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Kisel, Andrej. "Person Identification by Fingerprints and Voice". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101230_093643-05320.
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This dissertation focuses on person identification problems and proposes solutions to overcome those problems. First part is about fingerprint features extraction algorithm performance evaluation. Modifications to a known synthesis algorithm are proposed to make it fast and suitable for performance evaluation. Matching of deformed fingerprints is discussed in the second part of the work. New fingerprint matching algorithm that uses local structures and does not perform fingerprint alignment is proposed to match deformed fingerprints. The use of group delay features of linear prediction model for speaker recognition is proposed in the third part of the work. New similarity metric that uses group delay features is described. It is demonstrated that automatic speaker recognition system with proposed features and similarity metric outperforms traditional speaker identification systems . Multibiometrics using fingerprints and voice is addressed in the last part of the dissertation.Penkiose disertacijos darbo dalyse nagrinėjamos žmogaus identifikavimo pagal pirštų atspaudus ir balsą problemos ir siūlomi jų sprendimai. Pirštų atspaudų požymių išskyrimo algoritmų kokybės įvertinimo problemą siūloma spręsti panaudojant sintezuotus pirštų atspaudus. Darbe siūlomos žinomo pirštų atpaudų sintezės algoritmo modifikacijos, kurios leidžia sukurti piršto atspaudo vaizdą su iš anksto nustatytomis charakteristikomis ir požymiais bei pagreitina sintezės procesą. Pirštų atspaudų požymių palyginimo problemos yra aptartos ir naujas palyginimo algoritmas yra siūlomas deformuotų pirštų palyginimui. Algoritmo kokybė yra įvertinta ant viešai prieinamų ir vidinių duomenų bazių. Naujas asmens identifikavimo pagal balsą metodas remiantis tiesinės prognozės modelio grupinės delsos požymiais ir tų požymių palyginimo metrika kokybės prasme lenkia tradicinius asmens identifikavimo pagal balsą metodus. Pirštų ir balso įrašų nepriklausomumas yra irodytas ir asmens atpažinimas pagal balsą ir pirštų atspaudus kartu yra pasiūlytas siekiant išspręsti bendras biometrinių sistemų problemas.
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Gudnason, Jon. "Voice source cepstrum processing for speaker identification". Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439448.
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Iliadi, Konstantina. "Bio-inspired voice recognition for speaker identification". Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/413949/.
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Speaker identification (SID) aims to identify the underlying speaker(s) given a speech utterance. In a speaker identification system, the first component is the front-end or feature extractor. Feature extraction transforms the raw speech signal into a compact but effective representation that is more stable and discriminative than the original signal. Since the front-end is the first component in the chain, the quality of the later components is strongly determined by its quality. Existing approaches have used several feature extraction methods that have been adopted directly from the speech recognition task. However, the nature of these two tasks is contradictory given that speaker variability is one of the major error sources in speech recognition whereas in speaker recognition, it is the information that we wish to extract. In this thesis, the possible benefits of adapting a biologically-inspired model of human auditory processing as part of the front-end of a SID system are examined. This auditory model named Auditory Image Model (AIM) generates the stabilized auditory image (SAI). Features are extracted by the SAI through breaking it into boxes of different scales. Vector quantization (VQ) is used to create the speaker database with the speakers’ reference templates that will be used for pattern matching with the features of the target speakers that need to be identified. Also, these features are compared to the Mel-frequency cepstral coefficients (MFCCs), which is the most evident example of a feature set that is extensively used in speaker recognition but originally developed for speech recognition purposes. Additionally, another important parameter in SID systems is the dimensionality of the features. This study addresses this issue by specifying the most speaker-specific features and trying to further improve the system configuration for obtaining a representation of the auditory features with lower dimensionality. Furthermore, after evaluating the system performance in quiet conditions, another primary topic of speaker recognition is investigated. SID systems can perform well under matched training and test conditions but their performance degrades significantly because of the mismatch caused by background noise in real-world environments. Achieving robustness to SID systems becomes an important research problem. In the second experimental part of this thesis, the developed version of the system is assessed for speaker data sets of different size. Clean speech is used for the training phase while speech in the presence of babble noise is used for speaker testing. The results suggest that the extracted auditory feature vectors lead to much better performance, i.e. higher SID accuracy, compared to the MFCC-based recognition system especially for low SNRs. Lastly, the system performance is inspected with regard to parameters related to the training and test speech data such as the duration of the spoken material. From these experiments, the system is found to produce satisfying identification scores for relatively short training and test speech segments.
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Haider, Zargham. "Robust speaker identification against computer aided voice impersonation". Thesis, University of Surrey, 2011. http://epubs.surrey.ac.uk/770387/.
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Speaker Identification (SID) systems offer good performance in the case of noise free speech and most of the on-going research aims at improving their reliability in noisy environments. In ideal operating conditions very low identification error rates can be achieved. The low error rates suggest that SID systems can be used in real-life applications as an extra layer of security along with existing secure layers. They can, for instance, be used alongside a Personal Identification Number (PIN) or passwords. SID systems can also be used by law enforcements agencies as a detection system to track wanted people over voice communications networks. In this thesis, the performance of 'the existing SID systems against impersonation attacks is analysed and strategies to counteract them are discussed. A voice impersonation system is developed using Gaussian Mixture Modelling (GMM) utilizing Line Spectral Frequencies (LSF) as the features representing the spectral parameters of the source-target pair. Voice conversion systems based on probabilistic approaches suffer from the problem of over smoothing of the converted spectrum. A hybrid scheme using Linear Multivariate Regression and GMM, together with posterior probability smoothing is proposed to reduce over smoothing and alleviate the discontinuities in the converted speech. The converted voices are used to intrude a closed-set SID system in the scenarios of identity disguise and targeted speaker impersonation. The results of the intrusion suggest that in their present form the SID systems are vulnerable to deliberate voice conversion attacks. For impostors to transform their voices, a large volume of speech data is required, which may not be easily accessible. In the context of improving the performance of SID against deliberate impersonation attacks, the use of multiple classifiers is explored. Linear Prediction (LP) residual of the speech signal is also analysed for speaker-specific excitation information. A speaker identification system based on multiple classifier system, using features to describe the vocal tract and the LP residual is targeted by the impersonation system. The identification results provide an improvement in rejecting impostor claims when presented with converted voices. It is hoped that the findings in this thesis, can lead to the development of speaker identification systems which are better equipped to deal with the problem with deliberate voice impersonation.
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Atkinson, Nathan. "Variable factors affecting voice identification in forensic contexts". Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/13013/.
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Fredrickson, Steven Eric. "Neural networks for speaker identification". Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294364.
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Gillivan-Murphy, Patricia. "Voice tremor in Parkinson's disease (PD) : identification, characterisation and relationship with speech, voice and disease variables". Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2170.
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Voice tremor is associated with Parkinson’s disease (PD), however little is known about the precise characteristics of PD voice tremor, optimum methods of evaluation or possible relationships with other speech, voice, and disease variables. The question of possible differences between voice tremor in people with PD (pwPD) and neurologically healthy ageing people has not been addressed. Thirty pwPD ‘off-medication’ and twenty eight age-sex matched neurologically healthy controls were evaluated for voice tremor features using acoustic measurement, auditory perceptual voice rating, and nasendoscopic vocal tract examination. Speech intelligibility, severity of voice impairment, voice disability and disease variables (duration, disability, motor symptom severity, phenotype) were measured and examined for relationship with acoustic voice tremor measures. Results showed that pwPD were more likely to show greater auditory perceived voice instability and a greater magnitude of frequency and amplitude tremor in comparison to controls, however without statistical significance. PwPD had a higher rate of amplitude tremor than controls (p<0.05). Judged from ‘silent’ video recordings of nasendoscopic examination, pwPD had a greater amount of tremor in the palate, tongue, and global larynx (vertical dimension) than controls during rest breathing, sustained /s/, /a/ and /i/ (p<0.05). Acoustic voice tremor did not relate significantly to other speech and voice variables. PwPD had a significantly higher voice disability than controls (p<0.05), though this was independent of voice tremor. The magnitude of frequency tremor was positively associated with disease duration (p<0.05). A lower rate of amplitude tremor was associated with an increase in motor symptoms severity (p<0.05). Acoustic voice tremor did not relate in any significant way to PD disability or phenotype. ii PD voice tremor is characterised by auditory perceived instability and tremor, a mean amplitude tremor of 4.94 Hz, and tremor in vocal tract structures. Acoustic analysis and nasendoscopy proved valuable adjunctive tools for characterising voice tremor. Voice tremor is not present in all people with PD, but does appear to increase with disease duration. However pwPD examined here represent a relatively mild group with relatively short disease duration. Further work will look at people with more severe disease symptomatology and longer duration.
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Wildermoth, Brett Richard, i n/a. "Text-Independent Speaker Recognition Using Source Based Features". Griffith University. School of Microelectronic Engineering, 2001. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040831.115646.
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Speech signal is basically meant to carry the information about the linguistic message. But, it also contains the speaker-specific information. It is generated by acoustically exciting the cavities of the mouth and nose, and can be used to recognize (identify/verify) a person. This thesis deals with the speaker identification task; i.e., to find the identity of a person using his/her speech from a group of persons already enrolled during the training phase. Listeners use many audible cues in identifying speakers. These cues range from high level cues such as semantics and linguistics of the speech, to low level cues relating to the speaker's vocal tract and voice source characteristics. Generally, the vocal tract characteristics are modeled in modern day speaker identification systems by cepstral coefficients. Although, these coeficients are good at representing vocal tract information, they can be supplemented by using both pitch and voicing information. Pitch provides very important and useful information for identifying speakers. In the current speaker recognition systems, it is very rarely used as it cannot be reliably extracted, and is not always present in the speech signal. In this thesis, an attempt is made to utilize this pitch and voicing information for speaker identification. This thesis illustrates, through the use of a text-independent speaker identification system, the reasonable performance of the cepstral coefficients, achieving an identification error of 6%. Using pitch as a feature in a straight forward manner results in identification errors in the range of 86% to 94%, and this is not very helpful. The two main reasons why the direct use of pitch as a feature does not work for speaker recognition are listed below. First, the speech is not always periodic; only about half of the frames are voiced. Thus, pitch can not be estimated for half of the frames (i.e. for unvoiced frames). The problem is how to account for pitch information for the unvoiced frames during recognition phase. Second, the pitch estimation methods are not very reliable. They classify some of the frames unvoiced when they are really voiced. Also, they make pitch estimation errors (such as doubling or halving of pitch value depending on the method). In order to use pitch information for speaker recognition, we have to overcome these problems. We need a method which does not use the pitch value directly as feature and which should work for voiced as well as unvoiced frames in a reliable manner. We propose here a method which uses the autocorrelation function of the given frame to derive pitch-related features. We call these features the maximum autocorrelation value (MACV) features. These features can be extracted for voiced as well as unvoiced frames and do not suffer from the pitch doubling or halving type of pitch estimation errors. Using these MACV features along with the cepstral features, the speaker identification performance is improved by 45%.
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Wildermoth, Brett Richard. "Text-Independent Speaker Recognition Using Source Based Features". Thesis, Griffith University, 2001. http://hdl.handle.net/10072/366289.
Pełny tekst źródłaStreszczenie:
Speech signal is basically meant to carry the information about the linguistic message. But, it also contains the speaker-specific information. It is generated by acoustically exciting the cavities of the mouth and nose, and can be used to recognize (identify/verify) a person. This thesis deals with the speaker identification task; i.e., to find the identity of a person using his/her speech from a group of persons already enrolled during the training phase. Listeners use many audible cues in identifying speakers. These cues range from high level cues such as semantics and linguistics of the speech, to low level cues relating to the speaker's vocal tract and voice source characteristics.
Generally, the vocal tract characteristics are modeled in modern day speaker identification systems by cepstral coefficients. Although, these coeficients are good at representing vocal tract information, they can be supplemented by using both pitch and voicing information. Pitch provides very important and useful information for identifying speakers. In the current speaker recognition systems, it is very rarely used as it cannot be reliably extracted, and is not always present in the speech signal. In this thesis, an attempt is made to utilize this pitch and voicing information for speaker identification.
This thesis illustrates, through the use of a text-independent speaker identification system, the reasonable performance of the cepstral coefficients, achieving an identification error of 6%. Using pitch as a feature in a straight forward manner results in identification errors in the range of 86% to 94%, and this is not very helpful. The two main reasons why the direct use of pitch as a feature does not work for speaker recognition are listed below. First, the speech is not always periodic; only about half of the frames are voiced. Thus, pitch can not be estimated for half of the frames (i.e. for unvoiced frames). The problem is how to account for pitch information for the unvoiced frames during recognition phase. Second, the pitch estimation methods are not very reliable.
