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Sample records for materiaux des composants

  1. Impact of Materials Defects on Engine Structures Integrity (L’Impact des Defauts des Materiaux sur l’Integrite des Structures des Moteurs)

    DTIC Science & Technology

    1993-04-01

    participants ont fait le point des aspects traitement et contr6le des mat~riaux. en mettant I’accent sur les materiaux constitutifs des disques moteur en...adapte. Pour le physicien. un -d~faur’" peut tres bien se resumer A une imperfection de Ia structure rericulaire d’un materiau. En science des materiaux ... materiaux sur l~integrite des structures des moteurs Defence Research Ag~ency Matenials & Structures Department Farnborough. Hants GUt 14 fITD Rovaume-Uni

  2. Caracterisation des proprietes acoustiques des materiaux poreux a cellules ouvertes et a matrice rigide ou souple

    NASA Astrophysics Data System (ADS)

    Salissou, Yacoubou

    L'objectif global vise par les travaux de cette these est d'ameliorer la caracterisation des proprietes macroscopiques des materiaux poreux a structure rigide ou souple par des approches inverses et indirectes basees sur des mesures acoustiques faites en tube d'impedance. La precision des approches inverses et indirectes utilisees aujourd'hui est principalement limitee par la qualite des mesures acoustiques obtenues en tube d'impedance. En consequence, cette these se penche sur quatre problemes qui aideront a l'atteinte de l'objectif global precite. Le premier probleme porte sur une caracterisation precise de la porosite ouverte des materiaux poreux. Cette propriete en est une de passage permettant de lier la mesure des proprietes dynamiques acoustiques d'un materiau poreux aux proprietes effectives de sa phase fluide decrite par les modeles semi-phenomenologiques. Le deuxieme probleme traite de l'hypothese de symetrie des materiaux poreux selon leur epaisseur ou un index et un critere sont proposes pour quantifier l'asymetrie d'un materiau. Cette hypothese est souvent source d'imprecision des methodes de caracterisation inverses et indirectes en tube d'impedance. Le critere d'asymetrie propose permet ainsi de s'assurer de l'applicabilite et de la precision de ces methodes pour un materiau donne. Le troisieme probleme vise a mieux comprendre le probleme de transmission sonore en tube d'impedance en presentant pour la premiere fois un developpement exact du probleme par decomposition d'ondes. Ce developpement permet d'etablir clairement les limites des nombreuses methodes existantes basees sur des tubes de transmission a 2, 3 ou 4 microphones. La meilleure comprehension de ce probleme de transmission est importante puisque c'est par ce type de mesures que des methodes permettent d'extraire successivement la matrice de transfert d'un materiau poreux et ses proprietes dynamiques intrinseques comme son impedance caracteristique et son nombre d'onde complexe. Enfin, le

  3. Elaboration de nouvelles approches micromecaniques pour l'optimisation des performances mecaniques des materiaux heterogenes

    NASA Astrophysics Data System (ADS)

    Aboutajeddine, Ahmed

    Les modeles micromecaniques de transition d'echelles qui permettent de determiner les proprietes effectives des materiaux heterogenes a partir de la microstructure sont consideres dans ce travail. L'objectif est la prise en compte de la presence d'une interphase entre la matrice et le renforcement dans les modeles micromecaniques classiques, de meme que la reconsideration des approximations de base de ces modeles, afin de traiter les materiaux multiphasiques. Un nouveau modele micromecanique est alors propose pour tenir compte de la presence d'une interphase elastique mince lors de la determination des proprietes effectives. Ce modele a ete construit grace a l'apport de l'equation integrale, des operateurs interfaciaux de Hill et de la methode de Mori-Tanaka. Les expressions obtenues pour les modules globaux et les champs dans l'enrobage sont de nature analytique. L'approximation de base de ce modele est amelioree par la suite dans un nouveau modele qui s'interesse aux inclusions enrobees avec un enrobage mince ou epais. La resolution utilisee s'appuie sur une double homogeneisation realisee au niveau de l'inclusion enrobee et du materiau. Cette nouvelle demarche, permettra d'apprehender completement les implications des approximations de la modelisation. Les resultats obtenus sont exploites par la suite dans la solution de l'assemblage de Hashin. Ainsi, plusieurs modeles micromecaniques classiques d'origines differentes se voient unifier et rattacher, dans ce travail, a la representation geometrique de Hashin. En plus de pouvoir apprecier completement la pertinence de l'approximation de chaque modele dans cette vision unique, l'extension correcte de ces modeles aux materiaux multiphasiques est rendue possible. Plusieurs modeles analytiques et explicites sont alors proposee suivant des solutions de differents ordres de l'assemblage de Hashin. L'un des modeles explicite apparait comme une correction directe du modele de Mori-Tanaka, dans les cas ou celui ci echoue a

  4. Etude de la transition tribologique entre le fretting et le meso-fretting pour des materiaux de contact electrique

    NASA Astrophysics Data System (ADS)

    Gagnon, Daniel

    Dans les installations electriques, les contacts sont toujours soumis a des contraintes alternees ou a des micro-deplacements. Il en resulte une corrosion par fretting, phenomene defini comme un type de deterioration de la surface qui se produit lorsque deux materiaux en contact sont soumis a des mouvements microscopiques d'oscillations de tres faible amplitude (0 a 100 mum). Ceci a pour effet de provoquer une degradation de la resistance de contact et une interruption du passage du courant. Ce phenomene a des repercussions considerables sur le plan pratique puisque les micro-deplacements de pieces en contact peuvent etre causes par la dilatation thermique differentielle des metaux, par des vibrations mecaniques, par la relaxation des contraintes ou par l'echauffement des contacts lorsqu'on interrompt et retablit le courant. Nous avons donc dans le cadre de cette these etudie plusieurs aspects du fretting (0--100 mum) et du meso-fretting (100 a 1000 mum) pour differents materiaux de contact electrique. Des travaux experimentaux ont ete realises a partir de deux montages reproduisant divers aspects de la degradation par le fretting. Un premier montage de fretting de type bille-plaque a ete entierement developpe a l'ETS et un second montage, de type fil-plaque a ete utilise en collaboration avec Hydro Quebec IREQ a Varennes. Plusieurs techniques de mesures et d'analyse relevant tant du domaine de la mecanique du contact que de la metallurgie ont ete utilisees pour traiter les resultats. L'influence du courant sur le taux d'usure et la force de friction a ete examinee pour divers materiaux de contacts. Des essais de fatigue thermique et electrique ont ete realises sur divers materiaux et lubrifiants de contact. Il a ete demontre que pour le domaine entre 100 mum et 1000 mum, le taux d'usure n'est pas le meme de 0 a 100 mum et au dela de 1000 mum. La plupart des materiaux evalues montrent un stade de comportement intermediaire dont le debut se situe entre 100 mum et

  5. Mecanique et mecanisme de la dechirure des materiaux textiles

    NASA Astrophysics Data System (ADS)

    Triki, Ennouri

    Cette thèse vise à apporter une contribution à l’étude et à la modélisation de la déchirure des textiles et des textiles enduits. Notons que la résistance à la déchirure est l’une des caractéristiques mesurées pour les équipements de protection contre les agresseurs mécaniques en milieu de travail. Jusqu'à présent, ce comportement en déchirure a été étudié en mesurant la force de déchirure et le travail de déchirure. De fait, aucun critère de rupture en déchirure n’existe actuellement. Par conséquent, en s’inspirant de la théorie du Griffith et de la mécanique de la rupture, une formulation d’un nouveau critère de rupture des structures textiles a été proposée. Cette approche offre la possibilité de déterminer d’une manière plus précise l’énergie nécessaire pour la création d’une nouvelle surface de rupture. Ce critère nous permet d’analyser l’effet des caractéristiques des tissus sur la variation de l’énergie de rupture. Cette étude montre que la résistance au glissement des fils dans la structure est le principal facteur qui contrôle la propagation de la fissure. En se basant sur la théorie de la mécanique de la rupture, un modèle de calcul de l’énergie de rupture par déchirure a été aussi élaboré. Ce modèle de déchirure relie l’énergie aux paramètres caractérisant les phénomènes affectant la déchirure des tissus, notamment la force de glissement et la force à la rupture des fils. Cette modélisation a tenu compte de certaines caractéristiques des tissus tels que l’épaisseur du matériau, la densité des fils, etc. Par l’étude de la variation de l’énergie de rupture par déchirure en fonction du rapport établi entre la force à la rupture et la force de glissement d’un fil ( FYB/FS), l’effet des mécanismes de la propagation de la fissure dans les tissus sur leur comportement en déchirure a été aussi observé. Les résultats obtenus

  6. Etude des defauts microscopiques et des proprietes optiques, electroniques et magnetiques du compose neodyme cerium oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Richard, Pierre

    La presente these, qui combine des mesures de diffusion Raman, de transmission infrarouge, de conductivite hyperfrequence et d'interferometrie ultrasonore sur les composes Nd 2-xCexCuO 4, traite des defauts d'oxygene, ainsi que des proprietes optiques, electroniques et magnetiques de ces materiaux. Les resultats experimentaux obtenus sont correles avec plusieurs donnees experimentales disponibles dans la litterature. D'abord, la caracterisation des modes Raman et des niveaux d'energie de champ cristallin de l'ion Nd3+ au moyen de techniques optiques, en fonction du dopage en cerium et du contenu en oxygene, permettent de conclure a la presence de defauts lies a une non-stoechiometrie en oxygene dans ces composes. En effet, des excitations de champ cristallin assignees a des ions Nd3+ en sites irreguliers sont observees, en plus des bandes d'absorption associees aux ions Nd3+ en site regulier, dans les spectres correspondant aux multiplets 4I11/2, 4I13/2 et 4I 15/2 de l'ion Nd3+. Les resultats experimentaux indiquent que, contrairement a la croyance largement repandue, les oxygenes apicaux, bien que presents dans les echantillons dopes, ne sont pas enleves lors du processus de reduction des echantillons necessaire pour faire apparaitre la supraconductivite dans cette famille de cuprates. Au contraire, des lacunes d'oxygene, dont le type varie en fonction du dopage, sont creees lors de ce processus. En particulier, il est montre dans ce travail que la reduction des echantillons dopes de maniere optimale conduit a la creation de lacunes d'oxygene dans les plans CuO2. Les consequences de telles lacunes sont largement discutees. En outre, il est suggere que de telles lacunes sont responsables de la perte de l'ordre antiferromagnetique a longue portee des ions Cu2+. Finalement, l'interaction d'echange anisotrope Nd3+-Cu 2+ dans le compose nondope est caracterisee au moyen de la transmission infrarouge sous champ magnetique. L'eclatement des doublets de Kramers mesure

  7. Synthese, etude structurale et electrochimique des materiaux d'electrode positive d'oxydes mixtes lithium cobalt nickel oxide (0 /= 1) pour les batteries rechargeables au lithium

    NASA Astrophysics Data System (ADS)

    Grincourt, Yves

    Depuis une dizaine d'annees, on observe un interet grandissant pour les batteries rechargeables au lithium de tension superieure a 4 volts. La commercialisation de ces batteries pour l'electronique grand marche tend de plus en plus a supplanter celle des accumulateurs Ni-Cd et Ni-MH, de tension nominate 1,2 V. Ces batteries au lithium font appel a des materiaux d'electrode positive (cathode a la decharge) du type oxydes mixtes de metaux de transition LiMnO 2, LiMn2O4, LiNiO2 ou LiCoO2. Si le compose LiCoO2 est relativement aise a synthetiser, il n'en demeure pas moins que le cobalt reste un metal plus couteux compare au nickel et au manganese. La synthese de LiNiO2, quart a elle, demeure un probleme du point de vue stoechiometrique. Un defaut de lithium (5 a 10% molaire) conduira a des proprietes electrochimiques mediocres de la batterie. Dans cette etude nous nous proposons donc de preparer par voie humide et par voie seche les materiaux d'electrode positive de la famille LiCoyNi1-yO2 aver (0 ≤ y ≤ 1) et d'etudier en detail l'influence du pourcentage de nickel et de cobalt sur les proprietes electrochimiques des oxydes mixtes Li-Ni-Co. Une des caracteristiques est la morphologie plus fine des poudres de materiaux, observes par microscopie electronique a balayage (MEB). Un traitement thermique a plus basse temperature (750°C) que pour LiCoO2 (850°C) ainsi qu'un leger exces de lithium dans la preparation, ont permis d'aboutir a un materiau de stoechiometrie quasi parfaite. Neanmoins, le role de pilfer joue par 2 a 4% de moles de Ni2+ presents sur les sites lithium, permet de conserver intacte la structure hexagonale de la maille entre deux cycles consecutifs. Afin de mieux comprendre l'influence du vieillissement dune demi-pile Li/LiMeO2 (Me = Ni, Co) a temperature ambiante, des etudes electrochimiques et d'impedance spectroscopique ont ete menees en parallele. Le vieillissement de la cellule s'accompagne seulement dune chute de son potentiel due a son auto

  8. Etude theorique des fluctuations structurales dans les composes organiques a dimensionnalite reduite

    NASA Astrophysics Data System (ADS)

    Dumoulin, Benoit

    Les systemes a dimensionnalite reduite constituent maintenant une branche entiere de la physique de la matiere condensee. Cette derniere s'est developpee rapidement au cours des dernieres annees, avec la decouverte des materiaux organiques qui presentent, justement, des proprietes physiques fortement anisotropes. Cette these presente une etude en trois parties de plusieurs composes organiques qui, bien que tres differents du point de vue de leurs compositions chimiques et de leurs proprietes physiques a haute temperature, subissent tous une instabilite structurale a tres basse temperature. De plus, dans chacun des cas, l'instabilite structurale est precedee d'un important regime fluctuatif a partir duquel les proprietes physiques changent de maniere significative. Notre etude suit un ordre chronologique inverse puisque nous nous attardons en premier lieu au cas de composes recemment decouverts: les composes de la famille des (BCPTTF)2X (X = PF6 , AsF6). Ces derniers sont des isolants magnetiques a la temperature ambiante et subissent une instabilite structurale de type spin-Peierls a une temperature appelee TSP. En particulier, nous nous interessons a l'etude des proprietes physiques de ces systemes dans le regime fluctuatif, qui precede cette instabilite. Notre etude theorique nous permet de comprendre en detail comment ces systemes s'approchent de l'instabilite struturale. Dans la seconde partie de cette these, nous etudions le regime fluctuatif (pre-transitionnel) observe experimentalement dans le compose de (TMTTF)2PF6. Ce compose organique, dont la structure s'apparente aux sels de Bechgaard, subit une instabilite de type spin-Peierls a une temperature T SP = 19K. Bien que ce compose possede la particularite d'etre un bon conducteur a la temperature ambiante, il subit une transition de type Mott-Hubbard a une temperature Trho ≈ 220K et devient alors un isolant magnetique, analogue aux composes de la famille des (BCPTTF)2X. Le regime fluctuatif precedant l

  9. Preface: Materiaux 2010

    NASA Astrophysics Data System (ADS)

    Cheikhrouhou, Abdelwaheb

    2012-02-01

    The national conference 'MATERIAUX 2010', which took place in Mahdia (Tunisia), from 4-7 November 2010 was organized by The 'Tunisian Materials Research Society: Tu-MRS' in collaboration with the Materials Physics Laboratory of Sfax 'LPM', Faculty of Sciences, Sfax University and the Research Unit ' Physique, Informatique et Mathématiques ', Faculty of Sciences, Gafsa University The First National Conference on Materials 'MATERIAUX 2006' was organized in Douz (Tunisia) in December 2006. This was followed by 'MATERIAUX 2007' held in Hammamet (Tunisia) in April 2007 and the National Conference 'MATERIAUX 2009' organized jointly with the Second 'Journées Internationales de la Physique des Matériaux et Applications: JIPMA 2009' in Gafsa (Tunisia) from 20-24 December 2009. 'MATERIAUX 2010' is intended to provide an excellent opportunity for National, Maghreb and International researchers to make their own work on materials known to a wider audience and to have discussions with other participants. This conference will also be an opportunity to exchange experiences, create and consolidate cooperation between different research structures in the Maghreb countries and also the countries around the Mediterranean. This conference will equally promote research development, contribution to collaboration between universities and the socio-economical milieu. More than 300 senior researchers, Professors, PhD and Masters students attended this conference from Tunisia, Algeria, Morocco, France, Spain and Canada. Several researchers, engineers and managers from industrial firms also attended. The conference consisted of plenary talks (8), oral contributions (40) and poster presentations (250). The topics of the Conference were: Nano-materials, nano-systems, thin films, surfaces and interfaces, applications Multifunctionnal materials, magnetic materials, dielectric materials, superconducting materials, applications,... Materials for electronics, informatics and communication

  10. Effet de la composition des materiaux composites sur la caracterisation et detection par ondes de Lamb

    NASA Astrophysics Data System (ADS)

    Ostiguy, Pierre-Claude

    Les matériaux composites sont de plus en plus utilisés en aéronautique. Leurs excellentes propriétés mécaniques et leur faible poids leur procurent un avantage certain par rapport aux matériaux métalliques. Ceux-ci étant soumis à diverses conditions de chargement et environnementales, ils sont suceptibles de subir plusieurs types d'endommagements, compromettant leur intégrité. Des méthodes fiables d'inspection sont donc nécessaires pour évaluer leur intégrité. Néanmoins, peu d'approches non destructives, embarquées et efficaces sont présentement utilisées. Ce travail de recherche se penche sur l'étude de l'effet de la composition des matériaux composites sur la détection et la caractérisation par ondes guidées. L'objectif du projet est de développer une approche de caractérisation mécanique embarquée permettant d'améliorer la performance d'une approche d'imagerie par antenne piézoélectriques sur des structures composite et métalliques. La contribution de ce projet est de proposer une approche embarquée de caractérisation mécanique par ultrasons qui ne requiert pas une mesure sur une multitude d'échantillons et qui est non destructive. Ce mémoire par articles est divisé en quatre parties, dont les parties deux A quatre présentant les articles publiés et soumis. La première partie présente l'état des connaissances dans la matière nécessaires à l'acomplissement de ce projet de maîtrise. Les principaux sujets traités portent sur les matériaux composites, propagation d'ondes, la modélisation des ondes guidées, la caractérisation par ondes guidées et la surveillance embarquée des structures. La deuxième partie présente une étude de l'effet des propriétés mécaniques sur la performance de l'algorithme d'imagerie Excitelet. L'étude est faite sur une structure isotrope. Les résultats ont démontré que l'algorithme est sensible à l'exactitude des propriétés mécaniques utilisées dans le modèle. Cette

  11. Etudes optiques de nouveaux materiaux laser: Des orthosilicates dopes a l'ytterbium: Le yttrium (lutetium,scandium) pentoxide de silicium

    NASA Astrophysics Data System (ADS)

    Denoyer, Aurelie

    La decouverte et l'elaboration de nouveaux materiaux laser solides suscitent beaucoup d'interet parmi la communaute scientifique. En particulier les lasers dans la gamme de frequence du micron debouchent sur beaucoup d'applications, en telecommunication, en medecine, dans le domaine militaire, pour la, decoupe des metaux (lasers de puissance), en optique non lineaire (doublage de frequence, bistabilite optique). Le plus couramment utilise actuellement est le Nd:YAG dans cette famille de laser, mais des remplacants plus performants sont toujours recherches. Les lasers a base d'Yb3+ possedent beaucoup d'avantages compares aux lasers Nd3+ du fait de leur structure electronique simple et de leur deterioration moins rapide. Parmi les matrices cristallines pouvant accueillir l'ytterbium, les orthosilicates Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5 se positionnent tres bien, du fait de leur bonne conductivite thermique et du fort eclatement de leur champ cristallin necessaire a l'elaboration de lasers quasi-3 niveaux. De plus l'etude fine et systematique des proprietes microscopiques de nouveaux materiaux s'avere toujours tres interessante du point de vue de la recherche fondamentale, c'est ainsi que de nouveaux modeles sont concus (par exemple pour le champ cristallin) ou que de nouvelles proprietes inhabituelles sont decouvertes, menant a de nouvelles applications. Ainsi d'autres materiaux dopes a l'ytterbium sont connus pour leurs proprietes de couplage electron-phonon, de couplage magnetique, d'emission cooperative ou encore de bistabilite optique, mais ces proprietes n'ont encore jamais ete mises en evidence dans Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5. Ainsi, cette these a pour but l'etude des proprietes optiques et des interactions microscopiques dans Yb:Y2SiO 5, Yb:Lu2SiO5 et Yb:Sc2SiO5. Nous utilisons principalement les techniques d'absorption IR et de spectroscopie Raman pour determiner les excitations du champ cristallin et les modes de vibration dans le materiau

  12. Detection de l'initiation de la delamination des materiaux composites par suivi de l'emission acoustique

    NASA Astrophysics Data System (ADS)

    Silversides, Ian

    Cette étude, basée sur la surveillance des ondes d'émission acoustique (E.A.), présente le développement d'une approche de prédiction de l'initiation de la délamination de pièces composites soumises à des chargements statiques et en fatigue. La surveillance des ondes d'E.A. fait parti d'un nombre restreint de méthodes pouvant détecter, en continu, l'apparition et la croissance de dommages dans les matériaux composites. L'approche est comparée à des méthodes conventionnelles ainsi qu'à une modélisation numérique pour des composites à fibre de carbone unidirectionnels et tissés, sur une gamme de rapports de mode mixte. Le présent mémoire met en lumière les différentes étapes abordées durant l'étude. L'utilisation des matériaux composites est mise en contexte au premier chapitre. La complexité des matériaux composites ainsi que la nécessité de modèles de prédiction fiables sont soulignées. Le deuxième chapitre contient une revue de la littérature et présente les outils disponibles pour analyser le délaminage et bâtir un modèle prédictif de sa propagation. Les sujets traités sont la délamination dans un contexte de mécanique de la rupture, la modélisation numérique d'une propagation de fissure, l'approche du monitorage par émission acoustique puis l'analyse fractographiques des surfaces de rupture. Les résultats des essais mécaniques et de la modélisation sont présentés sous forme d'article dans le troisième chapitre. Des essais statiques et en fatigue ont permis de calculer le taux de restitution d'énergie de déformation à l'initiation de la délamination selon des méthodes classiques pour ensuite les comparer à une méthode développée, basée sur le suivi des ondes d'émission acoustique. Une série d'essais de propagation de la délamination en fatigue ont permis d'observer des corrélations entre les émissions acoustiques, la longueur de la délamination, la vitesse de croissance des fissures et la s

  13. Realisation de composants tout-fibre passifs bases sur des fibres optiques a deux coeurs

    NASA Astrophysics Data System (ADS)

    Jacob Poulin, Anne C.

    2002-01-01

    Les composants passifs tout-optique sont des elements de choix dans les systemes de communications optiques. Cette these presente l'utilisation experimentale de fibres a deux coeurs dissimilaires pour la realisation de filtres passe-bande. Les fibres a deux coeurs ont la particularite de favoriser un couplage d'un coeur a l'autre a intervalles reguliers lorsque les coeurs sont exactement identiques. Dans le cas ou une legere difference apparait, ce couplage est rapidement reduit a zero. La premiere partie de la these montre comment, par l'emploi d'une geometrie de fibre appropriee, il est possible de compenser cette desyntonisation et de fabriquer des coupleurs 100%. Les filtres obtenus ayant toutefois une largeur de bande trop grande pour les besoins du marche des communications optiques, il est montre dans la deuxieme partie de la these comment, en alliant la technologie des reseaux de Bragg avec celle des coupleurs, il est possible de realiser des filtres operant en transmission et possedant d'excellentes caracteristiques spectrales, toujours avec ces memes fibres a deux coeurs.

  14. Synthese et utilisation de fibres cellulosiques phosphatees pour la valorisation de la fibre vegetale dans l'amelioration des proprietes de surface du papier et la fabrication de materiaux ignifuges

    NASA Astrophysics Data System (ADS)

    Lentsolo Yalli, Gym Clerc

    Dans cette etude, nous souhaitions principalement greffer des groupements phosphates directement sur la cellulose comme materiau modele, et par la suite transposer les conditions optimales du design concu pour la cellulose, determine par modelisation a l'aide de l'outil JMP, sur la pate kraft. Ensuite, evaluer les proprietes physico-chimiques, optiques, d'hydrophilie, thermiques et d'inflammabilite des materiaux fabriques (feuilles ou pastilles fabriquees) a partir des fibres phosphorylees. Pour ce faire, nous avons pretraite la cellulose et la pate kraft dans une solution aqueuse de 10 a 15 % de LiCl a 70°C pendant 7 heures. Par la suite, nous avons procede a la reaction de phosphorylation in situ avec l'acide phosphorique et l'uree, dans des conditions de temperatures et de reactifs decrites par un design experimental, pendant 3 heures. La reaction de phosphorylation s'est realisee avec succes pour l'ensemble des resultats sur la cellulose, avec des taux de greffage variables selon les conditions operatoires. Les degres de substitutions (DSP), determines par ICP-OES, et les degres de polymerisation (DP), determines par viscosimetrie, etaient aussi variables, selon les conditions. L'etude des parametres experimentaux a permis de determiner les conditions optimales transposables sur la pate kraft (DSP = 1,47 et DP = 142,42 pour la cellulose, qui represente un taux de coupure de 38% de la fibre) et les facteurs critiques de la reaction. Les resultats de la reaction sur la fibre ont permis, non seulement de constater que les conditions utilisees pour la cellulose n'etaient directement transposables a la fibre, mais permettaient quand d'obtenir un DSP interessant ≥ a 1 avec un taux de coupure de 50 a 60 %. La structure du produit principal de la reaction (le sel de calcium du pyrophosphate d'ester de cellulose ou de pate kraft) a ete determinee par les analyses FTIR, XPS, RMN-13C et RMN-31P. L'etude de l'effet de la reaction de phosphorylation sur les proprietes

  15. Etude sur les tendons en materiaux composites et leur application aux ancrages postcontraints

    NASA Astrophysics Data System (ADS)

    Chennouf, Adil

    L'objectif general de la presente these est d'evaluer le comportement a l'arrachement et au fluage d'ancrages injectes constitues de tendons en materiaux composites afin d'etablir des recommandations plus appropriees et realistes pour le dimensionnement et la conception. Quatre types de tendons en materiaux composites, deux a base de fibres d'aramide et deux a base de fibres de carbone, ont ete utilises dans l'etude. Les travaux de recherche de cette these ont porte notamment sur: (I) Une caracterisation physique et mecanique des tendons en materiaux composites utilises dans l'etude. (II) Une etude en laboratoire sur les coulis de scellement. La premiere etape de cette etude a concerne le developpement d'un coulis de scellement performant adapte aux tendons en materiaux composites et a differentes situations d'injection. La seconde etape a traite des essais de caracterisations physique et mecanique du coulis de scellement developpe comparativement a trois coulis de scellement usuels d'un meme rapport E/L de 0,4. (III) Une etude sur des modeles reduits d'ancrages injectes. (IV) Une etude sur des modeles d'ancrages a grande echelle. La synthese de ces etudes a permis d'enoncer les principales conclusions suivantes: (1) Les valeurs moyennes des charges de rupture des tendons en materiaux composites ont ete de 1% a 29% superieures a celles specifiees par les manufacturiers. (2) L'etude sur les coulis de scellement a permis le developpement de coulis de ciment repondant aux criteres fixes, soient une grande stabilite, une bonne fluidite, une legere expansion et de bonnes caracteristiques mecaniques. (3) Les tendons en materiaux composites ont montre des contraintes d'adherence maximum superieures a celles des tendons en acier. (4) Le type de fibre, la configuration et le fini de surface des tendons en materiaux composites gouvernent leur resistance a l'adherence. (5) L'introduction de sable et d'autres ajouts comme les fines de silice et la poudre d'aluminium au coulis

  16. Advances in Components for Active and Passive Airborne Sensors (Progres des Composants pour les Systemes des Detection Active et Passive Aeroportes)

    DTIC Science & Technology

    1990-09-01

    WJ.Ilocchi, Jr SESSION V - OPTIC APPLICATIONS TO AVIONICS Fibres Optiques Sp~ciales et Capteurs pour I’A~onautique 16 (Special Optical Fibers and...D.R.Bates Ai RAPPORT D’EVALUATION TECHNIQUE Lcs Progr~s des Composants pour Capteurs Actifs et Passifs Aroport&s Confidrence de sp~cialistes de ’AGARD, Bath...particuli~rement au niveau en mati~re de r~alisation de composants et de des capteurs , qui constituent souvent le maillon circuits. critique du syst

  17. Materiaux composites supraconducteurs

    NASA Astrophysics Data System (ADS)

    Kerjouan, Philippe; Boterel, Florence; Lostec, Jean; Bertot, Jean-Paul; Haussonne, Jean-Marie

    1991-11-01

    The new superconductor materials with a high critical current own a large importance as well in the electronic components or in the electrotechnical devices fields. The deposit of such materials with the thick films technology is to be more and more developped in the years to come. Therefore, we tried to realize such thick films screen printed on alumina, and composed mainly of the YBa2CU3O{7-δ} material. We first realized a composite material glass/YBa2CU3O{7-δ}, by analogy with the classical screen-printed inks where the glass ensures the bonding with the substrate. We thus realized different materials by using some different classes of glass. These materials owned a superconducting transition close to the one of the pure YBa2CU3O{7-δ} material. We made a slurry with the most significant composite materials and binders, and screen-printed them on an alumina substrate preliminary or not coated with a diffusion barrier layer. After firing, we studied the thick films adhesion, the alumina/glass/composite material interfaces, and their superconducting properties. Les nouveaux matériaux supraconducteurs à haute température critique ont potentiellement un rôle important à jouer dans le domaine de l'électronique et de l'électrotechnique. En particulier, le dépôt d'oxydes supraconducteurs sur divers types de substrats est une technologie amenée à se développer. Nous avons donc entrepris une étude dont l'objet est la réalisation de conducteurs sérigraphiés sur alumine et composés essentiellement du matériau YBa2CU3O{7-δ}. Nous avons tout d'abord cherché à réaliser un composite verre/YBa2CU3O{7-δ}, par analogie au principe de réalisation de couches conductrices sérigraphiées, le verre permettant d'obtenir une liaison physico-chimique avec le substrat. Une étude préliminaire a permis de réaliser divers matériaux composites massifs, utilisant différentes familles de verres. Ces matériaux massifs, se présentant sous la forme de barreaux de

  18. Etude microdosimetrique de l'influence des materiaux sur l'efficacite biologique d'une source d'iode-125

    NASA Astrophysics Data System (ADS)

    Taschereau, Richard

    Cette these concerne les implants permanents pour la prostate. Les isotopes employes, le 103Pd et l'125I, semblent produire les memes resultats cliniques: le premier a cause d'une radiation plus efficace et le second a cause de sa demi-vie plus longue. La recherche utilise le cadre theorique de la microdosimetrie et des simulations Monte Carlo. Elle propose d'employer le spectre d'ejection dans le calcul de l'efficacite; ce changement fait passer l'efficacite relative du 103Pd de 10% a 5%. Elle montre ensuite qu'il est possible d'ameliorer l'efficacite de la radiation de 125I par l'exploitation des rayons X caracteristiques de la capsule. Une source amelioree faite de molybdene et d'yttrium est donnee en exemple. Elle procure une radiation de 5--7% plus efficace, ce qui surclasse les deux sources existantes. Les applications ne se limitent pas au traitement de la prostate; le traitement du melanome oculaire et la curietherapie endovasculaire pourraient en beneficier.

  19. Evaluation experimentale et theorique du comportement a la flexion de nouveaux poteaux en materiaux composites

    NASA Astrophysics Data System (ADS)

    Metiche, Slimane

    La demande croissante en poteaux pour les differents reseaux d'electricite et de telecommunications a rendu necessaire l'utilisation de materiaux innovants, qui preservent l'environnement. La majorite des poteaux electriques existants au Canada ainsi qu'a travers le monde, sont fabriques a partir de materiaux traditionnels tel que le bois, le beton ou l'acier. Les motivations des industriels et des chercheurs a penser a d'autres solutions sont diverses, citons entre autre: La limitation en longueur des poteaux en bois ainsi que la vulnerabilite des poteaux fabriques en beton ou en acier aux agressions climatiques. Les nouveaux poteaux en materiaux composites se presentent comme de bons candidats a cet effet, cependant; leur comportement structural n'est pas connu et des etudes theoriques et experimentales approfondies sont necessaires avant leur mise en marche a grande echelle. Un programme de recherche intensif comportant plusieurs projets experimentaux, analytiques et numeriques est en cours a l'Universite de Sherbrooke afin d'evaluer le comportement a court et a long termes de ces nouveaux poteaux en Polymeres Renforces de Fibres (PRF). C'est dans ce contexte que s'inscrit la presente these, et notre recherche vise a evaluer le comportement a la flexion de nouveaux poteaux tubulaires coniques fabriques en materiaux composites par enroulement filamentaire et ce, a travers une etude theorique, ainsi qu'a travers une serie d'essais de flexion en "grandeur reelle" afin de comprendre le comportement structural de ces poteaux, d'optimiser la conception et de proposer une procedure de dimensionnement pour les utilisateurs. Les poteaux en Polymeres Renforces de Fibres (PRF) etudies dans cette these sont fabriques avec une resine epoxyde renforcee de fibres de verre type E. Chaque type poteaux est constitue principalement de trois zones ou les proprietes geometriques (epaisseur, diametre) et les proprietes mecaniques sont differentes d'une zone a l'autre. La difference

  20. Aircraft Operations on Repaired Runways (l’Exploitation des Aeronefs sur les Pistes Refaites)

    DTIC Science & Technology

    1990-08-01

    procedures d’cxploitaiion des acronels sur des pistes repar&s. le Panel AGiARI) des Structures ct Materiaux at organisii des reunions pour faire Ic...existing 4.6 Resistance des avions. AIR 2(4E L - length of obstacle H - height/depth of obstacle Single obstacle Repeated obstacles (STOL aircraft

  1. Fluctuations Magnetiques des Gaz D'electrons Bidimensionnels: Application AU Compose Supraconducteur LANTHANE(2-X) Strontium(x) Cuivre OXYGENE(4)

    NASA Astrophysics Data System (ADS)

    Benard, Pierre

    Nous presentons une etude des fluctuations magnetiques de la phase normale de l'oxyde de cuivre supraconducteur La_{2-x}Sr _{x}CuO_4 . Le compose est modelise par le Hamiltonien de Hubbard bidimensionnel avec un terme de saut vers les deuxiemes voisins (modele tt'U). Le modele est etudie en utilisant l'approximation de la GRPA (Generalized Random Phase Approximation) et en incluant les effets de la renormalisation de l'interaction de Hubbard par les diagrammes de Brueckner-Kanamori. Dans l'approche presentee dans ce travail, les maximums du facteur de structure magnetique observes par les experiences de diffusion de neutrons sont associes aux anomalies 2k _{F} de reseau du facteur de structure des gaz d'electrons bidimensionnels sans interaction. Ces anomalies proviennent de la diffusion entre particules situees a des points de la surface de Fermi ou les vitesses de Fermi sont tangentes, et conduisent a des divergences dont la nature depend de la geometrie de la surface de Fermi au voisinage de ces points. Ces resultats sont ensuite appliques au modele tt'U, dont le modele de Hubbard usuel tU est un cas particulier. Dans la majorite des cas, les interactions ne determinent pas la position des maximums du facteur de structure. Le role de l'interaction est d'augmenter l'intensite des structures du facteur de structure magnetique associees a l'instabilite magnetique du systeme. Ces structures sont souvent deja presentes dans la partie imaginaire de la susceptibilite sans interaction. Le rapport d'intensite entre les maximums absolus et les autres structures du facteur de structure magnetique permet de determiner le rapport U_ {rn}/U_{c} qui mesure la proximite d'une instabilite magnetique. Le diagramme de phase est ensuite etudie afin de delimiter la plage de validite de l'approximation. Apres avoir discute des modes collectifs et de l'effet d'une partie imaginaire non-nulle de la self-energie, l'origine de l'echelle d'energie des fluctuations magnetiques est examinee

  2. Qualification sous irradiation du crayon cea: de la conception des composants a l'irradiation d'assemblages en reacteur de puissance

    NASA Astrophysics Data System (ADS)

    Marin, Jean-François; Pillet, Claude; François, Bernard; Morize, Pierre; Petitgrand, Sylvie; Atabek, Rose-Marie; Houdaille, Brigitte

    1982-04-01

    Cet article résume les principaux résultats obtenus au CEA au cours des dix dernières années dans la conception, la qualification et la fabrication des différents éléments originaux constitutifs d'un assemblage de réacteur à eau pressurisée, notamment: l'oxyde UO 2 obtenu par le procédé du Double Cycle Inverse, la gaine en zircaloy 4 recris talllsée, la grille à ressort papillon, la structure à grilles coulissantes. Les etudes et essais hors-pile de comportement thermomécanique du crayon et thermohydraulique des composants de l'assemblage, les irradiations paramétriques de crayons jusqu'à une combustion massique élevée, la validation à partir d'examens aprés irradiation des principaux modèles introduits dans les calculs de conception, enfin l'introduction en réacteur prototype, puis en réacteur de puissance d'assemblages comportant ces différents éléments, constituent les principales étapes de ce développement.

  3. Incertitude dans les mesures de courant : un obstacle dans la caractérisation des composants en électronique de puissance

    NASA Astrophysics Data System (ADS)

    Farjah, E.; Barbaroux, J.; Perret, R.

    1993-07-01

    The aim of this paper is to clarify the need for the most accurate current measurement applied to the characterization of the power electronic components. The focus is on the behaviour of the normally used high quality high bandwidth current transformers and other sensors to a fast varying high di/dt test current furnished by a new developed test current generator. In this paper after explaining the new strategy of the test generator, different current transformers are tested and characterized and a detailed comparative experimental study is carried out using a non-inductive shunt as the reference. Finally some general remarks and the necessary precautions and different measurement problems are listed and discussed. Le but de cet article est d'essayer de lever les obstacles rencontrés lors des mesures de courant servant à la caractérisation des composants en électronique de puissance. Nous nous sommes penchés sur les différences entre les réponses de quelques capteurs de haute qualité. Après une brève explication du principe d'un générateur de courant de test spécialement conçu pour cette étude, nous comparons les réponses de plusieurs transformateurs de courant par rapport à un shunt aselfique pris pour référence. Enfin nous abordons les différents aspects concernant les précautions qu'il est nécessaire de prendre pour réaliser ce type de mesure.

  4. Etude de la resistance en fatigue des materiaux bitumineux

    NASA Astrophysics Data System (ADS)

    Touhara, Radouen

    The goal of this research program is to evaluate and characterize the fatigue behaviour of two GB20 hot mix asphalt made with two different bitumen. One of them is made in laboratory with a straight-run PG58-28 bitumen, while the second mix was made in an asphalt plant with a PG64-28 bitumen. Two characterization tests, in homogeneous conditions, done in traction/compression on cylindrical specimens are used in this study. First, a complex modulus test performed in the linear viscoelasticity (LVE) domain is used to characterize the mixes and second, a fatigue test is done to evaluate the mixes performances. The fatigue tests were done in strain controlled at different amplitude. All fatigue tests were performed at 10Hz, but at different temperatures (10, 20 and 30°C) in order to evaluate the effect of the temperature on the fatigue behaviour of those mixes. In this document, the results are presented, and the analysis of the results as a function of the grade of bitumen, the tests’ temperature and the dispersion of the results is performed. Also, the DGCB method is applied to the fatigue results to calculate the rate of damage per cycle followed by a study of the different failure criteria (Nf) to predict the fatigue life of asphalt mixes. Keywords: bituminous materials, fatigue, complex modulus, Damage.

  5. Un accumulateur echangeur de chaleur hybride pour la gestion simultanee des energies solaire et electrique

    NASA Astrophysics Data System (ADS)

    Ait Hammou, Zouhair

    Cette etude porte sur la conception d'un accumulateur echangeur de chaleur hybride (AECH) pour la gestion simultanee des energies solaire et electrique. Un modele mathematique reposant sur les equations de conservation de la quantite d'energie est expose. Il est developpe pour tester differents materiaux de stockage, entre autres, les materiaux a changement de phase (solide/liquide) et les materiaux de stockage sensible. Un code de calcul est mis en eeuvre sur ordinateur, puis valide a l'aide des resultats analytiques et numeriques de la litterature. En parallele, un prototype experimental a echelle reduite est concu au laboratoire afin de valider le code de calcul. Des simulations sont effectuees pour etudier les effets des parametres de conception et des materiaux de stockage sur le comportement thermique de l'AECH et sur la consommation d'energie electrique. Les resultats des simulations sur quatre mois d'hiver montrent que la paraffine n-octadecane et l'acide caprique sont deux candidats souhaitables pour le stockage d'energie destine au chauffage des habitats. L'utilisation de ces deux materiaux dans l'AECH permet de reduire la consommation d'energie electrique de 32% et d'aplanir le probleme de pointe electrique puisque 90% de l'energie electrique est consommee durant les heures creuses. En plus, en adoptant un tarif preferentiel, le calcul des couts lies a la consommation d'energie electrique montre que le consommateur adoptant ce systeme beneficie d'une reduction de 50% de la facture d'electricite.

  6. Strategies to Mitigate Obsolescence in Defense Systems Using Commercial Components (Strategies visant a attenuer l’obsolescence des systemes par l’emploi de composants du commerce)

    DTIC Science & Technology

    2001-06-01

    industrielle de défense US, la gestion de l’obsolescence, et ce qui a été appelée - Les sources de fabrication en diminution et les pénuries de...et a fait allusion aux avantages et inconvénients y associés. Des outils et des méthodologies de gestion permettant de faire face à la menace de... Gestion de l’obsolescence et outils – Nouvelles architectures et nouveaux concepts pour combattre l’obsolescence – Stratégies et initiatives pour

  7. Recorder Composer

    ERIC Educational Resources Information Center

    Stephenson, Kimberly

    2012-01-01

    The best moments happen when students begin to realize how much power they have and use that power to create. Composing as they master different instrumental stages helps students make composition and performance a natural step in learning. A step-by-step process (rhythm notation, add pitches, copy to a five-line staff, check work, and play) keeps…

  8. Adsorption de gaz sur les materiaux microporeux modelisation, thermodynamique et applications

    NASA Astrophysics Data System (ADS)

    Richard, Marc-Andre

    2009-12-01

    Nos travaux sur l'adsorption de gaz dans les materiaux microporeux s'inscrivent dans le cadre des recherches visant a augmenter l'efficacite du stockage de l'hydrogene a bord des vehicules. Notre objectif etait d'etudier la possibilite d'utiliser l'adsorption afin d'ameliorer l'efficacite de la liquefaction de l'hydrogene des systemes a petite echelle. Nous avons egalement evalue les performances d'un systeme de stockage cryogenique de l'hydrogene base sur la physisorption. Comme nous avons affaire a des plages de temperatures particulierement etendues et a de hautes pressions dans la region supercritique du gaz, nous avons du commencer par travailler sur la modelisation et la thermodynamique de l'adsorption. La representation de la quantite de gaz adsorbee en fonction de la temperature et de la pression par un modele semi-empirique est un outil utile pour determiner la masse de gaz adsorbee dans un systeme mais egalement pour calculer les effets thermiques lies a l'adsorption. Nous avons adapte le modele Dubinin-Astakhov (D-A) pour modeliser des isothermes d'adsorption d'hydrogene, d'azote et de methane sur du charbon actif a haute pression et sur une grande plage de temperatures supercritiques en considerant un volume d'adsorption invariant. Avec cinq parametres de regression (incluant le volume d'adsorption Va), le modele que nous avons developpe permet de tres bien representer des isothermes experimentales d'adsorption d'hydrogene (de 30 a 293 K, jusqu'a 6 MPa), d'azote (de 93 a 298 K, jusqu'a 6 MPa) et de methane (de 243 a 333 K, jusqu'a 9 MPa) sur le charbon actif. Nous avons calcule l'energie interne de la phase adsorbee a partir du modele en nous servant de la thermodynamique des solutions sans negliger le volume d'adsorption. Par la suite, nous avons presente les equations de conservation de la niasse et de l'energie pour un systeme d'adsorption et valide notre demarche en comparant des simulations et des tests d'adsorption et de desorption. En plus de l

  9. My Career: Composer

    ERIC Educational Resources Information Center

    Morganelli, Patrick

    2013-01-01

    In this article, the author talks about his career as a composer and offers some advice for aspiring composers. The author works as a composer in the movie industry, creating music that supports a film's story. Other composers work on television shows, and some do both television and film. The composer uses music to tell the audience what kind of…

  10. Contribution a l'etude des mecanismes de l'adhesion de la glace a differents materiaux et application a l'evaluation des materiaux glaciophobes

    NASA Astrophysics Data System (ADS)

    Ghalmi, Zahira

    Several Nordic countries with cold climates like Canada are often subjected to ice storms causing major economic and social losses. Ice or sticky snow adhesion on power network equipment can be a significant issue in transmission and distribution of electrical energy for companies operating in these regions. The costs of such events can be substantial, particularly due to the cessation of economic activities, equipment failures, deicing techniques (active methods), and population safety. Because of such events, power companies have understood the need to develop so-called superhydrophobic and/or icephobic surfaces, which can significantly reduce ice adhesion (passive methods). Several studies have led to the development of a variety of new nanostructured surfaces using various strategies. These studies have led to the design of superhydrophobic surfaces with contact angles greater than 150 and low ice adhesion strength. In order to optimally reduce the ice adhesion strength on different substrates, better understanding of the various mechanisms involved in the icing process is essential. It is in this context and within the framework of Canada's research chair on atmospheric icing of power networks (INGIVRE) that this thesis was carried out, aiming to improve the knowledge of atmospheric icing, and explain the forces involved at the ice/substrate interface. Furthermore, the effect of contact angle, surface roughness and porosity on icing and ice/substrate interface was investigated. This study clearly showed that the electrostatic, van der Waals and hydrogen bond forces are the main contributors to ice adhesion to a surface at the molecular level. The electrostatic energy, based on the principle of image charge, depends on the type of material in contact with the ice, the distance between the ice and the material, and the types of ice surface defects. The van der Waals energy depends on the material type, the thickness of the liquid water layer, and the temperature. For its part, the energy associated with hydrogen bonds depends on the material type, temperature, droplet mass, as well as on the static and sliding contact angles. Among these three forces, the electrostatic energy is the largest. Whereas the hydrogen bond energy is larger than the van der Waals energy. However, the latter is always present as long as ice is in contact with a solid surface. The experimental study showed that ice adhesion strength depends on the surface roughness of the substrate. In the case of metals with a thin natural protective oxide layer, higher roughness leads to higher ice adhesion strength. In other words, polished metallic surfaces exhibit lower ice adhesion strengths. However, in the case of anodized aluminum surfaces coated with PTFE, the roughened needle-like structure resulted in lower ice adhesion. The experimental results showed that PTFE coatings remain resistant to icing/deicing cycles. Even after 15 icing/deicing cycles, surfaces remain hydrophobic with a static contact angle greater than 130°.

  11. Etude du revenu de l'acier z 10 CDNbV0902 (type 9% Cr, 2% Mo + Nb,V) envisage pour la realisation de certains composants des reacteurs a neutrons rapides

    NASA Astrophysics Data System (ADS)

    Pelletier, M.; Vilar, R. M.; Cizeron, G.

    1982-02-01

    Après trempe depuis 1100°C, l'acier étudié est formé de ferrite stable à haute température et de martensite. Au cours de revenus anisothermes, la phase martensitique est le siège de la précipitation successive de carbures des types M 3C, M 7C 3 et M 2C, ces deux derniers étant responsables d'un durcissement secondaire significatif. Aux températures plus élevées, ces carbures se dissolvent tandis qu'apparaissent des carbures des types M 23C 6 et M 6C. La phase ferritique initialement sursaturée est, par ailleurs, le siège d'une précipitation de carbures des types M 2C et M 23C 6.

  12. Composing in Public

    ERIC Educational Resources Information Center

    Heintz, Anne

    2011-01-01

    The central premise of this project is that researching student communication and composing actions in light of audience will illuminate particular features of student composing processes in 21st century interdisciplinary contexts. Students in this study took part in a six week inquiry unit about their local area. Data generated included student…

  13. Conception axiomatique des joints hybrides a recouvrement simple en materiaux composites

    NASA Astrophysics Data System (ADS)

    Ouellet, Marc

    Minimizing weight is a primary objective in every system design in the aerospace and automotive industry. Therefore, the use of composite materials has become an integral part of the design of mechanical components. However, in composite structure design, their complexity normally makes it impossible to design them as a single part. This leads to the necessity of using joints. Sadly, these joints introduce discontinuities in the stress distribution within the components and are often the sites of stress concentration. Therefore, they may limit the performance of a structure, in addition to increasing the overall mass significantly due to the use of mechanical fasteners such as bolts and rivets. This is why bonded joints are increasingly popular. They are much lighter than bolted or riveted joints and are often more rigid. Unfortunately, it is very difficult to inspect a bonded joint for defects since the presence of cracks in the adhesive cannot be observed with the naked eye. The main objective of this work is to propose a new design methodology for hybrid joints. To accomplish this, it is necessary to establish reliable analysis tools to improve our understanding of the behavior of these joints when subjected to an external force. A better understanding of the interactions between the parameters is also required. To improve our knowledge on the subject, a literature review was conducted. This review was structured as to emphasize on the behavior of hybrid single lap joints when subjected to an external force in tension. Following this literature review, an analysis of the stress distribution within the joint was carried out using a finite element model. The model and the results were compared with those from two papers in order to validate the quality of representation. Subsequently, a modification was made to an existing analytical model in order to add the bolts' preload as a parameter. These two models, namely the finite element model and the analytical model, were then used for a sensitivity study using a design of experiments. To perform this analysis, a kriging model was used to reduce the computing time. Finally, the hybrid single lap joint was analyzed using axiomatic design in order to propose new approach to design these joints. The results of this work can be divided into three parts. First, an analytical model identified in the literature review has been improved to take into account the bolts' preload. The results are satisfactory within the limitations of the original model. It must be pointed out that this model does not consider the non-linear behavior of materials used in the joint, which can lead to poor reliability when highly non-linear materials are used. The sensitivity analysis carried out using the analytical model and the finite element model identified the influence of the parameters on the mechanical performances of the joint. It should be noted that the width of the joint is one of the most important parameter, as well as the thickness of the adherents. The sensitivity analysis also identified the notable effect of the radial clearance of the bolt shank. This parameter should be minimized in order to maximize performances. Finally, the geometry obtained with the axiomatic design and through physical integration reduced the maximum peel stress considerably. The use of washers based on Belleville springs allowed to significantly increase the area affected by the bolts' preload. Therefore, this final geometry should significantly increase the maximum external load that can be supported by the joint and increase its fatigue life. Finally, an improved geometry was proposed using the theory of axiomatic design. The use of chamfers at the ends of the adherents, the addition of modified washers and the use of a stiffer adhesive between the two bolts have significantly reduced the maximum peel stress in the adhesive layer. These changes have also increased the rigidity of the joint. However, analyzes have not demonstrated a decrease in the maximum shear stress inside the adhesive. Therefore, further work should be considered to assess the effect of some parameters of the improved joint on the distribution of shear stress in the adhesive layer. Among the parameters to consider, the ratio between the surfaces bonded by each of the two adhesives and the dimensions of the chamfers and the modified washers should be analyzed. (Abstract shortened by UMI.).

  14. Caracterisation des proprietes dielectriques de materiaux composites a base de polyethylene terephtalate recycle

    NASA Astrophysics Data System (ADS)

    Mebarki, Fouzia

    The aim of this study is to examine the possibility of using thermoplastic composite materials for electrical applications such as supports of automotive engine ignition systems. We are particularly interested in composites based on recycled polyethylene terephtalate (PET). Conventional isolations like PET cannot meet the new prescriptive requirements. The introduction of reinforcement materials, such as glass fibers and mica can improve the mechanical characteristics of these materials. However, this enhancement may also reduce electrical properties especially since these composites have to be used under severe thermal and electric stresses. In order to estimate PET composite insulation lifetimes, accelerated aging tests were carried out at temperatures ranging from room temperature to 140°C and at a frequency of 300Hz. Studies at high temperature will help to identify the service temperature of candidate materials. Dielectric breakdown tests have been made on a large number of samples according to the standard of dielectric strength tests of solid insulating ASTM D-149. These tests have to identify the problematic samples and to check solid insulation quality. The different knowledge gained from this analysis was used to predict material performance. This will give the company the possibility to improve existing formulations and subsequently develop a material having electrical and thermal properties suitable for this application.

  15. Application de la technologie des materiaux sol-gel et polymere a l'optique integree

    NASA Astrophysics Data System (ADS)

    Saddiki, Zakaria

    2002-01-01

    With the advancement of optical telecommunication systems, "integrated optics" and "optical interconnect" technology are becoming more and more important. The major components of these two technologies are photonic integrated circuits (PICs), optoelectronic integrated circuits (OEICs), and optoelectronic multichip modules ( OE-MCMs). Optical signals are transmitted through optical waveguides that interconnect such components. The principle of optical transmission in waveguides is the same as that in optical fibres. To implement these technologies, both passive and active optical devices are needed. A wide variety of optical materials has been studied, e.g., glasses, lithium niobate, III-V semiconductors, sol-gel and polymers. In particular, passive optical components have been fabricated using glass optical waveguides by ion-exchange, or by flame hydrolysis deposition and reactive ion etching (FHD and RIE ). When using FHD and RIE, a very high temperatures (up to 1300°C) are needed to consolidate silica. This work reports on the fabrication and characterization of a new photo-patternable hybrid organic-inorganic glass sol-gel and polymer materials for the realisation of integrated optic and opto-electronic devices. They exhibit low losses in the NIR range, especially at the most important wavelengths windows for optical communications (1320 nm and 1550 nm). The sol-gel and polymer process is based on photo polymerization and thermo polymerization effects to create the wave-guide. The single-layer film is at low temperature and deep UV-light is employed to make the wave-guide by means of the well-known photolithography process. Like any photo-imaging process, the UV energy should exceed the threshold energy of chemical bonds in the photoactive component of hybrid glass material to form the expected integrated optic pattern with excellent line width control and vertical sidewalls. To achieve optical wave-guide, a refractive index difference Delta n occurred between the isolated (guiding layer) and the surrounding region (buffer and cladding). Accordingly, the refractive index emerges as a fundamental device performance material parameter and it is investigated using slab wave-guide. (Abstract shortened by UMI.)

  16. Debonding/Delamination of Composites (Le Decollement et le Delaminage des Materiaux Composites)

    DTIC Science & Technology

    1992-12-01

    Delamination Onset in Composite Tensile Coupons," M S Thesis, Department of Civil Engineenng, the Ohio State3. Harris , A. and Orringer, 0...P in the vicinity of t2 be described by t - (I will be used in the sequel. exp(-a)(o< < 1, 0<a<n). The complex poter - .. i W can then be put in the

  17. Comment preparer des materiaux destines aux nouveaux lecteurs (How To Prepare Materials Intended for New Readers).

    ERIC Educational Resources Information Center

    Benson, Susan; And Others

    A French version of a guide originally published in Spanish for use in Latin America, this book explains how to develop instructional material for teaching reading to "new readers" in developing nations. The guide was developed to aid the teaching of reading to adults who can already read but who are not yet accomplished readers. The materials…

  18. Composability in quantum cryptography

    NASA Astrophysics Data System (ADS)

    Müller-Quade, Jörn; Renner, Renato

    2009-08-01

    If we combine two secure cryptographic systems, is the resulting system still secure? Answering this question is highly nontrivial and has recently sparked a considerable research effort, in particular, in the area of classical cryptography. A central insight was that the answer to the question is yes, but only within a well-specified composability framework and for carefully chosen security definitions. In this article, we review several aspects of composability in the context of quantum cryptography. The first part is devoted to key distribution. We discuss the security criteria that a quantum key distribution (QKD) protocol must fulfill to allow its safe use within a larger security application (e.g. for secure message transmission); and we demonstrate—by an explicit example—what can go wrong if conventional (non-composable) security definitions are used. Finally, to illustrate the practical use of composability, we show how to generate a continuous key stream by sequentially composing rounds of a QKD protocol. In the second part, we take a more general point of view, which is necessary for the study of cryptographic situations involving, for example, mutually distrustful parties. We explain the universal composability (UC) framework and state the composition theorem that guarantees that secure protocols can securely be composed to larger applications. We focus on the secure composition of quantum protocols into unconditionally secure classical protocols. However, the resulting security definition is so strict that some tasks become impossible without additional security assumptions. Quantum bit commitment is impossible in the UC framework even with mere computational security. Similar problems arise in the quantum bounded storage model and we observe a trade-off between the UC and the use of the weakest possible security assumptions.

  19. PREFACE 2nd International Conference on Materials Physics and Applications (JIPMA 2009/MATERIAUX 2009)

    NASA Astrophysics Data System (ADS)

    Cheikhrouhou, Abdelwaheb

    2010-11-01

    The 'Tunisian Materials Research Society: Tu-MRS' organized the International Days on Materials Physics and Applications 'JIPMA 2009' and the National Conference on Materials 'MATERIAUX 2009' in Gafsa (Tunisia) During the period 20-24 December 2009. The first International Days on Materials Physics and Applications 'JIPMA 2007' were organized in Annaba (Algeria) in November 2007 while the first National Conference on Materials 'MATERIAUX 2006' was organized in Douz (Tunisia) in December 2006. The 'JIPMA' conference series together with the 'MATERIAUX' intend to provide an excellent opportunity for international, Maghreb and Tunisian researchers to make their own works on materials known to a wider audience and to have discussions with other participants. This conference will also be an opportunity to exchange experiences, create and consolidate cooperation between different research structures in the Maghreb countries. This conference will equally promote research development, contribute to collaboration between universities and the socio-economical milieu. More than 300 senior researchers, Professors, PhD and Master students attended this conference from Tunisia, Algeria, Morocco, France, and Spain. Several researchers, engineers and managers from industrial firms also attended this scientific meeting. The conference consists of plenary and semi-plenary talks, oral contributions and poster presentations. The topics of the conference are: Nano-materials, nano-systems, thin films, surfaces and interfaces Multifonctional Materials, Magnetic Materials, Dielectric Materials, Superconducting Materials, Applications, ... Materials for Electronics, Informatics and Communications (Semi-conducting Materials, Electronic devices, Spintronic, ... Optoelectronic Materials, Sensors Ceramics, Glasses, Polymers, ... Natural Materials: Phosphates, Clay, ... Metallic Materials, alloys, ... Materials and Environment Materials and Energy Biomaterials Elaborating Methods and

  20. Composing decoherence functionals

    NASA Astrophysics Data System (ADS)

    Boës, Paul; Navascués, Miguel

    2017-02-01

    Quantum measure theory (QMT) is a generalization of quantum theory where physical predictions are computed from a matrix known as the decoherence functional (DF). Previous works have noted that, in its original formulation, QMT exhibits a problem with composability, since the composition of two decoherence functionals is, in general, not a valid decoherence functional. This does not occur when the DFs in question happen to be positive semidefinite (a condition known as strong positivity). In this paper, we study the concept of composability of DFs and its consequences for QMT. Firstly, we show that the problem of composability is much deeper than originally envisaged, since, for any n , there exists a DF that can coexist with n -1 copies of itself, but not with n . Secondly, we prove that the set of strongly positive DFs cannot be enlarged while remaining closed under composition. Furthermore, any closed set of DFs containing all quantum DFs can only contain strongly positive DFs.

  1. Applications of Composite Materials in Helicopter Construction (Les Applications des Materiaux Composite dans la Construction des Helicopteres),

    DTIC Science & Technology

    1983-11-21

    developments. Besides the weight savings obtained by the use of composite materials, it is appropriate to stress the reliability, the resistance to corrosion...molding Assembly by gluing and "ultrasonic" welding or resistance welding Price Ratio 1 4 2 Advantages No risk of corrosion Weight slightly Weight...all-composite cabin floor in place of the metal sandwich construction of DAUPHIN N. Bending strength Shear resistance Better ball impact strength

  2. Decomposing Composing Conventions.

    ERIC Educational Resources Information Center

    Beers, Terry

    Recent research has invited critiques of the authoritative descriptions of composing found in many rhetoric textbooks. The concept of "convention" may be especially useful in rethinking the teleological basis of these textbook descriptions. Conventions found in composition textbooks need to be unmasked as arbitrary concepts which serve…

  3. Composing and Comprehending.

    ERIC Educational Resources Information Center

    Jensen, Julie M., Ed.

