62 research outputs found

    Functional characterization of alternative splice variants of the Drosophila GATA transcription factor serpent containing either one or two zinc finger domains

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    Les facteurs de transcription GATA jouent un rôle crucial dans divers processus de développement chez les animaux bilatéraux. Chez les mammifères, six facteurs GATA sont présents et ils jouent des rôles essentiels dans différents tissus tels que le sang, l'intestin, le foie et les gonades. Les protéines GATA possèdent deux domaines hautement conservés, les doigts de zinc N-terminal et C-terminal. Le doigt C-terminal reconnaît le motif consensus de liaison à l'ADN GATA, tandis que le doigt N-terminal stabilise la fixation aux séquences palindromiques d'ADN et permet leur interaction avec les cofacteurs de la famille Friend Of GATA (FOG). Les mutations des doigts de zinc GATA sont associées à un vaste éventail de maladies humaines dont la gravité dépend du gène GATA affecté et de la position de la mutation dans les doigts de zinc. De nombreuses études ont démontré le haut niveau de similarités moléculaires et fonctionnelles existant entre les mouches et les humains. La drosophile possède cinq facteurs GATA contenant un ou deux doigts de zinc, dont les séquences sont presque identiques à celles des doigts de zinc canoniques des vertébrés. Parmi eux, le facteur GATA de la drosophile Serpent (Srp) est requis pour la formation des cellules sanguines, de l'intestin et du corps gras ainsi que pendant l'ovogenèse. Dans tous ces tissus, deux isoformes de Srp sont générées par un événement d'épissage alternatif donnant naissance à des protéines contenant soit les deux doigts de zinc (N- et C-terminal, d'où le nom de cette isoforme : SrpNC) ou uniquement le doigt de zinc C-terminal (SrpC). Dans un travail précédent, notre équipe a montré que SrpC et SrpNC activent certains gènes cibles de manière similaire mais aussi elles en régulent d'autres différemment. En plus, l'interaction entre SrpNC et son cofacteur FOG, U-shaped, est responsable de certaines mais pas de toutes les activités distinctes de SrpC et SrpNC. Le but de cette étude est de fournir une investigation génétique approfondie des rôles fonctionnels différentiels possibles des isoformes Srp au cours du développement de la drosophile. En utilisant la technologie CRISPR/Cas9, nous avons généré deux lignées de mouches mutantes invalidées soit pour SrpC ou pour SrpNC. En outre, nous avons produit une troisième lignée de mouche mutante dans laquelle nous avons spécifiquement introduit dans le doigt de zinc N-terminal de Srp une mutation ponctuelle qui modifie son interaction avec U-shaped. L'analyse de ces mutants a révélé que les deux isoformes régulent d'une manière redondante la transcription d'un ensemble commun de gènes au cours du développement intestinal ainsi que de quelques gènes impliqués dans l'hématopoïèse précoce. Étonnamment, les mouches dépourvues de SrpNC (isoforme contenant deux doigts de zinc comme les facteurs GATA des mammifères) sont viables, montrant que cette isoforme est dispensable pour la plupart des processus de développement contrôlés par Srp. Néanmoins, SrpNC semble être spécifiquement nécessaire pour le maintien de l'homéostasie des cellules sanguines et pour la fertilité des mouches. En outre, la perturbation de l'interaction de Srp et de son cofacteur FOG U-shaped équivaut à la perte complète de l'isoforme SrpNC, montrant que SrpNC forme un complexe avec U-shaped pour assurer ses fonctions. En revanche, notre approche génétique a révélé que l'isoforme SrpC est essentielle pour la viabilité et le développement du corps gras, suggérant que cette isoforme régule différents programmes développementaux par rapport à SrpNC. Dans l'ensemble, nos résultats révèlent une plus grande flexibilité fonctionnelle jouée par les doigts de zinc GATA pour remplir leurs nombreux rôles tout au long du développement. En outre, ce travail illustre que, comme la duplication du génome chez les vertébrés, l'épissage alternatif fournit une stratégie efficace pour promouvoir la sous-fonctionnalisation et générer la diversité fonctionnelle des facteurs GATA chez les invertébrés.GATA transcription factors play crucial roles in various developmental processes throughout bilaterian animals. In mammals, six GATA factors are present and they play essential functions in different tissues such as the blood, the gut, the liver and the gonads. GATA proteins have two highly conserved domains, the N-terminal and the C-terminal zinc fingers. The C-terminal finger recognizes GATA DNA-binding consensus motif, while the N-terminal finger stabilizes fixation to DNA palindromic sequences and allows their interaction with cofactors of the Friend Of GATA (FOG) family. GATA zinc finger mutations are associated to a vast panel of human diseases whose severity depends on the affected GATA gene and on the position of the mutation in the zinc fingers. Numerous studies have demonstrated the high level of molecular and functional similarities existing between flies and humans. Drosophila melanogaster has five GATA factors containing either one or two zinc fingers, whose sequences are almost identical to those of the canonical zinc fingers of vertebrates. Among them, the Drosophila GATA factor Serpent (Srp) is required for the formation of blood cells, gut and fat body as well as during oogenesis. In all these tissues, two isoforms of Srp are generated through an alternative splicing event giving rise to proteins containing either both zinc fingers (N- and C-terminal, hence the name of this isoform: SrpNC) or only the C-terminal zinc finger (SrpC). In a previous work, our team has shown that SrpC and SrpNC activate some genes in a similar manner but also they regulate others differently. Moreover, interaction between SrpNC and its cofactor FOG, U-shaped, is responsible for some but not all aspects of the distinct activities of SrpC and SrpNC. The purpose of this study is to provide a deep genetic investigation of possible differential functional roles of Srp isoforms during Drosophila development. Using CRISPR/Cas9 technology, we generated two mutant fly lines deleted either of SrpC or of SrpNC. In addition, we produced a third mutant fly line in which we specifically introduced into the N-terminal zinc finger of Srp a single point mutation that alters its interaction with U-shaped. Analysis of these mutants revealed that both isoforms regulate redundantly the transcription of a common set of genes during gut development as well as few genes involved during early hematopoiesis. Surprisingly, flies devoid of SrpNC (isoform containing two-zinc fingers as the mammalian GATA factors) are viable, showing that this isoform is dispensable for most of the developmental processes controlled by Srp. Nonetheless, SrpNC appears to be specifically required in the maintenance of blood cell homeostasis and for fly fertility. Furthermore, disrupting the interaction of Srp and its FOG cofactor U-shaped is equivalent to the complete loss of the isoform SrpNC, showing that SrpNC forms a complex with U-shaped to ensure its functions. In contrast, our genetic approach unraveled that SrpC isoform is essential for viability and fat body development, suggesting that this isoform regulate different developmental programs compared to SrpNC. Altogether, our results reveal a greater functional flexibility played by the GATA zinc fingers to fulfil their many roles throughout development. Also, this work illustrates that, like genome duplication in vertebrates, alternative splicing provides an efficient strategy to promote subfunctionalization and generate GATA functional diversity in invertebrates

