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Sample records for des modifications post-traductionelles

  1. Étude des modifications structurales de l'eau confinée dans le gel de silice

    NASA Astrophysics Data System (ADS)

    Fouzri, A.; Dorbez-Sridi, R.; Oumezzine, M.

    2004-11-01

    Les modifications structurales de l'eau confinée dans le gel de silice en poudre en fonction du taux d'hydratation sont étudiées par calorimétrie différentielle à balayage et par diffusion des rayons X. L'analyse thermique par DSC a permis de montrer que pour les faibles taux d'hydratation (≤ 50%) l'eau est complètement confinée dans les pores alors que pour les forts taux d'hydratation (>50%) l'eau se trouve aussi bien dans les pores qu'autour des grains de la silice. L'apparition de la glace cubique lors du refroidissement de l'eau confinée dans le gel de silice prouve que l'interaction eau-silice ne peut être négligée lors de la détermination du signal de l'eau. L'extraction du signal, diffusé uniquement par l'eau confinée, à partir des intensités diffusées par le gel de silice à deux taux d'hydratation distincts, révèle dans les fonctions de corrélation de paire un pic à 3.7Å qui ne peut être attribué qu'à une corrélation oxygène-oxygène inexistante dans l'eau massique et résultant de la déformation du réseau tétraédrique des molécules d'eau sous l'effet du confinement et de la proximité d'une surface.

  2. MODIFICATIONS ULTRASTRUCTURALES DES CELLULES SÉCRÉTRICES DE LA GLANDE PROTHORACIQUE DE VERS À SOIE AU COURS DES DEUX DERNIERS ÂGES LARVAIRES

    PubMed Central

    Beaulaton, J. A.

    1968-01-01

    Ultrastructural study of the prothoracic glands of silkworms (Antheraea pernyi and Bombyx mori) at the last two larval stages has shown that the essential modifications which take place during each intermolt affect the chondriome of secretory cells. A description is given of the differentiation of macromitochondria from typical mitochondria by a general swelling, a clearing of the matrix, and the formation of a complex tubular network. The hypothesis of fixation or anaesthesia artifacts has been dismissed because of the persistence of these transformations after different fixations and because of the existence of numerous intermediary stages between these two types of chondriosomes which imply the progressiveness of differentiation. The cytochemical demonstration of mitochondrial DNA fibers suggests that the genetic information, probably present in this type of nucleic acid, controls the differentiation and the specific metabolic activity of these organelles. The frequent relationships observed in Antheraea between the tubules of agranular reticulum and the macromitochondria which are reminiscent of the vacuoles-mitochondria associations of the adrenal cortex, may be related to the transfer of cholesterol and other precursors of steroidogenesis. In the last stages, the macromitochondria become transformed into vacuoles by a disappearance of the tubular network. The correlation revealed between mitochondrial transformations and the cyclical release of ecdysone (65) leads to the conclusion that a prominent fraction of chondriosomes is involved, in relation to the agranular reticulum, in the elaboration of steroid hormones such as ecdysone. PMID:5699930

  3. Modification et caractérisation de la surface de fibres de verre pour son insertion postérieure dans des matériaux cimentaires

    NASA Astrophysics Data System (ADS)

    Bismarck, A.; Ajuriagojeaskoa, E. E.; Springer, J.; Habel, W. R.

    1999-07-01

    Optical fibres are widely used as physical and mechanical sensors in various matrices. Those commercial available fibres are mostly coated with different polymers (e.g. polyimide). The problem of using such coatings is the undefined adhesion and the stress transmission from the matrix material into the fibre as well as the alkaline attack from the cementitious environments onto the glass surface. Therefore the known silanisation process with alkylsilanes for surface modification was studied. To achieve a silane film onto the fibre surface as close as possible a fibre pre-treatment in oxygen plasma was applied. The wetting behaviour of the oxygen plasma treated fibres as well as the silanized fibres were studied using the Wilhelmy-method. The influence of the silane concentration and the time of the pre-treatment on the wetting properties was investigated. By scanning electron microscopy, changes of the surface morphology were detected. Additionally, the mechanical properties of the oxygen plasma treated fibres, and silanized fibres exposed to a highly alkaline pore solution were measured. For selected fibre samples (decoated and untreated as well as silanized fibres) the adhesion to a concrete matrix was studied using the indention test. Les fibres optiques sont de plus en plus utilisées comme capteurs des propriétés physiques et mécaniques de nombreuses matrices. Ces fibres commerciales sont généralement enrobées avec différents polymères (par exemple polyimide). Les problèmes dus à l'enrobage des fibres optiques sont une adhésion et une transmission de charge de la matrice du béton à la fibre non définies. Un autre problème majeur est l'alcalinité du béton et son influence sur la surface de la fibre. Nous avons utilisé le procédé de silanisation. Pour obtenir un film de silane le plus homogène possible sur la surface, les fibres sont pré-traitées par le plasma d?oxygène. Le mouillage de fibres traitées par le plasma d?oxygène, ainsi que

  4. 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.

  5. 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…

  6. Behavior modification.

    PubMed

    Pelham, W E; Fabiano, G A

    2000-07-01

    Attention deficit/hyperactivity disorder (ADHD) is a chronic and substantially impairing disorder. This means that treatment must also be chronic and substantial. Behavior Modification, and in many cases, the combination of behavior modification and stimulant medication, is a valid, useful treatment for reducing the pervasive impairment experienced by children with ADHD. Based on the research evidence reviewed, behavior modification should be the first line of treatment for children with ADHD.

  7. Home Modification

    MedlinePlus

    ... it is important to consider certain safety modifications. Adaptations such as those in the following list can ... The importance of a Consumer Perspective in Home Adaptation of Alzheimer’s Households” (Chapter 6 pp 91-112) ...

  8. Ubiquitin modifications

    PubMed Central

    Swatek, Kirby N; Komander, David

    2016-01-01

    Protein ubiquitination is a dynamic multifaceted post-translational modification involved in nearly all aspects of eukaryotic biology. Once attached to a substrate, the 76-amino acid protein ubiquitin is subjected to further modifications, creating a multitude of distinct signals with distinct cellular outcomes, referred to as the 'ubiquitin code'. Ubiquitin can be ubiquitinated on seven lysine (Lys) residues or on the N-terminus, leading to polyubiquitin chains that can encompass complex topologies. Alternatively or in addition, ubiquitin Lys residues can be modified by ubiquitin-like molecules (such as SUMO or NEDD8). Finally, ubiquitin can also be acetylated on Lys, or phosphorylated on Ser, Thr or Tyr residues, and each modification has the potential to dramatically alter the signaling outcome. While the number of distinctly modified ubiquitin species in cells is mind-boggling, much progress has been made to characterize the roles of distinct ubiquitin modifications, and many enzymes and receptors have been identified that create, recognize or remove these ubiquitin modifications. We here provide an overview of the various ubiquitin modifications present in cells, and highlight recent progress on ubiquitin chain biology. We then discuss the recent findings in the field of ubiquitin acetylation and phosphorylation, with a focus on Ser65-phosphorylation and its role in mitophagy and Parkin activation. PMID:27012465

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Behavior Modification in Coaching.

    ERIC Educational Resources Information Center

    Lynch, Annette Rutt; Stillman, Stephen M.

    1979-01-01

    An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

  14. Behavior Modification is not...

    ERIC Educational Resources Information Center

    Tawney, James W.; And Others

    1973-01-01

    Identified are misconceptions of behavior modification procedures according to which behavior modification is connected mistakenly with noncontingent reinforcement, partial change of a teacher's behavior, decelerations of inappropriate behaviors only, dependency producing technology, teacher dominated activity, a single type of classroom…

  15. Readers of histone modifications

    PubMed Central

    Yun, Miyong; Wu, Jun; Workman, Jerry L; Li, Bing

    2011-01-01

    Histone modifications not only play important roles in regulating chromatin structure and nuclear processes but also can be passed to daughter cells as epigenetic marks. Accumulating evidence suggests that the key function of histone modifications is to signal for recruitment or activity of downstream effectors. Here, we discuss the latest discovery of histone-modification readers and how the modification language is interpreted. PMID:21423274

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Basic Behavior Modification.

    ERIC Educational Resources Information Center

    Mehrabian, Albert

    This monograph examines the component parts of behavior modification, initially defining the problem behavior and drawing a difference between specific observable behaviors (the focus of behavior modification), and the interest of Freudian and similar psychologies in unobservable internal processes. Instrumental learning related to shaping in…

  1. Permit application modifications

    SciTech Connect

    1995-11-01

    This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

  2. 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.

  3. Modification by chloramphenicol of diethyl sulphate-induced male recombination frequency in Drosophila melanogaster.

    PubMed

    Miglani, G S; Kaur, N P

    1995-06-01

    To study the effect of chloramphenicol (CPL, an inhibitor of protein synthesis) on diethyl sulphate (DES, a potent mutagen) induced male recombination frequency, the F1 (+/aristaless dumpy black cinnabar, al dp b cn) larvae of D. melanogaster were given a pre- or post-treatment of CPL with DES during the first or second half of larval life. In order to determine sensitivity of different germ cell stages to the induction and modification of male recombination frequency, five 3-day broods were taken from every F1 male. DES showed toxic effect on egg-to-adult development. DES was found to be a potent recombinogen. Several cases of non-reciprocal male recombination were recorded. The most frequent recombinant phenotype observed was b cn followed by cn and al. Majority of the recombinants appeared in clusters suggesting their pre-meiotic origin. DES produced male recombination at a stage where only primary spermatocytes were present in the larval testes. CPL when given as a pre- or post-treatment with DES revealed highest frequency of male recombination in broods that represented effect of treatment on spermatogonia predominantly. CPL enhanced the overall level of male recombination produced by DES in both pre- and post-treatments. The results suggested the role of protein synthesis in induction of male recombination in D. melanogaster. In addition, the present experiments give a methodology of enhancing the frequency of chemically-induced male recombination.

  4. Gestion des ressources hydriques adaptee aux changements climatiques pour la production optimale d'hydroelectricite. Etude de cas: Bassin versant de la riviere Manicouagan

    NASA Astrophysics Data System (ADS)

    Haguma, Didier

    deversements non productibles dans le climat futur. Des strategies d'adaptation structurale ont ete analysees pour augmenter la capacite de production et la capacite d'ecoulement de certaines centrales hydroelectriques afin d'ameliorer la performance du systeme. Une analyse economique a permis de choisir les meilleures mesures d'adaptation et de determiner le moment opportun pour la mise en oeuvre de ces mesures. Les resultats de la recherche offrent aux gestionnaires des systemes hydriques un outil qui permet de mieux anticiper les consequences des changements climatiques sur la production hydroelectrique, incluant le rendement de centrales, les deversements non productibles et le moment le plus opportun pour inclure des modifications aux systemes hydriques. Mots-cles : systemes hydriques, adaptation aux changements climatiques, riviere Manicouagan

  5. Enzymatic modification of schizophyllan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An enzymatic method was developed for the progressive modification of the polysaccharide schizophyllan. Fungal strains Hypocrea nigricans NRRL 62555, Penicillium crustosum NRRL 62558, and Penicillium simplicissimum NRRL 62550 were previously identified as novel sources of ß-endoglucanase with specif...

  6. 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

  7. Human Rights and Behavior Modification

    ERIC Educational Resources Information Center

    Roos, Philip

    1974-01-01

    Criticisms of behavior modification, which charge that it violates ethical and legal principles, are discussed and reasons are presented to explain behavior modification's susceptibility to attack. (GW)

  8. 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

  9. 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.

  10. Readers of PCNA modifications.

    PubMed

    Ulrich, Helle D; Takahashi, Tomio

    2013-08-01

    The eukaryotic sliding clamp, proliferating cell nuclear antigen (PCNA), acts as a central coordinator of DNA transactions by providing a multivalent interaction surface for factors involved in DNA replication, repair, chromatin dynamics and cell cycle regulation. Posttranslational modifications (PTMs), such as mono- and polyubiquitylation, sumoylation, phosphorylation and acetylation, further expand the repertoire of PCNA's binding partners. These modifications affect PCNA's activity in the bypass of lesions during DNA replication, the regulation of alternative damage processing pathways such as homologous recombination and DNA interstrand cross-link repair, or impact on the stability of PCNA itself. In this review, we summarise our current knowledge about how the PTMs are "read" by downstream effector proteins that mediate the appropriate action. Given the variety of interaction partners responding to PCNA's modified forms, the ensemble of PCNA modifications serves as an instructive model for the study of biological signalling through PTMs in general.

  11. Programming for articularion modification.

    PubMed

    Gerber, A

    1977-02-01

    Within the past decade, principles and techniques of programmed instruction have been applied to the procedures of articulation modification in a number of preconstructed programs. The analysis of nine of these programs reveals that the majority of them are characterized by precisely stated objectives, ordered sequences of materials and procedures, clearly established criteria and rigorously controlled methods of reinforcement and recording of responses. Evaluation of the preconstructed programs raises some questions about the appropriateness of certain aspects of the technology to the process of articulation modification.

  12. Superposition tridimensionnelle (3-D) sur la base du crâne pour l’évaluation longitudinale des effets de la croissance et du traitement

    PubMed Central

    Cevidanes, Lucia H.S.; Styner, Martin; Proffit, William R.; Ngom, Traduit par Papa Ibrahima

    2010-01-01

    RÉSUMÉ – Pour évaluer les modifications liées à la croissance ou au traitement, il est nécessaire de superposer les céphalogrammes successifs sur une structure stable. En céphalométrie bidimensionnelle (2-D), la base du crâne est souvent utilisée pour les superpositions parce que les changements qu’elle subit après le développement cérébral sont mineurs. Toutefois, sur les céphalogrammes de profil et de face, les points de repère basicraniens sont peu fiables. Dans cet article, nous présentons une nouvelle méthode de superposition tridimensionnelle (3-D) basée sur un enregistrement entièrement automatisé des intensités de voxels, au niveau de la surface de la base du crâne. Le progiciel utilisé permet l’évaluation quantitative des modifications qui apparaissent dans le temps, grâce au calcul de la distance euclidienne entre les surfaces du modèle tridimensionnel. Il permet également l’appréciation visuelle de l’emplacement et de l’importance des modifications au niveau des maxillaires, grâce à une surimpression graphique. Les modifications sont visualisées par comparaison à des tables de correspondance de couleur. On peut ainsi réaliser une étude détaillée des modes d’adaptation chez les patients dont la croissance et/ou le traitement ont provoqué des modifications squelettiques cliniquement significatives. PMID:19954732

  13. 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.

  14. 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).

  15. 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).

  16. 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).

  17. 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).

  18. 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).

  19. 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).

  20. 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).

  1. 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).

  2. 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).

  3. 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).

  4. 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).

  5. 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).

  6. Instructional Improvement: Behavior Modification.

    ERIC Educational Resources Information Center

    Haring, Norris G.; Hayden, Alice H.

    Sixteen papers are provided. B. F. Skinner discusses the arrangement of contingencies for learning: Lloyd Homme describes behavioral engineering; and Frank Hewett considers behavior modification in special education. Also treated are experimental education by Norris Haring, program evaluation by Arthur Lumsdaine, and administration of special…

  7. Behavior Modification with Children

    ERIC Educational Resources Information Center

    Brown, Daniel G.

    1972-01-01

    The author urges wider use of positive reinforcement theories in helping emotionally disturbed and mentally handicapped children. Underlining the influence of environment on behavior, he also notes that behavior modification programs utilize fewer trained personnel more effectively and, like Tennessee's Re-Education Treatment, allow for therapy in…

  8. THE MODIFICATION OF STUTTERING.

    ERIC Educational Resources Information Center

    BRUTTEN, EUGENE J.; SHOEMAKER, DONALD J.

    INTENDED FOR BOTH THE COLLEGE STUDENT AND THE PROFESSIONAL SPEECH PATHOLOGIST, THE BOOK PRESENTS CURRENT LEARNING THEORIES CONCERNING STUTTERING, DATA IMPORTANT TO THE THEORIES, AND A 2-PROCESS THEORY OF LEARNING FOR THEORETICAL INTEGRATION OF THE DATA ON STUTTERING AND FOR THERAPEUTIC MODIFICATION. INFORMATION PRESENTED ABOUT BEHAVIORISTIC…

  9. Toy Modification Note. Revised.

    ERIC Educational Resources Information Center

    Vanderheiden, Gregg C.; And Others

    Described are toy modifications which enable handicapped individuals to operate battery-powered toys. A battery interrupter is explained as a device which fits between the batteries in a toy and provides the ability to have a separate on-off switch which can be custom designed to fit a handicapped user's needs. Construction and use of three types…

  10. Biblical behavior modification.

    PubMed

    Lasure, L C; Mikulas, W L

    1996-07-01

    Although we may have formalized and systematized the field of behavior modification in the last few decades, people around the world have been using behavioral change strategies throughout history. Premack's (1965) theory of reinforcement is often called "Grandma's rule" because grandmothers have long been using it (e.g. You must finish your vegetables before you may go out and play). Franks (1969, p. 4), in one of the first behavioral texts, gave historical examples from China, Turkey, France, and Italy. Knapp and Shodahl (1974) showed how Benjamin Franklin used behavior modification. And de Silva (1984, 1985) gave examples of behavior modification by the Buddha and other early Buddhists. Conspicuously absent from our literature are examples from the Judeo-Christian tradition. In this paper, we provide a number of behavior modification examples from the Bible (New International Version). Footnotes provide references for many more examples. In the discussion, we explore implications for education and therapy. Examples are grouped by the following categories: operant conditioning, respondent conditioning, modeling, and cognitive interventions. However, the Biblical examples, like contemporary case studies, do not always fall neatly into discrete categories. They often are a combination, particularly operant and respondent conditioning interweaving.

  11. Diet Modification for Hyperlipidemia

    PubMed Central

    Mann, Heather D.; Piotrowski, Pamela

    1992-01-01

    Hyperlipidemia is a major risk factor associated with cardiovascular disease. Dietary modification is effective in achieving and maintaining improved serum lipid levels. Nutritional care provided by a dietitian includes individual dietary and lifestyle assessment, formulating an appropriate dietary regimen, education, and follow-up assessments. PMID:21221406

  12. Posttranslational protein modification in Archaea.

    PubMed

    Eichler, Jerry; Adams, Michael W W

    2005-09-01

    One of the first hurdles to be negotiated in the postgenomic era involves the description of the entire protein content of the cell, the proteome. Such efforts are presently complicated by the various posttranslational modifications that proteins can experience, including glycosylation, lipid attachment, phosphorylation, methylation, disulfide bond formation, and proteolytic cleavage. Whereas these and other posttranslational protein modifications have been well characterized in Eucarya and Bacteria, posttranslational modification in Archaea has received far less attention. Although archaeal proteins can undergo posttranslational modifications reminiscent of what their eucaryal and bacterial counterparts experience, examination of archaeal posttranslational modification often reveals aspects not previously observed in the other two domains of life. In some cases, posttranslational modification allows a protein to survive the extreme conditions often encountered by Archaea. The various posttranslational modifications experienced by archaeal proteins, the molecular steps leading to these modifications, and the role played by posttranslational modification in Archaea form the focus of this review.

  13. Posttranslational Protein Modification in Archaea

    PubMed Central

    Eichler, Jerry; Adams, Michael W. W.

    2005-01-01

    One of the first hurdles to be negotiated in the postgenomic era involves the description of the entire protein content of the cell, the proteome. Such efforts are presently complicated by the various posttranslational modifications that proteins can experience, including glycosylation, lipid attachment, phosphorylation, methylation, disulfide bond formation, and proteolytic cleavage. Whereas these and other posttranslational protein modifications have been well characterized in Eucarya and Bacteria, posttranslational modification in Archaea has received far less attention. Although archaeal proteins can undergo posttranslational modifications reminiscent of what their eucaryal and bacterial counterparts experience, examination of archaeal posttranslational modification often reveals aspects not previously observed in the other two domains of life. In some cases, posttranslational modification allows a protein to survive the extreme conditions often encountered by Archaea. The various posttranslational modifications experienced by archaeal proteins, the molecular steps leading to these modifications, and the role played by posttranslational modification in Archaea form the focus of this review. PMID:16148304

  14. 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…

  15. Effet des Plastifiants sur la Temperature de Transition Vitreuse, Tg, du Butadiene a Terminaison Hydroxy et du Polyazoture de Glycidyle - Simulations et Experiences (Effect of the Plasticizers on the Vitreous Transition Temperature, Tg, of the Butadiene to Termination Hydroxy and the Polyazoture of Glycidyle - Simulations and Experiences)

    DTIC Science & Technology

    2008-09-01

    certaines variables lors des analyses et, ainsi, creer des ensembles thermodynamiques distincts. Le plus courant est l’ensemble NVE, pour lequel le... thermodynamiques imposent des modifications a diverses proprietes, notamment la temperature de fusion — une transition du premier ordre. La transition...certains, la transition vitreuse est presentee comme un phenomene thermodynamique [9]; dans d’autres comme un processus cinetique [10]. Le modele du

  16. 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.

  17. 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

  18. Pectin modifications: a review.

    PubMed

    Chen, Jun; Liu, Wei; Liu, Cheng-Mei; Li, Ti; Liang, Rui-Hong; Luo, Shun-Jing

    2015-01-01

    In recent years, the interest in studying modification of pectin has increased. A number of hydroxyl and carboxyl groups distributed along the backbone as well as a certain amount of neutral sugars presented as side chains make pectin capable of preparing a broad spectrum of derivatives. By forming pectin derivatives, their properties may be modified and some other new functional properties may be created. This article attempts to review the information about various methods used for pectin modification, including substitution (alkylation, amidation, quaternization, thiolation, sulfation, oxidation, etc.), chain elongation (cross-linking and grafting) and depolymerization (chemical, physical, and enzymatic degradation). Characteristics and applications of some pectin derivatives are also presented. In addition, the safety and regulatory status of pectin and its derivatives were reviewed.

  19. Response modification in carcinogenesis.

    PubMed Central

    Cerutti, P A

    1989-01-01

    A major goal in multistep carcinogenesis research is the integration of recent findings obtained by sophisticated molecular-genetic and cytogenetic analysis of cancer into the more descriptive concepts of experimental pathology. It is proposed that the creation of a promotable cell in carcinogenic initiation requires a response modification to extracellular or intercellular signals. Different types of response modification can be distinguished: changes in the receptors for growth and differentiation factors and their cytoplasmic and nuclear signal transduction pathways; increased resistance of initiated cells to cytotoxic agents; alterations in junctional cell-to-cell communications. The challenge of a response-modified cell to an appropriate promoter results in its selection and clonal expansion, usually to a benign tumor. In addition, for malignancy, chromosomal changes are required that affect cellular functions that can play a role early or late in tumorigenesis. These concepts are illustrated with examples from oncogene research and oxidant promotion. PMID:2667983

  20. Clinical risk modification.

    PubMed

    Wilson, J

    Claims for compensation in cases of clinical negligence have risen dramatically in recent years. The implementation of the NHS reforms, with greater clarity of roles and responsibilities and the emphasis on devolving decision-making as close to the patient as possible, is meant to affect the entire performance of healthcare delivery. For most senior managers and clinicians, the environment in which they operate has grown increasingly turbulent and complex. Both purchasers and providers of health care want the best and most effective and efficient care. The cost and quality of care are components in determining the value of health care delivered, and both are elements of healthcare risk. To begin to manage these elements of risk, the process of healthcare risk modification can be applied. Healthcare risk modification provides the best service for patients through obtaining a synergy between risk management, quality and the law.

  1. 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

  2. Oxidative DNA modifications.

    PubMed

    Poulsen, Henrik E

    2005-07-01

    Oxidative DNA modifications are frequent in mammalian DNA and have been suggested an important mechanism in carcinogenesis, diabetes and ageing. The foundations for this suggestion are: Evidence for the importance of oxidative DNA modifications in cancer development is: high levels of oxidative lesions in cancer tissue; highly conserved and specific DNA repair systems targeting oxidative lesions; high levels of oxidative DNA lesions in oxidative DNA repair knock-out animals; defective repair of oxidative lesions in cancer-prone progeria syndromes; reduced cancer incidence in populations with high dietary antioxidant intake; and increased oxidative stress to DNA in tobacco smokers. Conflicting evidence for a relation between oxidative stress to DNA and cancer is: disagreement about the true levels and occurrence of the oxidative lesions in vivo; failure to identify the localization of oxidative lesions in important genes, e.g. tumor suppressor and oncogenes; lack of evidence that the oxidative lesions induce mutations in vivo; no cancer development in animals knocked-out for specific DNA repair enzymes in spite of high tissue levels of oxidative lesions; and unchanged cancer rates after antioxidant interventions in large clinical controlled and randomized trials. The rate of DNA oxidation has been estimated from urinary excretion of repair products and it is evident that if these lesions were not repaired, a large part of DNA would be oxidized to a degree not compatible with living. The methodologies by which oxidative DNA modifications are measured cover a wide and different range, advantages and disadvantages will be presented. One particular problem is artificial oxidation, and methods to prevent such artifacts will be presented together with results from a large interlaboratory standardization program. The methodology by which the lesions can be measured is complicated and prone to artifacts during DNA isolation, digestion, derivatization and maybe even during

  3. Genetic modification and genetic determinism.

    PubMed

    Resnik, David B; Vorhaus, Daniel B

    2006-06-26

    In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions.

  4. Genetic modification and genetic determinism

    PubMed Central

    Resnik, David B; Vorhaus, Daniel B

    2006-01-01

    In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

  5. 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.

  6. Dual modification of biomolecules.

    PubMed

    Maruani, Antoine; Richards, Daniel A; Chudasama, Vijay

    2016-07-14

    With the advent of novel bioorthogonal reactions and "click" chemistry, an increasing number of strategies for the single labelling of proteins and oligonucleotides have emerged. Whilst several methods exist for the site-selective introduction of a single chemical moiety, site-selective and bioorthogonal dual modification of biomolecules remains a challenge. The introduction of multiple modules enables a plethora of permutations and combinations and can generate a variety of bioconjuguates with many potential applications. From de novo approaches on oligomers to the post-translational functionalisation of proteins, this review will highlight the main strategies to dually modify biomolecules.

  7. Soviet ionospheric modification research

    SciTech Connect

    Duncan, L.M.; Carlson, H.C.; Djuth, F.T.; Fejer, J.A.; Gerson, N.C.; Hagfors, T.; Newman, D.B. Jr.; Showen, R.L.

    1988-07-01

    Soviet published literature in ionospheric modification research by high-power radio waves is assessed, including an evaluation of its impact on and applications to future remote-sensing and telecommunications systems. This assessment is organized to place equal emphasis on basic research activities, designed to investigate both the natural geophysical environment and fundamental plasma physics; advanced research programs, such as those studying artificial ionization processes and oblique high-power radio propagation and practical system applications and operational limitations addressed by this research. The assessment indicates that the Soviet Union sustains high-quality theoretical and experimental research programs in ionospheric modification, with a breadth and level of effort greatly exceeding comparable Western programs. Soviet theoretical research tends to be analytical and intuitive, as compared to the Western emphasis on numerical simulation techniques. The Soviet experimental approach is less exploratory, designed principally to confirm theoretical predictions. Although limited by inferior diagnostic capabilities, Soviet experimental facilities are more numerous, operate on a more regular basis, and transmit radio wave powers exceeding those os Western facilities. Because of its broad scope of activity, the Soviet Union is better poised to quickly exploit new technologies and system applications as they are developed. This panel has identified several key areas of Soviet research activity and emerging technology that may offer long-term opportunities for remote-sensing and telecommunications advantages. However, we have found no results that suggest imminent breakthrough discoveries in these fields.

  8. 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.

  9. 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

  10. Vers l'elimination des dessins d'ingenierie des processus de modification d'ingenierie en aeronautique

    NASA Astrophysics Data System (ADS)

    Quintana, Virgilio

    For many years, 3D models and 2D drawings have been the main basic elements that together form and carry a product's definition throughout its lifecycle. With the advent of the Digital Product Definition trend, the Aerospace and Automotive industries have been very interested in adopting a Model-based Definition (MBD) approach that promises reduced time-to-market and improved product quality. Its main purpose is to improve and accelerate the design, manufacturing and inspection processes by integrating drawing annotations directly onto a 3D model, thereby minimizing the need to generate engineering drawings. Even though CAD tools and international standards support the MBD concept, its implementation throughout the whole product lifecycle has not yet been fully adopted; traditional engineering drawings still play an essential part in the capture and distribution of non-geometric data (tolerances, notes, etc.), in the long-term storage of product definitions, as well as in the management of engineering changes. This is especially so within the Engineering Change Management (ECM) process, which involves the study, review, annotation, validation, approval and release of engineering drawings. The exploration of alternatives to reengineer the ECM process in the absence of drawings is therefore a necessary step before the MBD approach can be broadly accepted. The objective of this research project was to propose a solution to conduct the ECM process in a drawing-less environment and to quantify its potential gains. Two Canadian aerospace companies participated in this project. First, the main barriers to be overcome in order to fully implement the MBD initiative were identified. Our observations were based on forty-one interviews conducted within the Engineering, Drafting, Configuration Management, Airworthiness, Certification, Manufacturing, Inspection and Knowledge Management departments from the two participating companies. The results indicated that there is a need to define how the Product Definition will be carried in this drawing-less environment while supporting all of the downstream users' specific requirements. Next, a solution to conduct an MBD-driven Engineering Change Management Process (ECM) was developed and evaluated based on the process requirements from both companies. The solution consists of the definition of a dataset composed of the MBD model (generated by the CAD system) and a lightweight distribution file (generated and exploited by the visualization application). The ECM process was then reengineered to support its execution when working with MBD datasets. Finally, the gains from administering the MBD-driven ECM process were determined using empirical and experimental data within a discrete-event simulation approach. Based on a case study conducted in a Canadian aerospace company, our results show that a reduction of about 11% can be achieved in both the average overall processing time and in the average cost.

  11. Artificial modification meeting reminder

    NASA Astrophysics Data System (ADS)

    Gordon, W. E.

    A symposium on artificial modification of the ionosphere by high-powered radio waves (V. V. Migulin, Honorary Chairman) will be held September 19-23, 1988, at the Scandic Hotel, Tromso, Norway. The symposium, sponsored by Union Radio Scientifique Internationale Commissions (URSI) G and H, is in the URSI series which started at Suzdal in 1983. Information on the scientific program is available from V.V. Migulin, U.S.S.R. Academy of Sciences, 103907, Moscow Center, Marx Avl8, U.S.S.R.; Peter Stubbe, Max- Planck-Institut fuer Aeronomy, D-3411 Katlenburg- Lindau 3, Federal Republic of Germany; or W.E. Gordon, Rice University, Space Physics and Astronomy Dept., Houston, TX 77251. For local arrangements information, contact Asgeir Brekke, Institute Matematisk Realfag, Aurora Observatory, Box 953, N-9001, Tromso, Norway.

  12. Public perceptions of hurricane modification.

    PubMed

    Klima, Kelly; Bruine de Bruin, Wändi; Morgan, M Granger; Grossmann, Iris

    2012-07-01

    If hurricane modification were to become a feasible strategy for potentially reducing hurricane damages, it would likely generate public discourse about whether to support its implementation. To facilitate an informed and constructive discourse, policymakers need to understand how people perceive hurricane modification. Here, we examine Florida residents' perceptions of hurricane modification techniques that aim to alter path and wind speed. Following the mental models approach, we conducted a survey study about public perceptions of hurricane modification that was guided by formative interviews on the topic. We report a set of four primary findings. First, hurricane modification was perceived as a relatively ineffective strategy for damage reduction, compared to other strategies for damage reduction. Second, hurricane modification was expected to lead to changes in projected hurricane path, but not necessarily to the successful reduction of projected hurricane strength. Third, more anger was evoked when a hurricane was described as having changed from the initially forecasted path or strength after an attempted modification. Fourth, unlike what we expected, participants who more strongly agreed with statements that recognized the uncertainty inherent in forecasts reported more rather than less anger at scientists across hurricane modification scenarios. If the efficacy of intensity-reduction techniques can be increased, people may be willing to support hurricane modification. However, such an effort would need to be combined with open and honest communications to members of the general public.

  13. HMG Modifications and Nuclear Function

    PubMed Central

    Zhang, Qingchun; Wang, Yinsheng

    2009-01-01

    High mobility group (HMG) proteins assume important roles in regulating chromatin dynamics, transcriptional activities of genes and other cellular processes. Post-translational modifications of HMG proteins can alter their interactions with DNA and proteins, and consequently, affect their biological activities. Although the mechanisms through which these modifications are involved in regulating biological processes in different cellular contexts are not fully understood, new insights into these modification “codes” have emerged from the increasing appreciation of the functions of these proteins. In this review, we focus on the chemical modifications of mammalian HMG proteins and highlight their roles in nuclear functions. PMID:20123066

  14. La Station Laser ultra mobile: de l'Obtention d'une Exactitude centimétrique des Mesures à des Applications en Océanographie et Géodésie Spatiales

    NASA Astrophysics Data System (ADS)

    Nicolas, Joëlle

    2000-12-01

    La Station Laser Ultra Mobile est la plus petite station de télémétrie laser au monde, ne pesant que 300 kg, dédiée à la poursuite de satellites équipés de rétroréflecteurs laser. Elle utilise un petit télescope de 13 cm de diamètre placé sur une monture issue d'un théodolite de précision et motorisé, un laser très compact et une photodiode à avalanche permettant la détection au niveau du simple photo-électron. Les premières expériences (Corse, fin 1996) ont révélé de nombreuses instabilités dans la qualité des mesures. Ce travail concerne l'étude et la mise en place de nombreuses modifications techniques afin d'atteindre une exactitude centimétrique des mesures et de pouvoir participer à la campagne de validation des orbites et d'étalonnage de l'altimètre du satellite océanographique JASON-1 (2001). La précision instrumentale souhaitée a été vérifiée avec succès en laboratoire. Outre cet aspect instrumental et métrologique, une analyse a été développée afin de pouvoir estimer l'exactitude et la stabilité des observations de la station mobile après intégration des modifications. A partir d'une expérience de co-localisation entre les deux stations laser fixe du plateau de Calern, l'analyse est basée sur l'ajustement, par station, de coordonnées et d'un biais instrumental moyen à partir d'une orbite de référence des satellites LAGEOS. Des variations saisonnières ont été mises en évidence dans les séries temporelles des différentes composantes. La comparaison locale des déformations de la croûte terrestre se traduisant par des variations d'altitude issues des données laser a montré une cohérence remarquable avec les mesures du gravimètre absolu transportable FG5. Des signaux de même amplitude ont aussi été observés par GPS. Ces variations sont également mises en évidence à l'échelle mondiale et leur interprétation géophysique est faite (combinaison des effets de marées terrestres et polaire

  15. Chromatin modification in zebrafish development.

    PubMed

    Cayuso Mas, Jordi; Noël, Emily S; Ober, Elke A

    2011-01-01

    The generation of complex organisms requires that an initial population of cells with identical gene expression profiles can adopt different cell fates during development by progressively diverging transcriptional programs. These programs depend on the binding of transcritional regulators to specific genomic sites, which in turn is controlled by modifications of the chromatin. Chromatin modifications may occur directly upon DNA by methylation of specific nucleotides, or may involve post-translational modification of histones. Local regulation of histone post-translational modifications regionalizes the genome into euchromatic regions, which are more accessible to DNA-binding factors, and condensed heterochromatic regions, inhibiting the binding of such factors. In addition, these modifications may be required in a genome-wide fashion for processes such as DNA replication or chromosome condensation. From an embryologist's point of view chromatin modifications are intensively studied in the context of imprinting and have more recently received increasing attention in understanding the basis of pluripotency and cellular differentiation. Here, we describe recently uncovered roles of chromatin modifications in zebrafish development and regeneration, as well as available resources and commonly used techniques. We provide a general introduction into chromatin modifications and their respective functions with a focus on gene transcription, as well as key aspects of their roles in the early zebrafish embryo, neural development, formation of the digestive system and tissue regeneration.

  16. Surface modification in microchip electrophoresis.

    PubMed

    Belder, Detlev; Ludwig, Martin

    2003-11-01

    Different approaches and techniques for surface modification of microfluidic devices applied for microchip electrophoresis are reviewed. The main focus is on the improved electrophoretic separation by reducing analyte-wall interactions and manipulation of electroosmosis. Approaches and methods for permanent and dynamic surface modification of microfluidic devices, manufactured from glass, quartz and also different polymeric substrates, are described.

  17. Body Modification and Suicidal Behavior

    ERIC Educational Resources Information Center

    Hicinbothem, Julie; Gonsalves, Sonia; Lester, David

    2006-01-01

    In a large sample of individuals who belong to a website for body modification, having body modifications (e.g., piercings, tattoos, scarification and surgical procedures) was associated with a higher incidence of prior suicidality (i.e., suicidal ideation and attempted suicide). However, controls for self-reported depression weakened the strength…

  18. Surface Modification of Intraocular Lenses

    PubMed Central

    Huang, Qi; Cheng, George Pak-Man; Chiu, Kin; Wang, Gui-Qin

    2016-01-01

    Objective: This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs). Data Sources: All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect. Study Selection: The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded. Results: Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO2, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments. Conclusion: The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs. PMID:26830993

  19. RNA modification in Cajal bodies.

    PubMed

    Meier, U Thomas

    2016-10-24

    Aside from nucleoli, Cajal bodies (CBs) are the best-characterized organelles of mammalian cell nuclei. Like nucleoli, CBs concentrate ribonucleoproteins (RNPs), in particular, spliceosomal small nuclear RNPs (snRNPs) and small nucleolar RNPs (snoRNPs). In one of the best-defined functions of CBs, most of the snoRNPs are involved in site-specific modification of snRNAs. The two major modifications are pseudouridylation and 2'-O-methylation that are guided by the box H/ACA and C/D snoRNPs, respectively. This review details the modifications, their function, the mechanism of modification, and the machineries involved. We dissect the different classes of noncoding RNAs that meet in CBs, guides and substrates. Open questions and conundrums, often raised and appearing due to experimental limitations, are pointed out and discussed. The emphasis of the review is on mammalian CBs and their function in modification of noncoding RNAs.