    Intended for elementary school teachers of reading and composition, this book assembles several articles on the reading/writing relationship that have appeared in 1982 and 1983 issues of the journal "Language Arts." The three sections of the book define the relationship between composing and comprehending, explore relevant research, and…

  4. Les effets des interfaces sur les proprietes magnetiques et de transport des multicouches nickel/iron et cobalt/silver

    NASA Astrophysics Data System (ADS)

    Veres, Teodor

    Cette these est consacree a l'etude de l'evolution structurale des proprietes magnetiques et de transport des multicouches Ni/Fe et nanostructures a base de Co et de l'Ag. Dans une premiere partie, essentiellement bibliographique, nous introduisons quelques concepts de base relies aux proprietes magnetiques et de transport des multicouches metalliques. Ensuite, nous presentons une breve description des methodes d'analyse des resultats. La deuxieme partie est consacree a l'etude des proprietes magnetiques et de transport des multicouches ferromagnetiques/ferromagnetiques Ni/Fe. Nous montrerons qu'une interpretation coherente de ces proprietes necessite la prise en consideration des effets des interfaces. Nous nous attacherons a mettre en evidence, a evaluer et a etudier les effets de ces interfaces ainsi que leur evolution, et ce, suite a des traitements thermiques tel que le depot a temperature elevee et l'irradiation ionique. Les analyses correlees de la structure et de la magnetoresistance nous permettront d'emettre des conclusions sur l'influence des couches tampons entre l'interface et le substrat ainsi qu'entre les couches elles-memes sur le comportement magnetique des couches F/F. La troisieme partie est consacree aux systemes a Magneto-Resistance Geante (MRG) a base de Co et Ag. Nous allons etudier l'evolution de la microstructure suite a l'irradiation avec des ions Si+ ayant une energie de 1 MeV, ainsi que les effets de ces changements sur le comportement magnetique. Cette partie debutera par l'analyse des proprietes d'une multicouche hybride, intermediaire entre les multicouches et les materiaux granulaires. Nous analyserons a l'aide des mesures de diffraction, de relaxation superparamagnetique et de magnetoresistance, les evolutions structurales produites par l'irradiation ionique. Nous etablirons des modeles qui nous aideront a interpreter les resultats pour une serie des multicouches qui couvrent un large eventail de differents comportements magnetiques

  5. Modelisation des emissions de particules microniques et nanometriques en usinage

    NASA Astrophysics Data System (ADS)

    Khettabi, Riad

    La mise en forme des pieces par usinage emet des particules, de tailles microscopiques et nanometriques, qui peuvent etre dangereuses pour la sante. Le but de ce travail est d'etudier les emissions de ces particules pour fins de prevention et reduction a la source. L'approche retenue est experimentale et theorique, aux deux echelles microscopique et macroscopique. Le travail commence par des essais permettant de determiner les influences du materiau, de l'outil et des parametres d'usinage sur les emissions de particules. E nsuite un nouveau parametre caracterisant les emissions, nomme Dust unit , est developpe et un modele predictif est propose. Ce modele est base sur une nouvelle theorie hybride qui integre les approches energetiques, tribologiques et deformation plastique, et inclut la geometrie de l'outil, les proprietes du materiau, les conditions de coupe et la segmentation des copeaux. Il ete valide au tournage sur quatre materiaux: A16061-T6, AISI1018, AISI4140 et fonte grise.

  6. Process of timbral composing

    NASA Astrophysics Data System (ADS)

    Withrow, Sam

    In this paper, I discuss the techniques and processes of timbral organization I developed while writing my chamber work, Afterimage. I compare my techniques with illustrative examples by other composers to place my work in historical context. I examine three elements of my composition process. The first is the process of indexing and cataloging basic sonic materials. The second consists of the techniques and mechanics of manipulating and assembling these collections into larger scale phrases, textures, and overall form in a musical work. The third element is the more elusive, and often extra-musical, source of inspiration and motivation. The evocative power of tone color is both immediately evident yet difficult to explain. What is timbre? This question cannot be answered solely in scientific terms; subjective factors affect our perception of it.

  7. Hazard Studies for Solid Propellant Rocket Motors (Etude des Risque pour les Moteurs-Fusees a Propergols Solides)

    DTIC Science & Technology

    1990-09-01

    iss"ues de certaines elutdes ri~certes sut Ic comnportemnent des materiaux 6crgctiques. lii~’Urco-elcrecurqui i6iodie les pliuimrniues (IC r6icion... Resistivity Measurements as Applied to ESI) 108 .6.2 Dielectric Breakdown (dE. dt) III 5.0.3 Dielecttic Constant Measurements 112i 5.6.A The RC...required velocity and to overcome air resistance and gravity. In this context, the term "missile" is limited to self-propelled weapons and restricted to

  8. Composing Disability: Diagnosis, Interrupted.

    PubMed

    Wilkerson, Abby; Fisher, Joseph; Fletcher, Wade

    2016-12-01

    Writing is central both to the medical diagnostic codification of disability and to disabled people's efforts to interrupt, complicate, or disrupt dominant medical narratives. This Symposium, like the George Washington University conference from which it takes its name, creates space for diverse modes and genres of claiming authority regarding diagnosis and its cultural and material effects. "Queer" and "crip" interrogations of diagnosis illuminate its status as a cultural phenomenon, embracing culturally disavowed embodiments and embodied experiences as tools for diagnosing inegalitarian social relations and opportunities for cultural interventions. This Symposium traces the workings of diagnostic normativity manifested in experiences such as "disruptive deafness," unstable bodily materialities, pathologized grief and other forms of affective distress, and "surgical assemblages." It presents a diverse array of compositions, articulated on each writer's own terms, addressing a range of embodied experiences through multiple genres and voices, ranging from conversation transcript to scholarly essay, poetry, graphic memoir, and personal essay. Here, laypersons interrupt monologic medical diagnosis, claiming space to compose themselves. Together, the authors trace instances of corporeal "correction" back to the noxious agents, both environmental and political, that consistently breach the boundaries of corporeality.

  9. Teaching Composing with an Identity as a Teacher-Composer

    ERIC Educational Resources Information Center

    Francis, Jennie

    2012-01-01

    I enjoy composing and feel able to write songs that I like and which feel significant to me. This has not always been the case and the change had nothing to do with my school education or my degree. Composing at secondary school did not move beyond Bach and Handel pastiche. I did not take any composing courses during my degree. What did influence…

  10. Composing the Curriculum: Teacher Identity

    ERIC Educational Resources Information Center

    Lewis, Rebecca

    2012-01-01

    What is composing and how is it valued? What does a good education in composing look like; what constraints hinder it and is it possible to overcome such constraints? Can composing be a personal, creative and valuable activity for the school student? What role does the teacher play in all of this? These are questions that I discuss in this…

  11. Simulation de l'accretion de glace sur un obstacle bidimensionnel par la methode des bissectrices et par la modelisation des ruisselets et des gouttes de surface

    NASA Astrophysics Data System (ADS)

    Fortin, Guy

    Le LIMA (Laboratoire International des Materiaux Antigivre) en collaboration avec le CIRA (Italian Aerospace Research Centre) a developpe un logiciel simulant l'accretion de la glace en regimes sec et humide sur un objet bidimensionnel fixe. L'approche utilisee s'appuie sur les travaux de Lozowski pour les bilans energetiques, sur une etude du comportement du film d'eau, des ruisselets et des gouttes de surface pour le calcul des rugosites et des masses d'eau residuelle, ainsi que sur une methode de bissectrice pour l'evolution de la surface de glace. La contribution du CIRA a ete de fournir le logiciel pour le calcul des ecoulements et de la captation. Le bilan energetique base sur la conservation de l'energie est la sommation de la chaleur latente de fusion, d'evaporation et de sublimation, du rechauffement adiabatique et cinetique, et des pertes de chaleur par convection et conduction, ainsi que de l'evolution thermodynamique de l'eau de son etat initial a son etat final. La densite de la glace, qui a un impact important sur la simulation, est calculee a partir d'une correlation empirique developpee avec les cylindres tournants. En se basant sur les travaux de Al-Khalil et Hansman, le comportement des gouttes en regimes sec et humide a ete decrit analytiquement, ce qui a mene a determiner la hauteur maximale que peuvent atteindre les gouttes avant mouvement. Cette hauteur, appelee hauteur de mouvement, permet de determiner l'etat de l'eau sur la surface (film, ruisselets ou gouttes), ainsi que la hauteur des rugosites lorsque l'eau existe sous forme de gouttes ou de ruisselets. La hauteur de mouvement est determinee par l'equilibre entre les forces de cisaillement, induites par les effets aerodynamiques et gravitationnels evalues pour une goutte non deformee, et la force de cisaillement, induite par la tension de surface et la deformation de la goutte. Elle a ete validee en laboratoire et la precision obtenue pour la partie aerodynamique et gravitationnelle est

  12. Developpement d'un compresseur d'hydrogene base sur le cyclage thermique des hydrures metalliques

    NASA Astrophysics Data System (ADS)

    Laurencelle, Francois

    La compression de l'hydrogene est une etape incontournable de son utilisation dans l'industrie actuelle et dans les nouvelles applications energetiques de l'hydrogene (stockage stationnaire et transport). Les compresseurs mecaniques traditionnellement utilises posent plusieurs problemes d'ingenierie, de securite et de maintenance qui pourraient etre contournes en developpant de nouvelles technologies mieux adaptees a l'hydrogene. Dans cette these, notre objectif est de developper d'un compresseur d'hydrogene base sur les hydrures metalliques pouvant etre connecte a la sortie d'un electrolyseur fonctionnant a basse pression et d'ainsi repondre au besoin de productioncompression d'hydrogene decentralisee. La methodologie du projet comprend plusieurs etapes. Premierement, nous faisons la revue bibliographique des projets impliquant des compresseurs a hydrures metalliques. Deuxiemement, a travers des travaux experimentaux, nous recherchons des hydrures permettant une compression efficace entre 20 et 80°C. Les materiaux sont synthetises par fusion a arc electrique et caracterises sur bancs d'essais d'hydrogenation. La structure de certains materiaux est aussi investiguee par rayons X, methode de B.E.T. et microscopie electronique. Troisiemement, un reacteur d'hydrures est concu de maniere a promouvoir des echanges de chaleur rapides et efficaces. Quatriemement, le prototype et son interface de controle sont construits. Cinquiemement, le compresseur est caracterise pour en evaluer les performances en termes de debit et de capacite. Les resultats obtenus sont presentes dans trois articles publies et dans le chapitre 5 de cette these. Le compresseur (article I) est base sur trois hydrures (LaNi 4.8Sn0.2, LaNi5 et MMNi4.7Al0.3 ). Celui-ci permet d'atteindre un debit de compression de 10 a 20 L d'hydrogene par heure et son efficacite est, estimee a ˜5% par rapport a un compresseur adiabatique ideal. Il a ete demontre que l'efficacite pourrait etre augmentee en utilisant un

  13. AGARD Highlights 90/2. Part 2

    DTIC Science & Technology

    1990-09-01

    materiaux , des composants ponents, computer integrated manufac- 6lectroniques, de la productique, etc. turing, etc. Autre exemple, c’est au sein du Another...rdsistance des Right from the start, the resistance mat6riaux et des structures constituait of materials and structures was one of the un domaine...tests and tance des mat6riaux et des structures, resistance tests for materials and ainsi que les 6preuves devenues clas- structures, the lightning

  14. Etude des effets du martelage repetitif sur les contraintes residuelles

    NASA Astrophysics Data System (ADS)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  15. Characterisation of Fibre Reinforced Titanium Matrix Composites. (La Caracterisation des Materiaux Composites a Matrice de Titane Renforces par Fibres)

    DTIC Science & Technology

    1994-02-01

    fabrication of thick varying stages of preform walled rings. development, or are developed for reduction of fiber movement during Whereas the originally ...compressor in the original consortium were: components or hypervelocity plane structural components. These are characteristically high Harwell Laboratory...allows a larger for which the main loading originates from the number of single fibre ruptures before the composite centrifugal forces due to the high

  16. Short-Crack Growth Behaviour in Various Aircraft Materials (Le Developpement des Petites Fissures dans Divers Materiaux Aeronautiques)

    DTIC Science & Technology

    1990-08-01

    2024 aluminun AGARD Core Test Program. This aluminum-lithium material’s resistance to crack initiation and subsequent fast crack growth resulted in...boundaries did not seem to offer any resistance to crack propagation. This would be consistent with a sheet which is textured such that preferred slip...Regime to Overall Fatigue Resistance , Small Fatigue Cracks, R. 0. Ritchie and J. Lankford, eds., The Metallurgical Society, 1986, pp. 73-95 4 Edwards

  17. Etude de la performance de piles a combustible microbiennes et l'effet des materiaux d'electrodes

    NASA Astrophysics Data System (ADS)

    Martin, Edith

    Recent climate change has brought a whole new dimension to the energy field since now we must change our primary source, fossil fuels. The microbial fuel cell (MFC) technology emerged as a result of recent efforts in the development of alternative sources of energy. This project aims to improve the performance maximization of such celsl. It is assumed that the microbial fuel cells' functioning is influenced by the operation conditions as well as the biofilm development and other limitations. It is also appropriate to suppose that the electrode materials also have consequences on either the microorganisms' activity or the electrochemical reaction reactivity. Thus, various operating conditions and configurations are tested to identify the specific effects of these changes on cell performance. Also, the development of the biofilm is extensively studied under various conditions to improve the electrons transfer between the active biofilm and the anode. These experiments and analyses permitted to identify various effects that can improve the microbial fuel cell performance. Thus, the influence of organic load (of glucose and acetate), pH and operating temperature of the fuel cell has been shown and optimal values were determined, leading to a significant increase in the anodic biofilm activity and a decrease of the methanogens activity, the latter reducing the coulombic efficiency by diverting a non-negligible substrate amount for their benefit. Hence, organic loading of 2 to 4 g L-1 day-1, pH between 6,25 and 6,5 as well as high cathode temperature (62 °C) but moderate anode temperature (30 °C) caused a maximum power generation increase to 19,2 W m -3. During the experiments with acetate as substrate, distance between electrodes and fuel cell volume have been reduced, leading to a power density of 92,4 W m-3. All these observations are the subject of the first article presented in this thesis. Since the microbial fuel cell power generation depends on the number of anode-reducing microorganisms populating the biofilm, this relationship was deepened in the second manuscript. This article, which intended to monitor the biofilm development, highlights the influence of external load changing rate during the active biofilm growth. Thus, when the external load is adjusted rapidly to approach the cell internal resistance, electrons exchange is enhanced as well as the proliferation of microorganisms responsible of these electrons generation. By promoting faster anode-reducing microorganisms growth, other species are somewhat disadvantaged and substrate consumption is primarily involved in the electricity production rather than any other unwanted products (eg.: methane). This article also demonstrates the influence of the biofilm development level on the diffusion limitation of the anodic reaction, a limitation that becomes more pronounced as the biofilm grows. The third article clarifies the diffusion limitation of the charge transfer at the anode. Therefore, the organic load variation of acetate in microbial fuel cells with carbon felt (3D) and carbon paper (2D) anodes as well as the electrolyte conductivity decrease has targeted protons diffusion out of the biofilm as the current generation limitation. In addition, a secondary electrochemical reaction has been identified at the anode, creating an electrode resistance increase and thereby a slight power output decrease. Finally, multiple electrochemical analyses helped to establish with certainty that the electron transfer mechanism carried out by anode-reducing microorganisms is by direct contact with the anode via microorganisms themselves or the conductive biofilm matrix, cytochromes being responsible for the electrons transport in both cases. The last manuscript deals with new cathode materials (carbon, Mn 2O3 and Fe2O3) evaluation in comparison to a platinum cathode. These materials were chosen for their potential to stimulate the proliferation of microorganisms capable of influencing cathode activity in order to obtain a biocathode; however, this phenomenon has not been verified. (Abstract shortened by UMI.)

  18. Effet de l'usinage sur les proprietes mecaniques en tension et controle non-destructif des materiaux composites

    NASA Astrophysics Data System (ADS)

    Genereux, Louis-Alexandre

    The main goal of this work is to evaluate the impact of milling operations on the integrity of unidirectional carbon/epoxy laminate. Milling, often used for finishing composite structures, cause some damage in the form of craters, cracks and thermal damage to the matrix. Here, two approaches are used to qualify and quantify the amount of damage. First, two nondestructive testing methods, namely immersion ultrasonic inspection and pulsed thermography, are evaluated on samples with artificial defects. These techniques are then used on machined samples with realistic machining damages. Only ultrasounds allowed the detection and quantification of the machining damages, but only if the damages are at the surface of the laminate. The depth of damage depends primarily on the fiber orientation of the first ply with respect to the cutting direction. The ultrasonic inspections are also accompanied by scanning electron microscope observations. The second approach is to check whether the presence of the machining damage will affect the mechanical properties of the laminate. To do this, static tensile tests are performed on samples prepared by three different methods, namely, by abrasive diamond saw, by saw cut followed by sanding and finally by milling. The results show that the damages caused by the milling operation are not important enough to affect the ultimate stress and elastic modulus. Despite this, it would be interesting, for future works, to investigate this aspect in fatigue rather than with static tests. The presence of damages on the edge might promote delamination during cyclic loads.

  19. Vers le calcul efficace des propriétés effectives de materiaux microstructurés

    NASA Astrophysics Data System (ADS)

    Kreiner, Carl-Friedrich; Zimmer, Johannes; Chenchiah, Isaac V.

    2004-03-01

    An algorithm for partially relaxing multiwell energy densities, such as for materials undergoing martensitic phase transitions, is presented here. The detection of the rank-one convex hull, which describes effective properties of such materials, is carried out for the most prominent nontrivial case, namely the so-called Tk-configurations. Despite the fact that the computation of relaxed energies (and with it effective properties) is inherently unstable, we show that the detection of these hulls ( T4-configurations) can be carried out exactly and with high efficiency. This allows in practice for their computation to arbitrary precision. In particular, our approach to detect these hulls is not based on any approximation or grid-like discretization. This makes the approach very different from previous (unstable and computationally expensive) algorithms for the computation of rank-one convex hulls or sequential-lamination algorithms for the simulation of martensitic microstructure. It can be used to improve these algorithms. In cases where there is a strict separation of length scales, these ideas can be integrated at a sub-grid level to macroscopic finite-element computations. The algorithm presented here enables, for the first time, large numbers of tests for T4-configurations. Stochastic experiments in several space dimensions are reported here. To cite this article: C.-F. Kreiner et al., C. R. Mecanique 332 (2004).

  20. Recuperation d'energie issue des deformations de structures aeronautiques a l'aide de materiaux piezoelectriques

    NASA Astrophysics Data System (ADS)

    Debeaux, Sebastien

    Aerospace structural maintenance (fuselage, wings) is a major component of operational costs which requires aircraft to be grounded and some of its parts to be dismantled in order to proceed to inspection. In order to allow in situ monitoring, Structural Health Monitoring (SHM) has been proposed where sensors and actuators are integrated on the structure. To avoid extensive wiring of the nodes, wireless sensors and actuators are attractive but should be self powered to fully benefit from them. One idea is to convert the mechanical energy (vibrations) available all over an aircraft into electricity using piezoelectric materials. This work investigates the potential of strain-based energy harvesters (as opposed to inertial harvesters) to supply wireless nodes on typical aircraft structures. A simple model is used to describe typical dynamic behavior of aircraft components: a beam representing the whole wing subjected to aerodynamic loading and a plate representing a fuselage panel subjected to pressure fields (jet noise and turbulent boundary layer). Various configurations of piezoelectric materials are tested such as bulk PZT, PZT fiber composite and Polyvinylidene Fluoride (PVDF) in order to evaluate the influence of their characteristics (size, polarization, electrodes' shape, capacitance...) on the harvested power. The results show that for a typical aerospace excitation of the beam (10 Hz and 56 μdef), the energy produced is up to 40 mJ with bulk PZT for a 7 minutes loading time. From the literature, this appears sufficient for RF transmission (25 μJ). For other excitation sources (for instance jet noise), the energy produced is up to only 1 mJ with bulk PZT for a 25 minutes loading time. The drawback is that we should wait for several seconds in order to charge the harvester's battery. And, considering that many other components than the RF transceiver will require energy in the meantime, the time laps between two' measures could increase to several minutes. Therefore, strain-based energy harvester could be used for supplying wireless sensor nodes but they would not allow real time measurement. However this approach is a simple and convenient way to scavenge energy compared to other kinds of harvesters (inertial, solar...) since it amounts to bonding a piezoelectric material on a flexible surface. Some design advices are eventually proposed for this kind of harvesters. They could be used for designing a harvester able to produce desired power from a known excitation. Keywords: Power harvesting, piezoelectric, piezoelectric fiber composite, vibration energy, structural health monitoring.

  1. Contribution a l'etude du comportement de dalles de ponts en beton arme de barres en PRF soumises a des charges concentrees simulant les charges de roues

    NASA Astrophysics Data System (ADS)

    Bouguerra, Kheireddine

    Au cours des dernieres annees, la deterioration des structures en beton arme a pris une ampleur sans precedent, et ce, malgre le fait que leur duree de vie en service initialement prevue est loin d'etre atteinte. La corrosion de l'armature d'acier est un des principaux facteurs reduisant la duree de vie des ponts en beton arme d'acier. Par ailleurs, l'armature en materiaux composites de polymeres renforces de fibres (PRF) constitue une solution a l'armature metallique afin de pallier au probleme de la corrosion d'acier et a la deterioration des structures en beton arme. Aussi, les barres d'armature en materiaux composites de PRF possedent une resistance en traction elevee (environ 2 a 6 fois la limite elastique de l'acier d'armature conventionnel), ce qui leur permet de constituer un renforcement structural attrayant pour les structures en beton. Le comportement d'elements structuraux en beton arme de barres en PRF est different de ceux en beton arme de barres d'acier. En effet, les barres en PRF possedent un module d'elasticite relativement plus faible que celui de l'acier et ont des proprietes d'adherence differentes de celles des barres d'acier. L'utilisation des barres d'armature en PRF pour armer les dalles de tabliers de ponts se concretise de plus en plus avec l'avancement des recherches dans ce domaine. La recherche entamee dans le cadre de cette these s'inscrit dans un programme de travaux realises au sein de la Chaire de recherche CRSNG/Industrie sur les Materiaux composites novateurs en PRF pour les infrastructures au departement de genie civil a l'Universite de Sherbrooke. Le comportement de membrures en beton arme de PRF soumis a des sollicitations mecaniques constitue un des principaux axes de recherche. Dans le cadre de cette these, une serie d'essais a ete effectuee sur huit dalles de ponts a confinement interne a grande echelle. Les parametres des essais comprennent: (1) l'epaisseur de la dalle, (2) le type et le taux d'armature transversale de l

  2. Guidelines for Coaching Student Composers.

    ERIC Educational Resources Information Center

    Wilson, Dana

    2001-01-01

    Focuses on teaching students how to compose music. Addresses issues, such as how to get the students started and types of questions to ask students about their compositions. Discusses the musical elements involved in composition, such as melody, harmony, rhythm and meter, timbre, texture, and formal design. (CMK)

  3. Prise en compte des conditions des materiaux et du couplage axial le long d'un canal du reacteur refroidi a eau supercritique canadien

    NASA Astrophysics Data System (ADS)

    Harrisson, Genevieve

    This research project has established a simulation strategy capable of taking into account the conditions of the materials and the axial coupling along a fuel channel of the Canadian Supercritical-Water-Cooled Reactor (SCWR). The proposed simulation strategy solves the transport equation for the complete channel defined in exact geometry without having to make three-dimensional calculation. The proposed simulation strategy consists of making a series of two-dimensional lattice cell calculations followed by a one-dimensional slab geometry calculation. It has been shown that the proposed simulation strategy is equivalent to a three-dimensional channel calculation within reasonable limits. For this demonstration, SERPENT 1.1.16 is used to perform the three-dimensional channel calculations and the two-dimensional lattice cell calculations while DRAGON 3.06 is used to perform the one-dimensional slab geometry calculations. From three-dimensional complete and partial channels with axial reflector, this research project has assessed the impact of the axial reflector on the channel neutronic properties and inversely, the impact of the fuel planes on the axial reflector neutronic properties. It was observed that the axial reflector affects mainly the neutronic properties of the fuel planes adjacent to the axial reflector and that the accuracy of the axial reflector neutronic properties increases as the number of fuel planes in the partial channels increases. In the second part, this research project has demonstrated the applicability of the proposed simulation strategy in the calculation chain conventionally used in neutronics and has evaluated its impact on the SCWR core neutronic properties. To do this, the proposed simulation strategy was entirely modeled using DRAGON 3.06 and the complete SCWR core was modeled with DONJON 3.02. Four models of reactor database were developed. The model of the isolated unit cell uses only one unit cell and changes only the fuel composition over time. The model of the fourteen isolated unit cells takes into account the conditions of the materials along the channel. The models of the fourteen coupled unit cells take into account the conditions of the materials and the axial coupling along the channel by implementing the proposed simulation strategy. In the case named in continue, the power profile along the channel used in burnup calculations remains constant while in the case named in alternation, this profile depends on the properties of the one-dimensional channel over time. The core calculations made in this research project are very simple. They limited themselves to fill the initial core with fresh fuel, to burn the fuel, to refuel the core when necessary and to follow the core neutronic properties during the cycles. Finally, it is advantageous to consider the fuel channel as the motive in the SCWR core because it allows to better take into account the physics of the problem. It has been shown that the conditions of the materials along the channel have a significant impact on the core neutronic properties. Hence, we advise against the use of the model of the isolated unit cell. The axial coupling along the channel is present, but its impact on the core neutronic properties is very light. Therefore, we recommend the use of the model of the fourteen isolated unit cells when several transport calculations are required and the use of the model of the fourteen unit cells coupled in continue in a punctual manner in order to assess the importance of the axial coupling as the core design gradually evolves. For the moment, we do not recommend the use of the model of the fourteen unit cells coupled in alternation because it should be studied further before being used.

  4. Organists and organ music composers.

    PubMed

    Foerch, Christian; Hennerici, Michael G

    2015-01-01

    Clinical case reports of patients with exceptional musical talent and education provide clues as to how the brain processes musical ability and aptitude. In this chapter, selected examples from famous and unknown organ players/composers are presented to demonstrate the complexity of modified musical performances as well as the capacities of the brain to preserve artistic abilities: both authors are active organists and academic neurologists with strong clinical experience, practice, and knowledge about the challenges to play such an outstanding instrument and share their interest to explore potentially instrument-related phenomena of brain modulation in specific transient or permanent impairments. We concentrate on the sites of lesions, suggested pathophysiology, separate positive (e.g., seizures, visual or auditory hallucinations, or synesthesia [an involuntary perception produced by stimulation of another sense]) and negative phenomena (e.g., amusia, aphasia, neglect, or sensory-motor deficits) and particularly address aspects of recent concepts of temporary and permanent network disorders.

  5. Etude du stockage de l'hydrogene sur des nanostructures de carbone microporeuses

    NASA Astrophysics Data System (ADS)

    Poirier, Eric

    2007-12-01

    Le stockage de l'hydrogene par adsorption sur des adsorbants nano-structures a ete etudie sous differentes conditions de pression et de temperature. Les adsorbants etudies sont principalement des nanotubes de carbone a simple paroi ainsi que des structures metallo-organiques. Les mesures ont ete realisees a l'aide de systemes gravimetriques et volumetriques tres sensibles specialement mis au point pour de petits echantillons necessitant un degazage in situ. Les appareils developpes, au nombre de quatre, comprennent deux systemes gravimetriques et deux systemes volumetriques. Ensemble, ces systemes couvrent la plage de pressions (0-100) bars ainsi que la plage de temperatures (77-295) K. Les differentes analyses montrent que l'adsorption d'hydrogene sur les adsorbants nano-structures etudies est maximale a 77 K et varie entre environ (1.5 et 4) % masse. A temperature ambiante, l'adsorption croit lineairement avec la pression et demeure sous les 1% masse pour des pressions inferieures a 100 bars. L'adsorption d'hydrogene sur ces materiaux dans ces conditions se compare notamment a celle obtenue sur des charbons actives. La modelisation de l'adsorption a egalement ete realisee dans des conditions cryogeniques a l'aide du modele de Dubinin-Astakhov sous une forme adaptee pour l'adsorption supercritique. Les enthalpies d'adsorption calculees a partir de ce modele varient sous les 6 kJ/mole et sont donc consistantes avec des processus de physisorption. L'applicabilite du modele de Dubinin-Astakhov suggere que l'adsorption d'hydrogene puisse etre representee par un processus de remplissage des pores par un pseudo-liquide. Ces travaux s'inscrivent dans un contexte ou la capacite d'adsorption reelle des nanostructures de carbone est sujette a la controverse. En consequence, l'approche experimentale adoptee se distingue par les differentes demarches mises de l'avant pour l'obtention de mesures fiables sur des echantillons de faibles masses ainsi que par son caractere

  6. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  7. Nurturing the Careers of Australia's Future Composers

    ERIC Educational Resources Information Center

    Watson, Amanda; Forrest, David

    2008-01-01

    In 1994, the Australian Society for Music Education (ASME) initiated two related projects supporting and acknowledging composition in schools and offering the opportunity for secondary school-aged students to work with prominent Australian composers. These were the Young Composers' Project and the Composer-in-Residence Project. Both projects were…

  8. Sing the Songs of Women Composers.

    ERIC Educational Resources Information Center

    Allen, Sue Fay; Keenan-Takagi, Kathleen

    1992-01-01

    Presents an annotated listing of choral works by women composers. Suggests sources of information about women composers and their music. Discusses some contemporary women whose compositions are particularly appropriate for student voices. Concludes that the listed works will help place women composers in perspective for student choral groups. (SG)

  9. Preparing Students to Compose on a Computer.

    ERIC Educational Resources Information Center

    Gadomski, Kenneth E.

    In the proliferation of articles about using computers in the composition classroom published in the last five or ten years, few mention anything about preparing students to compose on a computer while all assert that computers do indeed help the composing process. Preparing students to compose on a computer involves three major processes:…

  10. The composing process in technical communication

    NASA Technical Reports Server (NTRS)

    Masse, R. E.

    1981-01-01

    The theory and application of the composing process in technical communications is addressed. The composing process of engineers, some implications for composing research for the teaching and research of technical communication, and an interpretation of the processes as creative experience are also discussed. Two areas of technical communications summarized concern: the rhetorical features of technical communications, and the theoretical background for a process-based view, a problem-solving approach to technical writing.

  11. America's Women Composers: Up from the Footnotes.

    ERIC Educational Resources Information Center

    Pool, Jeannie G.

    1979-01-01

    This article presents an overview on women composers in the United States from the eighteenth century to the present. It also lists women's musical organizations, selected references on women in music, and available recordings of works by American women composers. (SJL)

  12. Adolescents' Dialogic Composing with Mobile Phones

    ERIC Educational Resources Information Center

    Warner, Julie

    2016-01-01

    This 14-month study examined the phone-based composing practice of three adolescents. Given the centrality of mobile phones to youth culture, the researcher sought to create a description of the participants' composing practices with these devices. Focal participants were users of Twitter and Instagram, two social media platforms that are usually…

  13. A Virtual Composer in Every Classroom

    ERIC Educational Resources Information Center

    Hoffman, Adria R.; Carter, Bruce A.

    2013-01-01

    Previous generations applauded grant-funded programs that brought living composers into the lives of K-12 music students. The current economic climate, however, limits opportunities similar to those enjoyed in the past. We designed a virtual composer-in-residence experience that uses technology to overcome the barriers of funding limitations and…

  14. Children Composing and the Tonal Idiom

    ERIC Educational Resources Information Center

    Roels, Johanna Maria; Van Petegem, Peter

    2016-01-01

    Existing studies have demonstrated how children compose, experiment and use their imagination within the conventions of the tonal idiom with functional harmony. However, one area of research that has hardly been explored is how tonality emerges in the compositions of children who compose by transforming their own non-musical ideas, such as their…

  15. Research on BOM based composable modeling method

    NASA Astrophysics Data System (ADS)

    Zhang, Mingxin; He, Qiang; Gong, Jianxing

    2013-03-01

    Composable modeling method has been a research hotpot in the area of Modeling and Simulation for a long time. In order to increase the reuse and interoperability of BOM based model, this paper put forward a composable modeling method based on BOM, studied on the basic theory of composable modeling method based on BOM, designed a general structure of the coupled model based on BOM, and traversed the structure of atomic and coupled model based on BOM. At last, the paper introduced the process of BOM based composable modeling and made a conclusion on composable modeling method based on BOM. From the prototype we developed and accumulative model stocks, we found this method could increase the reuse and interoperability of models.

  16. Interdiffusion de puits quantiques controlee par irradiation laser excimere pour l'integration de composants photoniques

    NASA Astrophysics Data System (ADS)

    Genest, Jonathan

    L'integration de composants discrets sur un systeme unique, tel une puce electronique, augmente les performances totales du systeme, fait apparaitre de nouvelles fonctionnalites et diminue les couts associes a la fabrication des dispositifs. Ces ameliorations, appliquees au secteur de la microelectronique, sont grandement responsables des avancements importants qu'ont connus les technologies de l'information et des communications au cours des dernieres annees. Puisque la fabrication de circuits photoniques integres necessite l'integration de structures ayant des bandes interdites differentes a partir d'une meme puce semiconductrice, leur niveau d'integration est bien inferieur que celui atteint pour un microprocesseur standard. Parmi les techniques ayant le potentiel de fabriquer des circuits photoniques integres monolithiquement, l'interdiffusion de puits quantique post-expitaxial controlee spatialement augmente la bande interdite d'une heterostructure semiconductrice a l'interieur de regions definies. Le processus d'interdiffusion, active thermiquement, est accelere par la diffusion d'impuretes et de defauts ponctuels tels que les lacunes et les interstitiels. L'hypothese de depart de mes travaux de doctorat suppose que la radiation laser ultra-violette module la diffusion et la generation de defauts ponctuels dans les heterostructures reposant sur les technologies a base de GaAs et d'InP et, consequemment, controle spatialement l'interdiffusion de puits quantiques. Nous avons demontre que lorsque appliquee sur des heterostructures a base de GaAs, l'irradiation laser excimere l'interdiffusion en favorisant la croissance d'un stresseur de surface qui empeche la diffusion des defauts ponctuels vers les puits quantiques. Nous avons souligne l'influence de la vapeur d'eau physisorbee sur la croissance du stresseur et avons determine la resolution spatiale de la technique. Dans les heterostructures basees sur les technologies InP, meme sous le seuil d'ablation, l

  17. Modelisation de materiaux composites adaptatifs munis d'actionneurs en alliage a memoire de forme

    NASA Astrophysics Data System (ADS)

    Simoneau, Charles

    Technological development of structures having the capabilities to adapt themselves to different operating conditions is increasing in many areas of research such as aerospace. In fact, numerous works are now oriented toward the design of adaptive aircraft wings where the goal is to enhance the aerodynamic properties of the wing. Following this approach, the work realised in the framework of this master thesis presents the steps leading to the creation of a numerical model that can be used to predict the behavior of an adaptive panel, and therefore, eventually of an adaptive aircraft wing. Foremost, the adaptive panel of this project has been designed from a carbon-epoxy composite, acting as host structure, where shape memory alloy (SMA) wires, acting as actuators, have been inserted in it. SMA actuators have also been embedded asymmetrically along the direction of the panel thickness in order to generate a bending moment when the SMA wires are activated. To achieve the modeling of such structure it has been firstly shown that a numerical model composed of only solid finite elements could be used to represent the panel. However, a second numerical model composed of shell, beam and link finite elements showed that identical results can be obtained with much less nodes (the first model was composed of more than 300 000 nodes compared with 1 000 nodes for the second). The combination of shell-beam-link elements has then been chosen. Secondly, a constitutive relation had to be used for modeling the particular behavior of SMA. For the present work, a uniaxial version of the Likhachev's model is used. Due to its fairly straightforward mathematical formulation, this material law is able to model the main functional properties of SMA including the two-way shape memory effect (TWSME) at zero stress obtained after a thermomechanical education treatment. The last step was to compare the results of the numerical simulations with those obtained with a prototype where 19

  18. Music and emotion—a composer's perspective

    PubMed Central

    Douek, Joel

    2013-01-01

    This article takes an experiential and anecdotal look at the daily lives and work of film composers as creators of music. It endeavors to work backwards from what practitioners of the art and craft of music do instinctively or unconsciously, and try to shine a light on it as a conscious process. It examines the role of the film composer in his task to convey an often complex set of emotions, and communicate with an immediacy and universality that often sit outside of common language. Through the experiences of the author, as well as interviews with composer colleagues, this explores both concrete and abstract ways in which music can bring meaning and magic to words and images, and as an underscore to our daily lives. PMID:24348344

  19. Materiaux piézoélectriques pour moteurs ultrasonores performances requises et problèmes technologiques

    NASA Astrophysics Data System (ADS)

    Gonnard, P.; Eyraud, L.; Guillemot, M. M.

    1994-07-01

    For many years ultrasonic piezoelectric motors are the subject of a great number of papers and patents. The submitted structures yield a great variety of piezoceramics shapes, of the excitation mode and the applied electric fields. The main required properties of the active materials are presented on the basis of the figure of merit (coupling factor, electromechanical transformer ratio) and on the basis of losses and aging as well. The significant technological problems presented by some structures are analysed : reverse polarizations into a same ceramic, strong silkscreen printing, achievement of a strong, conductive and non absorbing, metal-ceramic bond,... At last an industrial outlet of piezoelectric motors will mainly depend on the upper cost limit of piezoceramics when built in great number. Such a cost will be bound to the required geometries and machining. Les moteurs piézoélectriques ultrasonores font depuis plusieurs années l'objet de très nombreuses publications et brevets. La diversité des structures proposées entraîne une grande variété des formes des céramiques piézoélectriques, de leur mode d'excitation et des champs électriques appliqués. Les principales performances requises des matériaux actifs sont présentées tant sur le plan des facteurs de mérites (facteur de couplage, rapport de transformation électromécanique, ... ) que sur celui des pertes ou du vieillissement. Les importants problèmes technologiques posés par certaines structures sont analysés : polarisations inversées dans une même céramique, sérigraphies résistantes, réalisation de liaisons céramiques-métal solides, conductrices et non amorties... Enfin le débouché industriel des moteurs piézoélectriques dépendra essentiellement du coût limite en fabrication de masse des éléments céramiques, piézoélectriques qui restera très lié aux géométries et aux usinages exigés.

  20. Research on Composing: Points of Departure.

    ERIC Educational Resources Information Center

    Cooper, Charles R., Ed.; Odell, Lee, Ed.

    While the chapters of this book present a variety of perspectives, they share the common goal of redirecting and revitalizing research on written composition. The authors review research on written discourse and the composing process and raise questions regarding information and skills that teachers and researchers need to consider. The chapters…

  1. The Composing Processes of Mature Adults.

    ERIC Educational Resources Information Center

    Crabbe, Katharyn

    The study examined 41 students (24 male, 17 female) in a beginning writing course for adults. Data were collected by (1) taping four workshop sessions in which all students participated in small groups, (2) interviewing all the students, and (3) observing four students writing in the classroom. The adult writers composed in two models: the…

  2. The Composer in the Liberal Arts College

    ERIC Educational Resources Information Center

    Schwartz, Elliott

    2011-01-01

    This essay explores the role of music composition within the curriculum of a typical small liberal arts college and the faculty composer's role(s) in facilitating the study of composition. The relationship between composition and campus performance is discussed, particularly in light of the increased emphasis on performance in formerly all-male…

  3. Composing Networks: Writing Practices on Mobile Devices

    ERIC Educational Resources Information Center

    Swarts, Jason

    2016-01-01

    This article is an investigation of composing practices through which people create networks with mobile phones. By looking through the lens of actor-network theory, the author portrays the networking activity of mobile phone users as translation, what Latour describes as an infralanguage to which different disciplinary perspectives can be…

  4. Composing Zen Haiku: Training to Make Sense.

    ERIC Educational Resources Information Center

    Holmes, Stewart W.

    1996-01-01

    Suggests that composing "haiku" requires a discipline in a person's thinking and emoting patterns similar to that of a general semantics system for training people to make sense. Describes how such haiku are written and gives some guidelines to help individuals create their own. (PA)

  5. The Composer's Blueprint: A Teacher's Guide.

    ERIC Educational Resources Information Center

    Trzcinski, Louis C.; Nelhybel, Vaclav

    This teacher's guide is designed to accompany two 15-minute color television programs dealing with the creative process involved in conceiving a composition. The programs are appropriate for junior high school string students and instrumental students in string methods courses at teacher training institutions. In the program, the composer explains…

  6. Enhancing Memory in Your Students: COMPOSE Yourself!

    ERIC Educational Resources Information Center

    Rotter, Kathleen M.

    2009-01-01

    The essence of teaching is, in fact, creating new memories for your students. The teacher's role is to help students store the correct information (memories) in ways that make recall and future access and use likely. Therefore, choosing techniques to enhance memory is possibly the most critical aspect of instructional design. COMPOSE is an acronym…

  7. Evaluation de l'effet de la temperature de cure sur le comportement des materiaux bitumineux de type mr-5 traites a la mousse de bitume

    NASA Astrophysics Data System (ADS)

    Cardenas, Jose Alberto

    Cold recycling mixes and cold mixes with RAP are used in Quebec since 1991. However, this practice is not recommended at temperatures below 10 ° C. Very little research on this subject and the effects of low temperatures on the behavior of early mixes are being done. The present study compares the behavior of a MR-5 mix under different cure temperature, 0 ° C, 5 ° C, 10 ° C, and 23 ° C as the reference temperature. The cold curing conditions are explained in details. The research is based on two main aspects: the effect of curing temperature on the cold recycling materials with foamed asphalt and the comparison between two methods of testing the mechanical properties, there are the Marshall stability and the Indirect Tensile Strenght ITS. The study is divided into three stages. The first stage is the optimization of the foam properties and the mix design of test. The second stage is to prepare the specimens of MR-5 MB and the storage on the predefined cure conditions. Finally, the third stage consists of mechanical strength testing of briquettes at the curing time appointed. Meanwhile, at each stage, we evaluate the associated parameters, which are little known and highly useful in road construction. Firstly, we assess the foam index and the surface of contraction, which is used for formulating and optimization of the foam bitumen mixes. Secondly, we evaluate the index of fracture (IF) and the ductility index (ID) associated with the mechanical strength. At the end of the project, we compare the resistance of the MR-5 foamed bitumen used in this research with the MR-5 bitumen emulsion. The latter is more used in the road industry in Quebec and serves as a reference for the comparison. Both tests show that there is an increase in the resistance of the materials with time, even at temperature below 10 ° C. We notice that the percentage of increase in the resistance of the materials is significantly different in both tests. However, the ITS is highly effective in cold mixes characterization and gives more details on the behavior of the MR-5 materials in different temperature.

  8. Optimisation structurale de dalles de chaussees en beton jointees avec des goujons en materiaux composites en Polymeres Renforces de Fibres de Verre (PRFV)

    NASA Astrophysics Data System (ADS)

    Bricola, Julien

    In Quebec, the majority of the road network was built in the 60's - 70's and show obvious signs of ageing. Moreover, the increase of road traffic and the rigorous weather conditions, render the maintenance and the exploitation of roads in this Northern American part quite difficult. Indeed, these environmental conditions cause severe damages for roads, especially in winter. The degradation factor of the jointed rigid pavement is intensified by the highway salt. So, the phenomena of deteriorations appears mainly by the corrosion of the steel at the joints (structural elements) guaranteeing the durability of roads. The jointed rigid pavements or "short jointed pavements" are still mainly sized with steel dowels placed at the lining of joints. One of the main functions of these structures is to control the formation of cracking due to the thermal and environmental conditions. In order to reduce these , disorders, the Ministry of Transport of Quebec (MTQ) turned towards new techniques and innovative materials to ensure the longevity of roads. With the rapid evolution of specific methods and knowledge in roads design, joined with technologies and new products, the MTQ emphasizes the research and development. That way, advanced techniques and diverse technologies in the Quebecois context are settled. As a matter of fact, one of the axes of these development researches concerns the composite materials which have recently been given good results in the civil engineering area. That is why Glass Fibre-Reinforced Polymer (GFRP) dowels bars appear as a solution to the steel corrosion. In fact, they provide better durability with lower costs: the increase of service life as well as the decrease of maintenance persons and traffics impac. Thus, this project proposes an optimization of structural design of GFRP dowels for transverse jointed highway pavement slabs, also keeping in mind their use in new projects. The GFRP dowels which are given in this essay are made by the Pultrall Inc. Company from Thetford Mines (Quebec, Canada). The resin used for the polymer materials is only vinylester resin and the dowels have diameters going from 28.6 mm to 34.9 mm. Finally, only a stiff base is used for the road, its particularity is the modulus of subgrade reaction. Keywords: concrete pavement, dowelled slab, jointed concrete pavement, GFRP dowels, optimization, structural, design .

  9. Active Noise and Vibration Control Literature Survey: Sensors and Actuators

    DTIC Science & Technology

    1999-08-01

    duire leur detectabilite done leur vulnerabilite a l’attaque ennemie. Le present rapport contient une etude approfondie des technologies des capteurs ...concentree sur une vaste gamme de materiaux de capteur et d’actionneur, tels que les materiaux piezoelectriques et electrostrictifs, les materiaux...l’air. On a etudie les technologies des capteurs et des actionneurs convenant a la limitation active du bruit se propageant par ces trajets (ou des

  10. Photonic Metamaterials for Defence and Security Applications (Les meta-materiaux photoniques pour les applications de defense et de securite)

    DTIC Science & Technology

    2008-04-01

    exceptionnelles qui ne sont pas facilement observables dans les matériaux naturels . La plupart des recherches sur les méta-matériaux ont été consacrées à...matériaux naturels ) est une des principales raisons qui a poussé les chercheurs à approfondir leurs études sur les méta-matériaux. Avec un index...rapports signal/bruit plus importants, une vitesse plus élevée, une taille réduite, et une gamme plus large pour les systèmes de capteurs optiques

  11. Concepts and Applications of Composable FORCEnet

    DTIC Science & Technology

    2005-12-01

    2080 WSEAS TRANS. on INFORMATION SCIENCE & APPLICATIONS Issue 12. Volume 2. December 2005 ISSN: 1790-0832 Concepts and Applications of Composable...STATEMENT A Approved for Public Release Distribution Unlimited 20060926075 WSEAS TRANS. on INFORMATION SCIENCE & APPLICATIONS Issue 12. Volume 2, December...information from one system or network to an- automatic insertion of content. The project team connects these data sources, views, and agents 2082 WSEAS

  12. Is the Higgs boson composed of neutrinos?

    DOE PAGES

    Krog, Jens; Hill, Christopher T.

    2015-11-09

    We show that conventional Higgs compositeness conditions can be achieved by the running of large Higgs-Yukawa couplings involving right-handed neutrinos that become active at ~1013–1014 GeV. Together with a somewhat enhanced quartic coupling arising by a Higgs portal interaction to a dark matter sector, we can obtain a Higgs boson composed of neutrinos. Furthermore, this is a “next-to-minimal” dynamical electroweak symmetry breaking scheme.

  13. Is the Higgs boson composed of neutrinos?

    SciTech Connect

    Krog, Jens; Hill, Christopher T.

    2015-11-09

    We show that conventional Higgs compositeness conditions can be achieved by the running of large Higgs-Yukawa couplings involving right-handed neutrinos that become active at ~1013–1014 GeV. Together with a somewhat enhanced quartic coupling arising by a Higgs portal interaction to a dark matter sector, we can obtain a Higgs boson composed of neutrinos. Furthermore, this is a “next-to-minimal” dynamical electroweak symmetry breaking scheme.

  14. [Mental disease in two classical music composers].

    PubMed

    Rempelakos, L; Poulakou-Rebelakou, E; Ploumpidis, D

    2012-01-01

    A study οn two neglected classical music composers suffering a not syphilitic mental disease, is attempted here, syphilis of the central nervous system being frequent in that time. A brief overview on the psychiatric ailments of many great composers reveals suicide attempts and more or less severe depression following external events. The issue of a possible relationship between mental disease and (musical) creativity can be discussed, as mood swings and a certain tendency to melancholia are frequent features of a talented brain (a fact that can also be detected in their works). The first case presented here is Hans Rott from Austria, the beloved student of Anton Bruckner, who was considered to be at least equal to his famous classmate Gustav Mahler. The great expectations of his teacher and his friends suddenly came to an end, when he suffered a crisis of schizophrenia and was hospitalized in an insane asylum in Lower Austria. The tragic psychiatric adventure of the young musician lasted almost four years. He was diagnosed as a case of "hallucinatory insanity" and "persecution mania" by the medical staff, before dying of tuberculosis, aged only 26, and having completed only one symphony and several smaller works. His name came again on surface only a century after his death, when in 1989 his Symphony in E Major was discovered and premiered with great success, permitting to its creator a posthumous recognition, among Bruckner and Mahler. The second case of mental illness is that of the Armenian Komitas Vardapet. He was an orphan who grew up in theological schools and became a monk and later a priest, though he spent some years in Berlin in order to develop his musical skills. He is considered to be an authority of Armenian ecclesiastic music, introducing polyphony in the Armenian Church's music and collecting numerous traditional songs from all parts of Armenia. In 1915, during the Armenian genocide he was deported, tortured but finally saved, due to interventions

  15. Composing Models of Geographic Physical Processes

    NASA Astrophysics Data System (ADS)

    Hofer, Barbara; Frank, Andrew U.

    Processes are central for geographic information science; yet geographic information systems (GIS) lack capabilities to represent process related information. A prerequisite to including processes in GIS software is a general method to describe geographic processes independently of application disciplines. This paper presents such a method, namely a process description language. The vocabulary of the process description language is derived formally from mathematical models. Physical processes in geography can be described in two equivalent languages: partial differential equations or partial difference equations, where the latter can be shown graphically and used as a method for application specialists to enter their process models. The vocabulary of the process description language comprises components for describing the general behavior of prototypical geographic physical processes. These process components can be composed by basic models of geographic physical processes, which is shown by means of an example.

  16. Annuaire du bureau des Longitudes : guide de données astronomiques 2012 pour l'observation du ciel

    NASA Astrophysics Data System (ADS)

    Institut de Mécanique Céleste Et de Calcul Des Ephémérides (Imcce); Bureau Des Longitudes (Bdl)

    2011-07-01

    Destiné aux astronomes, professionnels ou amateurs, cet ouvrage se décompose de la façon suivante : Les trois premiers chapitres de cet ouvrage contiennent : les données sur les différents calendriers et leur concordance, les fêtes légales en France, les différentes échelles de temps, les dates de décrets sur les heures légales en France métropolitaine parues au Journal Officiel depuis 1916 ; des notions nécessaires à la compréhension et à l'emploi des éphémérides contenues dans l'ouvrage. Les chapitres suivant fournissent des éphémérides astronomiques : les positions du Soleil et de la Lune ; les positions des planètes et de leurs satellites ; les positions des astéroïdes et des comètes ; les explications et des données pour l'observation de la surface du Soleil, de la Lune et des planètes ; des cartes du ciel, une liste de constellations et les positions et occultations des étoiles ; des données sur les éclipses de Soleil et de Lune et sur les phénomènes astronomiques ; la liste des observatoires astronomiques les plus connus.

  17. Hygrothermal Effects in Continuous Fibre Reinforced Composites. Part I. Thermal and Moisture Diffusion in Composite Materials (Effets Hygrothermiques dans les Composites a Renfort de Fibre Continu. Partie I. Diffusion de L’Humidite et de la Chaleur dans les Materiaux Composites)

    DTIC Science & Technology

    1983-01-01

    HYGROTHERMIQUES DANS LES COMPOSITES A RENFORT DE FIBRE CONTINU PARTIE I - DIFFUSION DE L’HUMIDITE ET DE LA CHALEUR DANS LES MATERIAUX COMPOSITES by/par J.P...structures for space- craft hardware)[223]. Composite materials are often subjected to fatigue loads and should exhibit impact strength and shock resistance

  18. Collision Tumor Composed of Meningioma and Cavernoma.

    PubMed

    Weigel, Jens; Neher, Markus; Schrey, Michael; Wünsch, Peter H; Steiner, Hans-Herbert

    2017-01-01

    A true collision tumor is a rare entity composed of two histologically distinct neoplasms coinciding in the same organ. This paper reports a unique case of cerebral collision tumor consisting of two benign components. On the first hand, meningioma which is usually a benign lesion arising from the meningothelial cell in the arachnoidal membrane. On the other, cerebral cavernoma which is a well-circumscribed, benign vascular hamartoma within the brain. To our knowledge, there is no previously documented case of cerebral collision tumor consisting of two benign components. A 56-year-old Caucasian male suffered in 2002 from an atypical meningioma WHO II° located in the left lateral ventricle. Three years after the tumor extirpation, the patient suffered from a hematoma in the fourth ventricle due to a recurrently haemorrhaged cavernoma. In 2008, a recurrence of the tumor in the left lateral ventricle was discovered. Additionally, another tumor located in the quadrigeminal lamina was detected. After surgical resection of the tumor in the left lateral ventricle, the pathological examination confirmed the diagnosis of a collision tumor consisting of components of a meningioma WHO II° and a cavernoma. Postoperatively, no adjuvant treatment was needed and no tumor recurrence is discovered up to the present. A possible explanation for the collision of those two different tumors may be migration of tumor cells mediated by the cerebrospinal fluid. After 5-years of follow-up, there is no sign of any tumor recurrence; therefore, surgical tumor removal without adjuvant therapy seems to be the treatment of choice.

  19. Les fluctuations supraconductrices dans le compose praseodyme-cerium-oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Renaud, Jacques

    Ce travail etudie les fluctuations supraconductrices dans le compose supraconducteur a haute temperature critique dope aux electrons Pr2-xCe xCuO4+delta. La technique utilisee pour sonder ces fluctuations est le transport electrique DC dans le plan ab. Il s'agit, a notre connaissance, de la premiere etude de ce type dans la classe generale des supraconducteurs a haute temperature critique dopes aux electrons et, plus particulierement, dans Pr2-xCe xCuO4+delta. De plus, l'etude est effectuee pour trois regimes de dopage, soit sous-dope x = 0.135, dopage optimal x = 0.15 et surdope x = 0.17. Les echantillons etudies sont des couches minces d'epaisseur plus grande que 100 nm crues par ablation laser. Les mesures electriques DC effectuees dans ce travail sont la resistance en reponse lineaire et les courbes IV en reponse non lineaire en fonction de la temperature. La mise en oeuvre experimentale de ces mesures a necessite une grande attention au filtrage et aux effets de chauffage a haut courant. Nous montrons que, sans cette attention, les donnees experimentales sont toujours erronees dans le regime pertinent pour nos echantillons. Les resultats pour le dopage optimal x = 0.15 sont expliques de facon tres convaincante dans le cadre de fluctuations purement 2D. D'abord, le regime des fluctuations gaussiennes est tres bien decrit par le modele d'Aslamazov-Larkin en deux dimensions. Ensuite, le regime de fluctuations critiques, se trouvant a plus basse temperature que le regime gaussien, est tres bien decrit par la physique 2D de Kosterlitz-Thouless. Dans cette analyse, les deux regimes ont des temperatures critiques coherentes entre elles, ce qui semble confirmer ce scenario 2D. Une analyse des donnees dans le cadre de fluctuations 3D est exploree mais donne des conclusions incoherentes. Les resultats pour les autres dopages sont qualitativement equivalents avec le dopage optimal et permettent donc une explication purement 2D. Par contre, contrairement au dopage optimal

  20. Collision Tumor Composed of Meningioma and Cavernoma

    PubMed Central

    Weigel, Jens; Neher, Markus; Schrey, Michael; Wünsch, Peter H.; Steiner, Hans-Herbert

    2017-01-01

    A true collision tumor is a rare entity composed of two histologically distinct neoplasms coinciding in the same organ. This paper reports a unique case of cerebral collision tumor consisting of two benign components. On the first hand, meningioma which is usually a benign lesion arising from the meningothelial cell in the arachnoidal membrane. On the other, cerebral cavernoma which is a well-circumscribed, benign vascular hamartoma within the brain. To our knowledge, there is no previously documented case of cerebral collision tumor consisting of two benign components. A 56-year-old Caucasian male suffered in 2002 from an atypical meningioma WHO II° located in the left lateral ventricle. Three years after the tumor extirpation, the patient suffered from a hematoma in the fourth ventricle due to a recurrently haemorrhaged cavernoma. In 2008, a recurrence of the tumor in the left lateral ventricle was discovered. Additionally, another tumor located in the quadrigeminal lamina was detected. After surgical resection of the tumor in the left lateral ventricle, the pathological examination confirmed the diagnosis of a collision tumor consisting of components of a meningioma WHO II° and a cavernoma. Postoperatively, no adjuvant treatment was needed and no tumor recurrence is discovered up to the present. A possible explanation for the collision of those two different tumors may be migration of tumor cells mediated by the cerebrospinal fluid. After 5-years of follow-up, there is no sign of any tumor recurrence; therefore, surgical tumor removal without adjuvant therapy seems to be the treatment of choice. PMID:28061500

  1. Joint Composable Object Model and LVC Methodology

    NASA Technical Reports Server (NTRS)

    Rheinsmith, Richard; Wallace, Jeffrey; Bizub, Warren; Ceranowicz, Andy; Cutts, Dannie; Powell, Edward T.; Gustavson, Paul; Lutz, Robert; McCloud, Terrell

    2010-01-01

    Within the Department of Defense, multiple architectures are created to serve and fulfill one or several specific service or mission related LVC training goals. Multiple Object Models exist across and within those architectures and it is there that those disparate object models are a major source of interoperability problems when developing and constructing the training scenarios. The two most commonly used architectures are; HLA and TENA, with DIS and CTIA following close behind in terms of the number of users. Although these multiple architectures can share and exchange data the underlying meta-models for runtime data exchange are quite different, requiring gateways/translators to bridge between the different object model representations; while the Department of Defense's use of gateways are generally effective in performing these functions, as the LVC environment increases so too does the cost and complexity of these gateways. Coupled with the wide range of different object models across the various user communities we increase the propensity for run time errors, increased programmer stop gap measures during coordinated exercises, or failure of the system as a whole due to unknown or unforeseen incompatibilities. The Joint Composable Object Model (JCOM) project was established under an M&S Steering Committee (MSSC)-sponsored effort with oversight and control placed under the Joint Forces Command J7 Advanced Concepts Program Directorate. The purpose of this paper is to address the initial and the current progress that has been made in the following areas; the Conceptual Model Development Format, the Common Object Model, the Architecture Neutral Data Exchange Model (ANDEM), and the association methodology to allow the re-use of multiple architecture object models and the development of the prototype persistent reusable library.

  2. Des ballons pour demain

    NASA Astrophysics Data System (ADS)

    Régipa, R.

    A partir d'une théorie sur la détermination des formes et des contraintes globales d'un ballon de révolution, ou s'en rapprochant, une nouvelle famille de ballons a été définie. Les ballons actuels, dits de ``forme naturelle'', sont calculés en général pour une tension circonférencielle nulle. Ainsi, pour une mission donnée, la tension longitudinale et la forme de l'enveloppe sont strictement imposées. Les ballons de la nouvelle génération sont globalement cylindriques et leurs pôles sont réunis par un câble axial, chargé de transmettre une partie des efforts depuis le crochet (pôle inférieur), directement au pôle supérieur. De plus, la zone latérale cylindrique est soumise à un faible champ de tensions circonférencielles. Ainsi, deux paramètres permettent de faire évoluer la distribution des tensions et la forme de l'enveloppe: - la tension du câble de liaison entre pôles (ou la longueur de ce câble) - la tension circonférencielle moyenne désirée (ou le rayon du ballon). On peut donc calculer et réaliser: - soit des ballons de forme adaptée, comme les ballons à fond plat pour le bon fonctionnement des montgolfières infrarouge (projet MIR); - soit des ballons optimisés pour une bonne répartition des contraintes et une meilleure utilisation des matériaux d'enveloppe, pour l'ensemble des programmes stratosphériques. Il s'ensuit une économie sensible des coûts de fabrication, une fiabilité accrue du fonctionnement de ces ballons et une rendement opérationnel bien supérieur, permettant entre autres, d'envisager des vols à très haute altitude en matériaux très légers.

  3. Report on the International Workshop on Progress towards Molecular Scale Electronics Held in University of Durham on 25-28 March 1990

    DTIC Science & Technology

    1990-03-28

    experimentally that the electrical signals are subject to modulation by the load resistance , the electrical characteristics of the supporting inert...Laboratoire des Materiaux Moleculaires, C.N.R.S. , 2 rue Henri-Dunant, 94320 Thiais, France Conjugated oligomers, such as thiophene derivatives, can be...and A. Skoulios Institute de Physique et Chimie des Materiaux de Strasbourg Groupe des Materiaux Organiques, I.C.S. Strasbourg, France R. D. Miller IBM

  4. Structural Effects in the Dielectric Constant Rare-Earth Oxides: Nd2O3

    DTIC Science & Technology

    2006-01-01

    ORGANIZATION REPORT NUMBER *Laboratoire d’Electrostatique at des Materiaux Dielectriques CNRS, BP 166 38042 Grenoble, Cedex, France...87117 and ,P. Gonon Laboratoire d’Electrostatique at des Materiaux Dielectriques, CNRS, BP 166, 38042 Grenoble, Cedex, France 1 also at...Laboratoire d’Electrostatique at des Materiaux Dielectriques, CNRS, BP 166, 38042 Grenoble, Cedex, France ABSTRACT Thin films of Nd2O3 have been

  5. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Fur products composed of pieces. 301.20... RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats and plates, are composed in whole or in substantial part...

  6. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Fur products composed of pieces. 301.20... RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats and plates, are composed in whole or in substantial part...

  7. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Fur products composed of pieces. 301.20... RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats and plates, are composed in whole or in substantial part...

  8. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Fur products composed of pieces. 301.20... RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats and plates, are composed in whole or in substantial part...

  9. 16 CFR 301.20 - Fur products composed of pieces.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Fur products composed of pieces. 301.20... RULES AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.20 Fur products composed of pieces. (a) Where fur products, or fur mats and plates, are composed in whole or in substantial part...

  10. Sequoias, Mavericks, Open Doors...Composing Joan Tower

    ERIC Educational Resources Information Center

    Allsup, Randall Everett

    2011-01-01

    This essay interview with Joan Tower is a meditation on the importance of composing, understood as a process larger than the making of new sound combinations or musical scores, suggesting that the compositional act is self-educative and self-forming. Tower's musical life, one of teaching and learning, one of composing and self-composing, is an…

  11. Maladie des vibrations

    PubMed Central

    Shen, Shixin (Cindy); House, Ronald A.