They classify some of the frames unvoiced when they are really voiced. Also, they make pitch estimation errors (such as doubling or halving of pitch value depending on the method). In order to use pitch information for speaker recognition, we have to overcome these problems. We need a method which does not use the pitch value directly as feature and which should work for voiced as well as unvoiced frames in a reliable manner. We propose here a method which uses the autocorrelation function of the given frame to derive pitch-related features. We call these features the maximum autocorrelation value (MACV) features. These features can be extracted for voiced as well as unvoiced frames and do not suffer from the pitch doubling or halving type of pitch estimation errors. Using these MACV features along with the cepstral features, the speaker identification performance is improved by 45%.Thesis (Masters)
Master of Philosophy (MPhil)
School of Microelectronic Engineering
Faculty of Engineering and Information Technology
Full Text
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Rouse, Kenneth Arthur Gilbert Juan E. "Classifying speakers using voice biometrics In a multimodal world". Auburn, Ala, 2009. http://hdl.handle.net/10415/1824.
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Austin, Catherine. "The identification of psychological and social processes involved in Psychogenic Voice Disorder". Thesis, University of East London, 1997. http://roar.uel.ac.uk/3647/.
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The research aimed to identify the psychological and social processes involved in Psychogenic Voice Disorder (PVD). Both quantitative and qualitative methodologies were utilised in this study. The quantitative part of the study consisted of a questionnaire which sought to assess biographical details of this population and establish the patient's perception of their voice problem. The qualitative part of the study consisted of in-depth interviewing based on the principles of grounded theory and aimed to identify the processes involved in PVD. The patients who took part were from a Voice Clinic at a London teaching hospital. The results support previous research which concluded that PVD is a predominantly female disorder. The results indicate that PVD is caused and maintained by a complex interaction of psychological and social processes. The main processes in this interaction were found to be, Conflict over Speaking Out (CSO), background influences, powerlessness, fear of consequences, musculoskeletal tension, burden of responsibility and avoidance. In the discussion it is suggested that from the results and in the consideration of the history of PVD, the patient's perceived social position in society may be the concept that links the identified processes involved in the causation and maintenance of PVD. The thesis concludes by briefly considering some areas of future research.
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Armstrong, Paul-Alan. "Songs of praxis : reflexive space for authentic teacher voice identification, development and transformation". Thesis, University of Sunderland, 2015. http://sure.sunderland.ac.uk/7336/.
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This study was conceptualised within the Aristotelian tradition of phronesis and dialectics (Eikeland, 2006; 2012) where the focus of the study was the identification of teacher's voice (Sutherland et al., 2010) using Songs of Praxis, an art-based reflexive account within a reflexivity paradigm of uncovering biographical perspective of identity (Alheit, 1992; 2009). This had two reflexivity contexts; within research (e.g. Rolfe, 2011a; 2011b; Rolfe, Jasper and Freshwater, 2011; Etherington, 2007; Simon, 2013; Ellis, 2004; 2007; 2011) and within critical reflective practice (e.g. Gardner, 2009; Gardner, 2014; Rolfe, Jasper and Freshwater, 2011). This reflexive process led to teacher voice development and transformation through a hybridity of creative pedagogy, teaching for creativity and creative learning (Lin, 2011; 2014; Sawyer 2004; 2011). This visualization was completed using reflexive accounts (referred to as Songs of Praxis) which created space for a reflexive relationship (Etherington, 2007; Ellis, 2004) allowing for emotional recall (understanding biographical identity) through to therapeutic inquiry by dealing with my Mask of Self-Hate (the name I use to describe my bipolarity). This facilitated my authentication and transformation as a scholar of learning and teaching. This study was conducted within an auto ethnographic action research and reflexive accounts methodology using cycles of critical reflection. The cycles of critical reflection are; teacher voice identification stage 1, the reimagination of professional voice framework leading to teacher voice identification stage 2, the multiplicity of voice prism. This led to teacher voice development stage1, the reflexive provocateur toolkit which developed into the Reflexive Classroom, teacher voice development stage 2. This led to the teacher voice transformation through the creation of reflexive spaces of creative pedagogic practices; digital reflexivity; and employability practices. This allowed for teacher voice identification, development and transformation which I illustrate within the 'portfolio' which I conceptualised around an 'Album', Songs of Praxis: Teacher Voice Identification, development and transformation'. This corroboration of the data (experience) has led to the contribution of this study to creative teaching practices, digital reflexivity and employability practices. I propose Songs of Praxis create reflexive space for the identification, development and transformation of teacher's voice.
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Raghunathan, Anusha. "EVALUATION OF INTELLIGIBILITY AND SPEAKER SIMILARITY OF VOICE TRANSFORMATION". UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/101.
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Voice transformation refers to a class of techniques that modify the voice characteristics either to conceal the identity or to mimic the voice characteristics of another speaker. Its applications include automatic dialogue replacement and voice generation for people with voice disorders. The diversity in applications makes evaluation of voice transformation a challenging task. The objective of this research is to propose a framework to evaluate intentional voice transformation techniques. Our proposed framework is based on two fundamental qualities: intelligibility and speaker similarity. Intelligibility refers to the clarity of the speech content after voice transformation and speaker similarity measures how well the modified output disguises the source speaker. We measure intelligibility with word error rates and speaker similarity with likelihood of identifying the correct speaker. The novelty of our approach is, we consider whether similarly transformed training data are available to the recognizer. We have demonstrated that this factor plays a significant role in intelligibility and speaker similarity for both human testers and automated recognizers. We thoroughly test two classes of voice transformation techniques: pitch distortion and voice conversion, using our proposed framework. We apply our results for patients with voice hypertension using video self-modeling and preliminary results are presented.
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Akarapu, Deepika. "Object Identification Using Mobile Device for Visually Impaired Person". University of Dayton / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1628092619349812.
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Sepielak, Katarzyna. "Voice-over in multilingual fiction movies in Poland. Translation and synchronization techniques, content comprehension and language identification". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/392684.
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Esta tesis doctoral analiza las voces superpuestas de películas multilingües en Polonia. Primero se centra en diferentes técnicas de traducción y sincronización aplicadas en las voces superpuestas en películas multilingües y luego analiza el procesamiento de la información, la comprensión y la identificación de los distintos idiomas en las películas con voces superpuestas. Se han formulados tres objetivos: 1) Establecer cómo los elementos multilingües se traducen en las películas con voces superpuestas en polaco; 2) Establecer la relación entre las técnicas de sincronización y traducción de las películas multilingües con voces superpuestas y analizar qué combinaciones de técnicas de sincronización y de traducción son más eficientes en la expresión de contexto multilingüe; 3) Analizar cómo los elementos multilingües son procesados, tanto en películas multilingües con voces superpuestas como con subtítulos. Con estos objetivos en mente, se han llevado a cabo dos estudios descriptivos y uno experimental.
El primer estudio muestra que la introducción de elementos multilingües en los textos de origen es un procedimiento deliberado, que a menudo desaparece en los textos de llegada. El análisis del corpus muestra que los elementos multilingües se reducen significativamente en las versiones polacas. El análisis revela que sólo dos técnicas, de imitación y de exposición, refuerzan el contexto multilingüe en las versiones traducidas. Otras técnicas más frecuentes borran la diversidad lingüística presente en las versiones originales. Sin embargo, como la banda sonora original en las películas con voces superpuestas es audible hasta cierto punto, la sincronización hábil de las dos bandas sonoras ayuda a marcar contexto multilingüe en las películas.
El segundo estudio indica que existe cierta relación entre los diferentes tipos de sincronía y algunas técnicas de traducción, sobre todo, la condensación, la transferencia, la paráfrasis y decimación. Sin embargo cada sincronía muestra diferentes patrones en cuanto a la naturaleza de esta relación. En el caso de isocronía, la relación es definitivamente no causal. La práctica habitual consiste en el hecho de que el lector lea la traducción después de escuchar el original, sin pautas en cuanto al número exacto de segundos que deben pasar antes de comenzar la lectura de la traducción. La sincronía literal aparece en muy pocos casos. La relación de este tipo de sincronía con las técnicas de traducción también es casual. La sincronía quinésica se mantiene en la mayoría de los casos gracias a las técnicas de transferencia y condensación. El análisis también revela que de los cuatro tipos de sincronías, la isocronía es la única que ayuda a exponer contexto multilingüe en las películas. Dada su naturaleza, ya que expone la banda sonora original aunque por un corto período de tiempo, esta sincronía podría aumentar la diversidad lingüística en la película. Estos resultados llevan a la pregunta si esta diversidad es procesada por los espectadores. Esta cuestión se trata empíricamente en el tercer estudio. Por razones comparativas y de control, el tercer estudio añade el subtitulado para el análisis.
Los resultados del experimento muestran que la comprensión del contenido depende de la modalidad de traducción audiovisual, con mejores resultados en la condición de subtitulado que de las voces superpuestas. Los resultados sugieren que el procesamiento de información en los programas con voces superpuestas no es tan eficiente como en la versión subtitulada. Los resultados indican que el modo de traducción audiovisual no predice el rendimiento en la detección del número de idiomas hablados por los personajes en producciones multilingües. Por último, se concluye que ni la modalidad de traducción audiovisual ni los personajes multilingües y monolingües son predictores significativos de la identificación de idiomas hablados por personajes en una película multilingüe.This dissertation analyzed voiced-over multilingual movies in Poland. In particular, it focused on different translation and synchronization techniques applied in voiced-over multilingual movies and then shifted its focus to information processing, comprehension and identification of various languages in voiced-over movies. Three main objectives were formulated in this research: 1) To establish how multilingual elements are translated in voiced-over movies into Polish; 2) To establish the relationship between synchronization and translation techniques in multilingual movies voiced-over into Polish and to analyze which combinations of synchronization and translation techniques are most efficient in rendering multilingual context; and 3) To test how multilingual elements are processed by Polish viewers in both voiced-over and subtitled multilingual movies. With those objectives in mind, two descriptive and one experimental studies were carried out. The first study showed that introducing multilingual elements in source texts was a deliberate procedure, which often disappeared in the target text. The analysis of the corpus showed that multilingual elements were significantly reduced in the Polish versions. The analysis revealed that although many translation techniques were detected in utterances with L3 elements, only two techniques—imitation and exhibition—reinforced multilingual content in the translated version. Other techniques, most frequently encountered, just erased linguistic diversity present in the original versions. However, as the original soundtrack in voiced-over movies is still audible to some point, skillful synchronization of the two soundtracks helped in marking multilingual context in the movie. The second study indicated that the relationship between different synchrony types and some translation techniques, mainly condensation, transfer, paraphrase and decimation did exist but each synchrony showed different patterns as to the nature of this relationship. In the case of voice-over isochrony, the relationship was definitely not causal. The standard practice consisted of the voice artists reading the translation after hearing the original utterance with no guidelines specifying the exact number of seconds they should leave before starting reading the translation. Literal synchrony appeared in very few cases. The relationship of this type of synchrony with translation techniques could also be qualified as random Action and kinetic synchronies, on the other hand, were kept in most of the cases and transfer and condensation were the most common techniques that could be related to them. The analysis also revealed that out of four types of synchronies, voice-over isochrony is the only one which actually helped expose multilingual context in the movie. Given its nature, as it exposed the original soundtrack even if for a short amount of time, this synchrony might enhance the linguistic diversity in the movie. This led to the question whether this diversity was in fact processed by viewers, an inquiry that was empirically addressed in the third study. For comparative and controlling reasons, the third study introduced subtitling to the analysis. The results of the experiment showed that content comprehension depended on the audiovisual translation mode, yielding higher levels of performance in the subtitled condition than in the voice-over one. At the same time, the findings suggested that information processing in voiced-over programs was not as efficient as in the subtitled version. Second, the results indicated that the audiovisual translation mode did not predict the performance on detection of the number of languages spoken by character in multilingual productions. Finally, it was concluded that neither the AVT mode nor the multilingual and monolingual characters were significant predictors of character– language pair identification in a multilingual movie.
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Dhakal, Parashar. "Novel Architectures for Human Voice and Environmental Sound Recognitionusing Machine Learning Algorithms". University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1531349806743278.
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Shalita, Martin P. "The Operas of Ralph Vaughan Williams: An Identification and Performance Analysis of the Arias and Duet Scenes for Male Voice". Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/553.
