Academic literature on the topic 'Système de triple de Lie'

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Journal articles on the topic "Système de triple de Lie"

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Lohe, M. A. "Higher-order synchronization on the sphere." Journal of Physics: Complexity 3, no. 1 (December 29, 2021): 015003. http://dx.doi.org/10.1088/2632-072x/ac42e1.

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Abstract We construct a system of N interacting particles on the unit sphere S d − 1 in d-dimensional space, which has d-body interactions only. The equations have a gradient formulation derived from a rotationally-invariant potential of a determinantal form summed over all nodes, with antisymmetric coefficients. For d = 3, for example, all trajectories lie on the two-sphere and the potential is constructed from the triple scalar product summed over all oriented two-simplices. We investigate the cases d = 3, 4, 5 in detail, and find that the system synchronizes from generic initial values for both positive and negative coupling coefficients, to a static final configuration in which the particles lie equally spaced on S d − 1 . Completely synchronized configurations also exist, but are unstable under the d-body interactions. We compare the relative effect of two-body and d-body forces by adding the well-studied two-body interactions to the potential, and find that higher-order interactions enhance the synchronization of the system, specifically, synchronization to a final configuration consisting of equally spaced particles occurs for all d-body and two-body coupling constants of any sign, unless the attractive two-body forces are sufficiently strong relative to the d-body forces. In this case the system completely synchronizes as the two-body coupling constant increases through a positive critical value, with either a continuous transition for d = 3, or discontinuously for d = 5. Synchronization also occurs if the nodes have distributed natural frequencies of oscillation, provided that the frequencies are not too large in amplitude, even in the presence of repulsive two-body interactions which by themselves would result in asynchronous behaviour.
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Hodge, Terrell L. "Lie Triple Systems, Restricted Lie Triple Systems, and Algebraic Groups." Journal of Algebra 244, no. 2 (October 2001): 533–80. http://dx.doi.org/10.1006/jabr.2001.8890.

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Asif, Sania, and Zhixiang Wu. "Generalized Lie Triple Derivations of Lie Color Algebras and Their Subalgebras." Symmetry 13, no. 7 (July 16, 2021): 1280. http://dx.doi.org/10.3390/sym13071280.

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Consider a Lie color algebra, denoted by L. Our aim in this paper is to study the Lie triple derivations TDer(L) and generalized Lie triple derivations GTDer(L) of Lie color algebras. We discuss the centroids, quasi centroids and central triple derivations of Lie color algebras, where we show the relationship of triple centroids, triple quasi centroids and central triple derivation with Lie triple derivations and generalized Lie triple derivations of Lie color algebras L. A classification of Lie triple derivations algebra of all perfect Lie color algebras is given, where we prove that for a perfect and centerless Lie color algebra, TDer(L)=Der(L) and TDer(Der(L))=Inn(Der(L)).
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Asif, Sania, Lipeng Luo, Yanyong Hong, and Zhixiang Wu. "Conformal Triple Derivations and Triple Homomorphisms of Lie Conformal Algebras." Algebra Colloquium 30, no. 02 (June 2023): 263–80. http://dx.doi.org/10.1142/s1005386723000214.

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Let [Formula: see text] be a finite Lie conformal algebra. We investigate the conformal derivation algebra [Formula: see text], conformal triple derivation algebra [Formula: see text] and generalized conformal triple derivation algebra [Formula: see text], focusing mainly on the connections among these derivation algebras. We also give a complete classification of (generalized) conformal triple derivation algebras on all finite simple Lie conformal algebras. In particular, [Formula: see text], where [Formula: see text] is a finite simple Lie conformal algebra. But for [Formula: see text], we obtain a conclusion that is closely related to [Formula: see text]. Finally, we introduce the definition of a triple homomorphism of Lie conformal algebras. Triple homomorphisms of all finite simple Lie conformal algebras are also characterized.
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Biyogmam, Guy Roger. "LIE CENTRAL TRIPLE RACKS." International Electronic Journal of Algebra 17, no. 17 (June 1, 2015): 58. http://dx.doi.org/10.24330/ieja.266212.

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Li, Hailing, and Ying Wang. "Generalized Lie triple derivations." Linear and Multilinear Algebra 59, no. 3 (March 2011): 237–47. http://dx.doi.org/10.1080/03081080903350153.

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García, Esther, Miguel Gómez Lozano, and Erhard Neher. "Nondegeneracy for Lie Triple Systems and Kantor Pairs." Canadian Mathematical Bulletin 54, no. 3 (September 1, 2011): 442–55. http://dx.doi.org/10.4153/cmb-2011-023-9.

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AbstractWe study the transfer of nondegeneracy between Lie triple systems and their standard Lie algebra envelopes as well as between Kantor pairs, their associated Lie triple systems, and their Lie algebra envelopes. We also show that simple Kantor pairs and Lie triple systems in characteristic 0 are nondegenerate.
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Smirnov, O. N. "Imbedding of Lie triple systems into Lie algebras." Journal of Algebra 341, no. 1 (September 2011): 1–12. http://dx.doi.org/10.1016/j.jalgebra.2011.06.011.

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Brešar, M., M. Cabrera, M. Fošner, and A. R. Villena. "Lie triple ideals and Lie triple epimorphisms on Jordan and Jordan–Banach algebras." Studia Mathematica 169, no. 3 (2005): 207–28. http://dx.doi.org/10.4064/sm169-3-1.

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DONG, YAN-QIN, QING-CHENG ZHANG, and YONG-ZHENG ZHANG. "RESTRICTED AND QUASI-TORAL RESTRICTED LIE TRIPLE SYSTEMS." Journal of Algebra and Its Applications 11, no. 05 (September 26, 2012): 1250093. http://dx.doi.org/10.1142/s0219498812500934.

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In this paper, we first discuss the nilpotency of restricted Lie triple systems and the condition of existence of p-mappings on Lie triple systems. Second, we devote our attention to prove the uniqueness of the decomposition as a direct sum of p-ideals of a restricted Lie triple system. Finally, we study how a quasi-toral restricted Lie triple system T with zero center and of minimal dimension should be.
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Dissertations / Theses on the topic "Système de triple de Lie"

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Ricciardo, Antonio. "Lie algebras and triple systems." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8712/.

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This thesis is dedicated to the Tits-Kantor-Koecher (TKK) construction which establishes a bijective correspondence between unital Jordan algebras and shortly graded Lie algebras with Z-grading induced by an sl_2-triple. It is based on the observation that if g is a Lie algebra with a short Z-grading and f lies in g_1, then the formula ab=[[a,f],b] defines a structure of a Jordan algebra on g_{-1}. The TKK construction has been extended to Jordan triple systems and, more recently, to the so-called Kantor triple systems. These generalizations are studied in the thesis.
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Hidri, Samiha. "Formes bilinéaires invariantes sur les algèbres de Leibniz et les systèmes triples de Lie (resp. Jordan)." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0237/document.

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Dans cette thèse, on étudie la structure de quelques types d'algèbres (binaires et ternaires) munies d'une forme bilinéaire symétrique, non dégénérée et associative (ou invariante). La première partie de cette thèse est consacrée à l'étude des algèbres de Leibniz quadratiques. On montre que ces algèbres sont symétriques. De plus, on utilise la T*-extension et la double extension pour montrer plusieurs résultats sur ce type d'algèbres. Ensuite, on a remarqué que l'anti-commutativité du crochet de Lie donne naissance à de nouveaux types d'invariance pour les algèbres de Leibniz : L'invariance à gauche et l'invariance à droite. Alors, on s'est intéresse à l'étude des algèbres de Leibniz (gauche et droite) munies d'une forme bilinéaire symétrique, non dégénérée et invariante à gauche (et invariante à droite). On prouve que ces algèbres sont Lie admissibles. En second lieu, on s'intéresse aux systèmes triples de Lie et de Jordan. On débute la deuxième partie de cette thèse par la description inductive des systèmes triples de Lie quadratiques au moyen de la double extension. En plus, on introduit la T*extension des systèmes triples de Jordan pseudo-Euclidien. Finalement, on donne deux nouvelles caractérisations des systèmes triples de Jordan semi-simples parmi les systèmes triples de Jordan pseudo-Euclidiens
In this thesis, we study the stucture of several types of algebras endowed with Symmetric, non degenerate and invariant bilinear forms. In the first part, we study quadratic Leibniz algebras. First, we prove that these algebras are symmetric. Then, we use the T*-extension and the double extension to prove some properties of this type of Leibniz algebras. Besides, since we observe that the skew-symmetry of the Leibniz bracket gives rise to other types of invariance for a bilinear form on a Leibniz algebra: The left invariance and the right invariance. We focus on the study of left (resp. right) Leibniz algebras with symmetric, non degenerate and left (resp. right) invariant bilinear form. In particular, we prove that these algebras are Lie admissibles. The second part of this work is dedicated to the study of quadratic Lie triple systems and pseudo-euclidien Jordan triple systems. We start by giving an inductive description of quadratic Lie triple systems using double extension. Next, we introduce the T*-extension of Jordan triple systems. Finally, we give new caracterizations of semi-simple Jordan triple systems among pseudo-euclidian Jordan triple systems
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Hidri, Samiha. "Formes bilinéaires invariantes sur les algèbres de Leibniz et les systèmes triples de Lie (resp. Jordan)." Electronic Thesis or Diss., Université de Lorraine, 2016. http://www.theses.fr/2016LORR0237.