    2017-01-01

    Résumé Objectif Permettre aux médecins de famille de comprendre l’épidémiologie, la pathogenèse, les symptômes, le diagnostic et la prise en charge de la maladie des vibrations, une maladie professionnelle importante et courante au Canada. Sources d’information Une recherche a été effectuée sur MEDLINE afin de relever les recherches et comptes rendus portant sur la maladie des vibrations. Une recherche a été effectuée sur Google dans le but d’obtenir la littérature grise qui convient au contexte canadien. D’autres références ont été tirées des articles relevés. Message principal La maladie des vibrations est une maladie professionnelle répandue touchant les travailleurs de diverses industries qui utilisent des outils vibrants. La maladie est cependant sous-diagnostiquée au Canada. Elle compte 3 éléments : vasculaire, sous la forme d’un phénomène de Raynaud secondaire; neurosensoriel; et musculosquelettique. Aux stades les plus avancés, la maladie des vibrations entraîne une invalidité importante et une piètre qualité de vie. Son diagnostic exige une anamnèse minutieuse, en particulier des antécédents professionnels, un examen physique, des analyses de laboratoire afin d’éliminer les autres diagnostics, et la recommandation en médecine du travail aux fins d’investigations plus poussées. La prise en charge consiste à réduire l’exposition aux vibrations, éviter les températures froides, abandonner le tabac et administrer des médicaments. Conclusion Pour assurer un diagnostic rapide de la maladie des vibrations et améliorer le pronostic et la qualité de vie, les médecins de famille devraient connaître cette maladie professionnelle courante, et pouvoir obtenir les détails pertinents durant l’anamnèse, recommander les patients aux cliniques de médecine du travail et débuter les demandes d’indemnisation de manière appropriée. PMID:28292812

  12. Mesures experimentales de l'impact des revetements hydrophobeset superhydrophobes sur la trainee et la portance d'un profil aerodynamique propre et glace

    NASA Astrophysics Data System (ADS)

    Villeneuve, Eric

    Ce projet, realise a la demande du Laboratoire International des Materiaux Antigivre, a pour but de mesurer et definir experimentalement l'impact de revetements hydrophobes sur les coefficients de trainee et de portance d'un profil NACA 0012. Pour ce faire, la balance aerodynamique du LIMA devait tout d'abord etre amelioree afin d'offrir une sensibilite suffisante pour realiser le projet. Plusieurs ameliorations ont ete faites, comme le changement des cellules de charge, la diminution du nombre de cellules de charge, le changement du cadre de la balance, etc. Une fois ces ameliorations terminees, la reproductibilite, l'exactitude et la sensibilite ont ete valides afin de s'assurer de la fiabilite des resultats offerts par la balance. Pour les angles d'attaque etudies avec les revetements, soient -6° et 0°, la balance a une reproductibilite de +/-2,06% a 360 000 de nombre de Reynolds. Pour valider la sensibilite, des essais a -6° et 0° d'angle d'attaque et des nombres de Reynolds de 360 000 et 500 000 ont ete faits avec des papiers sables. Les resultats de ces essais ont permis de, tracer des courbes de tendances du coefficient de trainee du NACA 0012 en fonction de la rugosite de surface et d'etablir la valeur de la sensibilite de la balance a +/-8 mu m. Cinq revetements populaires ont ete choisis pour l'experimentation, soient le Wearlon, le Staclean, le Hirec, le Phasebreak ainsi que le Nusil. Les revetements sont soumis aux memes conditions experimentales que les papiers sables, et une rugosite equivalente est trouvee par extrapolation des resultats. Cependant, les rugosites equivalentes de surfaces different entre -6° et 0°. Les essais avec le Staclean et le Hirec donnent des coefficients de trainee equivalent a ceux avec l'aluminium, alors que le Wearlon, le Nusil et le Phasebreak donnent une augmentation du coefficient de trainee de 13%, 17% et 25% respectivement par rapport a l'aluminium. Pour les coefficients de portance, la balance ne detecte pas l

  13. Des Vents et des Jets Astrophysiques

    NASA Astrophysics Data System (ADS)

    Sauty, C.

    well expected result from the theory. Although, collimation may be conical, paraboloidal or cylindrical (Part 4), cylindrical collimation is the more likely to occur. The shape of outflows may then be used as a tool to predict physical conditions on the flows or on their source. L'éjection continue de plasma autour d'objets massifs est un phénomène largement répandu en astrophysique, que ce soit sous la forme du vent solaire, de vents stellaires, de jets d'étoiles en formation, de jets stellaires autour d'objets compacts ou de jets extra-galactiques. Cette zoologie diversifiée fait pourtant l'objet d'un commun effort de modélisation. Le but de cette revue est d'abord de présenter qualitativement le développement, depuis leur origine, des diverses théories de vents (Partie 1) et l'inter disciplinarité dans ce domaine. Il s'agit d'une énumération, plus ou moins exhaustive, des idées proposées pour expliquer l'accélération et la morphologie des vents et des jets, accompagnée d'une présentation sommaire des aspects observationnels. Cette partie s'abstient de tout aspect faisant appel au formalisme mathématique. Ces écoulements peuvent être décrits, au moins partiellement, en résolvant les équations magnétohydrodynamiques, axisymétriques et stationnaires. Ce formalisme, à la base de la plupart des théories, est exposé dans la Partie 2. Il permet d'introduire quantitativement les intégrales premières qu'un tel système possède. Ces dernières sont amenées à jouer un rôle important dans la compréhension des phénomènes d'accélération ou de collimation, en particulier le taux de perte de masse, le taux de perte de moment angulaire ou l'énergie du rotateur magnétique. La difficulté de modélisation réside dans l'existence de points critiques, propres aux équations non linéaires, qu'il faut franchir. La nature physique et la localisation de ces points critiques fait l'objet d'un débat important car ils sont la clef de voute de la r

  14. Etude des phenomenes dynamiques ultrarapides et des caracteristiques impulsionnelles d'emission terahertz du supraconducteur YBCO

    NASA Astrophysics Data System (ADS)

    Savard, Stephane

    Les premieres etudes d'antennes a base de supraconducteurs a haute temperature critique emettant une impulsion electromagnetique dont le contenu en frequence se situe dans le domaine terahertz remontent a 1996. Une antenne supraconductrice est formee d'un micro-pont d'une couche mince supraconductrice sur lequel un courant continu est applique. Un faisceau laser dans le visible est focalise sur le micro-pont et place le supraconducteur dans un etat hors-equilibre ou des paires sont brisees. Grace a la relaxation des quasiparticules en surplus et eventuellement de la reformation des paires supraconductrices, nous pouvons etudier la nature de la supraconductivite. L'analyse de la cinetique temporelle du champ electromagnetique emis par une telle antenne terahertz supraconductrice s'est averee utile pour decrire qualitativement les caracteristiques de celle-ci en fonction des parametres d'operation tels que le courant applique, la temperature et la puissance d'excitation. La comprehension de l'etat hors-equilibre est la cle pour comprendre le fonctionnement des antennes terahertz supraconductrices a haute temperature critique. Dans le but de comprendre ultimement cet etat hors-equilibre, nous avions besoin d'une methode et d'un modele pour extraire de facon plus systematique les proprietes intrinseques du materiau qui compose l'antenne terahertz a partir des caracteristiques d'emission de celle-ci. Nous avons developpe une procedure pour calibrer le spectrometre dans le domaine temporel en utilisant des antennes terahertz de GaAs bombarde aux protons H+ comme emetteur et detecteur. Une fois le montage calibre, nous y avons insere une antenne emettrice dipolaire de YBa 2Cu3O7-delta . Un modele avec des fonctions exponentielles de montee et de descente du signal est utilise pour lisser le spectre du champ electromagnetique de l'antenne de YBa 2Cu3O7-delta, ce qui nous permet d'extraire les proprietes intrinseques de ce dernier. Pour confirmer la validite du modele

  15. Syllabus for a Women Studies Course on Women Composers.

    ERIC Educational Resources Information Center

    Hayes, Deborah

    An upper division college-level course dealing with women composers for both music majors and nonmusic majors is outlined. The course provides an historical and analytical survey of western music through works composed by women, with emphasis on the 19th and 20th centuries. Students listen to music, participate in class discussions, and listen to…

  16. A Taxonomy for Composing Effective Naval Teams. Final Report.

    ERIC Educational Resources Information Center

    Driskell, James E.; And Others

    Since teams perform a majority of mission-critical Navy tasks, a significant applied research problem is how to compose maximally effective task teams. Two problems have traditionally hindered the attainment of this goal: how to compose teams on bases other than ability or technical skill and how to classify team tasks, so that predictions can be…

  17. Grammar for College Writing: A Sentence-Composing Approach

    ERIC Educational Resources Information Center

    Killgallon, Don; Killgallon, Jenny

    2010-01-01

    Across America, in thousands of classrooms, from elementary school to high school, the time-tested sentence-composing approach has given students tools to become better writers. Now the authors present a much anticipated sentence-composing grammar worktext for college writing. This book presents a new and easier way to understand grammar: (1) Noun…

  18. Collaborative Composing in High School String Chamber Music Ensembles

    ERIC Educational Resources Information Center

    Hopkins, Michael T.

    2015-01-01

    The purpose of this study was to examine collaborative composing in high school string chamber music ensembles. Research questions included the following: (a) How do high school string instrumentalists in chamber music ensembles use verbal and musical forms of communication to collaboratively compose a piece of music? (b) How do selected variables…

  19. How Composers Approach Teaching Composition: Strategies for Music Teachers

    ERIC Educational Resources Information Center

    Randles, Clint; Sullivan, Mark

    2013-01-01

    Composition pedagogy is explored from the perspective of a composer and a music teacher educator in this article. The primary goal is to help practicing music teachers develop strategies that will encourage students to create original music. The authors provide reflection about the process of helping students compose on the basis of personal…

  20. Composing in Public: The Ambient Audiences of a Writing Lab

    ERIC Educational Resources Information Center

    Hall, Matthew

    2015-01-01

    Although scholars have investigated the ways youths individually enact composing practices and the impact of audience on these practices, this study examines the impact of an audience physically present while composing in a shared, public space--an ambient audience. Blurring the line between traditional notions of audience and collaborator through…

  1. The Links between Handwriting and Composing for Y6 Children

    ERIC Educational Resources Information Center

    Medwell, Jane; Strand, Steve; Wray, David

    2009-01-01

    Although handwriting is often considered a matter of presentation, a substantial body of international research suggests that the role of handwriting in children's composing has been neglected. Automaticity in handwriting is now seen as of key importance in composing but this proposition is relatively untested in the UK and the assumption has been…

  2. The composing process of technical writers: A preliminary study

    NASA Technical Reports Server (NTRS)

    Mair, D.; Roundy, N.

    1981-01-01

    The assumption that technical writers compose as do other writers is tested. The literature on the composing process, not limited to the pure or applied sciences, was reviewed, yielding three areas of general agreement. The composing process (1) consists of several stages, (2) is reflexive, and (3) may be mastered by means of strategies. Data on the ways technical writers compose were collected, and findings were related to the three areas of agreement. Questionnaires and interviews surveying 70 writers were used. The disciplines represented by these writers included civil, chemical, agricultural, geological, mechanical, electrical, and petroleum engineering, chemistry, hydrology, geology, and biology. Those providing consulting services, or performing research. No technical editors or professional writers were surveyed, only technicians, engineers, and researchers whose jobs involved composing reports. Three pedagogical implications are included.

  3. Injectabilite des coulis de ciment dans des milieux fissures

    NASA Astrophysics Data System (ADS)

    Mnif, Thameur

    Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

  4. Stroke, music, and creative output: Alfred Schnittke and other composers.

    PubMed

    Zagvazdin, Yuri

    2015-01-01

    Alfred Schnittke (1934-1998), a celebrated Russian composer of the twentieth century, suffered from several strokes which affected his left cerebral hemisphere. The disease, however, did not diminish his musical talent. Moreover, he stated that his illness in a way facilitated his work. The composer showed amazingly high productivity after his first and second injuries of the central nervous system. The main topic of this chapter is the effect of strokes on Schnittke's output, creativity, and style of music. A brief biography of the composer with the chronology of his brain hemorrhages is included. In addition, the influence of cerebrovascular lesions on creative potential of other prominent composers such as Benjamin Britten, Jean Langlais, Vissarion Shebalin, Igor Stravinsky, and Ira Randall Thompson is discussed.

  5. Grundlagen des Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Mayer, Jörg; Blum, Janaki; Wintermantel, Erich

    Die Organtransplantation stellt eine verbreitete Therapie dar, um bei krankheitsoder unfallbedingter Schädigung eines Organs die Gesamtheit seiner Funktionen wieder herzustellen, indem es durch ein Spenderorgan ersetzt wird. Organtransplantationen werden für die Leber, die Niere, die Lunge, das Herz oder bei schweren grossflächigen Verbrennungen der Haut vorgenommen. Der grosse apparative, personelle und logistische Aufwand und die Risiken der Transplantationschirurgie (Abstossungsreaktionen) sowie die mangelnde Verfügbarkeit von immunologisch kompatiblen Spenderorganen führen jedoch dazu, dass der Bedarf an Organtransplantaten nur zu einem sehr geringen Teil gedeckt werden kann. Sind Spenderorgane nicht verfügbar, können in einzelnen Fällen lebenswichtige Teilfunktionen, wie beispielsweise die Filtrationsfunktion der Niere durch die Blutreinigung mittels Dialyse ersetzt oder, bei mangelnder Funktion der Bauchspeicheldrüse (Diabetes), durch die Verabreichung von Insulin ein normaler Zustand des Gesamtorganismus auch über Jahre hinweg erhalten werden. Bei der notwendigen lebenslangen Anwendung apparativer oder medikamentöser Therapie können für den Patienten jedoch häufig schwerwiegende, möglicherweise lebensverkürzende Nebenwirkungen entstehen. Daher werden in der Forschung Alternativen gesucht, um die Funktionen des ausgefallenen Organs durch die Implantation von Zellen oder in vitro gezüchteten Geweben möglichst umfassend wieder herzustellen. Dies erfordert biologisch aktive Implantate, welche die für den Stoffwechsel des Organs wichtigen Zellen enthalten und einen organtypischen Stoffwechsel entfalten.

  6. Transparent Glass Ceramics Doped by Chromium(III) and Chromium(III) and Neodymium(III) as New Materials for Lasers and Luminescent Solar Concentrators.

    DTIC Science & Technology

    1987-04-30

    Laboratoire de Physico-Chimie des Materiaux Luminescents Universite Claude Bernard Lyon-Unite associee au CNRS 69622 - Villeurbanne, France Anne-Marie...Bouderbala, Georges Boulon Laboratoire de Physico-Chemie des Materiaux Luminescents Universite Claude Bernard Lyon - Unite associee au CNRS 69622

  7. Reticulation des fibres lignocellulosiques

    NASA Astrophysics Data System (ADS)

    Landrevy, Christel

    Pour faire face à la crise économique la conception de papier à valeur ajoutée est développée par les industries papetières. Le but de se projet est l'amélioration des techniques actuelles de réticulation des fibres lignocellulosiques de la pâte à papier visant à produire un papier plus résistant. En effet, lors des réactions de réticulation traditionnelles, de nombreuses liaisons intra-fibres se forment ce qui affecte négativement l'amélioration anticipée des propriétés physiques du papier ou du matériau produit. Pour éviter la formation de ces liaisons intra-fibres, un greffage sur les fibres de groupements ne pouvant pas réagir entre eux est nécessaire. La réticulation des fibres par une réaction de « click chemistry » appelée cycloaddition de Huisgen entre un azide et un alcyne vrai, catalysée par du cuivre (CuAAC) a été l'une des solutions trouvée pour remédier à ce problème. De plus, une adaptation de cette réaction en milieux aqueux pourrait favoriser son utilisation en milieu industriel. L'étude que nous désirons entreprendre lors de ce projet vise à optimiser la réaction de CuAAC et les réactions intermédiaires (propargylation, tosylation et azidation) sur la pâte kraft, en milieu aqueux. Pour cela, les réactions ont été adaptées en milieu aqueux sur la cellulose microcristalline afin de vérifier sa faisabilité, puis transférée à la pâte kraft et l'influence de différents paramètres comme le temps de réaction ou la quantité de réactifs utilisée a été étudiée. Dans un second temps, une étude des différentes propriétés conférées au papier par les réactions a été réalisée à partir d'une série de tests papetiers optiques et physiques. Mots Clés Click chemistry, Huisgen, CuAAC, propargylation, tosylation, azidation, cellulose, pâte kraft, milieu aqueux, papier.

  8. La diffraction des neutrons et des rayons X pour l'étude structurale des liquides et des verres

    NASA Astrophysics Data System (ADS)

    Fischer, H. E.; Salmon, P. S.; Barnes, A. C.

    2003-02-01

    La compréhension de mainte propriété physique d'un verre ou d'un liquide nécessite la connaissance des facteurs de structure partiels (PSFs) qui décrivent chacun la distribution d'une espèce atomique autour d'une autre. La technique de diffraction des neutrons avec substitution isotopique (NDIS) [1,2,3], ayant bien réussi a déterminer les PSFs de certains composés [4,5], est pourtant restreinte aux isotopes présentant un contraste suffisant en longueur de diffusion. D'un autre cote, la technique de diffusion anomale des rayons X (AXS ou AXD) [6] permet de faire varier la longueur de diffusion d'une espèce atomique pourvu que son énergie d'absorption soit à la fois accessible et suffisamment élevée pour donner un assez grand transfert du moment. La combinaison des techniques de diffraction des neutrons (avec ou sans substitution isotopique) et de diffraction des rayons X (avec ou sans diffusion anomale) peut donc permettre d'obtenir un meilleur contraste en longueurs de diffusion pour un système donné, mais exige une analyse de données plus soignée pour pouvoir bien tenir compte des erreurs systématiques qui sont différentes pour les 2 techniques [7]. Pour les atomes ayant des distributions électroniques quasi-sphériques, e.g. dans le cas d'un alliage liquide, la combinaison des techniques de NDIS et de diffraction des rayons X s'est déjà montrée très avantageuse pour la détermination des PSFs [8,9]. Dans le cas des verres ayant d'importantes liaisons covalentes, l'effective combinaison des 2 techniques peut être moins directe mais facilitée lorsqu'il s'agit des atomes de grand Z [10,11]. Nous présentons ici un sommaire du méthode et quelques exemples des résultats.

  9. Composed planar Hall effect sensors with dual-mode operation

    NASA Astrophysics Data System (ADS)

    Mor, Vladislav; Roy, Debangsu; Schultz, Moty; Klein, Lior

    2016-02-01

    We present a composed planar Hall effect sensor with two modes of operation: (a) an ON mode where the composed sensor responds to magnetic field excitations similarly to the response of a regular planar Hall effect sensor, and (b) an OFF mode where the response is negligible. The composed planar Hall effect sensor switches from the OFF mode to the ON mode when it is exposed to a magnetic field which exceeds a certain threshold determined by the sensor design. The features of this sensor make it useful as a switch triggered by magnetic field and as a sensing device with memory, as its mode of operation indicates exposure to a magnetic field larger than a certain threshold without the need to be activated during the exposure itself.

  10. Layout modification for library cell Alt-PSM composability

    NASA Astrophysics Data System (ADS)

    Cao, Ke; Hu, Jiang; Cheng, Mosong

    2004-05-01

    In sub-wavelength lithography, light field Alt-PSM (Alternating Phase Shifting Mask) is an essential technology for poly layer printability. In a standard cell based design, the problem of obtaining Alt-PSM compliance for an individual cell layout has been solved well [3]. However, placing Alt-PSM compliant cells together can not guarantee Alt-PSM compliance of the entire chip/block layout due to phase interactions among adjacent cells. A simple solution to this Alt-PSM composability problem is to wrap blank area around each cell, which is very inefficient on chip area usage. In this paper, we formulate the composability problem as a graph model and propose a polynomial time optimal algorithm to achieve Alt-PSM composability with the least impact on cell layout.

  11. Missile Aerodynamics (Aerodynamique des Missiles)

    DTIC Science & Technology

    1998-11-01

    guerre froide la production des missiles a baisse’, avec pour consequence une diminution des budgets de d6veloppement. Les nouveaux types de conflits ...Roma) Directeur - Gestion de l’information LUXEMBOURG (Recherche et developpement) - DRDGI 3 Voir Belgique Ministbre de la Difense nationale NORVEGE

  12. "Convince Me!" Valuing Multimodal Literacies and Composing Public Service Announcements

    ERIC Educational Resources Information Center

    Selfe, Richard J.; Selfe, Cynthia L.

    2008-01-01

    For some teachers, the increasing attention to digital and multimodal composing in English and Language Arts classrooms has brought into sharp relief the profession's investment in print as the primary means of expression. Although new forms of communication that combine words, still and moving images, and animation have begun to dominate digital…

  13. "Composing Visual History: Using Powerpoint Slideshows to Explore Historical Narrative"

    ERIC Educational Resources Information Center

    Fehn, Bruce

    2007-01-01

    This article explores PowerPoint slideshow's capacities for introducing history teachers and students to the pictorial and digital turns for representing and narrating the past. Based upon this research, the author argues that image-dominated PowerPoint slideshow provides teachers and students with a unique and powerful tool for composing and…

  14. Beyond the Enthymeme: Sorites, Critical Thinking, and the Composing Process.

    ERIC Educational Resources Information Center

    Hill, Carolyn

    A teacher presents a writing exercise designed to facilitate audience-directed, critical thinking during the process of composing, that starts students thinking in terms of sorites and enthymemes. Students first read a CIA manual, "Psychological Operations in Guerrilla Warfare," that instructs the Contra guerrillas in illegal acts and…

  15. Composing Cinquain Poems with Basic Parts of Speech.

    ERIC Educational Resources Information Center

    Gardner, Traci

    The writing program described in this lesson plan guides students in grades 3 through 8 in composing cinquain poems, a five-line form that uses the syllable count of two-four-six-eight-two. During the two 50-minute lessons, students will: describe the basic conventions of cinquain; interpret examples of cinquain; characterize the relationship…

  16. Composing the Career Portfolio and the Classed Subject

    ERIC Educational Resources Information Center

    Collin, Ross

    2012-01-01

    In this article, I consider how subjectivities are composed and assessed within the boundaries of a career-focused portfolio program. First, by examining how portfolio composition is taught in senior English courses, I identify the qualities of the subject position students are called to occupy. Next, I present discourse analyses of portfolio…

  17. Preparing Performers and Composers for Effective Educational Work with Children

    ERIC Educational Resources Information Center

    Myers, David E.

    2005-01-01

    Music education programs stand to gain important benefits from the collaborative work of performing musicians with specialist music teachers and classroom teachers. To be effective, performers and composers must have their knowledge and skills for education cultivated within the context of their essential identities as musicians. Given…

  18. When Did Classic Composers Make Their Best Work?

    ERIC Educational Resources Information Center

    Franses, Philip Hans

    2016-01-01

    This Research Note shows that classic composers created their best works when they were at a similar age when creators in other domains did their best work, namely when they were at an age that represented around 60% of their life span. This finding is very similar to earlier results for painters and authors.

  19. Composing Songs for Teaching Science to College Students

    ERIC Educational Resources Information Center

    Yee Pinn Tsin, Isabel

    2015-01-01

    Recent studies have shown that songs may enhance learning as they function as mnemonic devices to increase memorability. In this research, songs based on the more difficult subtopics in Chemistry were composed, encompassing many formulas, equations and facts to be remembered. This technique of song composition can be used in any subject, any point…

  20. Teaching Effective Communication Skills with ACE: Analyzing, Composing, & Evaluating

    ERIC Educational Resources Information Center

    Snyder, Lisa Gueldenzoph; Shwom, Barbara

    2011-01-01

    Most business communication classes teach students to use a writing process to compose effective documents. Students practice the process by applying it to various types of writing with various purposes-reports, presentations, bad news letters, persuasive memos, etc. However, unless students practice that process in other contexts outside of the…

  1. Etude des proprietes electroniques des etats fondamentaux aux facteurs de remplissage entiers dans la bicouche de graphene

    NASA Astrophysics Data System (ADS)

    Lemonde, Marc-Antoine

    Dans ce document, on etudie les proprietes electroniques d'un systeme compose de deux couches de graphene separees par un dielectrique en presence d'un fort champ magnetique perpendiculaire. L'epaisseur du dielectrique est choisie de facon a pouvoir negliger le transfert de charges par effet tunnel. Ce type de systeme est etudie par quelques groupes de recherche dans le principal but de predire et comprendre la formation de condensat de Bose-Einstein d'excitons dont les composants sont des fermions relativistes sans masse [1] [2] [3]. Nous nous interessons a l'effet de l'interaction electron-electron sur les etats fondamentaux de ce systeme et 'a leurs excitations collectives a facteur de remplissage entier. Plus precisement, nous etudions les diagrammes de phase de cette bicouche de graphene sans terme tunnel dans le niveau de Landau n = 0 pour les facteurs de remplissage nu = 1 et nu = 2 dans la limite ou la temperature tend vers zero. Lors de cette etude, nous appuyons les predictions faites par Allan H. MacDonald et Yogesh N. Joglekar a propos de la formation d'un condensat de Bose-Einstein d'excitons pour differentes zones des diagrammes de phase. Nous etudions aussi la relation de dispersion des excitations collectives soutenues par les etats fondamentaux et leur effet sur le systeme. Finalement, nous nous interessons a la conductivite du systeme. Nous demontrons alors les regles de selection pour l'absorption inter-niveaux de Landaux et nous etudions l'effet des modes collectifs sur l'absorption .intrarniveau de Landau, Ce dernier phenomene ressort directement de la forme particuliere du reseau atomique du graphene et nous proposons dans ce document une toute premiere etude de ce concept. Mots-cles : graphene, gaz d'electrons bidimensionnel, effets Hall quantiques, proprietes electroniques, modes collectifs

  2. Composing Texts, Composing Lives.

    ERIC Educational Resources Information Center

    Perl, Sondra

    1994-01-01

    Using composition, reader response, critical, and feminist theories, a teacher demonstrates how adult students respond critically to literary texts and how teachers must critically analyze the texts of their teaching practice. Both students and teachers can use writing to bring their experiences to interpretation. (SK)

  3. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  4. The rainbow effect on composing chaotic algorithmic music

    NASA Astrophysics Data System (ADS)

    Sotiropoulos, Vaggelis D.

    The effect of rainbow color sequence on composing chaotic algorithmic music is examined. The mathematical range of the chaotic algorithm is mapped onto musical notes whose sequence follows the sequence of the seven main rainbow colors and their in-between five auxiliary colors. Each musical note is identified with the frequency of a color by a frequency shift. As a result, for a single rainbow, the scale of the chaotic music comprises an ascending chromatic F major scale without the thirteenth note, followed by its corresponding descending chromatic scale, for a total of twenty four notes. For aesthetic purposes, a note can be placed in any octave at the composer's will. The effect of a double rainbow on composing chaotic music is also studied. It is known from nature that the outer bow has its color sequence reversed. Thus, in this case, the double rainbow musical scale comprises forty eight notes on a repeated reversed full chromatic F major scale without the thirteenth note in the ascent or the first note in the descent, resembling in shape the letter w. Colorless regions in the rainbow or dark (Alexander's bands) regions in a supernumerary rainbow are included in the musical range as rests. With the musical scale based on the described rainbow mapping, chaotic music is composed from an algorithm defined by a semi-elliptical first order iterative map. The minor axis of the ellipse is defined by the range of the mathematical pitch from 0 to 1 while the semi-major axis by that of the succeeding pitch from 0 to r/2; r is a free parameter that varies from 1 to 2 to be chosen by the composer. The lower limiting value of the free parameter r corresponds to a circle of radius 1/2 yielding steady state music whereas all the other values of r correspond to ellipses. Chaotic compositions result from r values between 1.95 and 2, the latter value yielding full chaos from an ellipse with its major axis double its minor axis. Fixed notes are obtained for all r's, i.e., notes

  5. Modeling and Composing Scenario-Based Requirements with Aspects

    NASA Technical Reports Server (NTRS)

    Araujo, Joao; Whittle, Jon; Ki, Dae-Kyoo

    2004-01-01

    There has been significant recent interest, within the Aspect-Oriented Software Development (AOSD) community, in representing crosscutting concerns at various stages of the software lifecycle. However, most of these efforts have concentrated on the design and implementation phases. We focus in this paper on representing aspects during use case modeling. In particular, we focus on scenario-based requirements and show how to compose aspectual and non-aspectual scenarios so that they can be simulated as a whole. Non-aspectual scenarios are modeled as UML sequence diagram. Aspectual scenarios are modeled as Interaction Pattern Specifications (IPS). In order to simulate them, the scenarios are transformed into a set of executable state machines using an existing state machine synthesis algorithm. Previous work composed aspectual and non-aspectual scenarios at the sequence diagram level. In this paper, the composition is done at the state machine level.

  6. A Design for Composing and Extending Vehicle Models

    NASA Technical Reports Server (NTRS)

    Madden, Michael M.; Neuhaus, Jason R.

    2003-01-01

    The Systems Development Branch (SDB) at NASA Langley Research Center (LaRC) creates simulation software products for research. Each product consists of an aircraft model with experiment extensions. SDB treats its aircraft models as reusable components, upon which experiments can be built. SDB has evolved aircraft model design with the following goals: 1. Avoid polluting the aircraft model with experiment code. 2. Discourage the copy and tailor method of reuse. The current evolution of that architecture accomplishes these goals by reducing experiment creation to extend and compose. The architecture mechanizes the operational concerns of the model's subsystems and encapsulates them in an interface inherited by all subsystems. Generic operational code exercises the subsystems through the shared interface. An experiment is thus defined by the collection of subsystems that it creates ("compose"). Teams can modify the aircraft subsystems for the experiment using inheritance and polymorphism to create variants ("extend").

  7. 1. General view, outbuildings. The seed house composed of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view, outbuildings. The seed house composed of the greenhouse, a storeroom (shed), a classroom (over a former ice pit), and a kitchen (over a cellar)-stands on the right. The barn roof is visible at center and the gift shop (former stable) stands on the left (Note the carved stone posts framing the gateway). - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  8. PLZT block data composers operated in differential phase mode

    NASA Technical Reports Server (NTRS)

    Drake, M. D.; Klingler, D. E.

    1973-01-01

    The use of a PLTZ block data composer as a matrix type phase modulator to record and process digital data by the differential phase mode in a holographic recording/processing system was investigated. The system has readout contrast ratios of between 10 and 15 to 1. The differential phase mode has the advantage that strain bias is not required and thickness and strain variations in the PLZT are cancelled out.

  9. Towards a Dynamic DES model

    NASA Astrophysics Data System (ADS)

    Subbareddy, Pramod; Candler, Graham

    2009-11-01

    Hybrid RANS/LES methods are being increasingly used for turbulent flow simulations in complex geometries. Spalart's detached eddy simulation (DES) model is one of the more popular ones. We are interested in examining the behavior of the Spalart-Allmaras (S-A) Detached Eddy Simulation (DES) model in its ``LES mode.'' The role of the near-wall functions present in the equations is analyzed and an explicit analogy between the S-A and a one-equation LES model based on the sub-grid kinetic energy is presented. A dynamic version of the S-A DES model is proposed based on this connection. Validation studies and results from DES and LES applications will be presented and the effect of the proposed modification will be discussed.

  10. Etude theorique et experimentale de la correlation entre la resistance aux chocs thermiques et aux chocs mecaniques des materiaux refractaires utilises dans les fours de traitement de l'aluminium

    NASA Astrophysics Data System (ADS)

    Sebbani, Mohamed Jamal Eddine

    2001-07-01

    This work is a theoretical and experimental study of the correlation between the resistance to thermal shock and mechanical shock of refractory materials. The study of thermal shock showed that the Bahr and Hasselman approaches are alike and that they can be combined into a single, more general approach. This generalisation allowed the division of the theoretical models into two groups: the Hasselman model and the Harmuth model. However, neither of these approaches can predict the behaviour of all refractory materials submitted to thermal shock. Therefore, the generalisation of the Hasselman approach is more appropriate for more dense materials while the Hartmuth approach is more appropriate for less dense materials. The influence of porosity on the energy of rupture helped to explain the behaviour of the less dense material. The absence of generalisation in this case allows those parameters that could be correlated with thermal shock resistance to be dependent on the type of refractory. The study of mechanical shock provided a better understanding of this mechanism. The work performed showed, theoretically and experimentally, that the resistance of the refractory materials could be correlated with the parameter s20 Egwof n-22 . This new parameter helped to explain the statistical correlation between the resistance to mechanical impact and the soxRst parameter established in earlier work. The sintering influence, which makes the refractories more resistant to this type of demand, notably by reducing the "n" coefficient, was shown. This part of the study allowed the establishment of equivalence between thermal fatigue and fatigue by mechanical impact. An evaluation of the correlation between the two mechanisms demonstrated, theoretically and experimentally, that the mechanical and thermal demands could only be exceptionally correlated. In the case of thermal shock, which are imposed deformation demands, it is the shorter cracks which are the most dangerous. However, in the case of mechanical shock, which is constraint imposed, it is the longer cracks that are the most harmful. (Abstract shortened by UMI.)

  11. The Utilization of Advanced Composites in Military Aircraft Held in San Diego, California on 7-11 October 1991 (L’Emploi des Materiaux Composites de Pointe pour les Avions Militaires)

    DTIC Science & Technology

    1992-04-01

    I .. -m e,. Preface At its 73rd meeting in dhe fall of 199 1, the Structures and Materials Panel held a Workshuop toaddress compression loading...of compression failure wee key issues in the development of compressi’in test methods. In the area of fluid effects, a lack of a comprehensimve data...identifying key issues related to compression loading and fluid eecsin composite materials. Pre’face Lors de sa 73eme reunion. au printemp% 1991. Ic Panel

  12. "Bonjour History": Materials and Ideas for Teaching Louisiana's Cajun History = "Bonjour l'Histoire": Quelques Idees, Deux ou Trois Activites, et Plusieurs Materiaux pour l'Enseignement de l'Histoire des Cadiens en Louisiane.

    ERIC Educational Resources Information Center

    Mounier, Brenda

    The goals of this teacher's guidebook and videotape are designed to incorporate Acadian (Cajun) history into the 4th grade social studies curriculum and the 4th and 5th grade Louisiana 30-minute daily French programs and French immersion programs. Another goal is to create an awareness, appreciation, and understanding of Acadian history in…

  13. Photonic quantum well composed of photonic crystal and quasicrystal

    NASA Astrophysics Data System (ADS)

    Xu, Shaohui; Zhu, Yiping; Wang, Lianwei; Yang, Pingxiong; Chu, Paul K.

    2014-02-01

    A photonic quantum well structure composed of photonic crystal and Fibonacci quasicrystal is investigated by analyzing the transmission spectra and electric field distributions. The defect band in the photonic well can form confined quantized photonic states that can change in the band-gap of the photonic barriers by varying the thickness ratio of the two stacking layers. The number of confined states can be tuned by adjusting the period of the photonic well. The photons traverse the photonic quantum well by resonance tunneling and the coupling effect leads to the high transmission intensity of the confined photonic states.

  14. System Composer: Technology for rapid system integration and remote collaboration

    SciTech Connect

    Davies, B.R.; Palmquist, R.D.

    1996-03-01

    Sandia National Laboratories has developed an approach to the design, evaluation, deployment and operation of intelligent systems which is called System Composer. This toolkit provides an infrastructure and architecture for robot and automation system users to readily integrate system components and share mechatronic, sensor, and information resources over networks. The technology described in this paper provides a framework for real-time collaboration between researchers, manufacturing entities, design entities, and others without regard to relative location. An overview of the toolkit including its elements and architecture is provided along with examples of its use.

  15. The clinician's guide to composing effective business plans.

    PubMed

    Ettinger, Alan B; Blondell, Catherine

    2011-01-01

    In today's challenging healthcare environment, clinicians need to understand the fundamentals of financial analysis, which are the underpinnings of their clinical programs, especially when seeking administrative support for new initiatives. The business plan for new clinical program initiatives is composed of diverse elements such as the mission statement, market and competitive analyses, operations plan, and financial analysis. Armed with a basic knowledge of financial analysis of clinical programs, as well as forward-looking analysis of an initiative's added value, the healthcare provider can work much more effectively with administration in developing or creating new healthcare program initiatives.

  16. Efficient Non-interactive Universally Composable String-Commitment Schemes

    NASA Astrophysics Data System (ADS)

    Nishimaki, Ryo; Fujisaki, Eiichiro; Tanaka, Keisuke

    The universal composability (UC) for commitment is a very strong security notion. It guarantees that commitment schemes remain secure even if they are composed with arbitrary protocols and polynomially many copies of the schemes are run concurrently. Several UC commitment schemes in the common reference string (CRS) model have been proposed, but, they are either interactive commitment or bit-commitment (not string-commitment) schemes. We propose new non-interactive string-commitment schemes that achieve UC security in the CRS model assuming the difficulty of the decisional Diffie-Hellman problem or the decisional composite residuosity problem, but our schemes are not reusable. The main building blocks of our constructions are all-but-one trapdoor functions (ABO-TDFs) introduced by Peikert and Waters in STOC 2008 to construct secure public-key encryption schemes. Our main idea is to use the homomorphic properties of the function indices of the all-but-one trapdoor functions and to extend the functions to probabilistic ones by using re-randomization of ciphertexts. This is a new application of ABO-TDFs.

  17. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  18. Peste des petits ruminants.

    PubMed

    Parida, S; Muniraju, M; Mahapatra, M; Muthuchelvan, D; Buczkowski, H; Banyard, A C

    2015-12-14

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants.

  19. Influence des interactions du couple ciment/adjuvant dispersant sur les proprietes des betons: Importance du mode d'introduction des adjuvants

    NASA Astrophysics Data System (ADS)

    Baalbaki, Moussa

    1998-12-01

    Les travaux de recherche de cette these de doctorat ont porte sur les phenomenes d'incompatibilite (ou de compatibilite) ciment/adjuvant dispersant en mettant l'accent sur l'influence du mode d'introduction des adjuvants sur les proprietes des betons frais et durcis. Les aspects physiques et chimiques de l'interaction ciment/adjuvant a ete relies aux proprietes des betons en tenant compte du rapport E/C, de la teneur en C3A du ciment ainsi que du type d'adjuvant dispersant. Le programme experimental propose debute par une etude rheologique et mecanique sur pate et sur beton. Le comportement du superplastifiant a base de polynaphtalene (PNS) depend surtout de son interaction avec les premiers produits d'hydratation du ciment. Cette interaction du superplastifiant PNS avec le ciment est remarquablement differente dans le cas ou l'ajout du PNS est differe de quelques minutes. Lorsque le superplastifiant PNS est introduit directement avec l'eau de gachage, on remarque la formation d'un gel blanc compose d'ettringite, de CaCO 3 et de polynaphtalene et ce compose organo-mineral est presque inexistant lorsque le superplastifiant PNS est ajoute en mode differe. Ce gel organo-mineral se forme a partir de la solution entre les aluminates de calcium hydrates, les sulfates et le PNS, et est responsable de la perte d'affaissement du beton. Les analyses au microscope electronique a balayage montrent que l'introduction du superplastifiant PNS en mode S1 (ajout direct) engendre la precipitation d'une plus grande quantite d'ettringite et de produit organo-mineral. Cette ettringite finement cristallisee, abondante et enchevetree aura pour consequence de diminuer les proprietes rheologiques des betons et des pates. Ce phenomene ne s'observe pas lorsque le superplastifiant PNS est introduit en mode differe. Le mode d'introduction du superplastifiant a base de polyacrylate (PAE) n'affecte nullement le comportement rheologique du beton. Par ailleurs, le gel organo-mineral n'apparait pas

  20. Music and the Nature: Input of the Czech Composers

    NASA Astrophysics Data System (ADS)

    Nemec, Vaclav; Nemcova, Lidmila

    2014-05-01

    Extraordinary occasions for art of any kind - music, creative graphic and plastic arts, literature (classic, modern incl. science fiction), theatre, cinema, etc. - exist to harmonise individual personal interests with those of the humanity well-being and of the Nature and also to cultivate individual spirituality and the appropriate values. Arts can be applied as irreplaceable means for making any human being better, for improving his sense for solidarity and for increasing his ethical sensibility. An interest for the art should be cultivated already since the childhood. - How much of inspiration for numerous composers all over the world has been given by the Nature, how much of inspiration for people who by listening to such a music are increasing nobility of their behaviour as well as their friendly approach to the Nature. - Many classical music works have been written with a strong inspiration by the Nature itself from the past until today. The actual Year of the Czech Music gives the possibility to present the most famous Czech composers inspired by the Nature (selected examples only): Bedřich Smetana (1824 - 1884): At the sea shore - a concert etude for piano inspired by his stay in Göteborg (Sweden); Vltava (Moldau) - a symphonic poem from the cycle "My country" inspired by the river crossing Bohemia from the South to Prague; From the Bohemian woods and meadows - another symphonic poem from the same cycle. Antonín Dvořák (1841 - 1904): V přírodě (In the Nature) - a work for orchestra Leoš Janáček (1854 - 1928): Příhody li\\vsky Bystrou\\vsky (The Cunning Little Vixen) - an opera situated mostly in a forest. Josef Bohuslav Foerster (1859-1951): Velké širé rodné lány (Big large native fields) - a choir for men singers inspired by the nature in the region where the composer as a boy from Prague was visiting his grand-father. Vítězslav Novák (1870 - 1949): In Tatra mountains - a symphonic poem expressing the author's passion for the famous

  1. Asymmetric wetting of patterned surfaces composed of intrinsically hysteretic materials.

    PubMed

    Anantharaju, Neeharika; Panchagnula, Mahesh V; Vedantam, Srikanth

    2009-07-07

    Wetting of chemically heterogeneous surfaces is modeled using a phase field theory. We focus on a chemically heterogeneous surface composed of squares of one component material embedded in another. Unlike previous studies where the component materials were characterized only by an equilibrium contact angle, in this paper each of the component materials is constitutively allowed to exhibit hysteresis. Using this approach, we investigate the effect of heterogeneity length scale on observed macroscopic behavior. Cassie theory is found to be applicable only in the limit of vanishing length scale. For surfaces with a finite heterogeneity length scale, the advancing and receding contact angles deviate from Cassie theory. We find that this deviation and its length scale dependence are asymmetric and depend on the wetting properties of the embedded material relative to the contiguous substrate.

  2. Ultrastructural analysis of an enterolith composed of deoxycholic acid.

    PubMed

    Iwamuro, Masaya; Miyashima, Yuichi; Yoshioka, Takahiro; Murata, Toshihiro; Miyabe, Yoshio; Kawai, Yoshinari; Urata, Haruo; Shiraha, Hidenori; Okada, Hiroyuki; Yamamoto, Kazuhide

    2014-12-01

    A 67-year-old Japanese man underwent enterotomy because of enterolith ileus. Component analysis by infrared spectroscopy revealed that the enterolith was composed of a high concentration of deoxycholic acid. We further analyzed and compared the ultrastructure of the enterolith and a commercially available powdered form of deoxycholic acid by means of scanning electron microscopy and energy dispersive X-ray spectroscopy. Energy dispersive X-ray spectroscopy analysis revealed that the ratios of carbon and oxygen in the enterolith were equal to those in the deoxycholic acid powder. Scanning electron microscopy analysis showed rectangular prism-shaped particles on the surface of the enterolith. This structure was similar to that of the deoxycholic acid powder. The surgically removed enterolith had a twisted and coiled appearance. Possible mechanisms underlying the formation of this unique form are discussed.

  3. Safer Design - Composable EHRs and Mechanisms for Safety.

    PubMed

    Senathirajah, Yalini

    2015-01-01

    As the deployment of health information technology progresses, issues of usability and safety, including the possibility of technology-induced errors have come to the fore. Increased complexity of care delivery models and emergent conditions such as the Ebola scare in the US point to the difficulty of design that allows for human cognitive limits while meeting complex needs. We previously described a modular composable approach to health information systems, which gives the end-user some control of design and allows for creation of systems meeting myriad and varied needs. Here we discuss how the different drag/drop interaction paradigm has implications for health IT safety via several mechanisms. These include display fragmentation and the need to changeably prioritize information elements, interruptions, fit to tasks and contexts, and rapid changeability allowing low-cost readjustments when lack of fit is found.

  4. Lyapunov instability of fluids composed of rigid diatomic molecules

    NASA Astrophysics Data System (ADS)

    Borzsák, István; Posch, H. A.; Baranyai, András

    1996-04-01

    We study the Lyapunov instability of a two-dimensional fluid composed of rigid diatomic molecules, with two interaction sites each, and interacting with a Weeks-Chandler-Anderson site-site potential. We compute full spectra of Lyapunov exponents for such a molecular system. These exponents characterize the rate at which neighboring trajectories diverge or converge exponentially in phase space. Qualitative different degrees of freedom, such as rotation and translation, affect the Lyapunov spectrum differently. We study this phenomenon by systematically varying the molecular shape and the density. We define and evaluate ``rotation numbers'' measuring the time averaged modulus of the angular velocities for vectors connecting perturbed satellite trajectories with an unperturbed reference trajectory in phase space. For reasons of comparison, various time correlation functions for translation and rotation are computed. The relative dynamics of perturbed trajectories is also studied in certain subspaces of the phase space associated with center-of-mass and orientational molecular motion.

  5. Second-order planar gradiometer composed of concentric superconductive loops

    SciTech Connect

    Kuriki, S.; Isobe, Y.; Mizutani, Y.

    1987-01-15

    A planar gradiometer composed of three concentric superconductive loops is analyzed. The gradiometer performs the second derivative with a rotational symmetry in a form of partial/sup 2/B/sub z//partialr/sup 2/, where r/sup 2/ = x/sup 2/+y/sup 2/. In response to the biomagnetic field generated by a current dipole, an isoflux line distribution which resembles well the magnetic field distribution is obtained. The location and the strength of the current-dipole source can readily be estimated from the isoflux pattern. Reduction of the magnetic field noise from distant sources with respect to the signal of a near source is calculated to be comparable with that of conventional axial gradiometers.

  6. Holographic material composed by dichromated gelatin with vanilla

    NASA Astrophysics Data System (ADS)

    Olivares-Perez, Arturo; Ortiz-Gutierrez, Mauricio; Arroyo-Correa, Gabriel; Ibarra, Juan C.; Fuentes-Tapia, Israel

    2003-05-01

    Dichromate gelatins are well known as good holographic materials. Now by doping this material with synthetic vanilla, a change in the spectral amplitude response is obtained. Due that the maximum absorption spectra from the dichromate ammonium is localized in UV region at λ = 390. With vanilla, the maximum spectral response is similar, exception for its optical density, reducing the exposure factor the order of 2 times. An important property with this mixture is the high resistance to humidity of the ambient. We have recorded some diffraciotn gratings, using the argon laser λ = 488 nm, which show good diffraction (grooves). A characteristic of the developed process is its simply, only using solution composed of water and isopropyl alcohol, this process takes approximately one hour.

  7. COMPOSE-HPC: A Transformational Approach to Exascale

    SciTech Connect

    Bernholdt, David E; Allan, Benjamin A.; Armstrong, Robert C.; Chavarria-Miranda, Daniel; Dahlgren, Tamara L.; Elwasif, Wael R; Epperly, Tom; Foley, Samantha S; Hulette, Geoffrey C.; Krishnamoorthy, Sriram; Prantl, Adrian; Panyala, Ajay; Sottile, Matthew

    2012-04-01

    The goal of the COMPOSE-HPC project is to 'democratize' tools for automatic transformation of program source code so that it becomes tractable for the developers of scientific applications to create and use their own transformations reliably and safely. This paper describes our approach to this challenge, the creation of the KNOT tool chain, which includes tools for the creation of annotation languages to control the transformations (PAUL), to perform the transformations (ROTE), and optimization and code generation (BRAID), which can be used individually and in combination. We also provide examples of current and future uses of the KNOT tools, which include transforming code to use different programming models and environments, providing tests that can be used to detect errors in software or its execution, as well as composition of software written in different programming languages, or with different threading patterns.

  8. Exocytotic fusion pores are composed of both lipids and proteins

    PubMed Central

    Bao, Huan; Goldschen-Ohm, Marcel; Jeggle, Pia; Chanda, Baron; Edwardson, J Michael; Chapman, Edwin R

    2016-01-01

    During exocytosis, fusion pores form the first aqueous connection that allows escape of neurotransmitters and hormones from secretory vesicles. Although it is well established that SNARE proteins catalyze fusion, the structure and composition of fusion pores remain unknown. Here, we exploited the rigid framework and defined size of nanodiscs to interrogate the properties of reconstituted fusion pores, using the neurotransmitter glutamate as a content-mixing marker. Efficient Ca2+-stimulated bilayer fusion, and glutamate release, occurred with approximately two molecules of mouse synaptobrevin 2 reconstituted into ~6-nm nanodiscs. The transmembrane domains of SNARE proteins assumed distinct roles in lipid mixing versus content release and were exposed to polar solvent during fusion. Additionally, tryptophan substitutions at specific positions in these transmembrane domains decreased glutamate flux. Together, these findings indicate that the fusion pore is a hybrid structure composed of both lipids and proteins. PMID:26656855

  9. Etude des Abondances de MG et de fe dans la Composante Stellaire des Disques des Galaxies Spirales

    NASA Astrophysics Data System (ADS)

    Beauchamp, Dominique

    Je presente ici une technique d'observation par imagerie des disques stellaires des galaxies spirales. Je tente, a l'aide d'un modele evolutif multiphase, de determiner les abondances de fer et de magnesium dans les disques. Dans ce but, je mesure les indices Mg2 et Fe5270 du systeme de Lick. Ces elements representent un choix judicieux d'indicateurs car ils sont formes par des supernovae de deux types differents ayant des durees de vie differentes. Le rapport d'abondances de ces deux elements est un indicateur du taux de formation des populations stellaires. Je decris, en premier lieu, les observations, la technique de mesure, ainsi que son application. J'analyse ensuite les indices mesures. A partir du modele multiphase, j'explore differents parametres physiques des spirales comme le taux de formation stellaire, l'evolution des abondances, les effets possibles de la presence de la barre, etc.

  10. Classification of 8 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    King, A.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; OâNeill, C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  11. Classification of 17 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Hoormann, J. K.; Asorey, J.; Carollo, D.; Moller, A.; Sharp, R.; Sommer, N. E.; Tucker, B. E.; Zhang, B.; Lidman, C.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Yuan, F.; Davis, T. M.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Lewis, G. F.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.

    2016-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  12. Classification of 13 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Sommer, N.; Tucker, B. E.; Moller, A.; Zhang, B.; Macualay, E.; Lidman, C.; Gshwend, J.; Martini, P.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.

    2016-09-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  13. Classification of 11 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Sharp, R.; Zhang, B.; Sommer, N. E.; Tucker, B. E.; Lidman, C.; Davis, T. M.; Asorey, J.; Mould, J.; Smith, M.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Carollo, D.; Moller, A.; Yuan, F.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Lewis, G. F.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2017-01-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  14. Classification of 2 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    O'Neill, C. R.; Moller, A.; Sommer, N. E.; Tucker, B. E.; Childress, M. J.; Lewis, G. F.; Lidman, C.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Gupta, R.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.

    2016-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  15. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  16. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  17. Classification of 14 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Tucker, B. E.; Sharp, R.; Yuan, F.; Zhang, B.; Lidman, C.; Davis, T. M.; Hinton, S.; Mould, J.; Smith, R. C.; Schubnell, M.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Castander, F. J.; Desai, S.; Paech, K.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey. The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  18. Classification of 4 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Glazebrook, K.; Amon, A.; Lidman, C.; Martini, P.; Tucker, B. E.; Yuan, F.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  19. Classification of 6 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  20. Classification of 15 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Tucker, B. E.; Lidman, C.; Martini, P.; Gshwend, Julia; Moller, A.; Zhang, B.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  1. Classification of 17 DES supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Mudd, D.; Martini, P.; Lewis, G. F.; Moller, A.; Sharp, R. G.; Sommer, N. E.; Tucker, B. E.; Yuan, F.; Zhang, B.; Asorey, J.; Davis, T. M.; Hinton, S.; Muthukrishna, D.; Parkinson, D.; Carnero, A.; King, A.; Lidman, C.; Webb, S.; Uddin, S.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; D'Andrea, C.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, M.; Prajs, S.; Smith, M.; Sullivan, M.; Maartens, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Gupta, R.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Papadopoulos, A.; Morganson, E.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2016-11-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  2. Latina Voices of Des Moines.

    ERIC Educational Resources Information Center

    Taylor, P. Dawn

    This dissertation examines the lives of Hispanic women living in Des Moines and includes their views of problems and opportunities involved in living in that city. Interviews were conducted with 24 Latino women over the age of 17 who had been in the area for over 2 years. Findings indicate that learning to speak English was the single most…

  3. Coaxial nanocable composed by imogolite and carbon nanotubes

    SciTech Connect

    Ramírez, M.; González, R. I.; Munoz, F.; Valdivia, J. A.; Rogan, J.; Kiwi, M.

    2015-12-31

    The discovery and development of Carbon Nanotubes (CNTs) at the beginning of the 1990s has driven a major part of solid state research. The electronic properties of the CNTs have generated a large number of ideas, as building coaxial nanocables. In this work we propose a possible type of such nanocables, which is formed by three nanostructures: two conducting CNTs, where one of them is covered by an insulator (an inorganic oxide nanotube: the imogolite aluminosilicate). The theoretical calculations were carried out using the density functional tight-binding formalism, by means of the DFTB+ code. This formalism allows to calculate the band structure, which compares favorably with DFT calculations, but with a significantly lower computational cost. As a first step, we reproduce the calculations of already published results, where the formation of a nanocable composed by one CNT and the imogolite as an insulator. Afterwards, we simulate the band structure for the proposed structure to study the feasibility of the coaxial nanocable. Finally, using classical MD simulations, we study the possible mechanisms of formation of these nanocables.

  4. Adult cutaneous hemangiomas are composed of nonreplicating endothelial cells.

    PubMed

    Tuder, R M; Young, R; Karasek, M; Bensch, K

    1987-12-01

    Thirty-four human "cherry" dermal hemangiomas were studied by electron microscopy, immunohistochemistry, and cell culture to assess the neoplastic nature of these lesions. Electron microscopy of nine hemangiomas revealed a pronounced thickening of the basement membrane (0.6 to 14 micron) in 93% of the total 158 vascular structures examined within the lesions. This increase was caused mainly by multiple layers of basal lamina, which were irregular in outline and frequently associated with pericytes. Basement membrane changes were present both in the periphery of the hemangiomas, as well as in the center of the lesions. Immature vessels could not be identified and mitoses were absent in all endothelial cells. Using an immunohistochemical marker (Ki67) specific for proliferating cells in G2 and S phases, positive staining was not found in the endothelial cells lining the hemangiomatous vessels, whereas basal epidermal keratinocytes in the same preparations and cultured microvascular endothelial cells expressed the antigen. Endothelial cells of nine hemangiomas did not stain with an activation-related antibody (E12) specific for endothelial cells. When endothelial cells from 14 hemangiomas were isolated and cultured under conditions that support the growth of normal human skin microvascular endothelial cells, the cells of hemangiomatous origin failed to grow. We conclude that the adult hemangiomas may not be true neoplasms, but a tissue overgrowth composed of mature vessels resembling dermal venules, lined by endothelial cells with virtually no turnover.

  5. Composable Analytic Systems for next-generation intelligence analysis

    NASA Astrophysics Data System (ADS)

    DiBona, Phil; Llinas, James; Barry, Kevin

    2015-05-01

    Lockheed Martin Advanced Technology Laboratories (LM ATL) is collaborating with Professor James Llinas, Ph.D., of the Center for Multisource Information Fusion at the University at Buffalo (State of NY), researching concepts for a mixed-initiative associate system for intelligence analysts to facilitate reduced analysis and decision times while proactively discovering and presenting relevant information based on the analyst's needs, current tasks and cognitive state. Today's exploitation and analysis systems have largely been designed for a specific sensor, data type, and operational context, leading to difficulty in directly supporting the analyst's evolving tasking and work product development preferences across complex Operational Environments. Our interactions with analysts illuminate the need to impact the information fusion, exploitation, and analysis capabilities in a variety of ways, including understanding data options, algorithm composition, hypothesis validation, and work product development. Composable Analytic Systems, an analyst-driven system that increases flexibility and capability to effectively utilize Multi-INT fusion and analytics tailored to the analyst's mission needs, holds promise to addresses the current and future intelligence analysis needs, as US forces engage threats in contested and denied environments.

  6. FIA: An Open Forensic Integration Architecture for Composing Digital Evidence

    NASA Astrophysics Data System (ADS)

    Raghavan, Sriram; Clark, Andrew; Mohay, George

    The analysis and value of digital evidence in an investigation has been the domain of discourse in the digital forensic community for several years. While many works have considered different approaches to model digital evidence, a comprehensive understanding of the process of merging different evidence items recovered during a forensic analysis is still a distant dream. With the advent of modern technologies, pro-active measures are integral to keeping abreast of all forms of cyber crimes and attacks. This paper motivates the need to formalize the process of analyzing digital evidence from multiple sources simultaneously. In this paper, we present the forensic integration architecture (FIA) which provides a framework for abstracting the evidence source and storage format information from digital evidence and explores the concept of integrating evidence information from multiple sources. The FIA architecture identifies evidence information from multiple sources that enables an investigator to build theories to reconstruct the past. FIA is hierarchically composed of multiple layers and adopts a technology independent approach. FIA is also open and extensible making it simple to adapt to technological changes. We present a case study using a hypothetical car theft case to demonstrate the concepts and illustrate the value it brings into the field.

  7. [Alexander Borodin--physician, chemist, scientist, teacher and composer].

    PubMed

    Vik, T

    1998-12-10

    Concert programmes and CD covers suggest that the Russian composer Alexander Borodin (1833-87) was also a great scientist. In this article we examine this proposition. Borodin was born in St. Petersburg as the illegitimate son of a Russian nobleman. As a boy his talents ranged from music to chemistry and languages. Borodin studied medicine at the Medico-Surgical Academy in St. Petersburg from 1850 to 1855 and defended his doctoral thesis on the similarity between arsenic and phosphoric acid in 1858. He did not, however, feel comfortable in his role as a doctor, and soon started to work as a chemist. In 1864 he was appointed professor of chemistry at the Medico-Surgical Academy. In 1861, Borodin attended the first international congress of chemistry in Karlsruhe, and he was among the founders of the Russian Chemical Society in 1868. He published 42 articles and was a friend of Dmitri Mendeleev, the scientist who described the periodic system. In 1872, Borodin started the first medical courses for women in Russia. It seems warranted to conclude that Alexander Borodin was indeed a great scientist and university teacher, though his immortality was earned by his leisure time activities.

  8. L'astronomie des Anciens

    NASA Astrophysics Data System (ADS)

    Nazé, Yaël

    2009-04-01

    Quelle que soit la civilisation à laquelle il appartient, l'être humain cherche dans le ciel des réponses aux questions qu'il se pose sur son origine, son avenir et sa finalité. Le premier mérite de ce livre est de nous rappeler que l'astronomie a commencé ainsi à travers les mythes célestes imaginés par les Anciens pour expliquer l'ordre du monde et la place qu'ils y occupaient. Mais les savoirs astronomiques passés étaient loin d'être négligeables et certainement pas limités aux seuls travaux des Grecs : c'est ce que l'auteur montre à travers une passionnante enquête, de Stonehenge à Gizeh en passant par Pékin et Mexico, fondée sur l'étude des monuments anciens et des sources écrites encore accessibles. Les tablettes mésopotamiennes, les annales chinoises, les chroniques médiévales, etc. sont en outre d'une singulière utilité pour les astronomes modernes : comment sinon remonter aux variations de la durée du jour au cours des siècles, ou percer la nature de l'explosion qui a frappé tant d'observateurs en 1054 ? Ce livre offre un voyage magnifiquement illustré à travers les âges, entre astronomie et archéologie.

