Development of physics-based models and design optimization of power electronic conversion systems

The main objective for physics based modeling of the power converter components is to design the whole converter with respect to physical and operational constraints. Therefore, all the elements and components of the energy conversion system are modeled numerically and combined together to achieve the whole system behavioral model. Previously proposed high frequency (HF) models of power converters are based on circuit models that are only related to the parasitic inner parameters of the power devices and the connections between the components. This dissertation aims to obtain appropriate physics-based models for power conversion systems, which not only can represent the steady state behavior of the components, but also can predict their high frequency characteristics. The developed physics-based model would represent the physical device with a high level of accuracy in predicting its operating condition. The proposed physics-based model enables us to accurately develop components such as; effective EMI filters, switching algorithms and circuit topologies [7]. One of the applications of the developed modeling technique is design of new sets of topologies for high-frequency, high efficiency converters for variable speed drives. The main advantage of the modeling method, presented in this dissertation, is the practical design of an inverter for high power applications with the ability to overcome the blocking voltage limitations of available power semiconductor devices. Another advantage is selection of the best matching topology with inherent reduction of switching losses which can be utilized to improve the overall efficiency. The physics-based modeling approach, in this dissertation, makes it possible to design any power electronic conversion system to meet electromagnetic standards and design constraints. This includes physical characteristics such as; decreasing the size and weight of the package, optimized interactions with the neighboring components and higher power density. In addition, the electromagnetic behaviors and signatures can be evaluated including the study of conducted and radiated EMI interactions in addition to the design of attenuation measures and enclosures.

Enhanced skip -list search algorithm in 3-layer mediator framework

The Three-Layer distributed mediation architecture, designed by Secure System Architecture laboratory, employed a layered framework of presence, integration, and homogenization mediators. The architecture does not have any central component that may affect the system reliability. A distributed search technique was adapted in the system to increase its reliability. An Enhanced Chord-like algorithm (E-Chord) was designed and deployed in the integration layer. The E-Chord is a skip-list algorithm based on Distributed Hash Table (DHT) which is a distributed but structured architecture. DHT is distributed in the sense that no central unit is required to maintain indexes, and it is structured in the sense that indexes are distributed over the nodes in a systematic manner. Each node maintains three kind of routing information: a frequency list, a successor/predecessor list, and a finger table. None of the nodes in the system maintains all indexes, and each node knows about some other nodes in the system. These nodes, also called composer mediators, were connected in a P2P fashion. ^ A special composer mediator called a global mediator initiates the keyword-based matching decomposition of the request using the E-Chord. It generates an Integrated Data Structure Graph (IDSG) on the fly, creates association and dependency relations between nodes in the IDSG, and then generates a Global IDSG (GIDSG). The GIDSG graph is a plan which guides the global mediator how to integrate data. It is also used to stream data from the mediators in the homogenization layer which connected to the data sources. The connectors start sending the data to the global mediator just after the global mediator creates the GIDSG and just before the global mediator sends the answer to the presence mediator. Using the E-Chord and GIDSG made the mediation system more scalable than using a central global schema repository since all the composers in the integration layer are capable of handling and routing requests. Also, when a composer fails, it would only minimally affect the entire mediation system. ^

Advanced Placement and American education: A Foucauldian analysis of the Advanced Placement Program of the college board

Advanced Placement is a series of courses and tests designed to determine mastery over introductory college material. It has become part of the American educational system. The changing conception of AP was examined using critical theory to determine what led to a view of continual success. The study utilized David Armstrong's variation of Michel Foucault's critical theory to construct an analytical framework. Black and Ubbes' data gathering techniques and Braun and Clark's data analysis were utilized as the analytical framework. Data included 1135 documents: 641 journal articles, 421 newspaper articles and 82 government documents. ^ The study revealed three historical ruptures correlated to three themes containing subthemes. The first rupture was the Sputnik launch in 1958. Its correlated theme was AP leading to school reform with subthemes of AP as reform for able students and AP's gaining of acceptance from secondary schools and higher education. The second rupture was the Nation at Risk report published in 1983. Its correlated theme was AP's shift in emphasis from the exam to the course with the subthemes of AP as a course, a shift in AP's target population, using AP courses to promote equity, and AP courses modifying curricula. The passage of the No Child Left Behind Act of 2001 was the third rupture. Its correlated theme was AP as a means to narrow the achievement gap with the subthemes of AP as a college preparatory program and the shifting of AP to an open access program. ^ The themes revealed a perception that progressively integrated the program into American education. The AP program changed emphasis from tests to curriculum, and is seen as the nation's premier academic program to promote reform and prepare students for college. It has become a major source of income for the College Board. In effect, AP has become an agent of privatization, spurring other private entities into competition for government funding. The change and growth of the program over the past 57 years resulted in a deep integration into American education. As such the program remains an intrinsic part of the system and continues to evolve within American education. ^