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Dans cette thèse, on étudie la structure de quelques types d'algèbres (binaires et ternaires) munies d'une forme bilinéaire symétrique, non dégénérée et associative (ou invariante). La première partie de cette thèse est consacrée à l'étude des algèbres de Leibniz quadratiques. On montre que ces algèbres sont symétriques. De plus, on utilise la T*-extension et la double extension pour montrer plusieurs résultats sur ce type d'algèbres. Ensuite, on a remarqué que l'anti-commutativité du crochet de Lie donne naissance à de nouveaux types d'invariance pour les algèbres de Leibniz : L'invariance à gauche et l'invariance à droite. Alors, on s'est intéresse à l'étude des algèbres de Leibniz (gauche et droite) munies d'une forme bilinéaire symétrique, non dégénérée et invariante à gauche (et invariante à droite). On prouve que ces algèbres sont Lie admissibles. En second lieu, on s'intéresse aux systèmes triples de Lie et de Jordan. On débute la deuxième partie de cette thèse par la description inductive des systèmes triples de Lie quadratiques au moyen de la double extension. En plus, on introduit la T*extension des systèmes triples de Jordan pseudo-Euclidien. Finalement, on donne deux nouvelles caractérisations des systèmes triples de Jordan semi-simples parmi les systèmes triples de Jordan pseudo-Euclidiens
In this thesis, we study the stucture of several types of algebras endowed with Symmetric, non degenerate and invariant bilinear forms. In the first part, we study quadratic Leibniz algebras. First, we prove that these algebras are symmetric. Then, we use the T*-extension and the double extension to prove some properties of this type of Leibniz algebras. Besides, since we observe that the skew-symmetry of the Leibniz bracket gives rise to other types of invariance for a bilinear form on a Leibniz algebra: The left invariance and the right invariance. We focus on the study of left (resp. right) Leibniz algebras with symmetric, non degenerate and left (resp. right) invariant bilinear form. In particular, we prove that these algebras are Lie admissibles. The second part of this work is dedicated to the study of quadratic Lie triple systems and pseudo-euclidien Jordan triple systems. We start by giving an inductive description of quadratic Lie triple systems using double extension. Next, we introduce the T*-extension of Jordan triple systems. Finally, we give new caracterizations of semi-simple Jordan triple systems among pseudo-euclidian Jordan triple systems
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Hajjaji, Atef. "Étude des opérateurs de Rota-Baxter relatifs sur les algèbres ternaires de type Lie et Jordan." Electronic Thesis or Diss., Mulhouse, 2024. http://www.theses.fr/2024MULH7172.

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L'objectif de cette thèse est d'étudier les opérateurs de Rota-Baxter relatifs sur les algèbres ternaires de type Lie et de type Jordan. L'étude porte sur leur structure, leur cohomologie, leurs déformations et leur lien avec les équations de Yang-Baxter. Ce travail est divisé en trois parties. La première partie est consacrée à l'étude de l'algèbre de contrôle des systèmes triples de Lie, et à son application à la théorie existante de la cohomologie. De plus, nous introduisons la notion d'opérateur de Rota-Baxter relatif sur les systèmes triples de Lie et construisons une 3-algèbre de Lie comme cas spécial des L∞-algèbres dont les éléments de Maurer-Cartan sont des opérateurs de Rota-Baxter relatifs. Dans la deuxième partie, nous introduisons la notion d'opérateur de Rota-Baxter relatif twisté sur les algèbres 3-Lie et construisons une L∞-algèbre dont les éléments de Maurer-Cartan sont des opérateurs de Rota-Baxter relatifs twistés. Cela nous permet de définir la cohomologie de Chevalley-Eilenberg d'un opérateur de Rota-Baxter relatif twisté. Dans la dernière partie, nous étudions la représentation des algèbres ternaires de Jordan, ce qui nous permet d'introduire la notion d'algèbres ternaires de Jordan cohérentes. Ensuite, les opérateurs de Rota-Baxter relatifs des algèbres ternaires de Jordan sont introduits et les solutions de l'équation de Yang-Baxter de Jordan ternaire sont discutées en impliquant des opérateurs de Rota-Baxter relatifs
The goal of this thesis is to explore relative Rota-Baxter operators in the context of ternary algebras of both Lie and Jordan types. We mainly consider Lie triple systems, 3-Lie algebras and ternary Jordan algebras. The study covers their structure, cohomology, deformations, and their connection with the Yang-Baxter equations. The work is divided into three main parts. The first part aims first to introduce and study a graded Lie algebra whose Maurer-Cartan elements are Lie triple systems. It turns out to be the controlling algebra of Lie triple systems deformations and fits with the adjoint cohomology theory of Lie triple systems introduced by Yamaguti. In addition, we introduce the notion of relative Rota-Baxter operators on Lie triple systems and construct a Lie 3-algebra as a special case of L∞-algebras, where the Maurer-Cartan elements correspond to relative Rota-Baxter operators. In the second part, we introduce the concept of twisted relative Rota-Baxter operators on 3-Lie algebras and construct an L∞-algebra, where the Maurer-Cartan elements are twisted relative Rota-Baxter operators. This allows us to define the Chevalley-Eilenberg cohomology of a twisted relative Rota-Baxter operator. In the last part, we deal with a representation theory of ternary Jordan algebras. In particular, we introduce and discuss the concept of coherent ternary Jordan algebras. We then define relative Rota-Baxter operators for ternary Jordan algebras and discuss solutions ofthe ternary Jordan Yang-Baxter equation involving relative Rota-Baxter operators. Moreover, we investigate ternary pre-Jordan algebras as the underlying algebraic structure of relative Rota-Baxter operators
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Ciucasu, Cristian. "Système à absorption à triple-effet pour la climatisation." Paris, ENMP, 1998. http://www.theses.fr/1998ENMP0840.

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La these est centree autour de trois objectifs : l'optimisation du cycle triple-effet a eau-ammoniac, l'etude locale du fonctionnement de l'absorbeur, la realisation d'une premiere etape de l'installation experimentale. Une analyse economique et environnementale definit le niveau des performances energetiques a atteindre pour que le procede d'absorption soit competitif vis-a-vis des machines a compression. Les choix de l'architecture du systeme et du couple frigorigene-absorbant sont bases sur l'etude des cycles multi-etages envisageables pour les applications de climatisation. Le systeme etudie comporte plusieurs elements nouveaux qui permettent de diminuer la consommation d'energie thermique. Un logiciel est elabore pour le calcul des grandeurs thermodynamiques a partir des donnees du cahier des charges. Il repose sur deux elements originaux : l'identification correcte des parametres et des equations, l'imposition des pincements de temperature en accord avec la realite physique. La methode d'integration thermique de linnhoff est utilisee pour choisir l'architecture optimale du point de vue energetique. Une etude d'optimisation met en evidence le jeu de parametres qui maximise le rendement de l'installation. La qualite des transformations energetiques est examinee dans le cadre d'une analyse entropique du cycle. Un modele de calcul numerique pour les regimes stationnaires de l'absorbeur a film tombant est developpe. Il resulte d'une analyse de la dynamique de l'ecoulement et des phenomenes de transport de matiere et d'energie. Le logiciel elabore permet d'etudier la variation des grandeurs physiques a l'interieur de l'echangeur et de determiner son comportement dans diverses conditions de fonctionnement. Le dimensionnement est effectue pour tous les composants d'une machine de faible puissance frigorifique. Dans cette phase du projet seule la boucle basse pression a ete realisee. Les resultats experimentaux permettent de valider deux modeles de calcul.
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Koufany, Khalid. "Analyse et géométrie des domaines bornés symétriques." Habilitation à diriger des recherches, Université Henri Poincaré - Nancy I, 2006. http://tel.archives-ouvertes.fr/tel-00138557.

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Ce mémoire présente un point de vue basé sur la théorie des algèbres de Jordan pour faire une étude analytique, géométrique et topologique de certains espaces homogènes : espaces hermitiens symétriques, leurs frontières de Shilov et espaces symétriques causaux de type Cayley.
En particulier, nous passons en revue des résultats sur l'indice de Maslov, de Souriau et d'Arnold-Leray. Nous étudions aussi certaines propriétés de contractions et de compressions de ces espaces.
Le prolongement de la série discrète holomorphe est une partie importante du programme de Gelfand-Gindikin. Dans ce contexte, nous étudions les espaces de Hardy des fonctions holomorphes sur certains domaines Stein. Nous donnons en particulier le lien qui existe entre ces espaces de Hardy et les espaces de Hardy classiques des fonctions holomorphes sur les espaces hermitiens symétriques.
En dernier lieu, nous étudions la conjecture de Helgason pour la frontière de Shilov des espaces hermitiens symétriques. Plus précisément, nous caractérisons l'image par de la transformation de Poisson des hyperfonctions et des fonctions $L^p$ sur la frontière de Shilov.
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Vandebrouck, Fabrice. "Analyse fonctionnelle sur les domaines bornés symétriques et systèmes triples de Jordan." Poitiers, 1999. http://www.theses.fr/1999POIT2251.

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La theorie des systemes triples de jordan hermitiens positifs apparait comme un outil utile pour etudier la geometrie ou l'analyse sur les domaines bornes symetriques. Cette these presente une description geometrique du groupe des automorphismes analytiques d'un tel domaine et acheve la description explicite de son algebre de lie en termes de champs de vecteurs holomorphes. En particulier, la description de la decomposition radicielle en termes de decomposition de peirce mene a une caracterisation du groupe d'iwasawa comme le stabilisateur de composantes holomorphes du bord du domaine. On introduit la transformation de cayley entre le domaine et un domaine de siegel pour generaliser les coordonnees horocycliques connues pour les domaines matriciels. On montre geometriquement comment domaines de siegel et cones symetriques sont des orbites de groupes. Utilisant les fonctions puissances connues pour les cones symetriques, on construit les equations horocycliques. On obtient ainsi, pour les domaines de type tube, des expressions explicites pour les fonctions propres des operateurs differentiels invariants sur le domaine et pour le noyau de poisson-furstenberg en termes de norme generique et de quasi-inverse. On donne une construction elementaire d'un systeme de generateurs pour cette algebre d'operateurs, sans utiliser la classification. Cela mene a une caracterisation des fonctions harmoniques sur le domaine. On termine en retrouvant des resultats sur les equations de hua, les preuves etant toujours dans le formalisme des systemes triples de jordan.
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Hao, Kuangrong. "Algèbre de Lie et cinématique des mécanismes en boucles fermées." Phd thesis, Ecole Nationale des Ponts et Chaussées, 1995. http://pastel.archives-ouvertes.fr/pastel-00569136.