  9. Multistatic Surveillance and Reconnaissance: Sensor, Signals and Data Fusion (Surveillance et Reconnaissance Multistatiques : Fusion des capteurs, des signaux et des donnees)

    DTIC Science & Technology

    2009-04-01

    capteurs , des signaux et des données) Research and Technology Organisation (NATO) BP 25, F-92201 Neuilly-sur-Seine Cedex, France RTO-EN-SET-133...Multistatiques : Fusion des capteurs , des signaux et des données) The material in this publication was assembled to support a Lecture Series under the...Surveillance et Reconnaissance Multistatiques : Fusion des capteurs , des signaux et des données (RTO-EN-SET-133) Synthèse Les systèmes radar

  10. Composable languages for bioinformatics: the NYoSh experiment.

    PubMed

    Simi, Manuele; Campagne, Fabien

    2014-01-01

    Language WorkBenches (LWBs) are software engineering tools that help domain experts develop solutions to various classes of problems. Some of these tools focus on non-technical users and provide languages to help organize knowledge while other workbenches provide means to create new programming languages. A key advantage of language workbenches is that they support the seamless composition of independently developed languages. This capability is useful when developing programs that can benefit from different levels of abstraction. We reasoned that language workbenches could be useful to develop bioinformatics software solutions. In order to evaluate the potential of language workbenches in bioinformatics, we tested a prominent workbench by developing an alternative to shell scripting. To illustrate what LWBs and Language Composition can bring to bioinformatics, we report on our design and development of NYoSh (Not Your ordinary Shell). NYoSh was implemented as a collection of languages that can be composed to write programs as expressive and concise as shell scripts. This manuscript offers a concrete illustration of the advantages and current minor drawbacks of using the MPS LWB. For instance, we found that we could implement an environment-aware editor for NYoSh that can assist the programmers when developing scripts for specific execution environments. This editor further provides semantic error detection and can be compiled interactively with an automatic build and deployment system. In contrast to shell scripts, NYoSh scripts can be written in a modern development environment, supporting context dependent intentions and can be extended seamlessly by end-users with new abstractions and language constructs. We further illustrate language extension and composition with LWBs by presenting a tight integration of NYoSh scripts with the GobyWeb system. The NYoSh Workbench prototype, which implements a fully featured integrated development environment for NYoSh is

  11. Composable languages for bioinformatics: the NYoSh experiment

    PubMed Central

    Simi, Manuele

    2014-01-01

    Language WorkBenches (LWBs) are software engineering tools that help domain experts develop solutions to various classes of problems. Some of these tools focus on non-technical users and provide languages to help organize knowledge while other workbenches provide means to create new programming languages. A key advantage of language workbenches is that they support the seamless composition of independently developed languages. This capability is useful when developing programs that can benefit from different levels of abstraction. We reasoned that language workbenches could be useful to develop bioinformatics software solutions. In order to evaluate the potential of language workbenches in bioinformatics, we tested a prominent workbench by developing an alternative to shell scripting. To illustrate what LWBs and Language Composition can bring to bioinformatics, we report on our design and development of NYoSh (Not Your ordinary Shell). NYoSh was implemented as a collection of languages that can be composed to write programs as expressive and concise as shell scripts. This manuscript offers a concrete illustration of the advantages and current minor drawbacks of using the MPS LWB. For instance, we found that we could implement an environment-aware editor for NYoSh that can assist the programmers when developing scripts for specific execution environments. This editor further provides semantic error detection and can be compiled interactively with an automatic build and deployment system. In contrast to shell scripts, NYoSh scripts can be written in a modern development environment, supporting context dependent intentions and can be extended seamlessly by end-users with new abstractions and language constructs. We further illustrate language extension and composition with LWBs by presenting a tight integration of NYoSh scripts with the GobyWeb system. The NYoSh Workbench prototype, which implements a fully featured integrated development environment for NYoSh is

  12. Active Control Technology for Enhanced Performance Operational Capabilities of Military Aircraft, Land Vehicles and Sea Vehicles (Technologies des systemes a commandes actives pour l’amelioration des performances operationnelles des aeronefs militaires, des vehicules terrestres et des vehicules maritimes)

    DTIC Science & Technology

    2001-06-01

    d’améliorer le comportement global des systèmes et des sous- systèmes. Il s’agit de matériaux intelligents, de technologies informatiques, de capteurs ...des servocommandes rapides et fiables, ainsi que des capteurs de fonctionnement fiable même dans des environnements défavorables, et en particulier...des sous-systèmes. Il s’agit de matériaux intelligents, de technologies de fabrication novatrices, de technologies informatiques, de capteurs et de

  13. Investigation de l'anisotropie du gap supraconducteur dans les composes Ba(Fe(1-x)Co(x))2As2, Ba(1-x)K(x)Fe2As2, LiFeAs et Fe1-deltaTe(1-x)Se(x)

    NASA Astrophysics Data System (ADS)

    Reid, Jean-Philippe

    ommaire La structure du gap supraconducteur et sa modulation sont intimement liees au potentiel d'interaction responsable de l'appariement des electrons d'un supraconducteur. Ainsi, l'etude de la structure du gap-SC et de sa modulation permettent de faire la lumiere sur la nature du mecanisme d'appariement des electrons. A cet egard, les resultats experimentaux des supraconducteurs a base de fer ne cadrent pas dans un seul ensemble, ce qui est en opposition au gap-SC universel des cuprates. Dans ce qui suit, nous presenterons une etude systematique du gap-SC pour plusieurs pnictides. En effet, en utilisant la conductivite thermique, une sonde directionnelle du gap-SC, nous avons ete en mesure de reveler la structure du gap-SC pour les composes suivants : Ba1-xKxFe 2As2, Ba(Fe1-xCo x)2As2, LiFeAs et Fe1-deltaTe 1-xSex. L'etude de ces quatre composes, de trois differentes familles structurales, a pu etablir un tableau partiel mais tres exhaustif de la structure du gap-SC de pnictides. En effet, tel qu'illustre dans cette these, ces quatre composes ne possedent aucun noeud dans leur structure du gap-SC a dopage optimal. Toutefois, a une concentration differente de celle optimale pour les composes K-Ba122 et Co-Ba122, des noeuds apparaissent sur la surface de Fermi, aux extremites 'du dome supraconducteur. Ceci suggere fortement que, pour ces composes, la presence de noeuds sur la surface de Fermi est nuisible a la phase supraconductrice. Mots-cles: Supraconducteurs a base de fer, Pnictides, Structure du gap supraconducteur, Conductivite thermique

  14. Évaluation des caractéristiques mécaniques du polissoir en polyuréthanne utilisé comme porte abrasifs durant le processus du polissage du verre optique

    NASA Astrophysics Data System (ADS)

    Aliouane, T.; Bouzid, D.; Belkhir, N.; Bouzid, S.; Herold, V.

    2005-05-01

    La fabrication des composants en verre optique nécessite des moyens de grande précision dans les procédés de finition vue l'importance accordée à leur qualité.
Durant le processus de polissage des verres optiques, le polissoir est un élément clé et a un impact direct sur les performances des composants optiques, non seulement il est utilisé comme support de grains abrasifs mais il doit posséder la fonction de transmission de la pression aux grains. La connaissance de ses propriétés, essentiellement mécanique, est impérative afin d'obtenir un état de surface optimal des composants optiques destinés à remplir des fonctions très précises dans des appareils optiques très performants.
Dans cette étude, nous avons constaté que les propriétés des polissoirs en polyuréthanne tel que la dureté, le module d'élasticité et la densité varient au cours du polissage. Ce changement a des effets sur l'état de surface de verre optique, causé par le changement microstructural de la surface du polissoir (distribution et dimensions des pores) et par conséquent sur la quantité des abrasifs (en oxyde de cérium) insérée dans les pores, ce qui influe sur la quantité de verre enlevée et sur l'état de surface du composant.
Sur la base des résultats obtenus, il a été prouvé que le polissoir subit des modifications très importantes ce qui influe considérablement sur son efficacité de polissage.

  15. Principles of moment distribution applied to stability of structures composed of bars or plates

    NASA Technical Reports Server (NTRS)

    Lundquist, Eugene E; Stowell, Elbridge Z; Schuette, Evan H

    1943-01-01

    Principles of the cross method of moment distribution, which have previously been applied to the stability of structures composed of bars under axial load, are applied to the stability of structures composed of long plates under longitudinal load.

  16. Signature spectrale des grains interstellaires.

    NASA Astrophysics Data System (ADS)

    Léger, A.

    Notre connaissance de la nature des grains interstellaires reposait sur un nombre très restreint de signatures spectrales dans la courbe d'extinction du milieu interstellaire. Une information considérable est contenue dans les 40 bandes interstellaires diffuses dans le visible, mais reste inexploitée. L'interprétation récente des cinq bandes IR en émission, en terme de molécules d'hydrocarbures aromatiques polycycliques, est développée. Elle permet l'utilisation d'une information spectroscopique comparable, à elle seule, à ce sur quoi était basée jusqu'alors notre connaissance de la matière interstellaire condensée. Différentes implications de cette mise en évidence sont proposées.

  17. Rethinking Joseph Janangelo's "Joseph Cornell and the Artistry of Composing Persuasive Hypertexts"

    ERIC Educational Resources Information Center

    College Composition and Communication, 2007

    2007-01-01

    This article presents several excerpts from an article written by Joseph Janangelo titled "Joseph Cornell and the Artistry of Composing Persuasive Hypertexts." In his article, Janangelo suggested that Cornell's work and ideas about composing model intelligent ways to composing persuasive nonsequential text. Janangelo also wondered if the use of…

  18. Writing in an Electronic Age: A Case Study of L2 Composing Processes

    ERIC Educational Resources Information Center

    Stapleton, Paul

    2010-01-01

    Studies on second language (L2) learners writing in English have found that composing is a recursive process requiring planning, formulating and revising. Of particular note among the many studies that have explored the composing processes of L2 writers are two characteristics: 1) They examine the composing processes of writers in real-time while…

  19. Trends, Vibes, and Energies: Building on Students' Strengths in Visual Composing

    ERIC Educational Resources Information Center

    Kurtyka, Faith

    2015-01-01

    This article examines the composing practices of two members of a social sorority who use visual images on the media of Tumblr and YouTube to teach potential new members about the kind of sorority experience they will have. From interviews with these composers and analyses of the artifacts they create, I distill three composing principles used to…

  20. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof. 303.24 Section 303.24 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF... and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  1. 16 CFR 303.24 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof. 303.24 Section 303.24 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF... and products composed thereof. The fiber content of pile fabrics or products composed thereof may...

  2. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    structure des oscillations de conductance en fonction du flux du champ magnétique de période h/e dont l'amplitude est beaucoup plus importante que celle mesurée sur un réseau carré de même dimension. Cette différence constitue une signature d'un effet de localisation induit par le champ magnétique sur la topologie mathcal{T}3. Pour des valeurs spécifiques du champ magnétique, du fait des interférences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limitée à un ensemble fini de cellule du réseau appelé cage. De la dépendance en température des oscillations de période h/e mesurées sur le réseau mathcal{T}3 nous avons tiré une longueur caractéristique qui peut être rattachée au périmètre des cages. Un phénomène inattendu fut l'observation, pour des champs magnétiques plus importants, d'un doublement de fréquence des oscillations. Ces oscillations de période h/2e pouvant avoir une amplitude supérieure aux oscillations de période h/e, une interprétation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur électrique des fils constituant le réseau et donc celle du nombre de canaux par brin a été étudiée en réalisant des grilles électrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont été mesurés.

  3. Impact de la preparation des anodes crues et des conditions de cuisson sur la fissuration dans des anodes denses

    NASA Astrophysics Data System (ADS)

    Amrani, Salah

    La fabrication de l'aluminium est realisee dans une cellule d'electrolyse, et cette operation utilise des anodes en carbone. L'evaluation de la qualite de ces anodes reste indispensable avant leur utilisation. La presence des fissures dans les anodes provoque une perturbation du procede l'electrolyse et une diminution de sa performance. Ce projet a ete entrepris pour determiner l'impact des differents parametres de procedes de fabrication des anodes sur la fissuration des anodes denses. Ces parametres incluent ceux de la fabrication des anodes crues, des proprietes des matieres premieres et de la cuisson. Une recherche bibliographique a ete effectuee sur tous les aspects de la fissuration des anodes en carbone pour compiler les travaux anterieurs. Une methodologie detaillee a ete mise au point pour faciliter le deroulement des travaux et atteindre les objectifs vises. La majorite de ce document est reservee pour la discussion des resultats obtenus au laboratoire de l'UQAC et au niveau industriel. Concernant les etudes realisees a l'UQAC, une partie des travaux experimentaux est reservee a la recherche des differents mecanismes de fissuration dans les anodes denses utilisees dans l'industrie d'aluminium. L'approche etait d'abord basee sur la caracterisation qualitative du mecanisme de la fissuration en surface et en profondeur. Puis, une caracterisation quantitative a ete realisee pour la determination de la distribution de la largeur de la fissure sur toute sa longueur, ainsi que le pourcentage de sa surface par rapport a la surface totale de l'echantillon. Cette etude a ete realisee par le biais de la technique d'analyse d'image utilisee pour caracteriser la fissuration d'un echantillon d'anode cuite. L'analyse surfacique et en profondeur de cet echantillon a permis de voir clairement la formation des fissures sur une grande partie de la surface analysee. L'autre partie des travaux est basee sur la caracterisation des defauts dans des echantillons d'anodes crues

  4. Conference Proceedings of the Meeting of the Structures and Materials Panel of AGARD (67th) on New Light Alloys, Held in Mierlo, Netherlands on 3-5 October 1988

    DTIC Science & Technology

    1989-08-01

    combat actuellement en cours de conception. A quelques, arnnees d’intervalle et en concurrence des materiaux precedenits. lea principaux producteurs...Technology Germany NASA Hq Washington DC 20546. USA SUB-COMMITTEE MEMBERS Chairman: Dr Paul Costa Directeur Scientifiquc des Materiaux ONERA 29 ave de...strength 2214-T6 1 0% 11% 7075-T731 * fatigue resistance 2024-T3 CP 276 high strength 7075 1 T66 - 8 % 11% 7010 or 7050 T76 *1strength-wise sexcluding ST

  5. Occupational Medicine Relevant to Aviation Medicine, Conference Proceedings of the Aerospace Medical Panel Symposium Held at London on 4 October 1983.

    DTIC Science & Technology

    1984-05-01

    give rise to physical symptoms after a certain period of ti- me. The seriousness of these symptoms depends on the individual resistance of the wor...COMPARATIVE CHEZ L’ANIMAL DE LA TOXICITE DES PRODUITS DE THERMOLYSE DE DIVERS MATERIAUX J.-P. DELCROIX - M. GUERBET LABORATOIRE CENTRAL DE BIOLOGIE AEROSPATIALE... materiaux presentant le minimum de toxicit6 en cas d’in- cendie dans une enceinte close et plus particulie rement A bord des aeronefs. Le6tude analytique

  6. Essais de capillarité et d'évaporation sous tomodensitométrie RX imagerie de la répartition de l'eau. Conséquences sur les flux et la localisation des zones de précipitation des sels

    NASA Astrophysics Data System (ADS)

    Géraud, Y.; Tournier, B.; Surma, F.; Mazerolle, F.

    2002-07-01

    La tomodensitométrie Rx est utilisée pour suivre la saturation et le séchage des pierres utilisées dans la construction de certains monuments. Les mesures d'atténuation des rayons X sont interprétées pour déterminer la répartition des phases minérales qui composent le matériau ainsi que la répartition de la porosité. Les essais de saturation ou de séchage effectués sous tomodensitométrie RX permettent de suivre les variations de saturation du réseau poreux au cours des essais. Les interfaces entre zones saturées en fluides et zones sèches localisent de possibles zones de précipitation de sels, processus important dans le dégradation de pierres d'œuvre.

  7. The Brain Functional State of Music Creation: an fMRI Study of Composers.

    PubMed

    Lu, Jing; Yang, Hua; Zhang, Xingxing; He, Hui; Luo, Cheng; Yao, Dezhong

    2015-07-23

    In this study, we used functional magnetic resonance imaging (fMRI) to explore the functional networks in professional composers during the creation of music. We compared the composing state and resting state imagery of 17 composers and found that the functional connectivity of primary networks in the bilateral occipital lobe and bilateral postcentral cortex decreased during the composing period. However, significantly stronger functional connectivity appeared between the anterior cingulate cortex (ACC), the right angular gyrus and the bilateral superior frontal gyrus during composition. These findings indicate that a specific brain state of musical creation is formed when professional composers are composing, in which the integration of the primary visual and motor areas is not necessary. Instead, the neurons of these areas are recruited to enhance the functional connectivity between the ACC and the default mode network (DMN) to plan the integration of musical notes with emotion.

  8. Composable Flexible Real-time Packet Scheduling for Networks on-Chip

    DTIC Science & Technology

    2012-05-16

    should not affect the behaviors of existing applications. In this paper , we propose a composable and flexible work-conserving packet scheduling...to be composable in the sense that new incoming applications should not affect the behaviors of existing applications. In this paper , we propose a...words, real-time flows need to be composable. We set this as the design goal for our packet scheduling discipline developed in this paper . B. Motivating

  9. Transition de phase quantique de type verrouillage-deverrouillage dans les canaux lineaires coherents des phases en rayures dans les doubles puits quantiques sous champ magnetique perpendiculaire

    NASA Astrophysics Data System (ADS)

    Faribault, Alexandre

    On peut creer un gaz electronique bidimensionnel en utilisant le potentiel de confinement d'une couche mince d'un semiconducteur dans un substrat fait d'une autre semiconducteur de gap plus eleve. L'ajout d'un champ magnetique perpendiculaire au plan de confinement modifie de facon drastique les proprietes du gaz electronique. Pour des densites et des valeurs du champ magnetique adequatement choisies, on obtient un etat fondamental en onde de densite de charge. Dans un systeme compose de deux de ces gaz bidimensionnels suffisamment rapproches l'un de l'autre, on prevoit theoriquement l'existence d'un etat fondamental compose d'une onde de densite de charge dans chacun des puits et d'une serie de regions lineaires ou l'on a une delocalisation coherente des electrons entre les deux puits. Dans cette these, on etudie le comportement a temperature nulle de cet etat fondamental en rayures coherentes. L'etude numerique des modes collectifs de ces phases laisse croire qu'un deverrouillage des canaux coherents est envisageable dans ce systeme. Afin d'etudier cette possibilite, nous construisons d'abord un modele effectif de canaux quasi-unidimensionnels couples qui permettent de reproduire correctement les excitations collectives a basse energie de la phase en rayures coherentes du double puits quantique. Dans un systeme de coordonnees adequatement choisi, ces excitations peuvent etre decrites par des ondes de pseudospin. Les parametres de ce modele effectif simple peuvent etre extraits des calculs des fonctions de reponse realises dans l'approximation Hartree-Fock dependante du temps (appelee aussi Generalized Random Phase Approximation). On constate l'efficacite de ce modele a decrire la dynamique basse energie du systeme pour une certaine plage de distances inter-puits. En retirant de ce modele les contributions a l'hamiltonien provenant des couplages de type Josephson entre les canaux, on obtient alors un systeme ou les canaux sont deverrouilles. Un traitement en

  10. Potentiel des images satellitaires multibandes a haute resolution spatiale pour la cartographie des componsants de l'eau en milieu cotier marin

    NASA Astrophysics Data System (ADS)

    Lavoie, Andre

    L'objectif principal que que nous poursuivons est de developper un modele de simulation du transfert radiatif eau-atmosphere adapte aux observations faites par le capteur Thematic Mapper (TM) de Landsat. Les informations que nous cherchons ont trait au milieu cotier marin et concernent les elements qui sont en suspension dans l'eau. Les images multibandes du capteur TM dans la partie visible du spectre, sont surtout visees par nos travaux. A la base de la simulation, nous utilisons un programme de simulation atmospherique, le code 6S, auquel nous greffons un modele de simulation du transfert radiatif dans la masse d'eau. Ce dernier estime le signal en fonction de 4 composants: l'eau, les pigments chlorophylliens (chlorophylle et phaeopigments), les matieres minerales et les substances organiques dissoutes. La concentration des differents composants sert de parametre d'entree pour definir le comportement optique de la masse d'eau. Le modele permet egalement de simuler une masse d'eau stratifiee si l'on connai t les concentrations des composants dans les differentes couches. Il inclut aussi la contribution du fond, selon sa nature et sa composition, ainsi que celle du miroitement du soleil et du ciel a la surface de l'eau. Les informations d'un echantillonnage de la masse d' eau synchronise avec le passage du satellite, a la baie des Chaleurs, d'une cartographie du couvert d'algues et d'un modele bathymetrique ont ete utilisees pour fixer les parametres de simulation par le modele. La comparaison montrent que le modele se comporte relativement bien surtout dans la bande TM2. Une erreur systematique de 2 valeurs numeriques en moyenne subsiste dans les trois bandes spectrales. Les resultats nous montrent que la visibilite du fond aux faibles profondeurs est un element tres important a considerer. Par ailleurs, l'analyse de sensibilite montre que les images TM sont plus sensibles aux concentrations en matieres minerales qu'aux pigments chlorophylliens et aux substances

  11. Ostéosynthèse des fractures des métacarpiens et des phalanges de la main par mini plaque: à propos de 12 cas

    PubMed Central

    Moncef, Erraji; Abdelhafid, Derfoufi; Abdessamad, Kharraji; Omar, Agoumi; Najib, Abdeljaouad; Abdelkrim, Daoudi; Hicham, Yacoubi

    2016-01-01

    Le traitement des fractures instables des métacarpes et des phalanges reste un objet de controverse. Peu de séries ont été rapportées dans la littérature, rendant leur analyse difficile. Nous rapportons une étude rétrospective comportant 12 patients, opérés par cette technique, ayant eu des fractures déplacées des métacarpes ou des phalanges, sur une période de deux ans. Les résultats globaux ont été bons dans 75% des cas, moyenne dans 16,5% des cas et mauvais dans 8,5% des cas. La stabilité du montage par mini plaques des fractures instables des métacarpiens et des phalanges ont permis une mobilisation précoce des articulations de la main, évitant ainsi la raideur. PMID:27800079

  12. Composing Science

    NASA Astrophysics Data System (ADS)

    Atkins, Leslie

    2015-03-01

    The course Scientific Inquiry at California State University was developed by faculty in biology, physics and English to meet ``writing proficiency'' requirements for non-science majors. Drawing from previous work in composition studies, the position that we take in this course is that we should be engaging students in writing that replicates the work that writing does in science, rather than replicating the particular structural conventions characteristic of scientific writing. That is, scientists use writing to have, remember, share, vet, challenge, and stabilize ideas, and our course requires students use writing to achieve those aims, rather than produce writing that obeys particular conventions of scientific writing. This talk will describe how we have integrated findings from composition studies with a course on scientific inquiry, and provide examples of how scientific communication has resulted from this dialogue. Funding by NSF #1140860.

  13. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Garments or products composed of or containing miscellaneous cloth scraps. 300.29 Section 300.29 Commercial Practices FEDERAL TRADE COMMISSION... Labeling § 300.29 Garments or products composed of or containing miscellaneous cloth scraps. (a) For...

  14. Multi-Draft Composing: An Iterative Model for Academic Argument Writing

    ERIC Educational Resources Information Center

    Eckstein, Grant; Chariton, Jessica; McCollum, Robb Mark

    2011-01-01

    Post-secondary writing teachers in composition and English as a second language (ESL) writing programs are likely familiar with multi-draft composing. Both composition and ESL writing programs share nearly identical multi-draft models despite the very unique and different cultures of each group. We argue that multi-draft composing as it is…

  15. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  16. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  17. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  18. 16 CFR 300.29 - Garments or products composed of or containing miscellaneous cloth scraps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (2) Where the product contains chiefly rayon as well as woolen fibers in the minimum percentage designated for recycled wool: Made of Miscellaneous Cloth Scraps Composed Chiefly of Rayon With Minimum of __% Recycled Wool. (3) Where the product is composed chiefly of a mixture of cotton and rayon as well as...

  19. Rethinking Composing in a Digital Age: Authoring Literate Identities through Multimodal Storytelling

    ERIC Educational Resources Information Center

    Vasudevan, Lalitha; Schultz, Katherine; Bateman, Jennifer

    2010-01-01

    In this article, the authors engage the theoretical lens of multimodality in rethinking the practices and processes of composing in classrooms. Specifically, they focus on how learning new composing practices led some fifth-grade students to author new literate identities--what they call authorial stances--in their classroom community. Their…

  20. Multimodal Composing in Classrooms: Learning and Teaching for the Digital World

    ERIC Educational Resources Information Center

    Miller, Suzanne M., Ed.; McVee, Mary B., Ed.

    2012-01-01

    Taking a close look at multimodal composing as an essential new literacy in schools, this volume draws from contextualized case studies across educational contexts to provide detailed portraits of teachers and students at work in classrooms. Authors elaborate key issues in transforming classrooms with student multimodal composing, including…

  1. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Pile fabrics and products composed thereof. 300.26 Section 300.26 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF... and products composed thereof. The fiber content of pile fabrics or products made thereof may...

  2. Making Judgements: Investigating the Process of Composing and Receiving Peer Feedback

    ERIC Educational Resources Information Center

    McConlogue, Teresa

    2015-01-01

    Recent studies have argued that tutor feedback is failing to support students' progression. The potential for peer feedback, i.e. feedback composed by peer assessors, to support learning has been under researched. The aim of this paper was to explore a case study of a peer assessor composing and receiving peer feedback. The paper reports a case…

  3. The Composer's World from Sketch to Score. LinkUp! 1998-99 Teacher's Guide.

    ERIC Educational Resources Information Center

    Hall, Randy L., Ed.

    This guide helps teachers and students examine the questions "Who are composers?" and "How do they compose?" In addition to the musical component of the inquiry, the guide also explores the world of writers and how they write and visual artists and how they create. Materials in the guide encourage students to express their…

  4. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat.

  5. Greening America's Capitals - Des Moines, IA

    EPA Pesticide Factsheets

    Report from Greening America's Capitals project in Des Moines, IA, to help the city enhance the 6th Avenue Corridor with pedestrian and bike improvements and green infrastructure to manage stormwater.

  6. Caracterisation pratique des systemes quantiques et memoires quantiques auto-correctrices 2D

    NASA Astrophysics Data System (ADS)

    Landon-Cardinal, Olivier

    Cette these s'attaque a deux problemes majeurs de l'information quantique: - Comment caracteriser efficacement un systeme quantique? - Comment stocker de l'information quantique? Elle se divise done en deux parties distinctes reliees par des elements techniques communs. Chacune est toutefois d'un interet propre et se suffit a elle-meme. Caracterisation pratique des systemes quantiques. Le calcul quantique exige un tres grand controle des systemes quantiques composes de plusieurs particules, par exemple des atomes confines dans un piege electromagnetique ou des electrons dans un dispositif semi-conducteur. Caracteriser un tel systeme quantique consiste a obtenir de l'information sur l'etat grace a des mesures experimentales. Or, chaque mesure sur le systeme quantique le perturbe et doit done etre effectuee apres avoir reprepare le systeme de facon identique. L'information recherchee est ensuite reconstruite numeriquement a partir de l'ensemble des donnees experimentales. Les experiences effectuees jusqu'a present visaient a reconstruire l'etat quantique complet du systeme, en particulier pour demontrer la capacite de preparer des etats intriques, dans lesquels les particules presentent des correlations non-locales. Or, la procedure de tomographie utilisee actuellement n'est envisageable que pour des systemes composes d'un petit nombre de particules. Il est donc urgent de trouver des methodes de caracterisation pour les systemes de grande taille. Dans cette these, nous proposons deux approches theoriques plus ciblees afin de caracteriser un systeme quantique en n'utilisant qu'un effort experimental et numerique raisonnable. - La premiere consiste a estimer la distance entre l'etat realise en laboratoire et l'etat cible que l'experimentateur voulait preparer. Nous presentons un protocole, dit de certification, demandant moins de ressources que la tomographie et tres efficace pour plusieurs classes d'etats importantes pour l'informatique quantique. - La seconde

  7. Une recension des écrits concernant la réalité psychoaffective des femmes ayant une vulvodynie : Difficultés rencontrées et stratégies développées

    PubMed Central

    Cantin-Drouin, Maude; Damant, Dominique; Turcotte, Daniel

    2008-01-01

    HISTORIQUE : Au cours des trois dernières décennies, une attention grandissante a été portée à l’étude du syndrome de vulvodynie, soit un inconfort vulvaire chronique inexpliqué, éprouvé en l’absence de pathologie précisée. En plus d’avoir des répercussions physiques, l’expérience de la vulvodynie comporte une dimension psychosociale. OBJECTIF : Cet article vise à faire une recension des écrits sur la réalité psychoaffective des femmes qui éprouvent une vulvodynie. MÉTHODE : Une recherche documentaire basée sur une exploration systématique de textes présentant des résultats de recherche et recensés dans les principales banques de données en sciences sociales, dont Dissertation Abstracts, Current Contents et PsycINFO, a été réalisée. RÉSULTATS : Cette recension des écrits révèle, malgré la présence de certains résultats divergents, que les femmes ayant une vulvodynie affrontent souvent des difficultés identitaires et psychologiques, qui sont influencées notamment par les normes sociales de sexualité et de féminité. Pour composer avec ces difficultés, les femmes développent différentes stratégies visant à diminuer le stress occasionné par la douleur et à améliorer leur bien-être psychologique. CONCLUSION : Les difficultés relationnelles et psychologiques vécues par les femmes ayant une vulvodynie ne découlent pas seulement de la douleur physique, mais aussi du sens qu’elles lui accordent, souvent influencé par les discours sociaux sur l’hétérosexualité et la féminité. Il importe donc d’intervenir auprès des femmes en tenant compte de l’influence du contexte social tout en poursuivant le développement des connaissances sur les aspects psychosociaux de cette expérience. PMID:18592063

  8. Evaluation of the Legibility for Characters Composed of Multiple Point Sources in Fog

    NASA Astrophysics Data System (ADS)

    Tsukada, Yuki; Toyofuku, Yoshinori; Aoki, Yoshiro

    The luminance conditions were investigated, at that the characters composed of multiple point sources were as legible as a character having a uniformly luminous surface in fog, in order to make the use of variable-message signs practical at airports. As the results, it was found that the thicker the fog or the higher the illuminance, the better the legibility of the point source characters become compared with the uniformly luminous surface characters. It is supposed that the ease of extracting each individual point source makes the characters composed of multiple point sources more legible even if their luminance is low. So the results show that if the conventional luminance standard is applied to the average luminance of a character composed of multiple point sources, a character composed of multiple point sources could be recognized without any degradation in legibility.

  9. The Composer's Program Note for Newly Written Classical Music: Content and Intentions.

    PubMed

    Blom, Diana M; Bennett, Dawn; Stevenson, Ian

    2016-01-01

    In concerts of western classical music the provision of a program note is a widespread practice dating back to the 18th century and still commonly in use. Program notes tend to inform listeners and performers about historical context, composer biographical details, and compositional thinking. However, the scant program note research conducted to date reveals that program notes may not foster understanding or enhance listener enjoyment as previously assumed. In the case of canonic works, performers and listeners may already be familiar with much of the program note information. This is not so in the case of newly composed works, which formed the basis of the exploratory study reported here. This article reports the views of 17 living contemporary composers on their writing of program notes for their own works. In particular, the study sought to understand the intended recipient, role and the content of composer-written program notes. Participating composers identified three main roles for their program notes: to shape a performer's interpretation of the work; to guide, engage or direct the listener and/or performer; and as collaborative mode of communication between the composer, performer, and listener. For some composers, this collaboration was intended to result in "performative listening" in which listeners were actively engaged in bringing each composition to life. This was also described as a form of empathy that results in the co-construction of the musical experience. Overall, composers avoided giving too much personal information and they provided performers with more structural information. However, composers did not agree on whether the same information should be provided to both performers and listeners. Composers' responses problematize the view of a program note as a simple statement from writer to recipient, indicating instead a more complex set of relations at play between composer, performer, listener, and the work itself. These relations are

  10. Effet Hall et Magnetisme des Alliages Amorphes Nickel-Zirconium Fabriques Par Pulverisation

    NASA Astrophysics Data System (ADS)

    Morel, Robert

    Cette these se situe dans le cadre d'une etude des proprietes electroniques et structurales des alliages metalliques amorphes, en cours depuis quelques annees a l'Universite de Montreal. Ce programme nous a entre autres amene a caracteriser la magnetoresistivite et l'effet Hall d'alliages FeZr, CoZr et NiZr, ce qui a permis de mettre en evidence deux caracteristiques de l'effet Hall: Dans les alliages amorphes ferromagnetiques, la resistivite elevee engendre un effet Hall extraordinaire beaucoup plus important que celui enregistre dans les metaux cristallins. La polarisation des spins entrai ne une asymetrie de la diffusion qui, tant dans les phases cristalline et amorphe, est tenue responsable de cette contribution. L'autre particularite du comportement de Hall de ces systemes est le renversement de signe du coefficient de Hall ordinaire, qui passe du negatif au positif dans les echantillons plus riches en zirconium. Dans les metaux cristallins, un modele d'electrons libres predit un signe negatif a moins que la conduction ne soit dominee par les trous. Or, dans un milieu desordonne les memes concepts sont difficilement applicables et de nouvelles theories ont du etre elaborees pour expliquer ce phenomene. Jusqu'a maintenant, l'etude des alliages amorphes nickel-zirconium s'est faite surtout a partir d'echantillons fabriques par trempe sur roue. Malheureusement cette technique ne permet pas la fabrication d'alliages contenant plus de 70% de nickel, a l'exception du seul compose Ni _{90}Zr_{10 }. Pour pallier a cette lacune et etendre nos connaissance a l'ensemble de la gamme de compositions, nous avons fabrique par pulverisation cathodique des echantillons NiZr amorphes--et quelques alliages cristallins tres riches en nickel--couvrant une bonne partie de la gamme interdite par la technique de trempe sur roue. Dans un premier temps, par comparaison avec les resultats connus nous avons mis en evidence les similitudes et les differences entre les alliages obtenus par

  11. Syphilis in composers and musicians--Mozart, Beethoven, Paganini, Schubert, Schumann, Smetana.

    PubMed

    Franzen, C

    2008-12-01

    In the pre-antibiotics era, syphilis was an extremely common disease. The first well-recorded European outbreak of what is now known as syphilis occurred in 1494, when it appeared among French troops besieging Naples. Thereafter, the disease spread all over Europe and, in the 18th and 19th centuries, many artists became victims of syphilis, among them poets, painters, philosophers, and musicians and composers. This review presents biographies of several musicians and composers that probably suffered from syphilis.

  12. Composability of partial-entanglement-breaking channels via entanglement-assisted local operations and classical communication

    NASA Astrophysics Data System (ADS)

    Namiki, Ryo

    2013-12-01

    We consider the composability of quantum channels from a limited amount of entanglement via local oper-ations and classical communication (LOCC). We show that any k-partial-entanglement-breaking channel can be composed from an entangled state with a Schmidt number of k via one-way LOCC. From the entanglement-assisted construction we can reach an alternative definition of partial-entanglement-breaking channels.

  13. In fatal pursuit of immortal fame: Peer competition and early mortality of music composers.

    PubMed

    Borowiecki, Karol Jan; Kavetsos, Georgios

    2015-06-01

    We investigate the impact of peer competition on longevity using a unique historical data set of 144 prominent music composers born in the 19th century. We approximate for peer competition measuring (a) the number or (b) the share of composers located in the same area and time, (c) the time spent in one of the main cities for classical music, and (d) the quality of fellow composers. These measures suggest that composers' longevity is reduced, if they located in agglomerations with a larger group of peers or of a higher quality. The point estimates imply that, all else equal, a one percent increase in the number of composers reduces composer longevity by ∼ 7.2 weeks. Our analysis showed that the utilized concentration measures are stronger than the personal factors in determining longevity, indicating that individuals' backgrounds have minimal impact on mitigating the effect of experienced peer pressure. The negative externality of peer competition is experienced in all cities, fairly independent of their population size. Our results are reaffirmed using an instrumental variable approach and are consistent throughout a range of robustness tests. In addition to the widely known economic benefits associated with competition, these findings suggest that significant negative welfare externalities exist as well.

  14. Positionsbestimmung des Unternehmens: Interne und externe Analyse

    NASA Astrophysics Data System (ADS)

    Bergmann, Lars; Crespo, Isabel; Portmann, Stefan

    Die Initiierung und Lenkung von Maßnahmen zur integrierten Modernisierung zielen auf die Verbesserung der Wettbewerbsfähigkeit eines Unternehmens ab. Damit diese Maßnahmen zielgerichtet die Wettbewerbsfähigkeit verbessern können, ist Wissen über die bestehende Wettbewerbsfähigkeit sowie über die bestehenden Fähigkeiten eine zentrale Voraussetzung. Eine zielgerichtete Auswahl problemadäquater Maßnahmen zur Verbesserung der Wettbewerbsfähigkeit bedarf daher im Vorfeld einer Bewertung der aktuellen Situation des Unternehmens im Sinne einer Positionsbestimmung. Erst wenn die internen Stärken und Schwächen sowie die externen Chancen und Risiken identifiziert sind, kann ein ganzheitliches Bild von der Position eines Unternehmens in seiner Umwelt gewonnen werden. Auf Basis der Kenntnisse über die Position des Unternehmens können anschließend zielgerichtet Maßnahmen ausgewählt werden, die einen Beitrag zur Verbesserung der Wettbewerbsfähigkeit des Unternehmens haben. Damit kommt der Positionsbestimmung als initialer Schritt des Prozesses der strategischen Unternehmensplanung eine zentrale Bedeutung im Rahmen der integrierten Modernisierung zu. Erfolgt die Auswahl von Maßnahmen ohne eine vorherige Positionsbestimmung, also lediglich auf Basis drängender Probleme, so besteht die Gefahr einer unbedachten und nur auf das "hier und heute“ bezogenen Schwerpunktbildung ohne Berücksichtigung der mittel- und langfristigen Ziele des Unternehmens.

  15. Micromechanical Behavior of Frictional Geologic Materials

    DTIC Science & Technology

    1988-11-01

    ranging from a suspension of particles to multicontacted particles forming a material with continuous force-deformation characteristics, i.e., a...Vol. 14, No. 4, pp. 25-38 (1974). 15. Biarez, J., "Contribution a l’Etude des Proprietes Mecaniques des Sols et des Materiaux Pulverulents," These de

  16. The Flight of Flexible Aircraft in Turbulence - State-of-the-Art in the Description and Modelling of Atmospheric Turbulence: Meeting of the Structures and Materials Panel of AGARD (64th) Held in Athens (Greece) on 28 September-3 October 1986

    DTIC Science & Technology

    1987-12-01

    Flights. Le Groupe de I’AGARD charge de I’etude des Structures et des Materiaux etudie actuellement le vol des avions flexibles dans les turbulences...D.O.F. FORCED OSC. ANGULAR OSCILLATION TRANSL. OSCILLATION SINGLE D.O.F. FREE OSC. FREE FLIGHT SEMI-FREE CONTROLLED MAGNETIC SUSPENSION

  17. Cross-Correlating DES and SPT

    NASA Astrophysics Data System (ADS)

    Baxter, Eric

    2017-01-01

    The Dark Energy Survey (DES) and the South Pole Telescope (SPT) provide a uniquely powerful combination of overlapping optical imaging and cosmic microwave background (CMB) data. Cross-correlations between DES and SPT are expected to arise from several physical effects, including gravitational lensing, the Sunyaev-Zel'dovich (SZ) effect, and the Integrated Sachs-Wolfe effect. The resultant correlations contain information not accessible to either experiment on its own. Measurement of these correlations offers several exciting possibilities, such as improved cosmological parameter constraints, improved understanding of systematics affecting the two experiments, and calibration of the masses of galaxy clusters at high redshift. In this talk I will summarize recent results obtained by cross-correlating early DES data with data from the SPT-SZ survey and will discuss prospects for future cross-correlation measurements with these two surveys.

  18. Dynamic DDES On DES Type Grid

    NASA Astrophysics Data System (ADS)

    Yin, Zifei; Durbin, Paul

    2014-11-01

    A dynamic procedure allows a DES formulation that we developed to adjustCDES for different flow configurations. Similarly to the dynamic Smagorinsky model, the grid is required to be fine enough to resolve a significant portion of the inertial range. In some cases, that requirement conflicts with the goal of DES to cut down computing cost. The current effort is therefore to determine a properCDES value by approximately recovering some unresolved small scales from primary, filtered solution. Repeated test filtering is adopted here to compute the approximation of the unfiltered solution. The formulation is based on the dynamicl2 w DDES model and different geometries with varies grid resolution are tested to determine the applicability of proposed formultion on DES type grids.

  19. Combined protein construct and synthetic gene engineering for heterologous protein expression and crystallization using Gene Composer

    SciTech Connect

    Raymond, Amy; Lovell, Scott; Lorimer, Don; Walchli, John; Mixon, Mark; Wallace, Ellen; Thompkins, Kaitlin; Archer, Kimberly; Burgin, Alex; Stewart, Lance

    2009-12-01

    With the goal of improving yield and success rates of heterologous protein production for structural studies we have developed the database and algorithm software package Gene Composer. This freely available electronic tool facilitates the information-rich design of protein constructs and their engineered synthetic gene sequences, as detailed in the accompanying manuscript. In this report, we compare heterologous protein expression levels from native sequences to that of codon engineered synthetic gene constructs designed by Gene Composer. A test set of proteins including a human kinase (P38{alpha}), viral polymerase (HCV NS5B), and bacterial structural protein (FtsZ) were expressed in both E. coli and a cell-free wheat germ translation system. We also compare the protein expression levels in E. coli for a set of 11 different proteins with greatly varied G:C content and codon bias. The results consistently demonstrate that protein yields from codon engineered Gene Composer designs are as good as or better than those achieved from the synonymous native genes. Moreover, structure guided N- and C-terminal deletion constructs designed with the aid of Gene Composer can lead to greater success in gene to structure work as exemplified by the X-ray crystallographic structure determination of FtsZ from Bacillus subtilis. These results validate the Gene Composer algorithms, and suggest that using a combination of synthetic gene and protein construct engineering tools can improve the economics of gene to structure research.

  20. Etude numerique et experimentale de la reponse vibro-acoustique des structures raidies a des excitations aeriennes et solidiennes

    NASA Astrophysics Data System (ADS)

    Mejdi, Abderrazak

    Les fuselages des avions sont generalement en aluminium ou en composite renforces par des raidisseurs longitudinaux (lisses) et transversaux (cadres). Les raidisseurs peuvent etre metalliques ou en composite. Durant leurs differentes phases de vol, les structures d'avions sont soumises a des excitations aeriennes (couche limite turbulente : TBL, champs diffus : DAF) sur la peau exterieure dont l'energie acoustique produite se transmet a l'interieur de la cabine. Les moteurs, montes sur la structure, produisent une excitation solidienne significative. Ce projet a pour objectifs de developper et de mettre en place des strategies de modelisations des fuselages d'avions soumises a des excitations aeriennes et solidiennes. Tous d'abord, une mise a jour des modeles existants de la TBL apparait dans le deuxieme chapitre afin de mieux les classer. Les proprietes de la reponse vibro-acoustique des structures planes finies et infinies sont analysees. Dans le troisieme chapitre, les hypotheses sur lesquelles sont bases les modeles existants concernant les structures metalliques orthogonalement raidies soumises a des excitations mecaniques, DAF et TBL sont reexamines en premier lieu. Ensuite, une modelisation fine et fiable de ces structures est developpee. Le modele est valide numeriquement a l'aide des methodes des elements finis (FEM) et de frontiere (BEM). Des tests de validations experimentales sont realises sur des panneaux d'avions fournis par des societes aeronautiques. Au quatrieme chapitre, une extension vers les structures composites renforcees par des raidisseurs aussi en composites et de formes complexes est etablie. Un modele analytique simple est egalement implemente et valide numeriquement. Au cinquieme chapitre, la modelisation des structures raidies periodiques en composites est beaucoup plus raffinee par la prise en compte des effets de couplage des deplacements planes et transversaux. L'effet de taille des structures finies periodiques est egalement pris en

  1. Étude par spectroscopie mécanique de l'interface dans des composites à matrice magnésium

    NASA Astrophysics Data System (ADS)

    Couteau, O.; Schaller, R.

    2003-03-01

    Des matériaux composites à matrice magnésium avec trois géométries de renfort différentes ont été étudiés par spectroscopie mécanique à l'aide d'un pendule de torsion en mode forcé. Ils ont été soumis à des cycles thermiques entre 100 K et 500K avec différentes vitesses de variation de température dot T et différentes fréquences d'excitation ω. Il est observé que le frottement intérieur résultant se décompose en une partie intrinsèque aux phases du matériau composite et une partie dépendant du paramètre dot T/ω. Cette dernière est reliée à la relaxation des contraintes thermiques créées à l'interface de tels matériaux à cause de la différence de coefficient de dilatation thermique entre matrice et renforts. Dans ce travail, le but est de déterminer quelle est l'influence de l'orientation des renforts sur la relaxation des contraintes thermiques.

  2. Note des Éditeurs scientifiques

    NASA Astrophysics Data System (ADS)

    Averbuch, P.

    Cette série d'articles est une revue de résultats expérimentaux sur différents "fluides" moléculaires, dans lesquels la cohésion est due à des forces de Van der Waals et à des liaisons hydrogène, l'eau étant un de ces fluides. Ces résultats sont présentés de façon à justifier expérimentalement un modèle original, non extensif, des propriétés de ces fluides, et l'ensemble se présente sous la forme de trois articles décrivant le modèle, suivis chacun par un article le comparant aux résultats expérimentaux publiés par de nombreux auteurs. Le caractère non extensif des propriétés physiques des fluides est choquant, contraire à beaucoup d'idées établies, il semble n'avoir en sa faveur qu'un argument, la comparaison avec un nombre de résultats expérimentaux assez grand pour que l'effet du hasard soit difficilement soupçonnable. En particulier, les écarts entre des résultats de mesures faits par des auteurs différents dans des conditions différentes sont expliqués, le sérieux et la compétence des différents expérimentateurs ne sont plus mis en doute : mais l'interprétation de ces résultats avec un modèle extensif non adapté est seule mise en cause. Les modèles extensifs étant utilisés systématiquement, au delà des expériences de physiciens, dans les calculs d'ingénieurs, et dans la modélisation d'appareils qui fonctionnent et de phénomènes naturels observés par tout le monde, il fallait expliquer pourquoi on pouvait renoncer à l'extensivité. Les raisons du succès pratique des modèles extensifs sont données, d'abord dans le cas des nématiques, puis dans celui des liquides ordinaires, et c'est ce qui rend l'ensemble cohérent, tant avec les mesures physiques fines qu'avec les observations quotidiennes. Il n'en reste pas moins que si l'interprétation donnée dans cette série d'articles est généralisable, une justification théorique du modèle utilisé devient nécessaire. Pour ce qui est des propriétés d

  3. Les applications des faisceaux d'ions dans la physique des polymères

    NASA Astrophysics Data System (ADS)

    Ratier, B.; Moliton, A.; Lucas, B.; Guille, B.; Clamadieu, M.

    1998-06-01

    Experimental configurations of ions beams are illustrated by diagrams in the case of low energy implantation, Reactive Ion Beam Etching (RIBE), Ion Beam Assisted Deposition (IBAD) of molecular layers (or oligomers). Nous présentons les configurations expérimentales (illustrées par des schémas) de trois applications des faisceaux d'ions au traitement physique des polymères : dopage par implantation (cité pour mémoire), gravure par faisceaux d'ions réactifs (RIBE), dépôt des couches moléculaires (ou oligomères) assistés par faisceau (IBAD).

  4. La structure des liquides simples et des alliages liquides métalliques

    NASA Astrophysics Data System (ADS)

    Simonet, V.; Bellissent, R.

    2003-09-01

    De par le caractère isotrope des interactions et leur courte portée, les liquides métalliques ont longtemps été considérés comme des systèmes modèles pouvant être décrits par un arrangement aléatoire de sphères dures. Ceci a été confirmé par l'allure des premières fonctions de distribution de paires déterminées par diffusion de RX ou de neutrons à la précision près des expériences de l'époque. Néanmoins, cette image a tout d'abord été révisée pour le cas des alliages métalliques dont les fonctions de distribution de paires ont révélé un ordre local plus complexe à cause des affinités chimiques entre espèces différentes. Grâce à la possibilité actuelle de mesurer des facteurs de structure de bien meilleure qualité, la question de la nature de l'ordre local et du degré d'isotropie des interactions peut se poser même dans le cas des liquides simples ou dans le cas d'alliages présentant à priori peu d'ordre chimique. Dans ce cadre, l'ordre local icosaédrique est particulièrement intéressant puisque l'icosaèdre est un agrégat très compact et, bien que présentant des liaisons directionnelles, très proche d'une configuration isotrope. La mise en évidence de ce type d'ordre local est présentée pour deux types de liquides : les liquides surfondus dans lesquels un ordre local icosaédrique a été prédit pour expliquer les propriétés de surfusion, et les liquides en équilibre avec des quasicristaux qui présentent un ordre local icosaédrique.

  5. Materials Substitution and Recycling. Proceedings of the Meeting of the Structures and Materials Panel (57th) Held at Vimeiro, Portugal on 14-19 October 1983.

    DTIC Science & Technology

    1984-04-01

    cognme ic premier choc petrobaer tie 1973. IFn mati~re de materiaux mitalliques aeronautiques. P’kvenement majeur a sans doutc Wt Is crise Zairoise de...ELEMENTS TRACES DANS LES SUPERALUIAGES par i.F.Wedier et J.Morlet 16 PROBLEMES POSES AUX MOTORISTES PAR LE RECYCLAGE DES MATERIAUX METALUIQUES pw...used In large amounts. Indeed, the development In ,outh Africa of a new family or weldable, corrosion- resistant alloys (termed 3C’N12 by Middleburg

  6. Helicopter Fatigue Design Guide

    DTIC Science & Technology

    1983-11-01

    de nouveaux materiaux ou technologies accentue I’importance que presente pour les forces de I’O.T.A.N. ce probleme de la maitrise des phenomenes de...fatigue interessant les helicopteres. La commission Structures et Materiaux de I’AGARD a ete conduite a proposer et developper une serie de reflexions...service life for the suspension components due to their vulnerabihty to darnage at high speeds. Spectrum No. 2 led to limitations being applied to

  7. Developpement des betons semi autoplacants a rheologie adaptee pour des infrastructures

    NASA Astrophysics Data System (ADS)

    Sotomayor Cruz, Cristian Daniel

    Au cours des dernières décennies, les infrastructures canadiennes et québécoises comportent plusieurs structures en béton armé présentant des problèmes de durabilité dus aux conditions climatiques sévères, à la mauvaise conception des structures, à la qualité des matériaux, aux types des bétons choisis, aux systèmes de construction ou à l'existence d'événements incontrôlables. En ce qui concerne le choix du béton pour la construction des infrastructures, une vaste gamme de béton divisée en deux principaux types peut être utilisée: le béton conventionnel vibré (BCV) et le béton autoplaçant (BAP). Dans le cas d'un BCV, la consolidation inadéquate par vibration a été un problème récurrent, occasionnant des dommages structuraux. Ceci a conduit à une réduction de la durabilité et à une augmentation du coût d'entretien et de réparation des infrastructures. Rien que l'utilisation d'un BAP a des avantages tels que l'élimination de la vibration, la réduction des coûts de main d'oeuvre et l'amélioration de la qualité des structures, néanmoins, le coût initial d'un BAP par rapport à un BCV ne permet pas encore de généraliser son utilisation dans l'industrie de la construction. Ce mémoire présente la conception d'une nouvelle gamme de béton semi-autoplaçant pour la construction des infrastructures (BSAP-I) exigeant une vibration minimale. Il s'agit de trouver un équilibre optimal entre la rhéologie et le coût initial du nouveau béton pour conférer une bonne performance structurale et économique aux structures. Le programme expérimental établi a premièrement permis d'évaluer la faisabilité d'utilisation des BSAP-I pour la mise en place des piliers d'une infrastructure de pont à Sherbrooke. En plus, l'utilisation d'un plan d'expériences a permis l'évaluation de trois paramètres de formulation sur les propriétés des mélanges de BSAP-I à l'état frais et durci. Finalement, l'évaluation de la performance des

  8. Musical tradition, insurrection, and resurrection: the life and legacy of composer/bassist Charles Mingus.

    PubMed

    St Louis, E K

    1999-01-01

    Charles Mingus was perhaps the foremost straight-ahead jazz upright bassist and composer of his generation, blending the inspirational influences of gospel, jazz improvisation, and art music leanings into a unique style all his own. His demise from amyotrophic lateral sclerosis (ALS) in his fifth decade robbed the world of one of the great creative voices of American music. Aspects of Mingus' life, his career as a bassist, bandleader, and composer, and his neuromuscular illness are discussed, emphasizing his legacy for the disparate fields of jazz and neurology.

  9. Quantum teleportation through an entangled state composed of displaced vacuum and single-photon states

    SciTech Connect

    Podoshvedov, S. A.

    2008-03-15

    We study a teleportation protocol of an unknown macroscopic qubit by means of a quantum channel composed of the displaced vacuum and single-photon states. The scheme is based on linear optical devices such as a beam splitter and photon number resolving detectors. A method based on conditional measurement is used to generate both the macroscopic qubit and entangled state composed from displaced vacuum and single-photon states. We show that such a qubit has both macroscopic and microscopic properties. In particular, we investigate a quantum teleportation protocol from a macroscopic object to a microscopic state.

  10. MO-A-BRD-05: Evaluation of Composed Lung Ventilation with 4DCT and Image Registration

    SciTech Connect

    Du, K; Bayouth, J; Reinhardt, J; Christensen, G; Zhao, B; Ding, K

    2014-06-15

    Purpose: Regional pulmonary function can be derived using fourdimensional computed tomography (4DCT) combined with deformable image registration. However, only peak inhale and exhale phases have been used thus far while the lung ventilation during intermediate phases is not considered. In our previous work, we have investigated the spatiotemporal heterogeneity of lung ventilation and its dependence on respiration effort. In this study, composed ventilation is introduced using all inspiration phases and compared to direct ventilation. Both methods are evaluated against Xe-CT derived ventilation. Methods: Using an in-house tissue volume preserving deformable image registration, unlike the direct ventilation method, which computes from end expiration to end inspiration, Jacobian ventilation maps were computed from one inhale phase to the next and then composed from all inspiration steps. The two methods were compared in both patients prior to RT and mechanically ventilated sheep subjects. In addition, they wereassessed for the correlation with Xe-CT derived ventilation in sheep subjects. Annotated lung landmarks were used to evaluate the accuracy of original and composed deformation field. Results: After registration, the landmark distance for composed deformation field was always higher than that for direct deformation field (0IN to 100IN average in human: 1.03 vs 1.53, p=0.001, and in sheep: 0.80 vs0.94, p=0.009), and both increased with longer phase interval. Direct and composed ventilation maps were similar in both sheep (gamma pass rate 87.6) and human subjects (gamma pass rate 71.9),and showed consistent pattern from ventral to dorsal when compared to Xe-CT derived ventilation. Correlation coefficient between Xe-CT and composed ventilation was slightly better than the direct method but not significant (average 0.89 vs 0.85, p=0.135). Conclusion: More strict breathing control in sheep subjects may explain higher similarity between direct and composed ventilation

  11. On architecting and composing engineering information services to enable smart manufacturing.

    PubMed

    Kulvatunyou, Boonserm Serm; Ivezic, Nenad; Srinivasan, Vijay

    2016-09-01

    Engineering information systems play an important role in the current era of digitization of manufacturing, which is a key component to enable smart manufacturing. Traditionally, these engineering information systems spanned the lifecycle of a product by providing interoperability of software subsystems through a combination of open and proprietary exchange of data. But research and development efforts are underway to replace this paradigm with engineering information services that can be composed dynamically to meet changing needs in the operation of smart manufacturing systems. This paper describes the opportunities and challenges in architecting such engineering information services and composing them to enable smarter manufacturing.

  12. Effets des electrons secondaires sur l'ADN

    NASA Astrophysics Data System (ADS)

    Boudaiffa, Badia

    Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire

  13. Fiabilité des structures mécaniques adaptatives: effet de la panne des actionneurs ou des capteurs sur la stabilité

    NASA Astrophysics Data System (ADS)

    Fall, H.; Charon, W.; Kouta, R.

    2002-12-01

    Ces dernières décennies, des activités significatives dans le monde étaient dirigées autour du contrôle actif. Le but de ces recherches était essentiellement d'améliorer les performances, la fiabilité et la sécurité des systèmes. Notamment dans le cas des structures soumises à des vibrations aléatoires. D'importants travaux ont été consacré à l'utilisation des “matériaux intelligents” comme capteurs et actionneurs. Cette article propose l'analyse de la fiabilité des systèmes mécaniques en étudiant les pannes des actionneurs ou des capteurs. L'effet de ces pannes sur la stabilité et la performance du système y est démontré. Les méthodologies de conception y sont rappelées. Des exemples numériques sont fournis à travers le contrôle d'un panneau sous chargement dynamique pour illustrer la méthode proposée.

  14. Propulsion and Energetics Panel Working Group 23 on Guide to the Measurement of the Transient Performance of Aircraft Turbine Engines and Components (Guide pour la mesure des performances en transitoire des turbomachines Aeronautiques et de leurs composants)

    DTIC Science & Technology

    1994-03-01

    measurement of pressures, temperatures, flows , component geometry including rotational speed and clearances, thnist, torque, and the use of the...Definitions of Measurcincnl Systems 4-1 4.2 Pressure 4-14 4.3 Temperature 4-6« 4.4 Flow 4-108 4.5 Geometry 4-170 4.6 Thrust and Torque 4-214 4.7...information on pressure, temper*- ture. fuel and air flow , geometry , fore« and lonpie, and control system panmeten. Generally a uniform format has

  15. The Nature of Children's Interactions while Composing Together on Computers. CIERA Report.

    ERIC Educational Resources Information Center

    Lomangino, Adrienne Gelpi; Nicholson, Julie; Sulzby, Elizabeth

    Patterns of interaction, including power relations and social goals, were investigated by observing first-grade children over a 5-month period as they worked in small groups to compose stories on the computer. Three groups selected for in-depth analysis represent the wide range of observed interaction patterns. Differences in interaction patterns…

  16. 16 CFR 300.26 - Pile fabrics and products composed thereof.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Pile fabrics and products composed thereof. 300.26 Section 300.26 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES AND REGULATIONS UNDER THE WOOL PRODUCTS LABELING ACT OF 1939 Labeling § 300.26 Pile...

  17. Improving Students' Memory for Musical Compositions and Their Composers: Mneme that Tune!

    ERIC Educational Resources Information Center

    Carney, Russell N.; Levin, Joel R.

    2007-01-01

    Students enrolled in music appreciation and music history courses may find it difficult to remember composers' names and the titles of their compositions--particularly when retrieval is prompted by corresponding classical music themes. We sought to develop and validate a mnemonic approach in which musical themes were first recoded as more concrete…

  18. Chinese Readers Can Perceive a Word Even When It's Composed of Noncontiguous Characters

    ERIC Educational Resources Information Center

    Ma, Guojie; Pollatsek, Alexander; Li, Yugang; Li, Xingshan

    2017-01-01

    This study explored whether readers could recognize a word composed of noncontiguous characters (a "cross-character word") in Chinese reading. All 3 experiments employed Chinese 4-character strings ABCD, where both AB and CD were 2-character words. In the cross-character word condition, AC was a word but in the control condition, AC was…

  19. The Organisation and Assessment of Composing at Key Stage 4 in English Secondary Schools

    ERIC Educational Resources Information Center

    Savage, Jonathan; Fautley, Martin

    2011-01-01

    This paper explores secondary school music teachers' current practice with regard to the organisation and assessment of composing at Key Stage 4. It draws on research undertaken on a nation-wide basis in England, via the use of two online surveys and face-to-face interviews. In terms of the organisation of classroom composition, the study found…

  20. Beyond Clara Schumann: Integrating Women Composers and Performers into General Music Classes

    ERIC Educational Resources Information Center

    Artesani, Laura

    2012-01-01

    To provide a comprehensive and balanced curriculum, the accomplishments of women composers and performers must be included in general music classes. This article addresses obstacles that have challenged women musicians and provides an outline for a unit that highlights seven American women who have achieved significant "firsts" in the world of…

  1. The Charlotte Civic Orchestra's Composer-in-the-Schools Project: Teaching Artistry in the Middle School

    ERIC Educational Resources Information Center

    Franklin, Elda

    2007-01-01

    This article describes the Composer-in-the-Schools Project, which successfully launched the Charlotte Civic Orchestra's Education and Outreach Program in a meaningful way by providing a unique opportunity for many young middle school orchestra students. Students who participated in the project, their parents, school administrators, and Charlotte…

  2. Creative Thinking for 21st Century Composing Practices: Creativity Pedagogies across Disciplines

    ERIC Educational Resources Information Center

    Lee, Sohui; Carpenter, Russell

    2015-01-01

    In this article, the authors explore the corpus of literature on creative thinking and applied creativity in higher education to help composition teacher-scholars and writing center practitioners improve the application of creativity in written, visual, and multimodal composing practices. From studies of creative thinking investigated across…

  3. A Particle Swarm Optimization Approach to Composing Serial Test Sheets for Multiple Assessment Criteria

    ERIC Educational Resources Information Center

    Yin, Peng-Yeng; Chang, Kuang-Cheng; Hwang, Gwo-Jen; Hwang, Gwo-Haur; Chan, Ying

    2006-01-01

    To accurately analyze the problems of students in learning, the composed test sheets must meet multiple assessment criteria, such as the ratio of relevant concepts to be evaluated, the average discrimination degree, difficulty degree and estimated testing time. Furthermore, to precisely evaluate the improvement of student's learning performance…

  4. The Composing Process: What We Know/What We Tell Our Students.

    ERIC Educational Resources Information Center

    Ede, Lisa S.

    Empirical and theoretical research and a teacher's own writing experience provide equally valuable resources in the composition classroom. Current research on the composing process suggests a conceptual change from that of a rigid sequence of clearly demarcated stages to a more recursive, hierarchically structured model. Until recently, the role…

  5. How to Compose, Write and Publish a Scientific or Professional Communication.

    PubMed

    Boranic, Milivoj

    2016-12-01

    There is an ample number of recommendations, guides and monographs addressing the art of composing and publishing written, oral or visual communications in science and various professions. In order to write an article, autors have to follow certain rules. Presentation of the article (oral or poster presentation) also requires skill, meaning that you have to fulfill certain guidelines and regulations.

  6. What Must Be Taught about Writing: Five Kinds of Knowledge and Five Kinds of Composing

    ERIC Educational Resources Information Center

    Wilhelm, Jeff, Ed.

