Дисертації з теми "Position coding"
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Adamian, Nika. "Predictive position coding : attentional account of motion-induced position shifts." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB164/document.
Повний текст джерелаLocalizing 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
Ghosna, Fadi Jawdat. "Pulse position modulation coding schemes for optical inter-satellite links in free space." Thesis, University of Huddersfield, 2010. http://eprints.hud.ac.uk/id/eprint/8766/.
Повний текст джерелаGamir, Luis Palafox. "A new method for the determination of the entry position of #gamma#-rays in high purity germanium detectors by current pulse analysis." Thesis, Cranfield University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387640.
Повний текст джерелаBarannik, Vlad, Y. Babenko, S. Shulgin, and M. Parkhomenko. "Video encoding to increase video availability in telecommunication systems." Thesis, Taras Shevchenko National University of Kyiv, 2020. https://openarchive.nure.ua/handle/document/16582.
Повний текст джерелаAliakbari, khoei Mina. "Une approche computationnelle de la dépendance au mouvement du codage de la position dans la système visuel." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4041/document.
Повний текст джерелаCoding 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
Anisimova, Maria. "Detecting positive selection in protein coding genes." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405810.
Повний текст джерелаFujiki, Nobuya. "Influence of speech-coding strategy on cortical activity in cochlear implant users : a positron emission tomographic study." Kyoto University, 1999. http://hdl.handle.net/2433/182287.
Повний текст джерелаBendall, Matthew Lewis. "Evaluating the Performance of Computational Approaches for Identifying Critical Sites in Protein-coding DNA Sequences." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3645.
Повний текст джерелаNovak, Josh. "A Longitudinal Study of Therapist Emotion Focused Therapy Interventions Predicting In-Session Positive Couple Behavior." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/4410.
Повний текст джерелаZhang, Shaoyan. "Overexpression of the Turnip Crinkle Virus Replicase Exerts Opposite Effects on the Synthesis of Viral Genomic RNA and a Novel Viral Long Non-Coding RNA." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595258672390499.
Повний текст джерелаAubry, Fabien. "Development and applications of a new reverse genetics method for the generation of single-stranded positive-sense RNA viruses." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5066.
Повний текст джерелаReverse 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
Diribarne, Gaëlle. "Etude de la régulation du facteur de transcription P-TEFb par la protéine HEXIM1 et l'ARN non codant 7SK." Paris 7, 2010. http://www.theses.fr/2010PA077143.
Повний текст джерелаP-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
Tostivint, Hervé. "Contribution à l'étude de l'évolution des gènes codant la somatostatine chez les vértébrés : mise en évidence chez les amphibiens et les dipneustes d'un nouveau variant de somatostatine muni d'un résidu proline en position deux." Rouen, 2000. http://www.theses.fr/2000ROUES033.
Повний текст джерелаMarguet, Didier. "Analyses structurale et fonctionnelle du gène SRP de Saccharomyces cerevisiae codant pour une protéine riche en résidu sérine : étude de sa régulation transcriptionnelle positive par le glucose." Grenoble 1, 1986. http://www.theses.fr/1986GRE10036.
Повний текст джерелаMarguet, Didier. "Analyses structurale et fonctionnelle du gène SRP de Saccharomyces cerevisiae codant pour une protéine riche en résidu sérine étude de sa régulation transcriptionnelle positive par le glucose." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37599453x.
Повний текст джерелаFlobinus, Alyssa. "Rôle de la protéine p14 du BNYVV et de l'ARN-3 viral dans la suppression de l'interférence par l'ARN et le mouvement à longue distance." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAJ045/document.
Повний текст джерелаThe 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
Azevedo, Fernando Costa de. "O desequilíbrio excessivo da relação jurídica de consumo e sua correção por meio da cláusula geral de proibição de vantagem excessiva no Código de Defesa do Consumidor." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/183751.
Повний текст джерелаA 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.
Jaume, Bennasar Andrés. "Las nuevas tecnologías en la administración de justicia. La validez y eficacia del documento electrónico en sede procesal." Doctoral thesis, Universitat de les Illes Balears, 2009. http://hdl.handle.net/10803/9415.
Повний текст джерелаLa 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.
Yu, Wei-Hsiang, and 游為翔. "Position coding mechansims for binocular disparity revealed by fMRI." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/40370438207364673425.
Повний текст джерела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.
Yang, Yi-Hao, and 楊翼豪. "Application of Full-Digital Coding scheme to Pneumatic Position Control." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/51819845599792190030.
Повний текст джерела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.
Liu, Siyu. "Improved Coding Techniques for MPPM-like Systems." Thesis, 2009. http://hdl.handle.net/1807/18803.
Повний текст джерелаYilmaz, O., Srimant P. Tripathy, S. S. Patel, and Haluk Ogmen. "Attraction of flashes to moving dots." 2007. http://hdl.handle.net/10454/3770.
Повний текст джерелаMotion 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.
Smith, Kelly. "The role of calretinin positive interneurons in spinal sensory coding." Thesis, 2018. http://hdl.handle.net/1959.13/1355332.
Повний текст джерелаThe 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.
Walter, Costa Maria Beatriz. "Adaptive Evolution of Long Non-Coding RNAs." 2018. https://ul.qucosa.de/id/qucosa%3A32389.
Повний текст джерелаParracho, João Oliveira. "JOINT CODING OF MULTIMODAL BIOMEDICAL IMAGES US ING CONVOLUTIONAL NEURAL NETWORKS." Master's thesis, 2020. http://hdl.handle.net/10400.8/6682.
Повний текст джерелаLIU, XINXIN, та 劉欣欣. "Long non-coding RNA LINAT controls a positive feedback regulation of TGF-β signaling to promote tumor progression". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/vn85r3.
Повний текст джерела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.
Kang, Jee Eun. "Novel bioinformatics programs for taxonomical classification and functional analysis of the whole genome sequencing data of arbuscular mycorrhizal fungi." Thèse, 2018. http://hdl.handle.net/1866/21799.
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