The effectiveness of an intelligent tutoring system on the attitude and achievement of developmental mathematics students in a community college

This study examined the effectiveness of intelligent tutoring system instruction, grounded in John Anderson's ACT theory of cognition, on the achievement and attitude of developmental mathematics students in the community college setting. The quasi-experimental research used a pretest-posttest control group design. The dependent variables were problem solving achievement, overall achievement, and attitude towards mathematics. The independent variable was instructional method. Four intact classes and two instructors participated in the study for one semester. Two classes (n = 35) served as experimental groups; they received six lessons with real-world problems using intelligent tutoring system instruction. The other two classes (n = 24) served as control groups; they received six lessons with real-world problems using traditional instruction including graphing calculator support. It was hypothesized that students taught problem solving using the intelligent tutoring system would achieve more on the dependent variables than students taught without the intelligent tutoring system. Posttest mean scores for one teacher produced a significant difference in overall achievement for the experimental group. The same teacher had higher means, not significantly, for the experimental group in problem solving achievement. The study did not indicate a significant difference in attitude mean scores. It was concluded that using an intelligent tutoring system in problem solving instruction may impact student's overall mathematics achievement and problem solving achievement. Other factors must be considered, such as the teacher's classroom experience, the teacher's experience with the intelligent tutoring system, trained technical support, and trained student support; as well as student learning styles, motivation, and overall mathematics ability.

Vulnerabilidade socioambiental no município de Natal, RN

Contemporary society lives surrounded by various types of risks, causing individuals to be taken by a constant feeling of fear and insecurity, as the negative risks, always bring some harm to the population directly or indirectly involved. The city of Natal has several risk areas, especially on the outskirts of the city, due to the occupation of spaces that have laws and / or natural physical limitations as well as the lack of urban organization, thus increasing the vulnerability of the population living in these areas. The principal objective of this research was to map the areas of social vulnerability and natural hazards in Natal, taking into account the interrelationships between social vulnerability and differential exposure to natural hazards. Therefore, it was necessary to establish, according to the methodology used, the degree of social vulnerability and vulnerability to natural hazard in which individuals are subject, to establish the relationship between society/ risks. In this case, the methodology proposed by Crepani (2001) which is based on ecodynamic Tricart (1977), which classifies the areas of risk and the degree of vulnerability of these areas according to the morphodynamic processes for preparation of the Vulnerability Index was used Physical natural, and for organizing the social Vulnerability Index adopted an adaptation of the Paulista social Vulnerability Index, prepared by SEADE (Fundação Sistema Estadual de Análise de Dados) of the State of São Paulo, drawing on data that denote social disadvantage at the census tract level. Then, with the superposition of these two indices, it was elaborated a Socioenvironmental Vulnerability Index. Thus, it is concluded that besides spatialize areas of risk which indicates the degree of vulnerability of individuals potentially exposed to natural hazard.

Gestão do sistema de produção e práticas enxutas adotadas nas indústrias paraibanas: um estudo multicaso

The evolution of the practices and strategies of manufacturing management, over the years, has made many companies realign their production systems in order to raise their competitiveness and operational performance. However, in most cases these changes are made in a heterogeneous manner, which ends up leaving the production system without a defined goal, which may end up damaging the managerial strategies of the organization as a whole. Thus, some organizations seek to use techniques and/or successful production practices used by other companies, believing can be able to reproduce the same results. An efficient production system must be fully planned and appropriate to the strategic objectives of the organization. Thus, this paper aims to identify the manufacturing management strategies adopted in paraibanas industries, as well as identify the lean practices used by them. Thus, a qualitative study was conducted, using as methodological basis the multicase study. Were made: direct observations, semi-structured interviews and questionnaires applied to those responsible by the production sector of the participating companies. As a result, it was possible to identify the type of manufacturing management system adopted by companies. Where it was detected that Company A uses a system of Modern Mass Production with focus on productivity and low cost and the Company B is using Lean Manufacturing system focused on quality and diversity. In the two organizations was possible to realize the application of lean practices where the Company what does not use the LM, possessed lean practices in standard extremely mature of utilization.