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L'objectif de cette thèse est l'étude du comportement cinématique des mécanismes bouclés de corps rigides. Le modèle mathématique d'un tel mécanisme est l'équation de fermeture f (q1,..., qm) = e où q1,...,qm sont des coordonnées articulaires et f est une fonction analytique à valeur dans un groupe de Lie. L'étude des propriétés cinématiques se ramène à celle de l'ensemble des configurations admissibles f-1 ( e ) qui est une sous-variété dans le cas régulier où f est une subimmersion. Par contre, l'étude est beaucoup plus difficile lorsque f possède des singularités. On utilise comme outil fondamental le formalisme de la géométrie différentielle des groupes de Lie pour le groupe des déplacements et la structure de Δ - module de son algèbre de Lie, ceci permet une écriture simple et condensée des équations de la cinématique et facilite leur traitement symbolique. Nous avons montré que l'analyse au deuxième ordre de l'équation de fermeture est suffisante pour les mécanismes 6R paradoxaux. Un algorithme d'évaluation du rang d'un ensemble de champs antisymétriques (équiprojectifs) est développé et est utilisé pour étudier les processus de génération des sous algèbres de Lie. Nous avons proposé également des méthodes de cinématique inverse pour des mécanismes spatiaux, ces méthodes permettent de résoudre l'équation de fermeture indépendamment d'un choix des coordonnées et d'obtenir des conditions nécessaires et suffisantes de résolution : notamment, la méthode simplifie considérablement la procédure de résolution pour les mécanismes 6R spatiaux.
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Mabrouk, Nesrine. "Effet anti-tumoral du GTN +/- doxorubicine dans le cancer du sein triple négatif : implication du système immunitaire." Thesis, Bourgogne Franche-Comté, 2021. https://nuxeo.u-bourgogne.fr/nuxeo/site/esupversions/1f1d033c-28a0-48c8-a8c4-e49ea46a9f18.

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Le cancer du sein (CS) est une maladie hautement complexe, hétérogène et multifactorielle. Comparé aux autres sous-types, le cancer du sein triple négatif (CSTN) représente l'un des stades les plus avancés de la maladie, et se caractérise par une forte hétérogénéité inter et intra-tumorale et une charge mutationnelle élevée, rendant les traitements très difficiles et inefficaces. L’absence d’expression des récepteurs aux œstrogènes, à la progestérone, et l’absence de surexpression du récepteur HER2, fait des chimiothérapies (exemple : la doxorubicine) adjuvantes ou néo adjuvantes, le traitement de référence chez les patients atteints de ce type de cancer. Malheureusement, le taux de réponse anatomopathologique complète en réponse à ces chimiothérapies, dépasse rarement les 50 % avec un bénéfice à long terme qui touche uniquement 30 à 50% des malades. Le laboratoire LIIC dans lequel j’ai effectué ma thèse a comme objectif de montrer qu’un donneur de monoxyde d’azote (NO), le glycéryl trinitritrate (GTN), médicament utilisé en cardiologie, peut améliorer l’efficacité thérapeutique des chimiothérapies anti-cancéreuses. Le but de mon projet de thèse consistait donc à déterminer si l’association du GTN à la doxorubicine pouvait potentialiser l’activité anti-tumorale de cette chimiothérapie dans le CSTN, et de déterminer le mécanisme par lequel cette combinaison agit en mettant l’accent sur le microenvironnement immunitaire en général, et plus particulièrement sur les cellules myéloïdes immunosuppressives, les MDSCs.Les résultats ont montré que l’association du GTN à la doxorubicine améliorait significativement l'efficacité anti-tumorale de cette dernière, dans un modèle de CSTN induit par l’injection de cellules mammaires 4T1. Cet effet est dû, en partie, à la capacité du GTN à augmenter la différenciation des LTCD4+ vers le sous-type anti-tumorale Th1, à augmenter le recrutement intra-tumoral des cellules CD8+/PD-1+ et des G-MDSCs sous-exprimant PD-L1. Cependant, le mécanisme principal par lequel le GTN agit repose essentiellement sur sa capacité à reprogrammer, en présence des ROS, ces G-MDSCs en faveur d’une diminution de leur activité immunosuppressive. En effet, les résultats ont révélé que le GTN, via la S-nitrosylation de STAT5, était capable de moduler le métabolisme lipidique, dépendant de la protéine FATP2 (Fatty Acid Transport Protein 2) de ces cellules. Ainsi une diminution de FATP2, ainsi que de tous les composants faisant partie de la voie de signalisation de cette protéine, en amont (STAT5) et en aval (PGE2), a été observée en réponse au GTN +/- doxorubicine. Tous ces effets étaient inhibés en présence d’un inhibiteur de ROS, la N-acétyl cystéines (NAC). La NAC retardait également considérablement la progression tumorale lorsqu’elle est associée à la combinaison doxorubicine / GTN.Ce travail, basé sur l’utilisation de deux molécules couramment utilisées en clinique, ouvre sans conteste une nouvelle perspective de traitement pour les patientes atteintes d’un cancer TN et cette combinaison pourra être rapidement proposée aux cliniciens
Breast cancer (BC) is a highly complex, heterogeneous and multifactorial disease. Compared to other subtypes, triple negative (TNBC) represents one of the most advanced stages of the disease, and is characterized by a strong inter- and intra-tumor heterogeneity and a high mutational burden, making treatments very difficult and inefficient. The absence of estrogen and progesterone receptors expression, and the absence of HER2 receptor overexpression, makes chemotherapy (example: doxorubicin), the prior treatment in patients with this type of BC. Unfortunately, the complete anatomopathological response rate, in response to these chemotherapies, rarely exceeds 50% with a long-term benefit affecting only 30 to 50% of patients. The LIIC laboratory in which I did my thesis aims to show that a donor of nitric oxide (NO), glyceryl trinitritrate (GTN), a drug used in cardiology, can improve the therapeutic efficacy of anti-cancerous chemotherapy. The aim of my thesis project was therefore to determine whether the association of GTN with doxorubicin could potentiate the antitumor activity of this chemotherapy in TNBC, and to determine the mechanism by which this combination acts by emphasizing the immune microenvironment in general, and more particularly on immunosuppressive myeloid cells, MDSCs.The results showed that the association of GTN with doxorubicin significantly improved the anti-tumor efficacy of this chemotherapy, in a TNBC model induced by the injection of 4T1 breast cells. This effect is due, in part, to the ability of GTN to increase the differentiation of LTCD4 + in the anti-tumor linage Th1, to increase the intra-tumor recruitment of CD8 + / PD-1 + cells and of G-MDSCs down-expressing PD-L1. Nevertheless, the main mechanism by which GTN acts is essentially based on its ability to reprogram, in the presence of ROS, these G-MDSCs towards a less immunosuppressive phenotype. Indeed, the results revealed that GTN, via the S-nitrosylation of STAT5, was able to modulate the lipid metabolism of these cells, which is dependent on the protein FATP2 (Fatty Acid Transport Protein 2). Thus, a decrease in FATP2, as well as all the upstream (STAT5) and downstream (PGE2) components of this signaling pathway was observed in response to GTN +/- doxorubicin. All of these effects were inhibited in the presence of an ROS inhibitor, the N-acetyl cysteines (NAC). NAC also significantly delayed tumor progression when used in combination with doxorubicin / GTN.This work, based on the use of two molecules commonly used in the clinic, undoubtedly opens up a new treatment perspective for patients with TNBC and this combination can quickly be offered to clinicians
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Birembaux, Olivier. "Actions de groupes résolubles scindement de f-fibres hermitiens." Valenciennes, 1997. https://ged.uphf.fr/nuxeo/site/esupversions/b7bd7233-5e92-4465-8cce-ff9ef4078593.

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Première partie : Soient G un groupe de Lie connexe de dimension n - 1, f une action localement libre de classe Cr (avec r supérieure ou égale à 2) de G sur une variété compacte M de dimension n supérieure ou égale a 3. Nous supposons qu'il existe dans l'algèbre de Lie de G un champ Y tel que la partie réelle de chaque valeur propre de ad(Y) soit strictement plus petite que 0. Alors, nous montrons que f est Cr -conjuguée à une action modèle de G sur un espace homogène H/T ou H est un groupe de Lie contenant G. Nos hypothèses impliquent que G a une structure particulière, mais il existe quand même de nombreux exemples : Notamment, la famille des groupes G ayant cette propriété est continue en toute dimension plus grande que 4 ; pour un choix générique de G, le groupe H correspondant n'a aucun quotient compact de dimension n, et ceci fournit une famille continue de groupes de Lie ne possédant aucune action de codimension 1 suffisamment régulière sur une variété compacte. Ces résultats sont liés à la théorie d'Anosov. Deuxième partie : Soient M une variété C connexe, munie d'un flot F et E un F-fibré hermitien au-dessus de M. On donne une version basique du théorème de Leray-Hirsch pour le fibré P(E), projectifié de E. Ensuite on établit un « principe de scindement » feuilleté, i. E on montre qu'il existe une variété B munie d'un flot V et une application feuilletée σ : B vers M telles que le fibré vectoriel image réciproque σ -1 E se décompose en somme directe de V-fibrés hermitiens Si de rang 1 et l'application σ*, induite en cohomologie basique, est injective.
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Books on the topic "Système de triple de Lie"

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ʻAbd Allāh ibn ʻAbbār ʻAnazī. Aṣdaq al-dalāʾil fī ansāb Banī Wāʾil: Qabāʾil ʻAnazah. 2nd ed. [al-Riyaḍ]: ʻA.A.b.ʻA. al-Maʻnī, 1991.