    Protein-Protein Docking with F2Dock 2.0 and GB-Rerank

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    Rezaul Chowdhury is with UT Austin; Muhibur Rasheed is with UT Austin; Maysam Moussalem is with UT Austin; Donald Keidel is with The Scripps Research Institute; Arthur Olson is with The Scripps Research Institute; Michel Sanner is with The Scripps Research Institute; Chandrajit Bajaj is with The Scripps Research Institute.Motivation -- Computational simulation of protein-protein docking can expedite the process of molecular modeling and drug discovery. This paper reports on our new F2 Dock protocol which improves the state of the art in initial stage rigid body exhaustive docking search, scoring and ranking by introducing improvements in the shape-complementarity and electrostatics affinity functions, a new knowledge-based interface propensity term with FFT formulation, a set of novel knowledge-based filters and finally a solvation energy (GBSA) based reranking technique. Our algorithms are based on highly efficient data structures including the dynamic packing grids and octrees which significantly speed up the computations and also provide guaranteed bounds on approximation error. Results -- The improved affinity functions show superior performance compared to their traditional counterparts in finding correct docking poses at higher ranks. We found that the new filters and the GBSA based reranking individually and in combination significantly improve the accuracy of docking predictions with only minor increase in computation time. We compared F2 Dock 2.0 with ZDock 3.0.2 and found improvements over it, specifically among 176 complexes in ZLab Benchmark 4.0, F2 Dock 2.0 finds a near-native solution as the top prediction for 22 complexes; where ZDock 3.0.2 does so for 13 complexes. F2 Dock 2.0 finds a near-native solution within the top 1000 predictions for 106 complexes as opposed to 104 complexes for ZDock 3.0.2. However, there are 17 and 15 complexes where F2 Dock 2.0 finds a solution but ZDock 3.0.2 does not and vice versa; which indicates that the two docking protocols can also complement each other. Availability -- The docking protocol has been implemented as a server with a graphical client (TexMol) which allows the user to manage multiple docking jobs, and visualize the docked poses and interfaces. Both the server and client are available for download. Server: http://www.cs.utexas.edu/~bajaj/cvc/soft​ware/f2dock.shtml. Client: http://www.cs.utexas.edu/~bajaj/cvc/soft​ware/f2dockclient.shtml.The research of C.B., R.C., M.M., and M.R. of University of Texas, was supported in part by National Science Foundation (NSF) grant CNS-0540033, and grants from the National Institutes of Health (NIH) R01-GM074258, R01-GM073087, R01-EB004873. The research of M.M. was additionally supported by an NSF Graduate Research Fellowship. The research of M.S. and A.O. of TSRI was supported in part by a subcontract on NIH grant R01-GM073087. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Computer Science