Proposta de modelo de gestão de riscos para uma IFES visando a realização de auditoria baseada em riscos

Organizations are susceptible to the occurrence of many events that may affect the achievement of their objectives. As a result, Brazilian Public Administration supervisory bodies have required institutions to adopt risk management policies. Given the large number of recommendations issued by Federal Audit Court (TCU) to various Federal Institutions of Higher Education (IFES) in this area, it is proposed a risk management model for Universidade Federal do Rio Grande do Norte (UFRN). This is an applied, exploratory and qualitative study. Regarding to technical procedures, it is characterized as documentary analysis, bibliographical research, case study and action research. The bibliographical research was used to support the elaboration of the Risk Management Guide for Federal Institutions of Higher Education (GERIFES). The documentary analysis, in turn, was used with the aim of knowing the organizational structure and the university´s macroprocesses. The author works in the university internal auditing department and shares the same problem. This characterizes the work as an action research. The case study supported both the elaboration of the guide and the simulation of the specific functionality for the university information system, demonstrated through the User Manual Module "Risk Management" proposed for the Integrated System of Property, Administration and Contracts (SIPAC). This manual has been prepared in order to facilitate the use of this tool if it will be incorporated into the university information system. As research results, a risk management model for UFRN was elaborated and a simulation of an informational tool, which is able to manage risks related to events that may affect the achievement of institutional objectives, was provided to the university administration.

Influência da pressão e da vazão de concentrado sobre o desempenho de ultrafiltração no pós-tratamento de esgotos

Despite the numerous advantages resulting from the use of membrane filters technology, intrinsic limitations fouling process become relevant to its applicability. The control of operating conditions is an important tool to mitigate fouling and achieve good levels of efficiency. In this sense, the objective of this study was to investigate the effect of transmembrane pressure and concentrate flow in the performance of ultrafiltration, applied to the post-treatment of domestic sewage. The process was evaluated and optimized by varying the pressure (0.5 and 1.5 bar) and the concentrate flow (300 and 600 L/h), using a 22 factorial design, in order to investigate the effects on the permeate flow and quality of effluents generated at each operating condition. We evaluated the following quality indicators for permeate: pH, electrical conductivity, total suspended solids, turbidity, calcium and Chemical Oxygen Demand (COD). In all tests, we observed marked reduction in the permeate flux at the early stages, followed by a slow decline that lasted until it reaches a relatively constant level, around 120 minutes of filtration. The increased pressure resulted in a higher initial permeate flux, but the decrease of the flow with time is greater for tests at higher pressure, indicating a more pronounced fouling process. On the other hand, increasing the concentrate flow resulted in a slower decline in permeate flux with the filtration time. Regarding the quality of permeate, the transmembrane pressure of 0,5 bar was the one that allowed better results, and was statistically confirmed through the two-way ANOVA test with repeated measures, significant effect of pressure on the turbidity of the permeate. The concentrate flow, in turn, showed no significant influence on any of the quality parameters. Thus, we conclude that, from an economic and environmental point of view, it is more interesting to operate ultrafiltration membrane system with a lower concentrate flow associated with a low transmembrane pressure, since under these conditions will produce less waste, and the permeate will present lower concentrations of the analyzed constituent, especially lower turbidity.

Capacidades estatais para implementação de políticas públicas em ambientes federativos: o caso do Programa Bolsa Família

This thesis aims to understand the extent to which state capacities of state governments explain the effectiveness of the implementation of Programa Bolsa Família (PBF) in the Northeast, adopting the implementation of the theory as the main theoretical lens and more specifically the concept of state capacity. Methodologically is a study of public policy evaluation, and categorized as a process of evaluation study or implementation. Given the specificity of the object is classified as a multi case study research covering the states of Sergipe, Rio Grande do Norte and Bahia. In addition to using secondary data, the study used semi-structured interviews with members of Intersectoral Committees responsible for the actions of PBF and the Cadastro Único at the state level, composed of representatives of the areas of the state government of Social Welfare, Education and Health. the main findings related to technical and administrative capacities and policies were found: infrastructure with weakness in human resources, technological and financial resources; intra-governmental coordination with boundaries between PBF and Unified Social Assistance System , and the actions of conditionality of health and Health Unic System Basic Attention; intergovernmental coordination carried out mostly by the distance limitations of displacement and incipient regional decentralization of actions; based monitoring in the municipalities of lower performance and from the parameters placed by the federal government and political capacities; representative political system is hardly accessed by instances of program management; minor social participation and low articulation with related issues advice to PBF; audit control by any outside agencies. The thesis concludes that depending on the capabilities found implementing weaknesses are not unique to the program's actions, but from the very institutional capacity of the systems in which it operates that are the Unified Social Assistance System, the Health Unic System and the Educational System. In other words limitations of their own state capacities of the state governments and the municipal governments of each territory, such as quantitative insufficiency and qualification of human resources, financial and institutional resources, lack instance promoting decentralization (Intergovernmental and intra-governmental) as well the weakness or absence of a network of local social services are also factors that explain the program management performance and state capabilities of arrangements formed by states and municipalities in the PBF, only to partially deal with the complexity of joints involving Implementation of the program with regard to inter and intra-governmental action.