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Wenyu, Wang John, ed. Statistical methods for survival data analysis. 3rd ed. New York: J. Wiley, 2003.

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V, Kabanov Alexander, Felgner Philip L. 1950-, and Seymour L. W, eds. Self-assembling complexes for gene delivery: From laboratory to clinical trial. Chichester: Wiley, 1998.

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Conference on Hopf Algebras and Tensor Categories (2011 University of Almeria). Hopf algebras and tensor categories: International conference, July 4-8, 2011, University of Almería, Almería, Spain. Edited by Andruskiewitsch Nicolás 1958-, Cuadra Juan 1975-, and Torrecillas B. (Blas) 1958-. Providence, Rhode Island: American Mathematical Society, 2013.

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Jordan Triple Systems in Complex and Functional Analysis. American Mathematical Society, 2020.

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Cullen, Christopher. The Triple Concordance system and Liu Xin’s ‘Grand Unified Theory’. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198733119.003.0005.

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In 9 CE, the powerful courtier Wang Mang deposed the infant prince of Han and took power as first emperor of his own dynasty. To help him sustain this claim, Liu Xin created what amounted to a Grand Unified Theory, in which all the important regularities of nature were explained with reference to numbers. We shall look in detail at the Triple Concordance system that resulted from this initiative, and follow through some examples of calculation based on it. Here we shall meet for the first time certain common features of all such systems. Liu Xin also undertook an ambitious project to use his new system to reconstruct the records of astronomical phenomena in a number of historical texts. Liu Xin’s work gives us an in-depth view of how one of the central figures in the early development of Chinese mathematical sciences saw the world.
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Jepsen, Lance. Internet Marketing-Profits That Lie Hidden in Your Website: How to Triple Your Web Sales in 25 Days. Outskirts Press, Incorporated, 2008.

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N. M, Gayathri, and Nidhi R. THE LAW RELATING TO CLINICAL TRIALS IN INDIA: THE PREVAILING DEFICIENCIES AND THE ROAD AHEAD. Jupiter Publications Consortium, 2023. http://dx.doi.org/10.47715/jpc.b.978-93-91303-78-5.

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Clinical trials stand at the crux of medical advancement, serving as the vital link between laboratory research and the availability of new treatments for patients’ ailments. In a world increasingly reliant on evidence-based medicine, the importance of rigorous, ethical, and well-regulated clinical trials cannot be overstated. However, the dynamic and multifaceted nature of clinical trials raises complex legal, ethical, and social issues, particularly in a diverse and populous nation like India. This book, “The Law Relating to Clinical Trials in India: The Prevailing Deficiencies and the Road Ahead,” by Ms. Gayathri N. M. and Ms. Nidhi R, provides a comprehensive analysis of India’s legal framework governing clinical trials. It assesses the current state of the law, identifies the deficiencies therein, and offers a thought-provoking exploration of the path to rectifying these shortcomings. The pages within unfold the historical tapestry of clinical trials, setting the stage with an exploration of their evolution both globally and within the Indian context. The book ventures into the intricate lattice of regulations and guidelines that govern clinical trials in India and juxtaposes them against the global standards set by more developed frameworks in the United States and Canada. Through the chapters, the reader is invited to examine the role of Indian courts in interpreting and applying the laws concerning clinical trials, often acting as bulwarks against unethical practices. The narrative further delves into the comparisons between regulatory systems, thereby drawing lessons from international best practices. Perhaps most critically, this work does not shy away from discussing the challenges and deficiencies that mar the current Indian clinical trial landscape. It ventures into the depths of the 2019 New Drugs and Clinical Trials Rules (NDCTR), unearthing its flaws and potential. The Covid-19 pandemic and the resultant vaccine fast approvals present a case study, highlighting the urgency for reform in the face of unprecedented global health challenges. As we reach the denouement in the concluding chapter, the authors synthesize their findings and articulate a series of well-reasoned suggestions. Their vision for the future of India’s clinical trial legal system is one of pragmatism and hope, guided by the twin stars of participant safety and scientific integrity. The preface serves as an invitation to readers — scholars, practitioners, policymakers, and anyone with an interest in the crossroads of law, medicine, and ethics — to embark on this intellectual journey. The goal is not only to inform but also to inspire action that will shape a more robust, just, and effective framework for clinical trials in India. In closing, this book aims to contribute meaningfully to the discourse on improving the regulatory environment for clinical trials in India, ensuring that the nation’s laws keep pace with scientific progress while safeguarding the rights and welfare of participants.
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Hafemeister, Thomas. Criminal Trials and Mental Disorders. NYU Press, 2019. http://dx.doi.org/10.18574/nyu/9781479804856.001.0001.

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The American criminal justice system is based on the bedrock principles of fairness and justice for all. In striving to ensure that all criminal defendants are treated equally under the law, it endeavors to handle like-cases in like-fashion, adhering to the proposition that the same rules and procedures should be employed regardless of a defendant’s wealth or poverty, social status, race, ethnicity, or gender. Yet, exceptions have been recognized when special circumstances are perceived to have driven a defendant’s behavior or are likely to skew the defendant’s trial. Examples include the right to act in self-defense and to be appointed an attorney if you cannot afford one. Another set of exceptions, but ones that are much more controversial, poorly articulated, and inconsistently applied, involves criminal defendants with a mental disorder. Some of these individuals are perceived to be less culpable, as well as less capable of exercising the rights all defendants retain within the justice system, more in need of mental health services than criminal prosecution, and warranting enhanced protections at trial. As a result, special rules and procedures have evolved over the centuries, often without fanfare and even today with little systematic examination, to be applied to cases involving defendants with a mental disorder. This book offers that systematic examination. It identifies the various stages of criminal justice proceedings when the mental status of a criminal defendant may be relevant, associated legal and policy issues, the history and evolution of these issues, how they are currently resolved, and how forensic mental health assessments are conducted and employed during criminal proceedings.
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Groscup, Jennifer L. The Impact of Legally Relevant Media Exposure on Criminal Juror Decision-Making. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190658113.003.0007.

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Exposure to various forms of media can potentially impact decision-making by jurors in criminal trials. Cases like the highly publicized Casey Anthony trial, in which jurors’ media exposure might have affected the verdict, highlight the importance of understanding what messages jurors receive from the media and how those messages might influence their perceptions of trial participants and evidence. This chapter first explores research on the content of legally relevant news media, reality television, and scripted television dramas to better understand the messages the media might be delivering. Next, it reviews research suggesting how various media sources influence the development of legally relevant attitudes and, in turn, juror decision-making. The chapter then investigates the media’s direct influence on juror decision-making, focusing particularly on the CSI Effect. Finally, it discusses recommendations for jury system reform that might decrease media influence as well as future research directions.
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Book chapters on the topic "Système de triple de Lie"

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Jacobson, Nathan. "Lie and Jordan Triple Systems." In Nathan Jacobson Collected Mathematical Papers, 17–38. Boston, MA: Birkhäuser Boston, 1989. http://dx.doi.org/10.1007/978-1-4612-3694-8_2.

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Kamiya, Noriaki. "On Radicals of Triple Systems." In Groups, Rings, Lie and Hopf Algebras, 75–83. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4613-0235-3_5.

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Roos, Guy. "Volume of Bounded Symmetric Domains and Compactification of Jordan Triple Systems." In Lie Groups and Lie Algebras, 249–59. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5258-7_16.

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Baklouti, Amir, and Samiha Hidri. "Inductive Description of Quadratic Lie and Pseudo-Euclidean Jordan Triple Systems." In Forum for Interdisciplinary Mathematics, 65–93. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8498-5_4.

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Ashraf, Mohammad, Mohammad Afajal Ansari, and Md Shamim Akhter. "Non-global Multiplicative Lie Triple Derivations on Rings." In Springer Proceedings in Mathematics & Statistics, 207–22. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-50795-3_15.

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Ashraf, Mohammad, Mohammad Afajal Ansari, and Md Shamim Akhter. "Generalized Lie Triple Derivations of Trivial Extension Algebras." In Applied Linear Algebra, Probability and Statistics, 461–72. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-2310-6_23.

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Zhao, Jing, Hailing Li, and Lijing Fang. "Lie Triple Derivations for the Parabolic Subalgebras of gl(n,R)." In Lecture Notes in Computer Science, 457–64. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21524-7_56.

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Jiang, Hua, Peisheng Ji, and Xiaolu Sun. "Additivity of Lie Triple Isomorphisms on Standard Operator Subalgebras of Nest Algebras." In Lecture Notes in Electrical Engineering, 139–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27323-0_18.

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Savatovsky, Dan, and Thị Kiều Ly Phạm. "Maurice Grammont et la musique du cochinchinois : les débuts de la tonétique expérimentale." In Documenter et décrire les langues d’Asie : histoire et épistémologie, 137–64. Paris: Société d’histoire et d’épistémologie des sciences du langage, 2025. https://doi.org/10.4000/138nc.