  20. Chemical Protein Modification through Cysteine.

    PubMed

    Gunnoo, Smita B; Madder, Annemieke

    2016-04-01

    The modification of proteins with non-protein entities is important for a wealth of applications, and methods for chemically modifying proteins attract considerable attention. Generally, modification is desired at a single site to maintain homogeneity and to minimise loss of function. Though protein modification can be achieved by targeting some natural amino acid side chains, this often leads to ill-defined and randomly modified proteins. Amongst the natural amino acids, cysteine combines advantageous properties contributing to its suitability for site-selective modification, including a unique nucleophilicity, and a low natural abundance--both allowing chemo- and regioselectivity. Native cysteine residues can be targeted, or Cys can be introduced at a desired site in a protein by means of reliable genetic engineering techniques. This review on chemical protein modification through cysteine should appeal to those interested in modifying proteins for a range of applications.

  1. 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.

  2. Étude par chromatographie gazeuse inverse, à concentration finie, des propriétés de surface d'échantillons obtenus par traitement thermique de la goethite : distribution des sites d'adsorption des alcanes

    NASA Astrophysics Data System (ADS)

    Brendlé, E.; Balard, H.; Papirer, E.

    1998-07-01

    Inverse Gas Chromatography (IGC), at finite concentration conditions, was applied for the evaluation of the surface properties of hematite samples obtained by heat treatment of goethite. From the alkane adsorption isotherms, the distribution of surface sites according to the adsorption energy is determined. It is shown that the surface of hematite undergoes significant changes when heated up to 500 circC. La chromatographie Gazeuse Inverse (CGI), à concentration finie, a été utilisée pour évaluer les propriétés de surface d'échantillons d'hématite obtenus par traitement thermique de la goethite. A partir des isothermes d'adsorption des alcanes, on détermine la courbe de distribution des sites de surface en fonction de l'énergie d'adsorption de molécules sondes. On montre que ces courbes évoluent en fonction du traitement thermique de la goethite et traduisent une importante modification de surface de l'hématite formée après un chauffage à 500 circC.

  3. Surface modification of bioceramics

    NASA Astrophysics Data System (ADS)

    Monkawa, Akira

    Hydroxyapatite [Ca10(PO4)6(OH)2, HAp] is a major inorganic component of bone and teeth tissues and has the excellent biocompatibility and high osteoconductivity. The interactions between HAp and protein or cell have been studied. The HAp related bioceramics such as bone substitute, coating substance of metal implants, inorganic-polymer composites, and cell culture. We described two methods; (1) surface modification of HAp using organosilane; (2) fabrication of HAp ultra-thin layer on gold surface for protein adsorption analyzed with QCM-D technique. The interfacial interaction between collagen and HAp in a nano-region was controlled by depositing the organosilane of n-octadecyltrimethoxysilane (ODS: -CH3) or aminopropyltriethoxysilane (APTS: -NH2) with a chemical vapor deposition method. The morphologies of collagen adsorbed on the surfaces of HAp and HAp deposited with APTS were similar, however that of the surface with ODS was apparently different, due to the hydrophobic interaction between the organic head group of -CH3 and residual groups of collagen. We present a method for coating gold quartz crystal microbalance with dissipation (QCM-D) sensor with ultra-thin layer of hydroxyapatite nanocrystals evenly covering and tightly bound to the surface. The hydroxyapatite sensor operated in liquid with high stability and sensitivity. The in-situ adsorption mechanism and conformational change of fibrinogen on gold, titanium and hydroxyapatite surfaces were investigated by QCM-D technique and Fourier-transform infrared spectroscopy. The study indicates that the hydroxyapatite sensor is applicable for qualitative and conformational analysis of protein adsorption.

  4. 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

  5. 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.

  6. 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.

  7. Chatting histone modifications in mammals

    PubMed Central

    Izzo, Annalisa

    2010-01-01

    Eukaryotic chromatin can be highly dynamic and can continuously exchange between an open transcriptionally active conformation and a compacted silenced one. Post-translational modifications of histones have a pivotal role in regulating chromatin states, thus influencing all chromatin dependent processes. Methylation is currently one of the best characterized histone modification and occurs on arginine and lysine residues. Histone methylation can regulate other modifications (e.g. acetylation, phosphorylation and ubiquitination) in order to define a precise functional chromatin environment. In this review we focus on histone methylation and demethylation, as well as on the enzymes responsible for setting these marks. In particular we are describing novel concepts on the interdependence of histone modifications marks and discussing the molecular mechanisms governing this cross-talks. PMID:21266346

  8. Respiratory psychophysiology and behavior modification.

    PubMed

    Ley, R

    2001-09-01

    This article was written as an introduction to a special issue of Behavior Modification dedicated to studies in the field of respiratory psychophysiology. Although the invited articles that constitute this special issue cover a fairly broad range of topics, priority was given to articles that focus on the role of respiration in panic disorder. Attention is directed to the fundamental role of breathing in applied psychophysiology and to the encouragement of research in the modification of breathing behavior. The connection between respiratory psychophysiology and behavior modification is explained by reference to (a) a recent article on Pavlovian and operant control of breathing behavior and (b) four published volumes of selected articles dedicated exclusively to the field of respiratory psychophysiology. The present special issue of Behavior Modification marks the fifth volume.

  9. MODIFICATIONS OF THE RAND REAC,

    DTIC Science & Technology

    The major items of the modification program were the installation of a removable plugboard of the type used on the International Business Machines punched card tabulators, and a digital readout device.

  10. Developpement D'un Modele Climatique Regional: Fizr Simulation des Conditions de Janvier de la Cote Ouest Nord Americaine

    NASA Astrophysics Data System (ADS)

    Goyette, Stephane

    1995-11-01

    Le sujet de cette these concerne la modelisation numerique du climat regional. L'objectif principal de l'exercice est de developper un modele climatique regional ayant les capacites de simuler des phenomenes de meso-echelle spatiale. Notre domaine d'etude se situe sur la Cote Ouest nord americaine. Ce dernier a retenu notre attention a cause de la complexite du relief et de son controle sur le climat. Les raisons qui motivent cette etude sont multiples: d'une part, nous ne pouvons pas augmenter, en pratique, la faible resolution spatiale des modeles de la circulation generale de l'atmosphere (MCG) sans augmenter a outrance les couts d'integration et, d'autre part, la gestion de l'environnement exige de plus en plus de donnees climatiques regionales determinees avec une meilleure resolution spatiale. Jusqu'alors, les MCG constituaient les modeles les plus estimes pour leurs aptitudes a simuler le climat ainsi que les changements climatiques mondiaux. Toutefois, les phenomenes climatiques de fine echelle echappent encore aux MCG a cause de leur faible resolution spatiale. De plus, les repercussions socio-economiques des modifications possibles des climats sont etroitement liees a des phenomenes imperceptibles par les MCG actuels. Afin de circonvenir certains problemes inherents a la resolution, une approche pratique vise a prendre un domaine spatial limite d'un MCG et a y imbriquer un autre modele numerique possedant, lui, un maillage de haute resolution spatiale. Ce processus d'imbrication implique alors une nouvelle simulation numerique. Cette "retro-simulation" est guidee dans le domaine restreint a partir de pieces d'informations fournies par le MCG et forcee par des mecanismes pris en charge uniquement par le modele imbrique. Ainsi, afin de raffiner la precision spatiale des previsions climatiques de grande echelle, nous developpons ici un modele numerique appele FIZR, permettant d'obtenir de l'information climatique regionale valide a la fine echelle spatiale

  11. 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

  12. Data Analysis Strategies for Protein Modification Identification.

    PubMed

    Fu, Yan

    2016-01-01

    Mass spectrometry-based proteomics provides a powerful tool for large-scale analysis of protein modifications. Statistical and computational analysis of mass spectrometry data is a key step in protein modification identification. This chapter presents common and advanced data analysis strategies for modification identification, including variable modification search, unrestrictive approaches for modification discovery, false discovery rate estimation and control methods, and tools for modification site localization.

  13. Epigenetic modifications and diabetic retinopathy.

    PubMed

    Kowluru, Renu A; Santos, Julia M; Mishra, Manish

    2013-01-01

    Diabetic retinopathy remains one of the most debilitating chronic complications, but despite extensive research in the field, the exact mechanism(s) responsible for how retina is damaged in diabetes remains ambiguous. Many metabolic pathways have been implicated in its development, and genes associated with these pathways are altered. Diabetic environment also facilitates epigenetics modifications, which can alter the gene expression without permanent changes in DNA sequence. The role of epigenetics in diabetic retinopathy is now an emerging area, and recent work has shown that genes encoding mitochondrial superoxide dismutase (Sod2) and matrix metalloproteinase-9 (MMP-9) are epigenetically modified, activates of epigenetic modification enzymes, histone lysine demethylase 1 (LSD1), and DNA methyltransferase are increased, and the micro RNAs responsible for regulating nuclear transcriptional factor and VEGF are upregulated. With the growing evidence of epigenetic modifications in diabetic retinopathy, better understanding of these modifications has potential to identify novel targets to inhibit this devastating disease. Fortunately, the inhibitors and mimics targeted towards histone modification, DNA methylation, and miRNAs are now being tried for cancer and other chronic diseases, and better understanding of the role of epigenetics in diabetic retinopathy will open the door for their possible use in combating this blinding disease.

  14. Surface modification by molecular ions

    SciTech Connect

    Hanley, L.; Schultz, D. G.; Ada, E. T.

    1999-06-10

    There are several advantages in using molecular ions for surface modification. The modification can be confined to the uppermost layer of the surface, the molecular character of the ion can be imparted to the surface, and sputter yields are often higher. These effects are demonstrated by the use of mass selected ion beams incident on well characterized surfaces. Energy transfer is examined by detecting the masses and energies of ions scattered off surfaces and performing molecular dynamics simulations. Surface modification is followed by chemical analysis with x-ray photoelectron spectroscopy and surface mass spectrometry. TRIDYN monte carlo simulations are used to support some of the modification experiments. Energy transfer is examined for Si(CD{sub 3}){sub 3}{sup +} scattered off clean and hexanethiolate covered Au(111). Adsorbate desorption cross sections and substrate damage depths for NH{sub 3}/CO/Ni(111) are compared for 10-1000 eV isobaric atomic and polyatomic ions, Xe{sup +} and SF{sub 5}{sup +}. The surface chemical modification of polystyrene thin films by 10-100 eV SF{sub 5}{sup +} and C{sub 3}F{sub 5}{sup +} ions is also examined.

  15. Epigenetic Modifications in Essential Hypertension.

    PubMed

    Wise, Ingrid A; Charchar, Fadi J

    2016-03-25

    Essential hypertension (EH) is a complex, polygenic condition with no single causative agent. Despite advances in our understanding of the pathophysiology of EH, hypertension remains one of the world's leading public health problems. Furthermore, there is increasing evidence that epigenetic modifications are as important as genetic predisposition in the development of EH. Indeed, a complex and interactive genetic and environmental system exists to determine an individual's risk of EH. Epigenetics refers to all heritable changes to the regulation of gene expression as well as chromatin remodelling, without involvement of nucleotide sequence changes. Epigenetic modification is recognized as an essential process in biology, but is now being investigated for its role in the development of specific pathologic conditions, including EH. Epigenetic research will provide insights into the pathogenesis of blood pressure regulation that cannot be explained by classic Mendelian inheritance. This review concentrates on epigenetic modifications to DNA structure, including the influence of non-coding RNAs on hypertension development.

  16. Playing TETris with DNA modifications

    PubMed Central

    Delatte, Benjamin; Deplus, Rachel; Fuks, François

    2014-01-01

    Methylation of the fifth carbon of cytosine was the first epigenetic modification to be discovered in DNA. Recently, three new DNA modifications have come to light: hydroxymethylcytosine, formylcytosine, and carboxylcytosine, all generated by oxidation of methylcytosine by Ten Eleven Translocation (TET) enzymes. These modifications can initiate full DNA demethylation, but they are also likely to participate, like methylcytosine, in epigenetic signalling per se. A scenario is emerging in which coordinated regulation at multiple levels governs the participation of TETs in a wide range of physiological functions, sometimes via a mechanism unrelated to their enzymatic activity. Although still under construction, a sophisticated picture is rapidly forming where, according to the function to be performed, TETs ensure epigenetic marking to create specific landscapes, and whose improper build-up can lead to diseases such as cancer and neurodegenerative disorders. PMID:24825349

  17. Surface modification for corrosion resistance

    SciTech Connect

    Natesan, K.

    1993-06-01

    The raw gas environments that arise from coal gasification have chemical compositions that are low in pO{sub 2} and moderate-to-high in pS{sub 2}. Metallic materials for service in such an environment undergo predominantly sulfidation attack at temperatures of 400 to 700{degree}C. Modification of alloy compositions in bulk can alter the scaling processes and lead to improvements in corrosion resistance, but the benefits can only be attained at temperatures much higher than the service temperatures of the components. Modification of surfaces of structural components by several of the coating techniques examined in this study showed substantial benefit in corrosion resistance when tested in simulated coal gasification environments. The paper presents several examples of surface modification and their corrosion performance.

  18. [Posttranscriptional messenger RNA modifications in eukaryotes].

    PubMed

    Laptev, I G; Golovina, A Ya; Sergiev, P V; Dontsova, O A

    2015-01-01

    Genomewide mapping of posttranscriptional modification in eukaryotic RNA allowed to reveal tens of thousands modification sites. Among modified nucleotides of eukaryotic RNA 6-methyladenosine, 5-methylcytidine, pseudouridine, inosine, and others. Many modification sites are conserved, many are regulated. Function is known for a small subset of modified nucleotides, while the role of majority of them is still obscure. Global character of mRNA modifications allowed scientists to coin a new term, RNA epigenetics. The review is about posttranscriptional messenger RNA modifications in eukaryotes. Main modifications, their role in cell, their mapping techniques and proteins, that are responsible for such RNA modifications are observed.

  19. 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.

  20. Microbial profile modification with spores

    SciTech Connect

    Bae, J.H.; Chambers, K.T.; Lee, H.O.

    1996-08-01

    To overcome the shortcomings of conventional, near-wellbore profile modification methods, a microbial profile modification (MPM) method with spores was investigated. A halotolerant, spore-forming mesophile was isolated and characterized. These biopolymer-producing spores propagate easily in Berea cores with permeabilities more than about 500 md. With a specifically formulated nutrient package, they are readily germinated and produce biofilm, which reduces the permeability of the rock. The depth of penetration and the degree of permeability reduction can be controlled by varying injection schemes.

  1. Mapping chromatin modifications in nanochannels

    NASA Astrophysics Data System (ADS)

    Lim, Shuang Fang; Karpusenko, Alena; Riehn, Robert

    2013-03-01

    DNA and chromatin are elongated to a fixed fraction of their contour length when introduced into quasi-1d nanochannels. Because single molecules are analyzed, their hold great potential for the analysis for the genetic analysis of material from single cells. In this study, we have reconstituted chromatin with histones from a variety of sources, and mapped the modification profile of the chromatin. We monitored methylation and acetylation patterns of the histone tail protein residues using fluorescently labelled antibodies. Using those, we distinguished chromatin reconstituted from chicken erythrocytes, calf thymus, and HeLa cells. We discuss prospects for profiling histone modifications for whole chromosomes from single cells.

  2. 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.

  3. 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.

  4. Chemical modification of semiconductor surfaces

    NASA Technical Reports Server (NTRS)

    Finklea, H. O.

    1981-01-01

    Results of research on the chemical modification of TiO2 powders in the gas phase and the examination of the modified powders by infrared absorption spectroscopy are comprehensively summarized. The range of information obtainable by IR spectroscopy of chemically modified semiconductors, and a definition of the optimum reaction conditions for synthesizing a monolayer of methylsilanes using vapor phase reaction conditions were considered.

  5. Carbohydrate post-glycosylational modifications

    PubMed Central

    Yu, Hai; Chen, Xi

    2008-01-01

    Carbohydrate modification is a common phenomenon in nature. Many carbohydrate modifications such as some epimerization, O-acetylation, O-sulfation, O-methylation, N-deacetylation, and N-sulfation, take place after the formation of oligosaccharide or polysaccharide backbones. These modifications can be categorized as carbohydrate post-glycosylational modifications (PGMs). Carbohydrate PGMs further extend the complexity of the structures and the synthesis of carbohydrates and glycoconjugates. They also increase the capacity of the biological information that can be controlled by finely tuning the structures of carbohydrates. Developing efficient methods to obtain structurally defined naturally occurring oligosaccharides, polysaccharides, and glycoconjugates with carbohydrate PGMs is essential for understanding the biological significance of carbohydrate PGMs. Combine with high-throughput screening methods, synthetic carbohydrates with PGMs are invaluable probes in structure-activity relationship studies. We illustrate here several classes of carbohydrates with PGMs and their applications. Recent progress in chemical, enzymatic, and chemoenzymatic syntheses of these carbohydrates and their derivatives are also presented. PMID:17340000

  6. Plasma surface modification of polymers

    NASA Technical Reports Server (NTRS)

    Hirotsu, T.

    1980-01-01

    Thin plasma polymerization films are discussed from the viewpoint of simplicity in production stages. The application of selective, absorbent films and films used in selective permeability was tested. The types of surface modification of polymers discussed are: (1) plasma etching, (2) surface coating by plasma polymerized thin films, and (3) plasma activation surface graft polymerization.

  7. Weather Modification: The Ultimate Weapon

    DTIC Science & Technology

    1993-04-01

    All but nobody does anything about it -- Mark Twain liboducthm Weather modification. The very words conjure up an Image of quackery, chdatanism and...President, a few high-ranking military officers, and the assigned aircrew. We had come a long way since Mark Twain - something was being done about the

  8. Changing Attitudes Through Behavior Modification.

    ERIC Educational Resources Information Center

    Whipple, W. Scott

    This article describes the philosophy and methods used by the staff at the Granite Alternative School in changing student attitudes through behavior modification. The students involved all have a failure syndrome or low self-image, and are dropouts from traditional high schools. Among the techniques used are: (1) reinforcing good behavior (praise…

  9. Supervisory Workbook on Behavior Modification.

    ERIC Educational Resources Information Center

    Arkin, Ronald; And Others

    This workbook is designed to be used with the trainer's manual in supervisory training sessions on behavior modification of employees. This is one of four manuals prepared to aid supervisors in training disadvantaged groups using social reinforcement techniques. Related documents are available as VT 018 031-VT 018 035 in this issue. (MF)

  10. Demonstrating Allotropic Modifications of Sulfur.

    ERIC Educational Resources Information Center

    McCarty, Jillian L.; Dragojlovic, Veljko

    2002-01-01

    Shows how a common demonstration that consists of slowly heating sulfur powder in a test tube to illustrate sulfur's allotropic modifications can convince students of conclusions about the moon Io which they often find surprising. Describes the demonstration in full. (Author/MM)

  11. 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

  12. 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

  13. 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).

  14. 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.

  15. 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

  16. HHMD: the human histone modification database.

    PubMed

    Zhang, Yan; Lv, Jie; Liu, Hongbo; Zhu, Jiang; Su, Jianzhong; Wu, Qiong; Qi, Yunfeng; Wang, Fang; Li, Xia

    2010-01-01

    Histone modifications play important roles in chromatin remodeling, gene transcriptional regulation, stem cell maintenance and differentiation. Alterations in histone modifications may be linked to human diseases especially cancer. Histone modifications including methylation, acetylation and ubiquitylation probed by ChIP-seq, ChIP-chip and qChIP have become widely available. Mining and integration of histone modification data can be beneficial to novel biological discoveries. There has been no comprehensive data repository that is exclusive for human histone modifications. Therefore, we developed a relatively comprehensive database for human histone modifications. Human Histone Modification Database (HHMD, http://bioinfo.hrbmu.edu.cn/hhmd) focuses on the storage and integration of histone modification datasets that were obtained from laboratory experiments. The latest release of HHMD incorporates 43 location-specific histone modifications in human. To facilitate data extraction, flexible search options are built in HHMD. It can be searched by histone modification, gene ID, functional categories, chromosome location and cancer name. HHMD also includes a user-friendly visualization tool named HisModView, by which genome-wide histone modification map can be shown. HisModView facilitates the acquisition and visualization of histone modifications. The database also has manually curated information of histone modification dysregulation in nine human cancers.

  17. Posttranslational modification and quality control.

    PubMed

    Wang, Xuejun; Pattison, J Scott; Su, Huabo

    2013-01-18

    Protein quality control functions to minimize the level and toxicity of misfolded proteins in the cell. Protein quality control is performed by intricate collaboration among chaperones and target protein degradation. The latter is performed primarily by the ubiquitin-proteasome system and perhaps autophagy. Terminally misfolded proteins that are not timely removed tend to form aggregates. Their clearance requires macroautophagy. Macroautophagy serves in intracellular quality control also by selectively segregating defective organelles (eg, mitochondria) and targeting them for degradation by the lysosome. Inadequate protein quality control is observed in a large subset of failing human hearts with a variety of causes, and its pathogenic role has been experimentally demonstrated. Multiple posttranslational modifications can occur to substrate proteins and protein quality control machineries, promoting or hindering the removal of the misfolded proteins. This article highlights recent advances in posttranslational modification-mediated regulation of intracellular quality control mechanisms and its known involvement in cardiac pathology.

  18. Modification of chemotherapy by nitroimidazoles

    SciTech Connect

    Siemann, D.W.

    1984-09-01

    The potentiation of chemotherapeutic agents by radiation sensitizers has been extensively studied for several years. There is little doubt that the effectiveness of certain anti-cancer drugs, primarily alkylating agents, can readily be enhanced both in vitro and in vivo through the addition of a sensitizer. While enhanced effects have been observed in certain critical normal tissues, in general most animal model studies have demonstrated a therapeutic gain at large sensitizer doses. This approach to combination therapies therefore appears promising. Yet many questions concerning the interaction between chemotherapeutic agents and radiosensitizers, particularly in the aspects of modification of chemotherapy by nitroimidazoles are reviewed and discussed. These address the importance in chemopotentiation of (i) hypoxia, (ii) alterations in DNA damage and/or repair, (iii) depletion of intracellular sulfhydryls and (iv) modification of drug pharmacokinetics.

  19. Medium Modification of Vector Mesons

    SciTech Connect

    Chaden Djalali, Michael Paolone, Dennis Weygand, Michael H. Wood, Rakhsha Nasseripour

    2011-03-01

    The theory of the strong interaction, Quantum Chromodynamics (QCD), has been remarkably successful in describing high-energy and short-distance-scale experiments involving quarks and gluons. However, applying QCD to low energy and large-distance scale experiments has been a major challenge. Various QCD-inspired models predict a partial restoration of chiral symmetry in nuclear matter with modifications of the properties of hadrons from their free-space values. Measurable changes such as a shift in mass and/or a change of width are predicted at normal nuclear density. Photoproduction of vector mesons off nuclei have been performed at different laboratories. The properties of the ρ, ω and φ mesons are investigated either directly by measuring their mass spectra or indirectly through transparency ratios. The latest results regarding medium modifications of the vector mesons in the nuclear medium will be discussed.

  20. 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

  1. Cradle modification for hydraulic ram

    SciTech Connect

    Koons, B.M.

    1995-03-02

    The analysis of the cradle hydraulic system considers stress, weld strength, and hydraulic forces required to lift and support the cradle/pump assembly. The stress and weld strength of the cradle modifications is evaluated to ensure that they meet the requirements of the American Institute for Steel Construction (AISC 1989). The hydraulic forces are evaluated to ensure that the hydraulic system is capable of rotating the cradle and pump assembly to the vertical position (between 70{degrees} and 90{degrees}).

  2. Atmospheric Plasma for Surface Modification

    DTIC Science & Technology

    2011-02-01

    Plasma for Surface Modification 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...barrier coatings, dry low friction surfaces • Deposition Polymerized hydrocarbon coatings, chemical barriers, scratch resistant coatings, glass-like... surfaces , diamond like films • Oxidation/reduction Organic and inorganic functionalities • Activation. Hydroxyl, carboxylic, carbonyl, amine, vinyl

  3. 5 A, version modifée

    PubMed Central

    Vallis, Michael; Piccinini-Vallis, Helena; Sharma, Arya M.; Freedhoff, Yoni

    2013-01-01

    Objectif Adapter le modèle 5 A pour offrir aux professionnels des soins primaires un cadre de counseling sur l'obésité. Sources des données Une recension systématique des ouvrages spécialisés a été effectuée dans MEDLINE à l'aide des expressions de recherche 5 A's (49 articles recensés, tous pertinents) et 5 A's et primary care (8 articles recensés, tous redondants). On a aussi fait une recherche dans les sites web du National Institute of Health et de l'Organisation mondiale de la Santé. Message principal L'approche 5 A (autorisation, analyse, avis, accord et aide ou ask, assess, advise, agree et assist en anglais), élaborée pour la cessation du tabagisme, peut être adaptée au counseling sur l'obésité. Demander l'autorisation de discuter du poids; ne pas porter de jugement et explorer la volonté du patient de changer. Analyser l'indice de masse corporelle, la circonférence de la taille et le stade de l'obésité; explorer les déclencheurs et les complications de l'excès de poids. Donner son avis sur les risques de l'obésité pour la santé, les bienfaits d'une modeste perte de poids, la nécessité d'une stratégie à long terme et les options de traitements. Se mettre d'accord sur des attentes, des objectifs et des changements comportementaux réalistes pour perdre du poids et sur les détails précis du plan de traitement. Assister dans l'identifcation et l'atténuation des obstacles; offrir des ressources, aider à trouver et à consulter les services appropriés et organiser un suivi périodique. Conclusion Les 5 A représentent une stratégie d'intervention comportementale fondée sur des données probantes qui a le potentiel d'améliorer le taux de réussite de la gestion du poids en soins primaires.

  4. 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.

  5. [Advances in genetic modification technologies].

    PubMed

    Zhang, Baixue; Sun, Qixin; Li, Haifeng

    2015-08-01

    Genetic modification technology is a new molecular tool for targeted genome modification. It includes zinc finger nucleases (ZFN) technology, transcription activator-like effector nucleases (TALEN) technology and clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) (CRISPR-Cas) nucleases technology. All of these nucleases create DNA double-strand breaks (DSB) at chromosomal targeted sites and induce cell endogenous mechanisms that are primarily repaired by the non-homologous end joining (NHEJ) or homologous recombination (HR) pathway, resulting in targeted endogenous gene knock-out or exogenous gene insertion. In recent years, genetic modification technologies have been successfully applied to bacteria, yeast, human cells, fruit fly, zebra fish, mouse, rat, livestock, cynomolgus monkey, Arabidopsis, rice, tobacco, maize, sorghum, wheat, barley and other organisms, showing its enormous advantage in gene editing field. Especially, the newly developed CRISPR-Cas9 system arose more attention because of its low cost, high effectiveness, simplicity and easiness. We reviewed the principles and the latest research progress of these three technologies, as well as prospect of future research and applications.

  6. Protein modification by adenine propenal.

    PubMed

    Shuck, Sarah C; Wauchope, Orrette R; Rose, Kristie L; Kingsley, Philip J; Rouzer, Carol A; Shell, Steven M; Sugitani, Norie; Chazin, Walter J; Zagol-Ikapitte, Irene; Boutaud, Olivier; Oates, John A; Galligan, James J; Beavers, William N; Marnett, Lawrence J

    2014-10-20

    Base propenals are products of the reaction of DNA with oxidants such as peroxynitrite and bleomycin. The most reactive base propenal, adenine propenal, is mutagenic in Escherichia coli and reacts with DNA to form covalent adducts; however, the reaction of adenine propenal with protein has not yet been investigated. A survey of the reaction of adenine propenal with amino acids revealed that lysine and cysteine form adducts, whereas histidine and arginine do not. N(ε)-Oxopropenyllysine, a lysine-lysine cross-link, and S-oxopropenyl cysteine are the major products. Comprehensive profiling of the reaction of adenine propenal with human serum albumin and the DNA repair protein, XPA, revealed that the only stable adduct is N(ε)-oxopropenyllysine. The most reactive sites for modification in human albumin are K190 and K351. Three sites of modification of XPA are in the DNA-binding domain, and two sites are subject to regulatory acetylation. Modification by adenine propenal dramatically reduces XPA's ability to bind to a DNA substrate.

  7. Epigenetic modifications in rheumatoid arthritis.

    PubMed

    Strietholt, Simon; Maurer, Britta; Peters, Marvin A; Pap, Thomas; Gay, Steffen

    2008-01-01

    Over the last decades, genetic factors for rheumatoid diseases like the HLA haplotypes have been studied extensively. However, during the past years of research, it has become more and more evident that the influence of epigenetic processes on the development of rheumatic diseases is probably as strong as the genetic background of a patient. Epigenetic processes are heritable changes in gene expression without alteration of the nucleotide sequence. Such modifications include chromatin methylation and post-translational modification of histones or other chromatin-associated proteins. The latter comprise the addition of methyl, acetyl, and phosphoryl groups or even larger moieties such as binding of ubiquitin or small ubiquitin-like modifier. The combinatory nature of these processes forms a complex network of epigenetic modifications that regulate gene expression through activation or silencing of genes. This review provides insight into the role of epigenetic alterations in the pathogenesis of rheumatoid arthritis and points out how a better understanding of such mechanisms may lead to novel therapeutic strategies.

  8. DNA modifications: Another stable base in DNA

    NASA Astrophysics Data System (ADS)

    Brazauskas, Pijus; Kriaucionis, Skirmantas

    2014-12-01

    Oxidation of 5-methylcytosine has been proposed to mediate active and passive DNA demethylation. Tracking the history of DNA modifications has now provided the first solid evidence that 5-hydroxymethylcytosine is a stable epigenetic modification.

  9. 75 FR 41530 - Petitions for Modification; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... Safety and Health Administration Petitions for Modification; Correction AGENCY: Mine Safety and Health Administration, Labor. ACTION: Notice; correction. SUMMARY: The Mine Safety and Health Administration (MSHA... existing safety standards. The document contains an ] under II. Petitions for Modification,...

  10. Education relative a l'environnement (ERE): Une etude des representations sociales et des pratiques educatives d'enseignants de science et technologie du secondaire en contexte de formation continue

    NASA Astrophysics Data System (ADS)

    Collard-Fortin, Ugo

    Le developpement des sciences/technologie a tres clairement contribue a ce que ce dernier domaine de savoirs jouisse d'une place de choix au sein de notre societe. Au-dela des progres de notre civilisation inherents a ce dernier developpement, cette croissance amena avec elle un lot d'ineluctables dommages collateraux, contribuant en corollaire a l'emergence de diverses problematiques environnementales inquietantes pour lesquelles les valeurs ainsi que le mode de fonctionnement de la societe occidentale contemporaine sont largement tributaires. C'est entre autres en reponse a cet etat de fait que la recente vague de reforme de l'Education conduisit a l'integration, dans les curricula de sciences/technologie, de contenus relavant d'education relative a l'environnement (ERE). Face au changement, les enseignants de sciences ont du s'approprier ce nouveau programme afm de l'enseigner a leurs eleves. Toutefois, l'analyse de la situation montre que les prescriptions du programme en matiere d'ERE ne se sont pas toujours traduites en de reelles actions dans la pratique. Le contexte de notre etude s'est interesse aux pratiques educatives de l'ERE ainsi qu'a la representation sociale qui en decoule. Notre recherche aborde plus specifiquement la problematique de la modification de ces derniers objets chez les enseignants de sciences et technologie du deuxieme cycle du secondaire. Pour y arriver, nous avons propose a un groupe de trois praticiens de participer a une activite, en communaute de pratique, de formation continue orientee autour de thematiques ERE. Cette recherche developpement, s'inscrivant dans un paradigme qualitatif/interpretatif, s'est appuyee sur une cueillette de donnees effectuee a partir d'entrevues semi-dirigees, d'observations en situation et d'un groupe de discussion, au debut et a la fm de la formation continue. Les donnees brutes ont ete soumises a une demarche d'analyse inductive et ont genere diverses categories etayant nos objets de recherche

  11. 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.

  12. 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

  13. Energy conservation potential of surface modification technologies

    SciTech Connect

    Le, H.K.; Horne, D.M.; Silberglitt, R.S.

    1985-09-01

    This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

  14. 40 CFR 58.14 - System modification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... State, or where appropriate local, agency from making modifications to the SLAMS network for reasons... PAMS networks in bumped-up ozone nonattainment areas. These modifications must address changes invoked...) AMBIENT AIR QUALITY SURVEILLANCE Monitoring Network § 58.14 System modification. (a) The State, or...

  15. 40 CFR 58.14 - System modification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... State, or where appropriate local, agency from making modifications to the SLAMS network for reasons... PAMS networks in bumped-up ozone nonattainment areas. These modifications must address changes invoked...) AMBIENT AIR QUALITY SURVEILLANCE Monitoring Network § 58.14 System modification. (a) The State, or...

  16. 40 CFR 58.14 - System modification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... State, or where appropriate local, agency from making modifications to the SLAMS network for reasons... PAMS networks in bumped-up ozone nonattainment areas. These modifications must address changes invoked...) AMBIENT AIR QUALITY SURVEILLANCE Monitoring Network § 58.14 System modification. (a) The State, or...

  17. Modification Of Gear Teeth To Reduce Vibrations

    NASA Technical Reports Server (NTRS)

    Townsend, Dennis P.; Oswald, Fred B.; Lin, Hsiang Hsi

    1990-01-01

    Computer simulations yield data useful in designing for low noise. Effects of modifications in shape of gear teeth upon static transmission error and dynamic loading of gears now analyzed systematically. Design curves generated by conducting numerical simulations of dynamic effects at successive incremental modifications of gear systems operated at various applied loads. Modifications that result in minimum dynamic effect determined from design curves.

  18. 49 CFR 22.59 - Loan modifications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Loan modifications. 22.59 Section 22.59 Transportation Office of the Secretary of Transportation SHORT-TERM LENDING PROGRAM (STLP) Loan Administration § 22.59 Loan modifications. Any modification to the terms of the DOT OSDBU guarantee agreement...

  19. 49 CFR 22.59 - Loan modifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Loan modifications. 22.59 Section 22.59 Transportation Office of the Secretary of Transportation SHORT-TERM LENDING PROGRAM (STLP) Loan Administration § 22.59 Loan modifications. Any modification to the terms of the DOT OSDBU guarantee agreement...

  20. 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

  1. 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

  2. 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

  3. 30 CFR 18.81 - Field modification of approved (permissible) equipment; application for approval of modification...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Field modification of approved (permissible) equipment; application for approval of modification; approval of plans for modification before modification. 18.81 Section 18.81 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF...

  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. Mechanochemical modification of natural rubber

    NASA Astrophysics Data System (ADS)

    Mikhaylov, I. A.; Sukhareva, K. V.; Andriasyan, Yu. O.; Popov, A. A.; Vorontsov, N. V.

    2016-11-01

    Thermomechanochemical changes of SVR 3L natural rubber after the treatment in the internal rubber mixer in the self-heating mode were studied. The effect of the molecular mass and content of the gel fraction of natural rubber is shown. Properties of rubber compounds and vulcanized rubber are presented. Taking into account modern requirements, a new alternative technology of obtaining halogenated elastomers based on the solid-phase (mechanochemical) halide modification is created. New halogen-containing natural rubber produced by this technology proves themselves in the conditions of rubber production. New fluorinated natural rubber produced by this technology proves themselves in the conditions of rubber production.

  6. Modifications to Ivor Lewis esophagectomy.

    PubMed

    David, Elizabeth A; Marshall, M Blair

    2010-11-01

    The surgical approach to esophagectomy is variable. A number of factors are considered when determining the optimal approach to esophagectomy: location and extent of disease, fibrosis, additional patient factors and surgeon preference. One of the disadvantages to some approaches is the need for a change in position, which increases operative time. Also, because typically the abdomen is initially explored, patients may later be deemed unresectable at thoracotomy. We describe time saving modifications to the standard Ivor Lewis esophagectomy that eliminate the need for repositioning and facilitate a stapled end-to-end anastomosis.

  7. Homosexuality : treatment by behaviour modification.

    PubMed

    Pradhan, P V; Ayyar, K S; Bagadia, V N

    1982-01-01

    We present here the treatment of thirteen homosexuals by behaviour modification techniques. With classical electrical aversion and positive conditioning 8(61%) out of thirteen patients showed a change in orientation lasting on a six-month 1 year follow up. A marriageable age and indirect social pressures were positively correlated with improvement whereas the presence of a steady homosexual partner and habitual passive anal intercourse indicated a poor response. The techniques, the assessments, the onset and course of improvement and complications arc discussed. Our results and techniques are compared with those of other workers.