    2012-01-01

    Students need to develop five kinds of knowledge to be successful in any kind of specific reading or writing task. These kinds of knowledge can be developed through five different kinds of composing that lead to deep understanding of how texts are constructed with specific content to create particular effects and meaning. Following this process…

  7. Tier 1 and Tier 2 Early Intervention for Handwriting and Composing

    ERIC Educational Resources Information Center

    Berninger, Virginia W.; Rutberg, Judith E.; Abbott, Robert D.; Garcia, Noelia; Anderson-Youngstrom, Marci; Brooks, Allison; Fulton, Cynthia

    2006-01-01

    Three studies evaluated Tier 1 early intervention for handwriting at a critical period for literacy development in first grade and one study evaluated Tier 2 early intervention in the critical period between third and fourth grades for composing on high stakes tests. The results contribute to knowledge of research-supported handwriting and…

  8. Transdisciplinary Dimensions in the Composing Activities of Children: Transfer of Strategies and Transformation of Knowledge

    ERIC Educational Resources Information Center

    Roels, Johanna Maria; Van Petegem, Peter

    2016-01-01

    Existing studies show the value of using visual expression as a means of teaching children to understand and create music. This study aspires to point out an additional valuable aspect, namely, the influence composing via visual expression--whereby children transform their own drawings--may have on children's subsequent compositional processes.…

  9. Children Composing and Their Visual-Spatial Approach to the Keyboard

    ERIC Educational Resources Information Center

    Roels, Johanna Maria; Van Petegem, Peter

    2015-01-01

    This study aims to contribute to the already existing findings of children's compositional strategies and products. Despite the abundance of research provided regarding the manner in which children approach composing, little has been found about how children deal, specifically, with the structure of the keyboard. Therefore, from a context in which…

  10. Flipping the Composing Process: Collaborative Drafting and Résumé Writing

    ERIC Educational Resources Information Center

    Anders, Abram

    2016-01-01

    This article argues for a flipped learning approach to business and professional communication composing processes. Flipped learning sequences can scaffold more robust engagement with prewriting activities and support opportunities for in-class collaborative and facilitated drafting exercises. These types of learning experiences offer numerous…

  11. Redesigning and Transforming: A Case Study of the Role of Semiotic Import in Early Composing Processes

    ERIC Educational Resources Information Center

    Ranker, Jason

    2009-01-01

    In this article, I explore the role of semiotic import (Van Leeuwen, 2005) in the composing processes of three bilingual students (six to seven years old) emerging as writers of English. Using social semiotic (Van Leeuwen, 2005) and design (New London Group, 2000) frameworks, I trace a qualitative "micro-history" of how the students imported…

  12. Facility Composer Design Wizards: A Method for Extensible Codified Design Logic Based on Explicit Facility Criteria

    DTIC Science & Technology

    2004-11-01

    36 22 Submittal worksheet for criterion 1.C7_1-1...Criteria Wizard Criteria Wizards are wizards that assist a user primarily in Planning Composer by providing one or more worksheets consisting of...for these criteria based on user input. Other Cri - teria Wizards currently under development include the Plumbing Fixture Calcu- lation Wizard and

  13. Multimodality: An Illuminating Approach to Unravelling the Complexities of Composing with ICT?

    ERIC Educational Resources Information Center

    Breeze, Nick

    2011-01-01

    Having previously been employed to investigate science and English classrooms and listening in the music classroom, theories of multimodality would appear to have much to contribute to an examination of group composing using Information and Communications Technology (ICT), owing to the multimodal nature of music software and group discourse. This…

  14. Weighted Maximum-a-Posteriori Estimation in Tests Composed of Dichotomous and Polytomous Items

    ERIC Educational Resources Information Center

    Sun, Shan-Shan; Tao, Jian; Chang, Hua-Hua; Shi, Ning-Zhong

    2012-01-01

    For mixed-type tests composed of dichotomous and polytomous items, polytomous items often yield more information than dichotomous items. To reflect the difference between the two types of items and to improve the precision of ability estimation, an adaptive weighted maximum-a-posteriori (WMAP) estimation is proposed. To evaluate the performance of…

  15. Audience Awareness in L1 and L2 Composing of Bilingual Writers.

    ERIC Educational Resources Information Center

    Zainuddin, Hanizah; Moore, Rashid A.

    2003-01-01

    Investigates how four bilingual writers from one culture attend to audience in persuasive writing in Malay and English, and the relationship between audience awareness, culture, and quality of their written products. Findings suggests individual differences between bilingual writer's use of audience strategies when composing were intertwined with…

  16. Let Cinderella and Luke Skywalker Help You Teach the Passe Compose and Imperfect.

    ERIC Educational Resources Information Center

    Terry, Robert M.

    Instructional materials for the passe compose and imperfect tenses in French use the technique of presenting familiar stories in the foreign language, written in the present tense, which students must place in the past by changing verb forms. The objective is to avoid the disadvantages of simply translating verb tenses and to allow the student to…

  17. Effects of high-fat diets composed of different oils on adipokine production in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dysregulation of adipokines is a hallmark of obesity. Polyunsaturated (n3) fatty acids in fish oil are shown to exert anti-inflammatory effects on adipose tissue mitigating the dysregulation of adipokines. In this study, we compared high-fat diets composed of different dietary oils with various le...

  18. Research as a Recursive Process: Reconsidering "The Composing Processes of Unskilled College Writers" 35 Years Later

    ERIC Educational Resources Information Center

    Perl, Sondra

    2014-01-01

    This article describes Sondra Perl's retrospective review of the composing processes of unskilled college writers and whether her assumptions and values in the designing of research projects have changed over her long teaching career. She uses her college dissertation "Five Writers Writing" as the basis to reflect on the authors and…

  19. Reading as Mediated and Mediating Action: Composing Meaning for Literature through Multimedia Interpretive Texts.

    ERIC Educational Resources Information Center

    Smagorinsky, Peter; O'Donnell-Allen, Cindy

    1998-01-01

    Analyzes the effort of a small group of high school seniors to interpret the character of Laertes in Shakespeare's "Hamlet" through a "body biography," a life-sized human outline they filled with images and words representing their understanding of the character. Examines their discussion as they composed their text. (PA)

  20. "Whistle for Willie," Lost Puppies, and Cartoon Dogs: The Sociocultural Dimensions of Young Children's Composing.

    ERIC Educational Resources Information Center

    Dyson, Anne Haas

    1992-01-01

    Argues that, even for young children, composing of both oral and written texts is sociocultural process. Highlights variation in kind of oral and written genres child uses, in kinds of discourse traditions child draws upon, and kind of relationships child author enacts with others. Discusses implications of sociocultural perspective on young…

  1. Author in the Arts: Composing and Collaborating in Text, Music, and the Visual Arts

    ERIC Educational Resources Information Center

    Gerben, Chris

    2015-01-01

    Many disciplines share similar terminology for making: creating, composing, writing, and authoring. The last term authoring, however, is problematic in how it privileges an end goal of individual authority and reward. To interrogate this term, and argue for its importance in future collaborative, interdisciplinary work, this article examines a…

  2. Spatial Stories with Nomadic Narrators: Affect, Snapchat, and Feeling Embodiment in Youth Mobile Composing

    ERIC Educational Resources Information Center

    Wargo, Jon M.

    2015-01-01

    While the vast majority of scholarship on mobile media, social semiotics, and multimodality highlights work done "behind" the screen, few studies have considered the embodied processes of youth composing "with" and "through" mobile technology. This study, drawn from a larger critical qualitative connective…

  3. How to Compose, Write and Publish a Scientific or Professional Communication

    PubMed Central

    Boranic, Milivoj

    2016-01-01

    There is an ample number of recommendations, guides and monographs addressing the art of composing and publishing written, oral or visual communications in science and various professions. In order to write an article, autors have to follow certain rules. Presentation of the article (oral or poster presentation) also requires skill, meaning that you have to fulfill certain guidelines and regulations. PMID:28077907

  4. Bending Elasticity Modulus of Giant Vesicles Composed of Aeropyrum Pernix K1 Archaeal Lipid

    PubMed Central

    Genova, Julia; Poklar Ulrih, Nataša; Kralj-Iglič, Veronika; Iglič, Aleš; Bivas, Isak

    2015-01-01

    Thermally induced shape fluctuations were used to study elastic properties of giant vesicles composed of archaeal lipids C25,25-archetidyl (glucosyl) inositol and C25,25-archetidylinositol isolated from lyophilised Aeropyrum pernix K1 cells. Giant vesicles were created by electroformation in pure water environment. Stroboscopic illumination using a xenon flash lamp was implemented to remove the blur effect due to the finite integration time of the camera and to obtain an instant picture of the fluctuating vesicle shape. The mean weighted value of the bending elasticity modulus kc of the archaeal membrane determined from the measurements meeting the entire set of qualification criteria was (1.89 ± 0.18) × 10−19 J, which is similar to the values obtained for a membrane composed of the eukaryotic phospholipids SOPC (1.88 ± 0.17) × 10−19 J and POPC (2.00 ± 0.21) × 10−19 J. We conclude that membranes composed of archaeal lipids isolated from Aeropyrum pernix K1 cells have similar elastic properties as membranes composed of eukaryotic lipids. This fact, together with the importance of the elastic properties for the normal circulation through blood system, provides further evidence in favor of expectations that archaeal lipids could be appropriate for the design of drug delivery systems. PMID:25821933

  5. Donkey Kong in Little Bear Country: A First Grader's Composing Development in the Media Spotlight.

    ERIC Educational Resources Information Center

    Dyson, Anne Haas

    2001-01-01

    Draws on data collected in an ethnographic project in an urban first grade to examine how media use informs child composing. Focuses on the influence of visual media involving animation. Concludes with a consideration of the teaching challenges posed, and opportunities offered, by the children's media use. (Author)

  6. Composing across Multiple Media: A Case Study of Digital Video Production in a Fifth Grade Classroom

    ERIC Educational Resources Information Center

    Ranker, Jason

    2008-01-01

    This is a qualitative case study of two students' composing processes as they developed a documentary video about the Dominican Republic in an urban, public middle school classroom. While using a digital video editing program, the students moved across multiple media (the Web, digital video, books, and writing), drawing semiotic resources from…

  7. Real-time rendering method and performance evaluation of composable 3D lenses for interactive VR.

    PubMed

    Borst, Christoph W; Tiesel, Jan-Phillip; Best, Christopher M

    2010-01-01

    We present and evaluate a new approach for real-time rendering of composable 3D lenses for polygonal scenes. Such lenses, usually called "volumetric lenses," are an extension of 2D Magic Lenses to 3D volumes in which effects are applied to scene elements. Although the composition of 2D lenses is well known, 3D composition was long considered infeasible due to both geometric and semantic complexity. Nonetheless, for a scene with multiple interactive 3D lenses, the problem of intersecting lenses must be considered. Intersecting 3D lenses in meaningful ways supports new interfaces such as hierarchical 3D windows, 3D lenses for managing and composing visualization options, or interactive shader development by direct manipulation of lenses providing component effects. Our 3D volumetric lens approach differs from other approaches and is one of the first to address efficient composition of multiple lenses. It is well-suited to head-tracked VR environments because it requires no view-dependent generation of major data structures, allowing caching and reuse of full or partial results. A Composite Shader Factory module composes shader programs for rendering composite visual styles and geometry of intersection regions. Geometry is handled by Boolean combinations of region tests in fragment shaders, which allows both convex and nonconvex CSG volumes for lens shape. Efficiency is further addressed by a Region Analyzer module and by broad-phase culling. Finally, we consider the handling of order effects for composed 3D lenses.

  8. Writing as Embodied, College Football Plays as Embodied: Extracurricular Multimodal Composing

    ERIC Educational Resources Information Center

    Rifenburg, J. Michael

    2014-01-01

    Recent explorations position multimodality as a largely curricular practice wherein the body typically is not figured as a potential mode of meaning making. Such a projection not only fails to acknowledge extracurricular uses of such a rhetoric but also fails to acknowledge the role of the body in and especially for composing. In hopes of…

  9. Reading during Sentence Composing and Error Correction: A Multilevel Analysis of the Influences of Task Complexity

    ERIC Educational Resources Information Center

    Van Waes, Luuk; Leijten, Marielle; Quinlan, Thomas

    2010-01-01

    In this study we investigated the role of reading, how writers coordinate editing with other writing processes. In particular, the experiment examines how the cognitive demands of sentence composing and the type of error influence the reading and writing performance. We devised an experimental writing task in which participants corrected an…

  10. Corrosion behaviour of materials at elevated temperatures in an oxidising atmosphere containing sulphur derivatives: influence of the compositon of aggressive phases and of the tested alloys. Final report. [Uranus S; Ni-5. 4Cr-3Al]. Tenue a la corrosion a temperature elevee de materiaux par les milieux oxydants contenant des derives soufres: influence de la composition des phases agressives et des alliages experimentes. rapport final

    SciTech Connect

    Cappelaere, M.; Lechaudel, R.; Turcot, G.

    1984-01-01

    Investigations on the resistance of Alloy 800, Uranus S, and Fe-Cr-Al (5.4% Cr, 3% Al) to sulphur dioxide have been carried out, considering three variables:- (1) duration of tests, (2) pressure of sulphur dioxide, and (3) concentration of bromine (10 and 100 x 10 to the minus 6 power by weight).

  11. Etude theorique et experimentale des evaporateurs de dioxyde de carbone operant dans des conditions de givrage

    NASA Astrophysics Data System (ADS)

    Bendaoud, Adlane Larbi

    Les evaporateurs de refrigeration sont surtout du type tube a ailettes, appeles serpentins, et fonctionnent dans l'une des conditions suivantes: seche, humide ou avec formation de givre. Il a ete demontre que la formation du givre sur la paroi exterieure de l'echangeur engendre une surconsommation energetique a cause des operations de degivrage puisque 15 a 20% seulement de la chaleur produite sert au degivrage tandis que le reste est dissipee dans l'environnement [1]. Avec l'avenement des nouveaux refrigerants, moins nocifs envers l'environnement, l'industrie du froid se trouve penalisee du fait que peu ou pas de composantes mecaniques (compresseur, pompe, echangeur...etc.) adaptees sont disponibles [3]. Il s'agit pour la communaute des frigoristes de combler ce retard technologique en redeveloppant ces composantes mecaniques afin qu'elles soient adaptees aux nouveaux refrigerants. Dans cette optique, et afin de mieux comprendre le comportement thermique des evaporateurs au CO2 fonctionnant dans des conditions seches, qu'un groupe de chercheurs du CanmetENERGIE avaient lance, en 2000, un programme de R & D. Dans le cadre de programme un outil de simulation des evaporateurs au CO2 a ete developpe et un banc d'essai contenant une boucle secondaire de refrigeration utilisant le CO2 comme refrigerant a ete construit. Comme continuite de ce travail de recherche, en 2006 ce meme groupe de recherche a lance un nouveau projet qui consiste a faire une etude theorique et experimentale des evaporateurs au CO2 operants dans des conditions de givrage. Et, c'est exactement dans le cadre de ce projet que se positionne ce travail de these. Ce travail de recherche a ete entrepris pour mieux comprendre le comportement thermique et hydrodynamique des serpentins fonctionnant dans des conditions de givrage, l'effet des circuits de refrigerant ainsi que celui des parametres geometriques et d'operation. Pour cela, un travail theorique supporte par une etude experimentale a ete effectue

  12. Determination des Parametres Atmospheriques des Etoiles Naines Blanches de Type DB

    NASA Astrophysics Data System (ADS)

    Beauchamp, Alain

    1995-01-01

    Les etoiles naines blanches dont les spectres visibles sont domines par des raies fortes d'helium neutre sont subdivisees en trois classes, DB (raies d'helium neutre seulement), DBA (raies d'helium neutre et d'hydrogene) et DBZ (raies d'helium neutre et d'elements lourds). Nous analysons trois echantillons de spectres observes de ces types de naines blanches. Les echantillons consistent, respectivement, de 48 spectres dans le domaine du visible (3700-5100 A). 24 dans l'ultraviolet (1200-3100 A) et quatre dans la partie rouge du visible (5100-6900) A). Parmi les objets de l'echantillon visible, nous identifions quatre nouvelles DBA, ainsi que deux nouvelles DBZ, auparavant classees DB. L'analyse nous permet de determiner spectroscopiquement les parametres atmospheriques, soit la temperature effective, la gravite de surface, ainsi que l'abondance relative de l'hydrogene, N(H)/N(He), dans le cas des DBA. Pour les objets plus chauds que ~15,000 K, la gravite de surface determinee est fiable, et nous obtenons les masses stellaires avec une relation masse -rayon theorique. Les exigences propres a l'analyse de ces objets ont requis d'importantes ameliorations dans la modelisation de leurs atmospheres et distributions de flux de radiation emis par ces derniers. Nous avons inclus dans les modeles d'atmospheres, pour la premiere fois a notre connaissance, les effets dus a la molecule He_sp{2 }{+}, ainsi que l'equation d'etat de Hummer et Mihalas (1988), qui tient compte des perturbations entre particules dans le calcul des populations des differents niveaux atomiques. Nous traitons la convection dans le cadre de la theorie de la longueur de melange. Trois grilles de modeles d'atmospheres a l'ETL (equilibre thermodynamique local) ont ete produites, pour un ensemble de temperatures effectives, gravites de surface et abondances d'hydrogene couvrant les proprietes des etoiles de nos echantillons; elles sont caracterisees par differentes parametrisations appelees, respectivement

  13. Profil epidemiologique des brulures d'enfants admis au Centre National des Brules, Maroc

    PubMed Central

    Zahid, A.; Atannaz, J.; Alaoui, M.; Rafik, A.; Ezzoubi, M.; Diouri, M.; Chlihi, A.; Bahechar, N.; Boukind, E.H.

    2011-01-01

    Summary Ce travail rétrospectif analyse les particularités épidémiologiques de 543 cas de brûlures d'enfants, représentant 45,7% des admissions de notre centre, en vue de déterminer les éléments pouvant contribuer à renforcer la prévention, qui reste le traitement de choix de cette pathologie. La moyenne d'âge est de 4,25 ans avec une prédilection pour la tranche d'âge d'un à cinq ans, avec 42,5% des cas. Une atteinte masculine est retrouvée dans 63,5% des cas. La brûlure survient à domicile dans 85,1% et accidentellement dans 95% des cas. Les brûlures thermiques représentent 96,5% des causes dominées par les liquides dans 69,3% des cas. La surface cutanée brûlée est ≥ 20% dans 52,3%. La brûlure intéresse essentiellement les membres supérieurs (79,1%). 56,8% des enfants sont transférés par d'autres hôpitaux et le délai de prise en charge hospitalière est supérieur à 6 heures dans 65,5%. Le taux de mortalité a été de 13,2%. PMID:22639559

  14. Modified hyperspheres algorithm to trace homotopy curves of nonlinear circuits composed by piecewise linear modelled devices.

    PubMed

    Vazquez-Leal, H; Jimenez-Fernandez, V M; Benhammouda, B; Filobello-Nino, U; Sarmiento-Reyes, A; Ramirez-Pinero, A; Marin-Hernandez, A; Huerta-Chua, J

    2014-01-01

    We present a homotopy continuation method (HCM) for finding multiple operating points of nonlinear circuits composed of devices modelled by using piecewise linear (PWL) representations. We propose an adaptation of the modified spheres path tracking algorithm to trace the homotopy trajectories of PWL circuits. In order to assess the benefits of this proposal, four nonlinear circuits composed of piecewise linear modelled devices are analysed to determine their multiple operating points. The results show that HCM can find multiple solutions within a single homotopy trajectory. Furthermore, we take advantage of the fact that homotopy trajectories are PWL curves meant to replace the multidimensional interpolation and fine tuning stages of the path tracking algorithm with a simple and highly accurate procedure based on the parametric straight line equation.

  15. Particle alignment and clustering in sheared granular materials composed of platy particles.

    PubMed

    Boton, Mauricio; Estrada, Nicolas; Azéma, Emilien; Radjaï, Farhang

    2014-11-01

    By means of molecular dynamics simulations, we investigate the texture and local ordering in sheared packings composed of cohesionless platy particles. The morphology of large packings of platy particles in quasistatic equilibrium is complex due to the combined effects of local nematic ordering of the particles and anisotropic orientations of contacts between particles. We find that particle alignment is strongly enhanced by the degree of platyness and leads to the formation of face-connected clusters of exponentially decaying size. Interestingly, due to dynamics in continuous shearing, this ordering phenomenon emerges even in systems composed of particles of very low platyness differing only slightly from spherical shape. The number of clusters is an increasing function of platyness. However, at high platyness the proportion of face-face interactions is too low to allow for their percolation throughout the system.

  16. Transparency windows of the plasmonic nanostructure composed of C-shaped and U-shaped resonators

    NASA Astrophysics Data System (ADS)

    Zhou, Xin; Ouyang, Min; Tang, Bin; Wang, Zhibing; He, Jun

    2017-02-01

    We in this study investigated numerically the plasmon-induced transparency (PIT) effect on the plasmonic nanostructures composed of C-shaped and U-shaped resonators by using finite difference time domain (FDTD) method. The PIT effect in the nanosystem stemmed from the near field coupling between the bright and dark modes. The nanostructure composed of three resonators exhibited double PIT effect. And the PIT spectral response of the proposed nanostructures was demonstrated having a dependence on the parameters of the compound plasmonic system such as the widths of C-shaped resonator and U-shaped resonator, the resonators spatial arrangement and the edge-to-edge distance between the adjacent resonators. The electric and magnetic field distributions of certain resonance wavelengths were also given to discuss the underlying physics. The resonator design strategy opens up a rich pathway to develop the building block of systems for all optical switching, plasmonic sensing applications.

  17. Optical memory development. Volume 3: The membrane light value page composer

    NASA Technical Reports Server (NTRS)

    Cosentino, L. S.; Nagle, E. M.; Stewart, W. C.

    1972-01-01

    The feasibility of producing a page composer for optical memory systems using thin, deformable, membrane-mirror elements as light valves was investigated. The electromechanical and optical performances of such elements were determined both analytically and experimentally. It was found that fast switching (approximately 10 microseconds), high-contrast (10 or greater), fatigue-free operation over missions of cycles, and efficient utilization of input light could be obtained with membrane light valves. Several arrays of 64 elements were made on substrates with feedthroughs, allowing access to individual elements from the backside of the substrate. Single light valves on such arrays were successfully operated with the transistors designed and produced for selection and storage at each bit location. This simulated the operation of a prototype page composer with semiconductor chips beam-lead bonded to the back of the substrate.

  18. PepComposer: computational design of peptides binding to a given protein surface

    PubMed Central

    Obarska-Kosinska, Agnieszka; Iacoangeli, Alfredo; Lepore, Rosalba; Tramontano, Anna

    2016-01-01

    There is a wide interest in designing peptides able to bind to a specific region of a protein with the aim of interfering with a known interaction or as starting point for the design of inhibitors. Here we describe PepComposer, a new pipeline for the computational design of peptides binding to a given protein surface. PepComposer only requires the target protein structure and an approximate definition of the binding site as input. We first retrieve a set of peptide backbone scaffolds from monomeric proteins that harbor the same backbone arrangement as the binding site of the protein of interest. Next, we design optimal sequences for the identified peptide scaffolds. The method is fully automatic and available as a web server at http://biocomputing.it/pepcomposer/webserver. PMID:27131789

  19. Towards Composing Data Aware Systems Biology Workflows on Cloud Platforms: A MeDICi-based Approach

    SciTech Connect

    Gorton, Ian; Liu, Yan; Yin, Jian; Kulkarni, Anand V.; Wynne, Adam S.

    2011-09-08

    Cloud computing is being increasingly adopted for deploying systems biology scientific workflows. Scientists developing these workflows use a wide variety of fragmented and competing data sets and computational tools of all scales to support their research. To this end, the synergy of client side workflow tools with cloud platforms is a promising approach to share and reuse data and workflows. In such systems, the location of data and computation is essential consideration in terms of quality of service for composing a scientific workflow across remote cloud platforms. In this paper, we describe a cloud-based workflow for genome annotation processing that is underpinned by MeDICi - a middleware designed for data intensive scientific applications. The workflow implementation incorporates an execution layer for exploiting data locality that routes the workflow requests to the processing steps that are colocated with the data. We demonstrate our approach by composing two workflowswith the MeDICi pipelines.

  20. Modified Hyperspheres Algorithm to Trace Homotopy Curves of Nonlinear Circuits Composed by Piecewise Linear Modelled Devices

    PubMed Central

    Vazquez-Leal, H.; Jimenez-Fernandez, V. M.; Benhammouda, B.; Filobello-Nino, U.; Sarmiento-Reyes, A.; Ramirez-Pinero, A.; Marin-Hernandez, A.; Huerta-Chua, J.

    2014-01-01

    We present a homotopy continuation method (HCM) for finding multiple operating points of nonlinear circuits composed of devices modelled by using piecewise linear (PWL) representations. We propose an adaptation of the modified spheres path tracking algorithm to trace the homotopy trajectories of PWL circuits. In order to assess the benefits of this proposal, four nonlinear circuits composed of piecewise linear modelled devices are analysed to determine their multiple operating points. The results show that HCM can find multiple solutions within a single homotopy trajectory. Furthermore, we take advantage of the fact that homotopy trajectories are PWL curves meant to replace the multidimensional interpolation and fine tuning stages of the path tracking algorithm with a simple and highly accurate procedure based on the parametric straight line equation. PMID:25184157

  1. Composable Security Proof for Continuous-Variable Quantum Key Distribution with Coherent States

    NASA Astrophysics Data System (ADS)

    Leverrier, Anthony

    2015-02-01

    We give the first composable security proof for continuous-variable quantum key distribution with coherent states against collective attacks. Crucially, in the limit of large blocks the secret key rate converges to the usual value computed from the Holevo bound. Combining our proof with either the de Finetti theorem or the postselection technique then shows the security of the protocol against general attacks, thereby confirming the long-standing conjecture that Gaussian attacks are optimal asymptotically in the composable security framework. We expect that our parameter estimation procedure, which does not rely on any assumption about the quantum state being measured, will find applications elsewhere, for instance, for the reliable quantification of continuous-variable entanglement in finite-size settings.

  2. Photonic band structure of one-dimensional aperiodic superlattices composed of negative refraction metamaterials

    NASA Astrophysics Data System (ADS)

    Tyc, Michał H.; Salejda, Włodzimierz; Klauzer-Kruszyna, Agnieszka; Tarnowski, Karol

    2007-05-01

    The dispersion relation for polarized light transmitting through a one-dimensional superlattice composed of aperiodically arranged layers made of ordinary dielectric and negative refraction metamaterials is calculated with finite element method. Generalized Fibonacci, generalized Thue-Morse, double-periodic and Rudin-Shapiro superlattices are investigated, using their periodic approximants. Strong dispersion of metamaterials is taken into account. Group velocities and effective refraction indices in the structures are calculated. The self-similar structure of the transmission spectra is observed.

  3. The music of war: Seven World War 1 composers and their experience of combat.

    PubMed

    Davidson, Jonathan Rt

    2016-09-28

    The effect of World War 1 military service on composers has been neglected in comparison with poets and artists. This article describes the wartime service of Arthur Bliss, Ralph Vaughan Williams, Ivor Gurney, EJ Moeran, Gordon Jacob, Patrick Hadley, and Maurice Ravel. The relationship between experiences of combat and the psychological health of these men is examined, with consideration being given to predisposition and possible causative influences of military service on their later careers, examined from individual and societal perspectives.

  4. Gene Composer: database software for protein construct design, codon engineering, and gene synthesis

    PubMed Central

    Lorimer, Don; Raymond, Amy; Walchli, John; Mixon, Mark; Barrow, Adrienne; Wallace, Ellen; Grice, Rena; Burgin, Alex; Stewart, Lance

    2009-01-01

    Background To improve efficiency in high throughput protein structure determination, we have developed a database software package, Gene Composer, which facilitates the information-rich design of protein constructs and their codon engineered synthetic gene sequences. With its modular workflow design and numerous graphical user interfaces, Gene Composer enables researchers to perform all common bio-informatics steps used in modern structure guided protein engineering and synthetic gene engineering. Results An interactive Alignment Viewer allows the researcher to simultaneously visualize sequence conservation in the context of known protein secondary structure, ligand contacts, water contacts, crystal contacts, B-factors, solvent accessible area, residue property type and several other useful property views. The Construct Design Module enables the facile design of novel protein constructs with altered N- and C-termini, internal insertions or deletions, point mutations, and desired affinity tags. The modifications can be combined and permuted into multiple protein constructs, and then virtually cloned in silico into defined expression vectors. The Gene Design Module uses a protein-to-gene algorithm that automates the back-translation of a protein amino acid sequence into a codon engineered nucleic acid gene sequence according to a selected codon usage table with minimal codon usage threshold, defined G:C% content, and desired sequence features achieved through synonymous codon selection that is optimized for the intended expression system. The gene-to-oligo algorithm of the Gene Design Module plans out all of the required overlapping oligonucleotides and mutagenic primers needed to synthesize the desired gene constructs by PCR, and for physically cloning them into selected vectors by the most popular subcloning strategies. Conclusion We present a complete description of Gene Composer functionality, and an efficient PCR-based synthetic gene assembly procedure with mis

  5. Hydration characteristics and environmental friendly performance of a cementitious material composed of calcium silicate slag.

    PubMed

    Zhang, Na; Li, Hongxu; Zhao, Yazhao; Liu, Xiaoming

    2016-04-05

    Calcium silicate slag is an alkali leaching waste generated during the process of extracting Al2O3 from high-alumina fly ash. In this research, a cementitious material composed of calcium silicate slag was developed, and its mechanical and physical properties, hydration characteristics and environmental friendly performance were investigated. The results show that an optimal design for the cementitious material composed of calcium silicate slag was determined by the specimen CFSC7 containing 30% calcium silicate slag, 5% high-alumina fly ash, 24% blast furnace slag, 35% clinker and 6% FGD gypsum. This blended system yields excellent physical and mechanical properties, confirming the usefulness of CFSC7. The hydration products of CFSC7 are mostly amorphous C-A-S-H gel, rod-like ettringite and hexagonal-sheet Ca(OH)2 with small amount of zeolite-like minerals such as CaAl2Si2O8·4H2O and Na2Al2Si2O8·H2O. As the predominant hydration products, rod-like ettringite and amorphous C-A-S-H gel play a positive role in promoting densification of the paste structure, resulting in strength development of CFSC7 in the early hydration process. The leaching toxicity and radioactivity tests results indicate that the developed cementitious material composed of calcium silicate slag is environmentally acceptable. This study points out a promising direction for the proper utilization of calcium silicate slag in large quantities.

  6. Fundamental Characteristics of Inflatable Structure Composed of Sealed Multi-Cells

    NASA Astrophysics Data System (ADS)

    Ishimura, Kosei; Higuchi, Ken

    Inflatable structure is an attractive candidate as ultra-light space structures with high packaging efficiency. They consist of flexible membrane and some components for the deployment. For such pneumatic structure with membrane, the damage of the membrane caused by space debris is one of serious problems for the utilization in space. To solve the problem, multi-cellular inflatable structures are proposed. Inflatable structures composed of multi-cells are robust against the damage of membrane. In this paper, a new type of inflatable cylinder which is composed of sealed multi-cells was investigated. Because deployment of the structure can be driven by the gas pressure of the sealed multi-cells, no complex components such as gas tanks and electric valves are required for the deployment. The fundamental characteristics of the deployment are investigated experimentally. As a result, it is shown that the inflatable cylinder composed of sealed multi-cells can achieve the deployment with simple hold-release mechanism even though some cells are damaged. Furthermore, by applying with inner bellows and outside constraint wires, the deployment sequence can be controlled and almost straight deployment can be realized.

  7. Constructing three-dimensional detachable and composable computer models of the head and neck.

    PubMed

    Fan, Min; Dai, Peishan; Zheng, Buhong; Li, Xinchun

    2015-06-01

    The head and neck region has a complex spatial and topological structure, three-dimensional (3D) computer model of the region can be used in anatomical education, radiotherapy planning and surgical training. However, most of the current models only consist of a few parts of the head and neck, and the 3D models are not detachable and composable. In this study, a high-resolution 3D detachable and composable model of the head and neck was constructed based on computed tomography (CT) serial images. First, fine CT serial images of the head and neck were obtained. Then, a color lookup table was created for 58 structures, which was used to create anatomical atlases of the head and neck. Then, surface and volume rendering methods were used to reconstruct 3D models of the head and neck. Smoothing and polygon reduction steps were added to improve 3D rendering effects. 3D computer models of the head and neck, including the sinus, pharynx, vasculature, nervous system, endocrine system and glands, muscles, bones and skin, were reconstructed. The models consisted of 58 anatomical detachable and composable structures and each structure can be displayed individually or together with other structures.

  8. A Review of Crashworthiness of Composite Aircraft Structures

    DTIC Science & Technology

    1990-02-01

    CRASHWORTHINESS OF COMPOSITE AIRCRAFT STRUCTURES ETUDE SUR LA RESISTANCE A L’ECRASEMENT DES STRUCTURES D’AERONEF EN MATERIAUX COMPOSITES by/par C. Poon...menses en Am~rique du Nord sur la resistance A l16crasement des structures d’a~ronef en materiaux composites a 06 effectude dans le but d’identifier les...dimension des a~ro-efs sur les exigences de conception relatives A la resistance A l-cras( , e ,_: l’implantation du code KRASH au Canada pour uniformiser

  9. A Magellanic origin of the DES dwarfs

    NASA Astrophysics Data System (ADS)

    Jethwa, P.; Erkal, D.; Belokurov, V.

    2016-09-01

    We establish the connection between the Magellanic Clouds (MCs) and the dwarf galaxy candidates discovered in the Dark Energy Survey (DES) by building a dynamical model of the MC satellite populations, based on an extensive suite of tailor-made numerical simulations. Our model takes into account the response of the Galaxy to the MCs infall, the dynamical friction experienced by the MCs and the disruption of the MC satellites by their hosts. The simulation suite samples over the uncertainties in the MC's proper motions, the masses of the MW and the Clouds themselves, and allows for flexibility in the intrinsic volume density distribution of the MC satellites. As a result, we can accurately reproduce the DES satellites' observed positions and kinematics. Assuming that Milky Way (MW) dwarfs follow the distribution of sub-haloes in Λ cold dark matter, we further demonstrate that, of 14 observed satellites, the MW halo contributes fewer than 4(8) of these with 68(95) per cent confidence and that 7(12) DES dwarfs have probabilities greater than 0.7(0.5) of belonging to the Large Magellanic Cloud (LMC). Marginalizing over the entire suite, we constrain the number of Magellanic satellites in the range -7 < MV < -1 which exceed the DES surface brightness threshold at ˜70, and the mass of the LMC around 1011 M⊙. The data also strongly support a first-infall scenario for the LMC. Finally, we give predictions for the line-of-sight velocities and the proper motions of the satellites discovered in the vicinity of the LMC.

  10. Scramjet Thermal Management (Tenue thermique des superstatoreacteurs)

    DTIC Science & Technology

    2010-09-01

    combustion). Airbreathing launchers could typically use hydrogen-fuelled DMR. Less energetic fuels like hydrocarbons could also be used at a Mach number ...failing to comply with a collection of information if it does not display a currently valid OMB control number . 1. REPORT DATE SEP 2010 2. REPORT TYPE...N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Scramjet Thermal Management (Tenue thermique des superstatoréacteurs) 5a. CONTRACT NUMBER 5b

  11. Peste des petits ruminants in Arabian wildlife.

    PubMed

    Kinne, J; Kreutzer, R; Kreutzer, M; Wernery, U; Wohlsein, P

    2010-08-01

    Recurrence of peste des petits ruminants (PPR) was diagnosed in the United Arabian Emirates in several wild ruminants confirmed by morphological, immunohistochemical, serological and molecular findings. Phylogenetic analysis revealed that the virus strain belongs to lineage IV, which is different to some previously isolated PPR strains from the Arabian Peninsula. This study shows that wild ruminants may play an important epidemiological role as virus source for domestic small ruminants.

  12. Dermatomyosite et panniculite: place des immunoglobulines

    PubMed Central

    Abdelhafidh, Nadia Ben; Toujeni, Sana; Kefi, Asma; Bousetta, Najeh; Sayhi, Sameh; Gharsallah, Imen; Othmani, Salah

    2016-01-01

    La panniculite est une maladie inflammatoire du tissu adipeux sous-cutané rarement associée à la dermatomyosite. Elle peut survenir avant, après ou en même temps que l'atteinte musculaire. Dans la plupart des cas, l’évolution de la panniculite et des autres atteintes de la dermatomyosite est favorable sous traitement corticoïde et/ou immunosuppresseur. Nous rapportons le cas d'une patiente âgée de 48 ans ayant présenté des lésions de panniculite précédant de 2 mois les signes musculaires. L'atteinte cutanée était résistante au traitement corticoïde associés aux immunosuppresseurs ce qui a nécessité le recours au traitement par Immunoglobulines polyvalentes permettant ainsi une amélioration à la fois de l'atteinte cutanée et musculaire. PMID:27516827

  13. Sonderverfahren des Spritzgießens

    NASA Astrophysics Data System (ADS)

    Michaeli, Walther; Lettowsky, Christoph

    Das Spritzgießen ist neben der Extrusion das wichtigste Verarbeitungsverfahren für Kunststoffe [1]. Das Verfahren hat sich seit seinen Ursprüngen Ende des 19. Jahrhunderts bis heute stetig weiterentwickelt [2]. In neuerer Zeit steigt die Anzahl komplexer Anwendungen, die die gezielte Kombination verschiedener Funktionalitäten in einem Formteil erfordern. Das Standard-Spritzgießen kann diese Anforderungen immer weniger befriedigen. Daher gewinnen die Sonderverfahren des Spritzgießens zunehmend an Bedeutung [3]. Ihre Anzahl beträgt inzwischen über 100. Die Aufgabe des Anwenders ist es, aus der Vielzahl der möglichen Verfahren, ein anforderungsgerechtes auszuwählen, das sowohl unter technischen wie wirtschaftlichen Gesichtspunkten die optimale Lösung darstellt. Dies setzt die ständige Auseinandersetzung mit Entwicklungstendenzen im Bereich der Spritzgießtechnologie voraus. Daher soll im folgenden Abschnitt ein Überblick über die wichtigsten Spritzgieß-Sonderverfahren gegeben werden.

  14. Newtons Universum. Materialien zur Geschichte des Kraftbegriffes.

    NASA Astrophysics Data System (ADS)

    Mit einem Vorwort von E. Seibold und einer Einführung von W. Neuser. This book is a selection of 15 articles published in the journal "Spektrum der Wissenschaft". The original English versions of the papers were first published in "Scientific American". Contents: 1. Impetustheorie und Intuition in der Physik (M. McCloskey). 2. Mittelalterliche Ursprünge der industriellen Revolution (T. S. Reynolds). 3. Leonardo da Vincis Beiträge zur theoretischen Mechanik (V. Foley, W. Soedel). 4. Nikolaus Kopernikus und Tycho Brahe (O. Gingerich). 5. Keplers Entdeckung der ersten beiden Planetengesetze (C. Wilson). 6. Galileis Entdeckung des Fallgesetzes (S. Drake). 7. Galileis Beobachtung des Neptun (S. Drake, C. T. Kowal). 8. Galileo Galilei und der Schatten des Giordano Bruno (L. S. Lerner, E. A. Gosselin). 9. Der Fall Galilei (O. Gingerich). 10. Newtons Apfel und Galileis "Dialog" (S. Drake). 11. Newtons Gravitationsgesetz - aus Formeln wird eine Idee (I. B. Cohen). 12. Christopher Wren: Astronom und Architekt (H. Dorn, R. Mark). 13. Atomismus und Kräfte in der Geschichte (L. Holliday). 14. Ein Elitezirkel vor 200 Jahren: Die Lunar Society von Birmingham (L. Ritchie-Calder). 15. Sadi Carnot: Technik und Theorie der Dampfmaschine (S. S. Wilson).

  15. Combustion of Solid Propellants (La Combustion des Propergols Solides)

    DTIC Science & Technology

    1991-07-01

    on peut s’interroger sur l’adquation des moyens engages ausceptiblea do se manifester naturellement au cours du A Ia complexit6 du probl~me... capteur d’Helmoltz; de pression lorsque Ia fr~quence vanet. Calcul num~rique et mithode expdrimentale donnent des irdsultats en bon accord, c’cst-i... naturellement , avec des niveaux stabilis~s moddr~s. mod~le de combustion (r~f. 30) et des limites de L’opinion est r~pandue que la segmentation peut l’approche

  16. Inhomogeneites dans le Vent des Etoiles Wolf-Rayet

    NASA Astrophysics Data System (ADS)

    Robert, Carmelle

    1992-01-01

    Des mesures spectroscopiques effectuees avec un haut rapport signal sur bruit et une bonne resolution ont demontre l'existence de regions perturbees en mouvement dans le vent d'etoiles Wolf-Rayet (WR). L'echantillon d'objets etudies ici comprend 9 etoiles WR couvrant differents sous-types WN et WC. De nombreuses petites structures variables superposees au profil des raies d'emission formees dans le vent stellaire signalent la presence des perturbations. L'etude des variations globales des raies et l'examen des micro-structures individuelles ont permis de decrire plusieurs caracteristiques des perturbations. Entre autres, on observe des correlations significatives entre le niveau de variabilite des raies et certains parametres des etoiles qui confirment que le phenomene de variabilite est intrinseque au vent stellaire. En comparant les changements des vitesses radiales et des largeurs equivalentes des differentes raies d'une meme etoile, on conclut que les regions perturbees ont une etendue finie par rapport a l'enveloppe des etoiles. On peut facilement suivre les structures individuelles sur une periode de temps couvrant ~eq8 heures (et peut etre meme 24 heures) avant qu'elles ne disparaissent. Durant ce temps les structures se deplacent en s'eloignant du centre de la raie. A partir des differents comportements notes lors de l'analyse des variations globales et lors de l'examen des structures individuelles, on propose de representer les perturbations par un modele d'inhomogeneites discretes en expansion dans le vent. On suppose simplement que les inhomogeneites emettent comme le vent global (et absorbent aussi si le vent global montre un profil P Cyg). La superposition du graphique de l'acceleration radiale moyenne des inhomogeneites de WR140 en fonction de leur vitesse radiale et du modele theorique d'inhomogeneites qui suivent la loi generale de vitesse donne un taux d'acceleration lent, avec beta >= 3 pour les inhomogeneites de cette etoile. On obtient, entre

  17. Reconnaissance des Formes a L'aide du Filtre de Phase D'harmoniques Circulaires

    NASA Astrophysics Data System (ADS)

    Leclerc, Luc

    Cette these porte sur l'etude d'une nouvelle generation de filtres fabriques a partir de la phase du filtre d'harmoniques circulaires (FHC). Il s'agit du FHC de phase (FHCP), du FHC de phase binaire (FHCPB) et du FHC binaire (FHCB) qui, tout en etant invariants par rapport a la position et a l'orientation des cibles, offrent une meilleure capacite de discrimination que le FHC. Nous presentons egalement le FHC de covariance (FHCC) et ses derives de phase, lesquels permettent d'accroi tre davantage la capacite de discrimination du FHC dans les cas ou les objets composants la scene sont tres semblables. La performance de chacun des filtres est evaluee au moyen de simulations sur ordinateur avant d'etre mesuree sur un correlateur optique. Le FHC, FHCP, FHCC et FHCCP sont encodes dans un hologramme genere par ordinateur tandis que les filtres binaires sont affiches sur un televiseur a cristaux liquides. Enfin, nous termions ce manuscrit en presentant le FHCB multiplexe qui permet de correler, en une seule operation, un objet et plusieurs FHC de differents ordres.

  18. Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

    PubMed Central

    Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

    2014-01-01

    RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la

  19. Annual Program Management Report (1990), Des Moines Recreational River and Greenbelt, Des Moines River, Iowa

    DTIC Science & Technology

    1990-12-01

    study are listed below: STUDY MANAGEMENT C111 Jim MIll I SITE PLANNING George Gitter, AICP ECONOMIC AND SOCIAL ANALYSIS Patricia Risser ENVIRONMENTAL...Trail (Raccoon River Segment), Des Moines - The project involves the construction of approximately 42,500 feet of paved multi-purpose trail in the...Federd Fee kwe Sc Am 1000 02000 ~]Lod Area -~ aroraed SCALE FEET Des Moies Recreaond Rvf And Greenbdt U.S. ARMY VNGDIKE DITrWC - ROC BLAND -A MOCK SA’rL0A

  20. Les effets du travail en equipe dans l'apprentissage par projets sur la motivation des etudiantes et des etudiants en formation des ingenieurs

    NASA Astrophysics Data System (ADS)

    Fernandez, Nicolas

    Les representants des secteurs industriels et les, milieux professionnels en Amerique du Nord reprochaient aux universites de former des ingenieurs avec peu d'experience pratique en resolution de problemes et en conception. Quelques programmes de genie ont alors mis en place le travail en equipe dans l'apprentissage par projets. Beaucoup d'ecrits font valoir les benefices de l'apprentissage par projets sur la motivation des etudiants. Or, ces benefices commencent a peine a faire l'objet de recherches visant a produire des donnees probantes a ce sujet. Les travaux sur la motivation en contexte d'apprentissage et les modeles theoriques developpes sont issus d'environnements d'apprentissage marques par l'enseignement magistral. Le modele de la valeur attendue de la tache (Eccles et Wigfield, 1995; Neuville, 2004) et le modele du systeme-groupe (St-Arnaud, 2008) ont ete retenus pour mesurer les effets du travail en equipe dans l'apprentissage par projets sur la motivation. La recherche visait aussi a approfondir et a nuancer la comprehension de la motivation des etudiants universitaires apprenant en contexte innovant. Les sujets constituent des etudiants (n=100) travaillant sur des projets d'integration au cours des trois sessions initiales du programme de genie mecanique d'une universite canadienne. L'analyse de regression multiple revele que les construits de la motivation expliquent un tiers de la variance de l'engagement academique dans la realisation du projet d'integration. Les perceptions de l' "expectancy", de la valeur intrinseque et utilitaire sont les determinants principaux de l'engagement des etudiants. L'analyse de variance multivariee a mesures repetees indique que la motivation des etudiants pour le travail sur les projets d'integration a augmente au cours des trois sessions initiales du parcours de formation. Finalement, malgre l'absence d'interaction significative entre les variables de motivation et de l'equipe, les reponses des sujets indiquent une

  1. La physique des bulles de champagne Une première approche des processus physico-chimiques liés à l'effervescence des vins de Champagne

    NASA Astrophysics Data System (ADS)

    Liger-Belair, G.

    2002-07-01

    bubbles collapsing at a free surface. But, to the best of our knowledge, and surprising as it may seem, no results concerning the collateral effects on adjoining bubbles of bubbles collapsing in a bubble monolayer have been reported up to now. Actually, effervescence in a glass of champagne ideally lends to a preliminary work with bubbles collapsing in a bubble monolayer. For a few seconds after pouring, the free surface is completely covered with a monolayer composed of quite monodisperse millimetric bubbles collapsing close to each others. We took high-speed photographs of the situation which immediately follows the rupture of a bubble cap in a bubble monolayer. Adjoining bubbles were found to be literally sucked and strongly stretched toward the lowest part of the cavity left by the bursting bubble, leading to unexpected and short-lived flower-shaped structures. Stresses in distorted bubbles (petals of the flower-shaped structure) were evaluated and found to be, at least, one order of magnitude higher than stresses numerically calculated in the boundary layer around an isolated single millimetric collapsing bubble. This is a brand-new and slightly counter-intuitive result. While absorbing the energy released during collapse, as an air-bag would do, adjoining bubble caps store this energy into their thin liquid film, leading finally to stresses much higher than those observed in the boundary layer around single millimetric collapsing bubbles. Further investigation should be conducted now, and especially numerically, in order to better understand the relative influence of each pertinent parameters (bubble size, liquid density and viscosity, effect of surfactant...) on bubble deformation. L'objectif général de cet ouvrage consacré à l'étude des processus physico- chimiques de l'effervescence des vins de Champagne était de décortiquer les différentes étapes de la vie d'une bulle de champagne en conditions réelles de consommation, dans une flûte. Nous r

  2. Proprietes Adiabatiques des Naines Blanches Pulsantes de Type ZZ Ceti

    NASA Astrophysics Data System (ADS)

    Brassard, Pierre

    1992-01-01

    Cette these a pour but d'etudier les proprietes des oscillation non-radiales des etoiles ZZ Ceti, appelees aussi etoiles DA variables, dans le contexte de la theorie adiabatique des petites oscillations. Ces oscillations sont observables, pour ce type d'etoiles, sous forme de variations periodiques de la luminosite. A partir d'une analyse de modeles stellaires, analyse qui consiste principalement a calculer et a interpreter les periodes d'oscillations des modeles, nous voulons mieux connai tre les proprietes physiques fondamentales des ZZ Ceti. Nous developpons tout d'abord divers outils pour entreprendre cette etude. Apres avoir presente le formalisme mathematique de base decrivant les oscillations non-radiales d'une etoile, nous discutons des difficultes pouvant etre rencontrees dans le calcul de la frequence de Brunt-Vaisala, une quantite fondamentale pour le calcul des periodes d'oscillations. Par la suite, nous developpons un modele theorique simple permettant d'analyser et d'interpreter la structure des periodes calculees (ou observees) en termes des proprietes de structure de l'etoile. Nous presentons aussi les outils numeriques tout a fait originaux utilises pour calculer nos periodes a partir de modeles stellaires. Finalement, nous presentons les resultats d'ensemble de l'analyse de nos modeles, et discutons de l'interpretation des observations de periodes et du taux de variation de ces periodes en termes de structure de l'etoile et de composition du noyau de l'etoile, respectivement. Ces resultats representent l'etude la plus complete a ce jour de la seismologie des naines blanches.

  3. Etude des melanges co-continus d'acide polylactique et d'amidon thermoplastique (PLA/TPS)

    NASA Astrophysics Data System (ADS)

    Chavez Garcia, Maria Graciela

    Les melanges co-continus sont des melanges polymeriques ou chaque composant se trouve dans une phase continue. Pour cette raison, les caracteristiques de chacun des composants se combinent et il en resulte un materiau avec une morphologie et des proprietes particulieres. L'acide polylactique (PLA) et l'amidon thermoplastique (TPS) sont des biopolymeres qui proviennent de ressources renouvelables et qui sont biodegradables. Dans ce projet, differents melanges de PLA et TPS a une haute concentration de TPS ont ete prepares dans une extrudeuse bi-vis afin de generer des structures co-continues. Grace a la technique de lixiviation selective, le TPS est enleve pour creer une structure poreuse de PLA qui a pu etre analysee au moyen de la microtomographie R-X et de la microscopie electronique a balayage MEB. L'analyse des images 2D et 3D confirme la presence de la structure co-continue dans les melanges dont la concentration en TPS. se situe entre 66% et 80%. L'effet de deux plastifiants, le glycerol seul et le melange de glycerol et de sorbitol, dans la formulation de TPS est etudie dans ce travail. De plus, nous avons evalue l'effet du PLA greffe a l'anhydride maleique (PLAg) en tant que compatibilisant. On a trouve que la phase de TPS obtenue avec le glycerol est plus grande. L'effet de recuit sur la taille de phases est aussi analyse. Grace aux memes techniques d'analyse, on a etudie l'effet du procede de moulage par injection sur la morphologie. On a constate que les pieces injectees presentent une microstructure heterogene et differente entre la surface et le centre de la piece. Pres de la surface, une peau plus riche en PLA est presente et les phases de TPS y sont allongees sous forme de lamelles. Plus au centre de la piece, une morphologie plus cellulaire est observee pour chaque phase continue. L'effet des formulations sur les proprietes mecaniques a aussi ete etudie. Les pieces injectees dont la concentration de TPS est plus grande presentent une moindre

  4. A novel silica alumina-based backfill material composed of coal refuse and fly ash.

    PubMed

    Yao, Yuan; Sun, Henghu

    2012-04-30

    In this paper, a systematic study was conducted to investigate a novel silica alumina-based backfill material composed of coal refuse and fly ash. The coal refuse and fly ash had different properties under various thermal activation temperatures (20 °C, 150 °C, 350 °C, 550 °C, 750 °C and 950 °C). It is known that a thermal activation temperature ranging from 20 °C to 950 °C significantly increases the flowability and pozzolanic properties of the coal refuse; however, the flowability of fly ash decreases when the activation temperature is higher than 550 °C because of a severe agglomeration phenomenon on its surface. An optimal design for this backfill material was determined to include an activated portion composed of 5% coal refuse at 750 °C and 15% fly ash at 20 °C. This combination yields the best performance with excellent flowability, a high compressive strength and a low bleeding rate. The microanalysis results corresponded well with the performance tests at different activation conditions. In the coal refuse, kaolinite peaks began to decrease because of their transformation into metakaolin at 550 °C. Chlorite peaks disappeared at 750 °C. Muscovite peaks decreased at 750 °C and disappeared at 950 °C. During this process, muscovite 2M(1) gradually dehydroxylated to muscovite HT. Furthermore, this paper examined the environmental acceptance and economic feasibility of this technology and found that this silica alumina-based backfill material composed of coal refuse and fly ash not only meets EPA requirements but also has several advantages in industry feasibility when compared with hydraulic backfill, rock backfill and paste backfill.

  5. International Workshop on Beam Injection Assessment of Defects in Semiconductors Held in Meudon-Bellevue (France) on 18-20 July 1988

    DTIC Science & Technology

    1989-07-20

    for high resistivity material. On the other hand, a contrast mechanism is necessary to interpret quantitatively the LBIC signal for a specific defect...cathodoluminescence effect of hydrogen and deformation A. Djemel, J. Castaing Laboratoire de Physique des Materiaux J. Chevallier Laboratoire de Physique des Solides

  6. High Temperature Monotonic and Cyclic Deformation in a Directionally Solidified Nickel-Base Superalloy.

    DTIC Science & Technology

    1986-05-01

    34Metallurgical Aspects of High Temperature Fatigue." Fatigue des Materiaux et des Structures. C. Bathias and J. P. Bailon, editors (1978). 5. S. D. Antolovich...hinge. A spring steel loop was wound around the top extensometer rod for attachment of the extensometer suspension cord, and two more spring steel

  7. Giant molecules composed of polar molecules and atoms in mixed dimensions

    NASA Astrophysics Data System (ADS)

    Qi, Ran; Tan, Shina

    2014-05-01

    Two or three polar molecules, confined to one or two dimensions, can form stable bound states with a single atom living in three dimensions, if the molecule and the atom can interact resonantly such that their mixed dimensional scattering length is large. We call these bound states ``giant molecules'' since it's a molecule composed of smaller molecules and atoms. We study their properties using techniques including exact numerical solution, exact qunatum diffusion Monte Carlo (QMC), Born-Oppenheimer approximation (BOA), and semiclassical approximation. These bound states have a hierarchical structure reminiscent of the celestial systems.

  8. First Description of Discrete Stars Composing the Milky Way in Thomas Watson's Hekatompathia (1582)

    NASA Astrophysics Data System (ADS)

    Altschuler, E. L.; Jansen, W.

    2003-12-01

    We note the first description of the Milky Way as being composed of a large number of discrete stars in Sonnet 31 of Thomas Watson's (d 1592) Hekatompathia (1582). After prefatory material invoking classical sources and making clear he is discussing the Milky Way, Watson's poem then starts: Who can recount the vertues of my deare, Or say how farre her fame hath taken flight, That can not tell how many starres appeare In part of heav'n, which Galaxia hight, Or number all the moates in Phebus rayes, Or golden sandes, wheron Pactolus playes? We discuss the scientific, literary and historical significance of this finding.

  9. Magnetically tunable double-negative material composed of ferrite-dielectric and metallic mesh

    NASA Astrophysics Data System (ADS)

    He, Guanghua; Wu, Rui-xin; Poo, Yin; Chen, Ping

    2010-05-01

    We designed and studied a magnetic tunable metamaterial composed of ferrite-dielectric and metallic mesh. The retrieved electromagnetic parameters and the transmission characteristic showed the composite has a double-negative regime in magnetized state. Moreover, this regime is tunable in external magnetic fields. The composite has a lower loss with minimum about -0.3 dB/mm. The simulations of the wave propagation on the interface of the composite clearly display a negative refraction. The negative indexes calculated from Snell's law are in good agreement with the indexes retrieved from S parameters, quantitatively confirms the negative index of the composite.

  10. Optimization of global model composed of radial basis functions using the term-ranking approach

    SciTech Connect

    Cai, Peng; Tao, Chao Liu, Xiao-Jun

    2014-03-15

    A term-ranking method is put forward to optimize the global model composed of radial basis functions to improve the predictability of the model. The effectiveness of the proposed method is examined by numerical simulation and experimental data. Numerical simulations indicate that this method can significantly lengthen the prediction time and decrease the Bayesian information criterion of the model. The application to real voice signal shows that the optimized global model can capture more predictable component in chaos-like voice data and simultaneously reduce the predictable component (periodic pitch) in the residual signal.

  11. Efficacy of a self-etching dentin primer composed of TEGMA and phenyl-P.

    PubMed

    Yoshimoto, Shinichiro; Itoh, Kazuo; Manabe, Atsufumi; Inoue, Mitsuko; Hisamitsu, Hisashi; Sasa, Ryuuji

    2004-01-01

    The purpose of the present study was to evaluate the efficacy of an experimental self-etching dentin primer composed of TEGMA and phenyl-P using primary and young permanent teeth. The efficacy of the self-etching dentin primer was evaluated by measuring the wall-to-wall polymerization contraction gap width and the shear bond strength to the flat dentin surface. The contraction gap formation was prevented completely in the specimens primed with the 35 vol% TEGMA and 20% phenyl-P for 30 sec.

  12. Tunable absorption in heterostructures composed of a highly absorptive metallic film and Fibonacci fractal photonic crystals

    NASA Astrophysics Data System (ADS)

    Qiao, Wei; Sun, Jie; Du, Gui-Qiang

    2016-03-01

    We have theoretically investigated the anomalous optical properties of heterostructures composed of a highly absorptive metal film and a truncated Fibonacci fractal photonic crystal. It is found that one or multiple highly reflected peaks, even enhanced transmission narrowband, can be realized in the near-complete absorption broadband, where the photonic crystals are selected with various Fibonacci sequences or a given sequence as the basic unit. These properties are significant to design important reflection or transmission optical devices in the visible and near-infrared ranges.

  13. Hydrogen consentration meter utilizing a diffusion tube composed of 2 1/4 C r

    DOEpatents

    Roy, Prodyot; Sandusky, David W.; Hartle, Robert T.

    1979-01-01

    A diffusion tube hydrogen meter for improving the sensitivity and response time for the measurement of hydrogen in liquid sodium. The improved hydrogen meter has a composite membrane composed of pure nickel sleeve fitted, for example, over a 2 1/4 Cr-1 Mo steel or niobium diffusion tube. Since the hydrogen permeation rate through 2 1/4 Cr-1 Mo steels is a factor of four higher than pure nickel, and the permeation rate of hydrogen through niobium is two orders of magnitude greater than the 2 1/4 Cr-1 Mo steel, this results in a decrease in response time and an increase in the sensitivity.

  14. La modelisation mathematique dans l'enseignement de la chimie des gaz a des eleves de la cinquieme annee du secondaire

    NASA Astrophysics Data System (ADS)

    Gauthier, Diane

    Les problemes d'enseignement de la chimie des gaz parfaits sont donc importants. Si plusieurs etudes ont ete realisees dans le but d'identifier et d'interpreter ces problemes, aucune recherche, a notre connaissance, n'a ete realisee sur l'enseignement des lois sur les gaz parfaits. Notre recherche sur l'enseignement est donc pionniere. Elle a pour objectif general de construire et d'analyser une sequence d'enseignement de la chimie des gaz comportant diverses situations de modelisation mathematique des conduites des gaz. Les principaux objectifs specifiques sont les suivants: (1) identifier et caracteriser les situations qui provoquent une evolution des conceptions naives des eleves, evolution vers des connaissances plus adequate sur les gaz; (2) identifier et caractEriser les situations qui provoquent une evolution des connaissances mathematiques des eleves leur permettant d'interpreter convenablement les resultats des experiences, d'eprouver leurs conceptions, de donner un sens aux notions et aux relations impliquees dans les lois des gaz parfaits, lois de Boyle-Mariotte et Gay-Lussac. Une sequence d'enseignement comportant huit situations est d'eleves de secondaire V. La construction de ces situations est orientee par les recherches sur les conceptions naives des eleves, par les etudes sur l'evolution historique des conceptions sur les gaz et des pratiques scientifiques, ainsi que par les etudes theoriques et empiriques realisees en didactique des sciences et des mathematiques. La methodologie de l'ingenierie didactique (Artigue, 1998) qui constitue une application de la theorie des situations didactiques (Brousseau, 1986) est utilisee dans la construction et l'analyse des situations d'enseignement. Une analyse a priori de chacune des situations d'enseignement est effectuee; elle a pour but dexpliquer les choix des taches qui font partie des situations et de preciser la gestion didactique des situations. Diverses situations d'enseignement de la chimie ont ainsi

  15. Etude des chaines de spins par les methodes de la theorie quantique des champs

    NASA Astrophysics Data System (ADS)

    Allen, Dave

    Notre etude porte sur la chaine de spins en zigzag avec dimerisation dans le cas des spins 1/2 et 1. L'echelle de spin ordinaire et la chaine en zigzag simple en sont des cas particuliers. Dans la limite continue, ces systemes sont decrits par des modeles Wess-Zumino-Witten couples. Afin de pouvoir calculer les fonctions de correlation, nous exposons differentes equivalences quantiques permettant de simplifier les calculs. Dans le cas de chaines de spin 1/2, nous demontrons l'equivalence avec un modele de type Gross-Neveu, en fonction de fermions de Majorana; ces fermions decrivent alors les excitations elementaires du systeme. Nous exposons une vision classique de ces excitations afin de voir les mecanismes de confinement des spinons. Dans le cas de chaines de spin 1, l'etude est plus complexe. Nous pouvons decrire le systeme a l'aide de modeles sine-Gordon perturbes par de nombreuses interactions. En se limitant aux plus importantes, nous pouvons expliquer le comportement du gap en fonction du couplage interchaine observe numeriquement.