    Vertebral artery dissection: an important differential diagnosis of vertigo

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    Univ Fed Sao Paulo UNIFESP, Dept Otorrinolaringol & Cirurg Cabeca & Pescoco, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Otorrinolaringol & Cirurg Cabeca & Pescoco, Sao Paulo, SP, BrazilWeb of Scienc

    Vertebral artery dissection: an important differential diagnosis of vertigo

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    RELATO DE CASO: ATIVAÇÃO MACROFÁGICA (SAM) EM UM PACIENTE DE 14 ANOS

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     Síndrome de ativação macrofágica (SAM) é uma entidade associada com formas familiares e adquiridas. As formas adquiridas podem ser desencadeadas por infecções, neoplasias, imunodeficiências e doenças reumáticas. A SAM associada a AIJ é extremamente rara. A SAM associada a AIJ foi inicialmente descrita por Hadchouel et al. em 1985. Essa síndrome ocorre principalmente na forma sistêmica da AIJ. Pacientes com SAM apresentam febre alta prolongada, hepato e esplenomegalia, sangramentos, adenomegalia generalizada, exantemas, icterícia, podendo evoluir com insuficiência hepática aguda, coma, CIVD e falência de múltiplos órgãos. Anemia, leucopenia, plaquetopenia, hipofibrinogenemia e alargamentos dos tempos de coagulação ocorrem habitualmente em todos os pacientes. A presença de numerosos macrófagos na medula óssea, fagocitando células sangüíneas (hemofagocitose), sem evidência de malignidade, é característica da SAM. A doença pode ser desencadeada por agentes infecciosos virais como varicela-zoster, hepatite A, Epstein-Barr e coxsackie, terapia com ouro, ácido acetilsalicílico e outros antiinflamatórios não-hormonais, methotrexate, sulfasalazina e penicilamina. Para o tratamento da síndrome hemofagocítica, inicialmente deve-se suspender todos os antiinflamatórios não-hormonais e drogas de base.O corticóide é a droga de escolha em uso endovenoso, particularmente pulsoterapia com metilprednisolona. Atualmente, a segunda droga indicada na literatura é a Ciclosporina, particularmente nos pacientes não responsivos aos corticosteróides

    Terapia tópica de irrigação nasal de alto volume com solução de budesonida em rinossinusite crônica de difícil tratamento

