH) represents an important area in the processing of sensory information. As the first point in the central nervous system (CNS) where peripheral signals input, our understanding of information processing that occurs here is crucial if we are to better manage sensory dysfunction. Chapter 1 details this background along with emphasising the significant heterogeneity that exists in this region, which has made the elucidation of specific DH circuit’s difficult. Fortunately, advances in molecular and genetic techniques have facilitated the targeting of individual neuron populations. Building from this technology, experiments in this thesis examine the role of a specific population of DH neurons that can be identified by expression of the calcium binding protein calretinin (CR). CR has previously been shown to be expressed on a sub population of excitatory interneurons, however little work has been done to identify their role in spinal pain processing. Chapter 2 first examines the electrophysiological and morphological properties of CR+ neurons in the DH. In this analysis I identified two functionally and morphologically distinct populations of CR+ neurons, referred to as Typical and Atypical. Typical CR neurons exhibited features consistent with excitatory interneurons, including high frequency spontaneous excitatory input, delayed action potential (AP) discharge patterns, A-type potassium currents and central, radial or vertical cell morphologies. While, Atypical CR neurons showed inhibitory interneuron characteristics, including low frequency spontaneous excitatory input, tonic AP discharge patterns, Ih currents and islet-like morphology. The spontaneous inhibitory input received by these two populations of CR+ neurons also differed. Typical, excitatory CR neurons receive mixed inhibition from both GABAergic and glycinergic sources, whereas, inhibition of the inhibitory CR+ neurons was glycine dominant (Chapter 3). In order to look at the functional connections of CR+ neurons within the DH I used channel rhodopsin assisted circuit mapping. These experiments identified a high level of connectivity both amongst CR+ neurons and to other, unidentified populations. Importantly, among the identified connections CR+ neurons provided input to identified projection neurons, the functional output cells of the dorsal (sensory) spinal cord. To further resolve the postsynaptic targets of CR+ neurons I next applied spinal optogenetic stimulation in anaesthetised mice, before undertaking c-Fos immunohistochemistry to label activated populations and identify them with neurochemical markers of known DH subpopulations. This showed that, in addition to projection neurons (identified here by NK-1R labelling), CR+ neurons activated a substantial inhibitory population, and selective populations of excitatory interneurons. Finally, I developed a surgical approach to chronically implant a fibre optic probe over the spinal cord. This allowed me to assess the behavioural phenotype associated with spinal CR+ neuron activation. These results showed that in awake and behaving animals CR+ neuron activation generates a strong nocifensive behavioural response that outlasts optogenetic stimulation, shifts over the body surface, potentiates when stimulation is repeated, is blocked by morphine administration, and produces a conditioned place aversion. Overall, my thesis provides a thorough characterisation of CR+ DH neurons at a single cell, circuit and behavioural level. This has greatly contributed to our understanding of sensory processing in the spinal cord, particularly excitatory interneurons, an important population, which has not previously been studied in this level of detail.

Chimpanzee is the closest living species to modern humans. Although the differences in phenotype are striking between these two species, the difference in genomic sequences is surprisingly small. Species specific changes and positive selection have been mostly found in proteins, but ncRNAs are also involved, including the largely uncharacterized class of long ncRNAs (lncRNAs). A notable example is the Human Accelerated Region 1 (HAR1), the region in the human genome with the highest number of human specific substitutions: 18 in 118 nucleotides. HAR1 is located in a pair of overlapping lncRNAs that are expressed in a crucial period for brain development. Importantly, structural rather then sequence constraints lead to evolution of many ncRNAs. Different methods have been developed for detecting negative selection in ncRNA structures, but none thus far for positive selection. This motivated us to develop a novel method: the SSS-test (Selection on the Secondary Structure test). This novel method uses an excess of structure changing changes as a means of identifying positive selection. This is done using reports from RNAsnp, a tool that quantifies the structural effect of SNPs on RNA structures, and by applying multiple correction on the observations to generate selection scores. Insertions and deletions (indels) are dealt with separately using rank statistics and a background model. The scores for SNPs and indels are combined to calculate a final selection score for each of the input sequences, indicating the type of selection. We benchmarked the SSS-test with biological and synthetic datasets, obtaining coherent signals. We then applied it to a lncRNA database and obtained a set of 110 human lncRNAs as candidates for having evolved under adaptive evolution in humans. Although lncRNAs have poor sequence conservation, they have conserved splice sites, which provide ideal guides for orthology annotation. To provide an alternative method for assigning orthology for lncRNAs, we developed the 'buildOrthologs' tool. It uses as input a map of ortholog splice sites created by the SpliceMap tool and applies a greedy algorithm to reconstruct valid ortholog transcripts. We applied this novel approach to create a well-curated catalog of lncRNA orthologs for primate species. Finally, to understand the structural evolution of ncRNAs in full detail, we added a temporal aspect to the analysis. What was the order of mutations of a structure since its origin? This is a combinatorial problem, in which the exact mutations between ancestral and extant sequences must be put in order. For this, we developed the 'mutationOrder' tool using dynamic programming. It calculates every possible order of mutations and assigns probabilities to every path. We applied this novel tool to HAR1 as a case study and saw that the co-optimal paths that are equally likely to have occured share qualitatively comparable features. In general, they lead to stabilization of the human structure since the ancestral. We propose that this stabilization was caused by adaptive evolution. With the new methods we developed and our analysis of primate databases, we gained new knowledge about adaptive evolution of human lncRNAs.