  8. 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

  9. Ion Beam Modification of Materials

    SciTech Connect

    Averback, B; de la Rubia, T D; Felter, T E; Hamza, A V; Rehn, L E

    2005-10-10

    This volume contains the proceedings of the 14th International Conference on Ion Beam Modification of Materials, IBMM 2004, and is published by Elsevier-Science Publishers as a special issue of Nuclear Instruments and Methods B. The conference series is the major international forum to present and discuss recent research results and future directions in the field of ion beam modification, synthesis and characterization of materials. The first conference in the series was held in Budapest, Hungary, 1978, and subsequent conferences were held every two years at locations around the Globe, most recently in Japan, Brazil, and the Netherlands. The series brings together physicists, materials scientists, and ion beam specialists from all over the world. The official conference language is English. IBMM 2004 was held on September 5-10, 2004. The focus was on materials science involving both basic ion-solid interaction processes and property changes occurring either during or subsequent to ion bombardment and ion beam processing in relation to materials and device applications. Areas of research included Nanostructures, Multiscale Modeling, Patterning of Surfaces, Focused Ion Beams, Defects in Semiconductors, Insulators and Metals, Cluster Beams, Radiation Effects in Materials, Photonic Devices, Ion Implantation, Ion Beams in Biology and Medicine including New Materials, Imaging, and Treatment.

  10. 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.

  11. 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

  12. 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.

  13. Germline modification of domestic animals

    PubMed Central

    Tang, L.; González, R.; Dobrinski, I.

    2016-01-01

    Genetically-modified domestic animal models are of increasing significance in biomedical research and agriculture. As authentic ES cells derived from domestic animals are not yet available, the prevailing approaches for engineering genetic modifications in those animals are pronuclear microinjection and somatic cell nuclear transfer (SCNT, also known as cloning). Both pronuclear microinjection and SCNT are inefficient, costly, and time-consuming. In animals produced by pronuclear microinjection, the exogenous transgene is usually inserted randomly into the genome, which results in highly variable expression patterns and levels in different founders. Therefore, significant efforts are required to generate and screen multiple founders to obtain animals with optimal transgene expression. For SCNT, specific genetic modifications (both gain-of-function and loss-of-function) can be engineered and carefully selected in the somatic cell nucleus before nuclear transfer. SCNT has been used to generate a variety of genetically modified animals such as goats, pigs, sheep and cattle; however, animals resulting from SCNT frequently suffer from developmental abnormalities associated with incomplete nuclear reprogramming. Other strategies to generate genetically-modified animals rely on the use of the spermatozoon as a natural vector to introduce genetic material into the female gamete. This sperm mediated DNA transfer (SMGT) combined with intracytoplasmatic sperm injection (ICSI) has relatively high efficiency and allows the insertion of large DNA fragments, which, in turn, enhance proper gene expression. An approach currently being developed to complement SCNT for producing genetically modified animals is germ cell transplantation using genetically modified male germline stem cells (GSCs). This approach relies on the ability of GSCs that are genetically modified in vitro to colonize the recipient testis and produce donor derived sperm upon transplantation. As the genetic change

  14. Germline modification of domestic animals.

    PubMed

    Tang, L; González, R; Dobrinski, I

    2015-01-01

    Genetically-modified domestic animal models are of increasing significance in biomedical research and agriculture. As authentic ES cells derived from domestic animals are not yet available, the prevailing approaches for engineering genetic modifications in those animals are pronuclear microinjection and somatic cell nuclear transfer (SCNT, also known as cloning). Both pronuclear microinjection and SCNT are inefficient, costly, and time-consuming. In animals produced by pronuclear microinjection, the exogenous transgene is usually inserted randomly into the genome, which results in highly variable expression patterns and levels in different founders. Therefore, significant efforts are required to generate and screen multiple founders to obtain animals with optimal transgene expression. For SCNT, specific genetic modifications (both gain-of-function and loss-of-function) can be engineered and carefully selected in the somatic cell nucleus before nuclear transfer. SCNT has been used to generate a variety of genetically modified animals such as goats, pigs, sheep and cattle; however, animals resulting from SCNT frequently suffer from developmental abnormalities associated with incomplete nuclear reprogramming. Other strategies to generate genetically-modified animals rely on the use of the spermatozoon as a natural vector to introduce genetic material into the female gamete. This sperm mediated DNA transfer (SMGT) combined with intracytoplasmatic sperm injection (ICSI) has relatively high efficiency and allows the insertion of large DNA fragments, which, in turn, enhance proper gene expression. An approach currently being developed to complement SCNT for producing genetically modified animals is germ cell transplantation using genetically modified male germline stem cells (GSCs). This approach relies on the ability of GSCs that are genetically modified in vitro to colonize the recipient testis and produce donor derived sperm upon transplantation. As the genetic change

  15. 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

  16. 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.

  17. 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).

  18. Protection des ions organiques contre les dommages induits a l'ADN par les electrons de basse energie

    NASA Astrophysics Data System (ADS)

    Dumont, Ariane

    'ADN de differentes epaisseurs, possedant entre 0 et 32 ions organiques/ nucleotide, ont ete irradies avec des electrons de 10eV. Les dommages induits par les electrons, sous forme de cassures, ont ete detectes par electrophorese. Nous avons demontre que le rendement de cassure simple brin diminuait de facon dramatique en fonction du nombre d'ions organiques/ nucleotide. Aussi peu que 2 ions organiques/ nucleotide sont suffisant pour decroitre le rendement de SSB de 70%. Cet effet radioprotecteur est en partie explique par l'augmentation de l'epaisseur des films, mais surtout par la modification du champ electrique a proximite de l'ADN, due a l'ajout de molecules chargees positivement. La modification du champ electrique pres de l'ADN altere les parametres de resonance comme le temps de vie de l'anion transitoire et la limite de dissociation, qui influent directement sur la section efficace d'attachement dissociatif. L'effet protecteur peut egalement etre explique par la restauration des bases anioniques deshydrogenees induites par l'attachement dissociatif de l'electron sur une base (G(-H)-). Ce sont les molecules Tris qui, en transferant un atome d'hydrogene ou un proton, restaurent les bases deshydrogenees et inhibent par le fait meme la formation de cassures simple brin. Ces resultats indiquent que les histones peuvent egalement participer a la reparation de dommages precoces induits a l'ADN avant qu'elles ne menent a des dommages encore plus nocifs et difficiles a reparer, comme les cassures simples brins. Mots cles : Electrons de basse energie, dommage a l'ADN, ions organiques, attachement dissociatif de l'electron.

  19. Utilisation de traceurs radioactifs pour l'évaluation du recrutement des leucocytes et des échanges vasculaires au niveau d'organes in~vivo. Description d'une méthode et discussion des problèmes d'interprétation sur quelques exemples

    NASA Astrophysics Data System (ADS)

    Bureau, M. F.

    1997-03-01

    An experimental method using simultaneously different γ emiter tracers was developed to evaluate inflammation in vivo. Experiments were performed on the anaesthetized guinea-pig to test pulmonary effects of inflammatory agents. Red blood cells, albumin and inflammatory cells (platelets or leucocytes) radiolabelled with 99m technetium, 131 iodine and 111 indium respectively were injected i.v. Their radioactivities were measured on a pulmonary region by external detection and on blood samples in a well type counter. From these measurements variations of the lung contents in red blood cells, extravascular albumin and non circulating leucocytes during inflammatory stimulation were evaluated. These parameters axe indexes of blood perfusion, vascular exchanges and leucocyte sequestration respectively. Fiability of the method and meaning of the parameters evaluated are discussed. Une méthode expérimentale utilisant simultanément différents traceurs γ a été développée pour évaluer l'inflammation in vivo. Des expériences ont été réalisées chez le cobaye anesthésié pour tester l'effet pulmonaire d'agents inflammatoires. Des globules rouges, de l'albumine et des cellules inflammatoires (plaquettes ou leucocytes) radiomarqués respectivement au technetium 99m, à l'iode 131 et à l'indium 111 sont injectés i.v. Leurs radioactivités sont mesurées sur une région pulmonaire par détection externe et sur des échantillons sanguins au compteur puit. À partir de ces mesures sont évaluées les variations des contenus pulmonaires en globules rouges, en albumine extravasculaire et en leucocytes non circulants lors d'une stimulation inflammatoire. Ces paramètres sont corrélés aux modifications de la perfusion, des échanges vasculaires et de la séquestration leucocytaire. La fiabilité de la méthode et la signification des paramètres évalués sont discutées.

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. Paper surface modification by lasers

    NASA Astrophysics Data System (ADS)

    Zekou, E.; Kotsifaki, D. G.; Serafetinides, A. A.

    2010-10-01

    Lasers can provide a precious tool to conservation process due to their accuracy and the controlled energy they deliver, especially to fragile organic material such as paper. The current study concerns laser modification such as paper cleaning, initially of test papers artificially soiled and then of an original book of the early 20th Century. The test objects were A4 copier paper, newspaper, and paper Whatman No.1056. During the experiments, ink of a pen, pencil and ink from a stamp was mechanically employed on each paper surface. Laser cleaning was applied using a Q-switched Nd:YAG operating at 532 nm and CO2 laser at 10.6 μm for various fluences. The experimental results were presented by using optical microscopy. Eventually, laser cleaning of ink was performed to a book of 1934, by choosing the best conditions and parameters from cleaning the test samples, like Nd:YAG laser operating at 532 nm.

  7. Surface Modification for Microreactor Fabrication

    PubMed Central

    Pijanowska, Dorota G.; Remiszewska, Elżbieta; Pederzolli, Cecilia; Lunelli, Lorenzo; Vendano, Michele; Canteri, Roberto; Dudziński, Konrad; Kruk, Jerzy; Torbicz, Wladyslaw

    2006-01-01

    In this paper, methods of surface modification of different supports, i.e. glass and polymeric beads for enzyme immobilisation are described. The developed method of enzyme immobilisation is based on Schiff's base formation between the amino groups on the enzyme surface and the aldehyde groups on the chemically modified surface of the supports. The surface of silicon modified by APTS and GOPS with immobilised enzyme was characterised by atomic force microscopy (AFM), time-of-flight secondary ion mass spectroscopy (ToF-SIMS) and infrared spectroscopy (FTIR). The supports with immobilised enzyme (urease) were also tested in combination with microreactors fabricated in silicon and Perspex, operating in a flow-through system. For microreactors filled with urease immobilised on glass beads (Sigma) and on polymeric beads (PAN), a very high and stable signal (pH change) was obtained. The developed method of urease immobilisation can be stated to be very effective.

  8. Genome recoding by tRNA modifications

    PubMed Central

    Tuorto, Francesca

    2016-01-01

    RNA modifications are emerging as an additional regulatory layer on top of the primary RNA sequence. These modifications are particularly enriched in tRNAs where they can regulate not only global protein translation, but also protein translation at the codon level. Modifications located in or in the vicinity of tRNA anticodons are highly conserved in eukaryotes and have been identified as potential regulators of mRNA decoding. Recent studies have provided novel insights into how these modifications orchestrate the speed and fidelity of translation to ensure proper protein homeostasis. This review highlights the prominent modifications in the tRNA anticodon loop: queuosine, inosine, 5-methoxycarbonylmethyl-2-thiouridine, wybutosine, threonyl–carbamoyl–adenosine and 5-methylcytosine. We discuss the functional relevance of these modifications in protein translation and their emerging role in eukaryotic genome recoding during cellular adaptation and disease. PMID:27974624

  9. Messenger RNA modifications: Form, distribution, and function.

    PubMed

    Gilbert, Wendy V; Bell, Tristan A; Schaening, Cassandra

    2016-06-17

    RNA contains more than 100 distinct modifications that promote the functions of stable noncoding RNAs in translation and splicing. Recent technical advances have revealed widespread and sparse modification of messenger RNAs with N(6)-methyladenosine (m(6)A), 5-methylcytosine (m(5)C), and pseudouridine (Ψ). Here we discuss the rapidly evolving understanding of the location, regulation, and function of these dynamic mRNA marks, collectively termed the epitranscriptome. We highlight differences among modifications and between species that could instruct ongoing efforts to understand how specific mRNA target sites are selected and how their modification is regulated. Diverse molecular consequences of individual m(6)A modifications are beginning to be revealed, but the effects of m(5)C and Ψ remain largely unknown. Future work linking molecular effects to organismal phenotypes will broaden our understanding of mRNA modifications as cell and developmental regulators.

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. 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...

  15. 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.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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

  2. 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.

  3. 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.

  4. The Modification of Compounds by Attributive Adjectives

    ERIC Educational Resources Information Center

    Berg, Thomas

    2011-01-01

    This paper examines the modification of nominal compounds by attributive adjectives in English. It draws on a distinction between compound-external (i.e. syntactic) and compound-internal (i.e. morphological) modification. An analysis is presented of more than 1000 pertinent cases, which are roughly equally divided into two-, three- and four-noun…

  5. Modifications Of Hydrostatic-Bearing Computer Program

    NASA Technical Reports Server (NTRS)

    Hibbs, Robert I., Jr.; Beatty, Robert F.

    1991-01-01

    Several modifications made to enhance utility of HBEAR, computer program for analysis and design of hydrostatic bearings. Modifications make program applicable to more realistic cases and reduce time and effort necessary to arrive at a suitable design. Uses search technique to iterate on size of orifice to obtain required pressure ratio.

  6. 46 CFR 309.7 - Modifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Modifications. 309.7 Section 309.7 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS VALUES FOR WAR RISK INSURANCE § 309.7 Modifications. The Maritime Administration reserves the right to exempt any vessel from the scope of this...

  7. 7 CFR 1467.13 - Modifications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.13 Modifications. (a... the program so long as the modification will not adversely affect the wetland functions and values for... of other lands that provide greater wetland functions and values at no additional cost to...

  8. Modification of integrated partial payload lifting assembly

    NASA Technical Reports Server (NTRS)

    Groah, Melodie; Haddock, Michael; Woodworth, Warren

    1986-01-01

    The Integrated Partial Payload Lifting Assembly (IPPLA) is currently used to transport and load experimental payloads into the cargo bay of the Space Shuttle. It is unable to carry the astronaut/passenger tunnel without a structural modification. The purpose of this design is to create a removalbe modification that will allow the IPPLA to lift and carry the passenger tunnel. Modifications evaluated were full-length insert beams which would extend through the existing strongback arms. These beam proposals were eliminated because of high cost and weight. Other proposals evaluated were attachments of cantilever beams to the existing strongback areas. The cantilever proposals reduced cost and weight compared to the full-length modifications. A third method evaluated was to simply make modifications to one side of the IPPLA therefore reducing the materials of the cantilever proposals by 40 percent. The design of the modification selected was completed with two channel beams jointly welded to a centered steel plate. The extension arm modification is inserted into the existing strongback channel beams and bolted into place. Two extension arms are added to one side of the IPPLA to provide the extra length needed to accommodate the passenger tunnel. The center counterbalance will then be offset about 20 inches to center gravity and therefore maintain horizontal status. The extension arm modification was selected because of minimum cost, low weight, and minimal installation time.

  9. 7 CFR 763.19 - Contract modification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Contract modification. 763.19 Section 763.19... AGRICULTURE SPECIAL PROGRAMS LAND CONTRACT GUARANTEE PROGRAM § 763.19 Contract modification. (a) The seller and buyer may modify the land contract to lower the interest rate and corresponding amortized...

  10. 7 CFR 634.26 - Contract modifications.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Contract modifications. 634.26 Section 634.26..., DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL CLEAN WATER PROGRAM Participant RCWP Contracts § 634.26 Contract modifications. (a) The administering agency may modify contracts previously entered into if it...

  11. 7 CFR 1410.33 - Contract modifications.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Contract modifications. 1410.33 Section 1410.33... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS CONSERVATION RESERVE PROGRAM § 1410.33 Contract modifications. (a) As agreed between CCC and the participant, a CRP contract may be modified in order to:...

  12. 7 CFR 636.10 - Modifications.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Modifications. 636.10 Section 636.10 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.10 Modifications. (a)...

  13. 7 CFR 636.10 - Modifications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Modifications. 636.10 Section 636.10 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.10 Modifications. (a)...

  14. 7 CFR 636.10 - Modifications.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Modifications. 636.10 Section 636.10 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVES PROGRAM § 636.10 Modifications. (a)...

  15. 7 CFR 636.10 - Modifications.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Modifications. 636.10 Section 636.10 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.10 Modifications. (a)...

  16. 7 CFR 636.10 - Modifications.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Modifications. 636.10 Section 636.10 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING WILDLIFE HABITAT INCENTIVE PROGRAM § 636.10 Modifications. (a)...

  17. Harnessing epigenome modifications for better crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemical DNA modifications such as methylation influence translation of the DNA code to specific genetic outcomes. While such modifications can be heritable, others are transient, and their overall contribution to plant genetic diversity remains intriguing but uncertain. The focus of this article is...

  18. 30 CFR 282.25 - Plan modification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Plan modification. 282.25 Section 282.25... § 282.25 Plan modification. Approved Delineation, Testing, and Mining Plans may be modified upon the... to modify an approved plan to adjust to changed conditions. If the lessee requests the change,...

  19. 38 CFR 36.4315 - Loan modifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2013-07-01 2013-07-01 false Loan modifications. 36...) LOAN GUARANTY Guaranty or Insurance of Loans to Veterans With Electronic Reporting § 36.4315 Loan modifications. (a) The terms of any guaranteed loan may be modified by written agreement between the holder...

  20. 38 CFR 36.4315 - Loan modifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Loan modifications. 36...) LOAN GUARANTY Guaranty or Insurance of Loans to Veterans With Electronic Reporting § 36.4315 Loan modifications. (a) The terms of any guaranteed loan may be modified by written agreement between the holder...

  1. 75 FR 41529 - Petitions for Modification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... Safety and Health Administration Petitions for Modification AGENCY: Mine Safety and Health Administration (MSHA), Labor. ACTION: Notice of petitions for modification of existing mandatory safety standards. SUMMARY: Section 101(c) of the Federal Mine Safety and Health Act of 1977 and 30 CFR part 44 govern...

  2. 45 CFR 160.104 - Modifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Modifications. 160.104 Section 160.104 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES ADMINISTRATIVE DATA STANDARDS AND RELATED REQUIREMENTS GENERAL ADMINISTRATIVE REQUIREMENTS General Provisions § 160.104 Modifications. (a) Except as provided...

  3. Behavior Modification: A Practical Guide for Teachers.

    ERIC Educational Resources Information Center

    Poteet, James A.

    This teachers guide in behavior modification is divided into five chapters. Chapter one, "Describing Behavior," presents methods for specifying behaviors in precise wording, labeling behavior, and deciding on the target behavior (behavior designated for modification). Chapter two, "Measuring Behavior," describes and illustrates by means of graphs…

  4. Mass modification experiment definition study

    SciTech Connect

    Forward, R.L.

    1996-12-31

    This report summarizes an attempt to find an experiment that would test the Haisch, Rueda, and Puthoff (HRP) conjecture that the mass and inertia of a body are induced effects brought about by changes in the quantum-fluctuation energy of the vacuum. It was not possible, however, to identify a definitive experiment. But, it was possible to identify an experiment that might be able to prove or disprove that the inertial mass of a body can be altered by making changes in the vacuum surrounding the body. Other experiments, which do not involve mass modification, but which teach something about the vacuum, were also defined and included in a ranked list of experiments. This report also contains an annotated bibliography. An interesting point raised by this paper is this: We can estimate the `vacuum energy density` to be 10{sup 108} J/cc, and the vacuum mass density to be 10{sup 94} g/cc, much higher numbers than those associated with nuclear energy. Although the field of `electromagnetic fluctuation energy of the vacuum` is admittedly an esoteric, little-understood field, it does seem to have definite potential as an energy source. 47 refs.

  5. 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

  6. 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

  7. Covariance Modifications to Subspace Bases

    SciTech Connect

    Harris, D B

    2008-11-19

    Adaptive signal processing algorithms that rely upon representations of signal and noise subspaces often require updates to those representations when new data become available. Subspace representations frequently are estimated from available data with singular value (SVD) decompositions. Subspace updates require modifications to these decompositions. Updates can be performed inexpensively provided they are low-rank. A substantial literature on SVD updates exists, frequently focusing on rank-1 updates (see e.g. [Karasalo, 1986; Comon and Golub, 1990, Badeau, 2004]). In these methods, data matrices are modified by addition or deletion of a row or column, or data covariance matrices are modified by addition of the outer product of a new vector. A recent paper by Brand [2006] provides a general and efficient method for arbitrary rank updates to an SVD. The purpose of this note is to describe a closely-related method for applications where right singular vectors are not required. This note also describes the SVD updates to a particular scenario of interest in seismic array signal processing. The particular application involve updating the wideband subspace representation used in seismic subspace detectors [Harris, 2006]. These subspace detectors generalize waveform correlation algorithms to detect signals that lie in a subspace of waveforms of dimension d {ge} 1. They potentially are of interest because they extend the range of waveform variation over which these sensitive detectors apply. Subspace detectors operate by projecting waveform data from a detection window into a subspace specified by a collection of orthonormal waveform basis vectors (referred to as the template). Subspace templates are constructed from a suite of normalized, aligned master event waveforms that may be acquired by a single sensor, a three-component sensor, an array of such sensors or a sensor network. The template design process entails constructing a data matrix whose columns contain the

  8. Perception des médecins résidents de la prise en charge et de la valorisation de la médecine familiale

    PubMed Central

    B-Lajoie, Marie-Renée; Carrier, Johanne

    2012-01-01

    Résumé Objectif Cette recherche visait à documenter la perception de la prise en charge chez les médecins résidents en médecine familiale. Type d’étude Un questionnaire électronique quantitatif bilingue de 10 questions. Contexte Québec. Participants Tous les résidents en médecine familiale au Québec, soit 747 résidents. Principaux paramètres de l’étude Le questionnaire visait à préciser les intentions des médecins résidents quant à leur perception de la prise en charge et son inclusion dans leur pratique, et les moyens qu’ils privilégieraient pour valoriser cet aspect de la pratique. Résultats Au total, 289 médecins résidents ont rempli le questionnaire (38,7 %). De ce nombre, 201 répondants ont indiqué qu’ils anticipaient faire de la prise en charge dans leurs 5 premières années de pratique. Les facteurs inhibitifs les plus soulignés dans la section commentaires sont la difficulté à quitter la pratique, la complexité des cas et les responsabilités face au suivi du patient. Les plans régionaux d’effectifs médicaux et les activités médicales particulières ne sont pas ressortis de manière significative comme facteurs inhibitifs. Selon les répondants, la valorisation de la médecine familiale devrait passer par la promotion auprès des étudiants en médecine, par une modification de la culture institutionnelle et par une augmentation de la visibilité des médecins résidents et des patrons en médecine familiale au sein des équipes dans les milieux de formation. Conclusion Cette étude permet de conclure que les médecins résidents québécois prévoient inclure la prise en charge dans leur pratique. Toutefois, des solutions tangibles doivent être établies pour mitiger le poids de la pratique en cabinet et continuer à promouvoir la prise en charge auprès des jeunes médecins de famille.

  9. Novel modification of voice prosthesis.

    PubMed

    Al Kadah, Basel; Papaspyrou, George; Schneider, Mathias; Schick, Bernhard

    2016-03-01

    The undesired dilatation of the tracheooesophageal shunt after surgical implantation of voice prosthesis is a typical complication of this procedure. Temporary removal of the prosthesis and reinsertion after a short period of time is a first-line therapeutical option aiming shrinkage of the shunt. Failure of this measure generally is an indication of revision surgery. We present first experiences treating leakage problems with novel modified voice prosthesis without surgical intervention in specified cases. 11 patients (1 female, 10 male) aging between 51 and 71 years were presented with shunt leakage between 11/2008 and 11/2012 in the ENT-Department of the University Hospital of Homburg/Saar after a custom built voice prosthesis had been used initially successfully. A "Provox 2"(®) voice prosthesis was modified with two discs made of silicone each on the tracheal and oesophageal side and additionally reinforcing the diameter of the prosthesis by a silicone tube. The modified prosthesis was inserted in a retrograde way under general anesthesia, analogical to the approach used with the "Provox 1"(®)-prosthesis. The period of observation ranged between 12 and 48 months. As a measure of control swallowing of methylene blue was used. In all cases leakage suspended. Durability of the modified prosthesis ranged between 2 and 6 months. Neither the patients' complained about, nor did the physicians notice subjectively an impairment of the voice quality. Modifications of "Provox 2"(®)-prosthesis should be regarded in individual cases and constitute a reasonable alternative to revision surgery. A surgical approach is more intricate and costly, more taxing for the patient and susceptible to failure. We regard the necessity of general anesthesia for the insertion of the modified prosthesis as a disadvantage.

  10. Wind Farms and Weather Modification.

    NASA Astrophysics Data System (ADS)

    Barrie, D. B.; Kirk-Davidoff, D. B.

    2008-12-01

    Electrical generation by wind turbines is increasing rapidly, and has been projected to satisfy 15 percent of world electric demand by 2030. The extensive installation of wind farms would alter surface roughness and significantly impact the atmospheric circulation. This forcing could be changed deliberately by adjusting the attitude of the turbine blades with respect to the wind. Using the NCAR Community Atmosphere Model, we model the impact of time-dependent surface roughness changes due to manipulation of a continent-scale wind farm. We show that initial disturbances caused by a step change in roughness grow within four days such that the flow is altered at synoptic scales. The growth rate of the induced perturbations is largest in regions of high atmospheric instability. For a roughness change imposed over North America, the induced perturbations involve substantial changes in the track and development of cyclones over the North Atlantic. For example, in some cases, weather over the British Isles changes from cloudy to clear, depending on whether wind turbines in the American Midwest are "on" or "off" three days beforehand. We explore the dependence of the downstream effects on the size and roughness of the wind farm installation, showing that as the size of individual wind farms and turbines grows, the scale of atmospheric impacts increases in extent and magnitude. We also look at the dependence of the wind farm impacts on the initial state of the atmosphere, confirming that the impacts are largest when the wind farm perturbation projects onto growing error modes in the atmosphere. In particular, rapid growth occurs when the initial disturbance is carried into regions of high baroclinic instability such as the North Atlantic. By running ensemble experiments, we estimate the robustness of the wind farm impacts with respect to realistic uncertainty in the initial conditions. Our results suggest the possibility of a method for weather modification that in some

  11. [Behavior modification therapy: application in renal nursing].

    PubMed

    Wang, Lu-Mei; Hung, Shih-Yuan; Chiou, Chou-Ping

    2011-04-01

    Kidney patients often suffer numerous comorbidities (e.g., hyperphosphatemia, renal osteodystrophy, and bodyweight gain induced by fluid overload or hypertension), which often impart discomfort and a significantly reduced quality of life. The literatures points to the efficacy of behavior modification therapy in changing inappropriate self-health care behavior in order to improve comorbidity symptoms. This article introduces behavior modification theory and its application as well as clinical strategies related to kidney patient care. The authors hope this article will promote knowledge of behavior modification theory among healthcare professionals and facilitate to the application of this theory in clinical practice to improve nursing care.

  12. Global Post-Translational Modification Discovery.

    PubMed

    Li, Qiyao; Shortreed, Michael R; Wenger, Craig D; Frey, Brian L; Schaffer, Leah V; Scalf, Mark; Smith, Lloyd M

    2017-03-01

    A new global post-translational modification (PTM) discovery strategy, G-PTM-D, is described. A proteomics database containing UniProt-curated PTM information is supplemented with potential new modification types and sites discovered from a first-round search of mass spectrometry data with ultrawide precursor mass tolerance. A second-round search employing the supplemented database conducted with standard narrow mass tolerances yields deep coverage and a rich variety of peptide modifications with high confidence in complex unenriched samples. The G-PTM-D strategy represents a major advance to the previously reported G-PTM strategy and provides a powerful new capability to the proteomics research community.

  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. 47 CFR 25.118 - Modifications not requiring prior authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....118 Modifications not requiring prior authorization. (a) Earth station license modifications, notification required. Authorized earth station operators may make the following modifications to their... of part 1, subpart Y of this chapter: (1) Licensees may make changes to their authorized...

  19. 47 CFR 25.118 - Modifications not requiring prior authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....118 Modifications not requiring prior authorization. (a) Earth station license modifications, notification required. Authorized earth station operators may make the following modifications to their... of part 1, subpart Y of this chapter: (1) Licensees may make changes to their authorized...

  20. 47 CFR 25.118 - Modifications not requiring prior authorization.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....118 Modifications not requiring prior authorization. (a) Earth station license modifications, notification required. Authorized earth station operators may make the following modifications to their... of part 1, subpart Y of this chapter: (1) Licensees may make changes to their authorized...

  1. 47 CFR 25.118 - Modifications not requiring prior authorization.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ....118 Modifications not requiring prior authorization. (a) Earth station license modifications, notification required. Authorized earth station operators may make the following modifications to their... of part 1, subpart Y of this chapter: (1) Licensees may make changes to their authorized...

  2. 47 CFR 25.118 - Modifications not requiring prior authorization.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....118 Modifications not requiring prior authorization. (a) Earth station license modifications, notification required. Authorized earth station operators may make the following modifications to their... of part 1, subpart Y of this chapter: (1) Licensees may make changes to their authorized...

  3. 40 CFR 60.397 - Modifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Coating Operations § 60.397 Modifications. The following physical or operational changes are not, by... changeovers or switches to larger cars. (b) Changes in the application of the coatings to increase...

  4. Histone Modifications and Nuclear Architecture: A Review

    PubMed Central

    Bártová, Eva; Krejčí, Jana; Harničarová, Andrea; Galiová, Gabriela; Kozubek, Stanislav

    2008-01-01

    Epigenetic modifications, such as acetylation, phosphorylation, methylation, ubiquitination, and ADP ribosylation, of the highly conserved core histones, H2A, H2B, H3, and H4, influence the genetic potential of DNA. The enormous regulatory potential of histone modification is illustrated in the vast array of epigenetic markers found throughout the genome. More than the other types of histone modification, acetylation and methylation of specific lysine residues on N-terminal histone tails are fundamental for the formation of chromatin domains, such as euchromatin, and facultative and constitutive heterochromatin. In addition, the modification of histones can cause a region of chromatin to undergo nuclear compartmentalization and, as such, specific epigenetic markers are non-randomly distributed within interphase nuclei. In this review, we summarize the principles behind epigenetic compartmentalization and the functional consequences of chromatin arrangement within interphase nuclei. (J Histochem Cytochem 56:711–721, 2008) PMID:18474937

  5. Assessment of posttranslational modification of mitochondrial proteins.

    PubMed

    Ande, Sudharsana R; Padilla-Meier, G Pauline; Mishra, Suresh

    2015-01-01

    Mitochondria play vital roles in the maintenance of cellular homeostasis. They are a storehouse of cellular energy and antioxidative enzymes. Because of its immense role and function in the development of an organism, this organelle is required for the survival. Defects in mitochondrial proteins lead to complex mitochondrial disorders and heterogeneous diseases such as cancer, type 2 diabetes, and cardiovascular and neurodegenerative diseases. It is widely known in the literature that some of the mitochondrial proteins are regulated by posttranslational modifications. Hence, designing methods to assess these modifications in mitochondria will be an important way to study the regulatory roles of mitochondrial proteins in greater detail. In this chapter, we outlined procedures to isolate mitochondria from cells and separate the mitochondrial proteins by two-dimensional gel electrophoresis and identify the different posttranslational modifications in them by using antibodies specific to each posttranslational modification.

  6. Surface Modification of Water Purification Membranes.

    PubMed

    Miller, Daniel J; Dreyer, Daniel R; Bielawski, Christopher W; Paul, Donald R; Freeman, Benny D

    2017-04-18

    Polymeric membranes are an energy-efficient means of purifying water, but they suffer from fouling during filtration. Modification of the membrane surface is one route to mitigating membrane fouling, as it helps to maintain high levels of water productivity. Here, a series of common techniques for modification of the membrane surface are reviewed, including surface coating, grafting, and various treatment techniques such as chemical treatment, UV irradiation, and plasma treatment. Historical background on membrane development and surface modification is also provided. Finally, polydopamine, an emerging material that can be easily deposited onto a wide variety of substrates, is discussed within the context of membrane modification. A brief summary of the chemistry of polydopamine, particularly as it may pertain to membrane development, is also described.

  7. The computational nature of memory modification.

    PubMed

    Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

    2017-03-15

    Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature.

  8. Sustainable environmental nanotechnology using nanoparticle surface modification.

    EPA Science Inventory

    Reactive nanomaterials used for environmental remediation require surface modification to make them mobile in the subsurface. Nanomaterials released into the environment inadvertently without an engineered surface coating will acquire one (e.g. adsorption of natural organic matt...

  9. 7 CFR 1467.13 - Modifications.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... amended easement, which is duly prepared and recorded in conformity with standard real estate practices... consistent with the easement and applicable law, the State Conservationist may approve modifications to...

  10. Germline Modification and Engineering in Avian Species.

    PubMed

    Lee, Hong Jo; Lee, Hyung Chul; Han, Jae Yong

    2015-09-01

    Production of genome-edited animals using germline-competent cells and genetic modification tools has provided opportunities for investigation of biological mechanisms in various organisms. The recently reported programmed genome editing technology that can induce gene modification at a target locus in an efficient and precise manner facilitates establishment of animal models. In this regard, the demand for genome-edited avian species, which are some of the most suitable model animals due to their unique embryonic development, has also increased. Furthermore, germline chimera production through long-term culture of chicken primordial germ cells (PGCs) has facilitated research on production of genome-edited chickens. Thus, use of avian germline modification is promising for development of novel avian models for research of disease control and various biological mechanisms. Here, we discuss recent progress in genome modification technology in avian species and its applications and future strategies.

  11. 40 CFR 72.81 - Permit modifications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... compliance deadline extension; and (5) Changes in a thermal energy plan that result in any addition or... replacement of thermal energy. (c)(1) Permit modifications shall follow the permit issuance requirements...

  12. 40 CFR 72.81 - Permit modifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... compliance deadline extension; and (5) Changes in a thermal energy plan that result in any addition or... replacement of thermal energy. (c)(1) Permit modifications shall follow the permit issuance requirements...

  13. 40 CFR 72.81 - Permit modifications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... compliance deadline extension; and (5) Changes in a thermal energy plan that result in any addition or... replacement of thermal energy. (c)(1) Permit modifications shall follow the permit issuance requirements...

  14. Current status on plastic scintillators modifications.

    PubMed

    Bertrand, Guillaume H V; Hamel, Matthieu; Sguerra, Fabien

    2014-11-24

    Recent developments of plastic scintillators are reviewed, from 2000 to March 2014, distributed in two different chapters. First chapter deals with the chemical modifications of the polymer backbone, whereas modifications of the fluorescent probe are presented in the second chapter. All examples are provided with the scope of detection of various radiation particles. The main characteristics of these newly created scintillators and their detection properties are given.

  15. Surface modification agents for lithium batteries

    DOEpatents

    Chen, Zonghai; Amine, Khalil; Belharouak, Ilias

    2015-06-23

    A method includes modifying a surface of an electrode active material including providing a solution or a suspension of a surface modification agent; providing the electrode active material; preparing a slurry of the solution or suspension of the surface modification agent, the electrode active material, a polymeric binder, and a conductive filler; casting the slurry in a metallic current collector; and drying the cast slurry.

  16. Cytosine modifications in neurodevelopment and diseases

    PubMed Central

    Yao, Bing; Jin, Peng

    2013-01-01

    DNA methylation has been studied comprehensively and linked to both normal neurodevelopment and neurological diseases. The recent identification of several new DNA modifications, including 5-hydroxylmethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), has given us a new perspective on the previously observed plasticity in 5mC-dependent regulatory processes. Here we review the latest research into these cytosine modifications, focusing mainly on their roles in neurodevelopment and diseases. PMID:23912899

  17. 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.

  18. Detection of histone modifications in plant leaves.

    PubMed

    Jaskiewicz, Michal; Peterhansel, Christoph; Conrath, Uwe

    2011-09-23

    Chromatin structure is important for the regulation of gene expression in eukaryotes. In this process, chromatin remodeling, DNA methylation, and covalent modifications on the amino-terminal tails of histones H3 and H4 play essential roles(1-2). H3 and H4 histone modifications include methylation of lysine and arginine, acetylation of lysine, and phosphorylation of serine residues(1-2). These modifications are associated either with gene activation, repression, or a primed state of gene that supports more rapid and robust activation of expression after perception of appropriate signals (microbe-associated molecular patterns, light, hormones, etc.)(3-7). Here, we present a method for the reliable and sensitive detection of specific chromatin modifications on selected plant genes. The technique is based on the crosslinking of (modified) histones and DNA with formaldehyde(8,9), extraction and sonication of chromatin, chromatin immunoprecipitation (ChIP) with modification-specific antibodies(9,10), de-crosslinking of histone-DNA complexes, and gene-specific real-time quantitative PCR. The approach has proven useful for detecting specific histone modifications associated with C(4;) photosynthesis in maize(5,11) and systemic immunity in Arabidopsis(3).

  19. Epigenetic Modifications of Histones in Periodontal Disease.

    PubMed

    Martins, M D; Jiao, Y; Larsson, L; Almeida, L O; Garaicoa-Pazmino, C; Le, J M; Squarize, C H; Inohara, N; Giannobile, W V; Castilho, R M

    2016-02-01

    Periodontitis is a chronic infectious disease driven by dysbiosis, an imbalance between commensal bacteria and the host organism. Periodontitis is a leading cause of tooth loss in adults and occurs in about 50% of the US population. In addition to the clinical challenges associated with treating periodontitis, the progression and chronic nature of this disease seriously affect human health. Emerging evidence suggests that periodontitis is associated with mechanisms beyond bacteria-induced protein and tissue degradation. Here, we hypothesize that bacteria are able to induce epigenetic modifications in oral epithelial cells mediated by histone modifications. In this study, we found that dysbiosis in vivo led to epigenetic modifications, including acetylation of histones and downregulation of DNA methyltransferase 1. In addition, in vitro exposure of oral epithelial cells to lipopolysaccharides resulted in histone modifications, activation of transcriptional coactivators, such as p300/CBP, and accumulation of nuclear factor-κB (NF-κB). Given that oral epithelial cells are the first line of defense for the periodontium against bacteria, we also evaluated whether activation of pathogen recognition receptors induced histone modifications. We found that activation of the Toll-like receptors 1, 2, and 4 and the nucleotide-binding oligomerization domain protein 1 induced histone acetylation in oral epithelial cells. Our findings corroborate the emerging concept that epigenetic modifications play a role in the development of periodontitis.