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    Introduction: Chronic rhinosinusitis (CRS) is termed difficult-to-treat when patients do not reach acceptable level of control despite adequate surgery, intranasal corticosteroid treatment and up to 2 short courses of systemic antibiotics or corticosteroids in the preceding year. Recently, high-volume corticosteroid nasal irrigations have been recommended for CRS treatment. Objective: To assess high-volume budesonide nasal irrigations for difficult-to-treat CRS. Methods: Prospective uncontrolled intervention trial. Participants were assessed before- and 3 months after nasal irrigation with 1 mg of budesonide in 500 mL of saline solution daily for 2 days. Subjective (satisfactory clinical improvement) and objective (SNOT-22 questionnaire and Lund-Kennedy endoscopic scores) assessments were performed. Results: Sixteen patients were included, and 13 (81.3%) described satisfactory clinical improvement. SNOT-22 mean scores (50.2-29.6; p = 0.006) and Lund-Kennedy mean scores (8.8-5.1; p=0.01) improved significantly. Individually, 75% of patients improved SNOT-22 scores, and 75% improved Lund-Kennedy scores after high volume budesonide nasal irrigations. Conclusion: High-volume corticosteroid nasal irrigations are a good option in difficult-to-treat CRS control of disease, reaching 81.3% success control and significant improvement of SNOT-22 and Lund-Kennedy scores. (C) 2015 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda.Introdução: A rinossinusite crônica (RSC) de difícil tratamento é aquela inadequadamente controlada com cirurgia, corticosteroides tópicos em spray e até dois ciclos de medicação sistêmica em um ano. Atualmente, tem sido preconizado o uso de irrigações nasais de corticosteroides em alto volume para seu tratamento. Objetivo: Avaliar o uso da terapia tópica de irrigações nasais com budesonida em alto volume nos pacientes com RSC de difícil tratamento. Método: Estudo prospectivo de intervenção não controlado em RSC de difícil tratamento com 3 meses de terapia tópica de irrigação (1 mg de budesonida diluído em 500 mL de soro fisiológico para ser utilizado em dois dias). Realizada avaliação subjetiva (melhora clínica satisfatória) e objetiva (questionário SNOT-22 e classificação endoscópica de Lund-Kennedy). Resultados: Foram incluídos 16 pacientes, sendo que 13 (81,3%) consideraram sua melhora clínica satisfatória. Houve melhora significante das médias de SNOT-22 (50,2 a 29,6; p = 0,006) e de Lund-Kennedy (8,8 a 5,1; p = 0,01). Individualmente, 75% dos pacientes apresentaram melhora do SNOT-22 e 75%, do Lund-Kennedy. Conclusão: A terapia tópica de irrigação de alto volume de corticosteroide é uma boa opção no controle clínico dos pacientes com rinossinusite crônica de difícil tratamento, com controle adequado de 81,3% destes pacientes e melhora significante do SNOT-22 e do Lund-Kennedy. © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY- license (https://creativecommons. org/licenses/by/4.0/).Univ Fed Sao Paulo EPM UNIFESP, Escola Paulista Med, Dept Otorhinolaryngol & Head & Neck Surg, Sect Rhinol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo EPM UNIFESP, Escola Paulista Med, Dept Otorhinolaryngol & Head & Neck Surg, Sect Rhinol, Sao Paulo, SP, BrazilWeb of Scienc

    Novel therapeutic strategies for spinal osteosarcomas

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    At the dawn of the third millennium, cancer has become the bane of twenty-first century man, and remains a predominant public health burden, affecting welfare and life expectancy globally. Spinal osteogenic sarcoma, a primary spinal malignant tumor, is a rare and challenging neoplastic disease to treat. After the conventional therapeutic modalities of chemotherapy, radiation and surgery have been exhausted, there is currently no available alternative therapy in managing cases of spinal osteosarcoma. The defining signatures of tumor survival are characterised by cancer cell ability to stonewall immunogenic attrition and apoptosis by various means. Some of these biomarkers, namely immune-checkpoints, have recently been exploited as druggable targets in osteosarcoma and many other different cancers. These promising strides made by the use of reinvigorated immunotherapeutic approaches may lead to significant reduction in spinal osteosarcoma disease burden and corresponding reciprocity in increase of survival rates. In this review, we provide the background to spinal osteosarcoma, and proceed to elaborate on contribution of the complex ecology within tumor microenvironment giving arise to cancerous immune escape, which is currently receiving considerable attention. We follow this section on the tumor microenvironment by a brief history of cancer immunity. Also, we draw on the current knowledge of treatment gained from incidences of osteosarcoma at other locations of the skeleton (long bones of the extremities in close proximity to the metaphyseal growth plates) to make a case for application of immunity-based tools, such as immune-checkpoint inhibitors and vaccines, and draw attention to adverse upshots of immune-checkpoint blockers as well. Finally, we describe the novel biotechnique of CRISPR/Cas9 that will assist in treatment approaches for personalized medication.This work is funded by a grant (MPP 320133) from the American University of Beirut to Dr. Ali H. Eid