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Cet article est consacré à deux écrits du linguiste Maurice Grammont : i) les Recherches expérimentales sur la prononciation du cochinchinois (1910-11) – menées dans le cadre du laboratoire fondé par Grammont à Montpellier – portant principalement sur le système tonal d’une variété dialectale du vietnamien, qui est décrit grâce aux instruments de la phonétique expérimentale. Ces Recherches… figurent parmi les tout premiers travaux en tonétique réalisés par un linguiste professionnel ; ii) les Études sur la langue annamite (1912), cosignées par Lê Quang Trình, de type à la fois phonétique, « morphologique » (portant sur la composition lexicale), syntaxique et sémantique. Leur examen s’inscrit dans une triple perspective : dans leur horizon de rétrospection, on souligne leur originalité par rapport aux descriptions antérieures du vietnamien en montrant qu’ils échappent pour l’essentiel aux approches contrastives qui les caractérisaient toutes ; dans leur horizon de prospection, on évoque en particulier leur réception par Maspero, Vendryes, Haudricourt et Gsell ; enfin, on les met en regard d’autres travaux phonétiques de Grammont. On s’attache dans ce cadre à l’analyse de la dissimilation vocalique et surtout des tons du vietnamien en insistant notamment sur deux aspects : la combinaison « note » (hauteur)/timbre et les particularités phonétiques du parler « cochinchinois » (à cinq tons) vs la langue standard « tonkinoise » (à six tons).
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Caro-González, A., A. Serra, X. Albala, C. E. Borges, D. Casado-Mansilla, J. Colobrans, E. Iñigo, J. Millard, A. Mugarra-Elorriaga, and Renata Petrevska Nechkoska. "The Three MuskEUteers." In Contributions to Management Science, 3–28. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-11065-8_1.

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AbstractUnder the inspiring and aspiring title: Paving the way for pushing and pursuing a “one for all, all for one” triple transition: social, green, and digital: The Three MuskEUteers, a group of remarkable co-authors and contributors have developed radically new forward-looking visions, principles, approaches, and action recommendations for an attuned indivisible social, green, and digital transition.The triple transition is aimed at helping humanity gather around a life-sustaining purpose, as opposed to life-destroying one in terms of wars of all kinds (military, economic, political, etc.); nature decay and wreckage (carbon footprint, plastic pollution, soil poisoning, etc.); human alienation (favelas, homeless persons, refugee camps, child malnutrition, poverty, exclusion of any kind); and geographic imbalances with empty rural spaces and overcrowded megacities (creating difficult access of rural and/or remote population to care, health, and other essential services; difficulty of urban population to contact with natural environments).The work highlights the urgent need to speed up a third social transition (Within this social transition dimension we understand the socio-cultural scope as any social shift implies a cultural transition and vice versa, with its very deep implications.), in addition to the green and digital transitions more widely recognised by the international community. Innovation, or a European industry-led twin transition aiming for climate neutrality and digital leadership, cannot be supported without a firm, responsive, responsible social and environmental engagement. Neither is it possible to tackle a JUST triple transition which is not firmly rooted in worthwhile human development, underpinned by the Sustainable Development Goals. And none of these transitions can go separately and/or isolated; they all need to intertwine around the notion of (more, firmer, and determined) just transition.European society is presented as a huge “co-laboratory” for this “all for one, one for all” boundaryless triple transition to respond to the urgent radical changes demanded by humanity and by the planet. The chapter proposes a radically new vision to pursue a non-explored transformative way to ideate, design, develop, and deliver science, innovation, and collaboration through experimentation and learning, and throughout multi-stakeholder engagement from the n-helix spectrum. It proposes systemic innovation tactics for the “how” (green, techno-digital), for the strategic “what” (green, social), for the purposeful “why” (green, social), and for the operational “how best” (green, social, techno-digital) within the governing principles of eco-centric society. This encompasses: Courageous goal-aligned alternatives, as a shift to new (yet ancient) principles of eco-centric rather than ego-centric behaviour. The adoption of a “complex system mind-set” to build up dynamic, context-sensitive, and holistic approaches to co-design mission and purpose-driven actions, outcomes, outputs, and no-harm impacts. The ignition of the transformative capacity of all forms of collaboration (international, interdisciplinary, intersectoral, intergenerational, inter-institutional, inter-genders) vs hierarchy as alternative governance and distribution models to overcome the unjust and unsustainable biased status quo within evolving, adaptable, flexible, and transformational n-helix ecosystems. The Three MuskEUteers, deeply anchored in European values (human dignity, freedom, democracy, equality, rule of law, and human rights), will pave the way and drive humanity towards the achievement of the ambitious, but achievable, targets of the United Nations 2030 Global Agenda, the Sustainable Development Goals.Europe can be the initiator of co-laboratory experiments where social change drives the “all for one, one for all” dream into transforming this three-prong transition into possible real good ecosystems working.
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Conference papers on the topic "Système de triple de Lie"

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Bashenini, M. S., B. M. Bhandari, and K. G. Davies. "Trials of Corrosion Control Procedures for Underground Reinforced Concrete Power Manholes." In CORROSION 1989, 1–19. NACE International, 1989. https://doi.org/10.5006/c1989-89389.

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Abstract Severe chloride-ion-induced corrosion damage has occurred on some of the 2500 underground reinforced concrete power manholes at Jubail Industrial City. These manholes carry 34.5 - 115kV cables and are part of the electrical power distribution network. They are approximately 6 years old, have an internal dimension of up to 8 m and are as much as 6 m below the groundwater table. A survey has shown that some 150 manholes needed urgent attention to prevent further structural damage that might affect the power distribution system on which the City depends. Numerous options for rehabilitating the manholes were considered and evaluated and finally two methods were chosen. For shallow manholes, not congested with cables, a new manhole would be constructed within the existing one. For deep manholes, or those congested with cables, all unsound concrete would be properly repaired and an impressed current cathodic protection (ICCP) system installed. The latter method - concrete repair and the design and installation of a cathodic protection system - had to consider the existing installations, restricted access, remoteness of some manholes, and the presence of high-voltage cables, which had to stay energized during repair work. Furthermore, the repair and protection had to be dependable and maintainable during the design life. The conventional application of cementitious overlays, such as shotcrete, could not be used, so demonstration trials were carried out to examine the constructibility, performance and suitability of alternative overlays and ICCP systems.
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Jansen, H. J. M., N. I. S. Al-Behlani, and H. A. H. Qamshoey. "Application of Non-Metallic Line Pipe Materials to Reduce Life Cycle Cost of Upstream Oil & Gas Gathering Production Facilities." In CORROSION 2005, 1–13. NACE International, 2005. https://doi.org/10.5006/c2005-05527.

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Abstract In 2003, the Company in Oman, produced 700,000 bbl/day net oil and 4,000,000 bbl/day water from a large number of widely geographically spread mature fields. The produced fluids in the gathering system are becoming more aggressive resulting in high corrosion rates of carbon steel flowlines. In order to manage flowline corrosion, the Company has long had the leading edge in the Arabian Gulf Region in the application of a range of non-metallic pipe materials. Glass Reinforced Epoxy (GRE) pipe and polyethylene (PE) liners are widely applied and products such as reelable Reinforced Thermoplastic Pipe (RTP) and spoolable GRE have been developed, qualified, trialed and are now being applied. This paper describes the operating envelopes as applied by the Company of the various materials used and discusses the minimum life-cycle cost based materials selection strategy developed by the Company for the gathering systems.
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Decker, Lance N., Jerry Knoblach, and J. Craig Kitchin. "Trials and Experiences in Wireless Automated Pipeline Rectifier Monitoring." In CORROSION 2008, 1–10. NACE International, 2008. https://doi.org/10.5006/c2008-08061.

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Abstract Remote equipment, challenging terrain, long runs of power services, government regulation, and manpower costs create an environment for wireless automated pipeline rectifier monitoring. This paper will discuss the trials, experiences, lessons and real life application of low cost, broad area, wireless cathodic protection (CP) rectifier monitoring for remote areas. The system goals are to monitor the CP equipment status, retrieve and report the rectifier output daily, report anomalies as they occur (power outages, drastic changes in rectifier output, etc.), create DOT reports (or interface with current reporting mechanisms), and give a graphical display of the rectifier behavior over time.
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Lyublinski, Efim, Kelly Baker, Terry Natale, Monique Posner, Gautam Ramdas, Alexander Roytman, Yefim Vaks, and Marcelo Schultz. "Corrosion Protection of Storage Tank Soil Side Bottoms Application Experience." In CORROSION 2015, 1–5. NACE International, 2015. https://doi.org/10.5006/c2015-06016.

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Abstract Corrosion of soil side bottoms is unpredictable and can be up to 5 mm/year. The soil side bottom cannot be protected while the tank is in service. The well-known cathodic protection system is not efficient enough. This paper presents case studies of soil side bottom corrosion protection using new systems with volatile and soluble corrosion inhibitors installed on new and existing soil side and double bottom aboveground storage tanks. This paper describes field trial and application experience of principally new corrosion protection systems for different designs of storage tank foundations. The new system demonstrates corrosion protection efficiencies as high as 70-90% and also decreases the incidence of pitting corrosion in most aggressive environment conditions. Application experience has shown that inhibitor use can increase the tank service life approximately 3-5 times and reduce maintenance and replacement costs.
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Martinussen, Hanne, Ingar Stian Nerbø, Harald Sleire, Ole Alexander Eek, and Trine Okstad. "Observation of the Flow Dependent Corrosion Rate by Ultrasound Corrosion Monitoring on a Gas Pipeline." In CORROSION 2017, 1–11. NACE International, 2017. https://doi.org/10.5006/c2017-09336.

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Abstract An ultrasonic erosion and corrosion monitoring system which provides real-time, online wall thickness data for onshore and topside piping and pipelines is presented. It is non-invasive and is installed and operated without interfering with production. Pulse-echo ultrasound monitoring provides fast and accurate data concerning erosion and corrosion rates, making it an effective tool for feedback in corrosion inhibitor programs. A 6-month trial of the ultrasonic monitoring system has been performed on an 8 inch OD water pipe in a gas plant. The system recorded measurements 4 times per day. In addition, manual ultrasonic testing (UT) was performed before and after the trial period. Comparison of the results showed that the manual UT measurements overestimated the corrosion rates by more than 100% compared to the ultrasonic monitoring system. During the trial period, a significant increase in the corrosion rate was observed. The increased corrosion was correlated to an increase in the flow rate in the same time period. This trial demonstrated that ultrasonic monitoring can be applied to detect changes in real-life corrosion rates in a short time (3 weeks). This short feedback time can be used to give advanced warnings on corrosion issues on bends, T-pieces or other areas. Using the ultrasonic corrosion monitoring system the operator will obtain a more accurate lifetime estimate of the pipe, and the possibility to plan for an accurate maintenance program.
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Binder, G. J. "Determine Usable Coating Systems - Results of Laboratory Tests versus Long Term Trials in Nature." In CORROSION 2008, 1–14. NACE International, 2008. https://doi.org/10.5006/c2008-08001.