  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. Disease modification in Parkinson's disease.

    PubMed

    Henchcliffe, Claire; Severt, W Lawrence

    2011-08-01

    pragmatically tests whether earlier versus later intervention is beneficial. If positive (i.e. if an earlier intervention proves more effective), this demonstrates disease modification, which could result from neuroprotection or from other mechanisms. This strategy therefore provides a first step towards supporting neuroprotection in PD. Of the three delayed-start design clinical trials, two have investigated early versus later start of rasagiline, a specific irreversible monoamine oxidase B inhibitor. Each trial has supported, although not proven, disease-modifying effects. A third delayed-start-design clinical trial examining potential disease-modifying effects of pramipexole has unfortunately reportedly been negative according to preliminary presentations. The suggestion that rasagiline is disease modifying is made all the more compelling by in vitro and PD animal-model studies in which rasagiline was shown to have neuroprotective effects. In this review, we examine efforts to demonstrate neuroprotection in PD to date, describe ongoing neuroprotection trials, and critically discuss the results of the most recent delayed-start clinical trials that test possible disease-modifying activities of rasagiline and pramipexole in PD.

  2. 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

  3. 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

  4. 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).

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. 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).

  10. Enzymatic modifications of exopolysaccharides enhance bacterial persistence

    PubMed Central

    Whitfield, Gregory B.; Marmont, Lindsey S.; Howell, P. Lynne

    2015-01-01

    Biofilms are surface-attached communities of bacterial cells embedded in a self-produced matrix that are found ubiquitously in nature. The biofilm matrix is composed of various extracellular polymeric substances, which confer advantages to the encapsulated bacteria by protecting them from eradication. The matrix composition varies between species and is dependent on the environmental niche that the bacteria inhabit. Exopolysaccharides (EPS) play a variety of important roles in biofilm formation in numerous bacterial species. The ability of bacteria to thrive in a broad range of environmental settings is reflected in part by the structural diversity of the EPS produced both within individual bacterial strains as well as by different species. This variability is achieved through polymerization of distinct sugar moieties into homo- or hetero-polymers, as well as post-polymerization modification of the polysaccharide. Specific enzymes that are unique to the production of each polymer can transfer or remove non-carbohydrate moieties, or in other cases, epimerize the sugar units. These modifications alter the physicochemical properties of the polymer, which in turn can affect bacterial pathogenicity, virulence, and environmental adaptability. Herein, we review the diversity of modifications that the EPS alginate, the Pel polysaccharide, Vibrio polysaccharide, cepacian, glycosaminoglycans, and poly-N-acetyl-glucosamine undergo during biosynthesis. These are EPS produced by human pathogenic bacteria for which studies have begun to unravel the effect modifications have on their physicochemical and biological properties. The biological advantages these polymer modifications confer to the bacteria that produce them will be discussed. The expanding list of identified modifications will allow future efforts to focus on linking these modifications to specific biosynthetic genes and biofilm phenotypes. PMID:26029200

  11. 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

  12. [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.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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.

  20. Sequence tagging reveals unexpected modifications in toxicoproteomics.

    PubMed

    Dasari, Surendra; Chambers, Matthew C; Codreanu, Simona G; Liebler, Daniel C; Collins, Ben C; Pennington, Stephen R; Gallagher, William M; Tabb, David L

    2011-02-18

    Toxicoproteomic samples are rich in posttranslational modifications (PTMs) of proteins. Identifying these modifications via standard database searching can incur significant performance penalties. Here, we describe the latest developments in TagRecon, an algorithm that leverages inferred sequence tags to identify modified peptides in toxicoproteomic data sets. TagRecon identifies known modifications more effectively than the MyriMatch database search engine. TagRecon outperformed state of the art software in recognizing unanticipated modifications from LTQ, Orbitrap, and QTOF data sets. We developed user-friendly software for detecting persistent mass shifts from samples. We follow a three-step strategy for detecting unanticipated PTMs in samples. First, we identify the proteins present in the sample with a standard database search. Next, identified proteins are interrogated for unexpected PTMs with a sequence tag-based search. Finally, additional evidence is gathered for the detected mass shifts with a refinement search. Application of this technology on toxicoproteomic data sets revealed unintended cross-reactions between proteins and sample processing reagents. Twenty-five proteins in rat liver showed signs of oxidative stress when exposed to potentially toxic drugs. These results demonstrate the value of mining toxicoproteomic data sets for modifications.

  1. Structural investigation into physiological DNA phosphorothioate modification

    PubMed Central

    Lan, Wenxian; Hu, Zhongpei; Shen, Jie; Wang, Chunxi; Jiang, Feng; Liu, Huili; Long, Dewu; Liu, Maili; Cao, Chunyang

    2016-01-01

    DNA phosphorothioate (PT) modification, with sulfur replacing a nonbridging phosphate oxygen in a sequence and stereo specific manner, is a novel physiological variation in bacteria. But what effects on DNA properties PT modification has is still unclear. To address this, we prepared three double-stranded (ds) DNA decamers, d(CGPXGCCGCCGA) with its complementary strand d(TCGGCGPXGCCG) (where X = O or S, i.e., PT-free dsDNA, [Sp, Sp]-PT dsDNA or [Rp, Rp]-PT dsDNA) located in gene of Streptomyces lividans. Their melting temperature (Tm) measurement indicates that [Rp, Rp]-PT dsDNA is most unstable. Their electron transfer potential detection presents an order of anti-oxidation properties: Sp-PT DNA > Rp-PT DNA > PT-free DNA. Their NMR structures demonstrate that PT modification doesn’t change their B-form conformation. The sulfur in [Rp, Rp]-PT dsDNA locates in the major groove, with steric effects on protons in the sugar close to modification sites, resulting in its unstability, and facilitating its selectively interactions with ScoMcrA. We thought that PT modification was dialectical to the bacteria. It protects the hosting bacteria by working as antioxidant against H2O2, and acts as a marker, directing restriction enzyme observed in other hosts, like ScoMcrA, to correctly cleave the PT modified DNA, so that bacteria cannot spread and survive. PMID:27169778

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Modification site localization scoring: strategies and performance.

    PubMed

    Chalkley, Robert J; Clauser, Karl R

    2012-05-01

    Using enrichment strategies many research groups are routinely producing large data sets of post-translationally modified peptides for proteomic analysis using tandem mass spectrometry. Although search engines are relatively effective at identifying these peptides with a defined measure of reliability, their localization of site/s of modification is often arbitrary and unreliable. The field continues to be in need of a widely accepted metric for false localization rate that accurately describes the certainty of site localization in published data sets and allows for consistent measurement of differences in performance of emerging scoring algorithms. In this article are discussed the main strategies currently used by software for modification site localization and ways of assessing the performance of these different tools. Methods for representing ambiguity are reviewed and a discussion of how the approaches transfer to different data types and modifications is presented.

  7. [Epigenic modifications associated with low benzene exposure].

    PubMed

    Fustinoni, Silvia; Bollati, Valentina; Bertazzi, Pier Alberto

    2013-01-01

    DNA methylation, mitochondrial DNA copy number and telomeres shortening are cellular modifications associated with an increasing number of tumors, cardiovascular and aging diseases. In our studies these modifications were evaluated in subjects occupationally exposed to low levels of benzene and in the general population. In peripheral blood lymphocytes a decrease of DNA methylation with the increase of personal benzene exposure was found, both in Alu and LINE-1 repetitive elements, and in the global DNA. Telomere length shortening in subjects exposed to traffic exhausts and an increase in mitochondrial DNA copy number correlated to benzene exposure was also found. DNA methylation measured in specimen repeats collected at intervals of 8 years decreased more markedly in exposed subjects than in controls. Our studies highlighted the association of epigenetic modifications of DNA with low benzene exposure.

  8. Global Post-Translational Modification Discovery

    PubMed Central

    2016-01-01

    A new global post-translational modification (PTM) discovery strategy, G-PTM-D, is described. A proteomics database containing UniProt-curated PTM information is supplemented with potential new modification types and sites discovered from a first-round search of mass spectrometry data with ultrawide precursor mass tolerance. A second-round search employing the supplemented database conducted with standard narrow mass tolerances yields deep coverage and a rich variety of peptide modifications with high confidence in complex unenriched samples. The G-PTM-D strategy represents a major advance to the previously reported G-PTM strategy and provides a powerful new capability to the proteomics research community. PMID:28248113

  9. 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.

  10. 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.

  11. NASTRAN modifications for recovering strains and curvatures

    NASA Technical Reports Server (NTRS)

    Hennrich, C. W.

    1975-01-01

    Modifications to the NASTRAN structural analysis computer program are described. The modifications allow the recovery of strain and curvature data for the general two-dimensional elements, in addition to the usual stress data. Option features allow the transformation of the strain/curvature (or stress) data to a common coordinate system and representation at the grid points of the structural model rather than at the conventional element center locations. Usage information is provided which will allow present users of NASTRAN to easily utilize the new capability.

  12. Modeling the dynamics of bivalent histone modifications.

    PubMed

    Ku, Wai Lim; Girvan, Michelle; Yuan, Guo-Cheng; Sorrentino, Francesco; Ott, Edward

    2013-01-01

    Epigenetic modifications to histones may promote either activation or repression of the transcription of nearby genes. Recent experimental studies show that the promoters of many lineage-control genes in stem cells have "bivalent domains" in which the nucleosomes contain both active (H3K4me3) and repressive (H3K27me3) marks. It is generally agreed that bivalent domains play an important role in stem cell differentiation, but the underlying mechanisms remain unclear. Here we formulate a mathematical model to investigate the dynamic properties of histone modification patterns. We then illustrate that our modeling framework can be used to capture key features of experimentally observed combinatorial chromatin states.

  13. Development of an Improved Permeability Modification Simulator

    SciTech Connect

    Gao, H.W.; Elphnick, J.

    1999-03-09

    This report describes the development of an improved permeability modification simulator performed jointly by BDM Petroleum Technologies and Schlumberger Dowell under a cooperative research and development agreement (CRADA) with the US Department of Energy. The improved simulator was developed by modifying NIPER's PC-GEL permeability modification simulator to include a radial model, a thermal energy equation, a wellbore simulator, and a fully implicit time-stepping option. The temperature-dependent gelation kinetics of a delayed gel system (DGS) is also included in the simulator.

  14. Surface modification to prevent oxide scale spallation

    DOEpatents

    Stephens, Elizabeth V; Sun, Xin; Liu, Wenning; Stevenson, Jeffry W; Surdoval, Wayne; Khaleel, Mohammad A

    2013-07-16

    A surface modification to prevent oxide scale spallation is disclosed. The surface modification includes a ferritic stainless steel substrate having a modified surface. A cross-section of the modified surface exhibits a periodic morphology. The periodic morphology does not exceed a critical buckling length, which is equivalent to the length of a wave attribute observed in the cross section periodic morphology. The modified surface can be created using at least one of the following processes: shot peening, surface blasting and surface grinding. A coating can be applied to the modified surface.

  15. Modification of gravity due to torsion

    SciTech Connect

    Nair, V. P.; Nikiforova, V.; Randjbar-Daemi, S.; Rubakov, V.

    2010-01-01

    Modifications of general relativity have been considered as one of the possible ways of addressing some of the outstanding problems related to the large scale gravitational physics. In this contribution we review some of the recent results which are due to the inclusion of dynamical torsion. More specifically we shall discuss the propagation of massive spin-2 particles in flat and curved space times. We shall show that, contrary to what is generally believed, spinning matter is not the sole source of torsion field. A symmetric energy momentum tensor can also couple to torsion degrees of freedom. The massive and massless spin-2 particles mix giving rise to an infrared modification of gravity.

  16. Oxygen from Hydrogen Peroxide: An Experimental Modification

    NASA Astrophysics Data System (ADS)

    Burness, James H.

    1996-09-01

    A common experiment, performed at the high school and college levels, is the generation of a gas to explore molar mass and molar volume relationships. In one version of this experiment, hydrogen peroxide is decomposed by yeast to generate oxygen gas. This paper describes a simple modification to this experiment which eliminates the need for a pencil coated with petroleum jelly and dry yeast. This elimination not only prevents falling pieces of yeast from prematurely starting the reaction, but at the same time makes the reaction faster and simplifies cleanup. The modification also reduces the likelihood of cuts from broken tubing.

  17. 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

  18. 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.

  19. Conformational and biological properties of the Ala10 analogue of human des-Trp1,Nle12-minigastrin.

    PubMed

    Mammi, S; Foffani, M T; Peggion, E; Galleyrand, J C; Bali, J P; Simonetti, M; Göhring, W; Moroder, L; Wünsch, E

    1989-09-05

    Synthesis, conformation, and biological properties of the Ala10 analogue of des-Trp1,Nle12-minigastrin are reported. Replacement of the Gly residue in the original sequence with Ala remarkably changes the conformational preference of the hormone in trifluoroethanol. CD and NMR results indicate that the conformational change is mainly located in the C-terminal portion of the molecule, with probable extension of the N-terminal alpha-helix throughout the entire sequence. The structural modification causes a 10-fold decrease in the biological potency of the hormone, which is about as active as the C-terminal tetrapeptide amide. These findings support our previous hypothesis that the optimal bioactive conformation of the native hormone is U-shaped, with mutual interactions among the two end segments.

  20. 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.

  1. 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).

  2. Tracking epigenetic histone modifications in single cells using Fab-based live endogenous modification labeling.

    PubMed

    Hayashi-Takanaka, Yoko; Yamagata, Kazuo; Wakayama, Teruhiko; Stasevich, Timothy J; Kainuma, Takashi; Tsurimoto, Toshiki; Tachibana, Makoto; Shinkai, Yoichi; Kurumizaka, Hitoshi; Nozaki, Naohito; Kimura, Hiroshi

    2011-08-01

    Histone modifications play an important role in epigenetic gene regulation and genome integrity. It remains largely unknown, however, how these modifications dynamically change in individual cells. By using fluorescently labeled specific antigen binding fragments (Fabs), we have developed a general method to monitor the distribution and global level of endogenous histone H3 lysine modifications in living cells without disturbing cell growth and embryo development. Fabs produce distinct nuclear patterns that are characteristic of their target modifications. H3K27 trimethylation-specific Fabs, for example, are concentrated on inactive X chromosomes. As Fabs bind their targets transiently, the ratio of bound and free molecules depends on the target concentration, allowing us to measure changes in global modification levels. High-affinity Fabs are suitable for mouse embryo imaging, so we have used them to monitor H3K9 and H3K27 acetylation levels in mouse preimplantation embryos produced by in vitro fertilization and somatic cell nuclear transfer. The data suggest that a high level of H3K27 acetylation is important for normal embryo development. As Fab-based live endogenous modification labeling (FabLEM) is broadly useful for visualizing any modification, it should be a powerful tool for studying cell signaling and diagnosis in the future.

  3. Renormalisation des theories de champs non commutatives

    NASA Astrophysics Data System (ADS)

    Vignes-Tourneret, Fabien

    2006-12-01

    Very high energy physics needs a coherent description of the four fundamental forces. Non-commutative geometry is a promising mathematical framework which already allowed to unify the general relativity and the standard model, at the classical level, thanks to the spectral action principle. Quantum field theories on non-commutative spaces is a first step towards the quantification of such a model. These theories can't be obtained simply by writing usual field theory on non-commutative spaces. Such attempts exhibit indeed a new type of divergencies, called ultraviolet/infrared mixing, which prevents renormalisability. H. Grosse and R. Wulkenhaar showed, with an example, that a modification of the propagator may restore renormalisability. This thesis aims at studying the generalization of such a method. We studied two different models which allowed to specify certain aspects of non-commutative field theory. In x space, the major technical difficulty is due to oscillations in the interaction part. We generalized the results of T. Filk in order to exploit such oscillations at best. We were then able to distinguish between two mixings, renormalizable or not. We also bring the notion of orientability to light : the orientable non-commutative Gross-Neveu model is renormalizable without any modification of its propagator. The adaptation of multi-scale analysis to the matrix basis emphasized the importance of dual graphs and represents a first step towards a formulation of field theory independent of the underlying space.

  4. 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

  5. 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

  6. 40 CFR 60.14 - Modification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PERFORMANCE FOR NEW STATIONARY SOURCES General Provisions § 60.14 Modification. (a) Except as provided under... facility to a stationary source as an expansion to that source or as a replacement for an existing facility shall not by itself bring within the applicability of this part any other facility within that...

  7. Adaptive size modification by dominant female meerkats.

    PubMed

    Russell, Andrew F; Carlson, Anne A; McIlrath, Grant M; Jordan, Neil R; Clutton-Brock, Tim

    2004-07-01

    In species of cooperative insects that live in large groups, selection for increased fecundity has led to the evolution of an increased body size among female reproductives, but whether this is also true of cooperative vertebrates is unknown. Among vertebrates, morphological modification of female breeders has only been documented in a single species; in naked mole rats (Heterocephalus glaber), acquisition of alpha status is associated with a significant increase in body size through an elongation of the lumbar vertebrae. Here we provide evidence of morphological modification among breeding females of a cooperative carnivore, the meerkat (Suricata suricatta), and demonstrate that this modification is likely to be adaptive. The same female meerkats were significantly larger when they were dominant than when they were subordinate. This increased body size was not explained by differences in age, foraging efficiency, or investment in offspring care, but may have arisen, in part, through increased levels of hormone that govern bone growth. Increases in body size are likely to result in fitness benefits, for large females delivered larger litters and had heavier offspring, both of which are known to correlate positively with measures of breeding success in meerkats. Our results suggest that the acquisition of alpha status in female meerkats is associated with an adaptive increase in body size and hence that morphological modification of female vertebrates may be more widespread than has been previously supposed.

  8. Modifications of the Test Information Function.

    ERIC Educational Resources Information Center

    Samejima, Fumiko

    Two modification formulas are presented for the test information function in order to provide better measures of local accuracies of the estimation of "theta" when maximum likelihood estimation is used to provide the estimate of ability "theta." A minimum bound of any estimator, biased or unbiased, is considered; and Formula 1…

  9. Oxidative modifications of mitochondria complex II.

    PubMed

    Zhang, Liwen; Kang, Patrick T; Chen, Chwen-Lih; Green, Kari B; Chen, Yeong-Renn

    2013-01-01

    Increased superoxide (O2 (·-)) and nitric oxide (NO) production is a key mechanism of mitochondrial dysfunction in myocardial ischemia/reperfusion injury. In the complex II, oxidative impairment, decreased protein S-glutathionylation, and increased protein tyrosine nitration at the 70 kDa subunit occur in the post-ischemic myocardium (Zhang et al., Biochemistry 49:2529-2539, 2010; Chen et al., J Biol Chem 283:27991-28003, 2008; Chen et al., J Biol Chem 282: 32640-32654, 2007). To gain the deeper insights into ROS-mediated oxidative modifications relevant in myocardial infarction, isolated complex II is subjected to in vitro oxidative modifications with GSSG (to induce cysteine S-glutathionylation) or OONO(-) (to induce tyrosine nitration). Here, we describe the protocol to characterize the specific oxidative modifications at the 70 kDa subunit by nano-LC/MS/MS analysis. We further demonstrate the cellular oxidative modification with protein nitration/S-glutathionylation with immunofluorescence microscopy using the antibodies against 3-nitrotyrosine/glutathione and complex II 70 kDa polypeptide (AbGSC90) in myocytes under conditions of oxidative stress.

  10. 21 CFR 352.77 - Test modifications.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Test modifications. 352.77 Section 352.77 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE SUNSCREEN DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE Testing Procedures § 352.77...

  11. A Modification to Maxwell's Needle Apparatus

    ERIC Educational Resources Information Center

    Soorya, Tribhuvan N.

    2015-01-01

    Maxwell's needle apparatus is used to determine the shear modulus (?) of the material of a wire of uniform cylindrical cross section. Conventionally, a single observation is taken for each observable, and the value of ? is calculated in a single shot. A modification to the above apparatus is made by varying one of the observables, namely the mass…

  12. Chemical Modification of Nanotubes for Composites

    NASA Technical Reports Server (NTRS)

    Samulski, Edward T.

    2003-01-01

    In the production of mesoscopically-engineered materials based on single-walled carbon nanotubes (SWNTs), monitoring the stages of chemical modification will be an important step in the fabrication of usable composite materials. In our research program we developed tools for studying high-temperature composites with a long-term goal of having such instrumentation available for SWNT composite analyses.

  13. 24 CFR 203.342 - Mortgage modification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Mortgage modification. 203.342 Section 203.342 Housing and Urban Development Regulations Relating to Housing and Urban...

  14. 24 CFR 203.342 - Mortgage modification.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Mortgage modification. 203.342 Section 203.342 Housing and Urban Development Regulations Relating to Housing and Urban...

  15. 24 CFR 203.342 - Mortgage modification.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Mortgage modification. 203.342 Section 203.342 Housing and Urban Development Regulations Relating to Housing and Urban...

  16. 24 CFR 203.342 - Mortgage modification.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Mortgage modification. 203.342 Section 203.342 Housing and Urban Development Regulations Relating to Housing and Urban...

  17. 24 CFR 203.342 - Mortgage modification.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Mortgage modification. 203.342 Section 203.342 Housing and Urban Development Regulations Relating to Housing and Urban...

  18. 40 CFR 147.2927 - Permit modification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Permit modification. 147.2927 Section 147.2927 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) STATE, TRIBAL, AND EPA-ADMINISTERED UNDERGROUND INJECTION CONTROL PROGRAMS Osage Mineral...

  19. Behavior Modification of Retarded Preschool Children.

    ERIC Educational Resources Information Center

    Yamaguchi, Kaoru

    1977-01-01

    In a study of behavior modification two Down's syndrome preschool children, the first a 5-year-old boy with autistic behavior patterns and the second a 4-year-old girl whose behavior problem was to reject other children, were examined. The first S was engaged in ball catching activities with a teacher with positive reinforcement (playing the S's…

  20. Modification of Behavior: Application in Classroom Management.

    ERIC Educational Resources Information Center

    Ille, Sister Janiece; Bezzi, D. R.

    The emphasis of this research report was on modification of classroom behavior. After a brief introduction, the two main learning theories of Gestalt-field psychology and stimulus-response association were investigated. The importance of the individual in modifying his own behavior was stressed in Gestalt-field psychology. The importance of…

  1. D-21B RBCC Modification Feasibility Study

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report presents a feasibility study on the modifications required to re-engine the Lockheed D-21 Drone for use as a NASA RBCC engine. An introduction, background information, engine configuration and performance, propulsion system integration, loads/thermal analysis, avionics/systems, flight test results, costs and work schedule, and some conclusions are presented.

  2. How to Train Supervisors in Behavior Modification.

    ERIC Educational Resources Information Center

    Arkin, Ronald; And Others

    This is a guide for training supervisors in the theory and application of behavior modification using material that has been implemented successfully for many years in companies throughout the country. Procedures for organizing and conducting training sessions in a supervisor training program are presented. The manual, one of four prepared to aid…

  3. 7 CFR 623.14 - Easement modifications.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Easement modifications. 623.14 Section 623.14 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE WATER RESOURCES EMERGENCY WETLANDS RESERVE PROGRAM § 623.14 Easement...

  4. 7 CFR 987.35 - Modifications.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Marketing Policy § 987.35 Modifications. In the event the Committee subsequently determines that the marketing policy should be modified due to...

  5. Modifications to the Flexible Spacecraft Dynamics Program

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Modifications to existing subroutines are briefly described and a detailed description of new subroutines is given. The capability to simulate the Dynamics Explorer-B control system new developed and the formulation for this addition is given. The program variables in new labelled COMMON blocks are described in detail and the modified input and output for the d Flexible Spacecraft Dynamics Program is described.

  6. Microscale surface modifications for heat transfer enhancement.

    PubMed

    Bostanci, Huseyin; Singh, Virendra; Kizito, John P; Rini, Daniel P; Seal, Sudipta; Chow, Louis C

    2013-10-09

    In this experimental study, two surface modification techniques were investigated for their effect on heat transfer enhancement. One of the methods employed the particle (grit) blasting to create microscale indentations, while the other used plasma spray coating to create microscale protrusions on Al 6061 (aluminum alloy 6061) samples. The test surfaces were characterized using scanning electron microscopy (SEM) and confocal scanning laser microscopy. Because of the surface modifications, the actual surface area was increased up to 2.8× compared to the projected base area, and the arithmetic mean roughness value (Ra) was determined to vary from 0.3 μm for the reference smooth surface to 19.5 μm for the modified surfaces. Selected samples with modified surfaces along with the reference smooth surface were then evaluated for their heat transfer performance in spray cooling tests. The cooling system had vapor-atomizing nozzles and used anhydrous ammonia as the coolant in order to achieve heat fluxes up to 500 W/cm(2) representing a thermal management setting for high power systems. Experimental results showed that the microscale surface modifications enhanced heat transfer coefficients up to 76% at 500 W/cm(2) compared to the smooth surface and demonstrated the benefits of these practical surface modification techniques to enhance two-phase heat transfer process.

  7. 75 FR 31736 - Modifications of Debt Instruments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-04

    ... changes the instrument to an instrument or property right that is not debt for Federal income tax purposes... or property right that is not debt for Federal income tax purposes is a significant modification. For... some other property right for Federal income tax purposes. However, any portion of the increased...

  8. 7 CFR 1410.33 - Contract modifications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Contract modifications. 1410.33 Section 1410.33 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS CONSERVATION RESERVE PROGRAM § 1410.33...

  9. 7 CFR 1410.33 - Contract modifications.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Contract modifications. 1410.33 Section 1410.33 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS CONSERVATION RESERVE PROGRAM § 1410.33...

  10. 7 CFR 1410.33 - Contract modifications.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Contract modifications. 1410.33 Section 1410.33 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS CONSERVATION RESERVE PROGRAM § 1410.33...

  11. A Classroom Modification of the Ames Test.

    ERIC Educational Resources Information Center

    Yavornitzky, Joseph; Trzeciak, Victor

    1979-01-01

    A modification of the Ames test for detecting carcinogens and mutagens using a strain of bacteria is described. A suggestion is given for checking the correctness of procedures by using particular hair dyes which have been shown to be mutogenic. (Author/SA)

  12. Genetic modifications for personal enhancement: a defence.

    PubMed

    Murphy, Timothy F

    2014-04-01

    Bioconservative commentators argue that parents should not take steps to modify the genetics of their children even in the name of enhancement because of the damage they predict for values, identities and relationships. Some commentators have even said that adults should not modify themselves through genetic interventions. One commentator worries that genetic modifications chosen by adults for themselves will undermine moral agency, lead to less valuable experiences and fracture people's sense of self. These worries are not justified, however, since the effects of modification will not undo moral agency as such. Adults can still have valuable experiences, even if some prior choices no longer seem meaningful. Changes at the genetic level will not always, either, alienate people from their own sense of self. On the contrary, genetic modifications can help amplify choice, enrich lives and consolidate identities. Ultimately, there is no moral requirement that people value their contingent genetic endowment to the exclusion of changes important to them in their future genetic identities. Through weighing risks and benefits, adults also have the power to consent to, and assume the risks of, genetic modifications for themselves in a way not possible in prenatal genetic interventions.

  13. Behavior Modification Techniques. I: Overcorrection. II: Punishment.

    ERIC Educational Resources Information Center

    Sovner, Robert, Ed.; Hurley, Anne Des Noyers, Ed.

    1983-01-01

    Two newsletters review the principles and application of two behavior modification techniques with mentally retarded persons: overcorrection and punishment. Overcorrection may be either restitutional, in which the client is made to restore the environment to a far better state than before the inappropriate behavior occurred, or positive practice…

  14. Cognitive Modification in the Small College.

    ERIC Educational Resources Information Center

    Greenstreet, Robert; Hoover, Debra L.

    Aided by her advisor, a communication apprehensive college senior majoring in speech communication at a small rural college developed a project designed to help herself and other apprehensives through cognitive modification. Six students enrolled in a speech communication course who were classified as communication apprehensive by the Personal…

  15. 40 CFR 60.397 - Modifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Modifications. 60.397 Section 60.397 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile and Light Duty Truck...

  16. 40 CFR 60.397 - Modifications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Modifications. 60.397 Section 60.397 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile and Light Duty Truck...

  17. 40 CFR 60.397 - Modifications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Modifications. 60.397 Section 60.397 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile and Light Duty Truck...

  18. Protein modification during antiviral heat bioprocessing.

    PubMed

    Smales, C M; Pepper, D S; James, D C

    2000-01-20

    Heat treatment is routinely used in the preparation of therapeutic protein biopharmaceuticals as a means of viral inactivation. However, in undertaking virucidal heat treatments, a balance must be found between the bioprocessing conditions, virus kill, and the maintenance of protein integrity. In this study, we utilize a simple model protein, hen egg-white lysozyme, to investigate the relationship between antiviral bioprocess conditions (protein formulation and temperature) and the extent and type of protein modification. A variety of industrially relevant wet- and dry-heat treatments were undertaken, using formulations that included sucrose as a thermostabilizing excipient. Although there was no evidence of lysozyme aggregation or crosslinking during any of the heat treatments, using liquid chromatography-electrospray ionization-mass spectroscopy (LC-ESI-MS) and peptide mapping we show that protein modifications do occur with increasingly harsh heat treatment. Modifications were predominantly found after wet-heat treatment, the major covalent modification of lysozyme under these conditions being glycation of Lys(97), by either glucose or fructose derived from hydrolyzed sucrose. The extent of sucrose hydrolysis was itself dependent on both the duration of heat treatment and formulation composition. Advanced glycation end products (AGEs) and additional unidentified products were also present in protein samples subjected to extended heat treatment. AGEs were derived primarily from initial glycation by fructose and not glucose. These findings have implications for the improvement of bioprocesses to ensure protein product quality.

  19. 14 CFR 420.47 - License modification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION LICENSING LICENSE TO OPERATE A LAUNCH SITE License Terms and Conditions § 420.47 License... operate a launch site has been issued, a licensee shall apply to the FAA for modification of its license if: (1) The licensee proposes to operate the launch site in a manner that is not authorized by...

  20. [Modification in subtotal laryngectomy with epiglottoplasty].

    PubMed

    Rosique Arias, M; Hellín Meseguer, D; Albaladejo Devis, I

    2001-05-01

    We describe the modification in one of the passages of the technique of subtotal laryngectomy with epiglottoplasty, consisting of the opening of larynx through the thyroid membrane. This maneuver improves the visualization of the tumor facilitating the time of its removal and later reconstruction.

  1. Determinants of Treatment Modification in Hypercholesterolemic Patients

    PubMed Central

    Wang, Ko-Fan; Wu, Cheng-Hsueh; Chang, Chun-Chin; Chen, Lung-Ching; Wang, Kang-Ling; Lu, Tse-Min; Lin, Shing-Jong; Chiang, Chern-En

    2017-01-01

    Background There is a lack of knowledge of those contemporary factors associated with modifying subtherapeutic treatments in hypercholesterolemic patients. The aim of this study was to assess determinants of treatment modification in patients not attaining their low-density lipoprotein cholesterol goals. Methods The centralized Pan-Asian survey on the under-treatment of hypercholesterolemia enrolled patients taking stable lipid-lowering medications. The study physicians then determined existing patient treatments, which were to be continued or modified when treatments failed. The patient questionnaire surveying patient attitudes and perceptions toward their hypercholesterolemia management was prospectively collected. The odds ratios (ORs) (95% confidence intervals) were calculated. Results Among the 420 patients included for analysis, 35.7% were designated for planned treatment modification. Those patients assigned to treatment modification were more likely to have a family history of premature coronary heart disease (40% vs. 19%), an indication for secondary prevention (76% vs. 61%), elevated triglyceride (60% vs. 48%) and fasting sugar (84% vs. 67%), and were less adherent to their medications (29% vs. 12%) than patients assigned to treatment continuation. Patient recognition of treatment failure [OR, 1.82 (1.13-2.94)], the lower frequency of cholesterol checkup [OR, 2.40 (1.41-4.08)], patient satisfaction with provided cholesterol information [OR, 2.30 (1.21-4.39)], and their feelings toward cholesterol management [OR, 0.25 (0.10-0.62) and 3.80 (2.28-6.32)] for confusion and no strong feeling, respectively were determinants of the treatment modification assignment. Conclusions There was a large gap between evidence-based goals and modification of subtherapeutic treatments, particularly among patients with lower treatment satisfaction and better compliance. Our findings have emphasized the need to further reduce inertia in implementing hypercholesterolemia

  2. EDITORIAL: Novel applications of surface modification

    NASA Astrophysics Data System (ADS)

    Truman, C. E.

    2008-09-01

    This cluster issue of Journal of Physics D: Applied Physics arises from the Novel Applications of Surface Modification Conference (NASM 2007) held at Southampton University during 18-20 September 2007. It contains a collection of six papers based on both invited and contributed presentations at the conference. The NASM 2007 conference was organized by the Applied Physics and Technology Division of the Institute of Physics, and was co-sponsored by the Institute of Materials, Minerals and Mining, the Institution of Mechanical Engineers and the British Vacuum Council. The modification of the surface of a material allows the production of far superior products in terms of reduced wear, increased corrosion resistance, better biocompatibility, improved optical properties and altered electrical/electronic properties. Clearly, as surface modification methods improve, there are many more possible applications of such surface tailoring methods. The NASM 2007 Conference was planned so that scientists, engineers and manufacturers in different fields could come together to appraise the present applications of surface modification, establish where opportunities lie, identify the most significant challenges and address how problems should be tackled. The six papers contained within the cluster illustrate the diversity and breadth of the conference. The papers describe state-of-the-art research on a wide cross-section of topics, all unified by the overall theme of novel applications of surface modification. Specifically, papers are presented which consider nanoimprint lithography, statistical distributions of the coefficient of friction, the sliding drop method for optimizing surface energies for patterning in a roll-to-roll process, shakedown of residual stresses in titanium alloys, functionalized polymers and the determination of the electrochemically active surface area of Pt/C PEM fuel cell electrodes. The papers are authored by both academics and industrialists, further

  3. 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…

  4. 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

  5. [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.

  6. 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

  7. Caractérisation de l'état de surface et des contraintes résiduelles engendrées par meulage

    NASA Astrophysics Data System (ADS)

    Gognau, D.; Blehaut, H.; Dürr, J.; Hariri, S.; Khouchaf, L.; Flahaut, P.

    2002-07-01

    grinding operations are generally used to prepare surfaces or improve surface state before or after welding. These operations, when carried out manually with portable machines, induce superficial work hardening, modification of the structure of material and residual stresses. An experimental study about the influence of grinding has been carried out on two metallic materials, a low carbon steel (A42-CP) and an austenitic stainless steel (316L), in order to characterise the grinding effects. Manual grinding being difficult to control (no repeatable effects), a test rig using a portable machine has been made. This test rig enables to control the grinding parameters in order to obtain repeatable grinding operations. Characterisation of the ground surfaces was made by 2D profilometry and measurements of residual stresses have been carried out with a Set-X Elphyse apparatus. The profiles of residual stresses obtained show, on the one hand, that on each material, identical grindings generate identical states of stresses and on the other hand, that materials have not the same behaviour, From a metallurgical point of view, we also observe that the grinding effects are different for both materials. The grinding of the A42 steel highlights a crushing of the grain near the surface while the 316L stainless steel grinding reveals sliding bands. Des opérations de meulage sont régulièrement effectuées sur des matériaux métalliques pour préparer les surfaces ou pour améliorer l'état de ces surfaces après soudage. Ces opérations réalisées manuellement engendrent un écrouissage superficiel, une modification de la structure du matériau et par conséquent des contraintes résiduelles. Une étude expérimentale a été menée sur un acier à bas carbone (A42-CP) et un acier inoxydable austénitique (316L) afin de caractériser les effets du meulage. Le meulage manuel étant difficile à maîtriser (effets non reproductibles), un banc d'essai utilisant une machine

  8. Nuclear modifications of Parton Distribution Functions

    NASA Astrophysics Data System (ADS)

    Adeluyi, Adeola Adeleke

    This dissertation addresses a central question of modern nuclear physics: how does the behavior of fundamental degrees of freedom (quarks and gluons) change in the nuclear environment? This is an important aspect of experimental studies at current facilities such as the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory and the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Laboratory (JLAB). It is also highly relevant to planned experimental efforts at the Large Hadron Collider (LHC) and the future Electron Ion Collider (EIC). All these facilities probe matter via collisions involving nuclei; thus complications arise due to the presence of the attendant nuclear medium. Theoretical efforts to understand and interpret experimental results from such collisions are therefore largely dependent on the resolution of this question. The development of nuclear physics demonstrates that theoretical description is most efficient in terms of the effective degrees of freedom relevant to the scale (energy) being probed. Thus at low energies, nuclei are described as bound states of protons and neutrons (nucleons). At higher energies, the nucleons are no longer elementary, but are revealed to possess an underlying substructure: they are made up of quarks and gluons, collectively termed partons. The mometum distributions of these partons in the nucleon are referred to as Parton Distribution Functions (PDFs). Parton distributions can be determined from experimental measurements of structure functions. The ratio of nuclear structure functions to nucleon structure functions (generically referred to as nuclear ratio) is a measure of the nuclear modifications of the free nucleon PDFs. Thus a study of the nuclear ratio suffices to gain an understanding of nuclear modifications. In this dissertation we aim to describe theoretically nuclear modifications in a restricted region where the nuclear ratio is less than unity, the so

  9. 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

  10. Effect of site-specific modification on restriction endonucleases and DNA modification methyltransferases.

    PubMed Central

    McClelland, M; Nelson, M; Raschke, E

    1994-01-01

    Restriction endonucleases have site-specific interactions with DNA that can often be inhibited by site-specific DNA methylation and other site-specific DNA modifications. However, such inhibition cannot generally be predicted. The empirically acquired data on these effects are tabulated for over 320 restriction endonucleases. In addition, a table of known site-specific DNA modification methyltransferases and their specificities is presented along with EMBL database accession numbers for cloned genes. PMID:7937074

  11. 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.