Capacidades estatais para implementação de políticas públicas em ambientes federativos: o caso do Programa Bolsa Família

This thesis aims to understand the extent to which state capacities of state governments explain the effectiveness of the implementation of Programa Bolsa Família (PBF) in the Northeast, adopting the implementation of the theory as the main theoretical lens and more specifically the concept of state capacity. Methodologically is a study of public policy evaluation, and categorized as a process of evaluation study or implementation. Given the specificity of the object is classified as a multi case study research covering the states of Sergipe, Rio Grande do Norte and Bahia. In addition to using secondary data, the study used semi-structured interviews with members of Intersectoral Committees responsible for the actions of PBF and the Cadastro Único at the state level, composed of representatives of the areas of the state government of Social Welfare, Education and Health. the main findings related to technical and administrative capacities and policies were found: infrastructure with weakness in human resources, technological and financial resources; intra-governmental coordination with boundaries between PBF and Unified Social Assistance System , and the actions of conditionality of health and Health Unic System Basic Attention; intergovernmental coordination carried out mostly by the distance limitations of displacement and incipient regional decentralization of actions; based monitoring in the municipalities of lower performance and from the parameters placed by the federal government and political capacities; representative political system is hardly accessed by instances of program management; minor social participation and low articulation with related issues advice to PBF; audit control by any outside agencies. The thesis concludes that depending on the capabilities found implementing weaknesses are not unique to the program's actions, but from the very institutional capacity of the systems in which it operates that are the Unified Social Assistance System, the Health Unic System and the Educational System. In other words limitations of their own state capacities of the state governments and the municipal governments of each territory, such as quantitative insufficiency and qualification of human resources, financial and institutional resources, lack instance promoting decentralization (Intergovernmental and intra-governmental) as well the weakness or absence of a network of local social services are also factors that explain the program management performance and state capabilities of arrangements formed by states and municipalities in the PBF, only to partially deal with the complexity of joints involving Implementation of the program with regard to inter and intra-governmental action.

Práticas pedagógicas e inclusão escolar: o processo de ensino-aprendizagem de alunas com deficiência intelectual

This research aimed to know and analyze the pedagogical practices that have been developed in the teaching and learning of students with Intellectual Disability (DI), enrolled at common class of elementary school I. The study was conducted in a public school at Natal/RN, involving two students with DI, a multipurpose teacher, a teaching assistant, a teacher of arts and educational coordinator. As for methodological choice, we chose to develop a qualitative study, undertaking a case study. As tools for the construction of the data we use: semi-structured interviews, participant observation, field diary and document analysis. Data analysis reveals that the institution in which the research was undertaken gradually implementing changes in order to develop an inclusive practice, consistent with its assumptions. Regarding the practices developed in the teaching and learning of students with intellectual disabilities, it was possible to realize the fulfillment of certain adjustments in relation to the objectives, activities and some content, involving the use of resources and varied strategies. With regard to educational activities, we found that these had different levels of complexity, covering both basic goals as more complex objectives. From the observations, we realize that the Assistant Professor of mediations during varied activities as challenging tool in intellectual processes. We note, too, a dynamic classroom in which disabled students were under the guidance of Assistant Professor, and other students with all-round teacher who had a fairly traditional teaching methodology. It created thus an isolation situation, since there was no proposition practices to be developed with all students, and interaction among classmates, generally quite restricted. Although were highlighted developments in the social and academic learning of the surveyed students, the teachers said they did not feel prepared to work freight inclusion. The study reveals the need for teachers reviewing some actions undertaken, in order to develop more democratic pedagogical practices of education, stimulating the interactions between students, by proposing challenging activities that promote the formation and concepts. In addition, it points to the need of the education system invest and encourage the qualification of teachers with regard to education in an inclusive perspective, through actions that promote lifelong learning. It needs to be developed on the teacher a reflective attitude, resulting in a view that due diligence must be entered in practice inherent in teaching in order to use to enhance their educational experience.