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Abstract Accelerated laboratory tests are commonly used for judging the performance of coatings for corrosion protection. Assessment could be done by comparison of systems or measuring the damages after the test, mainly the rusting on the scratch, and checked against fixed boundary values. In this study common test methods like salt spray (ISO 7253), as well as cyclic test (NORSOK M-501, ISO 20340) were checked and compared to each other by statistical calculations. By that any relationship between the different tests were figured out. The cycle test according ISO 20340 for offshore structures is relatively new and experiences in practice are limited. Immediately the test procedure indicates that results using this method that only systems with zinc-dust primers passed the test and many well established coating systems failed. The statistical calculations in this work showed, that the test procedure can be shortened by nearly a factor of two to reach comparable results to other accelerated tests and by that time and money will be saved. Results of cycle tests also were compared with test results of long term trials in nature (e.g. immersion and water changing in northern sea). By that procedure acceleration factors of laboratory test were considered. Beneath these tests of rusting of surface further important test parameters for improving the protection behaviour of coating systems under offshore conditions are described in this work.
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Call, Ted. "Thermal Spray Coatings - past, Present & Future." In SSPC 2005, 1–6. SSPC, 2005. https://doi.org/10.5006/s2005-00007.

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Abstract Thermal spray coatings (TSC) have been successfully used in all major sectors of the marine and industrial corrosion control coatings market. Approximately twenty years ago they were introduced to the bridge coatings sector of the market on a trial basis. The overall positive results of these TSC tests in the bridge market have generated a wealth of information and much is known today about their origin and benefits. TSC have proven to be the longest lasting coating systems available. They are the most cost effective from a life cycle cost (LCC) analysis and their initial application cost is continuing to drop (1). This paper will discuss the present status of TSC as an approved alternative coating system and what needs to be done in order to effectively promote their use as a viable mainstream coating system to benefit the future bridge coatings market.
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McGough, C. M., P. H. Gill, and R. A. Muia. "Lessons Learned in over 100 Zebra Mussel Control Applications at Industrial Facilities." In CORROSION 1998, 1–11. NACE International, 1998. https://doi.org/10.5006/c1998-98524.

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Abstract Since their introduction into US waterways, Zebra Mussels (Dreissena polymorphae) have spread rapidly throughout the Great Lakes and Mississippi regions. These mussels have continued to colonize the intake pipes of industrial water supplies and water distribution systems throughout the affected areas. Their colonization has compromised plant safety and production efficiency, and steadily increased costs to water users. The design of each industrial plant water distribution system is unique. A comprehensive zebra mussel control strategy using the best available options must be considered in each specific situation. This paper discusses the successful use of one strategy (a quaternary ammonia-based molluscicide) in the battle against zebra mussels. The commercial life cycle of an industrial molluscicide began with initial toxicity screening in the laboratory. The evaluation continued at plant sites through field trials and applications. Lessons learned from these experiences helped direct our efforts toward the development of a second generation program.
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Bazzoni, Bruno, Simone Pietro Dubini, Filippo Belloni, Ahmed Msallem, Paolo Cavassi, and Isabella Romeo. "Bouri Field Platforms, Libya. Review and Statistical Analysis of Cathodic Protection Inspection Data." In CORROSION 2011, 1–18. NACE International, 2011. https://doi.org/10.5006/c2011-11051.

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Abstract Bouri Field is located in the Mediterranean Sea, about 120 km North West of Tripoli – in waters 160-170 m deep. The field includes the following main assets: drilling-production platforms (two); inter-field pipeline; sub-sea wells; FSO. The two platforms are the biggest ones in the Mediterranean Sea. Submerged structures are protected against seawater corrosion by means of aluminum alloy galvanic anodes. The original design life of the cathodic protection system was 35 years; however the Bouri CP System Performance Study has indicated that the expected life span of the CP system can be extended by 15 years. During the past operating life, a number of Underwater Inspection Campaigns have been carried out and a significant amount of data has been collected over a period of more than 20 years. These data, in particular structure potentials and anode consumptions, have been gathered and reviewed. The analysis included: follow up of the structure polarization; assessment of the actual protection current density demand; comparisons with the requirements of the international normative. Furthermore, a statistical analysis has been applied to the whole set of data. The paper illustrates the main evidences from data review, the adopted statistical approach and results of the statistical analysis.
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Baynham, John MW, Tim Froome, and Robert A. Adey. "Jacket SACP System Design and Optimization Using Simulation." In CORROSION 2012, 1–19. NACE International, 2012. https://doi.org/10.5006/c2012-01281.

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Abstract Design of sacrificial anode cathodic protection (SACP) systems to achieve uniform anode mass loss rates is desirable, since it helps avoid early installation of costly retrofit systems which may be needed if some anodes are consumed more quickly than others. Such optimized design is only practically possible through the use of mathematical modeling performed using numerical techniques. A range of numerical methodologies can be applied to simulation of galvanic effects and cathodic protection, and of these it is the boundary element method that is applied in this work. The simulation requires an accurate model of the structure which is to be protected, as well as the anodes, and any other metallic structures which may act as current drains even though they may not need to be cathodically protected). The optimization process first involves design and simulation of an initial SACP system design. Performance of the design is assessed against criteria which may include anode mass loss rate, most positive allowed potential and remaining anode mass, not only at start of life, but also throughout the design life of the structure. The results of previous assessments are used to guide the selection of the next trial SACP system design, which usually involves changing the number, position or size of anodes, while adhering to user-defined rules (e. g. “keep-out areas”). The process is repeated until satisfactory results are obtained. The objective of this paper is to explore such simulation techniques, and show how they can be combined to provide a practical toolset for SACP system design optimization. This provides the user with new and significantly more powerful design capabilities which are based on real physics rather than standardized design rules. The use of these tools both reduces the risk of the CP design not meeting its required life and ensures an economical design The paper illustrates performance of the design and optimization processes using a jacket structure for which long-term “sigmoidal” polarization curves provide an appropriate representation of calcareous deposits.
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Reports on the topic "Système de triple de Lie"

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Tiku, Sanjay, Arnav Rana, Binoy John, and Aaron Dinovitzer. PR-214-203805-R01 Performance Evaluation of ILI Systems for Dents and Coincident Features. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), March 2024. http://dx.doi.org/10.55274/r0000056.

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Pipeline integrity management involves the analysis of pipeline condition information (e.g., pipe size, presence and size of features), operational/environmental conditions and line pipe material properties in engineering assessment (fitness-for-purpose) tools to evaluate operational risk. While nominal or minimum specified material properties and SCADA reported, design or estimated operational loading conditions can be considered, pipeline operators depend heavily on pipeline condition data from in-line inspection (ILI) systems. The current project presents the details of performance trials evaluating the ability of ILI systems to provide pipeline condition information for dents with coincident or closely aligned features. A set of sample dent features were prepared along with a trial protocol and performance metrics beyond those presented in API 1163 that were used to characterize performance. ILI system pull and pump through trials of magnetic, ultrasonic and caliper-based ILI technologies from four ILI Service Providers were performed. Data from these trials were used to quantify detection, identification, and sizing performance of the ILI systems for isolated corrosion features, dents with variety of shapes including those without coincident features and those with corrosion, gouges and/or cracks. The effect of dents on the ILI system detection, identification and sizing of the coincident features was evaluated.
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Tiku, Sanjay. PR-214-203820-R01 Performance Evaluation of ILI for Dents with Cracks and Gouges. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2023. http://dx.doi.org/10.55274/r0000031.

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Pipeline integrity management involves the analysis of pipeline condition information (e.g., pipe size, presence and size of features), operational/environmental conditions and line pipe material properties in engineering assessment (fitness-for-purpose) tools to evaluate operational risk. While nominal or minimum specified material properties and SCADA reported, design or estimated operational loading conditions can be considered, pipeline operators depend heavily on pipeline condition data from in-line inspection (ILI) systems. The current project presents the details of performance trials evaluating the ability of ILI systems to provide pipeline condition information for dents with coincident or closely aligned features. A set of sample dent features were prepared along with a trial protocol and performance metrics beyond those presented in API 1163 that were used to characterize performance. ILI system pull and pump through trials of magnetic, ultrasonic and caliper-based ILI technologies from seven ILI Service Providers were performed. Data from these trials were used to quantify detection, identification, and sizing performance of the ILI systems for isolated corrosion features, dents with variety of shapes including those without coincident features and those with corrosion, gouges and/or cracks. The effect of dents on the ILI system detection, identification and sizing of the coincident features was evaluated.
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Garceau, Sean. PR-283-20207-R01 Field Trial of Solar Turbines Methane Emissions Reduction Solution for Gas Compressors. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2022. http://dx.doi.org/10.55274/r0012230.