  12. Analyse des facteurs prédictifs de malignité des goitres nodulaires : à propos de 500 cas

    PubMed Central

    Bouaity, Brahim; Darouassi, Youssef; Chihani, Mehdi; Touati, Mohamed Mliha; Ammar, Haddou

    2016-01-01

    Les nodules thyroïdiens sont très fréquents et moins de 10% d'entre eux sont malin. Ils posent un véritable problème diagnostique et thérapeutique surtout par rapport à leur nature bénigne ou maligne. L’étude de certains facteurs cliniques et paracliniques de présomption de malignité permet de bien codifier la stratégie thérapeutique. Le but de ce travail est d’étudier les facteurs prédictifs de malignité des goitres nodulaires et comparer nos résultats à ceux de la littérature. Il s'agit d'une étude rétrospective à propos de 500 cas de goitres nodulaires opérés au service d'Oto-rhino-laryngologie (ORL) et Chirurgie cervico-faciale (CCF) de l'hôpital militaire Avicenne de Marrakech entre 2006 et 2012. Le pourcentage de cancers a été de 6,8%. L’âge moyen de nos patients était de 46 ans, avec une sex-ratio de 5 (F/H). A la palpation cervicale; le caractère dure du nodule a été constaté dans 94,4% des cas de cancer, avec des limites irrégulières dans 64,70% des cas de cancer. Trois nodules étaient fixes et ils étaient tous malins. Les adénopathies cervicales ont été constatées chez 8 malades dont 7 présentaient des cancers. A l’échographie, 61,8% des nodules malins présentaient un aspect hypoéchogène, avec des contours flous dans 88,24% des cas. La vascularisation intra nodulaire était présente dans 35,3% de ces cas des cancers avec des microcalcifications chez 55,9% d'entre eux. Le halo hypoéchogene périnodulaire était incomplet dans 73,5% des cas de cancer. Nos patients étaient en euthyroïdie dans 84,6% des cas. Les facteurs prédictifs de malignité d'un goitre nodulaire, étaient donc dans notre étude d'abord cliniques: l’âge supérieur à 60 ans, la consistance dure du nodule, sa fixité, son caractère irrégulier et mal limité à la palpation, ainsi que la présence d'adénopathie(s) cervicale(s) à l'examen; et échographiques: le caractère hypoéchogène, les limites floues, la présence de

  13. Apport des neutrons à l'analyse structurale des composés partiellement désordonnés

    NASA Astrophysics Data System (ADS)

    Cousson, A.

    2003-02-01

    La cristallographie est un outil extrêmement puissant qui pourrait être utilisé par de nombreux scientifiques dont les sujets de recherche sont en fait très éloignés. L'évolution des techniques ces dernières années a relégué par exemple la cristallographie des rayons X des petites molécules à un rôle mineur, un rôle de service. Certains ont même le sentiment semble-t-il que toutes les connaissances sont contenues dans de multiples logiciels capables par eux-mêmes de conduire une analyse structurale à un résultat correct unique. Il est souhaitable que chacun soit capable de réaliser l'étude structurale du composé qui l'intéresse et bien entendu nécessaire de comprendre ce que l'on fait, la qualité des résultats et leur analyse en dépend. L'objet de cette présentation est de montrer l'apport spécifique de la diffraction de neutrons sur monocristaux à l'étude du désordre, en particulier des atomes d'hydrogène, et ses conséquences sur la compréhension des propriétés physiques, à partir de développements et d'exemples récents.

  14. Classification of DES16C2nm as a SLSN at z=1.998

    NASA Astrophysics Data System (ADS)

    Galbany, L.; D'Andrea, C.; Prajs, S.; Smith, M.; Sullivan, M.; Ponder, K.; Gonzalez-Gaitan, S.; Forster, F.; Hamuy, M.; Prieto, Jose Luis; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Macaulay, E.; Nichol, R.; Childress, 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.

    2016-11-01

    We report the spectroscopic classification of DES16C2nm as a superluminous supernova (SLSN) discovered by the Dark Energy Survey (ATEL #4668). DES16C2nm was discovered in the first epoch of DES Y4, on 22 August 2016 at R.A. = 03:40:14.83, Decl = -29:05:53.5 with i = 23.2 mag. DES16C2nm has a non-detection in the final epoch of DES Y3 on 08 February 2016.

  15. Formation des etoiles massives dans les galaxies spirales

    NASA Astrophysics Data System (ADS)

    Lelievre, Mario

    Le but de cette thèse est de décrire la formation des étoiles massives dans les galaxies spirales appartenant à divers types morphologiques. L'imagerie Hα profonde combinée à une robuste méthode d'identification des régions HII ont permis de détecter et de mesurer les propriétés (position, taille, luminosité, taux de formation d'étoiles) de plusieurs régions HII situées dans le disque interne (R < R25) de dix galaxies mais aussi à leur périphérie (R ≥ R 25). De façon générale, la répartition des régions HII ne montre aucune évidence de structure morphologique à R < R25 (bras spiraux, anneau, barre) à moins de limiter l'analyse aux régions HII les plus grosses ou les plus lumineuses. La répartition des régions HII, de même que leur taille et leur luminosité, sont toutefois sujettes à de forts effets de sélection qui dépendent de la distance des galaxies et qu'il faut corriger en ramenant l'échantillon à une résolution spatiale commune. Les fonctions de luminosité montrent que les régions HII les plus brillantes ont tendance à se former dans la portion interne du disque. De plus, l'analyse des pentes révèle une forte corrélation linéaire par rapport au type morphologique. Aucun pic n'est observé dans les fonctions de luminosité à log L-37 qui révèlerait la transition entre les régions HII bornées par l'ionisation et par la densité. Une relation cubique est obtenue entre la taille et la luminosité des régions HII, cette relation variant toutefois de façon significative entre le disque interne et la périphérie d'une même galaxie. La densité et la dynamique du gaz et des étoiles pourraient influencer de façon significative la stabilité des nuages moléculaires face à l'effondrement gravitationnel. D'une part, l'étendue du disque de régions HII pour cinq galaxies de l'échantillon coïncide avec celle de l'hydrogène atomique. D'autre part, en analysant la stabilité des disques galactiques, on conclue

  16. Symetries et integrabilite des equations aux differences finies

    NASA Astrophysics Data System (ADS)

    Lafortune, Stephane

    2000-09-01

    La présente thèse porte sur l'étude des symétries et des propriétés d'intégrabilité des équations aux différences finies. Dans le chapitre 1, le groupe de symétrie ponctuelle d'un système couplé à deux équations différentielles aux différences est étudié. On montre que dans certains cas, la dimension du groupe peut être infinie. Les équations peuvent décrire l'interaction de deux longues chaînes moléculaires, chacune étant composée d'atomes d'un même type. Dans le chapitre 2, une classe de théories de champs avec interaction exponentielle est introduite. L'interaction dépend de deux matrices de ``couplage'' et est suffisamment générale pour inclure toutes les théories de champs de Toda existant dans la littérature. Les symétries de Lie ponctuelles sont obtenues pour les cas où l'on a un nombre fini, infini ou semi-infini de champs. Une attention spéciale est accordée à la présence de l'invariance conforme. Dans le chapitre 3, nous procédons à la classification et à l'étude d'équations linéarisables. Nous examinons tout d'abord l'équation de Gambier continue qui contient, comme réductions, toutes les équations de deuxième ordre intégrables par linéarisation. Nous introduisons par la suite la forme discrète de cette équation et obtenons les conditions d'intégrabilité à l'aide du confinement des singularités. Nous étudions aussi les différentes réductions du cas discret. De plus, nous obtenons des transformations de Schlesinger pour les équations de Gambier discrète et continue. Dans la dernière partie du chapitre, nous étudions une famille d'équations discrètes du deuxième ordre incluant des équations résolubles par linéarisation. Plusieurs cas intégrables sont obtenus. Dans le cas discret, l'étude de l'intégrabilité est faite à l'aide du confinement des singularités. Dans le chapitre 4, nous étudions un autre critère d'intégrabilité: l'entropie algébrique. Nous montrons que les r

  17. Transport de paires EPR dans des structures mesoscopiques

    NASA Astrophysics Data System (ADS)

    Dupont, Emilie

    Dans cette these, nous nous sommes particulierement interesses a la propagation de paires EPR1 delocalisees et localisees, et a l'influence d'un supraconducteur sur le transport de ces paires. Apres une introduction de cette etude, ainsi que du cadre scientifique qu'est l'informatique quantique dans lequel elle s'inscrit, nous allons dans le chapitre 1 faire un rappel sur le systeme constitue de deux points quantiques normaux entoures de deux fils supraconducteurs. Cela nous permettra d'introduire une methode de calcul qui sera reutilisee par la suite, et de trouver egalement le courant Josephson produit par ce systeme transforme en SQUID-dc par l'ajout d'une jonction auxiliaire. Le SQUID permet de mesurer l'etat de spin (singulet ou triplet), et peut etre forme a partir d'autres systemes que nous etudierons ensuite. Dans le chapitre 2, nous rappellerons l'etude detaillee d'un intricateur d'Andreev faite par un groupe de Bale. La matrice T, permettant d'obtenir le courant dans les cas ou les electrons sont separes spatialement ou non, sera etudiee en detail afin d'en faire usage au chapitre suivant. Le chapitre 3 est consacre a l'etude de l'influence du bruit sur le fonctionnement de l'intricateur d'Andreev. Ce bruit modifie la forme du courant jusqu'a aboutir a d'autres conditions de fonctionnement de l'intricateur. En effet, le bruit present sur les points quantiques peut perturber le transport des paires EPR par l'intermediaire des degres de liberte. Nous montrerons que, du fait de l'"intrication" entre la charge de la paire et le bruit, la paire est detruite pour des temps longs. Cependant, le resultat le plus important sera que le bruit perturbe plus le transport des paires delocalisees, qui implique une resonance de Breit-Wigner a deux particules. Le transport parasite n'implique pour sa part qu'une resonance de Breit-Wigner a une particule. Dans le chapitre 4, nous reviendrons au systeme constitue de deux points quantiques entoures de deux fils

  18. D-region modification experiments at HAARP

    NASA Astrophysics Data System (ADS)

    Moore, R. C.; Agrawal, D.; Fujimaru, S.; Langston, J.

    2011-12-01

    This paper presents a summary of D-region modification experiments performed at the High-frequency Active Auroral Research Program (HAARP) observatory in 2011. Observations are used to compare the relative efficiencies various low-ELF wave generation mechanisms and to identify a new path toward improving the efficiency of ELF/VLF wave generation. Dual-beam HF heating experiments are used to assess the electrical properties of the lower ionosphere. HF cross-modulation experiments are used to identify the dominant altitude at which HF absorption occurs and to quantify the level of absorption as a function of HF power. In this paper, we compare experimental observations with the predictions of an ionospheric HF heating model and provide several recommendations to guide future D-region modification experiments.

  19. Posttranslational Modification Assays on Functional Protein Microarrays.

    PubMed

    Neiswinger, Johnathan; Uzoma, Ijeoma; Cox, Eric; Rho, HeeSool; Jeong, Jun Seop; Zhu, Heng

    2016-10-03

    Protein microarray technology provides a straightforward yet powerful strategy for identifying substrates of posttranslational modifications (PTMs) and studying the specificity of the enzymes that catalyze these reactions. Protein microarray assays can be designed for individual enzymes or a mixture to establish connections between enzymes and substrates. Assays for four well-known PTMs-phosphorylation, acetylation, ubiquitylation, and SUMOylation-have been developed and are described here for use on functional protein microarrays. Phosphorylation and acetylation require a single enzyme and are easily adapted for use on an array. The ubiquitylation and SUMOylation cascades are very similar, and the combination of the E1, E2, and E3 enzymes plus ubiquitin or SUMO protein and ATP is sufficient for in vitro modification of many substrates.

  20. Adaptive Control with Reference Model Modification

    NASA Technical Reports Server (NTRS)

    Stepanyan, Vahram; Krishnakumar, Kalmanje

    2012-01-01

    This paper presents a modification of the conventional model reference adaptive control (MRAC) architecture in order to improve transient performance of the input and output signals of uncertain systems. A simple modification of the reference model is proposed by feeding back the tracking error signal. It is shown that the proposed approach guarantees tracking of the given reference command and the reference control signal (one that would be designed if the system were known) not only asymptotically but also in transient. Moreover, it prevents generation of high frequency oscillations, which are unavoidable in conventional MRAC systems for large adaptation rates. The provided design guideline makes it possible to track a reference commands of any magnitude from any initial position without re-tuning. The benefits of the method are demonstrated with a simulation example

  1. Restriction/modification polypeptides, polynucleotides, and methods

    DOEpatents

    Westpheling, Janet; Chung, DaeHwan; Huddleston, Jennifer; Farkas, Joel A

    2015-02-24

    The present invention relates to the discovery of a novel restriction/modification system in Caldicellulosiruptor bescii. The discovered restriction enzyme is a HaeIII-like restriction enzyme that possesses a thermophilic activity profile. The restriction/modification system also includes a methyltransferase, M.CbeI, that methylates at least one cytosine residue in the CbeI recognition sequence to m.sup.4C. Thus, the invention provides, in various aspects, isolated CbeI or M.CbeI polypeptides, or biologically active fragments thereof; isolated polynucleotides that encode the CbeI or M.CbeI polypeptides or biologically active fragments thereof, including expression vectors that include such polynucleotide sequences; methods of digesting DNA using a CbeI polypeptide; methods of treating a DNA molecule using a M.CbeI polypeptide; and methods of transforming a Caldicellulosiruptor cell.

  2. Tissue modification with feedback: the smart scalpel

    NASA Astrophysics Data System (ADS)

    Sebern, Elizabeth L.; Brenan, Colin J. H.; Anderson, R. Rox; Hunter, Ian W.

    1998-10-01

    While feedback control is widespread throughout many engineering fields, there are almost no examples of surgical instruments that utilize a real-time detection and intervention strategy. This concept of closed loop feedback can be applied to the development of autonomous or semi- autonomous minimally invasive robotic surgical systems for efficient excision or modification of diseased tissue. Spatially localized regions of the tissue are first probed to distinguish pathological from healthy tissue based on differences in histochemical and morphological properties. Energy is directed to only the diseased tissue, minimizing collateral damage by leaving the adjacent healthy tissue intact. Continuous monitoring determines treatment effectiveness and, if needed, enables real-time treatment modifications to produce optimal therapeutic outcomes. The present embodiment of this general concept is a microsurgical instrument we call the Smart Scalpel, designed to treat skin angiodysplasias such as port wine stains. Other potential Smart Scalpel applications include psoriasis treatment and early skin cancer detection and intervention.

  3. Chitosan Modification and Pharmaceutical/Biomedical Applications

    PubMed Central

    Zhang, Jiali; Xia, Wenshui; Liu, Ping; Cheng, Qinyuan; Tahirou, Talba; Gu, Wenxiu; Li, Bo

    2010-01-01

    Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Our recent efforts focused on the chemical and biological modification of chitosan in order to increase its solubility in aqueous solutions and absorbability in the in vivo system, thus for a better use of chitosan. This review summarizes chitosan modification and its pharmaceutical/biomedical applications based on our achievements as well as the domestic and overseas developments: (1) enzymatic preparation of low molecular weight chitosans/chitooligosaccharides with their hypocholesterolemic and immuno-modulating effects; (2) the effects of chitin, chitosan and their derivatives on blood hemostasis; and (3) synthesis of a non-toxic ion ligand—D-Glucosaminic acid from Oxidation of D-Glucosamine for cancer and diabetes therapy. PMID:20714418

  4. Knowledge acquisition through anticipation of modifications

    SciTech Connect

    Lefkowitz, L.S.

    1987-01-01

    Knowledge bases for expert systems are typically constructed and refined using information obtained through a series of dialogs between an expert in the application domain and a knowledge engineer. The assimilation of this information into an existing knowledge base is an important aspect of the knowledge engineer's task. This assimilation process requires an understanding of how the new information corresponds to that already contained in the knowledge base and how the existing information must be modified so as to reflect the expert's view of the domain. This work describes a new approach to knowledge acquisition and presents a system that implements this approach. This system modifies an existing knowledge base using information obtained during a discourse with a domain expert. Heuristic knowledge about the knowledge-acquisition process enables the system to anticipate modifications to existing entity descriptions. These anticipated modifications, or expectations, are used to provide a context in which to assimilate the new domain information.

  5. Surface modification of magnetic nanoparticles in biomedicine

    NASA Astrophysics Data System (ADS)

    Chu, Xin; Yu, Jing; Hou, Yang-Long

    2015-01-01

    Progress in surface modification of magnetic nanoparticles (MNPs) is summarized with regard to organic molecules, macromolecules and inorganic materials. Many researchers are now devoted to synthesizing new types of multi-functional MNPs, which show great application potential in both diagnosis and treatment of disease. By employing an ever-greater variety of surface modification techniques, MNPs can satisfy more and more of the demands of medical practice in areas like magnetic resonance imaging (MRI), fluorescent marking, cell targeting, and drug delivery. Project supported by the National Natural Science Foundation of China (Grant Nos. 51125001 and 51172005), the Natural Science Foundation of Beijing,China (Grant No. 2122022), the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No. 81421004), and the Doctoral Program of the Education Ministry of China (Grant No. 20120001110078).

  6. Diagonal chromatography to study plant protein modifications.

    PubMed

    Walton, Alan; Tsiatsiani, Liana; Jacques, Silke; Stes, Elisabeth; Messens, Joris; Van Breusegem, Frank; Goormachtig, Sofie; Gevaert, Kris

    2016-08-01

    An interesting asset of diagonal chromatography, which we have introduced for contemporary proteome research, is its high versatility concerning proteomic applications. Indeed, the peptide modification or sorting step that is required between consecutive peptide separations can easily be altered and thereby allows for the enrichment of specific, though different types of peptides. Here, we focus on the application of diagonal chromatography for the study of modifications of plant proteins. In particular, we show how diagonal chromatography allows for studying proteins processed by proteases, protein ubiquitination, and the oxidation of protein-bound methionines. We discuss the actual sorting steps needed for each of these applications and the obtained results. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.

  7. Effectiveness of decanter modifications on organic removal

    SciTech Connect

    Lambert, D.P.

    1992-08-20

    A series of runs were planned in the Precipitate Hydrolysis Experimental Facility (PHEF) at the Savannah River Plant to determine the effectiveness of equipment and process modifications on the PHEF decanter organic removal efficiency. Runs 54-59 were planned to test the effectiveness of spray recirculation, a new decanter, heated organic recirculation and aqueous drawoff on organic removal efficiency in the revised HAN flowsheet. Runs 60-63 were planned to provide a comparison of the original and new decanter designs on organic removal efficiency in the late wash flowsheet without organic recirculation. Operational problems were experienced in both the PHEF and IDMS pilot facilities because of the production of high boiling organics and the low organic removal efficiency of the PHEF decanters. To prevent these problems in the DWPF Salt and Chemical Cells, modifications were proposed to the decanter and flowsheet to maximize the organic removal efficiency and minimize production of high boiling organics.

  8. Nonenzymatic posttranslational protein modifications in ageing.

    PubMed

    Soskić, Vukić; Groebe, Karlfried; Schrattenholz, André

    2008-04-01

    One of the most fundamental molecular aspects of aging is accumulating oxidative damage caused by reactive oxygen species (ROS) as proposed by the free radical theory of aging. These unwanted chemical side products of normal metabolism lead to the formation of altered, less active and potentially toxic species of DNA, RNA, proteins, lipids, and small molecules. Due to gradually accumulating small contributions of irreversible reactions during ageing, uncatalyzed chemical side reactions occur with increasing frequencies and repair functions decline. Eventually key biochemical pathways are impaired by increasingly less efficient cellular stress management. In this review, we describe the chemical nature of nonenzymatic age-related modifications of proteins and provide an overview of related analytical challenges and approaches, with a focus on mass spectrometry. We include the description of a strategy to rapidly exploit the wealth of mass spectrometric information from standard MALDI-TOF peptide fingerprints for the characterisation of age-related oxidative amino acid modifications.

  9. Studies on purothionin by chemical modifications.

    PubMed

    Wada, K; Ozaki, Y; Matsubara, H; Yoshizumi, H

    1982-01-01

    Purothionin from wheat flour was chemically modified by acetic or succinic anhydride under specific conditions. The complete modification of all amino groups of purothionin caused a large change in the net charge of the molecule, leading to the loss of the toxicity to mice and yeast. The sole tyrosyl residue in purothionin was nitrated by tetranitromethane at neutral pH or iodinated by the lactoperoxidase method. The nitro- and diiodo-derivatives of purothionin showed considerably reduced toxicity. Based on these modification studies we conclude that the positive charges of lysyl residues have an important role in the interaction with the negatively charged cell surface, and that the emergence of the toxicity of purothionin depends on a certain state of the tyrosyl residue.

  10. Opération multimode transverse des OPOs: des structures classiques aux corrélations quantiques

    NASA Astrophysics Data System (ADS)

    Martinelli, M.; Ducci, S.; Gigan, S.; Treps, N.; Maître, A.; Fabre, C.

    2002-06-01

    Nous démontrons la formation de structures transverses sur les faisceaux émis par un oscillateur paramétrique optique (OPO) de type II en configuration confocale. D'un point de vue classique nous mettons en évidence le caractère multimode transverse de telles structures. A travers l'étude des corrélations spatiales des faisceaux générés nous montrons que ces structures sont également multimodes d'un point de vue quantique.

  11. Apport des moyens endoscopiques dans la dilatation des sténoses caustiques de l’œsophage

    PubMed Central

    Seydou, Togo; Abdoulaye, Ouattara Moussa; xing, Li; Zi, Sanogo Zimogo; sekou, Koumaré; Wen, Yang Shang; Ibrahim, Sankare; Sekou, Toure Cheik Ahmed; Boubacar, Maiga Ibrahim; Saye, Jacque; Jerome, Dakouo Dodino; Dantoumé, Toure Ousmane; Sadio, Yena

    2016-01-01

    Introduction Toutes les sténoses symptomatiques de l’œsophage peuvent être dilatées par voie endoscopique. Nous évaluons l'apport des moyens endoscopiques dans la prise en charge de la dilatation œsophagienne pour sténose caustique de l’œsophage (SCO) au Mali. Méthodes IL s'agissait d'une étude descriptive et prospective réalisée dans le service de chirurgie thoracique à l'hôpital du Mali. Au total 46 dossiers cliniques de patients on été enregistrés et subdivisés en 4 groupes en fonction de la topographie des lésions cicatricielles. Le nombre de cas d'assistance endoscopique réalisé a été déterminé afin de comprendre l'apport des moyens endoscopiques dans le succès de la dilatation des SCO. Pour les 2 différentes méthodes de dilatation utilisées, le résultat du traitement et le coût ont comparés. Résultats La FOGD a été utilisée dans 19 cas (41.30%) de dilatation avec la bougie de Savary Guillard et dans 47.82% des cas dans la dilatation de Lerut. La vidéo-laryngoscopie a été utilisé 58.69% des cas de dilatation à la bougie de Lerut. Le passage de guide métallique et / ou de fil-guide a été réalisée dans 39.13% avec la vidéo laryngoscopie et dans 58.68% avec la FOGD. Dans la comparaison des deux méthodes, il existe une différence significative dans la survenue des complications (p=0.04075), l'anesthésie générale (p=0.02287), l'accessibilité à la méthode (p=0.04805) et la mortalité (p=0.00402). Conclusion La SCO est une pathologie grave et sous évaluée au Mali. Les moyens endoscopiques contribuent considérablement au succès de la dilatation œsophagienne pour sténose caustique dans les différentes méthodes utilisées. PMID:27200129

  12. Regioselective chemical modification of monoclonal antibodies

    DOEpatents

    Ranadive, Girish; Rosenzweig, Howard S.; Epperly, Michael; Bloomer, William

    1993-01-01

    A method of selectively modifying an immunoglobulin having at least one Fab region and at least one Fc region, each region having an isoelectric point wherein said isoelectric point of the Fab fragment of said immunoglobulin is different than the isoelectric point of the Fc fragment of the immunoglobulin, said method comprising modification of the immunoglobulin at a pH between the respective isoelectric points of the Fab and Fc fragments of the immunoglobulin.

  13. Food modification versus oral liquid nutrition supplementation.

    PubMed

    Silver, Heidi J

    2009-01-01

    Oral liquid nutrition supplements (ONS) are widely used in community, residential and healthcare settings. ONS are intended for individuals whose nutrient requirements cannot be achieved by conventional diet or food modification, or for the management of distinctive nutrient needs resulting from specific diseases and/or conditions. ONS appear to be most effective in patients with a body mass index of

  14. Regioselective chemical modification of monoclonal antibodies

    DOEpatents

    Ranadive, G.; Rozenzweig, H.S.; Epperly, M.; Bloomer, W.

    1993-05-04

    A method is presented of selectively modifying an immunoglobulin having at least one Fab region and at least one Fc region. Each region has an isoelectric point where the isoelectric point of the Fab fragment of the immunoglobulin is different from the isoelectric point of the Fc fragment of the immunoglobulin. The method comprises of a modification of the immunoglobulin at a pH between the respective isoelectric points of the Fab and Fc fragments of the immunoglobulin.

  15. Laser modification of thermally sprayed coatings

    NASA Astrophysics Data System (ADS)

    Uglov, A. A.; Fomin, A. D.; Naumkin, A. O.; Pekshev, P. Iu.; Smurov, I. Iu.

    1987-08-01

    Experimental results are reported on the modification of thermally sprayed coatings on steels and aluminum alloys using pulsed YAG and CW CO2 lasers. In particular, results obtained for self-fluxing Ni9CrBSi powders, ZRO2 ceramic, and titanium are examined. It is shown that the laser treatment of thermally sprayed coatings significantly improves their physicomechanical properties; it also makes it possible to obtain refractory coatings on low-melting substrates with good coating-substrate adhesion.

  16. Firmware Modification Analysis in Programmable Logic Controllers

    DTIC Science & Technology

    2014-03-27

    MODIFICATION ANALYSIS IN PROGRAMMABLE LOGIC CONTROLLERS Arturo M. Garcia Jr., B.S.S.E.C.A. Captain, USA Approved: //signed// Robert F. Mills , PhD...Matthew 5:37 v Acknowledgments My sincere gratitude to my committee for their guidance and teamwork which made this thesis possible. Dr. Mills ...2012. 2012. [5] Bolton, William. Programmable logic controllers. Newnes, 2009. [6] Boyer, Stuart . SCADA: Supervisory Control and Data Aquisition 4th

  17. Subtractive Structural Modification of Morpho Butterfly Wings.

    PubMed

    Shen, Qingchen; He, Jiaqing; Ni, Mengtian; Song, Chengyi; Zhou, Lingye; Hu, Hang; Zhang, Ruoxi; Luo, Zhen; Wang, Ge; Tao, Peng; Deng, Tao; Shang, Wen

    2015-11-11

    Different from studies of butterfly wings through additive modification, this work for the first time studies the property change of butterfly wings through subtractive modification using oxygen plasma etching. The controlled modification of butterfly wings through such subtractive process results in gradual change of the optical properties, and helps the further understanding of structural optimization through natural evolution. The brilliant color of Morpho butterfly wings is originated from the hierarchical nanostructure on the wing scales. Such nanoarchitecture has attracted a lot of research effort, including the study of its optical properties, its potential use in sensing and infrared imaging, and also the use of such structure as template for the fabrication of high-performance photocatalytic materials. The controlled subtractive processes provide a new path to modify such nanoarchitecture and its optical property. Distinct from previous studies on the optical property of the Morpho wing structure, this study provides additional experimental evidence for the origination of the optical property of the natural butterfly wing scales. The study also offers a facile approach to generate new 3D nanostructures using butterfly wings as the templates and may lead to simpler structure models for large-scale man-made structures than those offered by original butterfly wings.

  18. Integrated Microfluidics for Protein Modification Discovery.

    PubMed

    Noach-Hirsh, Meirav; Nevenzal, Hadas; Glick, Yair; Chorni, Evelin; Avrahami, Dorit; Barbiro-Michaely, Efrat; Gerber, Doron; Tzur, Amit

    2015-10-01

    Protein post-translational modifications mediate dynamic cellular processes with broad implications in human disease pathogenesis. There is a large demand for high-throughput technologies supporting post-translational modifications research, and both mass spectrometry and protein arrays have been successfully utilized for this purpose. Protein arrays override the major limitation of target protein abundance inherently associated with MS analysis. This technology, however, is typically restricted to pre-purified proteins spotted in a fixed composition on chips with limited life-time and functionality. In addition, the chips are expensive and designed for a single use, making complex experiments cost-prohibitive. Combining microfluidics with in situ protein expression from a cDNA microarray addressed these limitations. Based on this approach, we introduce a modular integrated microfluidic platform for multiple post-translational modifications analysis of freshly synthesized protein arrays (IMPA). The system's potency, specificity and flexibility are demonstrated for tyrosine phosphorylation and ubiquitination in quasicellular environments. Unlimited by design and protein composition, and relying on minute amounts of biological material and cost-effective technology, this unique approach is applicable for a broad range of basic, biomedical and biomarker research.

  19. Integrated Microfluidics for Protein Modification Discovery*

    PubMed Central

    Noach-Hirsh, Meirav; Nevenzal, Hadas; Glick, Yair; Chorni, Evelin; Avrahami, Dorit; Barbiro-Michaely, Efrat; Gerber, Doron; Tzur, Amit

    2015-01-01

    Protein post-translational modifications mediate dynamic cellular processes with broad implications in human disease pathogenesis. There is a large demand for high-throughput technologies supporting post-translational modifications research, and both mass spectrometry and protein arrays have been successfully utilized for this purpose. Protein arrays override the major limitation of target protein abundance inherently associated with MS analysis. This technology, however, is typically restricted to pre-purified proteins spotted in a fixed composition on chips with limited life-time and functionality. In addition, the chips are expensive and designed for a single use, making complex experiments cost-prohibitive. Combining microfluidics with in situ protein expression from a cDNA microarray addressed these limitations. Based on this approach, we introduce a modular integrated microfluidic platform for multiple post-translational modifications analysis of freshly synthesized protein arrays (IMPA). The system's potency, specificity and flexibility are demonstrated for tyrosine phosphorylation and ubiquitination in quasicellular environments. Unlimited by design and protein composition, and relying on minute amounts of biological material and cost-effective technology, this unique approach is applicable for a broad range of basic, biomedical and biomarker research. PMID:26276765

  20. Bivalent histone modifications in early embryogenesis.

    PubMed

    Vastenhouw, Nadine L; Schier, Alexander F

    2012-06-01

    Histone modifications influence the interactions of transcriptional regulators with chromatin. Studies in embryos and embryonic stem (ES) cells have uncovered histone modification patterns that are diagnostic for different cell types and developmental stages. For example, bivalent domains consisting of regions of H3 lysine 27 trimethylation (H3K27me3) and H3 lysine 4 trimethylation (H3K4me3) mark lineage control genes in ES cells and zebrafish blastomeres. Such bivalent domains have garnered attention because the H3K27me3 mark might help repress lineage-regulatory genes during pluripotency while the H3K4me3 mark could poise genes for activation upon differentiation. Despite the prominence of the bivalent domain concept, studies in other model organisms have questioned its universal nature, and the function of bivalent domains has remained unclear. Histone marks are also associated with developmental regulatory genes in sperm. These observations have raised the possibility that specific histone modification patterns might persist from parent to offspring, but it is unclear whether histone marks are inherited or formed de novo. Here, we review the potential roles of H3K4me3 and H3K27me3 marks in embryos and ES cells and discuss how histone marks might be established, maintained and resolved during embryonic development.

  1. Particle Distribution Modification by Low Amplitude Modes

    SciTech Connect

    White, R. B.; Gorelenkov, N.; Heidbrink, W. W.; Van Zeeland, M. A.

    2009-08-28

    Modification of a high energy particle distribution by a spectrum of low amplitude modes is investigated using a guiding center code. Only through resonance are modes effective in modifying the distribution. Diagnostics are used to illustrate the mode-particle interaction and to find which effects are relevant in producing significant resonance, including kinetic Poincare plots and plots showing those orbits with time averaged mode-particle energy transfer. Effects of pitch angle scattering and drag are studied, as well as plasma rotation and time dependence of the equilibrium and mode frequencies. A specific example of changes observed in a DIII-D deuterium beam distribution in the presence of low amplitude experimentally validated Toroidal Alfven (TAE) eigenmodes and Reversed Shear Alfven (RSAE) eigenmodes is examined in detail. Comparison with experimental data shows that multiple low amplitude modes can account for significant modification of high energy beam particle distributions. It is found that there is a stochastic threshold for beam profile modification, and that the experimental amplitudes are only slightly above this threshold.

  2. CPLM: a database of protein lysine modifications

    PubMed Central

    Liu, Zexian; Wang, Yongbo; Gao, Tianshun; Pan, Zhicheng; Cheng, Han; Yang, Qing; Cheng, Zhongyi; Guo, Anyuan; Ren, Jian; Xue, Yu

    2014-01-01

    We reported an integrated database of Compendium of Protein Lysine Modifications (CPLM; http://cplm.biocuckoo.org) for protein lysine modifications (PLMs), which occur at active ε-amino groups of specific lysine residues in proteins and are critical for orchestrating various biological processes. The CPLM database was updated from our previously developed database of Compendium of Protein Lysine Acetylation (CPLA), which contained 7151 lysine acetylation sites in 3311 proteins. Here, we manually collected experimentally identified substrates and sites for 12 types of PLMs, including acetylation, ubiquitination, sumoylation, methylation, butyrylation, crotonylation, glycation, malonylation, phosphoglycerylation, propionylation, succinylation and pupylation. In total, the CPLM database contained 203 972 modification events on 189 919 modified lysines in 45 748 proteins for 122 species. With the dataset, we totally identified 76 types of co-occurrences of various PLMs on the same lysine residues, and the most abundant PLM crosstalk is between acetylation and ubiquitination. Up to 53.5% of acetylation and 33.1% of ubiquitination events co-occur at 10 746 lysine sites. Thus, the various PLM crosstalks suggested that a considerable proportion of lysines were competitively and dynamically regulated in a complicated manner. Taken together, the CPLM database can serve as a useful resource for further research of PLMs. PMID:24214993

  3. Surface modification: advantages, techniques, and applications

    SciTech Connect

    Natesan, K.

    2000-03-01

    Adequate performance of materials at elevated temperatures is a potential problem in many systems within the chemical, petroleum, process, and power-generating industries. Degradation of materials occurs because of interaction between the structural material and the exposure environment. These interactions are generally undesired chemical reactions that can lead to accelerated wastage and alter the functional requirements and/or structural integrity of the materials. Therefore, material selection for high-temperature applications must be based not only on a material strength properties but also on resistance to the complex environments prevalent in the anticipated exposure environment. As plants become larger, the satisfactory performance and reliability of components play a greater role in plant availability and economics. However, system designers are becoming increasingly concerned with finding the least expensive material that will satisfactorily perform the design function for the desired service life. This present paper addresses the benefits of surface modification and identified several criteria for selection and application of modified surfaces in the power sector. A brief review is presented on potential methods for modification of surfaces, with the emphasis on coatings. In the final section of the paper, several examples address the requirements of different energy systems and surface modification avenues that have been applied to resolve the issues.

  4. Post-production modification of industrial enzymes.

    PubMed

    Minten, Inge J; Abello, Nicolas; Schooneveld-Bergmans, Margot E F; van den Berg, Marco A

    2014-01-01

    Industry has an increasing interest in the use of enzymes as environmentally friendly, highly efficient, and specific bio-catalysts. Enzymes have primarily evolved to function in aqueous environments at ambient temperature and pressure. These conditions however do not always correspond with industrial processes or applications, and only a small portion of all known enzymes are therefore suitable for industrial use. Protein engineering can sometimes be applied to convey more desirable properties to enzymes, such as increased stability, but is limited to the 20 naturally occurring amino acids or homologs thereof. Using post-production modification, which has the potential to combine desirable properties from the enzyme and the conjugated compounds, enzymes can be modified with both natural and synthetic molecules. This offers access to a myriad of possibilities for tuning the properties of enzymes. At this moment, however, the effects of post-production modification cannot yet be reliably predicted. The increasing number of applications will improve this so that the potential of this technology can be fully exploited. This review will focus on post-production modification of enzymes and its use and opportunities in industry.