  16. 75 FR 63714 - Drawbridge Operation Regulation; Des Allemands Bayou, LA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ... Burlington Northern Santa Fe Railway swing bridge across Des Allemands Bayou, mile 14.0, in St. Charles and... INFORMATION: The Burlington Northern Santa Fe Railway swing span drawbridge across Bayou Des Allemands, mile... tows, fishing vessels and recreational craft. The Burlington Northern Santa Fe Railway requested...

  17. Vers des boites quantiques a base de graphene

    NASA Astrophysics Data System (ADS)

    Branchaud, Simon

    Le graphene est un materiau a base de carbone qui est etudie largement depuis 2004. De tres nombreux articles ont ete publies tant sur les proprietes electroniques, qu'optiques ou mecaniques de ce materiel. Cet ouvrage porte sur l'etude des fluctuations de conductance dans le graphene, et sur la fabrication et la caracterisation de nanostructures gravees dans des feuilles de ce cristal 2D. Des mesures de magnetoresistance a basse temperature ont ete faites pres du point de neutralite de charge (PNC) ainsi qu'a haute densite electronique. On trouve deux origines aux fluctuations de conductance pres du PNC, soit des oscillations mesoscopiques provenant de l'interference quantique, et des fluctuations dites Hall quantique apparaissant a plus haut champ (>0.5T), semblant suivre les facteurs de remplissage associes aux monocouches de graphene. Ces dernieres fluctuations sont attribuees a la charge d'etats localises, et revelent un precurseur a l'effet Hall quantique, qui lui, ne se manifeste pas avant 2T. On arrive a extraire les parametres caracterisant l'echantillon a partir de ces donnees. A la fin de cet ouvrage, on effectue des mesures de transport dans des constrictions et ilots de graphene, ou des boites quantiques sont formees. A partir de ces mesures, on extrait les parametres importants de ces boites quantiques, comme leur taille et leur energie de charge.

  18. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  19. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  20. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  1. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  2. 33 CFR 117.439 - Des Allemands Bayou.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Des Allemands Bayou. 117.439 Section 117.439 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.439 Des Allemands Bayou. (a) The...

  3. Conception et realisation d'un recepteur compose de reseau d'antennes Yagi multicouches verticales et de composants en ondes millimetriques

    NASA Astrophysics Data System (ADS)

    Kramer, Olivier

    Millimeter wave applications such as high-speed wireless connections require modular, compact-size, low-cost and high-performance systems. In order to realize a complete receiver satisfying those requirements, compact stacked multilayered designs are presented in this thesis. First, high-gain compact stacked multilayered Yagi designs are proposed and demonstrated at 5.8 GHz. The structure makes use for the first time of vertically stacked Yagi-like parasitic director elements that allow easily obtaining a simulated gain of 12 dBi. Two different antenna configurations are presented, one based on dipole geometry for single polarization, and the other on a circular patch to achieve dual polarization. Measured results of the fabricated antenna prototypes are in good agreement with simulated results. Second, based on the above-demonstrated principle, the antenna is redesigned and adapted for 60 GHz applications, and a novel design showing for the first time an array of Yagi elements in millimeter wave stacked structure is presented. An analysis is performed to define the structure limits. The measured element attains 11 dBi of gain. The proposed 4x4 array has a size of 50x50x60 mm3, and reaches a measured gain of 18 dBi over 7% of bandwidth. An alternative configuration of the array using angled Yagi antenna elements allows for a significant improvement of the side lobe level without a visible impact on the gain. The proposed antennas present excellent candidates for integrated low-cost millimeter-wave systems that require small footprint. Third, a novel dual layered six-port front-end circuit using the Substrate Integrated Waveguide (SIW) technology is presented and demonstrated. The six-port architecture makes use of multilayer couplers, providing a wide coupling area through two slots; a new broadband SIW phase shifter composed of two H-plane stub lines and one reference line; and two SIW power dividers. Simulation and measurement results show that the proposed six

  4. In vitro evaluation of tissue adhesives composed of hydrophobically modified gelatins and disuccinimidyl tartrate

    NASA Astrophysics Data System (ADS)

    Matsuda, Miyuki; Taguchi, Tetsushi

    2012-12-01

    The effect of the hydrophobic group content in gelatin on the bonding strength of novel tissue-penetrating tissue adhesives was evaluated. The hydrophobic groups introduced into gelatin were the saturated hexanoyl, palmitoyl, and stearoyl groups, and the unsaturated oleoyl group. A collagen casing was employed as an adherend to model soft tissue for the in vitro determination of bonding strength of tissue adhesives composed of various hydrophobically modified gelatins and disuccinimidyl tartrate. The adhesive composed of stearoyl-modified gelatin (7.4% stearoyl; 10Ste) and disuccinimidyl tartrate showed the highest bonding strength. The bonding strength of the adhesives decreased as the degree of substitution of the hydrophobic groups increased. Cell culture experiments demonstrated that fluorescein isothiocyanate-labeled 10Ste was integrated onto the surface of smooth muscle cells and showed no cytotoxicity. These results suggest that 10Ste interacted with the hydrophobic domains of collagen casings, such as hydrophobic amino acid residues and cell membranes. Therefore, 10Ste-disuccinimidyl tartrate is a promising adhesive for use in aortic dissection.

  5. Direct fabrication of hybrid nanofibres composed of SiO2-PMMA nanospheres via electrospinning.

    PubMed

    Zhang, Ran; Shang, Tinghua; Yang, Guang; Jia, Xiaolong; Cai, Qing; Yang, Xiaoping

    2016-08-01

    The direct fabrication of hybrid nanofibres composed of poly(methyl methacrylate)-grafted SiO2 (SiO2-PMMA) nanospheres via electrospinning was investigated in detail. SiO2-PMMA nanospheres were successfully prepared, with the SiO2 nanospheres synthesized via the Stober method, followed by in situ surface-initiated atom transfer radical polymerization of methyl methacrylate (MMA). Electrospinning was carried out with N,N-dimethylformamide (DMF) as the solvent to disperse SiO2-PMMA nanospheres. The size of the SiO2 core, the molecular weight of the PMMA shell and the concentration of the SiO2-PMMA/DMF solution all had substantial effects on the morphology and structure of electrospun nanofibres composed of SiO2-PMMA nanospheres. When these determining factors were well-tailored, it was found that one-dimensional necklace-like nanofibres were obtained, with SiO2-PMMA nanospheres aligned one by one along the fibre. The successful fabrication of nanofibres by directly electrospinning the SiO2-PMMA/DMF solution verified that polymer-grafted particles possess polymer-like characteristics, which endowed them with the ability to be processed into desirable shapes and structures.

  6. Menstrual cycle phase alters women's sexual preferences for composers of more complex music.

    PubMed

    Charlton, Benjamin D

    2014-06-07

    Over 140 years ago Charles Darwin first argued that birdsong and human music, having no clear survival benefit, were obvious candidates for sexual selection. Whereas the first contention is now universally accepted, his theory that music is a product of sexual selection through mate choice has largely been neglected. Here, I provide the first, to my knowledge, empirical support for the sexual selection hypothesis of music evolution by showing that women have sexual preferences during peak conception times for men that are able to create more complex music. Two-alternative forced-choice experiments revealed that woman only preferred composers of more complex music as short-term sexual partners when conception risk was highest. No preferences were displayed when women chose which composer they would prefer as a long-term partner in a committed relationship, and control experiments failed to reveal an effect of conception risk on women's preferences for visual artists. These results suggest that women may acquire genetic benefits for offspring by selecting musicians able to create more complex music as sexual partners, and provide compelling support for Darwin's assertion 'that musical notes and rhythm were first acquired by the male or female progenitors of mankind for the sake of charming the opposite sex'.

  7. Nonenzymatic glucose sensor based on CuO microfibers composed of CuO nanoparticles.

    PubMed

    Cao, Fei; Gong, Jian

    2012-04-20

    Fluorine tin oxide (FTO) electrode modified by copper oxide microfibers (CuO-MFs) composed of numerous interconnected CuO nanoparticles (CuO-NPs) for nonenzymatic glucose sensor was prepared by electrospinning precursor containing high percentage content of copper nitrate with subsequent calcination. The results of scanning electron microscope (SEM) showed the size of CuO particles composing CuO-MFs depended on the percentage content of copper nitrate in precursor solution. With increasing the percentage content of copper nitrate, the interconnected CuO-NPs would gradually replace the large-size CuO particles to accumulate the CuO-MFs, which have the potential to provide larger surface area and more reaction sites for electrocatalytic activity toward glucose. As a glucose sensor, the CuO-MFs modified FTO electrode prepared by 40 wt.% of copper nitrate exhibited a high sensitivity of 2321 μA mM(-1) cm(-2) with a low detection limit of 2.2 nM (signal/noise ratio (S/N)=3). Additionally, the application of the CuO-MFs modified FTO electrode as a glucose sensor for biological samples was demonstrated with satisfactory results.

  8. PbO networks composed of single crystalline nanosheets synthesized by a facile chemical precipitation method

    SciTech Connect

    Samberg, Joshua P.; Kajbafvala, Amir; Koolivand, Amir

    2014-03-01

    Graphical abstract: - Highlights: • Synthesis of PbO networks through a simple chemical precipitation route. • The synthesis method is rapid and low-cost. • Each network is composed of single crystalline PbO nanosheets. • A possible growth mechanism is proposed for synthesized PbO networks. - Abstract: For the field of energy storage, nanostructured lead oxide (PbO) shows immense potential for increased specific energy and deep discharge for lead acid battery technologies. In this work, PbO networks composed of single crystalline nanosheets were synthesized utilizing a simple, low cost and rapid chemical precipitation method. The PbO networks were prepared in a single reaction vessel from starting reagents of lead acetate dehydrate, ammonium hydroxide and deionized water. Lead acetate dehydrate was chosen as a reagent, as opposed to lead nitrate, to eliminate the possibility of nitrate contamination of the final product. X-ray diffraction (XRD) analysis, high resolution scanning electron microscopy (HRSEM) and high resolution transmission electron microscopy (HRTEM) analysis were used to characterize the synthesized PbO networks. The reproducible method described herein synthesized pure β-PbO (massicot) powders, with no byproducts. A possible formation mechanism for these PbO networks is proposed. The growth is found to proceed predominately in the 〈1 1 1〉 and 〈2 0 0〉 directions while being limited in the 〈0 1 1〉 direction.

  9. Menstrual cycle phase alters women's sexual preferences for composers of more complex music

    PubMed Central

    Charlton, Benjamin D.

    2014-01-01

    Over 140 years ago Charles Darwin first argued that birdsong and human music, having no clear survival benefit, were obvious candidates for sexual selection. Whereas the first contention is now universally accepted, his theory that music is a product of sexual selection through mate choice has largely been neglected. Here, I provide the first, to my knowledge, empirical support for the sexual selection hypothesis of music evolution by showing that women have sexual preferences during peak conception times for men that are able to create more complex music. Two-alternative forced-choice experiments revealed that woman only preferred composers of more complex music as short-term sexual partners when conception risk was highest. No preferences were displayed when women chose which composer they would prefer as a long-term partner in a committed relationship, and control experiments failed to reveal an effect of conception risk on women's preferences for visual artists. These results suggest that women may acquire genetic benefits for offspring by selecting musicians able to create more complex music as sexual partners, and provide compelling support for Darwin's assertion ‘that musical notes and rhythm were first acquired by the male or female progenitors of mankind for the sake of charming the opposite sex’. PMID:24759864

  10. A thermo- and pH-sensitive hydrogel composed of quaternized chitosan/glycerophosphate.

    PubMed

    Wu, Jie; Su, Zhi-Guo; Ma, Guang-Hui

    2006-06-06

    The quaternized chitosan was synthesized by the reaction of chitosan and glycidyltrimethylammonium chloride (GTMAC) and named as N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC). A novel hydrogel system composed of HTCC/glycerophosphate (HTCC/GP) with thermo- and pH-sensitivity was synthesized and used as an intelligent drug carrier. The formulation was solution below or at room temperature, which allowed it injectable and to incorporate living cells, proteins, enzymes or other therapeutic drugs easily. Once the surrounding temperature was up to 37 degrees C, the system was transformed to a non-flowing hydrogel, and the formed hydrogel can release the trapped drug as a function of pH values. The swelling behavior of the system and the release profiles of doxorubicin hydrochloride (DX) as a model drug at different pH values were investigated. At acidic condition the hydrogel dissolved and released drug quickly, while it absorbed water and released drug slowly at neutral or basic conditions. Hydrogel composed of chitosan hydrochloride and glycerophosphate (CS/GP) was also prepared to compare with HTCC/GP hydrogel. The HTCC/GP hydrogel in this study was transparent which made it suitable for some specific uses such as ocular drug formulation.

  11. Lipid flip-flop in binary membranes composed of phosphatidylserine and phosphatidylcholine.

    PubMed

    Brown, Krystal L; Conboy, John C

    2013-12-05

    The kinetics and thermodynamics of lipid flip-flop in bilayers composed of 1,2-dipalmitoyl-sn-glycero-3-phospho-L-serine (DPPS) and 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) were studied using sum-frequency vibrational spectroscopy. The kinetics of DSPC and DPPS flip-flop were examined as a function of temperature and bilayer composition. The rate of DSPC flip-flop did not exhibit any significant dependence on bilayer composition while the rate of DPPS flip-flop was inversely dependent on the mole fraction of DPPS. The transition-state thermodynamics for DSPC and DPPS lipids in these mixed bilayers were determined in order to identify the energetic impact of the phosphatidylserine headgroup on lipid flip-flop. The thermodynamics for the DSPC component remained statistically identical to bilayers composed entirely of DSPC. The activation energy for the DPPS component showed a linear correlation with the mole fraction of DPPS for all bilayer compositions. The enthalpy and entropy for DPPS flip-flop did not increase linearly with the fraction of DPPS but did directly correlate with the molecular area. The DPPS component also exhibited enthalpy-entropy compensation which suggests that lipid hydration may play a significant role in membrane dynamics.

  12. Formation of clusters composed of C60 molecules via self-assembly in critical fluids

    NASA Astrophysics Data System (ADS)

    Fukuda, Takahiro; Ishii, Koji; Kurosu, Shunji; Whitby, Raymond; Maekawa, Toru

    2007-04-01

    Fullerenes are promising candidates for intelligent, functional nanomaterials because of their unique mechanical, electronic and chemical properties. However, it is necessary to invent some efficient but relatively simple methods of producing structures composed of fullerenes for the development of nanomechatronic, nanoelectronic and biochemical devices and sensors. In this paper, we show that various structures such as straight fibres, networks formed by fibres, wide sheets and helical structures, which are composed of C60 molecules, are created by placing C60-crystals in critical ethane, carbon dioxide and xenon even though C60 molecules do not dissolve or disperse in the above fluids. It is supposed, judging by the intermolecular potentials between C60 and C60, between C60 and ethane, and between ethane and ethane, that C60-clusters grow with the assistance of solvent molecules, which are trapped between C60 molecules under critical conditions. This room-temperature self-assembly cluster growth process in critical fluids may open up a new methodology of forming structures built up with fullerenes without the need for any ultra-fine processing technologies.

  13. A new nanosensor composed of laminated samarium borate and immobilized laccase for phenol determination

    NASA Astrophysics Data System (ADS)

    Hu, Ping; Zhou, Xinlin; Wu, Qingsheng

    2014-02-01

    A new nanosensor composed of laminated samarium borate and immobilized laccase was developed for phenol determination. The laminated samarium borate was synthesized by a mild solid-state-hydrothermal (S-S-H) method without any surfactant or Template. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used to characterize the samples. The morphology of the as-prepared materials was characterized by SEM, which shows that laminated samarium borate are uniform nanosheets with a layer-by-layer self-assembled single-crystal structure. These laminated samarium borate have typical diameters of 3 ~ 5 μm and the thickness of each layer is in the range of 10 ~ 80 nm. And then, these SmBO3 multilayers were used to immobilize the laccase. The proposed nanosensor composed of laminated samarium borate and immobilized laccase was successfully developed for phenol determination. Cyclic voltammetry were used to study the nanosensor. The proposed nanosensor displayed high sensitivity toward phenolic compounds. The linearity of the nanosensor for the detection of hydroquinone was obtained from 1 to 50 μM with a detection limit of 3 × 10-7 M (based on the S/N = 3).

  14. Etude du processus de changement vecu par des familles ayant decide d'adopter volontairement des comportements d'attenuation des changements climatiques

    NASA Astrophysics Data System (ADS)

    Leger, Michel T.

    Les activites humaines energivores telles l'utilisation intensive de l'automobile, la surconsommation de biens et l'usage excessif d'electricite contribuent aux changements climatiques et autres problemes environnementaux. Bien que plusieurs recherches rapportent que l'etre humain est de plus en plus conscient de ses impacts sur le climat de la planete, ces memes recherches indiquent qu'en general, les gens continuent a se comporter de facon non ecologique. Que ce soit a l'ecole ou dans la communaute, plusieurs chercheurs en education relative a l'environnement estiment qu'une personne bien intentionnee est capable d'adopter des comportements plus respectueux de l'environnement. Le but de cette these etait de comprendre le processus d'integration de comportements d'attenuation des changements climatiques dans des familles. A cette fin, nous nous sommes fixe deux objectifs : 1) decrire les competences et les procedes qui favorisent l'adoption de comportements d'attenuation des changements climatiques dans des familles et 2) decrire les facteurs et les dynamiques familiales qui facilitent et limitent l'adoption de comportements d'attenuation des changements climatiques dans des familles. Des familles ont ete invitees a essayer des comportements personnels et collectifs d'attenuation des changements climatiques de sorte a integrer des modes de vie plus ecologiques. Sur une periode de huit mois, nous avons suivi leur experience de changement afin de mieux comprendre comment se produit le processus de changement dans des familles qui decident volontairement d'adopter des comportements d'attenuation des changements climatiques. Apres leur avoir fourni quelques connaissances de base sur les changements climatiques, nous avons observe le vecu de changement des familles durant huit mois d'essais a l'aide de journaux reflexifs, d'entretiens d'explicitation et du journal du chercheur. La these comporte trois articles scientifiques. Dans le premier article, nous presentons une

  15. Dispositif de mesure calorimétrique des pertes dans les condensateurs de puissance

    NASA Astrophysics Data System (ADS)

    Seguin, B.; Gosse, J. P.

    1997-02-01

    A calorimetric technique is used to measure the power losses in capacitors. The power dissipated in the component is measured as the difference between the heat powers delivered by a temperature regulation when the capacitor is energetized or not. The original feature of the apparatus lies in the use of the isothermal calorimetry and in the measurement of an electrical power, in condradistinction with previous and dissatisfacting attempts based on the measurement of a temperature increase. The result is an improvement of the accuracy and sensibility of the apparatus which can be used to determine the equivalent series resistance of capacitors having very low losses. Measurements realized on a polypropylene capacitor and a sinusoidal applied voltage have allowed us to separate the ohmic losses from the dielectric ones and to study their variations with temperature. Une technique de calorimétrie isotherme est appliquée à la mesure des pertes électriques dans les condensateurs. La puissance calorifique dissipée par le composant est mesurée comme la différence des puissances de chauffe délivrées par une régulation de température quand le condensateur est hors tension ou sous tension. L'originalité du dispositif réside dans l'utilisation du principe de calorimétrie isotherme et dans la nature de la grandeur physique mesurée qui est une puissance électrique alors que les tentatives antérieures de mesures calorimétriques reposaient sur la mesure d'une élévation de température. Il en résulte une amélioration de la précision et de la sensibilité de ce type d'appareillage qui peut être employé pour caractériser la résistance série équivalente des condensateurs à très faibles pertes. Une série de mesures, réalisée sur un condensateur au polypropylène soumis à une tension sinusoïdale, a permis de séparer les pertes ohmiques des pertes diélectriques et d'étudier leurs variations avec la température.

  16. 17 CFR 41.15 - Exclusion from definition of narrow-based security index for indexes composed of debt securities.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... narrow-based security index for indexes composed of debt securities. 41.15 Section 41.15 Commodity and... Indexes § 41.15 Exclusion from definition of narrow-based security index for indexes composed of debt securities. (a) An index is not a narrow-based security index if: (1)(i) Each of the securities of an...

  17. 17 CFR 41.15 - Exclusion from definition of narrow-based security index for indexes composed of debt securities.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... narrow-based security index for indexes composed of debt securities. 41.15 Section 41.15 Commodity and... Indexes § 41.15 Exclusion from definition of narrow-based security index for indexes composed of debt securities. (a) An index is not a narrow-based security index if: (1)(i) Each of the securities of an...

  18. How Music Technology Can Make Sound and Music Worlds Accessible to Student Composers in Further Education Colleges

    ERIC Educational Resources Information Center

    Kardos, Leah

    2012-01-01

    I am a composer, producer, pianist and part-time music lecturer at a Further Education college where I teach composing on Music Technology courses at levels 3 (equivalent to A-level) and 4 (Undergraduate/Foundation Degree). A "Music Technology" course, distinct from a "Music" course, often attracts applicants from diverse musical backgrounds; it…

  19. Anisotropie des coefficients de diffusion dans des cristaux liquides discotiques hexagonaux

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Gharbia, M.; Gharbi, A.

    1994-06-01

    The diffusion constants of dyes in several hexagonal discotic liquid crystals are measured and discussed. For all the liquid crystals studied, these constants are anisotropic : the diffusion in the direction parallel to the columns is faster than that in the perpendicular plane (frac{D_allel}{D_perp}>1). The effects of the length and shape of the chains bound to the triphenylene discs are shown. The effect of the dye molecular size is also described. The study of the diffusion coefficients of hexapentoxytriphenylene (C5HET) as a function of temperature has shown that the activation energies along the columns and perpendicular to the columns are comparable. The main features of dye diffusion in the hexagonal columnar liquid crystals studied are similar to those reported in nematic phases. Les mesures des constantes de diffusion de colorants dans plusieurs cristaux liquides discotiques hexagonaux sont présentées et discutées. Pour tous les cristaux liquides étudiés, ces constantes présentent une anisotropie, avec une diffusion plus rapide parallèlement aux colonnes que perpendiculairement à celles-ci (frac{D_allel}{D_perp}>1). Des effets de longueur et de forme des chaînes branchées sur les disques de triphénylène sont mis en évidence. Il en est de même pour la taille des molécules de colorants. L'étude en fonction de la température a montré que dans le cas de l'hexapentoxytriphénylène (C5HET), les énergies d'activation dans les directions parallèle et perpendiculaire aux colonnes sont comparables. Les caractéristiques de la diffusion de colorants dans les cristaux liquides colonnaires hexagonaux étudiés sont semblables à celles des nématiques.

  20. Le traitement familial des enfants et des adolescents anorexiques : Des lignes directrices pour le médecin communautaire

    PubMed Central

    Findlay, S; Pinzon, J; Taddeo, D; Katzman, DK

    2010-01-01

    L’anorexie mentale (AM) est une maladie grave qui met la vie en danger et qui fait généralement son apparition pendant l’adolescence. Les données probantes au sujet du traitement optimal de l’AM chez les enfants et les adolescents sont en croissance, mais il reste beaucoup à apprendre. Même si les démarches thérapeutiques actuelles varient au Canada et ailleurs, les données jusqu’à présent indiquent que le traitement familial (TF) est le plus efficace pour les enfants et les adolescents anorexiques. Un élément essentiel du modèle de TF, c’est que les parents sont investis de la responsabilité de rétablir la santé physique de leur enfant et de s’assurer de la reprise complète de son poids. Le médecin qui comprend les principes fondamentaux et la philosophie du TF peut mettre en place les éléments de cette intervention fondée sur des faits probants auprès des jeunes patients anorexiques et de leur famille.

  1. Investigation of Plastic Zone Development in Dynamic Tear Test Specimens - Phase 2

    DTIC Science & Technology

    2000-09-01

    essats elastlques-plasttques et on a constate une concordance assez precise . Sommaire II est important de pouvOlr predire ]a taille des zones elastiques... precis de predire les defaillances. Nous avons done cherche a developper des modeles de zone plastique afin de definir le rapport entre le rayon de la...defmitwn de ce parametre nous permettra de defimr les vraies limites des essais sur les proprietes elastiques et plastiques des materiaux en ce qui

  2. Modelisation microstructurale en fatigue/fluage a froid des alliages de titane quasi alpha par le modele des automates cellulaires

    NASA Astrophysics Data System (ADS)

    Boutana, Mohammed Nabil

    Les proprietes d'emploi des alliages de titane sont extremement dependantes a certains aspects des microstructures developpees lors de leur elaboration. Ces microstructures peuvent etre fortement heterogenes du point de vue de leur orientation cristallographique et de leur repartition spatiale. Leurs influences sur le comportement du materiau et son endommagement precoce sont des questions qui sont actuellement soulevees. Dans le present projet de doctorat on chercher a repondre a cette question mais aussi de presenter des solutions tangibles quant a l'utilisation securitaire de ces alliages. Un nouveau modele appele automate cellulaire a ete developpe pour simuler le comportement mecanique des alliages de titane en fatigue-fluage a froid. Ces modeles ont permet de mieux comprendre la correlation entre la microstructure et le comportement mecanique du materiau et surtout une analyse detaillee du comportement local du materiau. Mots-cles: Automate cellulaire, fatigue/fluage, alliage de titane, inclusion d'Eshelby, modelisation

  3. Magnetic motion capture system using LC resonant magnetic marker composed of Ni-Zn ferrite core

    SciTech Connect

    Hashi, S.; Toyoda, M.; Ohya, M.; Okazaki, Y.; Yabukami, S.; Ishiyama, K.; Arai, K. I.

    2006-04-15

    We have proposed a magnetic motion capture system using an LC resonant magnetic marker. The proposed system is composed of an exciting coil, an LC marker, and a 5x5-matrix search coil array (25 search coils). The LC marker is small and has a minimal circuit with no battery and can be driven wirelessly by the action of electromagnetic induction. It consists of a Ni-Zn ferrite core (3 mm{phi}x10 mm) with a wound coil and a chip capacitor, forming an LC series circuit with a resonant frequency of 186 kHz. The relative position accuracy of the system is less than 1 mm within the area of 100 mm{sup 3} up to 150 mm from the search coil array. Compared with dc magnetic systems, the proposed system is applicable for precision motion capture in optically isolated spaces without magnetic shielding because the system is not greatly influenced by earth field noise.

  4. Analysis of instability of systems composed by dark and baryonic matter

    NASA Astrophysics Data System (ADS)

    Kremer, Gilberto M.; André, Raíla

    2016-10-01

    In this work, the dynamics of self-gravitating systems composed by dark and baryonic matter is analyzed. Searching for a description of this dynamics, a system of collisionless Boltzmann equations for the two constituents and the Poisson equation for the gravitational field are employed. Through the solution of these equations, the collapse criterion is determined from a dispersion relation. The collapse occurs in an unstable region where the solutions grow exponentially with time. It is shown that the unstable region becomes larger if the dispersion velocity of dark matter becomes larger than the one of the baryonic matter. The results obtained are also compared with the case where only the dark matter is present. The model of the present work has a higher limit of instability and therefore exhibited an advantage in the structure formation.

  5. Frequency selective reflection and transmission at a layer composed of a periodic dielectric

    NASA Technical Reports Server (NTRS)

    Bertoni, Henry L.; Cheo, Li-Hsiang S.; Tamir, Theodor

    1987-01-01

    The feasibility of using a periodic dielectric layer, composed of alternating bars having dielectric constants epsilon sub 1 and epsilon sub 2, as a frequency selective subreflector in order to permit feed separation in large aperture reflecting antenna systems was examined. For oblique incidence, it is found that total transmission and total reflection can be obtained at different frequencies for proper choices of epsilon sub 1, epsilon 2, and the geometric parameters. The frequencies of total reflection and transmission can be estimated from wave phenomena occurring in a layer of uniform dielectric constant equal to the average for the periodic layers. About some of the frequencies of total transmission, the bandwidth for 90% transmission is found to be 40%. However, the bandwidth for 90% reflection is always found to be much narrower; the greatest value found being 2.5%.

  6. Entanglement of two hybrid optomechanical cavities composed of BEC atoms under Bell detection

    NASA Astrophysics Data System (ADS)

    Eghbali-Arani, M.; Ameri, V.

    2017-02-01

    In this paper, firstly, we consider bipartite entanglement between each part of an optomechanical cavity composed of one-dimensional Bose-Einstein condensate (BEC). We investigate atomic collision on the behaviour of the BEC in the week photon-atom coupling constant and use Bogoliubov approximation for the BEC. Secondly under above condition, we propose a scheme for entanglement swapping protocol which involves tripartite systems. In our investigation, we consider a scenario where BECs, moving mirrors, and optical cavity modes are given in a Gaussian state with a covariance matrix. By applying the Bell measurement to the output optical field modes, we show how the remote entanglement between two BECs, two moving mirrors, and BEC-mirror modes in different optomechanical cavity can be generated.

  7. Reclassification of giant viruses composing a fourth domain of life in the new order Megavirales.

    PubMed

    Colson, Philippe; de Lamballerie, Xavier; Fournous, Ghislain; Raoult, Didier

    2012-01-01

    Interest in giant viruses has risen sharply since 2003, following the discovery of the Mimivirus and four other protist-infecting giant viruses that are linked to the nucleocytoplasmic large DNA viruses (NCLDVs). Despite considerable heterogeneity in hosts and genome sizes, the NCLDVs have been shown to be monophyletic based on analyses of their sequences and gene repertoires and recent studies have proposed that these viruses share a common ancient ancestor and compose a fourth domain of life. In addition, several characteristics of these giant viruses contradict or do not match the criteria used for the canonical definition of viruses, and the NCLDV denomination is not completely appropriate. We propose here to define a new viral order named Megavirales.

  8. Solid-liquid equilibria for binary mixtures composed of acenaphthene, dibenzofuran, fluorene, phenanthrene, and diphenylmethane

    SciTech Connect

    Lee, M.J.; Chen, C.H.; Lin, H.

    1999-09-01

    The liquidus lines were determined with a solid-disappearance method for binary mixtures composed of acenaphthene, dibenzofuran, fluorene, phenanthrene, and diphenylmethane. While the first four substances are model compounds of wash oil, which has widely been used as a solvent to remove aromatics from coal oven gas, diphenylmethane is a high-boiling and low-melting compound that is a potential additive to modify the performance of wash oil. Each of the seven binaries appears to be a simple eutectic system, as evidenced by the experimental results. The Wilson and the NRTL models were employed to correlate the solid-liquid equilibrium data. Both activity coefficient models were found to represent accurately the nonideality of the liquid-phase for the investigated systems.

  9. Sol-gel transition of charged fibrils composed of a model amphiphilic peptide.

    PubMed

    Owczarz, Marta; Bolisetty, Sreenath; Mezzenga, Raffaele; Arosio, Paolo

    2015-01-01

    We characterized the sol-gel transition of positively charged fibrils composed of the model amphiphilic peptide RADARADARADARADA (RADA 16-I) using a combination of microscopy, light scattering, microrheology and rheology techniques, and we investigated the dependence of the hydrogel formation on fibril concentration and ionic strength. The peptide is initially present as a dispersion of short rigid fibrils with average length of about 100 nm. During incubation, the fibrils aggregate irreversibly into longer fibrils and fibrillar aggregates. At peptide concentrations in the range 3-6.5 g/L, the fibrillar aggregates form a weak gel network which can be destroyed upon dilution. Percolation occurs without the formation of a nematic phase at a critical peptide concentration which decreases with increasing ionic strength. The gel structure can be well described in the frame of the fractal gel theory considering the network as a collection of fibrillar aggregates characterized by self-similar structure with a fractal dimension of 1.34.

  10. Ring chromosomes in dermatofibrosarcoma protuberans are composed of interspersed sequences from chromosomes 17 and 22.

    PubMed Central

    Naeem, R.; Lux, M. L.; Huang, S. F.; Naber, S. P.; Corson, J. M.; Fletcher, J. A.

    1995-01-01

    Ring chromosomes are found in most dermatofibrosarcoma protuberans (DFSPs), and recent reports demonstrate that portions of the DFSP ring chromosomes derive from chromosome 17. In this study we characterized ring chromosomes in three DFSPs using a combined approach of karyotyping, chromosome painting, and comparative genomic hybridization. Chromosome painting demonstrated that the ring chromosomes in each DFSP were composed of discontinuous, interwoven sequences from chromosomes 17 and 22. Amplification of chromosomes 17 and 22 sequences was confirmed in each of these cases by comparative genomic hybridization, and over-representation of chromosomes 17 and 22 sequences was also demonstrated by comparative genomic hybridization in 1 of 2 cytogenetically unremarkable DFSPs. We conclude that amplification of chromosomes 17 and 22 sequences, in ring form, is a characteristic aberration in DFSP. Images Figure 1 Figure 2 PMID:7495279

  11. Formation and Characterization of Supported Lipid Bilayers Composed of Hydrogenated and Deuterated Escherichia coli Lipids

    PubMed Central

    Lind, Tania Kjellerup; Wacklin, Hanna; Schiller, Jürgen; Moulin, Martine; Haertlein, Michael; Pomorski, Thomas Günther; Cárdenas, Marité

    2015-01-01

    Supported lipid bilayers are widely used for sensing and deciphering biomolecular interactions with model cell membranes. In this paper, we present a method to form supported lipid bilayers from total lipid extracts of Escherichia coli by vesicle fusion. We show the validity of this method for different types of extracts including those from deuterated biomass using a combination of complementary surface sensitive techniques; quartz crystal microbalance, neutron reflection and atomic force microscopy. We find that the head group composition of the deuterated and the hydrogenated lipid extracts is similar (approximately 75% phosphatidylethanolamine, 13% phosphatidylglycerol and 12% cardiolipin) and that both samples can be used to reconstitute high-coverage supported lipid bilayers with a total thickness of 41 ± 3 Å, common for fluid membranes. The formation of supported lipid bilayers composed of natural extracts of Escherichia coli allow for following biomolecular interactions, thus advancing the field towards bacterial-specific membrane biomimics. PMID:26658241

  12. Antimicrobial effect of medical adhesive composed of aldehyded dextran and ε-Poly(L-Lysine).

    PubMed

    Lee, Jeong-Hyun; Kim, Hye-Lee; Lee, Mi Hee; Taguchi, Hideaki; Hyon, Suong-Hyu; Park, Jong-Chul

    2011-11-01

    Infection of surgical wounds is a severe problem. Conventional tissue reattachment methods have limits of incomplete sealing and high susceptibility to infection. Medical adhesives have several advantages over traditional tissue reattachment techniques, but still have drawbacks, such as the probability of infection, low adhesive strength, and high cytotoxicity. Recently, a new medical adhesive (new-adhesive) with high adhesive strength and low cytotoxicity, composed of aldehyded dextran and ε-poly(L-lysine), was developed. The antimicrobial activity of the new-adhesive was assayed using agar media and porcine skin. In the agar diffusion method, inoculated microorganisms that contacted the new-adhesive were inactivated, but this was not dependent on the amount of new-adhesive. Similar to the agar media results, the topical antimicrobial effect of new-adhesive was confirmed using a porcine skin antimicrobial assay, and the effect was not due to physical blocking based on comparison with the group whose wounds were wrapped.

  13. Mechanical properties of artificial tracheas composed of a mesh cylinder and a spiral stent.

    PubMed

    Kawaguchi, S; Nakamura, T; Shimizu, Y; Masuda, T; Takigawa, T; Liu, Y; Ueda, H; Sekine, T; Matsumoto, K

    2001-12-01

    Much work has been done on the materials used for mesh-type artificial tracheas, but a precise mechanical evaluation of these structures has not yet been performed. In the present study, we determined the mechanical properties of typical mesh-type artificial tracheas and compared them with those of native trachea. Four types of artificial trachea were made and used for the mechanical tests. The basic frame of all the specimens was composed of a mesh cylinder and a spiral stent. The specimen whose mesh was sealed with collagen sponge showed almost the same behavior in the force-strain curve under compression, suggesting that collagen sealing has little effect on mechanical properties. Agreement between measured and estimated mechanical properties was good, especially in the low strain region, suggesting that artificial tracheas can be designed in terms of mechanical properties by mainly considering the basic frame structure.

  14. [Fuzzy mathematic quantitative law of composing principle in the study of traditional Chinese medicine].

    PubMed

    Liu, Ming; Gao, Yue; Xiao, Rui; Zhang, Bo-li

    2009-01-01

    This study is to analyze microcosmic significance of Chinese medicine composing principle "principal, assistant, complement and mediating guide" and it's fuzzy mathematic quantitative law. According to molecular biology and maximal membership principle, fuzzy subset and membership functions were proposed. Using in vivo experiment on the effects of SiWu Decoction and its ingredients on mice with radiation-induced blood deficiency, it is concluded that DiHuang and DangGui belonged to the principal and assistant subset, BaiShao belonged to the contrary complement subset, ChuanXiong belonged to the mediating guide subset by maximal membership principle. It is discussed that traditional Chinese medicine will be consummate medical science when its theory can be described by mathematic language.

  15. Implementation of Kane's Method for a Spacecraft Composed of Multiple Rigid Bodies

    NASA Technical Reports Server (NTRS)

    Stoneking, Eric T.

    2013-01-01

    Equations of motion are derived for a general spacecraft composed of rigid bodies connected via rotary (spherical or gimballed) joints in a tree topology. Several supporting concepts are developed in depth. Basis dyads aid in the transition from basis-free vector equations to component-wise equations. Joint partials allow abstraction of 1-DOF, 2-DOF, 3-DOF gimballed and spherical rotational joints to a common notation. The basic building block consisting of an "inner" body and an "outer" body connected by a joint enables efficient organization of arbitrary tree structures. Kane's equation is recast in a form which facilitates systematic assembly of large systems of equations, and exposes a relationship of Kane's equation to Newton and Euler's equations which is obscured by the usual presentation. The resulting system of dynamic equations is of minimum dimension, and is suitable for numerical solution by computer. Implementation is ·discussed, and illustrative simulation results are presented.

  16. Propagation of elastic waves in two-dimensional phononic crystals composed of viscoelastic materials

    NASA Astrophysics Data System (ADS)

    Tanaka, Yukihiro; Tomioka, Shunsuke; Shimomura, Yukito; Nishiguchi, Norihiko

    2017-03-01

    We have investigated the transmission characteristics of acoustic waves through two-dimensional phononic crystals composed of viscoelastic materials such as silicon rubber. In the present work, we improve a previously proposed method in which it was assumed that the Poisson ratio of silicon rubber is independent of time. The improved method removes the assumption and independently handles two parameters that describe a viscoelastic material: time-dependent bulk modulus and shear rate. We find that the time-dependent shear rates can modulate the frequency dependences of the transmission rate to various degrees. Therefore, in acoustic wave transmission, we can obtain large gaps in the audible domain by choosing the substrate material appropriately. In addition, we find that the viscoelasticity of the substrate makes the fine structure for the transmission rates smooth.

  17. In vivo absorption of didanosine formulated in pellets composed of chitosan microspheres.

    PubMed

    Severino, Patrícia; Da Silva, Classius Ferreira; Dalla Costa, Teresa Cristina T; Silva, Heloisa; Chaud, Marco V; Santana, Maria Helena A; Souto, Eliana B

    2014-01-01

    The in vivo absorption of didanosine was studied, focusing on the performance of a novel pharmaceutical formulation for didanosine, composed of chitosan granules containing didanosine incorporated in chitosan microspheres. This novel formulation is aimed at oral administration in AIDS therapy. The experimental results in male adult dogs showed controlled delivery of didanosine along 36 h, with a 2-fold increase in the absorption time of didanosine compared to the commercial granules, gastro-resistant didanosine and tablets. The higher absorption is due to adhesion to the intestinal membrane, improving absorption through increase of residence time, permeation and release. Furthermore, the novel formulation facilitates handling and deglutition, especially in the elderly and children, as well as enhances the taste and reduces the frequency of doses and collateral effects associated with a high concentration of the buffer agents usually used in other formulations.

  18. In-depth calibration of a Laue lens prototype composed of Fe and Al mosaic crystals

    NASA Astrophysics Data System (ADS)

    Wade, Colin; Barrière, Nicolas; Tomsick, John A.; Hanlon, Lorraine; Boggs, Steven E.; Brejnholt, Nicolai F.; Massahi, Sonny; Von Ballmoos, Peter

    2016-07-01

    The Laue lens is a developing technology for focusing soft gamma-rays, that is based on the principle of Bragg diffraction. A suitable arrangement of diffracting crystals is used to concentrate a set of parallel incoming photons onto a common focal spot. In late 2014, the Laue lens assembly station (LLAS) at UC Berkeley was used to construct a prototype lens segment, consisting of 48 5 x 5mm2 crystals - 36 iron and 12 aluminium. The segment is composed of 8 partial rings, each of which is aligned to diffract an energy between 90 and 130 keV. In December 2015 the prototype was tested and calibrated using the LLAS and results are presented here. The crystal mounting speed, accuracy of crystal position and orientation, and crystal reflectivity are addressed.

  19. Formation and Characterization of Supported Lipid Bilayers Composed of Hydrogenated and Deuterated Escherichia coli Lipids.

    PubMed

    Lind, Tania Kjellerup; Wacklin, Hanna; Schiller, Jürgen; Moulin, Martine; Haertlein, Michael; Pomorski, Thomas Günther; Cárdenas, Marité

    2015-01-01

    Supported lipid bilayers are widely used for sensing and deciphering biomolecular interactions with model cell membranes. In this paper, we present a method to form supported lipid bilayers from total lipid extracts of Escherichia coli by vesicle fusion. We show the validity of this method for different types of extracts including those from deuterated biomass using a combination of complementary surface sensitive techniques; quartz crystal microbalance, neutron reflection and atomic force microscopy. We find that the head group composition of the deuterated and the hydrogenated lipid extracts is similar (approximately 75% phosphatidylethanolamine, 13% phosphatidylglycerol and 12% cardiolipin) and that both samples can be used to reconstitute high-coverage supported lipid bilayers with a total thickness of 41 ± 3 Å, common for fluid membranes. The formation of supported lipid bilayers composed of natural extracts of Escherichia coli allow for following biomolecular interactions, thus advancing the field towards bacterial-specific membrane biomimics.

  20. Filters based on spoof surface plasmon polaritons composed of planar Mach-Zehnder interferometer

    NASA Astrophysics Data System (ADS)

    Xiao, Binggang; Chen, Jing; Kong, Sheng

    2016-08-01

    Filter characteristics of a planar Mach-Zehnder interferometer (MZI) structure composed of periodically thin corrugated metal films were studied here. From theoretical simulation, spoof surface plasmon polaritons can propagate along the periodically thin corrugated metal films in microwave frequency, which can be excited by a coplanar waveguide. When the two arms of the MZI have the same length with the angle between them being 60°, the MZI structure has a very wide bandwidth with 8.6 GHz. By changing the length of one of the interference arms, a novel low-pass filter based on the planar MZI structure with two notched frequencies was proposed. The proposed planar structure can find potential applications in developing surface wave devices in integrated microwave circuits and systems.

  1. Theoretical prediction of some novel nanotubes composed of macrocyclic structures: A DFT study

    NASA Astrophysics Data System (ADS)

    Masoodi, Hamid Reza; Bagheri, Sotoodeh; Ranjbar-Karimi, Reza

    2017-01-01

    Our interests in this paper are the elucidation of structural and electronic properties of some π-conjugated macrocycles composed of borazine and alumazene rings as well as the investigation of their potential utility for the creation of new nanotubes. Here, the calculations are performed at B3LYP/6-31+G(d) and M06-2X/6-31+G(d)//B3LYP/6-31+G(d) levels of theory. The results suggest that the self-assembly of the macrocyclic compounds can be considered to form new nanotubes through π-π stacking. Also, meaningful correlations are found between the stability and photoconductivity applications of the nanotubes and the number of stacked π-conjugated macrocycles.

  2. A genetic pathway composed of Sox14 and Mical governs severing of dendrites during pruning

    PubMed Central

    Kirilly, Daniel; Gu, Ying; Huang, Yafen; Wu, Zhuhao; Bashirullah, Arash; Low, Boon Chuan; Kolodkin, Alex L; Wang, Hongyan; Yu, Fengwei

    2011-01-01

    Pruning that selectively eliminates neuronal processes is crucial for the refinement of neural circuits during development. In Drosophila, the class IV dendritic arborization neuron (ddaC) undergoes pruning to remove its larval dendrites during metamorphosis. We identified Sox14 as a transcription factor that was necessary and sufficient to mediate dendrite severing during pruning in response to ecdysone signaling. We found that Sox14 mediated dendrite pruning by directly regulating the expression of the target gene mical. mical encodes a large cytosolic protein with multiple domains that are known to associate with cytoskeletal components. mical mutants had marked severing defects during dendrite pruning that were similar to those of sox14 mutants. Overexpression of Mical could significantly rescue pruning defects in sox14 mutants, suggesting that Mical is a major downstream target of Sox14 during pruning. Thus, our findings indicate that a previously unknown pathway composed of Sox14 and its cytoskeletal target Mical governs dendrite severing. PMID:19881505

  3. Nanostructure characterization and performance evaluation of perovskite sensor composed of multi-elements.

    PubMed

    Pan, Xubin; Bashir, Sajid; Liang, Gang; Liu, Jingbo Louise

    2010-06-15

    A multi-element perovskite nanoscale film composed of Li(+) cation incorporated into Ca(2+)-doped PbTiO(3) (LCPT) was derived via colloidal chemistry, sol-gel (SG) method followed by heat-treatment. The morphology, chemical composition and structure of the LCPT nanofilms were investigated by advanced instrumentation (microscopy and spectroscopy) techniques. The characterization indicates formation of a tetragonal crystalline ceramic after sintering. The humidity sensing performances of LCPT nanofilms with various formulations were evaluated as a function of lattice distortion. The LCPT sensor doped with Li (0.5-0.1mol%) possessed the distortion of 1.041-1.046 and displayed rapid sensitivity (current changes from 1.5x10(-3) to 5.2A), high linearity (R(2)=0.997) in the whole relative humidity range (phi: 8-93% RH) under low frequency of 100Hz, and excellent long-term stability.

  4. Hydration kinetics of cementitious materials composed of red mud and coal gangue

    NASA Astrophysics Data System (ADS)

    Zhang, Na; Li, Hong-xu; Liu, Xiao-ming

    2016-10-01

    To elucidate the intrinsic reaction mechanism of cementitious materials composed of red mud and coal gangue (RGC), the hydration kinetics of these cementitious materials at 20°C was investigated on the basis of the Krstulović-Dabić model. An isothermal calorimeter was used to characterize the hydration heat evolution. The results show that the hydration of RGC is controlled by the processes of nucleation and crystal growth (NG), interaction at phase boundaries (I), and diffusion (D) in order, and the pozzolanic reactions of slag and compound-activated red mud-coal gangue are mainly controlled by the I process. Slag accelerates the clinker hydration during NG process, whereas the compound-activated red mud-coal gangue retards the hydration of RGC and the time required for I process increases with increasing dosage of red mud-coal gangue in RGC.

  5. A robust nanoscale biomemory device composed of recombinant azurin on hexagonally packed Au-nano array.

    PubMed

    Yagati, Ajay Kumar; Lee, Taek; Min, Junhong; Choi, Jeong-Woo

    2013-02-15

    We developed a nanoscale memory device consisting of signal-responsive biomaterial, which is capable of switching physical properties (such as electrical/electrochemical, optical, and magnetic) upon application of appropriate electrical signals to perform memory switching. Here, we propose a highly robust surface-confined switch composed of an electroactive cysteine-modified azurin immobilized on an Au hexagonal pattern formed on indium tin oxide (ITO) substrates that can be controlled electrochemically and reversibly converted between its redox states. The memory effect is based on conductance switching, which leads to the occurrence of bistable states and behaves as an extremely robust redox switch in which an electrochemical input is transduced into optical and magnetic outputs under ambient conditions. The fact that this molecular surface switch, operating at very low voltages, can be patterned and addressed locally, and also has good stability and excellent reversibility, makes it a promising platform for nonvolatile memory devices.

  6. Pharmacokinetics of Polymersomes Composed of Poly(Butadiene-Ethylene Oxide); Healthy versus Tumor-Bearing Mice.

    PubMed

    Wang, G; de Kruijff, R M; Abou, D; Ramos, N; Mendes, E; Franken, L E; Wolterbeek, H T; Denkova, A G

    2016-02-01

    Vesicles composed of block copolymers (i.e., polymersomes) are one of the most versatile nano-carriers for medical purposes due to their tuneable physicochemical properties and the possibility to encapsulate simultaneously hydrophobic and hydrophilic substances, allowing, for instance, the combination of therapy and imaging. In cancer treatment, these vesicles need to remain long enough in the blood stream to be sufficiently taken up by tumors. Here, we have investigated the biodistribution and the pharmacokinetics of polymersomes, composed of poly(butadiene-b-ethylene oxide) having dimensions around 80 nm. The polymersomes have been radiolabeled with ¹¹¹In via the so-called active loading method achieving a loading efficiency of 92.9 ± 0.9% with radionuclide retention in mouse serum of more than 95% at 24 h. The optimized ¹¹¹In containing polymersomes have been intravenously administered in healthy and tumor bearing mice for pharmacokinetic determination using microSPECT (Single Photon Emission Computed Tomography). In healthy mice these polymersomes have been found to exhibit relatively long blood circulation (> 6 h), low liver uptake (6 ± 1.5%ID/g, 48 h p.i.) and elevated spleen uptake (188 ± 30%ID/g). The blood circulation in tumor bearing mice is dramatically reduced (< 1.5 h) most likely due to elevated splenic filtration, clearly indicating the importance of in vivo studies in diseased mice. Finally, the polymersomes have been injected subcutaneously in tumor bearing mice revealing retention of 77% in the mice, primarily accumulated at the site of injection, up to 48 hours after administration.

  7. Construction of cuprous oxide electrodes composed of 2D single-crystalline dendritic nanosheets.

    PubMed

    Jang, Ho Seong; Kim, Suk Jun; Choi, Kyoung-Shin

    2010-10-04

    An unusual anisotropic growth of Cu(2)O is stabilized via the electrochemical synthesis of Cu(2)O in the presence of Ag(+) ions, which results in the formation of Cu(2)O electrodes composed of 2D sheetlike crystals containing complex dendritic patterns. It is quite unusual for Cu(2)O to form a 2D morphology since it has a 3D isotropic cubic crystal structure where the a, b, and c axes are equivalent. Each Cu(2)O sheet is single-crystalline in nature and is grown parallel to the {110} plane, which is rarely observed in Cu(2)O crystal shapes. A various set of experiments are performed to understand the role of Ag(+) ions on the 2D growth of Cu(2)O. The results show that Ag(+) ions are deposited as silver islands on already growing Cu(2)O crystals and serve as nucleation sites for the new growth of Cu(2)O crystals. As a result, the growth direction of the newly forming Cu(2)O crystals is governed by the diffusion layer structure created by the pre-existing Cu(2)O crystals, which results in the formation of 2D dendritic patterns. The thin 2D crystal morphology can significantly increase the surface-to-volume ratio of Cu(2)O crystals, which is beneficial for enhancing various electrochemical and photoelectrochemical properties of the electrodes. The photoelectrochemical properties of the Cu(2)O electrodes composed of 2D dendritic crystals are investigated and compared to those of 3D dendritic crystals. This study provides a unique and effective route to maximize the {110} area per unit volume of Cu(2)O, which will be beneficial for any catalytic/sensing abilities that can be anisotropically enhanced by the {110} planes of Cu(2)O.

  8. Experimental evolution of a green fluorescent protein composed of 19 unique amino acids without tryptophan.

    PubMed

    Kawahara-Kobayashi, Akio; Hitotsuyanagi, Mitsuhiro; Amikura, Kazuaki; Kiga, Daisuke

    2014-04-01

    At some stage of evolution, genes of organisms may have encoded proteins that were synthesized using fewer than 20 unique amino acids. Similar to evolution of the natural 19-amino-acid proteins GroEL/ES, proteins composed of 19 unique amino acids would have been able to evolve by accumulating beneficial mutations within the 19-amino-acid repertoire encoded in an ancestral genetic code. Because Trp is thought to be the last amino acid included in the canonical 20-amino-acid repertoire, this late stage of protein evolution could be mimicked by experimental evolution of 19-amino-acid proteins without tryptophan (Trp). To further understand the evolution of proteins, we tried to mimic the evolution of a 19-amino-acid protein involving the accumulation of beneficial mutations using directed evolution by random mutagenesis on the whole targeted gene sequence. We created active 19-amino-acid green fluorescent proteins (GFPs) without Trp from a poorly fluorescent 19-amino-acid mutant, S1-W57F, by using directed evolution with two rounds of mutagenesis and selection. The N105I and S205T mutations showed beneficial effects on the S1-W57F mutant. When these two mutations were combined on S1-W57F, we observed an additive effect on the fluorescence intensity. In contrast, these mutations showed no clear improvement individually or in combination on GFPS1, which is the parental GFP mutant composed of 20 amino acids. Our results provide an additional example for the experimental evolution of 19-amino-acid proteins without Trp, and would help understand the mechanisms underlying the evolution of 19-amino-acid proteins. (236 words).

  9. Wettability of polymeric solids by ternary mixtures composed of hydrocarbon and fluorocarbon nonionic surfactants.

    PubMed

    Szymczyk, Katarzyna

    2011-11-01

    Contact angle (θ) measurements on poly(tetrafluoroethylene) (PTFE) and polymethyl methacrylate (PMMA) surface were carried out for the systems containing ternary mixtures of surfactants composed of: p-(1,1,3,3-tetramethylbutyl)phenoxypoly(ethylene glycols), Triton X-100 (TX100), Triton X-165 (TX165) and Triton X-114 (TX114), and fluorocarbon surfactants, Zonyl FSN100 (FSN100) and Zonyl FSO100 (FSO100). The aqueous solutions of ternary surfactant mixtures were prepared by adding TX114, FSN100 or FSO100 to binary mixtures of TX100+TX165, where the synergistic effect in the reduction of the surface tension of water (γ(LV)) was determined. From the obtained contact angle values, the relationships between cosθ, the adhesion tension and surface tension of solutions, cosθ and the reciprocal of the surface tension were determined. On the basis of these relationships, the correlation between the critical surface tension of PTFE and PMMA wetting and the surface tension of these polymers as well as the work of adhesion of aqueous solutions of ternary surfactant mixtures to PTFE and PMMA surface were discussed. The critical surface tension of PTFE and PMMA wetting, γ(C), determined from the contact angle measurements of aqueous solutions of surfactants including FSN100 or FSO100 was also discussed in the light of the surface tension changes of PTFE and PMMA under the influence of film formation by fluorocarbon surfactants on the surface of these polymers. The γ(C) values of the studied polymeric solids were found to be different for the mixtures composed of hydrocarbon surfactants in comparison with those of hydrocarbon and fluorocarbon surfactants. In the solutions containing fluorocarbon surfactants, the γ(C) values were different taking into account the contact angle in the range of FSN100 and FSO100 concentration corresponding to their unsaturated monolayer at water-air interface or to that saturated.

  10. A Novel Approach to Beam Steering Using Arrays Composed of Multiple Unique Radiating Modes

    NASA Astrophysics Data System (ADS)

    Labadie, Nathan Richard

    Phased array antennas have found wide application in both radar and wireless communications systems particularly as implementation costs continue to decrease. The primary advantages of electronically scanned arrays are speed of beam scan and versatility of beamforming compared to mechanically scanned fixed beam antennas. These benefits come at the cost of a few well known design issues including element pattern rolloff and mutual coupling between elements. Our primary contribution to the field of research is the demonstration of significant improvement in phased array scan performance using multiple unique radiating modes. In short, orthogonal radiating modes have minimal coupling by definition and can also be generated with reduced rolloff at wide scan angles. In this dissertation, we present a combination of analysis, full-wave electromagnetic simulation and measured data to support our claims. The novel folded ring resonator (FRR) antenna is introduced as a wideband and multi-band element embedded in a grounded dielectric substrate. Multiple radiating modes of a small ground plane excited by a four element FRR array were also investigated. A novel hemispherical null steering antenna composed of two collocated radiating elements, each supporting a unique radiating mode, is presented in the context of an anti-jam GPS receiver application. Both the antenna aperture and active feed network were fabricated and measured showing excellent agreement with analytical and simulated data. The concept of using an antenna supporting multiple radiating modes for beam steering is also explored. A 16 element hybrid linear phased array was fabricated and measured demonstrating significantly improved scan range and scanned gain compared to a conventional phased array. This idea is expanded to 2 dimensional scanning arrays by analysis and simulation of a hybrid phased array composed of novel multiple mode monopole on patch antenna sub-arrays. Finally, we fabricated and

  11. Experimental Evolution of a Green Fluorescent Protein Composed of 19 Unique Amino Acids without Tryptophan

    NASA Astrophysics Data System (ADS)

    Kawahara-Kobayashi, Akio; Hitotsuyanagi, Mitsuhiro; Amikura, Kazuaki; Kiga, Daisuke

    2014-04-01

    At some stage of evolution, genes of organisms may have encoded proteins that were synthesized using fewer than 20 unique amino acids. Similar to evolution of the natural 19-amino-acid proteins GroEL/ES, proteins composed of 19 unique amino acids would have been able to evolve by accumulating beneficial mutations within the 19-amino-acid repertoire encoded in an ancestral genetic code. Because Trp is thought to be the last amino acid included in the canonical 20-amino-acid repertoire, this late stage of protein evolution could be mimicked by experimental evolution of 19-amino-acid proteins without tryptophan (Trp). To further understand the evolution of proteins, we tried to mimic the evolution of a 19-amino-acid protein involving the accumulation of beneficial mutations using directed evolution by random mutagenesis on the whole targeted gene sequence. We created active 19-amino-acid green fluorescent proteins (GFPs) without Trp from a poorly fluorescent 19-amino-acid mutant, S1-W57F, by using directed evolution with two rounds of mutagenesis and selection. The N105I and S205T mutations showed beneficial effects on the S1-W57F mutant. When these two mutations were combined on S1-W57F, we observed an additive effect on the fluorescence intensity. In contrast, these mutations showed no clear improvement individually or in combination on GFPS1, which is the parental GFP mutant composed of 20 amino acids. Our results provide an additional example for the experimental evolution of 19-amino-acid proteins without Trp, and would help understand the mechanisms underlying the evolution of 19-amino-acid proteins. (236 words)

  12. A case study of the influences of audience and purpose on the composing processes of an engineer

    NASA Technical Reports Server (NTRS)

    Stalnaker, B. J.

    1981-01-01

    The design and preliminary findings of a study of composing processes (on the job) of engineers, managers, and scientists is presented. The influences of audience and purpose on the composing process of engineers was of concern; specifically, the cognitive processes, physical behaviors, and factors that influence the evoluton of a piece of writing. An overview of the study, related literature, outlines of research design, and preliminary findings from a case study of engineers are given. It is suggested that teaching be adapted to help students learn to represent rhetorical problems to guide composing for effective writing.

  13. Annual Program Management Report 1989: Des Moines Recreational River and Greenbelt, Des Moines River, Iowa

    DTIC Science & Technology

    1989-10-01

    Rock Island District EXECUTIVE SUMMARY The General Design Memorandum (GDM) and Programmatic Environmental Impact Statement for the Des Moines...River and Greenbelt Programmatic Environmental Impact Statement. 40 Recommended for Preoaration of Feature Design Memoranda Bellville Overlook Sever...of the dam and lake is a wasteful expenditure of public money and would have extreme adverse impact on the environment in the area. The area is now

  14. Developpement d'une methode calorimetrique de mesure des pertes ac pour des rubans supraconducteurs a haute temperature critique

    NASA Astrophysics Data System (ADS)

    Dolez, Patricia

    Le travail de recherche effectue dans le cadre de ce projet de doctorat a permis la mise au point d'une methode de mesure des pertes ac destinee a l'etude des supraconducteurs a haute temperature critique. Pour le choix des principes de cette methode, nous nous sommes inspires de travaux anterieurs realises sur les supraconducteurs conventionnels, afin de proposer une alternative a la technique electrique, presentant lors du debut de cette these des problemes lies a la variation du resultat des mesures selon la position des contacts de tension sur la surface de l'echantillon, et de pouvoir mesurer les pertes ac dans des conditions simulant la realite des futures applications industrielles des rubans supraconducteurs: en particulier, cette methode utilise la technique calorimetrique, associee a une calibration simultanee et in situ. La validite de la methode a ete verifiee de maniere theorique et experimentale: d'une part, des mesures ont ete realisees sur des echantillons de Bi-2223 recouverts d'argent ou d'alliage d'argent-or et comparees avec les predictions theoriques donnees par Norris, nous indiquant la nature majoritairement hysteretique des pertes ac dans nos echantillons; d'autre part, une mesure electrique a ete realisee in situ dont les resultats correspondent parfaitement a ceux donnes par notre methode calorimetrique. Par ailleurs, nous avons compare la dependance en courant et en frequence des pertes ac d'un echantillon avant et apres qu'il ait ete endommage. Ces mesures semblent indiquer une relation entre la valeur du coefficient de la loi de puissance modelisant la dependance des pertes avec le courant, et les inhomogeneites longitudinales du courant critique induites par l'endommagement. De plus, la variation en frequence montre qu'au niveau des grosses fractures transverses creees par l'endommagement dans le coeur supraconducteur, le courant se partage localement de maniere a peu pres equivalente entre les quelques grains de matiere

  15. Des agents de santé communautaires pour la promotion de la santé des pasteurs nomades au Mali.

    PubMed

    Ag Ahmed, Mohamed Ali

    2016-12-01

    Au Mali, les nomades (des Maures, Touaregs et Peulhs) représentent environ 1,25 million de personnes. Les services de santé leur sont peu accessibles en raison de leur mobilité, liée à leur activité d'élevage. La question que se posent plusieurs intervenants en santé publique des pays où vivent ces nomades est de savoir comment améliorer leur santé. Dans ce commentaire, après un bref exposé des problèmes liés à l'accès aux services de santé, nous proposons une approche innovante et holistique de la santé, qui soutient que des agents de santé communautaires (ASC) pourraient contribuer à améliorer la santé des nomades en offrant conjointement des services de santé aux nomades et à leurs animaux (le concept « One Health » [d'Une Seule Santé]). Des pistes de réflexion sont dégagées, quant aux principaux défis pour leur efficacité et durabilité, qui sont la conception et gestion du programme, leur soutien par les communautés et leur intégration aux services de santé publique et vétérinaire.