Práticas pedagógicas e inclusão escolar: o processo de ensino-aprendizagem de alunas com deficiência intelectual

This research aimed to know and analyze the pedagogical practices that have been developed in the teaching and learning of students with Intellectual Disability (DI), enrolled at common class of elementary school I. The study was conducted in a public school at Natal/RN, involving two students with DI, a multipurpose teacher, a teaching assistant, a teacher of arts and educational coordinator. As for methodological choice, we chose to develop a qualitative study, undertaking a case study. As tools for the construction of the data we use: semi-structured interviews, participant observation, field diary and document analysis. Data analysis reveals that the institution in which the research was undertaken gradually implementing changes in order to develop an inclusive practice, consistent with its assumptions. Regarding the practices developed in the teaching and learning of students with intellectual disabilities, it was possible to realize the fulfillment of certain adjustments in relation to the objectives, activities and some content, involving the use of resources and varied strategies. With regard to educational activities, we found that these had different levels of complexity, covering both basic goals as more complex objectives. From the observations, we realize that the Assistant Professor of mediations during varied activities as challenging tool in intellectual processes. We note, too, a dynamic classroom in which disabled students were under the guidance of Assistant Professor, and other students with all-round teacher who had a fairly traditional teaching methodology. It created thus an isolation situation, since there was no proposition practices to be developed with all students, and interaction among classmates, generally quite restricted. Although were highlighted developments in the social and academic learning of the surveyed students, the teachers said they did not feel prepared to work freight inclusion. The study reveals the need for teachers reviewing some actions undertaken, in order to develop more democratic pedagogical practices of education, stimulating the interactions between students, by proposing challenging activities that promote the formation and concepts. In addition, it points to the need of the education system invest and encourage the qualification of teachers with regard to education in an inclusive perspective, through actions that promote lifelong learning. It needs to be developed on the teacher a reflective attitude, resulting in a view that due diligence must be entered in practice inherent in teaching in order to use to enhance their educational experience.

Progettazione e implementazione di una incarnazione biochimica per il simulatore Alchemist

Scopo di questo elaborato di tesi è la modellazione e l’implementazione di una estensione del simulatore Alchemist, denominata Biochemistry, che permetta di simulare un ambiente multi-cellulare. Al fine di simulare il maggior numero possibile di processi biologici, il simulatore dovrà consentire di modellare l’eterogeneità cellulare attraverso la modellazione di diversi aspetti dei sistemi cellulari, quali: reazioni intracellulari, segnalazione tra cellule adiacenti, giunzioni cellulari e movimento. Dovrà, inoltre, essere ammissibile anche l’esecuzione di azioni impossibili nel mondo reale, come la distruzione o la creazione dal nulla di molecole chimiche. In maniera più specifica si sono modellati ed implementati i seguenti processi biochimici: creazione e distruzione di molecole chimiche, reazioni biochimiche intracellulari, scambio di molecole tra cellule adiacenti, creazione e distruzione di giunzioni cellulari. È stata dunque posta particolare enfasi nella modellazione delle reazioni tra cellule vicine, il cui meccanismo è simile a quello usato nella segnalazione cellulare. Ogni parte del sistema è stata modellata seguendo fenomeni realmente presenti nei sistemi multi-cellulari, e documentati in letteratura. Per la specifica delle reazioni chimiche, date in ingresso alla simulazione, è stata necessaria l’implementazione di un Domain Specific Language (DSL) che consente la scrittura di reazioni in modo simile al linguaggio naturale, consentendo l’uso del simulatore anche a persone senza particolari conoscenze di biologia. La correttezza del progetto è stata validata tramite test compiuti con dati presenti in letteratura e inerenti a processi biologici noti e ampiamente studiati.

O uso da Divergência de Kullback-Leibler e da Divergência Generalizada como medida de similaridade em sistemas CBIR

