Removal of Malachite Green Dye from Aqueous Solution by Catalytic Wet Oxidation Technique Using Ni/Kaolin as Catalyst

In this study, natural Algerian kaolin was used as a support and impregnated with nickel at different loading amounts (2 wt.%, 5 wt.%, and 7 wt.%) in order to prepare a supported catalyst. The wet impregnation technique was used in this preparation; nickel oxide (NiO) was the active phase precursor of the catalyst, and the catalysts were designated as follows: 2%, 5%, and 7% Ni/kaolin. These catalysts were put to the test in catalytic wet peroxide oxidation (CWPO) for degrading the organic contaminant malachite green dye (MG). Analytical techniques such as FTIR spectroscopy, X-ray diffraction, BET, and X-fluorescence were used to examine the structure, morphology, and chemical composition of the support and the produced catalysts. Several parameters, including temperature, catalytic dose, metal loading, hydrogen peroxide volume, and kinetic model were systematically investigated. The combination of improved parameters resulted in a significant increase in the catalytic activity, achieving a high removal rate of MG dye of 98.87%

Synthesis of Two Novel Copper (II) Complexes as Potential Inhibitors of HIV-1 Protease Enzyme: Experimental and Theoretical Investigations

In this study, we report the synthesis of two new copper complexes: [Cu(C$_{11}$H$_{7}$O$_{2}$)(SCN)(C$_{10}$H$_{8}$N$_{2}$)], denoted as (C-1), and [Cu(C$_{11}$H$_{7}$O$_{2}$) (C$_{12}$H$_{8}$N$_{2}$) Cl]·H$_{2}$O, denoted as (C-2). They are based on 2,2′-bipyridine or 1,10-phenanthroline and 2-hydroxy-1-naphtaldehyde ligands. The obtained complexes were characterized by FT-IR, UV-visible spectroscopy, and single-crystal X-ray diffraction analysis. Molecular docking was employed to predict the binding mode involved in the interaction between the two synthetic copper (II) complexes and HIV-1 protease enzyme. The X-ray structural analysis revealed that the crystal structures of both complexes are mainly stabilized by several intra- and intermolecular hydrogen bonds. The fingerprint plots associated with the Hirshfeld surfaces of both complexes clearly show that H···H interactions provide the largest contributions. According to the docking results, the synthesized complexes exhibit promising features which enable them to be bound to the HIV-protease enzyme

A transcriptomic continuum of differentiation arrest identifies myeloid interface acute leukemias with poor prognosis

Abstract: Classification of acute lymphoblastic and myeloid leukemias (ALL and AML) remains heavily based on phenotypic resemblance to normal hematopoietic precursors. This framework can provide diagnostic challenges for immunophenotypically heterogeneous immature leukemias, and ignores recent advances in understanding of developmental multipotency of diverse normal hematopoietic progenitor populations that are identified by transcriptional signatures. We performed transcriptional analyses of a large series of acute myeloid and lymphoid leukemias and detected significant overlap in gene expression between cases in different diagnostic categories. Bioinformatic classification of leukemias along a continuum of hematopoietic differentiation identified leukemias at the myeloid/T-lymphoid interface, which shared gene expression programs with a series of multi or oligopotent hematopoietic progenitor populations, including the most immature CD34+CD1a−CD7− subset of early thymic precursors. Within these interface acute leukemias (IALs), transcriptional resemblance to early lymphoid progenitor populations and biphenotypic leukemias was more evident in cases originally diagnosed as AML, rather than T-ALL. Further prognostic analyses revealed that expression of IAL transcriptional programs significantly correlated with poor outcome in independent AML patient cohorts. Our results suggest that traditional binary approaches to acute leukemia categorization are reductive, and that identification of IALs could allow better treatment allocation and evaluation of therapeutic options

A transcriptomic continuum of differentiation arrest identifies myeloid interface acute leukemias with poor prognosis