  5. Inorganic Surface Modification of Nonwoven Polymeric Substrates

    NASA Astrophysics Data System (ADS)

    Halbur, Jonathan Chandler

    In this study, atomic layer deposition (ALD), a vapor phase inorganic thin film deposition technique, is used to modify the surface of a range of industrially relevant polymers to enhance surface properties or impart additional functionalities. Several unique demonstrations of polymer surface modification are presented including uniform nanomaterial photodeposition to the surface of nonowoven fabrics and the first application of photocatalytic thin film coated nonwovens for advanced filtration of heavy metals from solution. Recent advances in polymer synthesis and processing technologies have resulted in the production of novel polymer systems with unique chemistries and sub-micron scale dimensions. As a result, advanced fiber systems have received much attention for potential use in a wide range of industrially and medically important applications such as advanced and selective filtration, catalysis, flexible electronics, and tissue engineering. However, tailoring the surface properties of the polymer is still needed in order to realize the full range of advanced applications, which can be difficult given the high complexity and non-uniformity of nonwoven polymeric structures. Uniform and controllable inorganic surface modification of nonwovens allows the introduction or modification of many crucial polymer properties with a wide range of application methods.

  6. Reproductive cloning combined with genetic modification.

    PubMed

    Strong, C

    2005-11-01

    Although there is widespread opposition to reproductive cloning, some have argued that its use by infertile couples to have genetically related children would be ethically justifiable. Others have suggested that lesbian or gay couples might wish to use cloning to have genetically related children. Most of the main objections to human reproductive cloning are based on the child's lack of unique nuclear DNA. In the future, it may be possible safely to create children using cloning combined with genetic modifications, so that they have unique nuclear DNA. The genetic modifications could be aimed at giving such children genetic characteristics of both members of the couple concerned. Thus, cloning combined with genetic modification could be appealing to infertile, lesbian, or gay couples who seek genetically related children who have genetic characteristics of both members. In such scenarios, the various objections to human reproductive cloning that are based on the lack of genetic uniqueness would no longer be applicable. The author argues that it would be ethically justifiable for such couples to create children in this manner, assuming these techniques could be used safely.

  7. Physical modification of food starch functionalities.

    PubMed

    BeMiller, James N; Huber, Kerry C

    2015-01-01

    Because, in general, native starches do not have properties that make them ideally suited for applications in food products, most starch is modified by dervatization to improve its functionality before use in processed food formulations, and because food processors would prefer not to have to use the modified food starch label designation required when chemically modified starches are used, there is considerable interest in providing starches with desired functionalities that have not been chemically modified. One investigated approach is property modification via physical treatments, that is, modifications of starches imparted by physical treatments that do not result in any chemical modification of the starch. Physical treatments are divided into thermal and nonthermal treatments. Thermal treatments include those that produce pregelatinized and granular cold-water-swelling starches, heat-moisture treatments, annealing, microwave heating, so-called osmotic pressure treatment, and heating of dry starch. Nonthermal treatments include ultrahigh-pressure treatments, instantaneous controlled pressure drop, use of high-pressure homogenizers, dynamic pulsed pressure, pulsed electric field, and freezing and thawing.

  8. 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

    -decharge. Neanmoins, il est encore possible de la relancer en cyclage par la suite. Une baisse de la valeur de la resistance totale interfaciale et des frequences au sonnet semble indiquer une modification chimique et/ou structurale des films de passivations, pent-etre due a une transformation de ces films lors du cyclage ou a leur degradation. (Abstract shortened by UMI.)

  9. 50 CFR 218.240 - Modifications to Letters of Authorization.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA) Sonar § 218.240 Modifications to Letters of... sonar system from one ship to another, is not considered a substantial modification. (b) If...

  10. 50 CFR 218.240 - Modifications to Letters of Authorization.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA) Sonar § 218.240 Modifications to Letters of... sonar system from one ship to another, is not considered a substantial modification. (b) If...

  11. 50 CFR 216.190 - Modifications to Letters of Authorization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA sonar) Sonar § 216.190 Modifications to Letters of... sonar system from one ship to another, is not considered a substantial modification. (b) If the...

  12. 50 CFR 216.190 - Modifications to Letters of Authorization.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA sonar) Sonar § 216.190 Modifications to Letters of... sonar system from one ship to another, is not considered a substantial modification. (b) If the...

  13. 50 CFR 218.240 - Modifications to Letters of Authorization.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Array Sensor System Low Frequency Active (SURTASS LFA) Sonar § 218.240 Modifications to Letters of... sonar system from one ship to another, is not considered a substantial modification. (b) If...

  14. 14 CFR 60.23 - Modifications to FSTDs.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE § 60.23 Modifications to FSTDs. (a... modification for flight crewmember training or evaluation or for obtaining flight experience for the...

  15. Étude par diffraction des rayons X des vernis rouges des sigillées du sud de la Gaule. Les ateliers de la Graufesenque

    NASA Astrophysics Data System (ADS)

    Vendier, L.; Sciau, Ph.; Dooryhee, E.

    2002-07-01

    La Graufesenque (Millau, Aveyron) 1^rst and 2^nd, centuries AC Sigillata red slips have been studied by x-ray diffraction at ESRF and on a conventional diffractometer. Although x-ray diffraction is a non-destructive characterisation technique adapted to surface study, it has not been used so mutch for Sigillata slip characterisation. The poor quality of the slip surface can be an explanation. In this work we demonstrate that it is possible to get good quality diffraction diagrams on 20-120 AC Sigillata slips. The results confirm the productions homogeneity and the hypothesis about a non-local clay used for the slips. On a counterpart, the late (second half of 2^nd century AC) Sigillata study needs because of their crackled surface a high quality beam, which can only be accessible on a synchrotron installation. These productions seems to be more heterogeneous: some Sigillata present similar diffraction diagrams for the slip and ceramic body (same clay?), some others present results similar to the precedent production period ones. Les vernis rouges de poteries sigillées (I^er et II^e siècles) de la Graufesenque (Millau, Aveyron) ont été étudiés par diffraction des rayons X à la fois à l'ESRF et sur une installation classique de laboratoire. Bien que la diffraction des rayons X soit une technique adaptée à l'étude des surfaces, cette technique a jusqu'à présent assez peu servi dans l'examen de ces objets. Ceci peut en partie s'expliquer par le mauvais état de surface de certains vernis. Dans ce travail, nous montrons que moyennant quelques précautions, il est possible d'obtenir sur une installation classique de bons diffractogranunes des vernis des sigillées datés entre 20 et 120 ap. J.C. Les résultats confirment l'homogénéité de ces productions et l'hypothèse selon laquelle ces vernis n'ont pas été fabriqués à partir des argiles locales du jurassique environnant le site. Par contre, l'étude des sigillées tardives de la deuxième moitié du

  16. Die Gasultrazentrifuge als mediale Projektion des Kalten Krieges

    NASA Astrophysics Data System (ADS)

    Helmbold, Bernd

    Studien der letzten Dekaden nach der Wiedervereinigung von BRD und DDR erweitern die Perspektive der Wissenschaftsgeschichte vom Fokus des Big Science und der technisch-militärisch-industriellen Auseinandersetzung zwischen den zwei Blöcken zu einer globalen Transformation im Konflikt der Supermächte geprägt durch lokale und auch interne Ausformungen.

  17. Simulations of the OzDES AGN reverberation mapping project

    SciTech Connect

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.

  18. Mechanistic Enzymology of the Radical SAM Enzyme DesII.

    PubMed

    Ruszczycky, Mark W; Liu, Hung-Wen

    2015-04-01

    DesII is a member of the radical SAM family of enzymes that catalyzes radical-mediated transformations of TDP-4-amino-4,6-didexoy-D-glucose as well as other sugar nucleotide diphosphates. Like nearly all radical SAM enzymes, the reactions begin with the reductive homolysis of SAM to produce a 5'-deoxyadenosyl radical which is followed by regiospecific hydrogen atom abstraction from the substrate. What happens next, however, depends on the nature of the substrate radical so produced. In the case of the biosynthetically relevant substrate, a radical-mediated deamination ensues; however, when this amino group is replaced with a hydroxyl, one instead observes dehydrogenation. The factors that govern the fate of the initially generated substrate radical as well as the mechanistic details underlying these transformations have been a key focus of research into the chemistry of DesII. This review will discuss recent discoveries pertaining to the enzymology of DesII, how it may relate to understanding other radical-mediated lyases and dehydrogenases and the working hypotheses currently being investigated regarding the mechanism of DesII catalysis.

  19. Recognition of Langue des Signes Quebecoise in Eastern Canada

    ERIC Educational Resources Information Center

    Parisot, Anne-Marie; Rinfret, Julie

    2012-01-01

    This article presents a portrait of two community-level and legal efforts in Canada to obtain official recognition of ASL and LSQ (Langue des signes quebecoise), both of which are recognized as official languages by the Canadian Association of the Deaf (CAD). In order to situate this issue in the Canadian linguistic context, the authors first…

  20. Chemical and structural effects of base modifications in messenger RNA

    NASA Astrophysics Data System (ADS)

    Harcourt, Emily M.; Kietrys, Anna M.; Kool, Eric T.

    2017-01-01

    A growing number of nucleobase modifications in messenger RNA have been revealed through advances in detection and RNA sequencing. Although some of the biochemical pathways that involve modified bases have been identified, research into the world of RNA modification -- the epitranscriptome -- is still in an early phase. A variety of chemical tools are being used to characterize base modifications, and the structural effects of known base modifications on RNA pairing, thermodynamics and folding are being determined in relation to their putative biological roles.

  1. Reactive modification of polyesters and their blends

    NASA Astrophysics Data System (ADS)

    Wan, Chen

    2004-12-01

    As part of a broader research effort to investigate the chemical modification of polyesters by reactive processing a low molecular weight (MW) unsaturated polyester (UP) and a higher MW saturated polyester, polyethylene terephthalate (PET), alone or blended with polypropylene (PP) were melt processed in a batch mixer and continuous twin screw extruders. Modification was monitored by on-line rheology and the products were characterized primarily by off-line rheology, morphology and thermal analysis. Efforts were made to establish processing/property relationships and provide an insight of the accompanying structural changes. The overall response of the reactively modified systems was found to be strongly dependent on the component characteristics, blend composition, type and concentrations of reactive additives and processing conditions. The work concluded that UP can be effectively modified through reactive melt processing. Its melt viscosity and MW can be increased through chemical reactions between organic peroxides (POX) and chain unsaturation or between MgO and carboxyl/hydroxyl end groups. Reactive blending of PP/UP blends through peroxide modification gave finer and more uniform morphology than unreacted blends and at a given PP/UP weight ratio more thermoplastic elastomers-like rheological behavior. This is due to the continuously decreasing viscosity ratio of PP/UP towards unity by the competing reactions between POX and the blend components and formation of PP-UP copolymers which serve as in-situ compatibilizers to promote better interfacial adhesion. Kinetics of the competing reactions were analyzed through a developed model. In addition to POX concentration and mixing efficiency, rheology and morphology of UP/PP bends were significantly affected by the addition of inorganic and organic coagents. Addition of coagents such as a difunctional maleimide, MgO and/or an anhydride functionalized PP during reactive blending offers effective means for tailoring

  2. L'Infection Nosocomiale en Reanimation des Brules

    PubMed Central

    Siah, S.; Belefqih, R.; Elouennass, M.; Fouadi, F.E.; Ihrai, I.

    2009-01-01

    Summary L'infection nosocomiale bactérienne étant l'une des principales causes de morbidité et de mortalité chez le brûlé, nous avons réalisé une étude rétrospective portant sur 84 patients hospitalisés au sein du service de réanimation des brûlés de l'Hôpital Militaire d'Instruction Mohammed V de Rabat, sur une période de 3 ans, du premier janvier 2001 au 31 décembre 2003. Les critères d'infection nosocomiale étaient ceux du Center for Disease Control d'Atlanta de 1988. Les taux d'incidence ont été calculés. La population infectée a été comparée à celle non infectée. L'écologie bactérienne du service a été décrite comme aussi l'antibiotype. Il ressort de cette étude la survenue de 87 infections nosocomiales chez 27 patients. L'incidence cumulative était de 103 infections pour 1000 jours de traitement. Pour ce qui est des caractéristiques des infections bactériennes, les sites infectés étaient la peau (77%), le sang (13,8%), les voies urinaires (8%) et les poumons (1,1%). Les principaux germes étaient: Staphylococcus sp. (33,3%), Pseudomonas aeruginosa (23%), Enterococcus faecalis et Acinetobacter (8%). Les staphylocoques étaient méticillo-résistants dans 22,2% des cas. Le Pseudomonas et l'Acinetobacter étaient multirésistants (60%). Dans notre étude les facteurs prédictifs de survenue des infections nosocomiales que nous avons retenus après l'étude comparative des populations infectées et non infectées ont été l'âge, le body mass index, l'abbreviated burn severity index et le remplissage initial. En isolant ces paramètres, nous avons pu établir une équation à valeur prédictive de survenue d'infection nosocomiale chez le patient brûlé. PMID:21991158

  3. 40 CFR 72.82 - Fast-track modifications.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority,...

  4. 10 CFR 835.1002 - Facility design and modifications.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Facility design and modifications. 835.1002 Section 835.1002 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Design and Control § 835.1002 Facility design and modifications. During the design of new facilities or modification of...

  5. 10 CFR 835.1002 - Facility design and modifications.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Facility design and modifications. 835.1002 Section 835.1002 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Design and Control § 835.1002 Facility design and modifications. During the design of new facilities or modification of...

  6. 10 CFR 835.1002 - Facility design and modifications.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Facility design and modifications. 835.1002 Section 835.1002 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Design and Control § 835.1002 Facility design and modifications. During the design of new facilities or modification of...

  7. 10 CFR 835.1002 - Facility design and modifications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Facility design and modifications. 835.1002 Section 835.1002 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Design and Control § 835.1002 Facility design and modifications. During the design of new facilities or modification of...

  8. Ecological Effects of Weather Modification: A Problem Analysis.

    ERIC Educational Resources Information Center

    Cooper, Charles F.; Jolly, William C.

    This publication reviews the potential hazards to the environment of weather modification techniques as they eventually become capable of producing large scale weather pattern modifications. Such weather modifications could result in ecological changes which would generally require several years to be fully evident, including the alteration of…

  9. 14 CFR 21.9 - Replacement and modification articles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  10. 14 CFR 21.9 - Replacement and modification articles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  11. 14 CFR 21.9 - Replacement and modification articles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  12. 14 CFR 21.9 - Replacement and modification articles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  13. 14 CFR 21.9 - Replacement and modification articles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Replacement and modification articles. 21.9... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS General § 21.9 Replacement and modification articles. (a) If a person knows, or should know, that a replacement or modification article is reasonably likely to...

  14. 26 CFR 1.1001-3 - Modifications of debt instruments.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... modification. Example 4. Substitution of a new obligor occurring by operation of the terms of the debt..., even though it occurs by operation of the terms of the bond, is a modification. Example 5. Defeasance... rate occurs by operation of the terms of the instrument and is not a modification. Example 9....

  15. 42 CFR 53.156 - Fees for modification requests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... processing of requests for parity, and for major and minor modifications of the terms of documents evidencing... submitted with each type of modification. (1) As used in this section, a request for parity allows new debt... modification, and (3) $5,500 for a request for parity. (c) A submitter may withdraw its request...

  16. 42 CFR 53.156 - Fees for modification requests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... processing of requests for parity, and for major and minor modifications of the terms of documents evidencing... submitted with each type of modification. (1) As used in this section, a request for parity allows new debt... modification, and (3) $5,500 for a request for parity. (c) A submitter may withdraw its request...

  17. 42 CFR 53.156 - Fees for modification requests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... processing of requests for parity, and for major and minor modifications of the terms of documents evidencing... submitted with each type of modification. (1) As used in this section, a request for parity allows new debt... modification, and (3) $5,500 for a request for parity. (c) A submitter may withdraw its request...

  18. 42 CFR 53.156 - Fees for modification requests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... processing of requests for parity, and for major and minor modifications of the terms of documents evidencing... submitted with each type of modification. (1) As used in this section, a request for parity allows new debt... modification, and (3) $5,500 for a request for parity. (c) A submitter may withdraw its request...

  19. 42 CFR 53.156 - Fees for modification requests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... processing of requests for parity, and for major and minor modifications of the terms of documents evidencing... submitted with each type of modification. (1) As used in this section, a request for parity allows new debt... modification, and (3) $5,500 for a request for parity. (c) A submitter may withdraw its request...

  20. 40 CFR 72.82 - Fast-track modifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Fast-track modifications. 72.82... (CONTINUED) PERMITS REGULATION Permit Revisions § 72.82 Fast-track modifications. The following procedures shall apply to all fast-track modifications. (a) If the Administrator is the permitting authority,...

  1. 48 CFR 43.103 - Types of contract modifications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Types of contract modifications. 43.103 Section 43.103 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT CONTRACT MODIFICATIONS General 43.103 Types of contract modifications....

  2. 47 CFR 74.1251 - Technical and equipment modifications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Technical and equipment modifications. 74.1251... Translator Stations and FM Broadcast Booster Stations § 74.1251 Technical and equipment modifications. (a) No.... Upon the installation or modification of the transmitting equipment for which prior FCC authority...

  3. 10 CFR 835.1002 - Facility design and modifications.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Facility design and modifications. 835.1002 Section 835.1002 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Design and Control § 835.1002 Facility design and modifications. During the design of new facilities or modification of...

  4. La biogenèse des mélanosomes

    PubMed Central

    Delevoye, Cédric; Giordano, Francesca; van Niel, Guillaume; Raposo, Graça

    2012-01-01

    Les mélanocytes situés à la base de l’épiderme produisent des mélanosomes qui sont transférés aux kératinocytes pour assurer la pigmentation de l’épiderme et sa photoprotection contre les rayons ultraviolets. Les mélanosomes, organites apparentés aux lysosomes, sont le lieu de synthèse et de stockage d’un pigment, la mélanine. Leur formation dépend de protéines mélanosomales qui transitent par les voies de biosynthèse et d’endocytose et exploitent les mécanismes moléculaires du trafic intracellulaire. Les acteurs moléculaires impliqués dans le transport des protéines mélanosomales et la biogenèse des mélanosomes sont la cible de mutations dans des maladies génétiques accompagnées d’hypopigmentation comme l’albinisme et les maladies lysosomales. Les études menées sur les mélanocytes issus de souris modèles de ces maladies permettent de comprendre certaines des étapes-clés de la mélanogenèse ainsi que les dysfonctionnements associés à ces pathologies. De plus, décrypter la mélanogenèse facilite également la compréhension d’autres processus physiologiques, comme l’illustrent les similitudes inattendues avec l’amyloïdogenèse dans les maladies neurodégénératives. PMID:21382323

  5. Les reseaux de politique publique comme facteur d'influence du choix des instruments de politique energetique canadienne a des fins environnementales de 1993 a nos jours

    NASA Astrophysics Data System (ADS)

    Fathy El Dessouky, Naglaa

    Au cours de la derniere decennie, les modes de la gouvernance ont pris place dans un contexte totalement different de celui qu'ils avaient auparavant. Les gouvernements modernes se rendent compte qu'ils perdent de plus en plus leur capacite a elaborer et a gerer les changements d'une maniere autonome. Ainsi, les fonctions et les activites traditionnellement accomplies exclusivement par le gouvernement engagent de nos jours une gamme d'acteurs etatiques et non etatiques. A l'encontre du concept traditionnel de l'Etat controleur, la gouvernance contemporaine est ainsi devenue moins une question d'offre de service et davantage une gestion indirecte des reseaux de politique publique. Dans cette entreprise, les gouvernements contemporains, cherchant plus d'information, de soutien et de legitimite en matiere de formulation des decisions, ont besoin d'etablir des relations avec les divers groupes d'interet qui, a leur tour, voulaient plus de promotion et de protection en faveur de leurs interets a travers leur implication au processus de l'elaboration et de la mise en oeuvre des politiques publiques. Ainsi, l'approche des reseaux de politique publique represente aujourd'hui un courant considerable au sein du champ d'analyse des politiques publiques. Toutefois, les preoccupations des chercheurs pour cette approche, dans le domaine des politiques energetiques a des fins environnementales, semblent recentes, et les etudes realisees sont encore trop peu nombreuses. Au Canada, au debut des annees 1990, le gouvernement ainsi que plusieurs groupes d'interets, des differents secteurs energetique, industriel et environnemental, ont commence a intensifier leurs efforts pour s'attaquer au probleme du changement climatique d'origine energetique, genere surtout par le secteur de l'industrie. Au cours de la derniere decennie, la question touchant plutot le sujet du developpement energetique durable represente le plus important domaine des politiques publiques ayant surgi recemment dans

  6. Lignes directrices canadiennes sur l’utilisation sécuritaire et efficace des opioïdes pour la douleur chronique non cancéreuse

    PubMed Central

    Kahan, Meldon; Wilson, Lynn; Mailis-Gagnon, Angela; Srivastava, Anita

    2011-01-01

    Résumé Objectif Présenter aux médecins de famille un résumé clinique pratique sur la prescription d’opioïdes à des populations particulières en se fondant sur les recommandations faites dans les lignes directrices canadiennes sur l’utilisation sécuritaire et efficace des opioïdes pour la douleur chronique non cancéreuse. Qualité des données Pour produire les lignes directrices, les chercheurs ont effectué une synthèse critique de la littérature médicale en insistant plus précisément sur les études de l’efficacité et de la sécurité des opioïdes dans des populations particulières. Message principal Les médecins de famille peuvent atténuer les risques de surdose, de sédation, d’usage abusif et de dépendance grâce à des stratégies adaptées à l’âge et à l’état de santé des patients. Dans le cas de patients à risque de dépendance, on devrait réserver les opioïdes aux douleurs nociceptives ou neuropathiques bien définies qui n’ont pas répondu aux traitements de première intention. Il faut procéder lentement au titrage des opioïdes, avec des dispensations fréquentes et une étroite surveillance pour dépister tout signe d’usage abusif. Une dépendance aux opioïdes suspectée est prise en charge au moyen d’une thérapie structurée aux opioïdes, d’un traitement à la méthadone ou à la buprénorphine ou encore d’un traitement fondé sur l’abstinence. Les patients souffrant de troubles de l’humeur ou d’anxiété ont tendance à avoir une réponse analgésique atténuée aux opioïdes, sont à risque plus élevé d’usage abusif et prennent souvent des sédatifs qui interagissent défavorablement avec les opioïdes. Il faut prendre des précautions semblables à celles utilisées avec d’autres patients à risque élevé. Il faut faire un sevrage progressif si la douleur du patient demeure sévère même avec un essai adéquat de thérapie aux opioïdes. Chez les personnes âgées, la s

  7. Relation entre les caractéristiques des table-bancs et les mesures anthropométriques des écoliers au Benin

    PubMed Central

    Falola, Stève Marjelin; Gouthon, Polycarpe; Falola, Jean-Marie; Fiogbe, Michel Armand; Nigan, Issiako Bio

    2014-01-01

    Introduction Le mobilier scolaire et la posture assise en classe sont souvent impliqués dans l'apparition des douleurs rachidiennes, influant de fait sur la qualité des tâches réalisées par les apprenants. Aucune étude n'a encore vérifié le degré d'adéquation entre les caractéristiques du mobilier et celles des écoliers au Bénin. L'objectif de cette étude transversale est donc de déterminer la relation entre les dimensions des table-bancs utilisées en classe et les mesures anthropométriques des écoliers au Bénin. Methods Elle a été réalisée avec un échantillon probabiliste de 678 écoliers, âgés de 4 à 17 ans. Les mesures anthropométriques des écoliers et les mensurations relatives aux longueurs, largeurs et hauteurs des table-bancs ont été mesurées, puis intégrées aux équations proposées dans la littérature. Les pourcentages des valeurs situées hors des limitesacceptables, dérivées de l'application des équations ont été calculés. Results La largeur et la hauteur des table-bancs utilisées par les écoliers étaient plus élevées (p < 0,05) que les valeurs de référence recommandées par les structures officielles de contrôle et de production des mobiliers scolaires au Bénin. Quel que soit le sexe, il y avait une inadéquation entre la largeur du banc et la longueur fesse-poplité, puis entre la hauteur de la table et la distance coude-bancdes écoliers. Conclusion Les résultats suggèrent de prendre en compte l’évolution des mesures anthropométriques des écoliers dans la confection des table-bancs, afin de promouvoir de bonnes postures assises en classe et de réduire le risque de troubles du rachis. PMID:25317232

  8. Croissance des couches minces et des multicouches de matériaux supraconducteurs H Tboldmath_c : bilan et perspective

    NASA Astrophysics Data System (ADS)

    Contour, J. P.

    1994-11-01

    The main physical and chemical techniques of epitaxial growth of High T_c superconductor thin films are described together with their in situ analysis facilities and discussed with respect to their cost, sophistication and results (T_c, J_c growth defects, thickness and composition uniformity, crystallinity, electronic applications...). The future trends of the growth machines are then examined in connection with the present results and the development of superconductor electronics. Après la présentation des principales techniques de croissance physique et physicochimique de couches minces d'oxydes supraconducteurs à haute température critique, un bilan des résultats sera dressé par rapport aux différentes propriétés des films (transition résistive, courant critique, défauts de croissance, uniformité d'épaisseur et de composition, cristallinité...), aux difficultés de mise en œuvre et au coût de l'expérience. Les perspectives des différentes techniques seront ensuite examinées dans le cadre du développement potentiel d'une électronique utilisant les matériaux supraconducteurs H T_c.

  9. Optimisation des proprietes fonctionnelles des alliages a memoire de forme suite a l'application de traitements thermomecaniques

    NASA Astrophysics Data System (ADS)

    Demers, Vincent

    L'objectif de ce projet est de determiner les conditions de laminage et la temperature de traitement thermique maximisant les proprietes fonctionnelles de l'alliage a memoire de forme Ti-Ni. Les specimens sont caracterises par des mesures de calorimetrie, de microscopie optique, de gene ration de contrainte, de deformation recuperable et des essais mecaniques. Pour un cycle unique, l'utilisation d'un taux d'ecrouissage e=1.5 obtenu avec l'application d'une force de tension FT = 0.1sigma y et d'une huile minerale resulte en un echantillon droit, sans microfissure et qui apres un recuit a 400°C, produit un materiau nanostructure manifestant des proprietes fonctionnelles deux fois plus grandes que le meme materiau ayant une structure polygonisee. Pour des cycles repetes, les memes conditions de laminage sont valables mais le niveau de deformation optimal est situe entre e=0.75-2, et depend particulierement du mode de sollicitation, du niveau de stabilisation et du nombre de cycles a la rupture requis par l'application.

  10. Dépistage des maladies cardiovasculaires chez des étudiants de l'Université de Douala et influence des activités physiques et sportives

    PubMed Central

    Ewane, Marielle Epacka; Mandengue, Samuel Honoré; Priso, Eugene Belle; Tamba, Stéphane Moumbe; Ahmadou; Fouda, André Bita

    2012-01-01

    Introduction Les maladies cardiovasculaires (MCV) constituent l'une des principales causes de mortalité dans les pays en développement. Le dépistage de ces dernières chez des jeunes est un défi dans la lutte contre leur expansion. Le but de cette étude était de dépister ces maladies au sein d'une population jeunes d’étudiants camerounais. Methodes Deux mille six cent cinquante-huit étudiants de l'Université de Douala (23,6 ± 2,9 ans, sex-ratio H/F = 0,9) ont en Avril - Mai 2011 participé à une campagne de dépistage gratuit du diabète, de l'hypertension artérielle (HTA) et de l'obésité. Ils ont également été soumis à une d'enquête évaluant leur niveau en activités physiques et sportives (APS). Resultats 12,7% des participants avaient une pression artérielle (PA) ≥ 140/90 mmHg, 3,6% étaient obèses et 0,9% avaient une glycémie ≥1,26 g/L. Des corrélations ont été trouvées entre certains facteurs de risque (diabète, hypertension et obésité) et le niveau académique d'une part (r =0,366; p < 0,0001) et le temps passé devant la télévision d'autres part (r = 0,411; p < 0,0001). L‘APS était inversement corrélée à l‘âge (r =-0,015; p < 0,0001) et au temps passé devant la télévision (r = -0,059; p = 0,002). Conclusion La présence des MCV et leurs facteurs de risque mis en évidence dans cette étude réalisée en milieu estudiantin camerounais interpelle à une prévention et une éducation dans la lutte contre ces dernières. PMID:22655111

  11. Evaluation des prescriptions antibiotiques au service des urgences de l’Hôpital Militaire d’Instruction Mohammed V (HMIMV)

    PubMed Central

    Elbouti, Anass; Rafai, Mostafa; Chouaib, Naoufal; Jidane, Said; Belkouch, Ahmed; Bakkali, Hicham; Belyamani, Lahcen

    2016-01-01

    Cette étude à pour objectifs de décrire les pratiques des prescriptions, évaluer leur pertinence et leur conformité aux règles d’utilisations et étudier les facteurs susceptibles de les influencer. Il s’agit d’une étude transversale d’évaluation des prescriptions antibiotiques portant sur 105 patients réalisée au service des urgences médico-chirurgicales de l’H.M.I.Med V de Rabat sur une période d’un mois. Le recueil des données était fait à l’aide d’un questionnaire rapportant les données démographiques et anamnestiques, les antécédents, la notion d’allergie, les données spécifiques de l’examen clinique, les données para cliniques, la prescription détaillée de l’antibiotique. Les données récoltées ont été ensuite évaluées par un médecin référent, chargé d’indiquer les éventuelles erreurs de traitement. Parmi les infections ayant motivé la prescription des antibiotiques, les affections des systèmes respiratoires et urinaires étaient au premier rang, les familles d’antibiotiques les plus couramment employées sont les pénicillines, les quinolones et les céphalosporines. 74 prescriptions soit (70,5%) étaient à la fois pertinentes et conformes contre 9 prescriptions soit (8,6%) justifiées mais non pertinentes et 6 prescriptions soit (5,7%) étaient jugées injustifiées par le médecin référent par absence d’infection. Les évaluations des pratiques médicales sont rarement menées dans les établissements de santé; c’est dans ce cadre que nous avons voulu nous inscrire en produisant cette étude afin d’améliorer la pertinence de nos prescriptions antibiotiques et d’optimiser leur conformité aux différentes recommandations. PMID:28292124

  12. Efficient reanalysis of structures by a direct modification method. [local stiffness modifications of large structures

    NASA Technical Reports Server (NTRS)

    Raibstein, A. I.; Kalev, I.; Pipano, A.

    1976-01-01

    A procedure for the local stiffness modifications of large structures is described. It enables structural modifications without an a priori definition of the changes in the original structure and without loss of efficiency due to multiple loading conditions. The solution procedure, implemented in NASTRAN, involved the decomposed stiffness matrix and the displacement vectors of the original structure. It solves the modified structure exactly, irrespective of the magnitude of the stiffness changes. In order to investigate the efficiency of the present procedure and to test its applicability within a design environment, several real and large structures were solved. The results of the efficiency studies indicate that the break-even point of the procedure varies between 8% and 60% stiffness modifications, depending upon the structure's characteristics and the options employed.

  13. 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

  14. Oxidative and other posttranslational modifications in extracellular vesicle biology.

    PubMed

    Szabó-Taylor, Katalin; Ryan, Brent; Osteikoetxea, Xabier; Szabó, Tamás G; Sódar, Barbara; Holub, Marcsilla; Németh, Andrea; Pálóczi, Krisztina; Pállinger, Éva; Winyard, Paul; Buzás, Edit I

    2015-04-01

    Extracellular vesicles including exosomes, microvesicles and apoptotic vesicles, are phospholipid bilayer surrounded structures secreted by cells universally, in an evolutionarily conserved fashion. Posttranslational modifications such as oxidation, citrullination, phosphorylation and glycosylation play diverse roles in extracellular vesicle biology. Posttranslational modifications orchestrate the biogenesis of extracellular vesicles. The signals extracellular vesicles transmit between cells also often function via modulating posttranslational modifications of target molecules, given that extracellular vesicles are carriers of several active enzymes catalysing posttranslational modifications. Posttranslational modifications of extracellular vesicles can also contribute to disease pathology by e.g. amplifying inflammation, generating neoepitopes or carrying neoepitopes themselves.

  15. Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

    PubMed Central

    Sun, Wen; Liu, Junxia; Chu, Huaqiang; Dong, Bingzhi

    2013-01-01

    The application of low pressure membranes (microfiltration/ultrafiltration) has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM). This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW) and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation) and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.). Perspectives of further research are also discussed. PMID:24956947

  16. Modifications of Glycans: Biological Significance and Therapeutic Opportunities

    PubMed Central

    Muthana, Saddam M.; Campbell, Christopher; Gildersleeve, Jeffrey C.

    2012-01-01

    Carbohydrates play a central role in a wide range of biological processes. As with nucleic acids and proteins, modifications of specific sites within the glycan chain can modulate a carbohydrate’s overall biological function. For example, acylation, methylation, sulfation, epimerization, and phosphorylation can occur at various positions within a carbohydrate to modulate bioactivity. Therefore, there is significant interest in identifying discrete carbohydrate modifications and understanding their biological effects. Additionally, enzymes that catalyze those modifications and proteins that bind modified glycans provide numerous targets for therapeutic intervention. This review will focus on modifications of glycans that occur after the oligomer/polymer has been assembled, generally referred to as postglycosylational modifications. PMID:22195988

  17. Surface Modifications in Adhesion and Wetting

    NASA Astrophysics Data System (ADS)

    Longley, Jonathan

    Advances in surface modification are changing the world. Changing surface properties of bulk materials with nanometer scale coatings enables inventions ranging from the familiar non-stick frying pan to advanced composite aircraft. Nanometer or monolayer coatings used to modify a surface affect the macro-scale properties of a system; for example, composite adhesive joints between the fuselage and internal frame of Boeing's 787 Dreamliner play a vital role in the structural stability of the aircraft. This dissertation focuses on a collection of surface modification techniques that are used in the areas of adhesion and wetting. Adhesive joints are rapidly replacing the familiar bolt and rivet assemblies used by the aerospace and automotive industries. This transition is fueled by the incorporation of composite materials into aircraft and high performance road vehicles. Adhesive joints have several advantages over the traditional rivet, including, significant weight reduction and efficient stress transfer between bonded materials. As fuel costs continue to rise, the weight reduction is accelerating this transition. Traditional surface pretreatments designed to improve the adhesion of polymeric materials to metallic surfaces are extremely toxic. Replacement adhesive technologies must be compatible with the environment without sacrificing adhesive performance. Silane-coupling agents have emerged as ideal surface modifications for improving composite joint strength. As these coatings are generally applied as very thin layers (<50 nm), it is challenging to characterize their material properties for correlation to adhesive performance. We circumvent this problem by estimating the elastic modulus of the silane-based coatings using the buckling instability formed between two materials of a large elastic mismatch. The elastic modulus is found to effectively predict the joint strength of an epoxy/aluminum joint that has been reinforced with silane coupling agents. This buckling

  18. Microscopie interférentielle X-UV : un outil pour l'étude des endommagements des surfaces optiques

    NASA Astrophysics Data System (ADS)

    Jamelot, G.; Ros, D.; Cassou, K.; Kazamias, S.; Klisnick, A.; Kozlová, M.; Mocek, T.; Homer, P.; Polan, J.; Stupka, M.

    2006-12-01

    Nous présentons des résultats récents concernant des premières investigations de microscopie interférentielle par laser X-UV d'endommagement optique. Le laser X-UV utilisé est un laser collisionnel en régime quasi-stationnaire émettant à 21.2 nm, développé au Prague Asterix Laser System (PALS, Prague, République Tchèque). Des échantillons de silice fondue de haute qualité, avec ou sans rayure, étaient irradiées en face avant par un laser bleu, correspondant au 3selectfontfontsize{7{9}{textrm{ème}}} harmonique du laser à iode du PALS (1.315 μ m), servant également à réaliser le laser X-UV à 21.2 nm. Celui-ci était utilisé, 5 ns après l'irradiation pour réaliser une imagerie microscopique et interférentielle de la face arrière de l'échantillon. Les résultats font apparaître des déformations locales transitoires. Des premières analyses mettent en évidence une probable variation de la rugosité de la surface. Cette démonstration expérimentale encourageante ouvre la voie à de futures investigations, notamment sur notre prochaine installation laser : LASERIX.

  19. Sleep Modifications in Acute Transient Global Amnesia

    PubMed Central

    Della Marca, Giacomo; Mazza, Marianna; Losurdo, Anna; Testani, Elisa; Broccolini, Aldobrando; Frisullo, Giovanni; Marano, Giuseppe; Morosetti, Roberta; Pilato, Fabio; Profice, Paolo; Vollono, Catello; Di Lazzaro, Vincenzo

    2013-01-01

    Study Objective: Transient global amnesia (TGA) is a temporary memory loss characterized by an abrupt onset of antero-grade and retrograde amnesia, totally reversible. Since sleep plays a major role in memory consolidation, and in the storage of memory-related traces into the brain cortex, the aims of the present study were: (1) to evaluate changes in sleep macro-structure in TGA; (2) to assess modifications in sleep micro-structure in TGA, with particular reference to the arousal EEG and to cyclic alternating pattern (CAP); (3) to compare sleep parameters in TGA patients with a control group of patients with acute ischemic events (“minor stroke” or transient ischemic attack [TIA]) clinically and neuroradiologically “similar” to the TGA. Methods: TGA group: 17 patients, (8 men and 9 women, 60.2 ± 12.5 years). Stroke or TIA (SoT) group: 17 patients hospitalized in the Stroke Unit for recent onset of minor stroke or TIA with hemispheric localization; healthy controls (HC) group: 17 healthy volunteers, matched for age and sex. Patients and controls underwent full-night polysomnography. Results: In the multivariate analysis (conditions TGA, SoT, and HC) a significant effect of the condition was observed for sleep efficiency index, number of awakenings longer 1 min, REM latency, CAP time, and CAP rate. TGA and SoT differed only for CAP time and CAP rate, which were lower in the TGA group. Conclusions: Microstructural modification associated with TGA could be consequent to: (1) hippocampal dysfunction and memory impairment; (2) impairment of arousal-related structures (in particular, cholinergic pathways); (3) emotional distress. Citation: Della Marca G; Mazza M; Losurdo A; Testani E; Broccolini A; Frisullo G; Marano G; Morosetti R; Pilato F; Profice P; Vollono C; Di Lazzaro V. Sleep modifications in acute transient global amnesia. J Clin Sleep Med 2013;9(9):921-927. PMID:23997704

  20. [TALE nuclease engineering and targeted genome modification].