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The Methane Emissions Reduction solution designed by Solar Turbines was installed and evaluated at the Berkshire Hathaway Energy (Dominion) Chambersburg station in Pennsylvania, USA. Solar Turbines supplied a dry seal recompression (DSR) system and a process vent recompression (PVR) system at the station. The objective of the field trial was to evaluate the durability of this new system, compare the performance in the field to simulation models and as needed make improvements to the mechanical design and/or software control. The dry gas seal recompression system was installed and connected to a Solar Turbines C402 process compressor dry seal primary vent to capture, hold, and reuse dry seal gas leakage. The process vent recompression system was connected to the C402 compressor discharge piping to capture the process gas during pressurized hold and inject it back into the suction line in lieu of venting the gas to atmosphere. Operational data for the two systems was collected for 22-months starting in January 2020 and ending in October 2021. Data was collected at different sample rates; high speed (10ms, 100ms), 1 second, 10 seconds, and 1 hour through historical logs and analyzed for this period of time to evaluate the durability of the systems. Several enhancements were implemented and validated. Data collected during a 12-month period showed that a recycle line and volume bottles on the suction of the compressor helped optimize the performance of the compressor and increased durability. In addition, the use of the auxiliary drain recapture tank on the DSR system allowed for the achievement of a capture rate greater than 99% and resolved issues associated with leakage back into the compressor's first stage inlet during the charge period of the cycle.
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You, Siming, Ondřej Mašek, Bauyrzhan Biakhmetov, Simon Ascher, Sudeshna Lahiri, PreetiChaturvedi Bhargava, Thallada Bhaskar, Supravat Sarangi, and Sunita Varjani. Feasibility and impacts of Bioenergy Trigeneration systems (BioTrig) in disadvantaged rural areas in India. University of Glasgow, August 2023. http://dx.doi.org/10.36399/gla.pubs.305660.

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This project aims to evaluate the techno-economic and social feasibility, and socio-environmental impacts of bioenergy trigeneration (electricity, clean cooking fuel, and green soil conditioner) systems that tackle the triple crisis of poor electrification, household air pollution, and farmland contamination in rural India. This system is called BioTrig. A project workshop has been held in November in India to discuss and finalise action plans. A questionnaire has been developed to understand the energy, resource, and new technology acceptance of rural households in India. Chemical process modelling, life cycle assessment and cost-benefit analysis has been conducted to evaluate the environmental impact and economic feasibility of BioTrig.
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Lewis, Sherman, Emilio Grande, and Ralph Robinson. The Mismeasurement of Mobility for Walkable Neighborhoods. Mineta Transportation Institute, November 2020. http://dx.doi.org/10.31979/mti.2020.2060.

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The major US household travel surveys do not ask the right questions to understand mobility in Walkable Neighborhoods. Yet few subjects can be more important for sustainability and real economic growth based on all things of value, including sustainability, affordability, and quality of life. Walkable Neighborhoods are a system of land use, transportation, and transportation pricing. They are areas with attractive walking distances of residential and local business land uses of sufficient density to support enough business and transit, with mobility comparable to suburbia and without owning an auto. Mobility is defined as the travel time typically spent to reach destinations outside the home, not trips among other destinations that are not related to the home base. A home round trip returns home the same day, a way of defining routine trips based on the home location. Trip times and purposes, taken together, constitute travel time budgets and add up to total travel time in the course of a day. Furthermore, for Walkable Neighborhoods, the analysis focuses on the trips most important for daily mobility. Mismeasurement consists of including trips that are not real trips to destinations outside the home, totaling 48 percent of trips. It includes purposes that are not short trips functional for walk times and mixing of different trips into single purposes, resulting in even less useful data. The surveys do not separate home round trips from other major trip types such as work round trips and overnight trips. The major household surveys collect vast amounts of information without insight into the data needed for neighborhood sustainability. The methodology of statistics gets in the way of using statistics for the deeper insights we need. Household travel surveys need to be reframed to provide the information needed to understand and improve Walkable Neighborhoods. This research makes progress on the issue, but mismeasurement prevents a better understanding of the issue.
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Einarsson, Rasmus. Nitrogen in the food system. TABLE, February 2024. http://dx.doi.org/10.56661/2fa45626.

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Nitrogen (N) plays a dual role in the agri-food system: it is an essential nutrient for all life forms, yet also an environmental pollutant causing a range of environmental and human health impacts. As the plant nutrient needed in greatest quantities, and as a building block of proteins and other biomolecules, N is a necessary part of all life. In the last century, an enormous increase of N turnover in the agri-food system has enabled increasing per-capita food supply for a growing world population, but as an unintended side effect, N pollution has increased to levels widely agreed in science and policy to be far beyond sustainable limits. There is no such thing as perfectly circular N supply. Losses of N to the environment inevitably arise as N is transformed and used in the food system, for example in soil processes, in manure storage, and in fertilizer application. This lost N must be replaced by ‘new’ N, which is N converted to bioavailable forms from the vast atmospheric pool of unreactive dinitrogen (N2). New N comes mainly as synthetic N fertilizer and through a process known as biological N fixation (BNF). In addition, there is a large internal flow of recycled N in the food system, mainly in the form of livestock excreta. This recirculated N, however, is internal to the food system and cannot make up for the inevitable losses of N. The introduction of synthetic N fertilizer during the 20th century revolutionized the entire food system. The industrial production of synthetic N fertilizer was a revolution for agricultural systems because it removed the natural constraint of N scarcity. Given sufficient energy, synthetic N fertilizer can be produced in limitless quantities from atmospheric dinitrogen (N2). This has far-reaching consequences for the whole agri-food system. The annual input of synthetic N fertilizer today is more than twice the annual input of new N in pre-industrial agriculture. Since 1961, increased N input has enabled global output of both crop and livestock products to roughly triple. During the same time period, total food-system N emissions to the environment have also more than tripled. Livestock production is responsible for a large majority of agricultural N emissions. Livestock consume about three-quarters of global cropland N output and are thereby responsible for a similar share of cropland N emissions to air and water. In addition, N emissions from livestock housing and manure management systems contribute a substantial share of global N emissions to air. There is broad political agreement that global N emissions from agriculture should be reduced by about 50%. High-level policy targets of the EU and of the UN Convention on Biological Diversity are for a 50% reduction in N emissions. These targets are in line with a large body of research assessing what would be needed to stay within acceptable limits as regards ecosystem change and human health impacts. In the absence of dietary change towards less N-intensive diets, N emissions from food systems could be reduced by about 30%, compared to business-as-usual scenarios. This could be achieved by implementing a combination of technical measures, improved management practices, improved recycling of wasted N (including N from human excreta), and spatial optimization of agriculture. Human dietary change, especially in the most affluent countries, offers a huge potential for reducing N emissions from food systems. While many of the world’s poor would benefit nutritionally from increasing their consumption of nutrient-rich animal-source foods, many other people consume far more nutrients than is necessary and could reduce consumption of animal-source food by half without any nutritional issues. Research shows that global adoption of healthy but less N-polluting diets might plausibly cut future food-system N losses by 10–40% compared to business-as-usual scenarios. There is no single solution for solving the N challenge. Research shows that efficiency improvements and food waste reductions will almost certainly be insufficient to reach agreed environmental targets. To reach agreed targets, it seems necessary to also shift global average food consumption onto a trajectory with less animal-source food.
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John A. Sinsel. Plant Line Trial Evaluation of Viable Non-Chromium Passivation Systems for Electrolytin Tinplate, ETP (TRP 9911). Office of Scientific and Technical Information (OSTI), June 2003. http://dx.doi.org/10.2172/840952.

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Sartain, Bradley, Kurt Getsinger, Damian Walter, John Madsen, and Shayne Levoy. Flowering rush control in hydrodynamic systems : part 1 : water exchange processes. Engineer Research and Development Center (U.S.), September 2022. http://dx.doi.org/10.21079/11681/45425.

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In 2018, field trials evaluated water-exchange processes using rhodamine WT dye to provide guidance on the effective management of flowering rush (Butomus umbellatus L.) at McNary Dam and Reservoir (Wallula Lake, 15,700 ha). Additional evaluations determined the effectiveness of BubbleTubing (hereafter referred to as bubble curtain) at reducing water exchange within potential flowering rush treatment areas. Dye readings were collected from multiple sampling points at specific time intervals until a dye half-life could be determined. Whole-plot dye half-lives at sites without bubble curtain ranged 0.56–6.7 h. In slower water-exchange sites (≥2.6 h dye half-life), the herbicide diquat should have a sufficient contact time to significantly reduce flowering rush aboveground biomass. Other sites demonstrated very rapid water exchange (<1.5 h dye half-life), likely too rapid to effectively control flowering rush using chemical treatments without the use of a barrier or curtain to slow water exchange. At one site, the use of the bubble curtain increased the dye half-life from 3.8 h with no curtain to 7.6 and 7.1 h with a bubble curtain. The bubble curtain’s ability to slow water exchange will provide improved chemical control and in-crease the potential for other chemical products to be effectively used.
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Virtucio, Michael, Barbaros Cetiner, Bingyu Zhao, Kenichi Soga, and Erturgul Taciroglu. A Granular Framework for Modeling the Capacity Loss and Recovery of Regional Transportation Networks under Seismic Hazards: A Case Study on the Port of Los Angeles. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, June 2024. http://dx.doi.org/10.55461/hxhg3206.

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Earthquakes, being both unpredictable and potentially destructive, pose great risks to critical infrastructure systems like transportation. It becomes crucial, therefore, to have both a fine-grained and holistic understanding of how the current state of a transportation system would fare during hypothetical hazard scenarios. This paper introduces a synthesis approach to assessing the impacts of earthquakes by coupling an image-based structure-and-site-specific bridge fragility generation methodology with regional-scale traffic simulations and economic loss prediction models. The proposed approach’s use of context-rich data such as OpenStreetMap and Google Street View enables incorporating information that is abstracted in standard loss analysis tools like HAZUS in order to construct nonlinear bridge models and corresponding fragility functions. The framework uses a semi-dynamic traffic assignment model run on a regional traffic network that includes all freeways and local roads (1,444,790 edges) and outputs traffic volume on roads before and after bridge closures due to an earthquake as well as impacts to individual trips (42,056,426 trips). The combination of these models enables granularity, facilitating a bottom-up approach to estimating costs incurred solely due to physical damage to the transportation network. As a case study, the proposed framework is applied to the road network surrounding the Port of Los Angeles---an infrastructure of crucial importance---for assessing resilience and losses at a high resolution. It is found that the port area is disproportionately impacted in the hypothetical earthquake scenario, and delays in bridge repair can lead to a 50% increase in costs.
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Rankin, Nicole, Deborah McGregor, Candice Donnelly, Bethany Van Dort, Richard De Abreu Lourenco, Anne Cust, and Emily Stone. Lung cancer screening using low-dose computed tomography for high risk populations: Investigating effectiveness and screening program implementation considerations: An Evidence Check rapid review brokered by the Sax Institute (www.saxinstitute.org.au) for the Cancer Institute NSW. The Sax Institute, October 2019. http://dx.doi.org/10.57022/clzt5093.