Abstract: Classification of acute lymphoblastic and myeloid leukemias (ALL and AML) remains heavily based on phenotypic resemblance to normal hematopoietic precursors. This framework can provide diagnostic challenges for immunophenotypically heterogeneous immature leukemias, and ignores recent advances in understanding of developmental multipotency of diverse normal hematopoietic progenitor populations that are identified by transcriptional signatures. We performed transcriptional analyses of a large series of acute myeloid and lymphoid leukemias and detected significant overlap in gene expression between cases in different diagnostic categories. Bioinformatic classification of leukemias along a continuum of hematopoietic differentiation identified leukemias at the myeloid/T-lymphoid interface, which shared gene expression programs with a series of multi or oligopotent hematopoietic progenitor populations, including the most immature CD34+CD1a−CD7− subset of early thymic precursors. Within these interface acute leukemias (IALs), transcriptional resemblance to early lymphoid progenitor populations and biphenotypic leukemias was more evident in cases originally diagnosed as AML, rather than T-ALL. Further prognostic analyses revealed that expression of IAL transcriptional programs significantly correlated with poor outcome in independent AML patient cohorts. Our results suggest that traditional binary approaches to acute leukemia categorization are reductive, and that identification of IALs could allow better treatment allocation and evaluation of therapeutic options

Bioinformatic study of the epigenome during T cell differentiation and leukemia

Des études récentes ont mis en évidence qu’au moins 70% du génome humain est transcrit et produit une myriade d’ARN non codants. Au début de ma thèse j’ai utilisé des données de RNA-Seq sens-spécifique pour identifier les transcrits divergents dans les tissus primaires de souris. J’ai utilisé aussi des données ChIP-Seq afin d’analyser leurs caractéristiques épigénétiques. Nous avons trouvé que la transcription divergente est associée de manière significative à des gènes liés à la régulation de la transcription et le développement.Dans un deuxième temps, je me suis intéressé à l'identification et la caractérisation des lncRNA chez l'homme. J’ai appliqué des approches statistiques pour quantifier leur expression et identifier ceux qui sont (dé)régulés dans un contexte normal ou leucémique Dans un troisième temps. Au cours de ma thèse, je me suis attaché à étudier le mécanisme moléculaire épigénomique ainsi qu'à développer un pipeline bioinformatique permettant d'identifier les gènes (codant ou non codant) associés à des profils H3K4me2/3 étendus. Ainsi, j’ai mis en évidences que ces profils étendus étaient directement dépendants d'un processus transcriptionelle impliquant des nouveaux mécanismes de régulation. Cette étude a donné aussi lieu à une publication dont je suis cosignataire en premier auteur. (Zacarias, Belhocine et al. Journal of Immunology 2015). Cette nouvelle approche devrait s'avérer très utile dans d'autres modèles développementaux et/ou pathologiques et peuvent être utilisé comme outil de prioritisation des candidats les plus relevant dans des approches plus globale.Recent studies indicate that at least 70% of the human genome is transcribed into a myriad of both coding and non-coding RNAs. at the beginning of my thesis I used RNA-Seq data to identify divergent transcripts in mouse primary tissues. I also used the ChIP-Seq data to analyze their epigenetic characteristics. The results demonstrated that divergent transcription was significantly associated with genes related to transcription regulation and development. In a second phase, I was interested in the LncRNAs identification and characterization during the development of human T lymphocytes and in T acute lymphoblastic leukemia (T-ALL). I applied statistical approaches to quantify their expression and identify those that are regulated in a normal or leukemic contextSubsequently, I determined the most appropriate approach to prioritize the functional role of LncRNAs. Indeed, I focused on studying the molecular epigenomic mechanism marking and developed a bioinformatics pipeline to identify genes (coding or non-coding) associated with the extended profiles of H3K4me2/3. Evidence generated through the pipeline demonstrated that these extended profiles were directly dependent on specific transcriptional process involving new regulatory mechanisms.In conclusion, this body of work has resulted in a more comprehensive approach to determining the true functional role of LncRNAs in both normal biological context and in human disease