    PubMed

    Shen, Yan; Xiao, An; Huang, Peng; Wang, Wei-Ye; Zhu, Zuo-Yan; Zhang, Bo

    2013-04-01

    Artificial designer nucleases targeting specific DNA sequences open up a new field for reverse genetics study. The rapid development of engineered endonucleases (EENs) enables targeted genome modification theoretically in any species. The construction of transcription activator-like effector nucleases (TALENs) is simpler with higher specificity and less toxicity than zinc-finger nucleases (ZFNs). Here, we summarized the recent progresses and prospects of TALEN technology, with an emphasis on its structure, function, and construction strategies, as well as a collection of species and genes that have been successfully modified by TALENs, especially the application in zebrafish.

  1. Near-blade flow structure modification

    NASA Astrophysics Data System (ADS)

    Kura, T.; Fornalik-Wajs, E.

    2016-10-01

    In this paper, the importance of near-blade flow structure influence on the performance of a centrifugal compressor was discussed. The negative effects of eddies and secondary flows appearance were described, together with the proposal of their reduction. Three-dimensional analyses were performed for the rotors. Focus was placed on the blade's 3D curvature impact on the efficiency of compression, and the influence of blade-shroud tip existence. A few design proposals were investigated - their performance maps were the basis of further analysis. Proposed modification of blade shape changed the near-blade flow structure and improved the compressor performance.

  2. Diesel particulate emission control without engine modifications

    SciTech Connect

    Filowitz, M.S.; Vataru, M.

    1989-01-01

    This paper describes an ashless, fuel supplement which was found to typically reduce diesel particulate emissions by over 30% while significantly improving fuel economy and power output without any modifications to existing diesel engines or fuels. The treating cost is an order of magnitude less than the estimated cost of reducing aromatic content at the refinery to achieve particulate reductions. The particulate reduction is virtually all from the carbon (soot) fraction. The reduced soot formation translates into less abrasives and less soot-loading stress on the engine oil. Diesel tests conducted are also discussed.

  3. ASPOD modifications of 1993-1994

    NASA Technical Reports Server (NTRS)

    Jackson, Jennifer J. (Editor); Fogarty, Paul W.; Muller, Matthew; Martucci, Thomas A., III; Williams, Daniel; Rowney, David A.

    1994-01-01

    ASPOD, Autonomous Space Processors for Orbital Debris, provides a unique way of collecting the space debris that has built up over the past 37 years. For the past several years, ASPOD has gone through several different modifications. This year's concentrations were on the solar cutting array, the solar tracker, the earth based main frame/tilt table, the controls for the two robotic arms, and accurate autocad drawings of ASPOD. This final report contains the reports written by the students who worked on the ASPOD project this year.

  4. Parent-Body Modification of Chondritic Meteorites

    NASA Technical Reports Server (NTRS)

    Rubin, Alan

    2003-01-01

    This proposal focused on the parent-body modification of chondritic materials and substantial progress was made in the last year. A summary of the work accomplished during this period is discussed. The topics include: 1) Chromite-Plagioclase Assemblages in Ordinary Chondrites; 2) The Gujba Bencubbin-like meteorite fall; 3) NWA428: A rock that Experienced Impact-induced Annealing; 4) Spade: An Annealed H-chondrite Impact-melt Breccia; and 5) Post-shock Annealing in Ordinary Chondrites. A list of the papers submitted or published during the period is also presented.

  5. Modifications of Fabrication of Vibratory Microgyroscopes

    NASA Technical Reports Server (NTRS)

    Bae, Sam Y.; Yee, Karl Y.; Wiberg, Dean

    2005-01-01

    A micromachining process for the fabrication of vibratory microgyroscopes from silicon wafers, and aspects of the microgyroscope design that are inextricably linked with the fabrication process, have been modified in an effort to increase production yields from perspectives of both quantity and quality. Prior to the modifications, the effective production yield of working microgyroscopes was limited to one or less per wafer. The modifications are part of a continuing effort to improve the design and increase production yields to more than 30 working microgyroscopes per wafer. A discussion of pertinent aspects of the unmodified design and the unmodified fabrication process is prerequisite to a meaningful description of the modifications. The design of the microgyroscope package was not conducive to high yield and rapid testing of many microgyroscopes. One of the major impediments to high yield and testing was found to lie in vibration- isolation beams around the four edges of each microgyroscope, which beams were found to be unnecessary for achieving high resonance quality factors (Q values) characterizing the vibrations of petallike cantilevers. The fabrication process included an 8- m-deep plasma etch. The purpose of the etch was to create 8- m vertical gaps, below which were to be placed large gold evaporated electrodes and sensing pads to drive and sense resonant vibrations of the "petals." The process also included a step in which bridges between dies were cut to separate the dies. The etched areas must be kept clean and smooth (free of debris and spikes), because any object close to 8 m high in those areas would stop the vibrations. However, it was found that after the etch, there remained some spikes with heights that were, variously, almost as high or as high as the etch depth. It also was found that the cutting of bridges created silicon debris, some of which lodged in the 8- m gaps and some of which landed on top of the petals. The masses added to the

  6. Methylation – an uncommon modification of glycans*

    PubMed Central

    Staudacher, Erika

    2013-01-01

    A methyl group on a sugar residue is a rarely reported event. Until now this kind of modification has been found in the kingdom of animals only in worms and molluscs, whereas it is more frequently present in some species of bacteria, fungi, algae and plants, but not in mammals. The monosaccharides involved as well as the positions of the methyl groups on the sugar vary with the species. Methylation seems to play a role in some recognition events but details are still unknown. This review summarises the current knowledge on methylation of sugars in all kinds of organism. PMID:22944672

  7. Post-Translational Modifications in Circadian Rhythms

    PubMed Central

    Mehra, Arun; Baker, Christopher L.; Loros, Jennifer J.; Dunlap, Jay C.

    2009-01-01

    The pace has quickened in circadian biology research. In particular, an abundance of results focused on post-translational modifications (PTMs) is sharpening our view of circadian molecular clockworks. PTMs affect nearly all aspects of clock biology; in some cases they are essential for clock function and in others, they provide layers of regulatory fine-tuning. Our goal is to review recent advances in clock PTMs, help make sense of emerging themes, and spotlight intriguing and perhaps controversial new findings. We focus on PTMs affecting the core functions of eukaryotic clocks, in particular the functionally related oscillators in Neurospora crassa, Drosophila melanogaster, and mammalian cells. PMID:19740663

  8. Epigenetic modification and cancer: mark or stamp?

    PubMed

    Foulkes, William D

    2012-04-01

    Hypotheses are built upon data, but data require hypotheses before they can be understood. The development of the 'two-hit' hypothesis of carcinogenesis was a key event in cancer genetics because it provided a testable model of how tumours develop. In this commentary on 'Promoter hypermethylation patterns in Fallopian tube epithelium of BRCA1 and BRCA2 germline mutation carriers' by Bijron et al. published in the February 2012 issue of Endocrine-Related Cancer, the need for new grammar and some new hypotheses in epigenetics is discussed. Meanwhile, data suggesting an important role of epigenetic modification in the cause, progression and treatment of cancer continues to accumulate.

  9. Ion beam modification of polyacetylene films

    NASA Astrophysics Data System (ADS)

    Lin, Senhao; Sheng, Kanglong; Bao, Jinrong; Rong, Tingwen; Zhou, Zhiyi; Zhang, Lanping; Zhu, Dezhang; Shen, Zhiquan; Yan, Mujie

    1989-03-01

    Low energy ion implantation of polyacetylene films synthesized with rare earth compound catalysts have been studied for potassium, sodium and iodine at the energy region of 15 to 30 keV. Film samples prepared in different ways, thermally treated and/or chemically doped, were irradiated up to 1 × 10 17 ions/cm 2. The resulting surface property modifications of the (CH) x films were examined by various kinds of techniques. Compensation effects of the dopants and electrical conductivity changes in the implanted regions were observed. Some of the implanted film samples exhibited diode like characteristics. Discussions on the experimental results are presented.

  10. Current profile modification during lower hybrid current drive in the Princeton Beta Experiment-Modification

    SciTech Connect

    Kaita, R.; Bell, R.; Batha, S.H.

    1996-02-01

    Current profile modification with lower hybrid waves has been demonstrated in the Princeton Beta Experiment-Modification tokamak. When the n{parallel} spectrum of the launched waves was varied, local changes in the current profile were observed according to equilibria reconstructed from motional Stark effect polarimetry measurements. Changes in the central safety factor (q) were also determined to be a function of the applied radio frequency (rf) power. These results have been modeled with the Tokamak Simulation Code/Lower Hybrid Simulation Code, which is able to duplicate the general trends seen in the data.

  11. Environmental modifications in the homes of elderly Canadians with disabilities.

    PubMed

    Fox, P L

    1995-01-01

    This study was performed to (1) determine if the use of architectural modifications in the homes of the disabled elderly can reduce the level of disability; (2) determine the predictors of the use of architectural modifications; and (3) estimate the degree of need for environmental modifications. The degree of need was estimated using data from 8895 respondents (55 years and older) from the Canadian Health and Disability Survey (1983-84). A subgroup of 1520 respondents who needed architectural modifications was selected to predict: (1) the ability to perform instrumental activities of daily living (IADL) and (2) the use of architectural modifications. These data were analysed using multiple linear regression. Approximately 37.9% of the disabled elderly required at least one modification to their home. About 40% did not have the architectural modification that was needed. Income was found to be a predictor of the use of architectural modifications (p = 0.0273). Users of architectural modifications were more independent in IADL than non-users (p < 0.0312). In conclusion, there is a substantial need for environmental modifications in the homes of the disabled elderly. Furthermore, architectural modifications should be available at a low cost.

  12. Chemical methods for encoding and decoding of posttranslational modifications

    PubMed Central

    Chuh, Kelly N.; Batt, Anna R.; Pratt, Matthew R.

    2016-01-01

    A large array of posttranslational modifications can dramatically change the properties of proteins and influence different aspects of their biological function such as enzymatic activity, binding interactions, and proteostasis. Despite the significant knowledge that has been gained about the function of posttranslational modifications using traditional biological techniques, the analysis of the site-specific effects of a particular modification, the identification of the full compliment of modified proteins in the proteome, and the detection of new types of modifications remains challenging. Over the years, chemical methods have contributed significantly in both of these areas of research. This review highlights several posttranslational modifications where chemistry-based approaches have made significant contributions to our ability to both prepare homogeneously modified proteins and identify and characterize particular modifications in complex biological settings. As the number and chemical diversity of documented posttranslational modifications continues to rise, we believe that chemical strategies will be essential to advance the field in years to come. PMID:26933738

  13. Transfer RNA modifications: Nature’s combinatorial chemistry playground

    PubMed Central

    Jackman, Jane E.; Alfonzo, Juan D.

    2012-01-01

    Following synthesis, tRNAs are peppered by numerous chemical modifications which may differentially affect a tRNA’s structure and function. Although modifications affecting the business ends of a tRNA are predictably important for cell viability, a majority of modifications play more subtle structural roles that can affect tRNA stability and folding. The current trend is that modifications act in concert and it is in the context of the specific sequence of a given tRNA that they impart their differing effects. Recent developments in the modification field have highlighted the diversity of modifications in tRNA. From these the combinatorial nature of modifications in explaining previously described phenotypes derived from their absence has emerged as a growing theme. PMID:23139145

  14. Mesure des stades de developpement du sapin baumier (Abies balsamea [L.] Mill.) par teledetection des maxima locaux sur images a tres haute resolution

    NASA Astrophysics Data System (ADS)

    Demers, Alain

    L'objectif principal de cette these est d'identifier les parametres cles pour lier le developpement morphologique de la cime du sapin baumier (Abies balsamea [L.] Mill.) aux patrons de reflectance qu'elle genere sur une image aerienne a haute resolution. La quantite et la distribution spatiale des aiguilles dans le sapin dependent de la structure des branches. Un mecanisme de ramification particulier (la reiteration) ressort comme le parametre cle pour lier l'augmentation de la biomasse foliaire et la forme de la branche. Les reiterats forment des agglomerats de feuillage qui engendrent des inegalites dans les patrons de reflectance de la cime. La reflectance est plus elevee ou il y a une forte concentration de reiterats (maximum local). On demontre que le developpement du sapin baumier se mesure au moyen de l'analyse des maxima locaux de la cime sur une image. La biomasse de l'arbre se mesure par la teledetection et l'analyse des patrons de reflectance de la cime, c'est-a-dire la mesure du niveau de reiteration par le decompte des maxima locaux de la cime. Cette etude demontre qu'il est possible de proceder a l'inventaire du volume de bois d'un peuplement par la teledetection de l'architecture des arbres.

  15. Current practices for modification of paving asphalts

    SciTech Connect

    Bahia, H.U.; Perdomo, D.

    1996-12-31

    The Superpave binder specification, AASHTO MP1, has introduced new concepts for selecting paving asphalt binders. The specification, in addition to using rheological and failure measurements that are more related to performance, is based on the idea that the criteria to maintain a satisfactory contribution of asphalt binders to the resistance of pavement failures remains the same but have to be satisfied at critical application temperatures. The test procedures require that the material be characterized within certain ranges of strains or stresses to ensure that material and geometric non-linearities are not confounded in the measurements. These new specification concepts have resulted in re-evaluation of asphalt modification by the majority of modified asphalt suppliers. The philosophy of asphalt modification is expected to change, following these new concepts, from a general improvement of quality to more focus on using modifiers based on the most critical need as defined by two factors: (1) The application temperature domain and (2) the type of distress to be remedied. The new specification requirements should result in a more effective use of modifiers as the amount and type of modifier will be directly related to the application environment and the engineering requirements.

  16. Studing cranial vault modifications in ancient Mesoamerica.

    PubMed

    Tiesler, Vera

    2012-01-01

    The artificial modification of infant cranial vaults through massages or by means of constriction and compression devices constitutes a readily visible, permanent body modification that has been employed cross-culturally to express identity, ethnicity, beauty, status and gender. For those ancient societies that staged head shaping, these cultural correlates may be ascertained by examining cranial shapes together with other data sets from the archaeological record. Studies of skulls modified for cultural reasons also provide important clues for understanding principles in neural growth and physiopathological variation in cranial expansion. This paper focuses on head shaping techniques in Mesoamerica, where the practice was deeply rooted and widespread before the European conquest. It provides a comprehensive review of the Mesoamericanistic research on shaping techniques, implements and taxonomies. An up-dated, interdisciplinary examination of the physiological implications and the cultural meanings of artificially produced head shapes in different times and culture areas within Mesoamerica leads to a discussion of the scope, caveats, and future directions involved in this kind of research in the region and beyond.

  17. Oxidative stress causes plasma protein modification.

    PubMed

    Tetik, Sermin; Kiliç, Arzu; Aksoy, Halil; Rizaner, Nahit; Ahmad, Sarfraz; Yardimci, Turay

    2015-01-01

    We investigated the effect of oxidative systems on plasma proteins using Chloramine-T, a source of free radicals. Plasma specimens from 10 healthy volunteers were treated with 40 mmol/L Chloramine-T (1:1 v/v). Total protein and plasma carbonyl levels were evaluated spectrophotometrically. Identification of plasma proteins modifications was performed by SDS-PAGE, protein and lipid electrophoresis. Protein fragmentation was evaluated by HPLC. Total protein levels of oxidised plasmas were significantly lower (4.08 ± 0.12 g/dL) than control (7.86 ± 0.03 g/dL) (P < 0.01). Plasma carbonyl levels were higher (1.94 ± 0.38 nmol/mg protein) in oxidised plasma than that of control (0.03 ± 0.01 nmol/mg protein) (P < 0.01). Plasma oxidation had no significant effect on the levels of proteins and lipids. Protein fragmentations were detected in oxidised groups compared to those of the control. We conclude that protein modifications have direct effect on the protein functions, which are related to stress agent, its treatment period(s), and the methodology used for evaluating such experimental results.

  18. Detection of thiol modifications by hydrogen sulfide.

    PubMed

    Williams, E; Pead, S; Whiteman, M; Wood, M E; Wilson, I D; Ladomery, M R; Teklic, T; Lisjak, M; Hancock, J T

    2015-01-01

    Hydrogen sulfide (H2S) is an important gasotransmitter in both animals and plants. Many physiological events, including responses to stress, have been suggested to involve H2S, at least in part. On the other hand, numerous responses have been reported following treatment with H2S, including changes in the levels of antioxidants and the activities of transcription factors. Therefore, it is important to understand and unravel the events that are taking place downstream of H2S in signaling pathways. H2S is known to interact with other reactive signaling molecules such as reactive oxygen species (ROS) and nitric oxide (NO). One of the mechanisms by which ROS and NO have effects in a cell is the modification of thiol groups on proteins, by oxidation or S-nitrosylation, respectively. Recently, it has been reported that H2S can also modify thiols. Here we report a method for the determination of thiol modifications on proteins following the treatment with biological samples with H2S donors. Here, the nematode Caenorhabditis elegans is used as a model system but this method can be used for samples from other animals or plants.

  19. Excimer laser surface modification: Process and properties

    SciTech Connect

    Jervis, T.R.; Nastasi, M.; Hirvonen, J.P.

    1992-12-01

    Surface modification can improve materials for structural, tribological, and corrosion applications. Excimer laser light has been shown to provide a rapid means of modifying surfaces through heat treating, surface zone refining, and mixing. Laser pulses at modest power levels can easily melt the surfaces of many materials. Mixing within the molten layer or with the gas ambient may occur, if thermodynamically allowed, followed by rapid solidification. The high temperatures allow the system to overcome kinetic barriers found in some ion mixing experiments. Alternatively, surface zone refinement may result from repeated melting-solidification cycles. Ultraviolet laser light couples energy efficiently to the surface of metallic and ceramic materials. The nature of the modification that follows depends on the properties of the surface and substrate materials. Alloying from both gas and predeposited layer sources has been observed in metals, semiconductors, and ceramics as has surface enrichment of Cr by zone refinement of stainless steel. Rapid solidification after melting often results in the formation of nonequilibrium phases, including amorphous materials. Improved surface properties, including tribology and corrosion resistance, are observed in these materials.

  20. Posttranslational Modifications and the Immunogenicity of Biotherapeutics

    PubMed Central

    Jefferis, Roy

    2016-01-01

    Whilst the amino acid sequence of a protein is determined by its gene sequence, the final structure and function are determined by posttranslational modifications (PTMs), including quality control (QC) in the endoplasmic reticulum (ER) and during passage through the Golgi apparatus. These processes are species and cell specific and challenge the biopharmaceutical industry when developing a production platform for the generation of recombinant biologic therapeutics. Proteins and glycoproteins are also subject to chemical modifications (CMs) both in vivo and in vitro. The individual is naturally tolerant to molecular forms of self-molecules but nonself variants can provoke an immune response with the generation of anti-drug antibodies (ADA); aggregated forms can exhibit enhanced immunogenicity and QC procedures are developed to avoid or remove them. Monoclonal antibody therapeutics (mAbs) are a special case because their purpose is to bind the target, with the formation of immune complexes (ICs), a particular form of aggregate. Such ICs may be removed by phagocytic cells that have antigen presenting capacity. These considerations may frustrate the possibility of ameliorating the immunogenicity of mAbs by rigorous exclusion of aggregates from drug product. Alternate strategies for inducing immunosuppression or tolerance are discussed. PMID:27191002

  1. Epigenetic Modifications and Therapy in Multiple Sclerosis.

    PubMed

    Aslani, Saeed; Jafari, Naser; Javan, Mohammad Reza; Karami, Jafar; Ahmadi, Majid; Jafarnejad, Mahmoud

    2017-03-01

    Breakthroughs in genetic studies, like whole human genome sequencing and genome-wide association studies (GWAS), have richened our knowledge of etiopathology of autoimmune diseases (AID) through discovery of genetic patterns. Nonetheless, the precise etiology of autoimmune diseases remains largely unknown. The lack of complete concordance of autoimmune disease in identical twins suggests that non-genetic factors also play a major role in determining disease susceptibility. Although there is no certain definition, epigenetics has been known as heritable alterations in gene function without changes in the nucleotide sequence. DNA methylation, histone modifications, and microRNA-associated gene expression suppression are the central mechanisms for epigenetic regulations. Multiple sclerosis (MS) is a disorder of the central nervous system (CNS), characterized by both inflammatory and neurodegenerative features. Although studies on epigenetic alterations in MS only began in the past decade, a mounting number of surveys suggest that epigenetic changes may be involved in the initiation and development of MS, probably through bridging the effects of environmental risk factors to genetics. Arming with clear understanding of epigenetic dysregulations underpins development of epigenetic therapies. Identifying agents inhibiting the enzymes controlling epigenetic modifications, particularly DNA methyltransferases and histone deacetylases, will be promising therapeutic tool toward MS. In the article underway, it is aimed to go through the recent progresses, attempting to disclose how epigenetics associates with the pathogenesis of MS and how can be used as therapeutic approach.

  2. Epigenetic modification of OXT and human sociability

    PubMed Central

    Haas, Brian W.; Filkowski, Megan M.; Cochran, R. Nick; Denison, Lydia; Ishak, Alexandra; Nishitani, Shota; Smith, Alicia K.

    2016-01-01

    Across many mammalian species there exist genetic and biological systems that facilitate the tendency to be social. Oxytocin is a neuropeptide involved in social-approach behaviors in humans and others mammals. Although there exists a large, mounting body of evidence showing that oxytocin signaling genes are associated with human sociability, very little is currently known regarding the way the structural gene for oxytocin (OXT) confers individual differences in human sociability. In this study, we undertook a comprehensive approach to investigate the association between epigenetic modification of OXT via DNA methylation, and overt measures of social processing, including self-report, behavior, and brain function and structure. Genetic data were collected via saliva samples and analyzed to target and quantify DNA methylation across the promoter region of OXT. We observed a consistent pattern of results across sociability measures. People that exhibit lower OXT DNA methylation (presumably linked to higher OXT expression) display more secure attachment styles, improved ability to recognize emotional facial expressions, greater superior temporal sulcus activity during two social-cognitive functional MRI tasks, and larger fusiform gyrus gray matter volume than people that exhibit higher OXT DNA methylation. These findings provide empirical evidence that epigenetic modification of OXT is linked to several overt measures of sociability in humans and serve to advance progress in translational social neuroscience research toward a better understanding of the evolutionary and genetic basis of normal and abnormal human sociability. PMID:27325757

  3. Reproductibilité des classifications OMS 1973 et OMS 2004 des tumeurs urothéliales papillaires de la vessie

    PubMed Central

    Ben Abdelkrim, Soumaya; Rammeh, Soumaya; Trabelsi, Amel; Ben Yacoub-Abid, Lilia; Ben Sorba, Nabil; Jaïdane, Lilia; Mokni, Moncef

    2012-01-01

    Résumé Objectif : Déterminer les taux d’accord et la reproductibilité intra et inter-observateurs des classifications OMS 1973 et OMS 2004 des tumeurs urothéliales papillaires de la vessie. Matériel et méthodes : Cent deux cas de tumeurs urothéliales papillaires de stade pTa/pT1 ont été étudiés. Deux pathologistes ont revu les lames et ont établi le grade tumoral selon les deux classifications OMS 1973 et OMS 2004. En cas de désaccord, les deux évaluateurs ont procédé à une lecture commune au microscope en double tête afin d’aboutir à un grade consensuel selon les deux classifications. La variabilité intra-observateur a été étudiée chez l’un des deux évaluateurs qui a procédé à la relecture des lames un mois après sa première lecture. Les taux d’accord entre les deux pathologistes pour chaque catégorie de grade ont été déterminés et la reproductibilité des deux classifications a été évaluée à l’aide du coefficient kappa. Une valeur de 0 à 0,2 était interprétée comme un désaccord absolu, de 0,21 à 0,4, un accord faible, de 0,41 à 0,6, un accord modéré, de 0,61 à 0,8, un accord considérable, et de 0,8 à 1, un accord absolu. Résultats : Selon la classification OMS 1973, les proportions des grades G1, G2 et G3 étaient respectivement de 40,2 %, 50 % et 9,8 %. Selon la classification OMS 2004, les proportions respectives des tumeurs de faible potentiel de malignité, des carcinomes de bas grade et des carcinomes de haut grade de malignité étaient de 23,5 %, 60,8 % et 15,7 %. La reproductibilité intra-observateur était excellente pour les deux classifications (accord absolu). Les taux d’accord entre les deux pathologistes étaient meilleurs pour la classification OMS 2004 (kappa = 0,7) que pour la classification OMS 1973 (kappa = 0,51). Conclusions : La reproductibilité entre observateurs de la classification OMS 2004 est supérieure à celle de 1973. La reproductibilité intra-observateur est

  4. Prise en charge des troubles de consommation d’opioïdes en première ligne

    PubMed Central

    Srivastava, Anita; Kahan, Meldon; Nader, Maya

    2017-01-01

    Résumé Objectif Conseiller les médecins quant aux options thérapeutiques à recommander à des populations précises de patients : approche axée sur l’abstinence, traitement d’entretien par la buprénorphine-naloxone ou traitement d’entretien par la méthadone. Sources d’information Une recherche sur PubMed a été effectuée, et on a relevé dans les publications les données sur l’efficacité, l’innocuité et le profil d’effets indésirables de l’approche axée sur l’abstinence, du traitement par la buprénorphine-naloxone et du traitement par la méthadone. Les études d’observation et interventionnelles ont été incluses. Message principal La méthadone et la buprénorphine-naloxone sont substantiellement plus efficaces que l’approche axée sur l’abstinence. La méthadone présente un taux de rétention plus élevé que la buprénorphine-naloxone, alors que la buprénorphine-naloxone présente un risque plus faible de surdose. Les médecins devraient recommander le traitement par la méthadone ou la buprénorphine-naloxone plutôt que l’approche axée sur l’abstinence, et ce, à tous les groupes de patients (données de niveau I). La méthadone est préférable à la buprénorphine-naloxone chez les patients qui présentent un risque élevé d’abandon, comme les usagers d’opioïdes par injection (données de niveau I). Les jeunes et les femmes enceintes qui font usage d’opioïdes par injection devraient aussi recevoir la méthadone d’abord (données de niveau III). Si la buprénorphine-naloxone est prescrite en premier, il faut faire passer rapidement le patient à la méthadone si les symptômes de sevrage, les fortes envies ou la consommation d’opioïdes persistent malgré une dose optimale de buprénorphine-naloxone (données de niveau II). La buprénorphine-naloxone est recommandée chez les usagers d’opioïdes sur ordonnance par voie orale socialement stables, surtout s’ils ont un emploi ou si leurs

  5. Polydopamine-based surface modification of mesoporous silica nanoparticles as pH-sensitive drug delivery vehicles for cancer therapy.

    PubMed

    Chang, Danfeng; Gao, Yongfeng; Wang, Lijun; Liu, Gan; Chen, Yuhan; Wang, Teng; Tao, Wei; Mei, Lin; Huang, Laiqiang; Zeng, Xiaowei

    2016-02-01

    A novel pH-sensitive drug delivery system of mesoporous silica nanoparticles (MSNs) which were modified by polydopamine (PDA) for controlled release of cationic amphiphilic drug desipramine (DES) was prepared. MSNs-DES-PDA were characterized in terms of size, size distribution, surface morphology, BET surface area, mesoporous size and pore volume, drug loading content and in vitro drug release profile. MSNs-DES-PDA had high drug loading content and pH sensitivity. The DES release profiles of MSNs-DES and MSNs-DES-PDA were totally different, and the drug release of MSNs-DES-PDA accelerated with increasing acidity. MSNs-DES-PDA can be internalized into cells. In vitro experiments demonstrated that MSNs-DES-PDA had higher cytotoxicity and inhibitory effects on acid sphingomyelinase than those of free DES. This drug delivery system was beneficial for controlled release and cancer therapy.

  6. Heterogeneous polymer modification: Polyolefin maleation in supercritical carbon dioxide and amorphous fluoropolymer surface modification

    NASA Astrophysics Data System (ADS)

    Hayes, Heather J.

    1999-11-01

    Three distinct heterogeneous polymer modification reactions are explored in this work. The first is a bulk reaction commonly conducted on polyolefins---the free radical addition of maleic anhydride. This reaction was run using supercritical carbon dioxide (SC CO2) as the solvent. The second was the chemical surface modification of an amorphous fluorocopolymer of tetrafluoroethylene and a perfluorodioxole monomer (Teflon AF). Several reactions were explored to reduce the surface of the fluorocopolymer for the enhancement of wettability. The last modification was also on Teflon AF and involved the physical modification of the surface through the transport polymerization of xylylene in order to synthesize a novel bilayer membrane. The bulk maleation of poly-4-methyl-1-pentene (PMP) was the focus of the first project. SC CO2 was utilized as both solvent and swelling agent to promote this heterogeneous reaction and led to successful grafting of anhydride groups on both PMP and linear low density polyethylene. Varying the reaction conditions and reagent concentrations allowed optimization of the reaction. The grafted anhydride units were found to exist as single maleic and succinic grafts, and the PMP became crosslinked upon maleation. The surface of a fluoropolymer can be difficult to alter. An examination of three reactions was made to determine the reactivity of Teflon AF: sodium naphthalenide treatment (Na-Nap), aluminum metal modification through deposition and dissolution, and mercury/ammonia photosensitization. The fluorocopolymer with the lower perfluorodioxole percentage was found to be more reactive towards modification with the Na-Nap treatment. The other modification reactions appeared to be nearly equally reactive toward both fluorocopolymers. The functionality of the Na-Nap-treated surface was examined in detail with the use of several derivatization reactions. In the final project, an asymmetric gas separation membrane was synthesized using Teflon AF as

  7. Prise en charge des complications des fistules artério-veineuses pour hémodialyse chronique

    PubMed Central

    Jiber, Hamid; Zrihni, Youssef; Zaghloul, Rachid; Hajji, Rita; Zizi, Othman; Bouarhroum, Abdellatif

    2015-01-01

    La fistule artério-veineuse native est l'accès vasculaire de choix pour l'hémodialyse chronique en raison de sa longévité, son taux faible de complication et de mortalité par rapport aux pontages artério-veineux et aux cathéters. Cependant, il arrive assez souvent que l'on assiste à des complications qui sont dominées par la sténose et la thrombose. C'est une étude rétrospective des complications ayants survenues pour 31 fistules artério-veineuses pour hémodialyse chronique des 200 fistules réalisées chez 200 patients au sein du service de chirurgie vasculaire du CHU Hassan II de Fès sur une période de trois ans, étendue de Janvier 2007 à Décembre 2009. Ces complications ont été présentés par les thromboses dans 14 cas soit 45,15% de l'ensemble des complications, les sténoses dans 4 cas (12,90%,) les anévrismes dans 4 cas (12,90%), les complications ischémiques dans 3 cas (9,67%), l'infection dans 3 cas (9,67%), l'hémorragie dans 2 cas (6,45%) et l’ hyperdébit dans un seul cas soit 3,22%. On a pu conserver 22 fistules soit 70,96% par traitement chirurgical ou endovasculaire, on a confectionné une nouvelle fistule dans 8 cas soit 25,80%, et on a adressé une patiente (3,22%) pour pose d'un cathéter veineux tunnelisé permanent. Les complications des fistules artério-veineuses pour l'hémodialyse chronique sont la principale cause de morbidité chez les patients hémodialysés, il est donc important de s'impliquer lors de leur création, et de donner un maximum d'attention quand ils sont manipulés. Ceci suggère la mise en place d'un programme de surveillance de ces fistules en raison de l'impact des complications sur la morbi-mortalité du patient hémodialysé et sur le plan financier. PMID:26113933

  8. Acupuncture Au Laser He-Ne: Traitement Des Infections Rhinopharyngees

    NASA Astrophysics Data System (ADS)

    Dussert, Dr.

    1984-03-01

    Mesdames, Messieurs, y a 23 mois, je recevais l'urgence suivante dans mon cabinet medical : 1) Un homme de 53 ans, dyspneioue (cliniquement it etait en Bradypnee expiratoire). Il venait d'être hospitalise 1 mois et avait ete place sous cortisone. Je le fais assoir, et j'irradie avec un laser sur chacun des ganglions stellaires pendant 6 minutes je debloque ce malade qui se met e respirer normalement. 2) Quelques temps apres : C'est un enfant de 7 ans que je regois en crise d'asthme. J'irradie sur chacun des ganglions stellaires pendant 4 minutes une onde laser d'impulsion 6 et en basse freouence. L'enfant voit s'estomper la crise d'asthme. Devant ces deux cas, je decide d'organiser un travail de recherche.

  9. The DES Science Verification Weak Lensing Shear Catalogs

    SciTech Connect

    Jarvis, M.

    2016-05-01

    We present weak lensing shear catalogs for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogs of 2.12 million and 3.44 million galaxies respectively. We also detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SV data. Furthermore, we discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogs for the full 5-year DES, which is expected to cover 5000 square degrees.

  10. The DES Science Verification weak lensing shear catalogues

    NASA Astrophysics Data System (ADS)

    Jarvis, M.; Sheldon, E.; Zuntz, J.; Kacprzak, T.; Bridle, S. L.; Amara, A.; Armstrong, R.; Becker, M. R.; Bernstein, G. M.; Bonnett, C.; Chang, C.; Das, R.; Dietrich, J. P.; Drlica-Wagner, A.; Eifler, T. F.; Gangkofner, C.; Gruen, D.; Hirsch, M.; Huff, E. M.; Jain, B.; Kent, S.; Kirk, D.; MacCrann, N.; Melchior, P.; Plazas, A. A.; Refregier, A.; Rowe, B.; Rykoff, E. S.; Samuroff, S.; Sánchez, C.; Suchyta, E.; Troxel, M. A.; Vikram, V.; Abbott, T.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Clampitt, J.; Crocce, M.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Fausti Neto, A.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gaztanaga, E.; Gerdes, D. W.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; March, M.; Martini, P.; Miquel, R.; Mohr, J. J.; Neilsen, E.; Nord, B.; Ogando, R.; Reil, K.; Romer, A. K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Walker, A. R.; Wechsler, R. H.

    2016-08-01

    We present weak lensing shear catalogues for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogues of 2.12 million and 3.44 million galaxies, respectively. We detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SV data. We also discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogues for the full 5-yr DES, which is expected to cover 5000 square degrees.

  11. The DES Science Verification Weak Lensing Shear Catalogs

    DOE PAGES

    Jarvis, M.

    2016-05-01

    We present weak lensing shear catalogs for 139 square degrees of data taken during the Science Verification (SV) time for the new Dark Energy Camera (DECam) being used for the Dark Energy Survey (DES). We describe our object selection, point spread function estimation and shear measurement procedures using two independent shear pipelines, IM3SHAPE and NGMIX, which produce catalogs of 2.12 million and 3.44 million galaxies respectively. We also detail a set of null tests for the shear measurements and find that they pass the requirements for systematic errors at the level necessary for weak lensing science applications using the SVmore » data. Furthermore, we discuss some of the planned algorithmic improvements that will be necessary to produce sufficiently accurate shear catalogs for the full 5-year DES, which is expected to cover 5000 square degrees.« less

  12. Des recommandations probantes pour surveiller l’innocuité des antipsychotiques de deuxième génération chez les enfants et les adolescents

    PubMed Central

    Pringsheim, Tamara; Panagiotopoulos, Constadina; Davidson, Jana; Ho, Josephine

    2012-01-01

    HISTORIQUE : Au Canada, l’utilisation d’antipsychotiques, notamment les antipsychotiques de deuxième génération (ADG), a augmenté de façon considérable depuis cinq ans chez les enfants ayant des troubles de santé mentale. Ces médicaments ont le potentiel de causer de graves complications métaboliques et neurologiques lorsqu’on les utilise de manière chronique. OBJECTIF : Synthétiser les données probantes relatives aux effets secondaires métaboliques et neurologiques précis associés à l’usage d’ADG chez les enfants et fournir des recommandations probantes sur la surveillance de ces effets secondaires. MÉTHODOLOGIE : Les auteurs ont procédé à une analyse systématique des essais cliniques contrôlés des ADG auprès d’enfants. Ils ont fait des recommandations à l’égard de la surveillance de l’innocuité des ADG d’après un modèle de classification fondé sur le système GRADE (système de notation de l’évaluation et de l’élaboration des recommandations). Lorsque les données probantes n’étaient pas suffisantes, ils fondaient leurs recommandations sur le consensus et l’avis d’experts. Un groupe consensuel multidisciplinaire a analysé toutes les données probantes pertinentes et est parvenu à un consensus à l’égard des recommandations. RÉSULTATS : Les recommandations probantes portant sur la surveillance de l’innocuité des ADG figurent dans les présentes lignes directrices. Les auteurs indiquent la qualité des recommandations relatives à des examens physiques et tests de laboratoire précis à l’égard de chaque ADG à des moments déterminés. CONCLUSION : De multiples essais aléatoires et contrôlés ont permis d’évaluer l’efficacité de bon nombre des ADG utilisés pour traiter les troubles de santé mentale en pédiatrie. Toutefois, leurs avantages ne sont pas sans risques : on observe à la fois des effets secondaires métaboliques et neurologiques chez les enfants traités au moyen d

  13. Partager : des technologies de pointe au service de la société

    ScienceCinema

    None

    2016-07-12

    Médecine, climatologie, métrologie et informatique, les techniques utilisées par le LHC trouvent déjà des répercussions dans d’autres domaines scientifiques. Utilisant des techniques inédites, la physique des particules en fait bénéficier la société toute entière.