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Ralph Vaughan Williams (1872-1958) was one of the most prolific British composers of the twentieth century, yet his operas are virtually unknown in the standard operatic repertoire. Singers and teachers of singing are often challenged in finding operatic arias composed in the English language, because the standard operatic repertoire simply does not have as many works originally written in English as are found in Italian, German, or French. If there are arias from Vaughan Williams’ operas that are accessible to the young singing voice, they should not remain unknown. This study was executed in hopes of identifying for singers and teachers of singing, the arias, duets and scenes for male voice that can stand alone outside performances of the operas. The implications of this research project are that singers and teachers of singing have a newly found wealth of repertoire to utilize in performance as well as in the learning environment. Not only are these findings beautiful music from one of the twentieth century’s most prominent composers, but they are perhaps more importantly, accessible to the young and developing singer.
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Bich, Serhiy [Verfasser], i Detmar [Akademischer Betreuer] Meurers. ""Is There Choice in Non-Native Voice?" Linguistic Feature Engineering and a Variationist Perspective in Automatic Native Language Identification / Serhiy Bich ; Betreuer: Detmar Meurers". Tübingen : Universitätsbibliothek Tübingen, 2017. http://d-nb.info/1167243757/34.
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Tahon, Marie. "Analyse acoustique de la voix émotionnelle de locuteurs lors d’une interaction humain-robot". Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112275/document.
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Mes travaux de thèse s'intéressent à la voix émotionnelle dans un contexte d'interaction humain-robot. Dans une interaction réaliste, nous définissons au moins quatre grands types de variabilités : l'environnement (salle, microphone); le locuteur, ses caractéristiques physiques (genre, âge, type de voix) et sa personnalité; ses états émotionnels; et enfin le type d'interaction (jeu, situation d'urgence ou de vie quotidienne). A partir de signaux audio collectés dans différentes conditions, nous avons cherché, grâce à des descripteurs acoustiques, à imbriquer la caractérisation d'un locuteur et de son état émotionnel en prenant en compte ces variabilités.Déterminer quels descripteurs sont essentiels et quels sont ceux à éviter est un défi complexe puisqu'il nécessite de travailler sur un grand nombre de variabilités et donc d'avoir à sa disposition des corpus riches et variés. Les principaux résultats portent à la fois sur la collecte et l'annotation de corpus émotionnels réalistes avec des locuteurs variés (enfants, adultes, personnes âgées), dans plusieurs environnements, et sur la robustesse de descripteurs acoustiques suivant ces quatre variabilités. Deux résultats intéressants découlent de cette analyse acoustique: la caractérisation sonore d'un corpus et l'établissement d'une liste "noire" de descripteurs très variables. Les émotions ne sont qu'une partie des indices paralinguistiques supportés par le signal audio, la personnalité et le stress dans la voix ont également été étudiés. Nous avons également mis en oeuvre un module de reconnaissance automatique des émotions et de caractérisation du locuteur qui a été testé au cours d'interactions humain-robot réalistes. Une réflexion éthique a été menée sur ces travauxThis thesis deals with emotional voices during a human-robot interaction. In a natural interaction, we define at least, four kinds of variabilities: environment (room, microphone); speaker, its physic characteristics (gender, age, voice type) and personality; emotional states; and finally the kind of interaction (game scenario, emergency, everyday life). From audio signals collected in different conditions, we tried to find out, with acoustic features, to overlap speaker and his emotional state characterisation taking into account these variabilities.To find which features are essential and which are to avoid is hard challenge because it needs to work with a high number of variabilities and then to have riche and diverse data to our disposal. The main results are about the collection and the annotation of natural emotional corpora that have been recorded with different kinds of speakers (children, adults, elderly people) in various environments, and about how reliable are acoustic features across the four variabilities. This analysis led to two interesting aspects: the audio characterisation of a corpus and the drawing of a black list of features which vary a lot. Emotions are ust a part of paralinguistic features that are supported by the audio channel, other paralinguistic features have been studied such as personality and stress in the voice. We have also built automatic emotion recognition and speaker characterisation module that we have tested during realistic interactions. An ethic discussion have been driven on our work
20
GROVES, WRIGHT KATHY J. "ACOUSTICS AND PERCEPTION OF WET VOCAL QUALITY IN IDENTIFYING PENETRATION/ASPIRATION DURING SWALLOWING". University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1176987749.
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21
Viamontes, Quintero Jesika. "A Mixed Method Inquiry into Student Academic Optimism: Validation of the Construct and Its Use to Give Voice to Latinx Student Experiences". Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703281/.
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This study examined student academic optimism in four diverse North Texas school districts. This study used a convergent parallel mixed methods design to analyze results of an online administration of the survey, and Latinx student responses to a focus group protocol derived from the survey. Quantitative results indicate the individual scales making up the construct align with previous research results. The three scales were found to be strongly and significantly correlated, indicating the potential for validation. Qualitative results indicate Latinx students' perceptions of their academic careers align with four themes. Latinx students are keenly aware of their teachers as a person, their school as a community, the intrusion of the outside world, and students as agents. Qualitative results support the importance of the three components of the construct, student trust in teachers, student academic press, and student identification with school. As a new source of data, combined with existing metrics of instructional effectiveness, student academic optimism could increase the ability of decision makers to improve the overall efficacy of school systems especially when addressing the persistent opportunity gaps for Latinx and other students of color.
22
Sanderson, Conrad, i conradsand@ieee org. "Automatic Person Verification Using Speech and Face Information". Griffith University. School of Microelectronic Engineering, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030422.105519.
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Identity verification systems are an important part of our every day life. A typical example is the Automatic Teller Machine (ATM) which employs a simple identity verification scheme: the user is asked to enter their secret password after inserting their ATM card; if the password matches the one prescribed to the card, the user is allowed access to their bank account. This scheme suffers from a major drawback: only the validity of the combination of a certain possession (the ATM card) and certain knowledge (the password) is verified. The ATM card can be lost or stolen, and the password can be compromised. Thus new verification methods have emerged, where the password has either been replaced by, or used in addition to, biometrics such as the persons speech, face image or fingerprints. Apart from the ATM example described above, biometrics can be applied to other areas, such as telephone & internet based banking, airline reservations & check-in, as well as forensic work and law enforcement applications. Biometric systems based on face images and/or speech signals have been shown to be quite effective. However, their performance easily degrades in the presence of a mismatch between training and testing conditions. For speech based systems this is usually in the form of channel distortion and/or ambient noise; for face based systems it can be in the form of a change in the illumination direction. A system which uses more than one biometric at the same time is known as a multi-modal verification system; it is often comprised of several modality experts and a decision stage. Since a multi-modal system uses complimentary discriminative information, lower error rates can be achieved; moreover, such a system can also be more robust, since the contribution of the modality affected by environmental conditions can be decreased. This thesis makes several contributions aimed at increasing the robustness of single- and multi-modal verification systems. Some of the major contributions are listed below. The robustness of a speech based system to ambient noise is increased by using Maximum Auto-Correlation Value (MACV) features, which utilize information from the source part of the speech signal. A new facial feature extraction technique is proposed (termed DCT-mod2), which utilizes polynomial coefficients derived from 2D Discrete Cosine Transform (DCT) coefficients of spatially neighbouring blocks. The DCT-mod2 features are shown to be robust to an illumination direction change as well as being over 80 times quicker to compute than 2D Gabor wavelet derived features. The fragility of Principal Component Analysis (PCA) derived features to an illumination direction change is solved by introducing a pre-processing step utilizing the DCT-mod2 feature extraction. We show that the enhanced PCA technique retains all the positive aspects of traditional PCA (that is, robustness to compression artefacts and white Gaussian noise) while also being robust to the illumination direction change. Several new methods, for use in fusion of speech and face information under noisy conditions, are proposed; these include a weight adjustment procedure, which explicitly measures the quality of the speech signal, and a decision stage comprised of a structurally noise resistant piece-wise linear classifier, which attempts to minimize the effects of noisy conditions via structural constraints on the decision boundary.
23
Večeřa, Stanislav. "Návrh řešení automatické identifikace v logistickém centru". Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2010. http://www.nusl.cz/ntk/nusl-222560.
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The master's thesis describes working procedures of the pharmaceutical warehousing and distribution, analyses actual methods of communication and identification and shows the weaknesses of this system. The work offers possible innovations, actual trends in the field of the automatic identification, warehouse management and proposes taking advantage of combination of voice recognition and bar-codes system. The thesis describes the new technology implementation, continuing the current practice and update of standard operating procedures.
24
Тодорів, Андрій Дмитрович. "Система багатофакторної аутентифікації користувачів комп’ютерних систем". Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/38366.
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Вирішення проблеми захисту корпоративних даних в ХХІ столітті вийшло за рамки фізичної взаємодії з працівниками, у зв’язку з переходом шуканої інформації в комп’ютерний формат. Дана особливість сформувала потребу у розробці та імплементації нових механізмів захисту корпоративних даних.
Запропонована система аутентифікації користувачів комп’ютерних систем, розроблена на основі технологій нейронних мереж, надає можливість ідентифікації користувачів на основі індивідуальних антропометричних візуальних та голосових показників суб’єкта, з метою запобігання викраденню корпоративних даних, та ідентифікації злочинних суб’єктів.
Об’єктом дослідження є трансформація антропометричних показників в комп’ютерну форму.
Предметом дослідження є механізми розпізнавання образів.
Метою роботи є покращення можливостей методів біометричної ідентифікації суб’єктів шляхом розробки нової архітектури на базі нейронних мереж.
Методи дослідження. Порівняння існуючих алгоритмів за критеріями точності, швидкодії, ресурсних затрат, надійності, з метою імплементації та подальшої модифікації в системі корпоративного контролю.
Наукова новизна полягає у розробці нового механізму ідентифікації суб’єктів що поєднує у собі алгоритми голосової та візуальної ідентифікації суб’єктів.
Практична цінність полягає у можливості застосування даної системи в корпоративних умовах з метою запобігання витоку даних та ідентифікації злочинних суб’єктів. Низька ресурсозатратність сприяє застосуванню розробленого алгоритму в високонавантажених системах.
Структура та обсяг роботи. Магістерська дисертація складається з вступу, чотирьох розділів, висновків та додатків.
У вступі аналізується проблема захисту корпоративних даних. Обгрунтовується перспективність застосування механізмів біометричної голосової та візуальної ідентифікації суб’єктів для її вирішення. Досліджуються алгоритми біометричної ідентифікації.
У першому розділі описуються існуючі алгоритми розпізнавання візуальних та голосових образів.
У другому розділі досліджується доцільність застосування існуючих алгоритмів голосової та візуальної біометричної ідентифікації, аналізуються та порівнюються існуючі архітектури розпізнавання образів.
У третьому розділі наводиться процес розробки алгоритмів візуальної та голосової біометричної ідентифікації користувачів
У четвертому розділі наводяться характеристики розробленої КС, результати тестування, відбувається дослідження системи на різних наборах даних, та її модифікація з метою досягнення поставленої точності.
У висновках стисло наводяться результати досліджень та розробки.Topic relevance The solution to the problem of corporate data protection in the XXI century has gone beyond the physical interaction with employees, due to the transition of the required information into a computer format. This feature has formed the need to develop and implement new mechanisms for corporate data protection. The proposed system of authentication of computer system users, developed on the basis of neural network technologies, provides the possibility of user identification on the basis of individual anthropometric visual and voice indicators of the subject, in order to prevent theft of corporate data and identification of criminal entities. The object of study is the transformation of anthropometric indicators into a computer form. The subject of study is the mechanisms of pattern recognition. The goal of this work is to improve the capabilities of biometric identification methods of subjects by developing a new architecture based on neural networks. Study methods. Comparison of existing algorithms on the criteria of accuracy, speed, resource costs, reliability, in order to implement and further modify the corporate control system. The scientific novelty is the development of a new mechanism for identifying subjects that combines algorithms for voice and visual identification of subjects. The practical value lies in the possibility of using this system in a corporate environment in order to prevent data leakage and identification of criminal entities. Low resource consumption contributes to the application of the developed algorithm in highly loaded systems. Structure and scope of work. The master's dissertation consists of an introduction, four chapters, conclusions and appendices. The introduction analyzes the problem of corporate data protection. The prospects of using the mechanisms of biometric voice and visual identification of subjects for its solution are substantiated. Biometric identification algorithms are investigated. The first section describes the existing algorithms for recognizing visual and voice images. The second section investigates the feasibility of using existing algorithms for voice and visual biometric identification, analyzes and compares existing image recognition architectures. The third section describes the process of developing algorithms for visual and voice biometric user identification The fourth section presents the characteristics of the developed COP, the test results, the system is studied on different data sets, and its modification in order to achieve the specified accuracy. The conclusions summarize the results of research and development.
25
Patino, Villar José María. "Efficient speaker diarization and low-latency speaker spotting". Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS003/document.