  16. Evaluation des connaissances des parents sur les bronchiolites aiguës

    PubMed Central

    Gueddari, Widad; Tazi, Abderrahmane; Ouardi, Amine; Nani, Samira; Zineddine, Abdelhadi

    2014-01-01

    Les infections respiratoires (IR) constituent la deuxième cause de mortalité infantile au Maroc, dû en partie à l'absence d'information et de sensibilisation. Le but de ce travail était d’évaluer les connaissances des parents sur la bronchiolite aiguë, infection respiratoire très fréquente. Nous avons réalisé une enquête basée sur un questionnaire, auprès de parents de nourrissons consultants pour toux, avec ou sans gêne respiratoire. 180 parents ont été inclus dans l’étude. Les parents pensaient que l'infection respiratoire était secondaire au climat froid (96%); seuls 4% ont évoqué une origine infectieuse. Aucun des parents ne savait que le lavage des mains était un moyen de prévention de la transmission. Les parents ont majoritairement répondu que la kinésithérapie respiratoire ne servait à rien (65%), et qu'elle était nocive (24.5%). Ce manque de connaissances fondamentales en matière d'IR et de bronchiolite en particulier, devrait inciter à entreprendre un programme de sensibilisation PMID:25328606

  17. Sécurité au-delà des mythes et des croyances

    ScienceCinema

    None

    2016-07-12

    Présentation orale en français, support visuel en français et en anglais. La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l’on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

  18. Investigation on hardness and impact resistance of automotive brake pad composed with rice husk dust

    NASA Astrophysics Data System (ADS)

    Bahari, Shahril Anuar; Isa, Khairul Hafizee; Kassim, Masitah Abu; Mohamed, Zulkifli; Othman, Eliasidi Abu

    2012-06-01

    In this study, hardness and impact resistance properties of automotive brake pad composed with rice husk dust (RHD) were documented. RHD was mixed with other metallic and synthetic ingredients of automotive brake pad. To obtain RHD, rice husk was ground and dried to 1 - 3% moisture content. The RHD was screened to obtain different dust sizes (80 and 100-mesh) before it was mixed with other materials at different percentages of composition (10 and 30%). The mixture was then pressed to produce brake pad. Rockwell hardness testing machine was used in hardness determination, while Izod impact testing machine was used in impact resistance determination. Hardness resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was significantly higher than 100-mesh. Hardness resistance of automotive brake pad mixed with 30% composition and 100-mesh size of RHD was slightly higher than 80 mesh. However, based on analysis, the difference was not significant. According to the result, hardness resistance of automotive brake pad mixed with 30% composition of RHD was higher than 10%. RHD has filled up the space and enhanced the micro structural behaviour of automotive brake pad. Impact resistance of automotive brake pad mixed with 10% composition and 80-mesh size of RHD was insignificantly higher than 100-mesh. Impact resistance of automotive brake pad mixed with 30% composition and 80-mesh size of RHD was significantly higher than 100 mesh. Large RHD size has increased the capability to resist high-rated impact loading. The impact energy was distributed over wider area for larger particle size. This factor has increased the impact resistance of automotive brake pad from large dust size. Impact resistance of automotive brake pad mixed with 80-mesh size and 30% composition of RHD was higher than 10%. In contrast, impact resistance of automotive brake pad mixed with 100-mesh size and 10% composition of RHD was higher than 30%. However, the difference was not

  19. Modélisation des boucles d'immunisation magnétique des navires

    NASA Astrophysics Data System (ADS)

    Le Dorze, F.; Bongiraud, J. P.; Coulomb, J. L.; Meunier, G.; Brunotte, X.

    1998-02-01

    This paper presents the problem of the three-dimensional modeling of degaussing coils in ships with a finite elements method. We show that these current coils are so close to the ferromagnetic sheets of the ship that they require a local very fine mesh which would be unrealistic for the whole complex structure of a real ship. We propose an alternative to the expensive mesh refinement called "reduced scalar potential jump”. The idea is to previously solve the local problem by another method and to use the result in the whole FEM modelling. We present the method of implementation in the FEM software FLUX3D and comparative results on a simple geometry. Cet article présente le problème de la modélisation en trois dimensions des boucles d'immunisation des navires par la méthode des éléments finis. Nous montrons que ces boucles de courant sont si proches des tôles ferromagnétiques du navire que leur modélisation requiert un maillage localement très fin, ce qui est irréaliste pour la structure complexe d'un navire réel. Nous proposons une alternative à ce coûteux affinage du maillage, appelée "saut de potentiel réduit”. L'idée est de résoudre au préalable le problème local par une autre méthode que les éléments finis et d'utiliser le résultat dans la modélisation globale. Nous présentons la méthode utilisée pour l'implantation de cette technique dans le logiciel d'éléments finis FLUX3D, et des résultats comparatifs sur une géométrie simple.

  20. Formation et Evolution des Quasars et Contraintes cosmologiques

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, Evanthia

    2000-06-01

    Cette thèse porte sur l'étude de l'évolution des quasars. Elle en aborde certains aspects théoriques et observationnels, ainsi que la construction des grands échantillons de quasars dans le but à long terme de combiner le tout dans un test cosmologique géométrique pour déterminer les valeurs des paramètres cosmologiques Omega et Lambda. Les paramètres cosmologiques Omegaspan>et Lambdaspan>décrivent la géométrie globale de l'Univers. En faisant des hypothèses raisonnables sur la distribution spatiale et l'évolution des objets astrophysiques (galaxies, amas des galaxies, quasars), on peut déterminer les valeurs de ces paramètres qui sont cohérentes avec ces hypothèses. Les tests cosmologiques traditionnels ont besoin de ''chandelles standards'', objets dont les propriétés intrinsèques sont indépendantes des distances. De tels objets sont probablement fictifs. Néanmoins, certains de ces tests cosmologiques peuvent être adaptés si l'évolution individuelle, ou au moins l'évolution statistique d'une population d'objets est connue. La question de la nature de l'évolution des quasars a très vite été posée et des réponses ''phénoménologiques'' ont d'abord été données. Ces réponses ne faisaient que donner une forme mathématique à l'évolution mais n'expliquaient rien de la physique duphénomène. Les premières tentatives de construction d'un modèle physique, liées au processus d'accrétion sur un trou noir et à la théorie de la formation de l'Univers ont commencé à la fin des années 80. Depuis, des dizaines de modèles tentent d'expliquer les observations, qui sont les résultats de l'étude d'objets de plus en plus nombreux. Au cours de cette thèse, le test V/Vmax a été appliqué sur l'échantillon du Large Bright Quasar Survey en montrant 1) que l'échantillon était biaisé à cause des critères de sélection et 2) que la (simple) loi de Pure Evolution en Luminosité n'était pas une bonne approximation à tout

  1. Microstructure observations on butt joint composed of Nb3Sn CIC conductors

    NASA Astrophysics Data System (ADS)

    Obana, Tetsuhiro; Tokitani, Masayuki; Takahata, Kazuya; Kizu, Kaname; Murakami, Haruyuki

    2017-01-01

    To precisely evaluate a butt joint technology for the JT-60SA CS coils, microstructure observations on the butt joint composed of Nb3Sn CIC conductors were conducted using a FE-SEM. As a sample for the observations, the butt joint sample utilized in the joint resistance measurement was used. During the sample fabrication, the butt joint sample was heated up to about 920 K from room temperature for diffusion bonding after heat treatment for Nb3Sn production. Then, the sample was subjected to the cycles of electromagnetic force in the joint measurement. The observation results indicated that Nb3Sn strands and a copper sheet were butted properly at the interface of the butt joint. In addition, there were hairline cracks in the Nb3Sn layers of the strands near the interface. To investigate a cause of the crack initiation, the stresses generated in the butt joint under same conditions were analyzed using a simple model. As a result, the cracks would occur with an axial compressive stress generated by the butt joint fabrication.

  2. Novel coprocessed excipients composed of lactose, HPMC, and PVPP for tableting and its application.

    PubMed

    Wang, SongTao; Li, JinZhi; Lin, Xiao; Feng, Yi; Kou, Xiang; Babu, Sreehari; Panicucci, Riccardo

    2015-01-01

    New coprocessed excipients composed of α-lactose monohydrate (a filler), HPMC E3 (a binder), and PVPP (a superdisintegrant) were developed by spray drying in this study to improve the tableting properties of lactose. Factors affecting the properties of the coprocessed excipients were investigated by a 3 × 3 × 2 factorial design. These factors include lactose grade (90 M, 200 M, and 450 M), percentage of HPMC (3.5%, 7.0%, and 10.5%), and percentage of PVPP (0% and 3.5%). The results show that the compactability of the excipients could be significantly improved by increasing either the percentage of HPMC or the primary particle size of lactose. The addition of 3.5% PVPP had little effect on the compactability, but significantly improved the disintegration ability. The developed coprocessed excipients have much lower yield pressures and much higher working efficiency during tableting compared to the main raw material (α-lactose monohydrate). These improvements are mainly attributed to the addition of HPMC and the proximately 30% amorphous lactose formed during process. Both HPMC and amorphous lactose were homogeneously distributed on the surface of the secondary particles, maximizing their effect. Furthermore, the low hygroscopicity and high glass transition temperature of HPMC led to a high yield. The drug loading capacity of the newly coprocessed excipients is also excellent. In summary, the tri-component coprocessed excipients investigated are promising and worthy of further development.

  3. Designing a Composable Geometric Toolkit for Versatility in Applications to Simulation Development

    NASA Technical Reports Server (NTRS)

    Reed, Gregory S.; Campbell, Thomas

    2008-01-01

    Conceived and implemented through the development of probabilistic risk assessment simulations for Project Constellation, the Geometric Toolkit allows users to create, analyze, and visualize relationships between geometric shapes in three-space using the MATLAB computing environment. The key output of the toolkit is an analysis of how emanations from one "source" geometry (e.g., a leak in a pipe) will affect another "target" geometry (e.g., another heat-sensitive component). It can import computer-aided design (CAD) depictions of a system to be analyzed, allowing the user to reliably and easily represent components within the design and determine the relationships between them, ultimately supporting more technical or physics-based simulations that use the toolkit. We opted to develop a variety of modular, interconnecting software tools to extend the scope of the toolkit, providing the capability to support a range of applications. This concept of simulation composability allows specially-developed tools to be reused by assembling them in various combinations. As a result, the concepts described here and implemented in this toolkit have a wide range of applications outside the domain of risk assessment. To that end, the Geometric Toolkit has been evaluated for use in other unrelated applications due to the advantages provided by its underlying design.

  4. Non-Enzymatic Glucose Sensor Composed of Carbon-Coated Nano-Zinc Oxide

    PubMed Central

    Chung, Ren-Jei; Wang, An-Ni; Liao, Qing-Liang; Chuang, Kai-Yu

    2017-01-01

    Nowadays glucose detection is of great importance in the fields of biological, environmental, and clinical analyzes. In this research, we report a zinc oxide (ZnO) nanorod powder surface-coated with carbon material for non-enzymatic glucose sensor applications through a hydrothermal process and chemical vapor deposition method. A series of tests, including crystallinity analysis, microstructure observation, and electrochemical property investigations were carried out. For the cyclic voltammetric (CV) glucose detection, the low detection limit of 1 mM with a linear range from 0.1 mM to 10 mM was attained. The sensitivity was 2.97 μA/cm2mM, which is the most optimized ever reported. With such good analytical performance from a simple process, it is believed that the nanocomposites composed of ZnO nanorod powder surface-coated with carbon material are promising for the development of cost-effective non-enzymatic electrochemical glucose biosensors with high sensitivity. PMID:28336869

  5. Left-handed and right-handed metamaterials composed of split ring resonators and strip wires

    NASA Astrophysics Data System (ADS)

    Woodley, J. F.; Wheeler, M. S.; Mojahedi, M.

    2005-06-01

    The behavior of two structures composed of split ring resonators (SRRs) and strip wires (SWs) is examined through full wave simulations. It is shown that both structures exhibit a transmission peak in the region where the real parts of the electric permittivity and magnetic permeability are presumed to be negative, a property which is usually assumed to imply a negative index of refraction. However, an analysis of the dispersion characteristics and insertion phase of the two structures shows that the first structure, in which the SRRs and SWs are printed on opposite sides of a dielectric substrate, is a left-handed medium in the passband, whereas the second structure, in which SRRs and SWs are printed on the same side, is a right-handed medium in the passband. Hence the transmission magnitude alone does not provide sufficient evidence of a negative index of refraction. To determine the sign of the index correctly, the insertion phase for propagation through several lengths of the structure or calculations of dispersion diagrams are necessary. The impact of the unit cell size on the “handedness” of the structure is also examined.

  6. A genetic method for generating Drosophila eyes composed exclusively of mitotic clones of a single genotype.

    PubMed Central

    Stowers, R S; Schwarz, T L

    1999-01-01

    The genetic analysis of a gene at a late developmental stage can be impeded if the gene is required at an earlier developmental stage. The construction of mosaic animals, particularly in Drosophila, has been a means to overcome this obstacle. However, the phenotypic analysis of mitotic clones is often complicated because standard methods for generating mitotic clones render mosaic tissues that are a composite of both mutant and phenotypically normal cells. We describe here a genetic method (called EGUF/hid) that uses both the GAL4/UAS and FLP/FRT systems to overcome this limitation for the Drosophila eye by producing genetically mosaic flies that are otherwise heterozygous but in which the eye is composed exclusively of cells homozygous for one of the five major chromosome arms. These eyes are nearly wild type in size, morphology, and physiology. Applications of this genetic method include phenotypic analysis of existing mutations and F(1) genetic screens to identify as yet unknown genes involved in the biology of the fly eye. We illustrate the utility of the method by applying it to lethal mutations in the synaptic transmission genes synaptotagmin and syntaxin. PMID:10430588

  7. Moderately large vibrations of doubly curved shallow open shells composed of thick layers

    NASA Astrophysics Data System (ADS)

    Adam, Christoph

    2007-02-01

    This paper addresses nonlinear flexural vibrations of shallow shells composed of three thick layers with different shear flexibility, which are symmetrically arranged with respect to the middle surface. The considered shell structures of polygonal planform are hard hinged simply supported (i.e. all in-plane rotations and the bending moment vanish) with the edges fully restraint against displacements in any direction. The kinematic field equations are formulated by layerwise application of a first-order shear deformation theory. A modification of Berger's theory is employed to model the nonlinear characteristics of the structural response. The continuity of the transverse shear stress across the interfaces is specified according to Hooke's law, and subsequently the equations of motion of this higher order problem can be derived in analogy to a homogeneous single-layer shear deformable shallow shell. Numerical results of rectangular shallow shells in nonlinear steady-state vibration are presented for various ratios of shell rise to thickness, and non-dimensional load amplitude.

  8. Combining phase images from array coils using a short echo time reference scan (COMPOSER)

    PubMed Central

    Dymerska, Barbara; Bogner, Wolfgang; Barth, Markus; Zaric, Olgica; Goluch, Sigrun; Grabner, Günther; Deligianni, Xeni; Bieri, Oliver; Trattnig, Siegfried

    2015-01-01

    Purpose To develop a simple method for combining phase images from multichannel coils that does not require a reference coil and does not entail phase unwrapping, fitting or iterative procedures. Theory and Methods At very short echo time, the phase measured with each coil of an array approximates to the phase offset to which the image from that coil is subject. Subtracting this information from the phase of the scan of interest matches the phases from the coils, allowing them to be combined. The effectiveness of this approach is quantified in the brain, calf and breast with coils of diverse designs. Results The quality of phase matching between coil elements was close to 100% with all coils assessed even in regions of low signal. This method of phase combination was similar in effectiveness to the Roemer method (which needs a reference coil) and was superior to the rival reference‐coil‐free approaches tested. Conclusion The proposed approach—COMbining Phase data using a Short Echo‐time Reference scan (COMPOSER)—is a simple and effective approach to reconstructing phase images from multichannel coils. It requires little additional scan time, is compatible with parallel imaging and is applicable to all coils, independent of configuration. Magn Reson Med 77:318–327, 2017. © 2015 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine PMID:26712454

  9. General formulations for predicting longevity of submerged superhydrophobic surfaces composed of pores or posts.

    PubMed

    Hemeda, A A; Tafreshi, H Vahedi

    2014-09-02

    Superhydrophobicity can arise from the ability of a submerged rough hydrophobic surface to trap air in its surface pores, and thereby reduce the contact area between the water and the frictional solid walls. A submerged surface can only remain superhydrophobic (SHP) as long as it retains the air in its pores. SHP surfaces have a short underwater life, and their longevity depends strongly on the hydrostatic pressure at which they operate. In this work, a comprehensive mathematical framework is developed to predict the mechanical stability and the longevity of submerged SHP surfaces with arbitrary pore or post geometries. We start by deriving an integro-partial differential equation for the 3-D shape of the air-water interface, and use this information to predict the rate of dissolution of the entrapped air into the ambient water under different hydrostatic pressures. For the special case of circular pores, the above integro-partial differential equation is reduced to easy-to-solve ordinary differential equations. In addition, approximate nonlinear algebraic solutions are also obtained for surfaces with circular pores or posts. The effects of geometrical parameters and hydrostatic conditions on surface stability and longevity are discussed in detail. Moreover, a simple equivalent pore diameter method is developed for SHP surfaces composed of posts with ordered or random configuration--an otherwise complicated task requiring the solution of an integro-partial differential equation.

  10. Preparation and characteristics of hybrid scaffolds composed of beta-chitin and collagen.

    PubMed

    Lee, Sang Bong; Kim, Yong Han; Chong, Moo Sang; Lee, Young Moo

    2004-05-01

    Hybrid scaffolds composed of beta-chitin and collagen were prepared by combining salt-leaching and freeze-drying methods. The chitin scaffold used as a framework was easily formed into desired shapes with a uniformly distributed and interconnected pore structure with average pore size of 260-330 microm. The mechanical strength and the rate of biodegradation increased with the porosity, which could be modulated by the salt concentration. In addition, atelocollagen solution was introduced into the macropores of the chitin scaffold to improve cell attachment. Web-like collagen fibers fabricated between pores of chitin were produced by a 0.1 wt% collagen solution, whereas a 0.5 wt% collagen solution only coated the surface of the chitin scaffold. After 3 days of culture, fibroblasts cultured in collagen-coated scaffolds were attached at the place where the collagen was fabricated, whereas cells did not attach and aggregate on the scaffold of chitin alone. After 14 days, the fibroblasts showed a good affinity to and proliferation on all collagen-coated chitins.

  11. Delivery of rosiglitazone from an injectable triple interpenetrating network hydrogel composed of naturally derived materials.

    PubMed

    Zhang, Hanwei; Qadeer, Aisha; Mynarcik, Dennis; Chen, Weiliam

    2011-01-01

    An in situ gelable and biodegradable triple-interpenetrating network (3XN) hydrogel, completely devoid of potentially cytotoxic extraneous small molecule crosslinkers, is formulated from partially oxidized dextran (Odex), teleostean and N-carboxyethyl chitosan (CEC). Both the rheological profile and mechanical strength of the 3XN hydrogel approximate the combined characteristics of the three individual hydrogels composed of the binary partial formulations (i.e., Odex/CEC, Odex/teleostean, and CEC/teleostean). The 3XN hydrogel is considerably more resistant to fibroblast-mediated degradation compared to each partial formulation in cell culture models; this is attributable to the interpenetrating triple-network structure. The presence of teleostean in the 3XN hydrogel imparts cell affinity, constituting an environment amenable to fibroblast growth. in vivo subdermal injection into mouse model shows that the 3XN hydrogel does not induce extensive inflammatory response nor is there any evidence of tissue necrosis, further confirming the non-cytotoxicity of the hydrogel and its degradation byproducts. Importantly, the capability of the 3XN hydrogel to serve as a sustained drug delivery vehicle is confirmed using rosiglitazone as a model drug. The presence of rosiglitazone profoundly changes the cell/tissue interactions with the subdermally injected 3XN hydrogel. Rosiglitazone suppresses both the inflammatory response and tissue repair in a dose-dependent manner and considerably moderated the hydrogel degradation.

  12. Magnetic memory in a ceramic YBCO superconductor composed of sub-micron-size grains

    NASA Astrophysics Data System (ADS)

    Deguchi, Hiroyuki; Ashida, Takuya; Syudo, Mitsuhiro; Mito, Masaki; Takagi, Seishi; Hagiwara, Makoto; Koyama, Kuniyuki

    2013-06-01

    The ceramic YBa2Cu4O8 (YBCO) composed of sub-micron-size grains is considered as a random Josephson-coupled network of 0 and π junctions and shows successive phase transitions. The first transition occurs inside each grain at T c1 = 81 K, and the second transition occurs among the grains at T c2 = 47 K. A magnetic glass behavior similar to those of spin-glasses is observed at temperatures below T c2. The memory phenomena are investigated by recording the zero-fieldcooled and thermoremanent magnetizations measured on heating after the cooling process with a halt at T s = 41 K. Memory effects of the halt are imprinted in the system when the sample is re-heated. In the case without a field switch at T s , the influence of the halt is confined to a narrow temperature region near T s whereas the memory effect of the halt employing a field switch is extended over a wide temperature region below T s . The results suggest that chiral-glass ordering occurs at T c2 in the ceramic YBCO.

  13. Conductance of a single flexible molecular wire composed of alternating donor and acceptor units

    PubMed Central

    Nacci, Christophe; Ample, Francisco; Bleger, David; Hecht, Stefan; Joachim, Christian; Grill, Leonhard

    2015-01-01

    Molecular-scale electronics is mainly concerned by understanding charge transport through individual molecules. A key issue here is the charge transport capability through a single—typically linear—molecule, characterized by the current decay with increasing length. To improve the conductance of individual polymers, molecular design often either involves the use of rigid ribbon/ladder-type structures, thereby sacrificing for flexibility of the molecular wire, or a zero band gap, typically associated with chemical instability. Here we show that a conjugated polymer composed of alternating donor and acceptor repeat units, synthesized directly by an on-surface polymerization, exhibits a very high conductance while maintaining both its flexible structure and a finite band gap. Importantly, electronic delocalization along the wire does not seem to be necessary as proven by spatial mapping of the electronic states along individual molecular wires. Our approach should facilitate the realization of flexible ‘soft' molecular-scale circuitry, for example, on bendable substrates. PMID:26145188

  14. Optical Properties of Internally Mixed Aerosol Particles Composed of Dicarboxylic Acids and Ammonium Sulfate

    NASA Astrophysics Data System (ADS)

    Freedman, Miriam A.; Hasenkopf, Christa A.; Beaver, Melinda R.; Tolbert, Margaret A.

    2009-10-01

    We have investigated the optical properties of internally mixed aerosol particles composed of dicarboxylic acids and ammonium sulfate using cavity ring-down aerosol extinction spectroscopy at a wavelength of 532 nm. The real refractive indices of these nonabsorbing species were retrieved from the extinction and concentration of the particles using Mie scattering theory. We obtain refractive indices for pure ammonium sulfate and pure dicarboxylic acids that are consistent with literature values, where they exist, to within experimental error. For mixed particles, however, our data deviates significantly from a volume-weighted average of the pure components. Surprisingly, the real refractive indices of internal mixtures of succinic acid and ammonium sulfate are higher than either of the pure components at the highest organic weight fractions. For binary internal mixtures of oxalic or adipic acid with ammonium sulfate, the real refractive indices of the mixtures are approximately the same as ammonium sulfate for all organic weight fractions. Various optical mixing rules for homogeneous and slightly heterogeneous systems fail to explain the experimental real refractive indices. It is likely that complex particle morphologies are responsible for the observed behavior of the mixed particles. Implications of our results for atmospheric modeling and aerosol structure are discussed.

  15. Domestic sewage treatment in a pilot system composed of UASB and SBR reactors.

    PubMed

    Torres, P; Foresti, E

    2001-01-01

    The results obtained from the operation of a treatment system composed of an anaerobic (up-flow sludge blanket-UASB) reactor followed by an aerobic (sequencing batch-SBR) reactor treating domestic sewage are presented and discussed. The pilot plant was monitored during 6 months, aiming to obtain performance data on organic matter, nitrogen and phosphate removal under different operating conditions. The UASB reactor was operated at a constant hydraulic detention time (0) of 6 h while the SBR performance was monitored in four different duration cycles (24, 12, 6 and 4 h) corresponding to aeration times (AT) of 22, 10, 4 and 2 h, respectively. COD and TSS overall removal efficiencies (Eo) up to 91% and 84%, respectively, were achieved independently on the aeration time applied to the SBR. In respect to nitrification and phosphate removal, AT was found to be a determining operating parameter. TKN removal of approximately 90% was achieved for AT equal to or higher than 10 h; complete nitrification occurred for AT higher than 4 h; significant phosphate removal (72%) occurred only at the AT of 2 h. It was not possible to achieve simultaneous efficient removal of nitrogen and phosphate, under the operating conditions imposed on the treatment system.

  16. Nanostructured CuS networks composed of interconnected nanoparticles for asymmetric supercapacitors.

    PubMed

    Fu, Wenbin; Han, Weihua; Zha, Heming; Mei, Junfeng; Li, Yunxia; Zhang, Zemin; Xie, Erqing

    2016-09-21

    Nanostructured metal sulfides with excellent electrochemical activity and electrical conductivity are particularly promising for applications in high-performance energy storage devices. Here, we report on the facile synthesis of nanostructured CuS networks composed of interconnected nanoparticles as novel battery-type materials for asymmetric supercapacitors. We find that the CuS networks exhibit a high specific capacity of 49.8 mA g(-1) at a current density of 1 A g(-1), good rate capability and cycle stability. The superior performance could be attributed to the interconnected nanoparticles of CuS networks, which can facilitate electrolyte diffusion and provide fast electron pathways. Furthermore, an aqueous asymmetric supercapacitor has been assembled by using the CuS networks as the positive electrode and activated carbon as the negative electrode. The assembled device can work at a high operating voltage of 1.6 V and show a maximum energy density of 17.7 W h kg(-1) at a power density of 504 W kg(-1). This study indicates that the CuS networks have great potential for supercapacitor applications.

  17. A biomaterial composed of collagen and solubilized elastin enhances angiogenesis and elastic fiber formation without calcification.

    PubMed

    Daamen, Willeke F; Nillesen, Suzan T M; Wismans, Ronnie G; Reinhardt, Dieter P; Hafmans, Theo; Veerkamp, Jacques H; van Kuppevelt, Toin H

    2008-03-01

    Elastin is the prime protein in elastic tissues that contributes to elasticity of, for example, lung, aorta, and skin. Upon injury, elastic fibers are not readily replaced, which hampers tissue regeneration. Incorporation of solubilized elastin (hydrolyzed insoluble elastin fibers or elastin peptides) in biomaterials may improve regeneration, because solubilized elastin is able to promote proliferation as well as elastin synthesis. Porous biomaterials composed of highly purified collagen without and without elastin fibers or solubilized elastin were prepared by freezing and lyophilization. Solubilized elastin formed spherical structures that were incorporated in the collagenous part of the scaffolds and that persisted after chemical crosslinking of the scaffolds. Crosslinked scaffolds were subcutaneously implanted in young Sprague Dawley rats. Collagen-solubilized elastin and collagen scaffolds showed no calcification in this sensitive calcification model, in contrast to scaffolds containing elastin fibers. Collagen-solubilized elastin scaffolds also induced angiogenesis, as revealed by type IV collagen staining, and promoted elastic fiber synthesis, as shown with antibodies against rat elastin and fibrillin-1. It is concluded that scaffolds produced from collagen and solubilized elastin present a non-calcifying biomaterial with a capacity for soft-tissue regeneration, especially in relation to elastic fiber synthesis.

  18. Characterization of planar biomimetic lipid films composed of phosphatidylethanolamines and phosphatidylglycerols from Escherichia coli.

    PubMed

    Konarzewska, Dorota; Juhaniewicz, Joanna; Güzeloğlu, Alişan; Sęk, Sławomir

    2017-03-01

    We have characterized planar lipid films composed of phosphatidylethanolamines (PE) and phosphatidylglycerols (PG) from E. coli bacteria. The nature of the interactions and miscibility of PE and PG components within mixed lipid films was evaluated based on surface pressure measurements and Brewster angle microscopy imaging at the air-water interface. We have found that PE and PG components show tendency to form separated domains at surface pressures relevant for biological membranes. Further, we have directly compared mechanisms of formation of supported lipid bilayers either on mica or Au(111) by spreading of small unilamellar vesicles. The bilayer formation was monitored by in situ atomic force microscopy imaging. The pathways of the vesicles spreading on each substrate are substantially different and the buildup of the bilayer on Au(111) occurs through complex multistep mechanism. The morphology and nanomechanical properties of the resulting PE/PG bilayers were thoroughly compared. We have found that the interactions between lipids and supporting substrate significantly affect molecular organization within the films since the bilayer on Au(111) is uniform in terms of the topography, while the same lipid composition on mica results in formation of distinct gel and liquid disordered domains. Different molecular organization affects also nanomechanical properties of lipid films. The latter were expressed in terms of Young's moduli and bending stiffness.

  19. Blending materials composed of boron, nitrogen and carbon to transform approaches to liquid hydrogen stores

    SciTech Connect

    Whittemore, Sean M.; Bowden, Mark; Karkamkar, Abhijeet; Parab, Kshitij; Neiner, Doinita; Autrey, Tom; Ishibashi, Jacob S. A.; Chen, Gang; Liu, Shih-Yuan; Dixon, David A.

    2015-12-02

    Energy storage remains a key challenge for the advancement of fuel cell applications. Because of this, hydrogen has garnered much research attention for its potential as an energy carrier. This can be attributed to its abundance from non-petroleum sources, and its energy conversion efficiency. Our group, among others, has been studying the use of ammonia borane as a chemical hydrogen storage material for the past several years. Ammonia borane (AB, NH3BH3), a solid state complex composed of the light weight main group elements of nitrogen and boron, is isoelectronic with ethane and as such is an attractive hydrogen storage material with a high gravimetric capacity of H2 (19.6 wt%). However, the widespread use of AB as a chemical hydrogen storage material has been stalled by some undesirable properties and reactivity. Most notably, AB is a solid and this presents compatibility issues with the existing liquid fuel infrastructure. The thermal release of H2 from AB also results in the formation of volatile impurities (borazine and ammonia) that are detrimental to operation of the fuel cell. Additionally, the major products in the spent fuel are polyborazylene and amine borane oligomers that present challenges in regenerating AB. This research was funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy. The Pacific Northwest National Laboratory is operated by Battelle for DOE.

  20. Beyond the Shannon–Khinchin formulation: The composability axiom and the universal-group entropy

    SciTech Connect

    Tempesta, Piergiulio

    2016-02-15

    The notion of entropy is ubiquitous both in natural and social sciences. In the last two decades, a considerable effort has been devoted to the study of new entropic forms, which generalize the standard Boltzmann–Gibbs (BG) entropy and could be applicable in thermodynamics, quantum mechanics and information theory. In Khinchin (1957), by extending previous ideas of Shannon (1948) and Shannon and Weaver (1949), Khinchin proposed a characterization of the BG entropy, based on four requirements, nowadays known as the Shannon–Khinchin (SK) axioms. The purpose of this paper is twofold. First, we show that there exists an intrinsic group-theoretical structure behind the notion of entropy. It comes from the requirement of composability of an entropy with respect to the union of two statistically independent systems, that we propose in an axiomatic formulation. Second, we show that there exists a simple universal family of trace-form entropies. This class contains many well known examples of entropies and infinitely many new ones, a priori multi-parametric. Due to its specific relation with Lazard’s universal formal group of algebraic topology, the new general entropy introduced in this work will be called the universal-group entropy. A new example of multi-parametric entropy is explicitly constructed.

  1. Characterization of a liver organoid tissue composed of hepatocytes and fibroblasts in dense collagen fibrils.

    PubMed

    Tamai, Miho; Adachi, Eijiro; Tagawa, Yoh-ichi

    2013-11-01

    The adult liver is wrapped in a connective tissue sheet called the liver capsule, which consists of collagen fibrils and fibroblasts. In this study, we set out to construct a liver organoid tissue that would be comparable to the endogenous liver, using a bioreactor. In vitro liver organoid tissue was generated by combining collagen fibrils, fibroblasts, and primary murine hepatocytes or Hep G2 on a mesh of poly-lactic acid fabric using a bioreactor. Then, the suitability of this liver organoid tissue for transplantation was tested by implanting the constructs into partially hepatectomized BALB/cA-nu/nu mice. As determined by using scanning and transmission electron microscopes, the liver organoid tissues were composed of densely packed collagen fibrils with fibroblasts and aggregates of oval or spherical hepatocytes. Angiogenesis was induced after the transplantation, and blood vessels connected the liver organoid tissue with the surrounding tissue. Thus, a novel approach was applied to generate transplantable liver organoid tissue within a condensed collagen fibril matrix. These results suggested that a dense collagen network populated with fibroblasts can hold a layer of concentrated hepatocytes, providing a three-dimensional microenvrionment suitable for the reestablishment of cell-cell and cell-extracellular matrix (ECM) interactions, and resulting in the maintenance of their liver-specific functions. This liver organoid tissue may be useful for the study of intrahepatic functions of various cells, cytokines, and ECMs, and may fulfill the fundamental requirements of a donor tissue.

  2. Pose control of the chain composed of magnetic particles using external uniform and gradient magnetic fields

    NASA Astrophysics Data System (ADS)

    Zhou, J. F.; Shao, C. L.; Gu, B. Q.

    2016-01-01

    Magnetic particles (MPs) are known to respond to a magnetic field and can be moved by magnetic force, which make them good carriers in bioengineering and pharmaceutical engineering. In this paper, a pose control method for the straight chain composed of MPs is proposed, and the chain with one pose can be moved to another position with another pose using alternately employed uniform and gradient magnetic fields. Based on computer simulations, it is revealed that in the uniform magnetic field, the MPs form a straight chain with the same separation space along the field lines, and once the uniform magnetic field rotates, the chain also rotates with the field. In the gradient magnetic field, the MPs move toward the higher field so that the translation of the chain can be realized. The simulation results indicate that while the uniform magnetic field is rotating, there exists certain hysteresis between the chain and the field, and the chain is not straight anymore. So the uniform magnetic field should rest at the target angle for a period to make the chain fully relax to be straight. For nanoMP, its magnetic moment directly determines the gradient magnetic force which is much smaller than the dipole-dipole force among MPs. Therefore, the translation of the chain is much more time-consuming than rotation. To enlarge the translational velocity, it is suggested to increase the size of MPs or the magnetic field gradient.

  3. Treatment of ingrown nail with a special device composed of shape-memory alloy.

    PubMed

    Park, Se-Won; Park, Ji-Ho; Lee, Jong-Hee; Lee, Dong-Youn; Lee, Joo-Heung; Yang, Jun-Mo

    2014-04-01

    Ingrown nail is a common nail problem resulting in pain and disability in daily life. Recently, a new treatment modality for an ingrown nail was reported that used a device composed of shape-memory alloy, K-D. The aim of the present study was to determine the efficacy, recurrence rate and complications of K-D. Between June 2010 and September 2012, 24 patients (31 nails) underwent treatment of symptomatic incurved nails with a K-D. Patients were evaluated at pretreatment and during every visit. The mean age of the patients involved was 43.4 years. The mean period of follow up was 161 days. The mean maintenance period was 41 days. The right first toenail was the most common site. Almost ingrown nails healed and the nail deformity was corrected after the procedure. Among the 31 nails, seven of the ingrown nails recurred during follow up (22.6% recurrence rate). The recurrence rate of the patients with stage 1, 2 and 3 ingrown nails was 22.2%, 33.3% and 14.2%, respectively. The majority of patients were very satisfied. There were no side-effects in most patients except loss of nail in one patient. K-D has some advantages such as simple application steps, no deformity after the procedure, high patient satisfaction and obvious effect compared to other non-invasive and invasive methods.

  4. Beyond the Shannon-Khinchin formulation: The composability axiom and the universal-group entropy

    NASA Astrophysics Data System (ADS)

    Tempesta, Piergiulio

    2016-02-01

    The notion of entropy is ubiquitous both in natural and social sciences. In the last two decades, a considerable effort has been devoted to the study of new entropic forms, which generalize the standard Boltzmann-Gibbs (BG) entropy and could be applicable in thermodynamics, quantum mechanics and information theory. In Khinchin (1957), by extending previous ideas of Shannon (1948) and Shannon and Weaver (1949), Khinchin proposed a characterization of the BG entropy, based on four requirements, nowadays known as the Shannon-Khinchin (SK) axioms. The purpose of this paper is twofold. First, we show that there exists an intrinsic group-theoretical structure behind the notion of entropy. It comes from the requirement of composability of an entropy with respect to the union of two statistically independent systems, that we propose in an axiomatic formulation. Second, we show that there exists a simple universal family of trace-form entropies. This class contains many well known examples of entropies and infinitely many new ones, a priori multi-parametric. Due to its specific relation with Lazard's universal formal group of algebraic topology, the new general entropy introduced in this work will be called the universal-group entropy. A new example of multi-parametric entropy is explicitly constructed.

  5. Phase coexistence in films composed of DLPC and DPPC: a comparison between different model membrane systems.

    PubMed

    Mangiarotti, Agustín; Caruso, Benjamín; Wilke, Natalia

    2014-07-01

    For the biophysical study of membranes, a variety of model systems have been used to measure the different parameters and to extract general principles concerning processes that may occur in cellular membranes. However, there are very few reports in which the results obtained with the different models have been compared. In this investigation, we quantitatively compared the phase coexistence in Langmuir monolayers, freestanding bilayers and supported films composed of a lipid mixture of DLPC and DPPC. Two-phase segregation was observed in most of the systems for a wide range of lipid proportions using fluorescence microscopy. The lipid composition of the coexisting phases was determined and the distribution coefficient of the fluorescent probe in each phase was quantified, in order to explore their thermodynamic properties. The comparison between systems was carried out at 30mN/m, since it is accepted that at this or higher lateral pressures, the mean molecular area in bilayers is equivalent to that observed in monolayers. Our study showed that while Langmuir monolayers and giant unilamellar vesicles had a similar phase behavior, supported films showed a different composition of the phases with the distribution coefficient of the fluorescent probe being close to unity. Our results suggest that, in supported membranes, the presence of the rigid substrate may have led to a stiffening of the liquid-expanded phase due to a loss in the degrees of freedom of the lipids as a consequence of the proximity of the solid material.

  6. 2. Photocopied 1972 from Ecole imperiale des ponts et chaussees, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Photocopied 1972 from Ecole imperiale des ponts et chaussees, Collection de Dessins Distribues aus eleves, (n.d. and no place), ORIGINAL FINK TRUSS BRIDGE, 1852. - Baltimore & Ohio Railroad, Fairmont Bridge, Spanning Monongahela River, Fairmont, Marion County, WV

  7. Le syndrome des enfants battus: aspects cliniques et radiologiques

    PubMed Central

    Jlalia, Zied; Znaigui, Talel; Smida, Mahmoud

    2016-01-01

    La maltraitance physique des enfants ou le syndrome des enfants battus est responsable de plus de 75.000 décès par an en France. Ce problème de santé publique reste sous diagnostiqué en Tunisie et dans le monde. Le chemin a été laborieux pour la reconnaissance du syndrome des enfants battus dans certaines sociétés même occidentales. Nous avons voulus exposer ce problème aux praticiens afin qu'il soit mieux diagnostiqué et pris en charge. La maltraitance physique des enfants est appelée à tort syndrome de Silverman qui ne regroupe en fait que les lésions squelettiques chez ces enfants tels que les fractures. Mots clés: Fracture, maltraitance, enfant, neuro-radiologie PMID:27642408

  8. Discovery and Classification of DES15S2kqw

    NASA Astrophysics Data System (ADS)

    Kasai, E.; Bassett, B.; Crawford, S.; Kniazev, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.

    2015-10-01

    We report optical spectroscopy of DES15S2kqw discovered by the Dark Energy Survey. The spectrum (380-820nm) was obtained using the Robert Stobie Spectrograph (RSS) on the South African Large Telescope (SALT).

  9. RadNet Air Data From Des Moines, IA

    EPA Pesticide Factsheets

    This page presents radiation air monitoring and air filter analysis data for Des Moines, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

  10. Quantification des besoins en intrants antipaludiques: contribution à l'actualisation des hypothèses pour la quantification des intrants de prise en charge des cas de paludisme grave en République Démocratique du Congo

    PubMed Central

    Likwela, Joris Losimba; Otokoye, John Otshudiema

    2015-01-01

    Les formes graves de paludisme à Plasmodium falciparum sont une cause majeure de décès des enfants de moins de 5 ans en Afrique Sub-saharienne. Un traitement rapide dépend de la disponibilité de médicaments appropriés au niveau des points de prestation de service. La fréquence des ruptures de stock des commodités antipaludiques, en particuliers celles utilisées pour le paludisme grave, avait nécessité une mise à jour des hypothèses de quantification. Les données issues de la collecte de routine du PNLP de 2007 à 2012 ont été comparées à celles rapportés par d'autres pays africains et utilisées pour orienter les discussions au cours d'un atelier organisé par le PNLP et ses partenaires techniques et financiers afin de dégager un consensus national. La proportion des cas de paludisme rapportés comme grave en RDC est resté autour d'une médiane de 7% avec un domaine de variation de 6 à 9%. Hormis la proportion rapportée au Kenya (2%), les pays africains ont rapporté une proportion de cas grave variant entre 5 et 7%. Il apparaît que la proportion de 1% précédemment utilisée pour la quantification en RDC a été sous-estimée dans le contexte de la gestion des cas graves sur terrain. Un consensus s'est dégagé autour de la proportion de 5% étant entendu que des efforts de renforcement des capacités seraient déployés afin d'améliorer le diagnostic au niveau des points de prestation des services. PMID:26213595

  11. Cout de Maintenance et Duree de Vie des Turbomoteurs

    DTIC Science & Technology

    2003-02-01

    UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP014136 TITLE: Cout de Maintenance et Duree de Vie des Turbomoteurs...termes op~rationnels et de gestion de flotte moteurs en service, il est cofiteux. Communication prisentge lors dit sYmiposium RTO A UTsur (f Les...macanismes vieillissants et le contrrle: Partie B - Le suivi et la gestion des turbomoteurs en vue Ai prolongement de leur durae de vie et de la

  12. Fehlertoleranzanalyse des FlexRay Startup-Prozesses

    NASA Astrophysics Data System (ADS)

    Bünte, Sven; Milbredt, Paul

    Die PlexfiRay-Prozeduren Wakeup und Startup sollen eine konsistent-synchrone Kommunikation bezüglich eines TDMA verwandten Verfuhrens herstellen. Beide Algorithmen werden in dieser Arbeit ubstrukt modelliert und mit Hilfe des Model Checkers SPIN bezüglich Terminierung analysiert. Die Ergebnisse zeigen, dass in bestimmten Fehlerszenarios die Verwendung von Central Bus Guardians, die Clusterkonfiguration und das Verhalten des Hosts darüber entscheiden, ob Fehlertoleranz und Laufzeitbeschränkungen garantiert werden können.

  13. The Basic Physical Mechanism for Disconnection Events(DEs)

    NASA Astrophysics Data System (ADS)

    Brandt, J. C.

    2004-11-01

    Disconnection Events (DEs) are arguably the most dramatic phenomena in cometary physics. The entire plasma tail disconnects from the head, and image sequences have been available for approximately one century. Many details were known to Barnard (1899, 1908, 1920) and his contemporaries. Modern DE studies began with the rediscovery of the phenomena by Niedner & Brandt (1978) and their proposal that the physical mechanism was the severing of the magnetic field lines by magnetic reconnection at crossings of the heliospheric current sheet (HCS). While many areas of investigation-direct spacecraft observations (Niedner & Schwingenschuh 1987; Verigin et al. 1987; Kirsch et al. 1989); associations of DEs with solar-wind features (Niedner & Brandt 1979; Yi et al. 1994; Brandt et al. 1999); and magnetohydrodynamic (MHD) simulations of DEs (Yi et al. 1996)-strongly supported this physical mechanism, areas of concern or disagreement remained (e.g., Farnham & Meech 1994; Wegmann 1995, 1998, 2000). Recent results seem to resolve the problems in all areas. The associations of DEs with solar-wind features have been extensively reinvestigated (Niedner et al. 2005). In particular, many high-speed streams are not associated with the HCS (as many as 40%) and these high-speed streams are definitely not associated with DEs. Finally, Konz et al. (2004) have reproduced DEs at crossings of the HCS using plasma-neutral gas simulations with anomalous resistivity. The new evidence strongly confirms the sunward, magnetic reconnection physical mechanism proposed by Niedner & Brandt (1978).

  14. Identification et prise en charge des femmes ayant des antécédents familiaux de cancer du sein

    PubMed Central

    Heisey, Ruth; Carroll, June C.

    2016-01-01

    Résumé Objectif Résumer les meilleures données portant sur les stratégies d’identification et de prise en charge des femmes qui présentent des antécédents familiaux de cancer du sein. Sources d’information Une recherche a été effectuée sur PubMed à l’aide des mots-clés anglais suivants : breast cancer, guidelines, risk, family history, management et magnetic resonance imaging screening, entre 2000 et 2016. La plupart des données sont de niveau II. Message principal Une bonne anamnèse familiale est essentielle lors de l’évaluation du risque de cancer du sein afin d’identifier les femmes qui sont candidates à une recommandation en counseling génétique pour un éventuel test génétique. On peut sauver des vies en offrant aux femmes porteuses d’une mutation au gène BRCA des interventions chirurgicales de réduction des risques (mastectomie bilatérale prophylactique, salpingo-ovariectomie bilatérale). Il faut encourager toutes les femmes qui présentent des antécédents familiaux de cancer du sein à demeurer actives et à limiter leur consommation d’alcool à moins de 1 verre par jour; certaines femmes sont admissibles à la chimioprévention. Il faut offrir aux femmes dont le risque à vie de cancer du sein est de 20 à 25 % ou plus un dépistage poussé par imagerie par résonance magnétique en plus d’une mammographie. Conclusion Une vie saine et la chimioprévention (chez les candidates) pourraient réduire l’incidence du cancer du sein; le dépistage poussé pourrait entraîner une détection plus précoce. Le fait d’aiguiller des femmes porteuses d’une mutation au BRCA vers la chirurgie de réduction des risques sauve des vies. PMID:27737991

  15. [Le leadership en santé et l'éthique de la gestion des attentes des soignants et des patients].

    PubMed

    Browne, Alister

    2016-03-01

    Les dispensateurs de soins et les patients sont souvent déçus du niveau de soins que les hôpitaux publics peuvent prodiguer. La solution consiste à réduire les attentes. Les dispensateurs devraient être amenés à considérer que leur obligation consiste à prodiguer les meilleurs soins en fonction des ressources. Le public devrait être bien informé des services que les hôpitaux de soins actifs peuvent ou non lui offrir et participer aux prises de décision. Les leaders en santé peuvent jouer des rôles novateurs à cet égard.

  16. Characteristics of wasteform composing of phosphate and silicate to immobilize radioactive waste salts.

    PubMed

    Park, Hwan-Seo; Cho, In-Hak; Eun, Hee Chul; Kim, In-Tae; Cho, Yong Zun; Lee, Han-Soo

    2011-03-01

    In the radioactive waste management, metal chloride wastes from a pyrochemical process is one of problematic wastes not directly applicable to a conventional solidification process. Different from a use of minerals or a specific phosphate glass for immobilizing radioactive waste salts, our research group applied an inorganic composite, SAP (SiO(2)-Al(2)O(3)-P(2)O(5)), to stabilize them by dechlorination. From this method, a unique wasteform composing of phosphate and silicate could be fabricated. This study described the characteristic of the wasteform on the morphology, chemical durability, and some physical properties. The wasteform has a unique "domain-matrix" structure which would be attributed to the incompatibility between silicate and phosphate glass. At higher amounts of chemical binder, "P-rich phase encapsulated by Si-rich phase" was a dominant morphology, but it was changed to be Si-rich phase encapsulated by P-rich phase at a lower amount of binder. The domain and subdomain size in the wasteform was about 0.5-2 μm and hundreds of nm, respectively. The chemical durability of wasteform was confirmed by various leaching test methods (PCT-A, ISO dynamic leaching test, and MCC-1). From the leaching tests, it was found that the P-rich phase had ten times lower leach-resistance than the Si-rich phase. The leach rates of Cs and Sr in the wasteform were about 10(-3)g/m(2)· day, and the leached fractions of them were about 0.04% and 0.06% at 357 days, respectively. Using this method, we could stabilize and solidify the waste salt to form a monolithic wasteform with good leach-resistance. Also, the decrease of waste volume by the dechlorination approach would be beneficial in the final disposal cost, compared with the present immobilization methods for waste salt.

  17. Histological and genetic evidence for a variant of superficial spreading melanoma composed predominantly of large nests.

    PubMed

    Kutzner, Heinz; Metzler, Gisela; Argenyi, Zsolt; Requena, Luis; Palmedo, Gabriele; Mentzel, Thomas; Rütten, Arno; Hantschke, Markus; Paredes, Bruno E; Schärer, Leo; Hesse, Benedikt; El-Shabrawi-Caelen, Laila; Shabrawi-Caelen, Leila El; Fried, Isabella; Kerl, Helmut; Lorenzo, Cerroni; Murali, Rajmohan; Wiesner, Thomas

    2012-06-01

    Cutaneous melanomas are characterized by a range of histological appearances, and several morphological variants have been described. In this study, we report a variant of superficial spreading melanoma that is characterized by large, irregular junctional melanocytic nests. The junctional nests varied in shape and size, showed focal tendency to confluence, and were often surrounded by a cuff of epidermal keratinocytes. The melanocytes comprising the nests showed variable cytological atypia. In most of the cases, scant intraepidermal or junctional single melanocytes were seen, and other well-documented diagnostic criteria for melanoma were lacking, and as a result, histological recognition of these tumors as melanoma was difficult. Some cases were associated with an invasive dermal component or showed evidence of sun damage. To provide supporting evidence for malignancy, we analyzed these tumors for genomic aberrations. Using array comparative genomic hybridization (aCGH), we identified multiple genomic aberrations in all analyzed cases. A similar pattern of genomic aberrations was seen in a control group of bona fide superficial spreading melanomas, suggesting that these 'melanomas composed exclusively or predominantly of large nests' are indeed variants of superficial spreading melanoma. Fluorescence in-situ hybridization (FISH) was positive in 40% of the cases. However, using aCGH, the FISH-negative cases showed multiple genomic aberrations in regions that are not covered by FISH. The low sensitivity of the FISH test can be explained by the fact that FISH only evaluates four genomic loci for aberrations, whereas aCGH surveys the entire genome. In summary, we present histological and molecular genetic evidence for a morphological variant of superficial spreading melanoma. Awareness of the histological features will aid in their correct diagnosis as melanoma, and in difficult cases, judicious application of ancillary tests such as aCGH (rather than FISH) will

  18. Dispersion of Vesicles Composed of Industrially Produced Alkyl (Oligo) Glucoside Using Diol-Boron Complexation.

    PubMed

    Aikawa, Tatsuo; Asano, Yuuka; Kondo, Takeshi; Yuasa, Makoto

    2016-07-01

    Alkyl (oligo)glucosides (AOG) are known to be environmentally compatible amphiphiles whose commercial applicability should be broadened. The present paper describes the preparation of molecular assemblies of industrially produced AOG, which is a mixture composed of different length of alkyl chains (C9-C12) with oligoglucoside moiety with a few (1-3) of glucose units. It was also described that regulation of the dispersibility of the molecular assemblies prepared by diol-boron complexation between the sugar moiety on AOG and boric acid in a dispersion medium. The molecular assembly of AOG was successfully formed by mixing AOG and cholesterols (CH). When using a suitable amount of CH (20-40 mol% with respect to AOG), the molecular assembly formed a vesicle structure. The dispersion ability of the resulting vesicle was dependent on both the boric acid concentration and pH of the dispersion medium. The light-scattering and ζ-potential measurements revealed that high concentrations (≥10 mM) of boric acid improved dispersibility the vesicles. In contrast, the vesicle agglomerated at low concentrations of boric acid (1-7.5 mM). In the absence of boric acid in dispersion medium, the vesicles were completely agglomerated. The optimum pH range for vesicle dispersion was found to be from neutral to basic (7.4-10.1). The (11)B NMR study revealed that borate ester formation occurred between boric acid and the diol of the sugar moiety on AOG vesicle. The present data suggest that borate ester formation that occurred on the surface of the vesicle provided negative charge to the vesicles, contributing to their dispersion via repulsive forces.

  19. Monte Carlo simulation of a very high resolution thermal neutron detector composed of glass scintillator microfibers.

    PubMed

    Song, Yushou; Conner, Joseph; Zhang, Xiaodong; Hayward, Jason P

    2016-02-01

    In order to develop a high spatial resolution (micron level) thermal neutron detector, a detector assembly composed of cerium doped lithium glass microfibers, each with a diameter of 1 μm, is proposed, where the neutron absorption location is reconstructed from the observed charged particle products that result from neutron absorption. To suppress the cross talk of the scintillation light, each scintillating fiber is surrounded by air-filled glass capillaries with the same diameter as the fiber. This pattern is repeated to form a bulk microfiber detector. On one end, the surface of the detector is painted with a thin optical reflector to increase the light collection efficiency at the other end. Then the scintillation light emitted by any neutron interaction is transmitted to one end, magnified, and recorded by an intensified CCD camera. A simulation based on the Geant4 toolkit was developed to model this detector. All the relevant physics processes including neutron interaction, scintillation, and optical boundary behaviors are simulated. This simulation was first validated through measurements of neutron response from lithium glass cylinders. With good expected light collection, an algorithm based upon the features inherent to alpha and triton particle tracks is proposed to reconstruct the neutron reaction position in the glass fiber array. Given a 1 μm fiber diameter and 0.1mm detector thickness, the neutron spatial resolution is expected to reach σ∼1 μm with a Gaussian fit in each lateral dimension. The detection efficiency was estimated to be 3.7% for a glass fiber assembly with thickness of 0.1mm. When the detector thickness increases from 0.1mm to 1mm, the position resolution is not expected to vary much, while the detection efficiency is expected to increase by about a factor of ten.

  20. Recombinant chimeric vaccine composed of PRRSV antigens and truncated Pseudomonas exotoxin A (PE-K13).

    PubMed

    Yang, Hsin-Ping; Wang, Tsan-Chih; Wang, Shiou-Jen; Chen, Shih-Ping; Wu, Eva; Lai, Shao-Qun; Chang, Hsueh-Wei; Liao, Chao-Wei

    2013-10-01

    A Pseudomonas exotoxin (PE-KDEL)-based chimeric subunit vaccine system was recently developed using a reverse vaccinology technique. In this study, the plasmids containing PE-PRRS chimeric subunits were constructed that composed of porcine reproductive and respiratory syndrome virus (PRRSV) antigen moieties, a ligand moiety and a Pseudomonas exotoxin A deleted domain III (PE (ΔIII)), and a carboxyl terminal moiety that includes a polypeptide with amino acid sequence KDEL (K3). The PE-PRRS combination vaccine can effectively induce not only PRRSV-specific INF-γ cellular immunity but also a slow-reacting and complement-requiring type serum neutralizing antibody in pigs. In a specific pathogen free (SPF) pig challenge model, body temperature (colonic temperature), occurrence of PRRSV viremia, nasal excretions, gross and histopathological appearances of pneumonia, and serum antibody activity (IFA and SN) titers significantly differed between the immunized group and the control group. The survey showed that a 0.3mg/dose PE-PRRS vaccine formula conferred protection against PRRSV. A field trial of PE-PRRS vaccine was performed to study the immune response of pregnant sows after vaccination in a PRRSV persist farm. The RT-PCR analysis of viremia and serological titers showed that the PE-PRRS vaccine not only increased sow reproductive performance and evoked its immune response to PRRS viremia, it also activated maternal immune protections to prevent piglets from inflicting viremia. In conclusion, we developed a novel and effective PRRS cytotoxic T-cells (CTLs)-based vaccine containing Pseudomonas exotoxin (PE-KDEL) carrier in combination with PRRSV conserved epitopes against PRRS virus.

  1. Interaction of melittin with mixed phospholipid membranes composed of dimyristoylphosphatidylcholine and dimyristoylphosphatidylserine studied by deuterium NMR

    SciTech Connect

    Dempsey, C.; Bitbol, M.; Watts, A. )

    1989-08-08

    The interaction of bee venom melittin with mixed phospholipid bilayers composed of dimyristoylphosphatidylcholine deuterated in the {alpha}- and {beta}-methylenes of the choline head group (DMPC-d{sub 4}) and dimyristoylphosphatidylserine deuterated in the {alpha}-methylene and {beta}-CH positions of the serine head group (DMPS-d{sub 3}) was studied in ternary mixtures by using deuterium NMR spectroscopy. The changes in the deuterium quadrupole splittings of the head-group deuteriomethylenes of DMPC-d{sub 4} induced by DMPS in binary mixtures were systematically reversed by increasing concentrations of melittin, so that at a melittin concentration of 4 mol % relative to total lipid the deuterium NMR spectrum from DMPC-d{sub 4} in the ternary mixture was similar to the spectrum from pure DMPC-d{sub 4} bilayers. The absence of deuterium NMR signals arising from melittin-bound DMPS in ternary mixtures containing DMPS-d{sub 3} indicates that the reversal by melittin of the effects of DMPS on the quadrupole splittings of DMPC-d{sub 4} results from the response of the choline head group to the net surface charge rather than from phase separation of melittin-DMPS complexes. The similarity in the effects of the two cationic but otherwise dissimilar peptides indicates that the DMPS head group responds to the surface charge resulting from the presence in the bilayer of charged amphiphiles, in a manner analogous to the response of the choline head group of phosphatidylcholine to the bilayer surface charge. The presence of DMPS greatly stabilized DMPC bilayers with respect to melittin-induced micellization, indicating that the latter effect of melittin may not be important for the hemolytic activity of the peptide.

  2. Monte Carlo simulations of spectral albedo for artificial snowpacks composed of spherical and nonspherical particles.

    PubMed

    Tanikawa, Tomonori; Aoki, Teruo; Hori, Masahiro; Hachikubo, Akihiro; Abe, Osamu; Aniya, Masamu

    2006-07-20

    The optical properties of snowpacks composed of spherical and nonspherical particles artificially prepared in a cold laboratory are investigated by measuring spectral albedos. The measured spectral albedo in the spectral region lambda=0.35-2.5 microm is compared with the theoretically calculated albedo, for which a Monte Carlo radiative transfer model is employed for multiple scattering combined with the Mie theory and the ray-tracing technique for single scattering by snow particles. Since the spherical particles are a little aggregate, the effects of a cluster of the spheres on snow albedo are examined using a generalized multiparticle Mie-solution model [Appl. Opt. 34, 4573 (1995); J. Quant. Spectrosc. Radiat. Transf. 79-80, 1121 (2003)]. The snow albedo of a cluster of the spheres can be represented with that of the singe sphere slightly larger than its component of the cluster in case of small grains. The observed albedos for the spherical snow particles agree with the theoretically calculated ones for the snow grain size measured in the snow pit work. The snow albedos for the nonspherical particles, which were dendrites, are influenced by the branch width and the branch length, based on a comparison of the theoretically calculated albedo by using circular cylindrical snow particles and the observed albedo. The snow albedo in the near-infrared region depends on the branch width only when the branch length is sufficiently greater than the branch width. The comparison between the spherical and nonspherical snow particles indicates that the spectral albedo of the nonspherical particles can be represented by using an equal volume-area ratio sphere.

  3. Evaluation of semi-interpenetrating polymer networks composed of chitosan and poloxamer for wound dressing application.