    PaLM 2 Technical Report

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    We introduce PaLM 2, a new state-of-the-art language model that has better multilingual and reasoning capabilities and is more compute-efficient than its predecessor PaLM. PaLM 2 is a Transformer-based model trained using a mixture of objectives. Through extensive evaluations on English and multilingual language, and reasoning tasks, we demonstrate that PaLM 2 has significantly improved quality on downstream tasks across different model sizes, while simultaneously exhibiting faster and more efficient inference compared to PaLM. This improved efficiency enables broader deployment while also allowing the model to respond faster, for a more natural pace of interaction. PaLM 2 demonstrates robust reasoning capabilities exemplified by large improvements over PaLM on BIG-Bench and other reasoning tasks. PaLM 2 exhibits stable performance on a suite of responsible AI evaluations, and enables inference-time control over toxicity without additional overhead or impact on other capabilities. Overall, PaLM 2 achieves state-of-the-art performance across a diverse set of tasks and capabilities. When discussing the PaLM 2 family, it is important to distinguish between pre-trained models (of various sizes), fine-tuned variants of these models, and the user-facing products that use these models. In particular, user-facing products typically include additional pre- and post-processing steps. Additionally, the underlying models may evolve over time. Therefore, one should not expect the performance of user-facing products to exactly match the results reported in this report

    Study and development of a liquid phase plasma reactor for the selective conversion of alcohols into aldehydes

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    La production d'aldéhydes à partir d’alcools, est une manière intéressante de valoriser la biomasse. Malgré l'importance économique qui en découle, les procédés utilisés aujourd'hui sont relativement peu efficaces. Il existe donc un réel besoin d'innovation dans ce secteur pour optimiser ces procédés en termes de consommation d'énergie et d'utilisation de matières premières. L'objectif de cette thèse est d'explorer une manière originale de produire des aldéhydes par décharges plasma hors équilibre en phase liquide. Plusieurs réacteurs plasma ont été développés et modélisés sous COMSOL Multiphysics. Les décharges sont générées dans de l'éthanol ou du butanol liquide pur. Deux électrodes sont immergées dans le milieu liquide, et une haute tension pulsée de 20 kV à une fréquence de 20 kHz est appliquée à l'une d'entre elles, tandis que l'autre est mise à la terre. Les décharges plasma dans l’alcool pur produisent une petite quantité d'aldéhyde ; la sélectivité est faible et reste généralement inférieure à 10 %, quelle que soit les conditions opératoires. Différents solides ont été ajoutés sous forme de poudre afin de tester l'hypothèse d'un couplage plasma/catalyse dans le réacteur. La gamma-alumine (Al2O3) ainsi que l'oxyde de titane (TiO2) donnent les meilleurs résultats en augmentant la sélectivité jusqu'à environ 40%. Cet effet significatif permet de montrer une efficacité de certains solides même si les mécanismes ne sont pas encore élucidés. De plus, lorsqu'un flux gazeux d'hélium, d'argon ou de CO2 bulle à proximité de l'électrode haute tension, la sélectivité des aldéhydes est fortement augmentée jusqu'à 80 %. Les résultats obtenus dans cette thèse montrent qu'il est possible, d'obtenir des aldéhydes de manière sélective par oxydation contrôlée des alcools en utilisant une décharge de plasma directement dans les liquides. L'ajout de certains solides ou de gaz plasma permet de moduler les mécanismes de réaction et d'éviter le craquage abondant des alcools sous forme de produits plus volatils (méthane, monoxyde de carbone etc...). Cette thèse ouvre donc des perspectives pour explorer d'autres réactions d'intérêt économique.The production of aldehydes, by oxidation or dehydrogenation of alcohols, is an interesting way of valorizing biomass. In spite of the economic importance that results from this, the processes used today are relatively inefficient. There is therefore a real need for innovation in this sector to optimize these processes in terms of energy consumption and the use of raw materials. The objective of this thesis is to explore an original way of producing aldehyde by non-equilibrium plasma discharges in liquid phase. Several plasma reactors were developed, and modeled by using COMSOL Multiphysics. The plasma discharges were generated in pure liquid ethanol or butanol. Two electrodes are immersed in the liquid medium, and a pulsed high voltage of 20 kV at a frequency of 20 kHz is applied to one of them, while the other is grounded. When the plasma discharge is ignited in pure alcohol, a small amount of aldehyde is formed. The selectivity is low and typically remains below 10% regardless of discharge parameters. Different solids were added to the reactor in powder form in order to test the hypothesis of plasma/catalysis coupling in the reactor. Gamma alumina (Al2O3) as well as titanium oxide (TiO2) give the best results and increased the selectivity up to about 40%. This significant increase enables to show an efficiency of some solids even if the mechanisms are not yet understood. Moreover, when an additional gas flow of helium, argon or CO2 is bubbling at vicinity of the high-voltage electrode, the aldehyde selectivity is greatly enhanced up to 80 % in the best conditions. The results obtained in this thesis show that it is possible under certain conditions to obtain aldehydes selectively by controlled oxidation of alcohols using plasma discharge directly into the liquids. The addition of certain solids or of plasma gas allows to modulate the reaction mechanisms and to avoid the abundant cracking of alcohols in the form of more volatile products (methane, carbon monoxide etc...). This thesis thus opens perspectives to explore other reactions of economic interest