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La segmentation et le regroupement en locuteurs (SRL) impliquent la détection des locuteurs dans un flux audio et les intervalles pendant lesquels chaque locuteur est actif, c'est-à-dire la détermination de ‘qui parle quand’. La première partie des travaux présentés dans cette thèse exploite une approche de modélisation du locuteur utilisant des clés binaires (BKs) comme solution à la SRL. La modélisation BK est efficace et fonctionne sans données d'entraînement externes, car elle utilise uniquement des données de test. Les contributions présentées incluent l'extraction des BKs basée sur l'analyse spectrale multi-résolution, la détection explicite des changements de locuteurs utilisant les BKs, ainsi que les techniques de fusion SRL qui combinent les avantages des BKs et des solutions basées sur un apprentissage approfondi. La tâche de la SRL est étroitement liée à celle de la reconnaissance ou de la détection du locuteur, qui consiste à comparer deux segments de parole et à déterminer s'ils ont été prononcés par le même locuteur ou non. Même si de nombreuses applications pratiques nécessitent leur combinaison, les deux tâches sont traditionnellement exécutées indépendamment l'une de l'autre. La deuxième partie de cette thèse porte sur une application où les solutions de SRL et de reconnaissance des locuteurs sont réunies. La nouvelle tâche, appelée détection de locuteurs à faible latence, consiste à détecter rapidement les locuteurs connus dans des flux audio à locuteurs multiples. Il s'agit de repenser la SRL en ligne et la manière dont les sous-systèmes de SRL et de détection devraient être combinés au mieuxSpeaker diarization (SD) involves the detection of speakers within an audio stream and the intervals during which each speaker is active, i.e. the determination of ‘who spoken when’. The first part of the work presented in this thesis exploits an approach to speaker modelling involving binary keys (BKs) as a solution to SD. BK modelling is efficient and operates without external training data, as it operates using test data alone. The presented contributions include the extraction of BKs based on multi-resolution spectral analysis, the explicit detection of speaker changes using BKs, as well as SD fusion techniques that combine the benefits of both BK and deep learning based solutions. The SD task is closely linked to that of speaker recognition or detection, which involves the comparison of two speech segments and the determination of whether or not they were uttered by the same speaker. Even if many practical applications require their combination, the two tasks are traditionally tackled independently from each other. The second part of this thesis considers an application where SD and speaker recognition solutions are brought together. The new task, coined low latency speaker spotting (LLSS), involves the rapid detection of known speakers within multi-speaker audio streams. It involves the re-thinking of online diarization and the manner by which diarization and detection sub-systems should best be combined
26
Sanderson, Conrad. "Automatic Person Verification Using Speech and Face Information". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367191.
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Identity verification systems are an important part of our every day life. A typical example is the Automatic Teller Machine (ATM) which employs a simple identity verification scheme: the user is asked to enter their secret password after inserting their ATM card; if the password matches the one prescribed to the card, the user is allowed access to their bank account. This scheme suffers from a major drawback: only the validity of the combination of a certain possession (the ATM card) and certain knowledge (the password) is verified. The ATM card can be lost or stolen, and the password can be compromised. Thus new verification methods have emerged, where the password has either been replaced by, or used in addition to, biometrics such as the person’s speech, face image or fingerprints. Apart from the ATM example described above, biometrics can be applied to other areas, such as telephone & internet based banking, airline reservations & check-in, as well as forensic work and law enforcement applications. Biometric systems based on face images and/or speech signals have been shown to be quite effective. However, their performance easily degrades in the presence of a mismatch between training and testing conditions. For speech based systems this is usually in the form of channel distortion and/or ambient noise; for face based systems it can be in the form of a change in the illumination direction. A system which uses more than one biometric at the same time is known as a multi-modal verification system; it is often comprised of several modality experts and a decision stage. Since a multi-modal system uses complimentary discriminative information, lower error rates can be achieved; moreover, such a system can also be more robust, since the contribution of the modality affected by environmental conditions can be decreased. This thesis makes several contributions aimed at increasing the robustness of single- and multi-modal verification systems. Some of the major contributions are listed below. The robustness of a speech based system to ambient noise is increased by using Maximum Auto-Correlation Value (MACV) features, which utilize information from the source part of the speech signal. A new facial feature extraction technique is proposed (termed DCT-mod2), which utilizes polynomial coefficients derived from 2D Discrete Cosine Transform (DCT) coefficients of spatially neighbouring blocks. The DCT-mod2 features are shown to be robust to an illumination direction change as well as being over 80 times quicker to compute than 2D Gabor wavelet derived features. The fragility of Principal Component Analysis (PCA) derived features to an illumination direction change is solved by introducing a pre-processing step utilizing the DCT-mod2 feature extraction. We show that the enhanced PCA technique retains all the positive aspects of traditional PCA (that is, robustness to compression artefacts and white Gaussian noise) while also being robust to the illumination direction change. Several new methods, for use in fusion of speech and face information under noisy conditions, are proposed; these include a weight adjustment procedure, which explicitly measures the quality of the speech signal, and a decision stage comprised of a structurally noise resistant piece-wise linear classifier, which attempts to minimize the effects of noisy conditions via structural constraints on the decision boundary.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Microelectronic Engineering
Full Text
27
Saint-Lu, Nathalie. "Identification et caractérisation de formulations d'allergènes pour l'immunothérapie par voie sublinguale". Paris 11, 2009. http://www.theses.fr/2009PA11T034.
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Koc, Turgay. "Nonlinear Interactive Source-filter Model For Voiced Speech". Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615159/index.pdf.
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The linear source-filter model (LSFM) has been used as a primary model for speech processing
since 1960 when G. Fant presented acoustic speech production theory. It assumes
that the source of voiced speech sounds, glottal flow, is independent of the filter, vocal tract.
However, acoustic simulations based on the physical speech production models show that,
especially when the fundamental frequency (F0) of source harmonics approaches to the first
formant frequency (F1) of vocal tract filter, the filter has significant effects on the source due
to the nonlinear coupling between them. In this thesis, as an alternative to linear source-filter
model, nonlinear interactive source-filter models are proposed for voiced speech.
This thesis has two parts, in the first part, a framework for the coupling of the source and the
filter is presented. Then, two interactive system models are proposed assuming that glottal
flow is a quasi-steady Bernoulli flow and acoustics in vocal tract is linear. In these models,
instead of glottal flow, glottal area is used as a source for voiced speech. In the proposed interactive
models, the relation between the glottal flow, glottal area and vocal tract is determined
by the quasi-steady Bernoulli flow equation. It is theoretically shown that linear source-filter
model is an approximation of the nonlinear models. Estimation of ISFM&rsquos parameters from only speech signal is a nonlinear blind deconvolution problem. The problem is solved by a robust method developed based on the acoustical interpretation of the systems. Experimental results show that ISFMs produce source-filter coupling effects seen in the physical simulations and the parameter estimation method produce always stable and better performing models than LSFM model. In addition, a framework for the incorporation of the source-filter interaction into classical source-filter model is presented. The Rosenberg source model is extended to an interactive source for voiced speech and its performance is evaluated on a large speech database. The results of the experiments conducted on vowels in the database show that the interactive Rosenberg model is always better than its noninteractive version. In the second part of the thesis, LSFM and ISFMs are compared by using not only the speech signal but also HSV (High Speed Endocopic Video) of vocal folds in a system identification approach. In this case, HSV and speech are used as a reference input-output data for the analysis and comparison of the models. First, a new robust HSV processing algorithm is developed and applied on HSV images to extract the glottal area. Then, system parameters are estimated by using a modified version of the method proposed in the first part. The experimental results show that speech signal can contain some harmonics of the fundamental frequency of the glottal area other than those contained in the glottal area signal. Proposed nonlinear interactive source-filter models can generate harmonics components in speech and produce more realistic speech sounds than LSFM.
29
Faresse, Nourdine. "Identification de PCTA, un nouvel effecteur de la voie de signalisation du TGF-beta". Paris 6, 2007. http://www.theses.fr/2007PA066428.
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La stimulation des cellules au TGF- entraîne l’assemblage des protéines cytoplasmiques Smad2/3 avec Smad4. Ce complexe activé se transloque dans le noyau et régule la transcription des gènes cibles du TGF-. Dans le noyau, le complexe Smad peut soit recruter un co-répresseur tel que TGIF. Le TGIF peut inhiber la transcription dépendante du TGF- par différents mécanismes. Récemment, il a été démontré que le TGIF est capable de séquestrer la protéine cytoplasmique cPML dans le noyau inhibant ainsi la phosphorylation de Smad2/3. Dans cette étude, nous avons identifié un nouveau partenaire du TGIF que nous avons nommé PCTA (PML Competitor for TGIF Association). PCTA s’associe à TGIF dans les cellules de mammifères et cette association est stimulée par le TGF-. L’expression de PCTA stimule la transcription induite par le TGF-, une activité qui est due à l’inhibition de la séquestration nucléaire de cPML à travers une compétition de liaison au TGIF. Par ailleurs, nous avons démontré que la surexpression de PCTA peut inhiber la progression tumorale. Ces résultats nous permettent de classer PCTA comme une nouvelle protéine anti-tumorale effectrice de la voie du TGF-.
30
Triffaux, Emily. "Identification des canaux Cav1 impliqués dans la voie de signalisation calcique des lymphocytes Th2". Toulouse 3, 2013. http://thesesups.ups-tlse.fr/1959/.
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L'asthme est une maladie pulmonaire qui touche environ 10% de la population. Les lymphocytes T helper de type 2 jouent une rôle important dans la physiopathologie de l'asthme en produisant de l'interleukine 4,5,13. Mon équipe a montré dans une étude précédente que les cellules Th2 mais pas Th1 de souris exprimaient des canaux CaV1. Un oligonucléotide antisens (CaV1AS) inhibe la réponse calcique et la production de cytokines Th2 sous stimulation par le TCR sans toucher les cellules Th1 chez la souris. De plus, CaV1AS prévient l'asthme allergique expérimental. Durant ma thèse, j'ai montré que les cellules T au repos expriment CaV1. 4. Les isoformes CaV1. 2 et CaV1. 3 prédominent dans les cellules Th2 et leur expression est perdue dans les Th1. Un inhibiteur pharmacologique des canaux CaV1, un CaV1AS et CaVbAS diminue l'expression protéique de CaV1. 2 suggérant que CaVb est requis pour la stabilité des lymphocytes Th2. Finalement, l'inhibition de la PKCa/b diminue la réponse calcique et la production de cytokines par les lymphocytes Th2 mais pas Th1 suggérant que la PKC pourrait contribuer à la régulation de CaV1 dans les lymphocytes Th2. Ces résultats suggèrent que la PKC pourrait contribuer à la régulation de CaV1 dans les lymphocytes Th2. Ces résultats suggèrent que l'inhibition des canaux CaV1. 2 pourrait être bénéfique dans les maladies allergiquesAsthma is an allergic pulmonary disease which affects around 10% of the population. Allergen-specific type 2 T helper lymphocytes Th2 have a crucial role in the asthma physiopathology by producing interleukin IL4,5,13. Previously, my team reported that mouse Th2 but not Th1 cells express voltage gated calcium CaV1 channels. CaV1 channel specific antisense oligonucleotide CaV1AS inhibit calcium response and Th2 cytokine production (IL4,5,13) upon TCR stimulation without any effect on Th1 cells in mice. In addition, CaV1AS prevent experimental allergic asthma. During my PhD, I showed the CaV1. 4 expression in human resting cells. Conversely, CaV1. 2 and CaV1. 3 predominated in Th2 cells and were lost in Th1 cells. CaV1 channel inhibitors, CaV1. 2 AS and CaVbAS decreased calcium signaling and cytokine production in Th2 but not in Th1 cells. Moreover, CaVbAS decrease the CaV1. 2 protein suggesting that CaVb is required for CaV1. 2 stability in Th2 cells. Finally selective PKCa/b inhibition decreased calcium response and cytokine production by Th2 but not Th1 cells suggesting that PKC may contribute to CaV1 regulation in Th2 cells. These results suggest that the inhibition of CaV1. 2 channels could be beneficial in allergic diseases while sparing Th1 cell responses
31
Zablocki, Laurent. "Identification de facteurs de régulation de la voie de signalisation TLR3 par crible génétique". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS533.