The content-based image retrieval is important for various purposes like disease diagnoses from computerized tomography, for example. The relevance, social and economic of image retrieval systems has created the necessity of its improvement. Within this context, the content-based image retrieval systems are composed of two stages, the feature extraction and similarity measurement. The stage of similarity is still a challenge due to the wide variety of similarity measurement functions, which can be combined with the different techniques present in the recovery process and return results that aren’t always the most satisfactory. The most common functions used to measure the similarity are the Euclidean and Cosine, but some researchers have noted some limitations in these functions conventional proximity, in the step of search by similarity. For that reason, the Bregman divergences (Kullback Leibler and I-Generalized) have attracted the attention of researchers, due to its flexibility in the similarity analysis. Thus, the aim of this research was to conduct a comparative study over the use of Bregman divergences in relation the Euclidean and Cosine functions, in the step similarity of content-based image retrieval, checking the advantages and disadvantages of each function. For this, it was created a content-based image retrieval system in two stages: offline and online, using approaches BSM, FISM, BoVW and BoVW-SPM. With this system was created three groups of experiments using databases: Caltech101, Oxford and UK-bench. The performance of content-based image retrieval system using the different functions of similarity was tested through of evaluation measures: Mean Average Precision, normalized Discounted Cumulative Gain, precision at k, precision x recall. Finally, this study shows that the use of Bregman divergences (Kullback Leibler and Generalized) obtains better results than the Euclidean and Cosine measures with significant gains for content-based image retrieval.

Caractérisation de l’activité Nur77 et de ses complexes en essais BRET par complémentation

Dans le système nerveux central, la dopamine joue un rôle crucial dans de nombreuses fonctions physiologiques telles que : l’apprentissage, le mouvement volontaire, la motivation, la cognition et la production hormonale. Il a été aussi démontré que le système de signalisation dopaminergique est altéré dans plusieurs maladies neurologiques et psychiatriques comme la maladie de Parkinson et la schizophrénie. Des études, effectuées dans le laboratoire du Dr.Daniel Lévesque (laboratoire d’accueil), ont montré que les récepteurs nucléaires Nur77 (NR4A1, NGFI-B) et RXRγ (retinoid X receptors γ) sont impliqués dans la régulation des effets de la dopamine dans le système nerveux central. De plus, ces données suggèrent que le complexe Nur77 et RXR joueraient un rôle crucial dans l’effet des médicaments antipsychotiques et antiparkinsoniens. Toutefois, très peu de médicaments ciblant Nur77 ont été identifiés à ce jour et les médicaments agissant sur RXRγ restent mal caractérisés. En outre, les analyses actuellement disponibles ne peuvent pas résumer la complexité des activités des NRs et génèrent des mesures indirectes des activités des drogues. Afin de mieux comprendre comment est régulée l’interaction Nur77/RXRγ dans ces processus, mon projet a été de mettre au point un essai BRET (Bioluminescence Resonance Energy Transfer) et PCA-BRET (Protein Complementation Assay-BRET) basé sur le recrutement d'un motif mimant un co-activateur fusionné avec la YFP. Nos différents essais ont été validés par courbes dose-réponse en utilisant différents composés RXR . Les EC50 (concentration efficace médiane, qui permet de mesurer l'efficacité d'un composé) obtenues étaient très semblables aux valeurs précédemment rapportées dans la littérature. Nous avons aussi pu identifier un composé le SR11237 (BMS649) qui semble posséder une sélectivité pour le complexe Nur77/RXRγ par rapport aux complexes Nurr1/RXRγ et RXRγ /RXRγ. Nos résultats indiquent que ces essais de BRET peuvent être utilisés pour évaluer la sélectivité de nouveaux composés pour les complexes Nur77/RXRγ, Nurr1/RXRγ et RXRγ /RXRγ. Un autre aspect de mon projet de doctorat a été de mettre en évidence par BRET l’importance de la SUMOylation dans la régulation de l'activité de Nur77 dans sa forme monomèrique, homodimèrique et hétérodimèrique. Nous avons ainsi identifié que Nur77 recrute principalement SUMO2 sur sa lysine 577. Il est intéressant de noté que le recrutement de la SUMO2 à Nur77 est potentialisé en présence de la SUMO E3 Ligase PIASγ. Aussi, la perte de la SUMOylation sur la lysine 577 entraîne l'incapacité de Nur77 de recruter divers motifs de co-activation mais pas pour ses formes homo- et hétérodimèrique. Cependant, la présence de PIASγ ne potentialise pas le recrutement du co-activateur, suggérant que cette SUMO E3 Ligase est seulement impliqué dans le processus de recrutement de la SUMO mais pas dans celui du co-activateur. Nous avons ainsi déterminé une nouvelle modification post-traductionnelle sur Nur77 régulant spécifiquement son activité monomérique Ces projets pourraient donc apporter de nouvelles données cruciales pour l’amélioration du traitement de la maladie de Parkinson ou de la schizophrénie, ainsi que d'obtenir une meilleure compréhension sur les mécanismes permettant la régulation de la fonction de Nur77