The massive volume of data generated daily by the gathering of medical images with different modalities might be difficult to store in medical facilities and share through communication networks. To alleviate this issue, efficient compression methods must be implemented to reduce the amount of storage and transmission resources required in such applications. However, since the preservation of all image details is highly important in the medical context, the use of lossless image compression algorithms is of utmost importance. This thesis presents the research results on a lossless compression scheme designed to encode both computerized tomography (CT) and positron emission tomography (PET). Different techniques, such as image-to-image translation, intra prediction, and inter prediction are used. Redundancies between both image modalities are also investigated. To perform the image-to-image translation approach, we resort to lossless compression of the original CT data and apply a cross-modality image translation generative adversarial network to obtain an estimation of the corresponding PET. Two approaches were implemented and evaluated to determine a PET residue that will be compressed along with the original CT. In the first method, the residue resulting from the differences between the original PET and its estimation is encoded, whereas in the second method, the residue is obtained using encoders inter-prediction coding tools. Thus, in alternative to compressing two independent picture modalities, i.e., both images of the original PET-CT pair solely the CT is independently encoded alongside with the PET residue, in the proposed method. Along with the proposed pipeline, a post-processing optimization algorithm that modifies the estimated PET image by altering the contrast and rescaling the image is implemented to maximize the compression efficiency. Four different versions (subsets) of a publicly available PET-CT pair dataset were tested. The first proposed subset was used to demonstrate that the concept developed in this work is capable of surpassing the traditional compression schemes. The obtained results showed gains of up to 8.9% using the HEVC. On the other side, JPEG2k proved not to be the most suitable as it failed to obtain good results, having reached only -9.1% compression gain. For the remaining (more challenging) subsets, the results reveal that the proposed refined post-processing scheme attains, when compared to conventional compression methods, up 6.33% compression gain using HEVC, and 7.78% using VVC.

碩士
國立臺灣大學
生化科學研究所
107
Recent studies have emerged that long non-coding RNAs (lncRNAs) play vital role in tumor progression. Here, we identified a novel tumor related lncRNA termed LINAT (Long Intergenic Noncoding RNA Activated by TGF-β). Clinically, high expression of LINAT correlates with poor survival among colorectal, breast and liver cancer patients. Furthermore, LINAT overexpression is associated with lymph node invasion, deteriorated pathology stage as well as vascular invasion in liver and breast cancer patients. However, the expression level of LINAT has no significant difference between normal and tumor tissue. These findings imply that LINAT plays a role in tumor progression, such as invasion/metastasis, but not tumor initiation. To address the role of LINAT in tumor progression, we manipulated LINAT expression in breast and colorectal cancer cell lines by overexpression and knockdown approaches. The data revealed that LINAT induces malignant phenotypes, including epithelial-mesenchymal transition (EMT) phenotype, migration and invasion both in morphological and molecular levels. To uncover how LINAT induces EMT, we conducted RNA-seq to identify LINAT-induced transcriptome and utilized bioinformatics tools, including Ingenuity Pathway Analysis and Gene Set Enrichment Analysis, to characterize its features and compare with the signatures of different signaling pathways. Strikingly, LINAT-induced transcriptome has a significant correlation with the signature of TGF-β signaling. Consistently, both the expression level and promoter activity of TGF-β downstream genes are reduced significantly in LINAT knockdown lines, indicating a promoting role of LINAT in TGF-β signaling. We further found that TGF-β is able to induce LINAT expression in multiple tumor cell lines through a Smad3/4 dependent manner. Our following study shows that LINAT knockdown can decrease the amplitude and duration of TGF-β signaling. Thus, our data indicate that LINAT participates in a feedback control of TGF-β signaling. In conclusion, our results not only identify a novel tumor-promoting lncRNA, LINAT, but also dissect its role in EMT and TGF-β signaling. The LINAT-induced novel positive feedback regulation of TGF-β highlights its role in tumor malignancy and supports our findings from the clinical specimens.