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La défense de l’organisme contre des pathogènes passe par la détection de motifs moléculaires spécifiques de ces derniers. Dans l’arsenal de récepteurs capables de reconnaître ces motifs figure la famille des Toll-like receptors (TLR) endosomaux, spécifiques d’acides nucléiques. Parmi eux, TLR3 détecte la présence anormale d'ARN double brin dans les endosomes et initie une forte réponse immunitaire innée. Cependant, la régulation de TLR3 reste encore mal comprise. Pour identifier de nouveaux acteurs moléculaires impliqués dans la voie TLR3, nous avons réalisé un crible à l'échelle du génome en utilisant la technologie CRISPR / Cas9. Nous avons développé une lignée de cellules rapporteuses de la voie TLR3, puis générés des mutants en transduisant ces cellules avec une banque d’ARNg. Les cellules ont ensuite été soumises à des cycles de stimulation par du poly (I:C) suivi de tri des cellules GFP-. L’enrichissement de certains ARNg au sein de la population triée, souligne l’importance des gènes correspondant dans la voie TLR3. Cinq gènes, dont TLR3, connu pour être nécessaire à la voie de TLR3, ont été identifiés par le crible, validant ainsi notre stratégie. Nous avons étudié les 40 meilleurs candidats issus du crible. Parmi les candidats confirmés, nous nous sommes concentrés sur AhR (récepteur d’aryl d’hydrocarbone). En l’absence d’AhR la réponse médiée par TLR3 est impactée de deux manières avec une perte de production d'IL-8 et une augmentation de celle d'IP-10. Dans les macrophages humains primaires exposés au poly(I:C), l’activation d’AhR améliore la production d’IL-8 et inhibe celle d’IP-10. Ainsi, AhR semble capable de moduler la réponse du TLR3The fight of the organism against pathogens involves the detection of molecular patterns that are conserved among pathogens. Among the arsenal of receptors capable of recognizing these patterns, there is the family of endosomal Toll-like receptors (TLRs) that are specific for nucleic acids. Among them, TLR3 senses the abnormal presence of double-stranded RNA in the endosomes and initiates a potent innate immune response. Nevertheless, mechanisms governing TLR3 regulation still remain poorly understood. To identify new molecular players involved in the TLR3 pathway, we performed a genome-wide screen using the CRISPR/Cas9 technology using reporter cells expressing GFP when stimulated via TLR3. Mutagenesis was achieved by transducing these cells with the lentiviral GeCKO v2 sgRNA library. Cells were then subjected to sequential rounds of stimulation with poly(I:C) and sorting of the GFP- cells. Enrichments in sgRNA estimated by deep-sequencing identified genes required for TLR3-induced activation of NF-κB. Five genes, including TLR3 itself and the chaperone UNC93B1, known to be critically involved in the TLR3 pathway, were identified by the screen, thus validating our strategy. We further studied the best 40 hits. Among the hits confirmed, we focused on AhR (aryl hydrocarbon receptor). Depletion of AhR had a dual effect on the TLR3 response, abrogating the IL-8 production and enhancing the IP-10 release. Interestingly, in primary human macrophages exposed to poly(I:C), AhR activation enhanced IL-8 and inhibited the IP-10 one. Overall, AhR appears able to modulate the TLR3 response
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Bouvard, Daniel. "Identification d'une voie de signalisation controlant l'adhérence cellulaire dépendante de l'intégrine [alpha]5[bêta]1". Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10158.
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Les integrines appartiennent a une grande famille de recepteurs heterodimeriques transmembranaires de type i impliques dans l'interaction des cellules entres elles ou a la matrice extracellulaire. Les signaux emis lors de l'engagement des integrines permettent le controle de nombreux processus cellulaires comme la migration, l'adherence, la proliferation, la differentiation ou encore l'apoptose. L'interaction des integrines avec leur ligand extracellulaire peut etre controlee depuis l'interieur de la cellule. Dans cette derniere regulation, le domaine cytoplasmique joue un role essentiel en interagissant avec des proteines intracellulaires. Dans la premiere partie de ce travail, j'ai pu montrer que la proteine kinase dependante du calcium et de la calmoduline de type ii (camkii) etait impliquee dans le controle de l'affinite de l'integrine 51. En effet, l'augmentation de l'activite de la camkii inhibe, in vitro, l'interaction entre l'integrine et la fibronectine. Ex vivo, l'inhibition de cette proteine kinase se traduit par une stimulation significative de l'etalement cellulaire en condition limitante de fibronectine. Par contre, l'expression ectopique de la camkii constitutivement active dans les cellules cho inhibe fortement leur etalement. Dans un second temps, j'ai etudie l'implication potentielle de la proteine icap-1 (integrin cytoplasmic domain associated protein-1) dans cette voie de regulation. Des mutations, au niveau du site potentiel de phosphorylation pour la camkii, abolissant ou au contraire mimant la phosphorylation perturbent severement l'etalement des cellules. Ceci montre que la proteine icap-1 et la camkii regulent l'etalement cellulaire dependant de l'integrine 51. Enfin, une approche moleculaire de l'action d'icap-1 a ete entreprise. Apres avoir confirme une interaction specifique entre la proteine icap-1 et l'integrine 51, j'ai analyse la localisation sub-cellulaire d'icap-1 a l'aide d'anticorps developpes au laboratoire. Aucune localisation de la proteine dans les adherences focales n'a pu etre mis en evidence. Par contre, la fixation d'icap-1 sur le domaine cytoplasmique des integrines a sous-unite 1 inhibe non seulement la fixation de la taline mais aussi le recrutement de proteines localisees dans les adherences focales. De ce fait, icap-1 pourrait etre un nouveau regulateur de la fonction adhesive des integrines.
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Khater, Fida. "Identification et validation fonctionnelle de nouveaux gènes impliqués dans la voie de biosynthèse des composés phénoliques". Thesis, Montpellier, SupAgro, 2011. http://www.theses.fr/2011NSAM0018/document.
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Les proanthocyanidines (PA) du raisin jouent un rôle majeur dans les propriétés organoleptiques du vin notamment dans l'astringence et la stabilité de la couleur. Elles sont accumulées principalement dans la pellicule et les pépins pendant les premiers stades du développement de la baie. La biosynthèse des PA commence à être bien décrite, cependant certaines étapes restent à élucider.Une étude transcriptomic avait permis d'indentifier de nouveaux gènes potentiellemnt impliqués dans la biosynthèse des PA (Terrier et al., 2009). Parmi ces gènes figuraient 3 glucosyltransférases et 2 glucose- acyltransférases.Les trois glucosyltransférases VvgGT1, VvgGT2 et VvgGT3 présentent de fortes homologies entres elles et avec d'autres glucosyltransférases capables de catalyser la formation de glucose ester. Les transcrits sont exprimés durant les premiers stades de développement de la baie principalement dans les pépins et la pellicule mais aussi dans la pulpe pour VvgGT2. Les propriétés de ces 3 enzymes (Km, Vm, spécificité de substrat, effet du pH) ont été étudiées in vitro après production de protéines recombinantes. Les 3 VvgGTs sont capables de catalyser la synthèse d'esters de glucose en présence de dérivés d'acide hydroxybenzoique ou d'acide hydroxycinnamique.Deux acyltransférases VvGAT1 et VvGAT2 ont été isolées. Elle présente de fortes similarités avec des acyltransférases glucose-ester dépendantes de type serine carboxypeptidase like. Les transcrits sont exprimés surtout avant la véraison, dans les pépins et la pellicule pour VvGAT1 et dans la pulpe et les pépins pour la VvGAT2. L'expression hétérologue dans différents hôtes n'a pas permis de détecter d'activité enzymatique. Les analyses en microscopie confocale suggèrent que VvGAT1 fusionnée à une GFP est localisée dans des vésicules cytoplasmiques.L'implication successive des VvgGTs et des VvGATs dans la galloylation des PA et dans la synthèse d'esters d'acides hydroxcinnamiques est discutéeGrape proanthocyanidins (PA) play a major role in organoleptic properties of wine, being involved in astringency and color stability. They are accumulated mainly in skin and seeds during early stages of berry development. Numerous structural genes involved in PA biosynthesis have already been identified even in grape, but some steps are still not documented.A previous transcriptomic study led to identify new genes putatively involved in the PA pathway (Terrier et al., 2009). Among them, 3 glucosyltransferases and 2 glucose acyl transferases were identified. The objective of this work is to clarify the function of these genes in the phenylpropanoid pathway.The three glucosyltransferases called VvgGT1, VvgGT2, VvgGT3 displayed high sequence similarities between them and with other plant glucosyltransferases able to catalyze the formation of glucose esters. The transcripts are expressed in the early stages of grape berry development, mainly in skins and seeds and also in the pulp for VvgGT2. The properties of these 3 enzymes (Km, Vm, substrate specificity, pH sensitivity) were studied in vitro after production of recombinant proteins. The three of them are able to catalyse the synthesis of glucose ester with derivates of hydroxybenzoic acids and hydroxycinnamic acids as substrates and with similar kinetic properties.Two glucose-acyltransferases called VvGAT1 and VvGAT2 were isolated. They displayed high sequence similarity with other Serine carboxypeptidase like acyltransferases-glucose dependent. The transcripts are expressed in early stages of grape berry development mainly in skins and seeds for VvGAT1 and in pulp and seeds for VvGAT2. Heterologous expression of the proteins in different hosts were unsuccessful. The confocal microscopy data suggest that VvGAT1 fused to GFP are localized in cytosolic vesicles.The successive involvement of those VvgGT and VvGAT in the galloylation of PAs and in the synthesis of hydroxycinnamic esters is discussed
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Rondeau, Evelyne. "Identification d'interacteurs moléculaires et génétiques des argonautes impliqués dans la voie des microARN chez C. Elegans". Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25600/25600.pdf.
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Chez les eucaryotes, les microARN sont de courts ARN non codants régulant les gènes essentiels pour le développement et la différenciation cellulaire. Parmi les facteurs cellulaires clés de cette voie métabolique, on retrouve les RNAses de type III Drosha et Dicer, ainsi que les protéines Argonautes ALG-1 et ALG-2 chez C. elegans. Dans le but de mieux caractériser l’implication des protéines Argonautes dans la voie des microARN, nous avons utilisé deux approches différentes. Premièrement, nous avons étudié la liaison de la protéine Argonaute ALG-1 aux microARN chez C. elegans en fonction du stade développemental, et ce par analyse par micropuce des microARN associés avec ALG-1. Cette étude nous a permis de remarquer que ALG-1 lie la majorité des microARN, mais non la totalité, et ce, de façon très importante aux stades développementaux tardifs. Deuxièmement, nous nous sommes intéressés à l’identification d’interacteurs génétiques d’alg-2. Nous avons donc réalisé un criblage génétique basé sur la létalité synthétique avec le gène alg-2. Ainsi, lorsque le gène synthétique létal est muté simultanément avec alg-2, tel qu’observé avec alg-1, la double lésion induit la mort de l’animal. De ce criblage, nous avons isolé 11 mutants, classés en 5 groupes de complémentation. Par l’utilisation de techniques de cartographie génétique, nous avons localisé la mutation chez le candidat sla-1 sur le chromosome V, entre les positions génétiques de -12.7 et -3.65.In eukaryotes, microRNAs are small non-coding RNAs which have the role of regulating genes essential for development and cellular differentiation. Beside the RNAse III family members (Drosha and Dicer) and the Argonaute proteins ALG-1 and ALG-2 in C. elegans, essential components of this gene regulation pathway are still not uncovered. In order to characterize the implication of Argonaute proteins ALG-1 and ALG-2 in microRNA pathway, we used two approaches. First, we studied the interaction between microRNA and ALG-1 during worm development by microarray analysis of microRNA associated to ALG-1. From this analysis, we observed that the majority, but not the totality, of microRNA are associated to ALG-1, mostly at early developmental stages. Secondly, to identify new components of microRNA pathway, we conducted a genetic screen to identify new interactors of alg-2. Our screen is based on the synthetic lethality feature of alg-2 and alg-1 genes. In absence of both genes, the animal can not survive. With this synthetic lethal screen, we want to identify new genes that work in synergy with alg-2, like alg-1, interacting in the same genetic pathway. The worms have been mutagenized and 11 mutants, classified in 5 complementation groups, have been collected. By using various mapping techniques, we localized the mutation on mutant sla-1(qbc1) on chromosome V, between the genetic positions of -12.7 and -3.65.
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Saraswathy, Vishnu. "Identification d’un nouveau rôle de la E3-ubiquitin ligase Mindbomb1 dans la voie Polarité Cellulaire Planaire". Electronic Thesis or Diss., Université Côte d'Azur (ComUE), 2019. http://theses.univ-cotedazur.fr/2019AZUR6000.