    PubMed

    Kim, I Y; Yoo, M K; Seo, J H; Park, S S; Na, H S; Lee, H C; Kim, S K; Cho, C S

    2007-08-16

    We have elsewhere reported the work on the preparation of semi-interpenetrating polymer networks (SIPNs) composed of chitosan (CS) and poloxamer to improve the mechanical strength of CS sponge. This study focuses on evaluation of the CS/poloxamer SIPNs to intend for wound dressing application and the efficacy of dehydroepiandrosterone (DHEA)-loaded CS/poloxamer SIPNs in the wound model studies. The properties required for ideal wound dressing, such as equilibrium water content (EWC), water absorption (A(w)), water vapor transmission rate (WVTR), and evaporative water loss, were examined. The CS/poloxamer SIPNs were found to have a water content of 90% of their weight which could prevent the wound bed from accumulation of exudates and also have excellent water adsorption. The WVTR of CS/poloxamer SIPNs was found to be 2,508.2+/-65.7gm(-2)day(-1), indicating that the SIPNs can maintain a moist environment over wound bed in moderate to heavily exuding wound which enhances epithelial cell migration during the healing process. Also, the CS/poloxamer SIPNs in vitro assessment showed proper biodegradation and low cytotoxicity for wound dressing application. The wound healing efficacy of CS/poloxamer SIPNs as a wound dressing was evaluated on experimental full thickness wounds in a mouse model. It was found that the wounds covered with CS/poloxamer SIPNs or DHEA-loaded CS/poloxamer SIPNs were completely filled with new epithelium without any significant adverse reactions after 3 weeks. The results thus indicate that CS/poloxamer SIPNs could be employed in the future as potential wound dressing materials.

  4. Structural characterization of the enzymes composing the arginine deiminase pathway in Mycoplasma penetrans.

    PubMed

    Gallego, Pablo; Planell, Raquel; Benach, Jordi; Querol, Enrique; Perez-Pons, Josep A; Reverter, David

    2012-01-01

    The metabolism of arginine towards ATP synthesis has been considered a major source of energy for microorganisms such as Mycoplasma penetrans in anaerobic conditions. Additionally, this pathway has also been implicated in pathogenic and virulence mechanism of certain microorganisms, i.e. protection from acidic stress during infection. In this work we present the crystal structures of the three enzymes composing the gene cluster of the arginine deiminase pathway from M. penetrans: arginine deiminase (ADI), ornithine carbamoyltransferase (OTC) and carbamate kinase (CK). The arginine deiminase (ADI) structure has been refined to 2.3 Å resolution in its apo-form, displaying an "open" conformation of the active site of the enzyme in comparison to previous complex structures with substrate intermediates. The active site pocket of ADI is empty, with some of the catalytic and binding residues far from their active positions, suggesting major conformational changes upon substrate binding. Ornithine carbamoyltransferase (OTC) has been refined in two crystal forms at 2.5 Å and 2.6 Å resolution, respectively, both displaying an identical dodecameric structure with a 23-point symmetry. The dodecameric structure of OTC represents the highest level of organization in this protein family and in M.penetrans it is constituted by a novel interface between the four catalytic homotrimers. Carbamate kinase (CK) has been refined to 2.5 Å resolution and its structure is characterized by the presence of two ion sulfates in the active site, one in the carbamoyl phosphate binding site and the other in the β-phosphate ADP binding pocket of the enzyme. The CK structure also shows variations in some of the elements that regulate the catalytic activity of the enzyme. The relatively low number of metabolic pathways and the relevance in human pathogenesis of Mycoplasma penetrans places the arginine deiminase pathway enzymes as potential targets to design specific inhibitors against this human

  5. Neisseria meningitidis Type IV Pili Composed of Sequence Invariable Pilins Are Masked by Multisite Glycosylation

    PubMed Central

    Gault, Joseph; Ferber, Mathias; Machata, Silke; Imhaus, Anne-Flore; Malosse, Christian; Charles-Orszag, Arthur; Millien, Corinne; Bouvier, Guillaume; Bardiaux, Benjamin; Péhau-Arnaudet, Gérard; Klinge, Kelly; Podglajen, Isabelle; Ploy, Marie Cécile; Seifert, H. Steven; Nilges, Michael; Chamot-Rooke, Julia; Duménil, Guillaume

    2015-01-01

    The ability of pathogens to cause disease depends on their aptitude to escape the immune system. Type IV pili are extracellular filamentous virulence factors composed of pilin monomers and frequently expressed by bacterial pathogens. As such they are major targets for the host immune system. In the human pathogen Neisseria meningitidis, strains expressing class I pilins contain a genetic recombination system that promotes variation of the pilin sequence and is thought to aid immune escape. However, numerous hypervirulent clinical isolates express class II pilins that lack this property. This raises the question of how they evade immunity targeting type IV pili. As glycosylation is a possible source of antigenic variation it was investigated using top-down mass spectrometry to provide the highest molecular precision on the modified proteins. Unlike class I pilins that carry a single glycan, we found that class II pilins display up to 5 glycosylation sites per monomer on the pilus surface. Swapping of pilin class and genetic background shows that the pilin primary structure determines multisite glycosylation while the genetic background determines the nature of the glycans. Absence of glycosylation in class II pilins affects pilus biogenesis or enhances pilus-dependent aggregation in a strain specific fashion highlighting the extensive functional impact of multisite glycosylation. Finally, molecular modeling shows that glycans cover the surface of class II pilins and strongly decrease antibody access to the polypeptide chain. This strongly supports a model where strains expressing class II pilins evade the immune system by changing their sugar structure rather than pilin primary structure. Overall these results show that sequence invariable class II pilins are cloaked in glycans with extensive functional and immunological consequences. PMID:26367394

  6. Active control of sound transmission through partitions composed of discretely controlled modules

    NASA Astrophysics Data System (ADS)

    Leishman, Timothy W.

    This thesis provides a detailed theoretical and experimental investigation of active segmented partitions (ASPs) for the control of sound transmission. ASPs are physically segmented arrays of interconnected acoustically and structurally small modules that are discretely controlled using electronic controllers. Theoretical analyses of the thesis first address physical principles fundamental to ASP modeling and experimental measurement techniques. Next, they explore specific module configurations, primarily using equivalent circuits. Measured normal-incidence transmission losses and related properties of experimental ASPs are determined using plane wave tubes and the two-microphone transfer function technique. A scanning laser vibrometer is also used to evaluate distributed transmitting surface vibrations. ASPs have the inherent potential to provide excellent active sound transmission control (ASTC) through lightweight structures, using very practical control strategies. The thesis analyzes several unique ASP configurations and evaluates their abilities to produce high transmission losses via global minimization of normal transmitting surface vibrations. A novel dual diaphragm configuration is shown to employ this strategy particularly well. It uses an important combination of acoustical actuation and mechano-acoustical segmentation to produce exceptionally high transmission loss (e.g., 50 to 80 dB) over a broad frequency range-including lower audible frequencies. Such performance is shown to be comparable to that produced by much more massive partitions composed of thick layers of steel or concrete and sand. The configuration uses only simple localized error sensors and actuators, permitting effective use of independent single-channel controllers in a decentralized format. This work counteracts the commonly accepted notion that active vibration control of partitions is an ineffective means of controlling sound transmission. With appropriate construction, actuation

  7. Technical Evaluation Report on the Guidance and Control Panel 53rd Symposium on Air Vehicle Mission Control and Management (La Gestion et le Controle des Missions des Vehicules Aeriens)

    DTIC Science & Technology

    1992-07-01

    d’importance dans le guidage et le pilotage des vehicules aeriens. Les developpements dans ce domaine representent des contributions d’une importance...d’un vehicule non-pilots. fonctionner en mode automatique. Les communications techniques ont examine les realisations et les tendances actuelles dans...le domaine de la gestion des missions des vehicules aeriens, presente !’tat de I’art et propos, des solutions technologiques pour la conception des

  8. Rôle des hyrates dans la formation de Titan et des satellites réguliers

    NASA Astrophysics Data System (ADS)

    Mousis, O.

    2001-12-01

    Cette these est dediee a l'etude de l'origine de Titan et de son atmosphere. Dans l'hypothese ou la subnebuleuse de Saturne etait geometriquement mince, le modele de disque turbulent utilise, derive des travaux de Dubrulle (1993), est moins dense que le modele de Prinn et Fegley (1981). De ce fait, les conversions de Co en CH4 et de N2 en NH3 ont ete inhibees dans la subnebuleuse, contrairement a ce qui est couramment admis pour interpreter la presence du methane dans l'atmosphere de Titan. C'est pourquoi nous avons developpe un nouveau scenario de la formation de titan, qui tient compte simultanement des contraintes resultant de la chimie de la subnebuleuse et des abondances de CH4, N2 et CH3D mesurees dans l'atmosphere du satellite. Nous faisons l'hypothese que ces gaz proviennent initialement de la vaporisation du nuage presolaire, qui s'effondra et forma le Soleil et son disque environnant. Lors du refroidissement de la nebuleuse, les volatils auraient ete pieges sous formes de clathrates d'hydrates dans les grains, puis dans les planetesimaux qu'ils formerent. Les planetesimaux hydrates a l'origine de la formation de Titan seraient alors des rescapes de l'effondrement hydsrodynamique de la feeding zone de Saturne. Ce scenario a ete applique aux subnebuleuses de Jupiter et d'Uranus, et a apporte un certain nombre de contraintes sur la formation des satellites reguliers de ces planetes. Le temps et la zone de formation des grains cometaires ont egalement ete estimes dans la nebuleuse solaire. Enfin, l'etude experimentale de la temperature de fusion du dihydrate d'ammoniac dans la gamme des hautes pressions a apporte des nouvelles donnees thermodynamiques qui permettront d'ameliorer les modeles de l'interieur de Titan.

  9. Dismantling processes of basaltic shield volcanoes - origin of the Piton des Neiges breccias - Reunion Island

    NASA Astrophysics Data System (ADS)

    Arnaud, A.; Bachèlery, B.; Cruchet, C.

    2003-04-01

    Reunion Island is mainly composed by two volcanic massifs: the active Piton de la Fournaise to the southeast and the Piton des Neiges to the northwest that has been inactive for about 12000 years. The latter corresponds to a dismantled volcanic massif, deeply cut by valleys and by three vast depressions, called “cirques” around the centre of the volcano. They offer the opportunity to observe the inside of a basaltic shield volcano. The first work dealing with the origin of the “cirques” very quickly showed the existence of a significant cover of breccia deposits. These breccias were often interpreted as the result of a major stage of erosion considered as partly at the origin of the “cirques” formation. Geological campaigns mainly achieved in the “cirque de Salazie” (eastern of the Piton des Neiges), allow to establish a first typology based on morphological, phenomenological and sedimentary features of the deposits. Two main complexes of breccias have been distinguished. An old complex outcropping in the internal parts of the cirque and an upper complex generally overlaying the lower complex. The old complex comprises two main units of breccias. These units show a strong alteration marked by the presence of clays, chlorites, serpentines and zeolites. In the inner part of the cirque, these breccias are closely related to the old lava formations from which they come. These units show frequent jigsaw-cracks, a chaotic stratigraphy, as well as large amounts of chlorite. The upper complex is constituted by four main units which are more or less geographically separated in the cirque of Salazie. Their limits are not yet well identified because of the significant relief and a strong vegetable cover. Several units display a very strong fracturation, jigsaw-cracks and a chaotic stratigraphy whereas many lava flows are pulverised and locally injected in scoria levels. Recent work on Saint-Gilles breccias (Fèvre et al., this meeting) allowed to identify

  10. Photopolymérisation des monomères multifonctionnels dans une matrice polymère Effet de différents paramètres sur la réactivité des monomères

    NASA Astrophysics Data System (ADS)

    Bendaikha, T.; Boussaad, S.; Boutamdja, M.

    2005-05-01

    Un matériau polymère semi-interpénétré a été obtenu par polymérisation d'un monomère diacrylate, le tripropylène glycol diacrylate (TPGDA) ou le 1,6-hexanediol diacrylate (HDDA) dispersé dans une matrice organique qui est le polystyrène ou le copolymère élastomérique SBS. L'amorçage de la réaction se fait par voie photochimique en utilisant des photoamorceurs qui se décomposent rapidement sous l'action des radiations UV émises par une lampe à vapeur de mercure. La cinétique de la réaction a été suivie quantitativement par spectroscopie IR. Les effets de plusieurs paramètres sur la vitesse de la polymérisation ont été étudiés.

  11. C3I for Crisis, Emergency and Consequence Management (C3I pour la gestion des crises, des urgences et de leurs consequences)

    DTIC Science & Technology

    2009-05-01

    May 2009 C3I for Crisis, Emergency and Consequence Management (C3I pour la gestion des crises , des urgences et de leurs conséquences) Research and...consequence management. ES - 2 RTO-MP-IST-086 C3I pour la gestion des crises , des urgences et de leurs conséquences (RTO-MP-IST-086...contre-terrorisme, de sécurité nationale/publique et de réponse collective face aux situations d’urgence (à la fois gestion des crises et gestion de leurs

  12. Reconnaissance optique des formes en parallele utilisant des reseaux de neurones et une mire de reduction de dimensions

    NASA Astrophysics Data System (ADS)

    Gagne, Philippe

    Cette recherche vise à la mise en OEuvre optique de la reconnaissance des images en utilisant une mire d'anneaux afin de générer des vecteurs caractéristiques qui seront ensuite classifiés par un réseau de neurones. On proposera deux architectures originales: une qui permettra la reconnaissance invariante sous rotation en utilisant un corrélateur conjoint; l'autre montage permettra une classification en parallèle de plusieurs images grâce à la capacité des mires d'anneaux de compresser l'information. Ce dernier montage est basé sur un corrélateur 4F. On présentera des résultats optiques expérimentaux pour ces deux montages. Pour arriver à des résultats concluants on analysera le comportement des vecteurs obtenus à partir d'une mire d'anneaux, on introduira une règle d'apprentissage optimisant le pic de corrélation en réduisant les pics parasites et on corrigera à l'aide d'un algorithme génétique les modulations de phases générées par le modulateur spatial à cristaux liquides.

  13. The ``Ciel, miroir des cultures'' exhibition: a three-year awareness campaign on the sky as a mirror of cultures

    NASA Astrophysics Data System (ADS)

    Las Vergnas, Olivier; Piednoël, Eric; Gautier, Gérard

    2011-06-01

    The Ciel, miroir des cultures poster-exhibition was designed by the Association Française d'Astronomie and printed in 300 copies in 2005. Each copy is composed of 14 posters introducing the different ways human beings and societies have used the sky and the heavens in history. More than three hundred cultural events have now been using the exhibition in schools and community structures as public libraries and social centres, taking place mainly in low-income urban or suburban neighbourhoods. This three-year work demonstrated the relevance of this kind of tools and events to pedagogical and social aims, specifically if the event is not limited to showing posters and also offers an opportunity for dialogue.

  14. Les sarcomes des tissus mous: à propos de 33 cas

    PubMed Central

    Abdou, Jiddou; Elkabous, Mustapha; M'rabti, Hind; Errihani, Hassan

    2015-01-01

    L'objectif de cette étude est de rapporter les particularités épidémiologiques, cliniques, histologiques, thérapeutiques et évolutives des sarcomes des tissus mous à l'Institut National d'Oncologie et de définir les facteurs influençant la survie des patients. C'est une étude rétrospective de 33 cas de sarcome des tissus mous, colligés entre janvier 2008 et décembre 2010. Les critères d’éligibilité étaient un âge supérieur à 16 ans, une épreuve histologique d'un sarcome des tissus mous à l'exclusion des tumeurs stromales gastro-intestinales (GIST). Les items recueillis étaient: épidémiologiques, cliniques, histologiques, Radiologiques, et thérapeutiques. Des analyses univariées puis multivariées ont été réalisées à la recherche de facteurs influençant la survie à 2 ans. Il s'agit de 33 cas, 17 Hommes et 16 Femmes, l’âge moyen était de 43,21 ans (Extrêmes= 18-76 ans). La tumeur était localisée aux extrémités dans 24 cas (72,72%). Le type histologique prédominant était le Liposarcome dans 9 cas (27,27%). Le stade tumoral était localisé dans 25 cas (75,8%), métastatique dans 8 cas (24,2%). Vingt-cinq tumeurs ont été traitées chirurgicalement dont 21 cas (84%) de chirurgie conservatrice et 4 cas (16%) de chirurgie radicale. La radiothérapie a été réalisée chez 10 patients (30,3%). La chimiothérapie a été faite chez 20 patients. En analyse univariée les facteurs pronostiques étaient l’âge (p=0,03) et le stade tumoral (p=0,09). L’âge et le stade tumoral sont des facteurs pronostiques influençant la survie des sarcomes des tissus mous. PMID:27022434

  15. Nouvelle approche à la prise en charge des condylomes

    PubMed Central

    Lopaschuk, Catharine C.

    2013-01-01

    Résumé Objectif Faire le résumé des anciens et des nouveaux moyens de traitement des verrues génitales ou condylomes et déterminer comment les utiliser de manière appropriée. Sources des données Une recherche documentaire a été effectuée dans les bases de données suivantes: MEDLINE, PubMed, EMBASE, base de données des synthèses systématiques et registre central des études contrôlées de la Collaboration Cochrane (en anglais), ACP Journal Club et Trip. Les bibliographies des articles extraits ont aussi été examinées. Les études cliniques, les articles de révision qualitative, les rapports consensuels et les guides de pratique clinique ont été retenus. Message principal Les verrues symptomatiques sont présentes chez au moins 1 % des personnes âgées entre 15 et 49 ans et on estime que jusqu’à 50 % des gens sont infectés par le virus du papillome humain à un moment donné de leur vie. L’imiquimod et la podophyllotoxine sont 2 nouveaux traitements pour les verrues génitales externes qui sont moins douloureux et peuvent être appliqués par les patients à la maison. De plus, il a été démontré que le vaccin quadrivalent contre le virus du papillome humain est efficace pour prévenir les condylomes et le cancer du col. Les plus anciennes méthodes thérapeutiques ont aussi leur place dans certaines situations, comme les verrues intravaginales, urétrales, anales ou récalcitrantes ou encore pour les patientes enceintes. Conclusion Les nouveaux traitements des verrues génitales externes peuvent réduire la douleur causée par la thérapie et le nombre de visites au cabinet. Les autres méthodes thérapeutiques demeurent utiles dans certaines situations.

  16. Caractérisation des convertisseurs matriciels : II. Synthèse des fonctions de connexion

    NASA Astrophysics Data System (ADS)

    François, B.; Cambronne, J. P.; Hautier, J. P.

    1996-05-01

    Knowing the wished conversion levels (-1,0,1) of a power converter, this paper describes a particular method for setting the corresponding states of switches into the matrix converter. In a first step, a mathematical analysis establishes the relations linking the states of switches with the conversion functions. Afterwards, the presented method gives the inverse relations which constitute the sequential part of the converter control. The turn-on and the turn-off sequences are designed by considering the on-line wished level conversions. This general method enhances the idea that a converter functionnality must be defined by its structure and its control. Cet article propose une méthode originale pour définir la séquence de commande d'un convertisseur à partir de la fonction de conversion globalement souhaitée. Les auteurs procèdent d'abord à une analyse mathématique précise des relations qui existent entre les états des interrupteurs et les fonctions de conversion obtenues. À partir de cette analyse, la méthode developpée permet d'établir systématiquement les relations inverses qui constituent alors le module séquentiel de la commande rapprochée du convertisseur. Les ordres d'ouverture et de fermeture des interrupteurs sont élaborés en considérant à tout instant les niveaux de conversion souhaités pour les grandeurs électriques. Cette méthode générale renforce l'idée que la fonction remplie par un convertisseur moderne doit être définie à la fois par sa structure et sa commande.

  17. Étude analytique des perturbations solaires des satellites d'Uranus.

    NASA Astrophysics Data System (ADS)

    Dumoulin, C.; Laskar, J.

    1990-12-01

    Ce travail s'insère dans le cadre de la General Uranian Satellites Theory de J. Laskar (1986) et Laskar et Jacobson (1987), qui donne une solution analytique du mouvement des cinq principaux satellites d'Uranus, incluant les perturbations mutuelles et la perturbation due à l'aplatissement de la planète. Les perturbations solaires dont il n'avaient pas été tenu compte dans cette étude ont été calculées pour tous les éléments orbitaux de chaque satellite.

  18. Relations de Dispersion et Diffusion des Glueballs et des Mesons dans la Theorie de Jauge U(1)(2+1) Compacte

    NASA Astrophysics Data System (ADS)

    Ahmed, Chaara El Mouez

    Nous avons etudie les relations de dispersion et la diffusion des glueballs et des mesons dans le modele U(1)_{2+1} compact. Ce modele a ete souvent utilise comme un simple modele de la chromodynamique quantique (QCD), parce qu'il possede le confinement ainsi que les etats de glueballs. Par contre, sa structure mathematique est beaucoup plus simple que la QCD. Notre methode consiste a diagonaliser l'Hamiltonien de ce modele dans une base appropriee de graphes et sur reseau impulsion, afin de generer les relations de dispersion des glueballs et des mesons. Pour la diffusion, nous avons utilise la methode dependante du temps pour calculer la matrice S et la section efficace de diffusion des glueballs et des mesons. Les divers resultats obtenus semblent etre en accord avec les travaux anterieurs de Hakim, Alessandrini et al., Irving et al., qui eux, utilisent plutot la theorie des perturbations en couplage fort, et travaillent sur un reseau espace-temps.

  19. La planification préalable des soins pour les patients en pédiatrie

    PubMed Central

    2008-01-01

    RÉSUMÉ Les progrès médicaux et technologiques ont permis d’ac-croître les taux de survie et d’améliorer la qualité de vie des nourrissons, des enfants et des adolescents ayant des maladies chroniques mettant la vie en danger. La planifi-cation préalable des soins inclut le processus relié aux discussions sur les traitements essentiels au maintien de la survie et la détermination des objectifs des soins de longue durée. Les dispensateurs de soins pédiatriques ont l’obligation éthique d’assimiler cet aspect des soins médicaux. Le présent document de principes vise à aider les dispensateurs de soins à discuter de la planification préalable des soins des patients pédiatriques dans diverses situations. La planification préalable des soins exige des communications efficaces afin de clarifier les objectifs des soins et de s’entendre sur les traitements pertinents ou non pour réaliser ces objectifs, y compris les mesures de réanimation et les mesures palliatives.

  20. Thermo-electrical properties of composite semiconductor thin films composed of nanocrystalline graphene-vanadium oxides.

    PubMed

    Jung, Hye-Mi; Um, Sukkee

    2014-12-01

    This paper presents an experimental comparative study involving the characterization of the thermo-electrical and structural properties of graphene-based vanadium oxide (graphene-VOx) composite thin films on insulating and conducting surfaces (i.e., fused quartz and acrylic resin-impregnated graphite) produced by a sol-gel process via dipping-pyrolysis. A combination of FE-SEM and XPS analyses revealed that the graphene-VOx composite thin films (coated onto fused quartz) exhibiting the microstructure of 2-graded nanowire arrays with a diameter of 40-80 nm were composed of graphene, a few residual oxygen-containing functional groups (i.e., C-O and C=O), and the VO2 Magnéli phase. The temperature-dependent electrical resistance measured on the as-deposited thin films clearly demonstrated that the graphene-VOx composite nanowire arrays thermally grown on fused quartz act as a semiconductor switch, with a transition temperature of 64.7 degrees C in the temperature range of -20 degrees C to 140 degrees C, resulting from the contributions of graphene and graphene oxides. In contrast, the graphene-VOx composite thin films deposited onto acrylic resin-impregnated graphite exhibit a superlinear semiconducting property of extremely low electrical resistance with negative temperature coefficients (i.e., approximately four orders of magnitude lower than that of the fused quartz), despite the similar microstructural and morphological characteristics. This difference is attributed to the synergistic effects of the paramagnetic metal feature of the tightly stacked nanowire arrays consisting of hexagonal V2O3 on the intrinsic electrical properties of the acrylic resin-impregnated graphite substrate, as revealed by FE-SEM, EDX, AFM, and XRD measurements. Although the thermo-sensitive electrical properties of the graphene-VOx composite thin films are very substrate specific, the applicability of graphene sheets can be considerably effective in the formation of highly planar arrays

  1. Modeling of mitochondria bioenergetics using a composable chemiosmotic energy transduction rate law: theory and experimental validation.

    PubMed

    Chang, Ivan; Heiske, Margit; Letellier, Thierry; Wallace, Douglas; Baldi, Pierre

    2011-01-01

    Mitochondrial bioenergetic processes are central to the production of cellular energy, and a decrease in the expression or activity of enzyme complexes responsible for these processes can result in energetic deficit that correlates with many metabolic diseases and aging. Unfortunately, existing computational models of mitochondrial bioenergetics either lack relevant kinetic descriptions of the enzyme complexes, or incorporate mechanisms too specific to a particular mitochondrial system and are thus incapable of capturing the heterogeneity associated with these complexes across different systems and system states. Here we introduce a new composable rate equation, the chemiosmotic rate law, that expresses the flux of a prototypical energy transduction complex as a function of: the saturation kinetics of the electron donor and acceptor substrates; the redox transfer potential between the complex and the substrates; and the steady-state thermodynamic force-to-flux relationship of the overall electro-chemical reaction. Modeling of bioenergetics with this rate law has several advantages: (1) it minimizes the use of arbitrary free parameters while featuring biochemically relevant parameters that can be obtained through progress curves of common enzyme kinetics protocols; (2) it is modular and can adapt to various enzyme complex arrangements for both in vivo and in vitro systems via transformation of its rate and equilibrium constants; (3) it provides a clear association between the sensitivity of the parameters of the individual complexes and the sensitivity of the system's steady-state. To validate our approach, we conduct in vitro measurements of ETC complex I, III, and IV activities using rat heart homogenates, and construct an estimation procedure for the parameter values directly from these measurements. In addition, we show the theoretical connections of our approach to the existing models, and compare the predictive accuracy of the rate law with our experimentally

  2. Large landslides, composed of megabreccia, interbedded in Miocene basin deposits, southeastern Arizona

    USGS Publications Warehouse

    Krieger, Medora Louise Hooper

    1977-01-01

    The landslides in the Kearny and El Capitan Mountain quadrangles, Pinal and Gila Counties, Ariz., are tabular or lens like masses of megabreccia enclosed in Miocene basin deposits. The megabreccias within individual slide blocks are composed of pervasively brecciated Precambrian and younger formations that remain in normal stratigraphic sequence, indicating that each landslide moved as a fairly coherent mass. The megabreccias consist of fresh, mostly angular rock fragments in a comminuted matrix of the same composition as the fragments. The matrix ranges in amount from sparse to abundant. Where the matrix is sparse, the fragments fit tightly with little or no rotation. Locally fragments are rotated but not moved far; most units within a slide block are lithologically homogeneous. The Kearny landslides are conformably interbedded in steeply east-dipping playa and alluvial deposits. They form map units from a few tens of meters to nearly 4 km long and from less than 1 to 270 m wide. Narrow ridges expose sections through the landslides at about right angles to the direction of movement. The upper (proximal) ends have been eroded; the lower (distal) ends are buried. The El Capitan landslide dips very gently southward. Although partly dissected during erosion of the enclosing alluvial and lakebed deposits, its approximate original outline is still preserved. It forms a thin sheet, 5-15 m thick and at least 3.8 km long; the maximum outcrop width, near its distal end, is about 1.5 km. The Kearny landslides show little evidence of having exerted differential pressure on the underlying soft playa and alluvial deposits, and the contacts with the underlying sediments have little relief. The distal end of the El Capitan landslide, on the other hand, has considerable relief. As the landslide came to an abrupt stop, the end plowed into the underlying sediments, compressing them into fol9.s and forming sandstone dikes. The source of the El Capitan landslide is a well

  3. Unmasking the effect of a precipitation pulse on the biological processes composing Net Ecosystem Carbon Exchange

    NASA Astrophysics Data System (ADS)

    Lopez-Ballesteros, Ana; Sanchez-Cañete, Enrique P.; Serrano-Ortiz, Penelope; Oyonarte, Cecilio; Kowalski, Andrew S.; Perez-Priego, Oscar; Domingo, Francisco

    2015-04-01

    Drylands occupy 47.2% of the global terrestrial area and are key ecosystems that significantly determine the inter-annual variability of the global carbon balance. However, it is still necessary to delve into the functional behavior of arid and semiarid ecosystems due to the complexity of drivers and interactions between underpinning processes (whether biological or abiotic) that modulate net ecosystem CO2 exchange (NEE). In this context, water inputs are crucial to biological organisms survival in arid ecosystems and frequently arrive via rain events that are commonly stochastic and unpredictable (i.e. precipitation pulses) and strongly control arid land ecosystem structure and function. The eddy covariance technique can be used to investigate the effect of precipitation pulses on NEE, but provide limited understanding of what exactly happens after a rain event. The chief reasons are that, firstly, we cannot measure separately autotrophic and heterotrophic components, and secondly, the partitioning techniques widely utilized to separate Gross Primary Production and Total Ecosystem Respiration, do not work properly in these water-limited ecosystems, resulting in biased estimations of plant and soil processes. Consequently, it is essential to combine eddy covariance measurements with other techniques to disentangle the different biological processes composing NEE that are activated by a precipitation pulse. Accordingly, the main objectives of this work were: (i) to quantify the contribution of precipitation pulse events to annual NEE using the eddy covariance technique in a semiarid steppe located in Almería (Spain), and (ii) to simulate a realistic precipitation pulse in order to understand its effect on the ecosystem, soil and plant CO2 exchanges by using a transitory-state closed canopy chamber, soil respiration chambers and continuous monitoring CO2 sensors inserted in the subsoil. Preliminary results showed, as expected, a delay between soil and plant

  4. Formation of Core-Shell Nanoparticles Composed of Magnetite and Samarium Oxide in Magnetospirillum magneticum Strain RSS-1.

    PubMed

    Shimoshige, Hirokazu; Nakajima, Yoshikata; Kobayashi, Hideki; Yanagisawa, Keiichi; Nagaoka, Yutaka; Shimamura, Shigeru; Mizuki, Toru; Inoue, Akira; Maekawa, Toru

    2017-01-01

    Magnetotactic bacteria (MTB) synthesize magnetosomes composed of membrane-enveloped magnetite (Fe3O4) or greigite (Fe3S4) particles in the cells. Recently, several studies have shown some possibilities of controlling the biomineralization process and altering the magnetic properties of magnetosomes by adding some transition metals to the culture media under various environmental conditions. Here, we successfully grow Magnetospirillum magneticum strain RSS-1, which are isolated from a freshwater environment, and find that synthesis of magnetosomes are encouraged in RSS-1 in the presence of samarium and that each core magnetic crystal composed of magnetite is covered with a thin layer of samarium oxide (Sm2O3). The present results show some possibilities of magnetic recovery of transition metals and synthesis of some novel structures composed of magnetic particles and transition metals utilizing MTB.

  5. Formation of Core-Shell Nanoparticles Composed of Magnetite and Samarium Oxide in Magnetospirillum magneticum Strain RSS-1

    PubMed Central

    Shimoshige, Hirokazu; Nakajima, Yoshikata; Kobayashi, Hideki; Yanagisawa, Keiichi; Nagaoka, Yutaka; Shimamura, Shigeru; Mizuki, Toru; Inoue, Akira; Maekawa, Toru

    2017-01-01

    Magnetotactic bacteria (MTB) synthesize magnetosomes composed of membrane-enveloped magnetite (Fe3O4) or greigite (Fe3S4) particles in the cells. Recently, several studies have shown some possibilities of controlling the biomineralization process and altering the magnetic properties of magnetosomes by adding some transition metals to the culture media under various environmental conditions. Here, we successfully grow Magnetospirillum magneticum strain RSS-1, which are isolated from a freshwater environment, and find that synthesis of magnetosomes are encouraged in RSS-1 in the presence of samarium and that each core magnetic crystal composed of magnetite is covered with a thin layer of samarium oxide (Sm2O3). The present results show some possibilities of magnetic recovery of transition metals and synthesis of some novel structures composed of magnetic particles and transition metals utilizing MTB. PMID:28125741

  6. Catalog Production for the DES Blind Cosmology Challenge

    NASA Astrophysics Data System (ADS)

    Busha, Michael T.; Wechsler, R. H.; Becker, M. R.; Erickson, B.; Evrard, A. E.

    2013-01-01

    The Blind Cosmology Challenge (BCC) is an effort by the Dark Energy Survey (DES) to test analysis tools for extracting cosmological information using a set of detailed synthetic galaxy catalogs. Here, we describe the creation of these synthetic sky catalogs based on requirements of the optical (DES) and the near-IR VISTA Hemisphere Survey, producing catalogs covering a quarter of the sky to z ˜ 2, with sources complete to r ˜ 25. Starting with a nested set of lightcone outputs of large, N-body simulation, galaxies are assigned to the dark matter distribution using an empirical algorithm that is tunable to match observed evolution of low-order galaxy population properties (counts and spatial clustering) in luminosity-color-density space. Galaxies are lensed by matter along the line of sight (including magnification, shape distortion, and multiple images), using a new algorithm that calculates shear with 3.22 arcsec resolution at galaxy positions in the full catalog. The catalog is well suited to support DES+VISTA joint studies of galaxy clustering, groups and clusters of galaxies, and gravitational lensing, and we highlight their application to the ongoing DES BBCC. Catalogs include ˜320 million galaxies and ˜150 million stars, with realistic colors, shapes and photometric errors. Using the expected DES photometric errors, three independent photometric redshift codes are run on the catalog, two of which produce full probability distributions. The synthetic observable catalog includes object position, magnitudes in the DES and VISTA bands, photometric errors, photometric redshifts, size, ellipticity, for each of ˜ 500 million objects. The galaxy distribution is additionally masked appropriately for the 5000 square degree DES footprint, including the impact of bright stars. In addition, we offer separate catalogs with magnitudes for additional existing and planned surveys, including SDSS, CFHTLS, HSC, LSST, and Euclid.

  7. De l'importance des orbites periodiques: Detection et applications

    NASA Astrophysics Data System (ADS)

    Doyon, Bernard

    L'ensemble des Orbites Periodiques Instables (OPIs) d'un systeme chaotique est intimement relie a ses proprietes dynamiques. A partir de l'ensemble (en principe infini) d'OPIs cachees dans l'espace des phases, on peut obtenir des quantites dynamiques importantes telles les exposants de Lyapunov, la mesure invariante, l'entropie topologique et la dimension fractale. En chaos quantique (i.e. l'etude de systemes quantiques qui ont un equivalent chaotique dans la limite classique), ces memes OPIs permettent de faire le pont entre le comportement classique et quantique de systemes non-integrables. La localisation de ces cycles fondamentaux est un probleme complexe. Cette these aborde dans un premier temps le probleme de la detection des OPIs dans les systemes chaotiques. Une etude comparative de deux algorithmes recents est presentee. Nous approfondissons ces deux methodes afin de les utiliser sur differents systemes dont des flots continus dissipatifs et conservatifs. Une analyse du taux de convergence des algorithmes est aussi realisee afin de degager les forces et les limites de ces schemes numeriques. Les methodes de detection que nous utilisons reposent sur une transformation particuliere de la dynamique initiale. Cette astuce nous a inspire une methode alternative pour cibler et stabiliser une orbite periodique quelconque dans un systeme chaotique. Le ciblage est en general combine aux methodes de controle pour stabiliser rapidement un cycle donne. En general, il faut connaitre la position et la stabilite du cycle en question. La nouvelle methode de ciblage que nous presentons ne demande pas de connaitre a priori la position et la stabilite des orbites periodiques. Elle pourrait etre un outil complementaire aux methodes de ciblage et de controle actuelles.

  8. Calculation of the attenuation and phase displacement per unit of length due to rain composed of ellipsoidal drops

    NASA Technical Reports Server (NTRS)

    Maggiori, D.

    1981-01-01

    All of the phenomena which influence the propagation of radiowaves at frequencies above 10 GHz (attenuation, depolarization, scintillation) can by intensified by parameters directly derived from a solution of individual scatter, naturally in addition to be meteorological elements which characterize the physical medium. The diffusion caused by rainy precipitation was studied using Mie's algorithm for rain composed of spherical drops, and Oguchi's algorithm for rain composed of drops in an ellipsoidal form with axes of rotational symmetry arrange along the vertical line of a generic reference point. Specific phase displacement and attenuation along the principal planes, propagation of radiowaves in generic polarization, and propagation with inclined axes are also considered.

  9. Le role du phytoplancton de petite taille (<20 mum) dans les variations des proprietes optiques des eaux du Saint-Laurent

    NASA Astrophysics Data System (ADS)

    Mas, Sebastien

    Les mesures satellitaires de couleur des oceans sont largement determinees par les proprietes optiques inherentes (IOPs) des eaux de surface. D'autre part, le phytoplancton de petite taille (<20 mum) est le plus souvent dominant dans les oceans, et peut donc etre une source importante de variation des IOPs dans les oceans. Dans ce contexte, le but principal de ce doctorat etait de definir l'impact du phytoplancton (<20 mum) sur les variations des proprietes optiques de l'Estuaire et du Golfe du Saint-Laurent (Canada). Afin d'atteindre cet objectif, il etait necessaire de determiner en milieu controle les facteurs de variabilite des proprietes optiques cellulaires et des IOPs du phytoplancton (<20 mum) des eaux du Saint-Laurent, et d'evaluer la contribution du phytoplancton (<20 mum) aux proprietes optiques totales des eaux du Saint-Laurent. Des experiences en laboratoire ont montre que les variations des proprietes optiques des cellules phytoplanctoniques soumises a un cycle jour-nuit, ainsi qu'a des changements concomitants d'intensite lumineuse, peuvent contribuer significativement a la variabilite des proprietes optiques observee en milieu naturel. D'autres experiences ont, quant a elles, mis en evidence que les variations des proprietes optiques des cellules phytoplanctoniques dues aux phases de croissance peuvent alterer les IOPs des oceans, particulierement pendant les periodes de floraison. De plus, la presence de bacteries et de particules detritiques peut egalement affecter la variabilite des IOPs totales, notamment la diffusion. Au printemps, dans l'Estuaire et le Golfe du Saint-Laurent, la contribution du phytoplancton <20 mum aux IOPs presentait des differences regionales evidentes pour les proprietes d'absorption et de diffusion. En plus de la variabilite spatiale, les proprietes optiques cellulaires presentaient des variations journalieres, et ce particulierement pour le picophytoplancton. Enfin, la plupart des differences observees dans les

  10. Bragg Gratings, Photosensitivity, and Poling in Glass Fibers and Waveguides: Applications and Fundamentals. Technical Digest Series, Volume 17

    DTIC Science & Technology

    1998-05-26

    population In Ge doped silica studied by fluorescence spectroscopy, B. Poumellec, H. Cens, Thermodynamique et Physico-Chimie des Matiriaux, France...silica glasses. B. Poumellec1, V.M. Mashinsky2. 1 CNRS LIRA 446 Thermodynamique et Physico-chimie des Materiaux, Universite de Paris Sud, 91405 Orsay... Thermodynamique et Physico-Chimie des matenaux, Bat. 415, UPS Orsay, 91405 Orsay Cedex, France. Tel 33 01 69 15 63 51 Fax 33 01 69 15 48 19 e-mail bp

  11. Aircraft Fire Safety held in Sintra (Portugal) on 22-26 May 1989

    DTIC Science & Technology

    1989-10-01

    OF AN AIRCRAFT PASSENGER CABIN by G.J.Treloar 28 FIRE RESISTANCE AND BREAKDOWN EMISSIONS OF COMPOSITE MATERIALS by K.W.Smith 29 ADVANCED MATERIALS...MATERIALS by A.Te%2rson and R.G.Zalosh 33 METHOD D’EVALUATION DE LA TOXICITE DES PRODUITS DE THERIIOLYSE DES MATERIAUX DE CABINE AVION - ANALYSE DES...extinguishers, additional and more effective hand-held extinguishers, bum-through resistant cargo liners, heat resistant evacuation slides and crew member

  12. Particle Dynamics and Gravel-Bed Adjustments

    DTIC Science & Technology

    1993-05-01

    detecteur des movement des sediments fins. Societe hydrotechnique de France. Transport Hydraulique et Decantation des Materiaux Solides. pp3 9 p. 38...Kirkby, MJ. (Eds.) Channel Ndork Hydrology. Wiley. Chichester. pp 129-173. 67. Lapointe, M.F. (1992) Burst-like sediment suspension events in a sand bed...alluvial sand suspension by eddy correlation. Earth Surface Processes & Landforms, 11, (in press). 69. Soulsby, R.L. (1983) The bottom boundary layer of

  13. Methodes de calcul des forces aerodynamiques pour les etudes des interactions aeroservoelastiques

    NASA Astrophysics Data System (ADS)

    Biskri, Djallel Eddine

    L'aeroservoelasticite est un domaine ou interagissent la structure flexible d'un avion, l'aerodynamique et la commande de vol. De son cote, la commande du vol considere l'avion comme une structure rigide et etudie l'influence du systeme de commande sur la dynamique de vol. Dans cette these, nous avons code trois nouvelles methodes d'approximation de forces aerodynamiques: Moindres carres corriges, Etat minimal corrige et Etats combines. Dans les deux premieres methodes, les erreurs d'approximation entre les forces aerodynamiques approximees par les methodes classiques et celles obtenues par les nouvelles methodes ont les memes formes analytiques que celles des forces aerodynamiques calculees par LS ou MS. Quant a la troisieme methode, celle-ci combine les formulations des forces approximees avec les methodes standards LS et MS. Les vitesses et frequences de battement et les temps d'executions calcules par les nouvelles methodes versus ceux calcules par les methodes classiques ont ete analyses.

  14. Regles de fusion en theorie des champs conformes

    NASA Astrophysics Data System (ADS)

    Begin, Luc

    1999-10-01

    Les théories de champs conformes constituent un domaine de recherche très actif avec de nombreuses applications en physique statistique, en matière condensée, en théorie des cordes, en mathématiques, etc. Nous analysons ici le calcul des règles de fusion dans les modèles Wess- Zumino-Witten par des méthodes positives. Les règles de fusion sont des quantités importantes puisqu'elles indiquent comment se combinent les champs primaires de la théorie. L'approche présentée est basée sur l'hypothèse que les règles de fusion sont décrites par un système d'inéquations linéaire et homogène et mène au concept original de «base de fusion». Cette approche simple et générale permet d'utiliser les méthodes combinatoires et de programmation linéaire pour construire les fonctions génératrices et les bases de fusion. Cette méthode permet d'obtenir des résultats originaux et explicites pour les algèbres su (3), su (4) et sp (4).

  15. Electronic Messaging for the 90s (Les Messageries Electroniques des Annees 90)

    DTIC Science & Technology

    1993-05-01

    cle une importance considdrable, au cette inddpendance support/contenti ntm xiste pas. Au niveati des Etats, des administrations, des entreprises ... financi ~res nature de lVinformation sont tr~s ddpendantes de sa entre detix points tr~s dloignds, tels que New York et chaine de traitement. qui induit tout...principe essenticl de entreprise oti du monde entier. RETRAITABILITE de l’information tout consommateur petit A son tour devenir producteur 1. DES ESPACES

  16. Cue Integration in Dynamic Decision Marking (Integration des indices dans la Prise de Decision Dynamique)

    DTIC Science & Technology

    2010-07-01

    environnements complexes et dynamiques. La nature complexe et dynamique de differents types d’operations (p. ex., les operations basees sur les...destinees a preparer les commandants et le personnel des etats- majors des Forces canadiennes (FC) a prendre des decisions dans des environnements ...Ia prise de decisions dans les environnements complexes et dynamiques est habituellement designee sous le nom de prise de decisions dynamique (POD

  17. Effets de la taille des grains sur les propriétés diélectriques du relaxateur ferroélectrique Pb(Mg{1/3}Nb{2/3})O3

    NASA Astrophysics Data System (ADS)

    Papet, P.

    1994-07-01

    The role of particle and grain size on the dielectric behavior of the perovskite relaxor ferroelectric Pb(Mg{1/3}Nb{2/3})O3 (PMN) were investigated. Ultra-fine powders of PMN were prepared using a reactive calcination process. Reactive calcination, the process by which morphological changes take place upon reaction of the component powders, produced particle agglomerates less than 0.5 μm. Through milling, these structures were readily broken down to nanometric sizes. Sintering, assisted by hot uniaxial pressing, below the temperature of liquid formation of 835 ^{circ}C, allowed the fabrication of highly dense materials with a grain size less than 0.3 μm. The dielectric and related properties were determined for samples having grain sizes in the range of 0.3 μm to 6 μm. Characteristic of relaxors, frequency dependence (K and loss), and point of T_{max} were found to be related to grain and/or particle size and secondarily to the processing conditions. An intrincis-microdomain perturbation concept was proposed to interpret observed scaling effects of the relaxor dielectric behavior in contrast to normally accepted extrinsic grain boundary models. Nous avons étudié les effets de la taille des grains sur les propriétés diélectriques des relaxateurs ferroélectriques Pb(Mg{1/3}Nb{2/3})O3 (PMN). La synthèse de poudres très réactives de PMN a été réalisée par un procédé de calcination réactive. Ce procédé, grâce à des changements morphologiques lors de la réaction des différents composants, permet d'obtenir des particules dont la taille est inférieure à 0,5 μm. Par broyage, ces structures sont facilement désagrégées en des particules de tailles nanométriques. L'utilisation du frittage sous charge uniaxiale en dessous de la température de formation de la phase liquide de 835 ^{circ}C nous a permis de fabriquer des matériaux denses avec une taille de grains inférieure à 0,3 μm. Les propriétés diélectriques ont été déterminées pour

  18. Using Open Captions to Revise Writing in Digital Stories Composed by d/Deaf and Hard of Hearing Students

    ERIC Educational Resources Information Center

    Strassman, Barbara K.; O'Dell, Katie

    2012-01-01

    Using a nonexperimental design, the researchers explored the effect of captioning as part of the writing process of individuals who are d/Deaf and hard of hearing. Sixty-nine d/Deaf and hard of hearing middle school students composed responses to four writing-to-learn activities in a word processor. Two compositions were revised and published with…

  19. A Comparison of Text Structure and Self-Regulated Writing Strategies for Composing from Sources by Middle School Students

    ERIC Educational Resources Information Center

    Reynolds, Gillian A.; Perin, Dolores

    2009-01-01

    This study compared two techniques for teaching middle school students to compose from expository text sources, a common but difficult academic writing task. Classroom social studies content was used. Text structure instruction (TSI), which focused on text characteristics using graphic organizers, was compared with PLAN & WRITE for Summarization…

  20. A Randomized Rounding Approach for Optimization of Test Sheet Composing and Exposure Rate Control in Computer-Assisted Testing

    ERIC Educational Resources Information Center

    Wang, Chu-Fu; Lin, Chih-Lung; Deng, Jien-Han

    2012-01-01

    Testing is an important stage of teaching as it can assist teachers in auditing students' learning results. A good test is able to accurately reflect the capability of a learner. Nowadays, Computer-Assisted Testing (CAT) is greatly improving traditional testing, since computers can automatically and quickly compose a proper test sheet to meet user…

  1. Composing and Performing in the Key Stage 3 Classroom: A Study using Multi-Trait, Multi-Method Analysis

    ERIC Educational Resources Information Center

    Fowler, Andrew

    2014-01-01

    "Music is both a creative and a performing art" (Hallam, 2006, p. 70). Many musicians and music educators maintain that composing and performing, although related, are essentially different aspects of musical activity. In the professional musical sphere, composition and performance are almost invariably separated; academic studies have…

  2. Developing Voice by Composing Haiku: A Social-Expressivist Approach for Teaching Haiku Writing in EFL Contexts

    ERIC Educational Resources Information Center

    Iida, Atsushi

    2010-01-01

    Many educators know that studying and composing literature and poetry helps English learners develop their own voice and sense of audience, and to express important social ideas in the process. Poetry, in particular, offers special challenges, but one type of poem that is manageable for the English as a Foreign Language (EFL) classroom is "haiku,"…

  3. A Note on Using Stratified Alpha to Estimate the Composite Reliability of a Test Composed of Interrelated Nonhomogeneous Items

    ERIC Educational Resources Information Center

    Rae, Gordon

    2007-01-01

    The relationship between stratified alpha (alpha-sub(s)) and the reliability of a test composed of interrelated nonhomogeneous items is examined. It is mathematically demonstrated that when there is congeneric equivalence within the strata or subtests, the difference between the coefficients is a function of the variances of the loadings within…

  4. Netscape Communicator 4.5. Volume II: Beyond the Basics. Advanced Searches, Multimedia, and Composing a Web Page.

    ERIC Educational Resources Information Center

    Gallo, Gail; Wichowski, Chester P.

    This second of two guides on Netscape Communicator 4.5 contains six lessons on advanced searches, multimedia, and composing a World Wide Web page. Lesson 1 is a review of the Navigator window, toolbars, and menus. Lesson 2 covers AltaVista's advanced search tips, searching for information excluding certain text, and advanced and nested Boolean…

  5. Effective Beginning Handwriting Instruction: Multi-Modal, Consistent Format for 2 Years, and Linked to Spelling and Composing

    ERIC Educational Resources Information Center

    Wolf, Beverly; Abbott, Robert D.; Berninger, Virginia W.

    2017-01-01

    In Study 1, the treatment group (N = 33 first graders, M = 6 years 10 months, 16 girls) received Slingerland multi-modal (auditory, visual, tactile, motor through hand, and motor through mouth) manuscript (unjoined) handwriting instruction embedded in systematic spelling, reading, and composing lessons; and the control group (N = 16 first graders,…

  6. Methodology of Artistic Identification on the Path of the Comprehension of Composer's Works in a Piano Class

    ERIC Educational Resources Information Center

    Meleshkina, Elena Anatolyevna; Scherbakova, Anna Iosifovna; Korsakova, Irina Anatolyevna; Slavina, Elena Vladimirovna; Kazakova, Irina Sergeevna

    2016-01-01

    The article is devoted to the reflection on the problem of the "immersion" in the artistic world of a composer's creative work in a piano class in the beginning of the 21st century. The wealth and diversity of the music material for piano players determine the new quality of understanding music and set high goals and objectives for a…

  7. The Impact of Guiding Materials on Students' Conceptual Understanding: The Case of "What Is the Earth's Crust Composed of?

    ERIC Educational Resources Information Center

    Çoruhlu, Tülay Senel; Er Nas, Sibel

    2017-01-01

    The aim of this research is to determine the effect of the use of guidance material based on the 5E model on students' conceptual understanding of a topic entitled "What is the earth's crust composed of?" The sample consists of 40 students from the 5th grade (experimental group 20, control group 20). A concept test, a drawing test, and…

  8. Cultural Diversity: Resources for Music Educators in Selected Works of Three Contemporary African-American Classical Composers

    ERIC Educational Resources Information Center

    Choi, Eunjung; Keith, Laura J.

    2016-01-01

    Contemporary African-American classical composers Cedric Adderley, John Lane, and Trevor Weston intertwine strands of culture and individual experience to produce musical works whose distinct designs offer cultural resources that music educators can use to integrate diversity into instructional settings. Of special interest is their ability to…

  9. Past and Present Intertwining When Learning Is at Stake: Composing and Learning in a Music Theatre Project

    ERIC Educational Resources Information Center

    Mars, Annette

    2016-01-01

    This article presents a study investigating musical learning among 9th grade adolescents in a Swedish lower secondary school. The adolescents collaboratively composed songs for a self-written musical, which they taught to their peers. The purpose of the study was to explore the ways in which adolescents acquire musical knowledge in this specific…

  10. Composing a Narrative Story in a Third Language: Multilinguals' Reliance on Multiple Languages in an L3 Linguistic Task

    ERIC Educational Resources Information Center

    Pap, Emese Boksay

    2016-01-01

    This paper reports on the results of an exploratory study that employed the concurrent think-aloud method to investigate narrative text-creating strategies of multilingual Transylvanian-Hungarians in English, their third language. The study explored the participants' reliance on their different languages as they composed a story in English based…

  11. Body Parts, the Water Cycle, Plants, and Dolphins: Adventures in Primary-Grade Whole-Class Composing

    ERIC Educational Resources Information Center

    Bolden, Benjamin

    2009-01-01

    This article describes the author's personal experiences leading primary grades in whole-class composing. Together they created songs inspired by topics the students were exploring in their homeroom classes. The author systematically describes the songwriting process they employed, identifying specific challenges encountered along the way. The…

  12. Étude expérimentale et modélisation du comportement en compression des structures nid d'abeille

    NASA Astrophysics Data System (ADS)

    Aminanda, Y.; Castanié, B.; Barrau, J. J.; Thévenet, P.; Guedra-Degeorges, D.

    2002-12-01

    Dans le domaine aéronautique les impacts, même de faible énergie, sur des structures sandwichs à âme nid d'abeille posent des problèmes majeurs en terme de résistance résiduelle. La modélisation de l'endom magement dû à l'impact nécessite la connaissance préliminaire du comportement du nid d'abeille en compression. Des essais réalisés en compression quasi-statique uniforme sur des pains de nids d'abeille en différents matériaux (Nomex, Aluminium et Canson) permettent de décomposer la séquence de formation du pli et les facteurs influents. Ces essais tendent à montrer que la force de compression transite essentiellement par les arêtes verticales du nida. Des essais complémentaires sur un motif d'arête confirme cette analyse. La modélisation issue de cette analyse propose, pour connaître la réponse d'une structure nid d'abeille en compression ou indentation, de déterminer la réponse individuelle d'une arête verticale par un essai de compression uniforme. A partir de la loi expérimentale obtenue, la réponse à l'indentation de la structure sandwich est la superposition de la réponse des arêtes pour la forme d'indenteur et la profondeur d'indentation considérée. Une bonne corrélation essais/calcul est obtenue lors d'essais de validation sur nida Nomex avec diverses formes d'indenteurs. La méthode proposée est générale et peut être étendue à divers matériaux cellulaires.

  13. Problemes en enseignement fonctionnel des langues (Problems in the Functional Teaching of Languages). Publication B-103.

    ERIC Educational Resources Information Center

    Alvarez, Gerardo, Ed.; Huot, Diane, Ed.

    Articles include: (1) "L'elaboration du materiel pedagogique pour des publics adultes" (The Elaboration of Teaching Materials for the Adult Public) by G. Painchaud-Leblanc, (2) "L'elaboration d'un programme d'etudes en francais langue seconde a partir des donnees recentes en didactique des langues" (The Elaboration of a Program…

  14. Influence Operations: Historical and Contemporary Dimensions (Les Dimensions Historiques et Contemporaines des Operations d’Influence)

    DTIC Science & Technology

    2007-07-31

    entendue dans l’ensemble du discours politique et militaire des praticiens asiatiques des guerres de petite envergure et des théoriciens soviétiques... dividend ” through a reduction of defence spending. Naturally, the latter would have an effect on the nature of the British defence establishment. The

  15. [And Sarah Félix created "L 'Eau des Fées" and "La Parfumerie des Fées"].

    PubMed

    Raynal, Cécile

    2015-12-01

    century, the parisian perfumery of Sarah Felix was famous especially for her cosmetic "L'Eau des Fées" ("Water of the Fairies"), a dyeing supposed to give back to the old hair the color of their youth. Sarah Felix, sister of the famous actress Rachel, exercised several jobs before becoming perfumer. At first, she was actress, then she tried ... oyster culture in Normandy ! Abandoning these activities, Sarah Felix became really a businesswoman in Paris. She dedicated herself to perfumery, in particular to "L'Eau des Fées", from 1866. To launch its product, she was associated to competency characters (engineer, pharmacist, physician) and benefited from the protection of the imperial family. A lawsuit between the associates and the 1870 war hindered the company's early days, but "L'Eau des Fées" provided with quality pledges, imposed itself definitely. The "Parfumerie des Fées" completed the range of its cosmetics with creams, powders, etc. Sarah Félix paid attention to present "L'Eau des Fées" as a dye devoid of toxicity. Was it really the case and could il be sold nowadays? These two issues are discussed in the last part.

  16. SU-E-T-327: The Update of a XML Composing Tool for TrueBeam Developer Mode

    SciTech Connect

    Yan, Y; Mao, W; Jiang, S

    2014-06-01

    Purpose: To introduce a major upgrade of a novel XML beam composing tool to scientists and engineers who strive to translate certain capabilities of TrueBeam Developer Mode to future clinical benefits of radiation therapy. Methods: TrueBeam Developer Mode provides the users with a test bed for unconventional plans utilizing certain unique features not accessible at the clinical mode. To access the full set of capabilities, a XML beam definition file accommodating all parameters including kV/MV imaging triggers in the plan can be locally loaded at this mode, however it is difficult and laborious to compose one in a text editor. In this study, a stand-along interactive XML beam composing application, TrueBeam TeachMod, was developed on Windows platforms to assist users in making their unique plans in a WYSWYG manner. A conventional plan can be imported in a DICOM RT object as the start of the beam editing process in which trajectories of all axes of a TrueBeam machine can be modified to the intended values at any control point. TeachMod also includes libraries of predefined imaging and treatment procedures to further expedite the process. Results: The TeachMod application is a major of the TeachMod module within DICOManTX. It fully supports TrueBeam 2.0. Trajectories of all axes including all MLC leaves can be graphically rendered and edited as needed. The time for XML beam composing has been reduced to a negligible amount regardless the complexity of the plan. A good understanding of XML language and TrueBeam schema is not required though preferred. Conclusion: Creating XML beams manually in a text editor will be a lengthy error-prone process for sophisticated plans. A XML beam composing tool is highly desirable for R and D activities. It will bridge the gap between scopes of TrueBeam capabilities and their clinical application potentials.

  17. Restauration adaptative des contours par une approche inspiree de la prediction des performances

    NASA Astrophysics Data System (ADS)

    Rousseau, Kami

    En teledetection, les cartes de contours peuvent servir, entre autres choses, a la restitution geometrique, a la recherche d'elements lineaires, ainsi qu'a la segmentation. La creation de ces cartes est faite relativement tot dans la chaine de traitements d'une image. Pour assurer la qualite des operations subsequentes, il faut veiller a obtenir une carte de contours precise. Notre problematique est de savoir s'il est possible de diminuer la perte de temps liee au choix d'algorithme et de parametre en corrigeant automatiquement la carte de contours. Nous concentrerons donc nos efforts sur le developpement d'une methode de detection/restauration de contours adaptative. Notre methode s'inspire d'une technique de prediction des performances d'algorithmes de bas niveau. Elle consiste a integrer un traitement par reseau de neurones a une methode " classique " de detection de contours. Plus precisement, nous proposons de combiner la carte de performances avec la carte de gradient pour permettre des decisions plus exactes. La presente etude a permis de developper un logiciel comprenant un reseau de neurones entraine pour predire la presence de contours. Ce reseau de neurones permet d'ameliorer les decisions de detecteurs de contours, en reduisant le nombre de pixels de fausses alarmes et de contours manques. La premiere etape de ce travail consiste en une methode d'evaluation de performance pour les cartes de contours. Une fois ce choix effectue, il devient possible de comparer les cartes entre elles. Il est donc plus aise de determiner, pour chaque image, la meilleure detection de contours. La revue de la litterature realisee simultanement a permis de faire un choix d'un groupe d'indicateurs prometteurs pour la restauration de contours. Ces derniers ont servi a la calibration et a l'entrainement d'un reseau de neurones pour modeliser les contours. Par la suite, l'information fournie par ce reseau a ete combinee par multiplication arithmetique avec les cartes d

  18. The Riviere des Plante ophiolitic Melange; tectonic setting and melange formation in the Quebec Appalachians

    SciTech Connect

    Cousineau, P.A. )

    1991-01-01

    The Riviere des Plante ophiolitic Melange (RPOM) is the largest and best exposed of the three known ophiolitic melanges that contain blocks of Chain Lakes Massif (CLM). All three lie along the Baie Verte-Brompton line, which marks the suture between the continental rocks of the Humber zone and the oceanic rocks of the Dunnage zone. The ophiolitic melange is composed of: serpentinized ultramafic rocks, some of which are sheared and/or carbonatized; blocks of amphibolitized gabbro; basalt; volcanogenic breccia; and conglomerates. It also contains continental K-rich granitoid rocks and high-grade metamorphic (upper amphibolite facies) rocks. The RPOM is part of the Saint-Daniel Melange, an accretionary prism onto which the RPOM has been tectonically emplaced. The CLM was part of a terrane accreted to the Laurentian margin during the Taconian orogeny. Blocks of the CLM along the Baie Verte-Brompton line are interpreted as fragments of this terrane caught within the suture zone. It is proposed that the CLM could be the equivalent of Grenville-derived greywacke originally laid down during the phase of continental rifting that led to the formation of the Iapetus Ocean and was later tectonized and metamorphosed during the Taconian and Acadian orogenies. The RPOM would represent the relic of a serpentinite diapir that rose within a deep oceanic fault. The presence of continental rocks like the CLM suggest that a continental magmatic arc was put in contact with an oceanic crust along this fault.

  19. Cognitive Task Analysis (l’Analyse des taches cognitives)

    DTIC Science & Technology

    2000-10-01

    pilotage, guidage, gestion de produits chimiques), aujourd’hui, le CTA est principalement utilisé pour des tâches décisionnelles telles que le...adéquation entre les fonctions système et les capacités cognitives humaines (2) optimisation des performances système et de la charge de travail (3...S.E. DGA Etas Division Facteurs Humains Professor Emeritus Cognitive & Neural S&T Division BP 36 Route de Laval The University of Warwick Office of

  20. Comparison des donnees simulees des capteurs de SPOT et landsat-D: Application a une region agricole

    NASA Astrophysics Data System (ADS)

    Saint, Gilbert; Podaire, Alain

    La modélisation de la luminance spectrale des objets observés en télédétection permet d'effectuer des simulations de différents capteurs à partir de données obtenues au moyen d'un scanneur DAEDALUS aéroporté : les qualités radiométrique et géométrique ont pu être évaluées par une comparaison avec des données Landsat réelles. L'analyse sur une zone agricole met surtout en évidence le rôle important de l'accroissement de la résolution.