Modeling and structural analysis of power systems dynamic model

Cette thèse traite des problématiques relatives à la modélisation, l’analyse et la simulation des systèmes électriques interconnectés. Elle a été principalement motivée par le besoin de comprendre et de clarifier les niveaux de modélisation de certains composants électriques comme les lignes de transmission ainsi que leur habilité à reproduire les différents phénomènes qui présentent un intérêt dans le système. En effet, pour faciliter les études et les simulations, les modèles les plus détaillés et les plus complexes sont généralement remplacés par des modèles plus simples selon le type des phénomènes visés. Usuellement, la structure dynamique de l’ensemble du système n’est pas prise en compte dans l’étape de simplification, ce qui fait que, dans la plupart du temps, des validations expérimentales sont nécessaires. C’est pourquoi un cadre structurel et une vision systémique sont proposés dans cette thèse afin d’apporter des solutions plus générales et plus fiables qui s’adaptent mieux à l’approximation des systèmes électriques. Le cadre proposé il nous a permis : d’une part, d’expliquer par le biais de la réduction l’approximation du modèle à paramètres distribués d’une ligne par un modèle plus simple de dimension finie appelé π et d’autre part, d’étendre les investigations à une échelle plus grande où une nouvelle méthodologie de troncature est proposée pour l’approximation des modèles dynamiques de grande taille. Elle se distingue des méthodes standards par l’efficacité d’évaluation des dynamiques du système même dans des situations particulières ainsi que la prise en compte de divers besoins pratiques. Il s’agit d’une approche mixte qui combine, d’une part, le principe de la troncature modale et, d’autre part, l’énergie de la réponse impulsionnelle afin de préserver les structures dynamique et physique du système. A cela s’ajoute également la question du nombre et choix des entrées des systèmes à paramètres distribués qui est posée ici d’un point de vue de l’automatique afin de lui donner plus d’utilité pratique, surtout dans les simulateurs numériques. L’approche utilisée à cet effet est algébrique, et la contribution est une étude assez détaillée de l’état de l’art sur le sujet qui a finalement affiné d’avantage la problématique et conduit à de nouvelles pistes plus prometteuses car la question est jusqu’alors partiellement résolue. Plus précisément, les investigations doivent se concentrer désormais sur les commandes dites aux bords ou frontières.D’un point de vue pratique, les résultats obtenus dans cette thèse peuvent être exploités dans l’avenir pour améliorer et facilité les techniques actuelles de simulation et d’analyse en adaptant, par exemple, chaque modèle utilisé aux phénomènes à reproduire.This thesis was motivated by the need to better understand the connection between the models used in simulation of the power systems dynamics and the phenomena which have to be analyzed or reproduced by the simulation. Indeed, to study and to simulate the behavior of the interconnected power systems, the sophisticated models such as the one of the transmission lines are generally replaced by simple ones. Usually, a dynamic structure of the whole system is not taken into account in a simplification step. As a consequence, experimental validations are generally needed to assess the result of the approximation. For this reason, a structural framework and a systemic viewpoint are proposed to make the solutions more general and more appropriate to the approximation of power systems. First, this allows explaining the link between the distributed parameters model of the transmission lines and the finite dimensional one called π model based on the model reduction. Next, a novel mixed approximation methodology for large-scale dynamic models is proposed which allows one to better rate the dynamics of the system in different situations, and to take into account several practical needs. This methodology is based on a mixture between the modal truncation and the energy of the impulse response so that the dynamical and the physical structures of the system remain unchanged. Moreover, in the context of the automatic control theory, the issue related to a number and a choice of input variables for distributed parameters systems is discussed. To address this issue, an algebraic approach is applied. Here, the main contribution is the detailed study conducted on the basis of the state of the art by which a new way is proposed. Because the issue is not fully solved, more investigations have to be focused on the so called boundary control variables. For practical applications, all the results presented in this study can be exploited to further improve numerical simulations and behavioral studies of large-scale power systems

Modélisation et analyse structurelle du fonctionnement dynamique des systèmes électriques