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La morphogenèse est le processus qui définit la forme d'un organisme (ou d'une partie d'un organisme) nécessaire à son bon fonctionnement. Au cours de l'embryogenèse, la morphogenèse d'un organe nécessite des processus incluant la division cellulaire, les mouvements cellulaires et la différenciation cellulaire. Cependant, on sait peu de choses sur la façon dont ces différents processus sont coordonnés au cours de la morphogenèse d'un organe. Au cours de ma thèse, j'ai étudié deux voies de signalisation cellulaire différentes qui régulent la morphogenèse au cours de l'embryogenèse du poisson zèbre. Mon étude a révélé que la voie de signalisation Notch et la voie PCP (Polarité Cellulaire Planaire) contrôlée par Mib1 régulent respectivement la morphogenèse du tube neural et l'extension de l'axe embryonnaire.Au cours de la première partie de ma thèse, j'ai étudié le rôle de la signalisation de Notch dans la morphogenèse du tube neural du poisson zèbre. La signalisation Notch a déjà été bien étudiée pour son rôle dans la régulation de la neurogenèse lors du développement du poisson zèbre. Cependant, on ne sait pas si et comment la signalisation Notch régule la morphogenèse du tube neural du poisson zèbre. L'épithélialisation et la c-division sont des événements importants au cours de la morphogenèse du tube neural du poisson zèbre. Nos résultats montrent que, en plus de synchroniser la spécification des cellules neuronales, la suppression de la neurogenèse induite par Notch est essentielle pour l’acquisition de l’architecture neuroépithéliale et pour la réalisation de c-division. Ainsi, la signalisation Notch permet de former la moelle épinière de poisson zèbre.Les observations de la première partie de ma thèse ont conduit à l'identification du rôle de Mindbomb1 (Mib1) dans la signalisation PCP. Mib1, une ligase ubiquitine-E3 nécessaire à l'activation de Notch, régule les mouvements d'extension convergence (CE) nécessaires à l'élongation de l'axe de l'embryon au cours de la gastrulation du poisson zèbre. De manière intéressante, nous avons montré que Mib1, indépendamment de sa fonction dans la signalisation Notch, agit dans la voie PCP pour réguler l’extension de l’axe de l’embryon. Dans la voie de la PCP, Mib1 agit comme une ligase ubiquitine-E3 et régule l'endocytose du composant de la PCP Ryk afin d'assurer la médiation de la CE lors de la gastrulation. Ainsi, notre étude a révélé que, indépendamment de son rôle dans la signalisation Delta / Notch, Mib1 est important pour la voie PCP lors de la gastrulation du poisson zèbreDuring my PhD, I studied two different cell signaling pathways that regulate morphogenesis during zebrafish development. I found that the Notch signaling pathway and Mib1 mediated Planar Cell Polarity (PCP) pathway regulate neural tube morphogenesis and embryonic axis extension respectively.During the first part of my PhD, I addressed the role of Notch signaling in zebrafish neural tube morphogenesis. Notch signaling has been well studied for its role in regulating neurogenesis during zebrafish development. However, whether and how it regulates morphogenesis of the zebrafish neural tube is unknown. Epithelialization and c-division are important events during zebrafish neural tube morphogenesis. Our findings show that, in addition to regulating the timing and identity of neuronal cell fate specification, Notch mediated suppression of neurogenesis is essential for the acquisition of polarized neuroepithelial tissue architecture and the execution specific morphogenetic movements called c-divisions, in order to properly shape the zebrafish spinal cord. Observations from the first part of my PhD led to the identification of the role of Mindbomb1(Mib1) in PCP signaling. Mib1, an E3-ubiquitin ligase required for Notch activation, regulates convergent extension (CE) movements during zebrafish gastrulation, that are required for the axis elongation of the embryo. Interestingly, I found that Mib1, independent of its function in Notch signaling, act in the PCP pathway to regulate axis extension. In the PCP pathway, Mib1 acts as an E3-ubiquitin ligase and regulates endocytosis of the PCP component Ryk to mediate CE during gastrulation. Thus, my study discovered that independent of its role in Delta/Notch signaling, Mib1 is important for the PCP pathway during zebrafish gastrulation
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Mekyska, Jiří. "Identifikace osob pomocí otisku hlasu". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218235.
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This work deals with the text-dependent speaker recognition in systems, where just a few training samples exist. For the purpose of this recognition, the voice imprint based on different features (e.g. MFCC, PLP, ACW etc.) is proposed. At the beginning, there is described the way, how the speech signal is produced. Some speech characteristics important for speaker recognition are also mentioned. The next part of work deals with the speech signal analysis. There is mentioned the preprocessing and also the feature extraction methods. The following part describes the process of speaker recognition and mentions the evaluation of the used methods: speaker identification and verification. Last theoretically based part of work deals with the classifiers which are suitable for the text-dependent recognition. The classifiers based on fractional distances, dynamic time warping, dispersion matching and vector quantization are mentioned. This work continues by design and realization of system, which evaluates all described classifiers for voice imprint based on different features.
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Hichri, Imène. "Identification et caractérisation fonctionnelle de gènes régulateurs de la voie de biosynthèse des flavonoïdes chez la Vigne". Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13875/document.
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Les composés phénoliques de la baie, et plus particulièrement les flavonoïdes (flavonols, tanins condensés, anthocyanes), constituent un des paramètres clés contrôlant la qualité organoleptique du raisin et du vin. Ils représentent également une source de molécules antioxydantes d’intérêt grandissant pour les industries pharmacologiques, agro-alimentaires et cosmétiques. De nombreux travaux réalisés sur les plantes modèles ont démontré que la régulation de la voie de biosynthèse des flavonoïdes est essentiellement gouvernée par des facteurs de transcription de type MYB, bHLH et des protéines de type WD40. Chez la Vigne (Vitis vinifera L.), plusieurs facteurs de transcription de type MYB régulant la voie des anthocyanes et/ou des tanins condensés ont déjà été identifiés. Cependant, aucun facteur de transcription de type bHLH ou WD40 n’a encore été caractérisé. Différentes approches ont été mises en œuvre pour identifier de nouveaux régulateurs de la voie des flavonoïdes chez la Vigne. Dans un premier temps, le facteur de transcription VvMYB5b a été utilisé comme appât dans une approche de double hybride non ciblé chez la Levure (Saccharomyces cerevisiae). Dans un deuxième temps, le promoteur d’un gène codant une enzyme centrale de la voie de biosynthèse des flavonoïdes, VvDFR, a été choisi afin de développer une approche de simple hybride non ciblé chez la Levure. Enfin, une approche ciblée vers des « gènes candidats » a permis l’identification des facteurs de transcription de type bHLH VvMYC1 et VvMYCA1. Le profil d’expression de VvMYCA1 correspond à celui de l’accumulation des tanins condensés dans la pellicule, et celui de VvMYC1 corrèle avec le profil de synthèse des flavonols, des anthocyanes et des tanins condensés dans la baie de raisin, ainsi que dans les inflorescences. De plus, VvMYC1 peut interagir avec différents partenaires MYB de Vigne régulant la synthèse des anthocyanes et/ou des tanins condensés, à la fois dans la Levure mais également in planta, où l’interaction VvMYC1/VvMYBs affecte l’expression de gènes structuraux tels que l’UFGT et l’ANR. Cette interaction induit une synthèse d’anthocyanes, aussi bien en système homologue qu’en système hétérologue (Tabac et Arabidopsis). Enfin, des essais complémentaires impliquant le promoteur de VvMYC1 ont permis de démontrer que VvMYC1, en interagissant avec VvMYBPA1, peut moduler sa propre expression in vivoPhenolic compounds, and more specifically flavonoids (flavonols, condensed tannins and anthocyanins), are key components of the grapevine and wine quality. Because of their antioxidant activities, these compounds are of interest in pharmacological and cosmetic industries, as well as being beneficial to the human diet. Previous work on model plants showed that the flavonoid pathway was mainly regulated by the MYB and bHLH transcription factors, and WD40 proteins. In the grapevine (Vitis vinifera L.), only MYB regulators have been identified until now, and no bHLH or WD40 have been characterised. In this work, several approaches were used to identify new transcription factors involved in grapevine flavonoid biosynthesis. Firstly, the VvMYB5b protein was used as a bait in a large scale two hybrid experiment in yeast (Saccharomyces cerevisiae). Secondly, the promoter of the VvDFR gene, coding a central enzyme of the flavonoid pathway, was chosen to conduct a large scale one hybrid experiment, also in yeast. Finally, a “gene candidate” approach allowed identification of the bHLH transcription factors VvMYC1 and VvMYCA1. VvMYCA1 expression profile in berry skin and seeds correlates with condensed tannins synthesis, whereas VvMYC1 transcript accumulation in these tissues and the grapevine inflorescence correlates with condensed tannins, anthocyanins and flavonols accumulation. In yeast, VvMYC1 could physically interact with different MYB partners regulating the anthocyanin or the condensed tannins biosynthesis. This interaction was confirmed by transient promoter assays in grape cell suspensions, where co-expression of VvMYC1 with specific MYB partners activated the UFGT and ANR promoters. Likewise, this interaction induced anthocyanin accumulation in grape cells, as well as in tobacco leaves and Arabidopsis. Eventually, additional transient promoter assays revealed that VvMYC1 is involved, with VvMYBPA1, in feedback regulation of its own expression
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Khatami, Iman. "Free-field inlet / outlet noise identification on aircraft engines using microphones array". Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/7581.
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Abstract : This thesis considers the discrimination of inlet / exhaust noise of aero-engines in free-field static tests using far-field microphone arrays. Various techniques are compared for this problem, including classical beamforming (CB), regularized inverse method (Tikhonov regularization), LI - generalized inverse beamforming (LI-GIB), clean-PSF, clean-SC and two novel methods which are called hybrid method and clean-hybrid. The classical beamforming method is disadvantaged due to its need for a high number of measurement microphones in accordance with the requirements. Similarly, the inverse method is disadvantaged due to their need of having a priori source information. The classical Tikhonov regularization provides improvements in solution stability, however continues to be disadvantaged due to its requirement of imposing a stronger penalty for undetected source positions. Coherent and incoherent sources are resolved by LI-generalized inverse beamforming (L1-GIB). This algorithm can distinguish the multipole sources as well as the monopoles sources. However, source identification by LI-generalized inverse beamforming takes much time and requires a PC with high memory. The hybrid method is a new regularization method which involves the use of an a priori beamforming measurement to define a data-dependent discrete smoothing norm for the regularization of the inverse problem. Compared to the classical beamforming and the inverse modeling, the hybrid (beamforming regularization) approach provides improved source strength maps without substantial added complexity. Although the hybrid method rather solves the disadvantage of the former methods, the application of this method for identification of weaker sources in the presence of the strong sources isn't satisfactory. This can be explained by the large penalization being applied to the weaker source in the hybrid method, which results in underestimation of source strength for this source. To overcome this defect, the clean-SC method and the proposed clean-hybrid method, which is a combination of the hybrid method and the clean-SC, are applied. These methods remove the effect of the strong sources in source power maps to identify the weaker sources. The proposed methods which represent the main contribution of this thesis show promising results and opens new research avenues. Theoretical study of all approaches is performed for various sources and configurations of array. In order to validate the theoretical study, several laboratory experiments are conducted at Universito de Sherbrooke. The proposed methods have further been applied to the measured noise data from a Pratt & Whitney Canada turbo-fan engine and have been observed to provide better spatial resolution and solution robustness with a limited number of measurement microphones compared to the existing methods.Résumé : La présente thèse étudie la discrimination du bruit d'entrée / de sortie des moteurs d'avion dans des tests statiques en champ libre en utilisant des antennes de microphones en champ lointain. Diverses techniques sont comparées pour ce problème, dont la formation de voie classique (CB), la méthode inverse régularisée (régularisation de Tikhonov), la formation de voies généralisée inverse (L1-GIB), Clean-PSF, Clean-SC et deux méthodes proposées qui s'appellent la méthode hybride et la méthode Clean-hybride. La méthode la formation de voie classique est désavantagée en raison de son besoin de nombreux microphones de mesure. De même, la méthode inverse est désavantagée en raison du besoin d'information a priori sur les sources. La régularisation Tikhonov classique fournit des améliorations dans. la stabilité de la solution; cependant elle reste désavantageuse en raison de son exigence d'imposer une pénalité plus forte pour des positions de source non détectées. Des sources cohérentes et incohérentes peuvent être résolues par la formation de voies généralisée inverse (L1-GIB). Cet algorithme peut identifier les sources multi- polaires aussi bien que les sources monopolaires. Cependant, l'identification de source par la formation de voies généralisée inverse prend beaucoup de temps et exige un ordinateur avec une capacité de mémoire élevée. La méthode hybride est une nouvelle méthode de régularisation qui implique l'utilisation d'un traitement par formation de voie a priori pour définir une norme discrète et dépendante des données pour la régularisation du problème inverse. En comparaison avec la formation de voie classique et la méthode inverse, l'approche hybride (régularisation par formation de voie) fournit des cartographies améliorées d'amplitudes de sources sans aucune complexité supplémentaire substantielle. Bien que la méthode hybride lève les limitations des méthodes classiques, l'application de cette méthode pour l'identification de sources de faible puissance en présence de sources de forte puissance n'est pas satisfaisante. On peut expliquer ceci par la plus grande pénalisation appliquée à la source plus faible dans la méthode hybride, qui aboutit à la sous-estimation de l'amplitude de cette source. Pour surmonter ce défaut, la méthode Clean-SC et la méthode Clean-hybrides proposée qui est une combinaison de la méthode hybride et de Clean-SC sont appliquées. Ces méthodes éliminent l'effet des sources fortes dans les cartographies de puissance de sources pour identifier les sources plus faibles. Les méthodes proposées qui représentent la contribution principale de cette thèse conduisent à des résultats fiables et ouvrent des nouvelles voies de recherche. L'étude théorique de toutes les approches est menée pour divers types de sources et de configurations microphoniques. Pour valider l'étude théorique, plusieurs expériences en laboratoire sont réalisées à Université de Sherbrooke. Les méthodes proposées ont été appliquées aux données de bruit mesurées d'une turbo-soufflante Pratt & Whitney Canada pour fournir une meilleure résolution spatiale des sources acoustique et une solution robuste avec un nombre limité des microphones de mesure comparé aux méthodes existantes.