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Background Lung cancer is the number one cause of cancer death worldwide.(1) It is the fifth most commonly diagnosed cancer in Australia (12,741 cases diagnosed in 2018) and the leading cause of cancer death.(2) The number of years of potential life lost to lung cancer in Australia is estimated to be 58,450, similar to that of colorectal and breast cancer combined.(3) While tobacco control strategies are most effective for disease prevention in the general population, early detection via low dose computed tomography (LDCT) screening in high-risk populations is a viable option for detecting asymptomatic disease in current (13%) and former (24%) Australian smokers.(4) The purpose of this Evidence Check review is to identify and analyse existing and emerging evidence for LDCT lung cancer screening in high-risk individuals to guide future program and policy planning. Evidence Check questions This review aimed to address the following questions: 1. What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? 2. What is the evidence of potential harms from lung cancer screening for higher-risk individuals? 3. What are the main components of recent major lung cancer screening programs or trials? 4. What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Summary of methods The authors searched the peer-reviewed literature across three databases (MEDLINE, PsycINFO and Embase) for existing systematic reviews and original studies published between 1 January 2009 and 8 August 2019. Fifteen systematic reviews (of which 8 were contemporary) and 64 original publications met the inclusion criteria set across the four questions. Key findings Question 1: What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? There is sufficient evidence from systematic reviews and meta-analyses of combined (pooled) data from screening trials (of high-risk individuals) to indicate that LDCT examination is clinically effective in reducing lung cancer mortality. In 2011, the landmark National Lung Cancer Screening Trial (NLST, a large-scale randomised controlled trial [RCT] conducted in the US) reported a 20% (95% CI 6.8% – 26.7%; P=0.004) relative reduction in mortality among long-term heavy smokers over three rounds of annual screening. High-risk eligibility criteria was defined as people aged 55–74 years with a smoking history of ≥30 pack-years (years in which a smoker has consumed 20-plus cigarettes each day) and, for former smokers, ≥30 pack-years and have quit within the past 15 years.(5) All-cause mortality was reduced by 6.7% (95% CI, 1.2% – 13.6%; P=0.02). Initial data from the second landmark RCT, the NEderlands-Leuvens Longkanker Screenings ONderzoek (known as the NELSON trial), have found an even greater reduction of 26% (95% CI, 9% – 41%) in lung cancer mortality, with full trial results yet to be published.(6, 7) Pooled analyses, including several smaller-scale European LDCT screening trials insufficiently powered in their own right, collectively demonstrate a statistically significant reduction in lung cancer mortality (RR 0.82, 95% CI 0.73–0.91).(8) Despite the reduction in all-cause mortality found in the NLST, pooled analyses of seven trials found no statistically significant difference in all-cause mortality (RR 0.95, 95% CI 0.90–1.00).(8) However, cancer-specific mortality is currently the most relevant outcome in cancer screening trials. These seven trials demonstrated a significantly greater proportion of early stage cancers in LDCT groups compared with controls (RR 2.08, 95% CI 1.43–3.03). Thus, when considering results across mortality outcomes and early stage cancers diagnosed, LDCT screening is considered to be clinically effective. Question 2: What is the evidence of potential harms from lung cancer screening for higher-risk individuals? The harms of LDCT lung cancer screening include false positive tests and the consequences of unnecessary invasive follow-up procedures for conditions that are eventually diagnosed as benign. While LDCT screening leads to an increased frequency of invasive procedures, it does not result in greater mortality soon after an invasive procedure (in trial settings when compared with the control arm).(8) Overdiagnosis, exposure to radiation, psychological distress and an impact on quality of life are other known harms. Systematic review evidence indicates the benefits of LDCT screening are likely to outweigh the harms. The potential harms are likely to be reduced as refinements are made to LDCT screening protocols through: i) the application of risk predication models (e.g. the PLCOm2012), which enable a more accurate selection of the high-risk population through the use of specific criteria (beyond age and smoking history); ii) the use of nodule management algorithms (e.g. Lung-RADS, PanCan), which assist in the diagnostic evaluation of screen-detected nodules and cancers (e.g. more precise volumetric assessment of nodules); and, iii) more judicious selection of patients for invasive procedures. Recent evidence suggests a positive LDCT result may transiently increase psychological distress but does not have long-term adverse effects on psychological distress or health-related quality of life (HRQoL). With regards to smoking cessation, there is no evidence to suggest screening participation invokes a false sense of assurance in smokers, nor a reduction in motivation to quit. The NELSON and Danish trials found no difference in smoking cessation rates between LDCT screening and control groups. Higher net cessation rates, compared with general population, suggest those who participate in screening trials may already be motivated to quit. Question 3: What are the main components of recent major lung cancer screening programs or trials? There are no systematic reviews that capture the main components of recent major lung cancer screening trials and programs. We extracted evidence from original studies and clinical guidance documents and organised this into key groups to form a concise set of components for potential implementation of a national lung cancer screening program in Australia: 1. Identifying the high-risk population: recruitment, eligibility, selection and referral 2. Educating the public, people at high risk and healthcare providers; this includes creating awareness of lung cancer, the benefits and harms of LDCT screening, and shared decision-making 3. Components necessary for health services to deliver a screening program: a. Planning phase: e.g. human resources to coordinate the program, electronic data systems that integrate medical records information and link to an established national registry b. Implementation phase: e.g. human and technological resources required to conduct LDCT examinations, interpretation of reports and communication of results to participants c. Monitoring and evaluation phase: e.g. monitoring outcomes across patients, radiological reporting, compliance with established standards and a quality assurance program 4. Data reporting and research, e.g. audit and feedback to multidisciplinary teams, reporting outcomes to enhance international research into LDCT screening 5. Incorporation of smoking cessation interventions, e.g. specific programs designed for LDCT screening or referral to existing community or hospital-based services that deliver cessation interventions. Most original studies are single-institution evaluations that contain descriptive data about the processes required to establish and implement a high-risk population-based screening program. Across all studies there is a consistent message as to the challenges and complexities of establishing LDCT screening programs to attract people at high risk who will receive the greatest benefits from participation. With regards to smoking cessation, evidence from one systematic review indicates the optimal strategy for incorporating smoking cessation interventions into a LDCT screening program is unclear. There is widespread agreement that LDCT screening attendance presents a ‘teachable moment’ for cessation advice, especially among those people who receive a positive scan result. Smoking cessation is an area of significant research investment; for instance, eight US-based clinical trials are now underway that aim to address how best to design and deliver cessation programs within large-scale LDCT screening programs.(9) Question 4: What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Assessing the value or cost-effectiveness of LDCT screening involves a complex interplay of factors including data on effectiveness and costs, and institutional context. A key input is data about the effectiveness of potential and current screening programs with respect to case detection, and the likely outcomes of treating those cases sooner (in the presence of LDCT screening) as opposed to later (in the absence of LDCT screening). Evidence about the cost-effectiveness of LDCT screening programs has been summarised in two systematic reviews. We identified a further 13 studies—five modelling studies, one discrete choice experiment and seven articles—that used a variety of methods to assess cost-effectiveness. Three modelling studies indicated LDCT screening was cost-effective in the settings of the US and Europe. Two studies—one from Australia and one from New Zealand—reported LDCT screening would not be cost-effective using NLST-like protocols. We anticipate that, following the full publication of the NELSON trial, cost-effectiveness studies will likely be updated with new data that reduce uncertainty about factors that influence modelling outcomes, including the findings of indeterminate nodules. Gaps in the evidence There is a large and accessible body of evidence as to the effectiveness (Q1) and harms (Q2) of LDCT screening for lung cancer. Nevertheless, there are significant gaps in the evidence about the program components that are required to implement an effective LDCT screening program (Q3). Questions about LDCT screening acceptability and feasibility were not explicitly included in the scope. However, as the evidence is based primarily on US programs and UK pilot studies, the relevance to the local setting requires careful consideration. The Queensland Lung Cancer Screening Study provides feasibility data about clinical aspects of LDCT screening but little about program design. The International Lung Screening Trial is still in the recruitment phase and findings are not yet available for inclusion in this Evidence Check. The Australian Population Based Screening Framework was developed to “inform decision-makers on the key issues to be considered when assessing potential screening programs in Australia”.(10) As the Framework is specific to population-based, rather than high-risk, screening programs, there is a lack of clarity about transferability of criteria. However, the Framework criteria do stipulate that a screening program must be acceptable to “important subgroups such as target participants who are from culturally and linguistically diverse backgrounds, Aboriginal and Torres Strait Islander people, people from disadvantaged groups and people with a disability”.(10) An extensive search of the literature highlighted that there is very little information about the acceptability of LDCT screening to these population groups in Australia. Yet they are part of the high-risk population.(10) There are also considerable gaps in the evidence about the cost-effectiveness of LDCT screening in different settings, including Australia. The evidence base in this area is rapidly evolving and is likely to include new data from the NELSON trial and incorporate data about the costs of targeted- and immuno-therapies as these treatments become more widely available in Australia.
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