    Étude et développement d'un réacteur plasma en phase liquide pour la conversion sélective des alcools en aldéhydes

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    The production of aldehydes, by oxidation or dehydrogenation of alcohols, is an interesting way of valorizing biomass. In spite of the economic importance that results from this, the processes used today are relatively inefficient. There is therefore a real need for innovation in this sector to optimize these processes in terms of energy consumption and the use of raw materials. The objective of this thesis is to explore an original way of producing aldehyde by non-equilibrium plasma discharges in liquid phase. Several plasma reactors were developed, and modeled by using COMSOL Multiphysics. The plasma discharges were generated in pure liquid ethanol or butanol. Two electrodes are immersed in the liquid medium, and a pulsed high voltage of 20 kV at a frequency of 20 kHz is applied to one of them, while the other is grounded. When the plasma discharge is ignited in pure alcohol, a small amount of aldehyde is formed. The selectivity is low and typically remains below 10% regardless of discharge parameters. Different solids were added to the reactor in powder form in order to test the hypothesis of plasma/catalysis coupling in the reactor. Gamma alumina (Al2O3) as well as titanium oxide (TiO2) give the best results and increased the selectivity up to about 40%. This significant increase enables to show an efficiency of some solids even if the mechanisms are not yet understood. Moreover, when an additional gas flow of helium, argon or CO2 is bubbling at vicinity of the high-voltage electrode, the aldehyde selectivity is greatly enhanced up to 80 % in the best conditions. The results obtained in this thesis show that it is possible under certain conditions to obtain aldehydes selectively by controlled oxidation of alcohols using plasma discharge directly into the liquids. The addition of certain solids or of plasma gas allows to modulate the reaction mechanisms and to avoid the abundant cracking of alcohols in the form of more volatile products (methane, carbon monoxide etc...). This thesis thus opens perspectives to explore other reactions of economic interest.La production d'aldéhydes à partir d’alcools, est une manière intéressante de valoriser la biomasse. Malgré l'importance économique qui en découle, les procédés utilisés aujourd'hui sont relativement peu efficaces. Il existe donc un réel besoin d'innovation dans ce secteur pour optimiser ces procédés en termes de consommation d'énergie et d'utilisation de matières premières. L'objectif de cette thèse est d'explorer une manière originale de produire des aldéhydes par décharges plasma hors équilibre en phase liquide. Plusieurs réacteurs plasma ont été développés et modélisés sous COMSOL Multiphysics. Les décharges sont générées dans de l'éthanol ou du butanol liquide pur. Deux électrodes sont immergées dans le milieu liquide, et une haute tension pulsée de 20 kV à une fréquence de 20 kHz est appliquée à l'une d'entre elles, tandis que l'autre est mise à la terre. Les décharges plasma dans l’alcool pur produisent une petite quantité d'aldéhyde ; la sélectivité est faible et reste généralement inférieure à 10 %, quelle que soit les conditions opératoires. Différents solides ont été ajoutés sous forme de poudre afin de tester l'hypothèse d'un couplage plasma/catalyse dans le réacteur. La gamma-alumine (Al2O3) ainsi que l'oxyde de titane (TiO2) donnent les meilleurs résultats en augmentant la sélectivité jusqu'à environ 40%. Cet effet significatif permet de montrer une efficacité de certains solides même si les mécanismes ne sont pas encore élucidés. De plus, lorsqu'un flux gazeux d'hélium, d'argon ou de CO2 bulle à proximité de l'électrode haute tension, la sélectivité des aldéhydes est fortement augmentée jusqu'à 80 %. Les résultats obtenus dans cette thèse montrent qu'il est possible, d'obtenir des aldéhydes de manière sélective par oxydation contrôlée des alcools en utilisant une décharge de plasma directement dans les liquides. L'ajout de certains solides ou de gaz plasma permet de moduler les mécanismes de réaction et d'éviter le craquage abondant des alcools sous forme de produits plus volatils (méthane, monoxyde de carbone etc...). Cette thèse ouvre donc des perspectives pour explorer d'autres réactions d'intérêt économique
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