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Giguère, Nellie. "Identification de partenaires potentiels de la protéine ALG-1 : découverte de nouveau joueurs dans la voie des microARNs". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27755/27755.pdf.
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Ginis, Olivia. "Identification de facteurs de transcription régulateurs de la voie de biosynthèse des alcaloïdes indoliques monoterpéniques chez Catharanthus roseus". Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4014/document.
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Catharanthus roseus est une plante tropicale qui produit spécifiquement des alcaloïdes indoliques monoterpéniques (AIM) d’intérêt thérapeutique. Chez C. roseus, la branche terpénique incluant la voie du méthylérythritol phosphate (MEP) est considérée comme limitante et présente une régulation transcriptionnelle coordonnée en réponse aux hormones inductrices de l’accumulation alcaloïdique. Lors de ce travail, suite à des analyses bioinformatiques et à la caractérisation de promoteurs de gènes de la voie MEP, nous avons identifié de nouvelles familles de facteurs de transcription impliquées dans la régulation de la biosynthèse des AIM. Des membres de la famille des ZCT, des WRKY et des RR type B interagissent avec le promoteur du gène hds de la voie MEP et régulent son activité. Ces travaux ont permis d’approfondir les connaissances sur les réseaux transcriptionnels régulateurs de la biosynthèse des AIM. L’utilisation de ces nouveaux facteurs de transcription activateurs peut désormais être envisagée dans le cadre d’expériences d’ingénierie métabolique afin d’augmenter l’accumulation d’alcaloïdes d’intérêt pharmaceutique chez C. roseusCatharanthus roseus is a tropical plant producing specifically monoterpene indole alkaloids (MIA) of high interest due to their therapeutical values. In C. roseus cells, the terpenoid branch including the methyl erythritol phosphate pathway (MEP) provides the MIA terpenoid moiety and is regarded as limited for MIA biosynthesis. This branch presents a coordinated transcriptional regulation in response to hormonal signals leading to MIA production. In this context, bioinformatic analysises and functional characterization of MEP pathway gene promoters allowed the identification of new transcription factor families involved in the MIA pathway regulation. Members of ZCT proteins, WRKY and type B RR families specifically interact with the hds promoter from the MEP pathway and regulate its activity. This work permits to gain into insight the transcriptional network controlling the MIA biosynthesis. It is possible now to consider using transcription factor that act as activators and target genes from the terpenoid branch to increase the accumulation of alkaloids of pharmaceutical interest in C. roseus by metabolic engineering approaches
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Vatinel, Sébastien. "Identification de nouveaux partenaires du récepteur CCK2 : rôle de la phosphophatase SHP2 dans l'activation de la voie Akt". Toulouse 3, 2006. http://www.theses.fr/2006TOU30215.
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Belzacq, Anne-Sophie. "La voie mitochondriale de l'apoptose, identification d'une nouvelle cible thérapeutique potentielle : le translocateur de nucléotides à adénine (ANT)". Compiègne, 2002. http://www.theses.fr/2002COMP1408.
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La mitochondrie a longtemps été considérée comme un simple producteur d’énergie cellulaire. Cependant, son implication dans la régulation de l’apoptose en tant qu’intégrateur des voies de mort cellulaire et exécuteur de la sentence létale est désormais établie. En effet, de nombreuses molècules pro-apoptotiques agissent sur la mitochondrie et induisent la perméabilisation des membranes mitochondriales (PMM). L’altération de la perméabilité des membranes mitochondriales représentent le point de non-retour dans la cascade évènementielle du processus de mort cellulaire. Cette PMM impliquerait l’ouverture d’un complexe polyprotéique mitochondrial appelé pore de transition de perméabilité (PTPC). Le translocateur de nucléotides à adénine (ANT) est un des constituant dans la voie mitochondriale de l’apoptose. Nous avons développé des test de criblage basés sur la reconstitution en liposomes d’ANT purifié, afin d’étudier sa fonctionnalité et son implication dans la perméabilisation des membranes. Nous avons ainsi montré que l’ANT se comporte comme une protéine bi-fonctionnelle régulée par les oncogènes de la famille de Bax/Bcl-2 : celle-ci assure, d’une part, une étape cruciales du métabolisme oxydatif, la translocation d’ADP/ATP, et d’autre part, peut être convertie en pore non spécifique proapoptose. De plus, l’ANT est la cible de multiples inducteurs endogènes ou exogènes d’apoptose et semble donc constituer une cible thérapeutique potentielle dans le traitement des diverses pathologies consécutives à des dérèglements d’apoptose.
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Vialart, Guilhem. "Identification et caractérisation fonctionnelle de gènes impliqués dans la voie de biosynthèse des furocoumarines chez les végétaux supérieurs". Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0390/document.
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Les furocoumarines sont des métabolites secondaires qui dérivent de la voie de biosynthèse des phénylpropanoïdes. Ces phytoalexines interviennent notamment dans les mécanismes de défense des plantes tels que la résistance aux bioagresseurs. Le déterminisme moléculaire de cette voie de biosynthèse est encore mal connu mais il a néanmoins été démontré depuis les années 1960 que les enzymes catalysant les différentes étapes de la voie la synthèse des furocoumarines appartenaient à différentes familles. Les travaux présentés dans ce document se sont focalisés sur deux familles d'enzymes : les dioxygenases oxoglutarate dépendantes et les cytochromes P450s. La première étape de la voie de biosynthèse des furocoumarines consiste en une ortho-hydroxylation du p-coumarate qui mène à la formation de l'umbelliférone. Basé sur des travaux récents sur Arabidopsis, six gènes codants pour des dioxygénases ont été isolés chez Ruta graveolens, Citrus limetta et Pastinaca sativa. Les protéines correspondantes présentent plus de 58% d'identité avec la Féruloyle 6' Hydroxylase (F6'H) d'A. thaliana. La caractérisation fonctionnelle de ces enzymes a été réalisée dans un système d'expression hétérologue procaryote. Sur les 6 enzymes, trois n'ont pu être exprimée efficacement, et deux présentent une activité F6'H similaire à celle décrite pour A. thaliana. La dernière enzyme dispose de caractéristiques nouvelles non décrites à ce jour. Elle est en mesure de réaliser l'hydroxylation du féruloyle coA et du p-coumaroyle coA. Ces études in vitro ont été complétées par une exploration des fonctions de la protéine dans la plante. Une analyse fine du profil d'expression du gène a permis de mettre en évidence une expression qui est en corrélation avec le niveau de production d'umbelliférone. La fonction de la protéine a également été validée par une analyse des produits formés dans des feuilles de Nicotiana benthamiana transformées transitoirement. Les cytochromes P450 catalysent 60% des réactions de la voie de biosynthèse de furocoumarines. Un travail de criblage fonctionnel de cytochromes P450 identifiés au préalable chez Ammi majus et Thapsia garganica a été entrepris. Les analyses de bio-informatiques et les modifications apportées au niveau du mode opératoire pour l'expression dans la levure ont permis d'émettre des hypothèses concernant le rôle de certains P450 candidats. Ces travaux exploratoires et préliminaires font supposer de nouvelles conjectures relatives à cette voie de biosynthèseFuranocoumarins are secondary metabolites deriving from the phenylpropanoid biosynthetic pathway. These phytoalexins are especially involved in plant defense mechanisms against insects or phytopatogenous fungi and bacteria. The molecular control of this biosynthetic pathway is still poorly understood even though it has been demonstrated since the 1960s that enzymes catalyzing the different steps are belonging to different enzymatic families. The work presented here is focused on two enzyme families: oxoglutarate dependent dioxygenases and cytochrome P450s. The first step in the furanocoumarins biosynthetic pathway is the ortho-hydroxylation of p-coumarate, which leads to the formation of umbelliferone. Based on a recent work done on Arabidopsis, we isolated six genes encoding dioxygenases from Ruta graveolens, Citrus limetta and Pastinaca sativa. The corresponding proteins share more than 58% identity with the A. thaliana féruloyle 6' Hydroxylase (F6'H). The functional characterization of these enzymes was performed in a prokaryotic heterologous expression system. Of the six enzymes, three could not be functionnaly expressed and two exhibited a similar F6'H activity as described for A. thaliana. The last enzyme has new properties not described to date. It is able to achieve both hydroxylation of féruloyle CoA and p-coumaroyle CoA. These in vitro studies were completed by a functional exploration of the protein in planta. A detailed analysis of the gene expression pattern highlighted a link with the level of umbelliferone synthesis. The function of the protein was also confirmed by an analysis of the products formed in transiently transformed Nicotiana benthamiana leaves. Cytochrome P450s catalyze 60% of the reactions of the furanocoumarin biosynthetic pathway. Therefore, a functional screening of cytochrome P450 previously identified in Ammi majus and Thapsia garganica was undertaken. The bioinformatic analyses and the changes undertaken in the procedure for expression in yeast allowed drawing hypotheses on the function of some of these P450 candidates. These exploratory and preliminary experiments allowed suggesting new hypotheses about the biosynthetic pathway
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Savarin, Julie. "Caractérisation de la voie TCTP (TRANSLATIONALLY CONTROLLED TUMOR PROTEIN) chez Arabidopsis thaliana : identification des régulateurs de son accumulation et importance de la voie au cours du développement embryonnaire". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEN001.
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TCTP (Translationally Controlled Tumor Protein) est une protéine très conservée chez l'ensemble des eucaryotes. C’est une protéine vitale impliquée dans divers processus essentiels, et pour de nombreux organismes son absence conduit à la létalité dès les stades embryonnaires.Chez les animaux comme chez les végétaux, TCTP joue un rôle primordial dans la croissance et le développement des individus. En plus de son implication dans l’apoptose et la réparation de l’ADN, TCTP favorise la prolifération cellulaire, et se trouve donc être un élément important de la tumorigenèse. Chez les végétaux, la forte conservation de TCTP a permis la préservation de la plupart des fonctions décrites chez les animaux, mais les facteurs qui interviennent en amont ne sont pas encore connus.Par la mise en place, la conduite et la finalisation de deux cribles génétiques utilisant la plante modèle Arabidopsis thaliana, ce travail de thèse a cherché à identifier des facteurs situés en amont de TCTP. En parallèle, une seconde étude fut menée afin de mesurer l'impact de l'absence de TCTP sur les voies de l’auxine et des cytokinines au cours du développement embryonnaire, permettant de mieux comprendre l’origine de l’embryolétalité du mutant tctpTCTP (Translationally Controlled Tumor Protein) is strongly conserved among eukaryotes. It is a vital protein implicated in various major processes, and its absence leads to early embryolethality in many organisms. In plants as in animals, TCTP is a key factor of growth and development. Implicated in apoptosis and DNA repair, TCTP is also an enhancer of cell proliferation, and is a key element of tumorigenesis. Major functions of TCTP are conserved between plants and animals, but upstream factors are not known yet. Using a genetic screen on the model plant Arabidopsis thaliana, the principal goal of this thesis was to discover regulators of TCTP.In parallel, the impact of TCTP knockout on auxin and cytokinin pathways during embryo development was investigated
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Abdouni, Abdejabbarl. "Ouverture et croissance économique dans les pays en voie de développement : Contribution théorique et identification des liens empiriques à l'aide de l'économétrie des données de panel". Aix-Marseille 2, 2003. http://www.theses.fr/2003AIX24013.
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Chaveroux, Cédric. "Identification d'une nouvelle voie de signalisation impliquée dans la régulation des gènes par les acides aminés, chez les mammifères". Phd thesis, Université d'Auvergne - Clermont-Ferrand I, 2009. http://tel.archives-ouvertes.fr/tel-00726314.