This thesis was motivated by the need to better understand the connection between the models used in simulation of the power systems dynamics and the phenomena which have to be analyzed or reproduced by the simulation. Indeed, to study and to simulate the behavior of the interconnected power systems, the sophisticated models such as the one of the transmission lines are generally replaced by simple ones. Usually, a dynamic structure of the whole system is not taken into account in a simplification step. As a consequence, experimental validations are generally needed to assess the result of the approximation. For this reason, a structural framework and a systemic viewpoint are proposed to make the solutions more general and more appropriate to the approximation of power systems. First, this allows explaining the link between the distributed parameters model of the transmission lines and the finite dimensional one called π model based on the model reduction. Next, a novel mixed approximation methodology for large-scale dynamic models is proposed which allows one to better rate the dynamics of the system in different situations, and to take into account several practical needs. This methodology is based on a mixture between the modal truncation and the energy of the impulse response so that the dynamical and the physical structures of the system remain unchanged. Moreover, in the context of the automatic control theory, the issue related to a number and a choice of input variables for distributed parameters systems is discussed. To address this issue, an algebraic approach is applied. Here, the main contribution is the detailed study conducted on the basis of the state of the art by which a new way is proposed. Because the issue is not fully solved, more investigations have to be focused on the so called boundary control variables. For practical applications, all the results presented in this study can be exploited to further improve numerical simulations and behavioral studies of large-scale power systems.Cette thèse traite des problématiques relatives à la modélisation, l’analyse et la simulation des systèmes électriques interconnectés. Elle a été principalement motivée par le besoin de comprendre et de clarifier les niveaux de modélisation de certains composants électriques comme les lignes de transmission ainsi que leur habilité à reproduire les différents phénomènes qui présentent un intérêt dans le système. En effet, pour faciliter les études et les simulations, les modèles les plus détaillés et les plus complexes sont généralement remplacés par des modèles plus simples selon le type des phénomènes visés. Usuellement, la structure dynamique de l’ensemble du système n’est pas prise en compte dans l’étape de simplification, ce qui fait que, dans la plupart du temps, des validations expérimentales sont nécessaires. C’est pourquoi un cadre structurel et une vision systémique sont proposés dans cette thèse afin d’apporter des solutions plus générales et plus fiables qui s’adaptent mieux à l’approximation des systèmes électriques. Le cadre proposé il nous a permis : d’une part, d’expliquer par le biais de la réduction l’approximation du modèle à paramètres distribués d’une ligne par un modèle plus simple de dimension finie appelé π et d’autre part, d’étendre les investigations à une échelle plus grande où une nouvelle méthodologie de troncature est proposée pour l’approximation des modèles dynamiques de grande taille. Elle se distingue des méthodes standards par l’efficacité d’évaluation des dynamiques du système même dans des situations particulières ainsi que la prise en compte de divers besoins pratiques. Il s’agit d’une approche mixte qui combine, d’une part, le principe de la troncature modale et, d’autre part, l’énergie de la réponse impulsionnelle afin de préserver les structures dynamique et physique du système. A cela s’ajoute également la question du nombre et choix des entrées des systèmes à paramètres distribués qui est posée ici d’un point de vue de l’automatique afin de lui donner plus d’utilité pratique, surtout dans les simulateurs numériques. L’approche utilisée à cet effet est algébrique, et la contribution est une étude assez détaillée de l’état de l’art sur le sujet qui a finalement affiné d’avantage la problématique et conduit à de nouvelles pistes plus prometteuses car la question est jusqu’alors partiellement résolue. Plus précisément, les investigations doivent se concentrer désormais sur les commandes dites aux bords ou frontières.D’un point de vue pratique, les résultats obtenus dans cette thèse peuvent être exploités dans l’avenir pour améliorer et facilité les techniques actuelles de simulation et d’analyse en adaptant, par exemple, chaque modèle utilisé aux phénomènes à reproduire

A new approximation methodology for linear multivariable large-scale systems

International audienceA new approximation methodology is proposed in this paper to reduce the dynamic models of linear multivariable dynamic systems with slow decay of Hankel spectrum. The main problem is that for such systems, the dynamics are difficult to evaluate using directly the classic indexes like the energy of the state variables or the residues related to the modes and the existing techniques may not give always satisfactory results. For this, we propose here a mixed approach based on the energy of the impulse response and the link between the modes and the states to better evaluate the dynamics and finally reduce the model. This preserves the dynamic structure of the system and allows one to obtain acceptable results with reduced models of much lower order than the ones obtained by the classic approaches. Theoretical results are first presented and a power system practical example is next treated to validate our methodology

A mix balanced-modal truncations for power systems model reduction

International audience— In this paper, a new model reduction technique mixing the balanced and modal truncations is proposed for power systems. Usually, only the power transmission lines are approximated such that, when used with the rest of the power system, the phenomena of interest are reproduced. Our approach is structural since it is based on the reduction techniques of the dynamical systems and consider the full power system rather than the lines alone. It is shown that, to obtain a good approximation with the balanced or modal truncations, a large number of dynamics are needed to be kept in the reduced model. By mixing the balanced and modal truncations, a much lower order reduced model is obtained and the behaviour of the full system is faithfully reproduced. This result is useful in practice since it opens the way to improve the numerical simulations and behaviour analysis of power systems by making easy the digital implementations. This new technique is checked by simulation tests in Matlab and EMTP