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Chez les mammifères, l'environnement est un puissant régulateur de l'expression des gènes. Par exemple, en fonction de l'alimentation, la disponibilité en nutriments, en particulier en acides aminés, est responsable de l'induction de l'expression d'un certain nombre de gènes. Ainsi, des mécanismes moléculaires sont mis en jeu de façon à permettre la détection de ces variations et d'y répondre de façon appropriée. Lorsque l'un des neuf acides aminés essentiels vient à manquer, on observe une augmentation de la transcription de certains gènes. Cette activation de la transcription requière d'une part l'accumulation du facteur de transcription ATF4 et d'autre part la phosphorylation du facteur de transcription ATF2. La voie ATF4 a été identifiée et relativement bien décrite. En revanche les éléments régulateurs de la voie de signalisation en amonts du facteur ATF2 restent inconnus. Le but de ma thèse était donc de déterminer les différents intermédiaires responsables de la phosphorylation d'ATF2 en réponse à une carence en acides aminés. J'ai ainsi montré qu'une carence en acides aminés provoque la mise en jeu d'un module MAPK composé de MEKK1>MKK7>JNK2 contrôlant la phosphorylation d'ATF2 sur les résidus thréonine 69 et 71. J'ai montré que ce module est régulé en amont par deux GTPases Cdc42+Rac1 et par la protéine Gα12. Enfin, j'ai démontré l'impact de cette nouvelle voie de signalisation sur la transcription AARE-dépendante du gène ATF3 en réponse à une carence en acides aminés.
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Melis, Nicolas. "Identification de deux nouvelles cibles dans la gestion du stress oxydatif ; la protéine CFTR et la voie d’activation d’eIF5A". Thesis, Nice, 2015. http://www.theses.fr/2015NICE4030.
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Le stress oxydatif définit un phénomène cellulaire particulier caractérisé par un niveau élevé de molécules hautement réactives, essentiellement lié à l’utilisation de l’oxygène par les systèmes biologiques via la respiration. La dérégulation de l’état oxydatif de la cellule est à l’origine soit de processus d’adaptations efficaces (adaptation à l’altitude) soit de pathologies (AVC, infarctus). Ce travail de thèse s’est porté sur l’étude de deux nouvelles cibles pouvant induire une résistance/tolérance à la variation du stress oxydatif : la première est la protéine canal CFTR («Cystic Fibrosis Transmembrane conductance Regulator») et la seconde la voie d’activation d’eIF5A («eukaryotic Initiation translation Factor 5A»). Nous avons pu mettre en évidence que la protéine CFTR grâce à sa perméabilité au glutathion (l’antioxydant majoritaire cellulaire) est un modulateur de l’état oxydatif de la cellule, que ce soit lors de l’exposition à des agents cytotoxiques (cisplatine) ou lors de l’adaptation à des conditions hypoxiques chroniques. La deuxième cible identifiée est le facteur eIF5A qui est la seule protéine activée par la fixation d’un résidu hypusine. L’inhibition de cette modification post-traductionnelle protège les cellules d’une production d’espèces réactives induite par l’anoxie. Cette résistance à l’anoxie est accompagnée d’un profond remodelage métabolique et mitochondrial. Sur des modèles animaux d’ischémie (rein et cerveau), l’inhibition de l’activation d’eIF5A conduit à une protection des organes face à un manque d’oxygène. Ces études fondamentales ont des applications cliniques potentielles dans des pathologies humaines (infarctus, AVC, transplantation)Oxidative stress represents a particular cellular condition, characterized by an intracellular increase in thereactive species level. These species are highly reactive towards biomolecules and result of oxygenconsumption by biological systems essentially through respiration. Deregulation of the cellular oxidativestate can initiate adaptive processes (as elevation adaptation) or several human pathologies (stroke,infarct). This thesis work has been devoted to the study of two news potential targets allowing atolerance/resistance towards disequilibrium of oxidative stress; the first one is CFTR, a channel protein(«Cystic Fibrosis Transmembrane conductance Regulator»), and the second one is the activation pathwayof the translation factor eIF5A («eukaryotic Initiation translation Factor 5A»). Based on the peculiaractivity of CFTR, consisting in the transport of glutathione, the major antioxidant of the cell, weevidenced the role of CFTR in the management of cellular oxidative state during cytotoxic drugexposure (cisplatin) or during adaptation to chronical hypoxia. The second target, eIF5A is the only oneprotein described as post-translationally modified by fixation of a hypusine residue. We demonstratedthat inhibition of eiF5A activation protect cells from reactive oxygen species generated during anoxia. Atcellular level, this protection is accompanied with deep metabolic and mitochondrial changes. Usinganimal models, we showed that inhibition of this eiF5A activation allows a tolerance against ischemicaccident in different organs (kidney and brain). These fundamentals results can have extensiveapplication in human clinical use (infarct, stroke, graft)
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Champion, Antony. "Contrôle de la division cellulaire chez les plantes : identification d'une voie de signalisation de type SIN (Septum Initiation Network)". Paris 11, 2003. http://www.theses.fr/2003PA112035.
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Chez les Eucaryotes, la progression dans le cycle cellulaire est étroitement contrôlée par des complexes mitotiques CDK/cycline. Les études menées chez S. Cerevisiae et S. Pombe démontrent l'existence d'une cascade de signalisation additionnelle, dont la fonction consiste à mettre en place la cytokinèse, en lien avec la sortie de mitose. Chez S. Pombe, cette voie de signalisation est nommée "Septum Initiation Network" (SIN). Par analogie avec la levure, nous avons identifie et analysé le rôle d'éléments d'une voie de signalisation végétale de type SIN. Nous avons mis en évidence chez A. Thaliana et B. Napus des protéines similaires à la protéine G monomérique spg1p (AtSGP1, AtSGP2), à la kinase cdc7p (AtMAP3Ke1, AtMAP3Ke2, BnMAP3Kel), et à la kinase sid1p (AtMAP4K α1, AtMAP4Kα2, BnMAP4Kα2) de S. Pombe. Ces protéines végétales sont les premières de cette nature à avoir été caractérisées chez un Eucaryote pluricellulaire. Elles pourraient participer à un module de signalisation conservé au cours de l'évolution chez les champignons et les plantes. Nous avons démontré l'existence d'interactions physiques et fonctionnelles entre ces éléments végétaux de type SIN et ceux de S. Pombe. Les protéines AtSGP1/2, BnMAP3Ke1 et BnMAP4Kα2 complémentent respectivement les mutants spg1-B8, cdc7-24 et sid1-239 de S. Pombe. De plus, nous avons montré que la surexpression des protéines végétales chez S. Pombe induit des anomalies de cytokinèse. Une analyse des interactions physiques entre les éléments végétaux et ceux de S. Pombe a permis de compléter et de confirmer l'existence d'une voie de signalisation végétale de type SIN. Toutefois, la complémentation partielle des mutants de levure suggère que les protéines homologues de plantes et de S. Pombe ont divergé au cours de l'évolution. En parallèle, nous avons étudié la localisation intracellulaire des composants de cette cascade de signalisation. Nos observations révèlent une co-localisation des éléments dans le nucléole, suggérant un mécanisme original de régulation de cette voie de signalisation. L'ensemble de ces données, ainsi que le profil d'expression des gènes végétaux et l'analyse du phénotype de plantes antisens pour le gène AtMAP3Ke1 nous ont conduits à proposer l'existence d'une voie de signalisation végétale de type SIN contrôlant la division cellulaire chez les plantesThe time course of events shared by Eucaryotes all along the cell cycle, is strictly controlled by mitotic complexes involving the CDK/cyclin proteins. Studies carried out on S. Cerevisiae and S. Pombe enlight the involvement of an additional signalling cascade, the function of which consists in keeping the cytokinesis in concordance with the end of the mitosis. In S. Pombe, the signalling pathway is named SIN for Septum Initiation Network. Led by the analogy shared with yeast, we identified and analyzed the role of many items of the corresponding plant pathway. We identified A. Thaliana and B. Napus homologues of the fission yeast G protein spg1p (AtSGP1, AtSGP2), the kinase cdc7p (AtMAP3Ke1, AtMAP3Ke2, BnMAP3Ke1) and the kinase sid1p (AtMAP4Kα1, AtMAP4Kα2, BnMAP4Kα2). These are the first characterized homologues of a multicellular Eucaryote. Thcy might participate in a signalling module conserved along the evolution between fungi and plants. We demonstrated the existence of physical and functional interactions between both the plant and the s. Pombe SIN elements. AtSGP1/2, BnMAP3Ke1 and BnMAP4Kα2 are capable of complementing the spg1-B8, cdc7-24 and sid1-239 S. Pombe mutants respectively. Furthermore, we displayed anomalies in the cytokinesis process of wild type S. Pombe over-expressing the SIN-related proteins. An analysis of physical interplays between plant elements and those of the fission yeast clearly evidenced and confirmed the existence of a plant SlN-related signalling pathway. Partial complementation of the yeast mutants indicated that plant homologous proteins diverged from their yeast counterparts to some extend. In addition, we showed that the components colocalized within the nucleolus, which suggests a yet unnoticed regulating mechanisms of this pathway. These data, added to the expression patterns of the corresponding plant genes, and to the phenotypes of AtMAP3Ke1 antisense plants, led us to propose the consistent picture of a SIN related signalling pathway, which controls plant cell division
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Addis, Vanessa. "Identification de protéines impliquées dans le tri aux endosomes multivésiculaires : Une voie utilisée dans le bourgeonnement du VIH-1". Université Louis Pasteur (Strasbourg) (1971-2008), 2008. http://www.theses.fr/2008STR13081.
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L’endosome tardif ou MVB (MultiVesicular Body) est une station de tri protéique majeure dans les voies du trafic intracellulaire. La formation et le tri au MVB sont deux mécanismes liés qui font intervenir les Epsines, plusieurs complexes protéiques, appelés ESCRTs (Endosomal Sorting Complex Required for Transport), ainsi que les phosphoinositides membranaires (PtdIns) PtdIns(3)P et PtdIns(3,5)P2. Les Epsines sont des protéines caractérisées par un domaine ENTH (Epsin N-terminal homology) en N-terminal, qui est un module de liaison à des phosphoinositides membranaires. Notre laboratoire a montré que Ent3 et Ent5, deux Epsines de levure Saccharomyces cerevisiae, sont des effecteurs spécifiques du PtdIns(3,5)P2 aux endosomes. Elles sont nécessaires au tri des protéines membranaires au MVB et interagissent avec Vps27/Hrs de ESCRT-0 dans différents complexes de 500 kDa. Pour identifier les autres protéines appartenant à ces complexes, Ent3 et Ent5 ont été utilisées en tant qu’appât dans un crible protéomique de puces à protéines, détectant les interactants directs. Parmi eux, nous avons trouvé une protéine non caractérisée de 70 kDa, que nous avons nommé Vps76. Les levures vps76Δ possèdent un défaut spécifique de tri au MVB des cargos ubiquitinés et PtdIns(3,5)P2-dépendant. Nous proposons que Vps76 est essentielle au tri protéique au MVB et qu’elle agit comme un senseur de la machinerie de tri au MVB chez la levureLate endosome or multivesicular body (MVB) is the major sorting station of the intracellular membrane trafficking pathway. MVB formation and sorting are two linked mechanisms which require Epsins, different protein complexes called ESCRTs (Endosomal Sorting Complex Required for Transport) and of membrane lipid phosphoinositides (PtdIns) PtdIns(3)P and PtdIns(3,5)P2. Epsins are proteins characterized by an ENTH domain (Epsin N-terminal homology) that is a membrane phosphoinositide-binding module. Our laboratory showed that two yeast Saccharomyces cerevisiae Epsins, Ent3 and Ent5, are specific PtdIns(3,5)P2 effectors at the endosome. They are required for proteins sorting at the MVB and interact with the Vps27/Hrs ESCRT-0 into different proteins complexes around 500 kDa. To determine additional proteins that are present in these complexes, Ent3 and Ent5 were used as baits in a poteome protoarray screen, determining their direct interactors. Among these many, we found an uncharacterized 70 kDa protein, we named Vps76. The vps76Δ cells display a specific MVB sorting defect of ubiquitinated- and PtdIns(3,5)P2-dependent cargos. We propose Vps76 is required for MVB sorting and is acting as a “sensor” of the multivesicular body sorting machinery in yeast
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Baumgartner, Karin. "Public voices political discourse in the writings of Caroline de la Motte Fouqué". Oxford Bern Berlin Bruxelles Frankfurt, M. New York, NY Wien Lang, 2009. http://d-nb.info/991380282/04.
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