  14. Gestion des plaines inondables: Hauteur ou débit

    NASA Astrophysics Data System (ADS)

    El-Jabi, Nassir; Rousselle, Jean

    1983-07-01

    A stochastic model based on the recent developments in the theory of extreme values is presented to describe the flood occurrence. This model is applied to the "Rivière des Prairies", assuming that the exceedances (flood peak and/or stage above a given base flow and/or base stage) are independent and identically distributed in the time interval for a given year and season.

  15. Landform Variability in the Chaine Des Puys Tracing Multiple Processes

    NASA Astrophysics Data System (ADS)

    van Wyk de Vries, B.; Grosse, P.

    2014-12-01

    The Chaîne des Puys is a highly varied, type monogenetic field, and was acknowledged by 38th WH UNESCO Committee to contain Outstanding Universal Value. The Chaîne des Puys - Limagne Fault should be presented in 2016 for World Heritage Status. The 30 km long Chaîne des Puys contains ranges from simple basaltic scoria cones to complex, multicrater cones, and small simple domes to complicated trachytic edifices. There is also a range of phreatomagmatic landforms from tuff rings to maars and vulcanian to sub plinian deposits. There is a wide range of pahoehoe and aa lava types, that have flowed over different topographies. Here we take morphometrical data to analyse the variability of the edifices using a 10 m regional topographic DTM. The volcanoes form a broad continuum of morphological features, and height/widths of domes and cones overlap. Some edifices, are smooth and elliptical, even though they have erupted complex lava sequences, while others complex shapes, but are related to simple lava flows. There seems to be no easy correlation between cone morphology and eruption histories derived from lava fields and distal tephras. In the few cones where the interior is visible, the shape of the cone is seen to vary with changing eruption events. The final shape is a combination of changing activity, with the last events having the strongest morphometic signature. The broad variations in edifice, lava field, and deposit morphology are described and quantified, however it becomes clear from the few individual eruptions already studied, that to fully appreciate the range of monogenetic eruption scenarios presented by the Chaîne des Puys, much more detailed work is required. This is being made possible by new acquisitions of LiDAR imagery, new geophysical work, and the combination of excellent preservation and extensive outcrop that is partly the result the original geology and long term responsible land management by the local populace, regional park and local

  16. La dysplasie fibreuse: état des lieux

    PubMed Central

    Akasbi, Nessrine; Abourazzak, Fatima Ezzahra; Talbi, Sofia; Tahiri, Latifa; Harzy, Taoufik

    2015-01-01

    La dysplasie fibreuse des os est une affection osseuse bénigne congénitale mais non héréditaire, où l'os normal est remplacé par un tissu fibreux renfermant une ostéogenèse immature. Elle est due à une mutation du gène GNAS 1sur le chromosome 20q13, une mutation activatrice de la sous-unité α de la protéine G. C'est une pathologie qui est le plus souvent silencieuse, de découverte fortuite sur une radiographie standard ou révélée par une douleur osseuse ou une fracture pathologique. L'imagerie et l'histologie, quand elle est nécessaire, permettent d’établir le diagnostic. Bien qu'il ne s'agisse pas d'une tumeur, elle est souvent classée dans la catégorie des tumeurs osseuses bénignes pour des raisons de diagnostic différentiel radiographique et anatomopathologique. Elle peut être monostotique ou polyostotique. L'approche thérapeutique est essentiellement symptomatique. Quelques publications récentes ont suggéré l'intérêt majeur d'un bisphosphonate, en particulier le pamidronate, qui diminuerait les douleurs et stimulerait une reminéralisation progressive des zones ostéolytiques chez les patients traités. D'autres traitements tels que la thérapie ciblée sont en cours d’évaluation. PMID:26401215

  17. Discovery and Classification of DES15E1iuh

    NASA Astrophysics Data System (ADS)

    Smith, M.; Sullivan, M.; Childress, M.; D'Andrea, C.; Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; 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.

    2015-10-01

    We report optical spectroscopy of DES15E1iuh discovered by the Dark Energy Survey. We obtained spectra using the X-SHOOTER instrument (wavelength range 380-950nm) on the Very Large Telescope (VLT) of the European Southern Observatory (ESO) and the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389; wavelength range 370-885nm) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  18. Simulations of the OzDES AGN reverberation mapping project

    DOE PAGES

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; ...

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrainmore » the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.« less

  19. Discovery and Classification of DES15S2lam

    NASA Astrophysics Data System (ADS)

    Pan, Y.-C.; Foley, R. J.; 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.; 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.

    2015-10-01

    We report optical spectroscopy of DES15S2lam discovered by the Dark Energy Survey. The spectrum (540-965nm) was obtained using GMOS on Gemini-North. Object classification was performed using superfit (Howell et al, 2005, ApJ, 634, 1190) and SNID (Blondin & Tonry, 2007, ApJ, 666, 1024), the details of which are reported in the table below.

  20. Probing the primordial Universe with MeerKAT and DES

    NASA Astrophysics Data System (ADS)

    Fonseca, José; Maartens, Roy; Santos, Mário G.

    2017-04-01

    It is usually assumed that we will need to wait until next-generation surveys like Euclid, LSST and SKA, in order to improve on the current best constraints on primordial non-Gaussianity from the Planck experiment. We show that two contemporary surveys, with the SKA precursor MeerKAT and the Dark Energy Survey (DES), can be combined using the multitracer technique to deliver an accuracy on measurement of fNL that is up to three times better than Planck.

  1. CMB lensing tomography with the DES Science Verification galaxies

    DOE PAGES

    Giannantonio, T.

    2016-01-07

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of themore » signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the LCDM Planck cosmology, a 1.7σ deviation.« less

  2. CMB lensing tomography with the DES Science Verification galaxies

    SciTech Connect

    Giannantonio, T.

    2016-01-07

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of the signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the LCDM Planck cosmology, a 1.7σ deviation.

  3. CMB lensing tomography with the DES Science Verification galaxies

    NASA Astrophysics Data System (ADS)

    Giannantonio, T.; Fosalba, P.; Cawthon, R.; Omori, Y.; Crocce, M.; Elsner, F.; Leistedt, B.; Dodelson, S.; Benoit-Lévy, A.; Gaztañaga, E.; Holder, G.; Peiris, H. V.; Percival, W. J.; Kirk, D.; Bauer, A. H.; Benson, B. A.; Bernstein, G. M.; Carretero, J.; Crawford, T. M.; Crittenden, R.; Huterer, D.; Jain, B.; Krause, E.; Reichardt, C. L.; Ross, A. J.; Simard, G.; Soergel, B.; Stark, A.; Story, K. T.; Vieira, J. D.; Weller, J.; Abbott, T.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Banerji, M.; Bernstein, R. A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Carlstrom, J. E.; Carnero Rosell, A.; Carrasco Kind, M.; Castander, F. J.; Chang, C. L.; Cunha, C. E.; da Costa, L. N.; D'Andrea, C. B.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Evrard, A. E.; Neto, A. Fausti; Fernandez, E.; Finley, D. A.; Flaugher, B.; Frieman, J.; Gerdes, D.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Holzapfel, W. L.; Honscheid, K.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; March, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sako, M.; Saliwanchik, B. R.; Sanchez, E.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Zuntz, J.

    2016-03-01

    We measure the cross-correlation between the galaxy density in the Dark Energy Survey (DES) Science Verification data and the lensing of the cosmic microwave background (CMB) as reconstructed with the Planck satellite and the South Pole Telescope (SPT). When using the DES main galaxy sample over the full redshift range 0.2 < zphot < 1.2, a cross-correlation signal is detected at 6σ and 4σ with SPT and Planck , respectively. We then divide the DES galaxies into five photometric redshift bins, finding significant (>2σ) detections in all bins. Comparing to the fiducial Planck cosmology, we find the redshift evolution of the signal matches expectations, although the amplitude is consistently lower than predicted across redshift bins. We test for possible systematics that could affect our result and find no evidence for significant contamination. Finally, we demonstrate how these measurements can be used to constrain the growth of structure across cosmic time. We find the data are fit by a model in which the amplitude of structure in the z < 1.2 universe is 0.73 ± 0.16 times as large as predicted in the Λ cold dark matter Planck cosmology, a 1.7σ deviation.

  4. Infections fongiques des brûlé : revue

    PubMed Central

    Arnould, JF.; Le Floch, R.

    2015-01-01

    Summary Les infections fongiques locales ou générales sont souvent d’une extrême gravité chez les brûlés. Les brûlés combinent de nombreux facteurs de risque à une immunodépression induite par la brûlure. Les infections de plaies sont le fait des genres Candida, Aspergillus et des agents de mucormycoses. Ces deux derniers cas sont à l’origine de lésions particulièrement sévères. Leur diagnostic repose sur la biopsie cutanée avec examens mycologique et anatomopathologique. Le traitement est essentiellement chirurgical, associé à une antibiothérapie adaptée. Les septicémies sont le fait de levures, essentiellement du genre Candida. Le diagnostic en est difficile dans le contexte des brûlés et repose souvent sur une forte suspicion clinique. Leur traitement repose sur les échinocandines et plus secondairement sur le fluconazole. PMID:26668558

  5. Excrétion rénale des ions divalents après homotransplantation rénale

    PubMed Central

    Cartier, F.; Popovtzer, M. M.; Robinette, J.; Pinggera, W. F.; Halgrimson, C. G.; Starzl, T. E.

    2010-01-01

    RÉSUMÉ L’élimination rénale des ions divalents, celle du Na et du K, ont été étudiées de façon comparative dans les suites immédiates de l’homotransplantation rénale chez 6 patients. Durant la période initiale polyurique (> 3ml/mn), le taux d’excrétion du Ca filtré (Cca/Ccr), du Mg, du P, du Na et du K, est élevé et il existe une corrélation étroite et quasi constante entre l’élimination du Ca, du Mg et du Na ; la corrélation n’est pas constante entre l’élimination du Na et du K, du Mg et du K. Pendant les deux jours suivants, le taux d’excrétion diminue, sauf pour le P ; il existe encore une corrélation entre l’excrétion du Ca, du Mg et du Na, non entre celle du Na et du K, du Mg et du K. L’excrétion du Ca l’emporte sur celle du Na au cours de la première période, non au cours de la seconde. A la lumière de ces données, on envisage l’intervention possible de divers facteurs, tels l’inflation hydrosique et l’hyperazotémie préalables, l’ischémie rénale contemporaine de la transplantation, les effets de la dénervation rénale, du traitement cortisonique, de l’hyperparathyroïdie et ceux des modifications circulatoires rénales. PMID:4574592

  6. Approche à l’endroit des blessures traumatiques à la main en soins primaires

    PubMed Central

    Cheung, Kevin; Hatchell, Alexandra; Thoma, Achilleas

    2013-01-01

    Résumé Objectif Passer en revue la prise en charge initiale des blessures traumatiques communes à la main que voient les médecins de soins primaires. Sources des données Nous avons examiné les données cliniques probantes et les ouvrages spécialisés récents cernés par des recherches dans la base de données électronique MEDLINE. Nous avons utilisé l’opinion d’experts pour compléter les recommandations dans les domaines où les données scientifiques étaient rares. Message principal Les médecins de soins primaires sont couramment appelés à prendre en charge des patients victimes de blessures traumatiques à la main. Dans le contexte d’un cas clinique, nous examinons l’évaluation, le diagnostic et la prise en charge initiale des traumatismes communs à la main. La présentation et la prise en charge des blessures au lit de l’ongle, des amputations de l’extrémité du doigt, des doigts en maillet, des fractures à la main, des lacérations de tendons, des morsures et de la ténosynovite infectieuse seront aussi discutées. Les principes de la prise en charge des blessures traumatiques à la main comportent la réduction et l’immobilisation des fractures, la prescription d’imagerie radiographique post-réduction, l’obtention d’un recouvrement par les tissus mous, la prévention et le traitement des infections et l’assurance d’une prophylaxie antitétanique. Conclusion Il est essentiel d’assurer une évaluation et une prise en charge appropriées des blessures traumatiques à la main pour prévenir une morbidité considérable à long terme dans une population autrement en santé. La reconnaissance sans délai des blessures qui nécessitent une demande de consultation urgente ou rapide auprès d’un chirurgien spécialiste de la main est également critique.

  7. Connecticut observation wells; guidelines for network modification

    USGS Publications Warehouse

    Melvin, R.L.

    1986-01-01

    The U.S. Geological Survey and Connecticut Department of Environmental Protection are developing a baseline observation well network to assess the present status of groundwater storage and relate it to long-term conditions and to describe and characterize natural changes in groundwater storage in relation to climatic variations, topography, and hydrogeologic setting. An evaluation of the present network of 31 observation wells indicates it is not representative of climatic areas or major hydrologic units in the State. Several wells provide equivalent information and six can be discontinued. Network modifications, including deletion of some existing wells and the addition of 50 to 60 new observation wells are needed to meet network objectives. Fourteen existing wells that have long-term records should be retained as a basis for historical comparisons. (USGS)

  8. Modification of single Na+ channels by batrachotoxin.

    PubMed Central

    Quandt, F N; Narahashi, T

    1982-01-01

    The modifications in the properties of voltage-gated Na+ channels caused by batrachotoxin were studied by using the patch clamp method for measuring single channel currents from excised membranes of N1E-115 neuroblastoma cells. The toxin-modified open state of the Na+ channel has a decreased conductance in comparison to that of normal Na+ channels. The lifetime of the modified open state is drastically prolonged, and channels now continue to open during a maintained depolarization so that the probability of a channel being open becomes constant. Modified and normal open states of Na+ channels coexist in batrachotoxin-exposed membrane patches. Unlike the normal condition, Na+ channels exposed to batrachotoxin open spontaneously at large negative potentials. These spontaneous openings apparently cause the toxin-induced increase in Na+ permeability which, in turn, causes membrane depolarization. PMID:6292915

  9. Modifications to the silver physical developer.

    PubMed

    Burow, David; Seifert, Donald; Cantu, Antonio A

    2003-09-01

    The silver physical developer is currently the most successful reagent used for visualizing the water-insoluble components (e.g., lipids) of latent prints on porous surfaces. It is normally used after the amino acid visualizing reagents (e.g., ninhydrin and DFO) are used. This work found that the performance of the current formulation of silver physical developer is strongly reduced when the water used is changed from the usual distilled water to the more purified reverse osmosis/deionized (RO/DI) water. Based on numerous experiments involving the systematic variation of the component concentrations, the performance was restored and even improved by reducing the concentration of all the components (except that of the ferric salt) and by including malic acid in the formulation. These modifications resulted in a new silver physical developer formulation that performs as well as or better than the current formulation and is less expensive to make.

  10. Covalent modification of DNA regulates memory formation.

    PubMed

    Miller, Courtney A; Sweatt, J David

    2007-03-15

    DNA methylation is a covalent chemical modification of DNA catalyzed by DNA methyltransferases (DNMTs). DNA methylation is associated with transcriptional silencing and has been studied extensively as a lifelong molecular information storage mechanism put in place during development. Here we report that DNMT gene expression is upregulated in the adult rat hippocampus following contextual fear conditioning and that DNMT inhibition blocks memory formation. In addition, fear conditioning is associated with rapid methylation and transcriptional silencing of the memory suppressor gene PP1 and demethylation and transcriptional activation of the synaptic plasticity gene reelin, indicating both methyltransferase and demethylase activity during consolidation. DNMT inhibition prevents the PP1 methylation increase, resulting in aberrant transcription of the gene during the memory-consolidation period. These results demonstrate that DNA methylation is dynamically regulated in the adult nervous system and that this cellular mechanism is a crucial step in memory formation.

  11. Epigenetic Modifications of Major Depressive Disorder

    PubMed Central

    Saavedra, Kathleen; Molina-Márquez, Ana María; Saavedra, Nicolás; Zambrano, Tomás; Salazar, Luis A.

    2016-01-01

    Major depressive disorder (MDD) is a chronic disease whose neurological basis and pathophysiology remain poorly understood. Initially, it was proposed that genetic variations were responsible for the development of this disease. Nevertheless, several studies within the last decade have provided evidence suggesting that environmental factors play an important role in MDD pathophysiology. Alterations in epigenetics mechanism, such as DNA methylation, histone modification and microRNA expression could favor MDD advance in response to stressful experiences and environmental factors. The aim of this review is to describe genetic alterations, and particularly altered epigenetic mechanisms, that could be determinants for MDD progress, and how these alterations may arise as useful screening, diagnosis and treatment monitoring biomarkers of depressive disorders. PMID:27527165

  12. Polymer surface modification by plasmas and photons

    NASA Astrophysics Data System (ADS)

    Chan, C.-M.; Ko, T.-M.; Hiraoka, H.

    1996-05-01

    Polymers have been applied successfully in fields such as adhesion, biomaterials, protective coatings, friction and wear, composites, microelectronic devices, and thin-film technology. In general, special surface properties with regard to chemical composition, hydrophilicity, roughness, crystallinity, conductivity, lubricity, and cross-linking density are required for the success of these applications. Polymers very often do not possess the surface properties needed for these applications. However, they have excellent bulk physical and chemical properties, are inexpensive, and are easy to process. For these reasons, surface modification techniques which can transform these inexpensive materials into highly valuable finished products have become an important part of the plastics and many other industries. In recent years, many advances have been made in developing surface treatments to alter the chemical and physical properties of polymer surfaces without affecting bulk properties. Common surface modification techniques include treatments by flame, corona, plasmas, photons, electron beams, ion beams, X-rays, and γ-rays. Plasma treatment is probably the most versatile surface treatment technique. Different types of gases such as argon, oxygen, nitrogen, fluorine, carbon dioxide, and water can produce the unique surface properties required by various applications. For example, oxygen-plasma treatment can increase the surface energy of polymers, whereas fluorine-plasma treatment can decrease the surface energy and improve the chemical inertness. Cross-linking at a polymer surface can be introduced by an inert-gas plasma. Modification by plasma treatment is usually confined to the top several hundred ångströms and does not affect the bulk properties. The main disadvantage of this technique is that it requires a vacuum system, which increases the cost of operation. Thin polymer films with unique chemical and physical properties are produced by plasma polymerization

  13. Naturalness and the genetic modification of animals.

    PubMed

    Verhoog, Henk

    2003-07-01

    In the past few years it has been recognised that so-called intrinsic concerns about genetic modification (GM) of plants and animals, for food in particular, have an important role in the public perception of GM. One of these concerns is the view that GM is 'unnatural'. This article gives an overview of the often conflicting views on the argument of unnaturalness in books and reports. The author gives a new direction to this discussion, by contrasting the common sense view of nature and animals, with the scientific concept of nature and what is natural. The view of nature and what is natural is always normative. This is illustrated by making explicit the concept of nature in organic farming, which explains why GM is rejected.

  14. Analysis of oxidative modification of proteins.

    PubMed

    Yan, Liang-Jun

    2009-02-01

    Proteins are targets of oxidative modification. This unit describes detailed procedures for the analysis of popular indices of protein oxidation including protein carbonyl formation, loss of protein thiols, and nitrotyrosine and dityrosine formation, as well as isoaspartate formation. Procedures are detailed for the analysis of protein carbonyls labeled with 2,4-dinitrophenylhydrazine, tritiated sodium borohydride, and biotin-hydrazide, followed by detection measurements that are based on the distinguishing feature of each labeling chemical. Methods are outlined for the determination of protein cysteine oxidation by quantifying the loss of free protein thiols using radiolabeled [(14)C]-iodoacetamide. Protocols are described for the measurement of protein dityrosine by gas chromatography/mass spectrometry, as are the details for the detection of protein nitrotyrosine by a competitive ELISA approach. Finally, methods are described for the quantification of protein-bound isoaspartate using protein-L-isoaspartyl methyltransferase that converts aberrant L-isoaspartyl residues in peptides and proteins to normal aspartyl residues.

  15. Analysis of oxidative modification of proteins.

    PubMed

    Yan, Liang-Jun

    2009-04-01

    Proteins are targets of oxidative modification. This unit describes detailed procedures for the analysis of popular indices of protein oxidation including protein carbonyl formation, loss of protein thiols, and nitrotyrosine and dityrosine formation, as well as isoaspartate formation. Procedures are detailed for the analysis of protein carbonyls labeled with 2,4-dinitrophenylhydrazine, tritiated sodium borohydride, and biotin-hydrazide, followed by detection measurements that are based on the distinguishing feature of each labeling chemical. Methods are outlined for the determination of protein cysteine oxidation by quantifying the loss of free protein thiols using radiolabeled [(14)C]-iodoacetamide. Protocols are described for the measurement of protein dityrosine by gas chromatography/mass spectrometry, as are the details for the detection of protein nitrotyrosine by a competitive ELISA approach. Finally, methods are described for the quantification of protein-bound isoaspartate using protein-L-isoaspartyl methyltransferase that converts aberrant L-isoaspartyl residues in peptides and proteins to normal aspartyl residues.

  16. Lipid modification processes induced by thiyl radicals

    NASA Astrophysics Data System (ADS)

    Mihaljević, Branka; Bujak, Ivana Tartaro

    2016-07-01

    Polyunsaturated fatty acid (PUFA) oxidation by thiyl radicals (RS•) is believed to be responsible for some of the biological radiation damage. At the same time, RS• can cause isomerization of PUFA double bonds with the formation of trans isomers. The aim of this study was to better understand the competition between lipid peroxidation and geometrical isomerization processes in biomimetic model system of linoleic acid in the presence of 2-mercaptoethanol using irradiation as a method for free radicals generation. In air-equilibrated conditions the propagation of lipid peroxidation was dominant up to the dose of 400 Gy, after which at higher doses up to 10 kGy the termination occurred with the predominance of geometrical isomerization. This study revealed that undesirable and permanent lipid modifications are possible at higher irradiation doses which should be considered in the planning of irradiation treatment of foods and feeds with high content of lipids and sulfur compounds.

  17. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  18. Selective Surface Modification on Lubricant Retention

    NASA Astrophysics Data System (ADS)

    Jiang, Yu; Suvanto, Mika; Pakkanen, Tapani A.

    2016-11-01

    While surface patterns are effective in improving tribological properties, nevertheless they alter the surface wettability, which will in turn affect the surface-lubricant interactions. When there is a shortage of lubricant on a patterned surface, the lubricant stored inside the cavities will be extracted to compensate the surface lubricant dissipation. Additionally, the lubricant retention effect provided by the cavities is competing with the release of the lubricant. With weak surface-lubricant interaction, the retention is limited. Therefore, the lubrication will have a sudden failure, giving a dramatic transition to abrasive wear. To improve the performance of polar lubricants on hydrophobic polymer surfaces, both topographical and selective surface modifications were incorporated on injection molded polypropylene surfaces. Distinctive lubrication improvement was observed when the surface structure density for the lubricant storage was high, and the release of the lubricant was controlled by the interaction with the selectively modified surfaces.

  19. Shining light on modifications of gravity

    SciTech Connect

    Brax, Philippe; Burrage, Clare; Davis, Anne-Christine E-mail: Clare.Burrage@nottingham.ac.uk

    2012-10-01

    Many modifications of gravity introduce new scalar degrees of freedom, and in such theories matter fields typically couple to an effective metric that depends on both the true metric of spacetime and on the scalar field and its derivatives. Scalar field contributions to the effective metric can be classified as conformal and disformal. Disformal terms introduce gradient couplings between scalar fields and the energy momentum tensor of other matter fields, and cannot be constrained by fifth force experiments because the effects of these terms are trivial around static non-relativistic sources. The use of high-precision, low-energy photon experiments to search for conformally coupled scalar fields, called axion-like particles, is well known. In this article we show that these experiments are also constraining for disformal scalar field theories, and are particularly important because of the difficulty of constraining these couplings with other laboratory experiments.

  20. Posttranslational Protein Modifications in Plant Metabolism1

    PubMed Central

    Friso, Giulia; van Wijk, Klaas J.

    2015-01-01

    Posttranslational modifications (PTMs) of proteins greatly expand proteome diversity, increase functionality, and allow for rapid responses, all at relatively low costs for the cell. PTMs play key roles in plants through their impact on signaling, gene expression, protein stability and interactions, and enzyme kinetics. Following a brief discussion of the experimental and bioinformatics challenges of PTM identification, localization, and quantification (occupancy), a concise overview is provided of the major PTMs and their (potential) functional consequences in plants, with emphasis on plant metabolism. Classic examples that illustrate the regulation of plant metabolic enzymes and pathways by PTMs and their cross talk are summarized. Recent large-scale proteomics studies mapped many PTMs to a wide range of metabolic functions. Unraveling of the PTM code, i.e. a predictive understanding of the (combinatorial) consequences of PTMs, is needed to convert this growing wealth of data into an understanding of plant metabolic regulation. PMID:26338952

  1. Pursuing DNA catalysts for protein modification.

    PubMed

    Silverman, Scott K

    2015-05-19

    Catalysis is a fundamental chemical concept, and many kinds of catalysts have considerable practical value. Developing entirely new catalysts is an exciting challenge. Rational design and screening have provided many new small-molecule catalysts, and directed evolution has been used to optimize or redefine the function of many protein enzymes. However, these approaches have inherent limitations that prompt the pursuit of different kinds of catalysts using other experimental methods. Nature evolved RNA enzymes, or ribozymes, for key catalytic roles that in modern biology are limited to phosphodiester cleavage/ligation and amide bond formation. Artificial DNA enzymes, or deoxyribozymes, have great promise for a broad range of catalytic activities. They can be identified from unbiased (random) sequence populations as long as the appropriate in vitro selection strategies can be implemented for their identification. Notably, in vitro selection is different in key conceptual and practical ways from rational design, screening, and directed evolution. This Account describes the development by in vitro selection of DNA catalysts for many different kinds of covalent modification reactions of peptide and protein substrates, inspired in part by our earlier work with DNA-catalyzed RNA ligation reactions. In one set of studies, we have sought DNA-catalyzed peptide backbone cleavage, with the long-term goal of artificial DNA-based proteases. We originally anticipated that amide hydrolysis should be readily achieved, but in vitro selection instead surprisingly led to deoxyribozymes for DNA phosphodiester hydrolysis; this was unexpected because uncatalyzed amide bond hydrolysis is 10(5)-fold faster. After developing a suitable selection approach that actively avoids DNA hydrolysis, we were able to identify deoxyribozymes for hydrolysis of esters and aromatic amides (anilides). Aliphatic amide cleavage remains an ongoing focus, including via inclusion of chemically modified DNA

  2. Pursuing DNA Catalysts for Protein Modification

    PubMed Central

    Silverman, Scott K.

    2015-01-01

    Conspectus Catalysis is a fundamental chemical concept, and many kinds of catalysts have considerable practical value. Developing entirely new catalysts is an exciting challenge. Rational design and screening has provided many new small-molecule catalysts, and directed evolution has been used to optimize or redefine the function of many protein enzymes. However, these approaches have inherent limitations that prompt the pursuit of different kinds of catalysts using other experimental methods. Nature evolved RNA enzymes, or ribozymes, for key catalytic roles that in modern biology are limited to phosphodiester cleavage/ligation and amide bond formation. Artificial DNA enzymes, or deoxyribozymes, have great promise for a broad range of catalytic activities. They can be identified from unbiased (random) sequence populations, as long as the appropriate in vitro selection strategies can be implemented for their identification. Notably, in vitro selection is different in key conceptual and practical ways from rational design, screening, and directed evolution. This Account describes the development by in vitro selection of DNA catalysts for many different kinds of covalent modification reactions of peptide and protein substrates, inspired in part by our earlier work with DNA-catalyzed RNA ligation reactions. In one set of studies, we have sought DNA-catalyzed peptide backbone cleavage, with the long-term goal of artificial DNA-based proteases. We originally anticipated that amide hydrolysis should be readily achieved, but in vitro selection instead led surprisingly to deoxyribozymes for DNA phosphodiester hydrolysis; this was unexpected because uncatalyzed amide bond hydrolysis is 105-fold faster. After developing a suitable selection approach that actively avoids DNA hydrolysis, deoxyribozymes were identified for hydrolysis of esters and aromatic amides (anilides). Aliphatic amide cleavage remains an ongoing focus, including via inclusion in the catalyst of chemically

  3. Epigenetic Modifications of Major Depressive Disorder.

    PubMed

    Saavedra, Kathleen; Molina-Márquez, Ana María; Saavedra, Nicolás; Zambrano, Tomás; Salazar, Luis A

    2016-08-05

    Major depressive disorder (MDD) is a chronic disease whose neurological basis and pathophysiology remain poorly understood. Initially, it was proposed that genetic variations were responsible for the development of this disease. Nevertheless, several studies within the last decade have provided evidence suggesting that environmental factors play an important role in MDD pathophysiology. Alterations in epigenetics mechanism, such as DNA methylation, histone modification and microRNA expression could favor MDD advance in response to stressful experiences and environmental factors. The aim of this review is to describe genetic alterations, and particularly altered epigenetic mechanisms, that could be determinants for MDD progress, and how these alterations may arise as useful screening, diagnosis and treatment monitoring biomarkers of depressive disorders.

  4. Combined surface modification of commercial aluminum

    NASA Astrophysics Data System (ADS)

    Ivanov, Yu; Lopatin, I.; Akhmadeev, Yu; Petrikova, E.; Teresov, A.; Shugurov, V.; Tolkachev, O.; Koval, N.

    2017-01-01

    The paper analyzes research data on the structure and properties of surface layers of commercially pure A7-grade aluminum subjected to treatment that combines deposition of a thin metal film, intense pulsed electron beam irradiation, and nitriding in low-pressure arc plasma. The analysis shows that the combined method of surface modification provides the formation of a multilayer structure with submicro- and nano-sized phases in the material through a depth of up to 40 μm, allowing a manifold increase in its surface microhardness and wear resistance (up to 4 and 9 times, respectively) compared to the material core. The main factors responsible for the high surface strength are the saturation of the aluminum lattice with nitrogen atoms and the formation of nano-sized particles of aluminum nitride and iron aluminides.

  5. Modifications to installed Sphincter design gloveports

    SciTech Connect

    Shetty, S.S.; Gilkison, J.M.

    1993-02-01

    This paper presents the results of a study of alternative methods for replacing Sphincter designed gloveports in gloveboxes. In addition, the paper discusses modifications that are required on metal glovebox wall panels to allow replacement of the Sphincter gloveports. A review of Westinghouse Savannah River Co. (WSRC) maintenance records showed that gloveports manufactured by Central Research, Incorporated, provide the lowest risk for failure. This assessment is based on the records of glove-to-port seal life and air in-leakage. These records also indicate the glove changes are made in shorter times with fewer workers than required by alternate gloveport designs studied. These attributes culminate in a significant decrease in radiation exposure and assimilation risk of maintenance personnel replacing gloves. Further, the Central Research design reduces the number of expandable hardware parts required to achieve a glove replacement. This reduction in expendable materials can result in a significant reduction in contaminated waste volume generated during a glove replacement.

  6. Genome modification by CRISPR/Cas9.

    PubMed

    Ma, Yuanwu; Zhang, Lianfeng; Huang, Xingxu

    2014-12-01

    Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas)9-mediated genome modification enables us to edit the genomes of a variety of organisms rapidly and efficiently. The advantages of the CRISPR-Cas9 system have made it an increasingly popular genetic engineering tool for biological and therapeutic applications. Moreover, CRISPR-Cas9 has been employed to recruit functional domains that repress/activate gene expression or label specific genomic loci in living cells or organisms, in order to explore developmental mechanisms, gene expression regulation, and animal behavior. One major concern about this system is its specificity; although CRISPR-Cas9-mediated off-target mutation has been broadly studied, more efforts are required to further improve the specificity of CRISPR-Cas9. We will also discuss the potential applications of CRISPR-Cas9.

  7. Mitochondrial Modification Techniques and Ethical Issues.

    PubMed

    Gómez-Tatay, Lucía; Hernández-Andreu, José M; Aznar, Justo

    2017-02-24

    Current strategies for preventing the transmission of mitochondrial disease to offspring include techniques known as mitochondrial replacement and mitochondrial gene editing. This technology has already been applied in humans on several occasions, and the first baby with donor mitochondria has already been born. However, these techniques raise several ethical concerns, among which is the fact that they entail genetic modification of the germline, as well as presenting safety problems in relation to a possible mismatch between the nuclear and mitochondrial DNA, maternal mitochondrial DNA carryover, and the "reversion" phenomenon. In this essay, we discuss these questions, highlighting the advantages of some techniques over others from an ethical point of view, and we conclude that none of these are ready to be safely applied in humans.

  8. A ``fractal'' modification of Torricelli's formula

    NASA Astrophysics Data System (ADS)

    Maramathas, Athanasios J.; Boudouvis, Andreas G.

    2010-03-01

    A modification is proposed of Torricelli’s (1608-1647) formula for the velocity of water discharging from a small hole at the bottom of a large tank filled with fractal solid material. The new formula takes proper account of the mechanical energy losses due to flow in the solid matrix, thus expanding the area of validity of the classical Torricelli’s formula. Moreover, it offers a convenient alternative to Darcy’s law for estimating the discharge rate from an aquifer. The new formula was derived from laboratory experiments, with a low-Reynolds number discharge flow (Darcian flow). It was tested in a natural karst aquifer where the flow is non-Darcian, at Almiros spring on the island of Crete (Greece). In both cases, the predictive capability of the modified formula is established.

  9. Ion beam and laser induced surface modifications

    NASA Astrophysics Data System (ADS)

    Appleton, B. R.

    1984-01-01

    The capabilities of energetic ion beam and laser processing of surfaces are reviewed. Ion implantation doping, ion beam mixing, and laser and electron beam processing techniques are capable of producing new and often unique surface properties. The inherent control of these techniques has led to significant advances in our ability to tailor the properties of solids for a wide range of technological applications. Equally important, these techniques have allowed tests of fundamental materials interactions under conditions not heretofore achievable and have resulted in increased understanding of a broad range of materials phenomena. These include new metastable phase formation, rapid nucleation and crystal growth kinetics, amorphous metals and metaglasses, supersaturated solid solutions and substitutional alloys, interface interactions, solute trapping, laser-assisted chemical modifications, and a host of other.

  10. Cryochemical modification, activity, and toxicity of dioxidine

    NASA Astrophysics Data System (ADS)

    Vernaya, O. I.; Shabatin, V. P.; Shabatina, T. I.; Khvatov, D. I.; Semenov, A. M.; Yudina, T. P.; Danilov, V. S.

    2017-02-01

    Dioxidine nanoparticles are prepared via cryochemical modification of the pharmacopoeial dioxidine substance. The form of the cryomodified dioxidine is characterized by data from 1H NMR spectroscopy; X-ray diffraction analysis; such thermal analytical methods as TG and DSC; low-temperature argon adsorption; and transmission electron microscopy. It is shown that the cryomodified samples are synthesized in the form of dioxidine nanocrystals 50-300 nm in size, with a crystal structure differing from that of the initial pharmacopoeial substance. The prepared cryomodified dioxidine nanoparticles inhibit the growth of E. coli 52, S. aureus 144, M. cyaneum 98, and B. cereus 9 better than the initial pharmacopoeial substance, and have comparable chronic toxicity.

  11. Gold Nanowires and Their Chemical Modifications

    NASA Astrophysics Data System (ADS)

    Häkkinen, Hannu; Barnett, Robert N.; Landman, Uzi

    2000-03-01

    Atomic structure, electronic structure, and ballistic transport in thin gold nanowires at their final stages before break-up, recently imaged by high-resolution electron microscopy,(H. Ohnishi et al., Nature 395), 780 (1998) are investigated with density functional simulations.(H. Häkkinen et al., J. Phys. Chem. B 103), 8814 (1999) We discuss stretching mechanisms leading to elongated chain-like structures showing dimerization akin to a Peierls transition and retaining conductance close to unity for stretching lengths that exceed considerably a typical interatomic bond length. We also demonstrate a chemical modification of the wire via adsorption of a methyl thiol molecule and discuss its effects on the structure and conductance.

  12. Cell Signalling Through Covalent Modification and Allostery

    NASA Astrophysics Data System (ADS)

    Johnson, Louise N.

    Phosphorylation plays essential roles in nearly every aspect of cell life. Protein kinases catalyze the transfer of the γ-phosphate of ATP to a serine, threonine or tyrosine residue in protein substrates. This covalent modification allows activation or inhibition of enzyme activity, creates recognition sites for other proteins and promotes order/disorder or disorder/order transitions. These properties regulate ­signalling pathways and cellular processes that mediate metabolism, transcription, cell cycle progression, differentiation, cytoskeleton arrangement and cell movement, apoptosis, intercellular communication, and neuronal and immunological functions. In this lecture I shall review the structural consequences of protein phosphorylation using our work on glycogen phosphorylase and the cell cycle cyclin dependent protein kinases as illustrations. Regulation of protein phosphorylation may be disrupted in the diseased state and protein kinases have become high profile targets for drug development. To date there are 11 compounds that have been approved for clinical use in the treatment of cancer.

  13. A study of microbial profile modification

    SciTech Connect

    Bae, J.H.; Lee, H.O.

    1995-12-31

    A microbial profile modification method using spores was investigated. A halotolerant, spore-forming, biopolymer-producing mesophile was used in Berea cores with a specifically formulated nutrient package to reduce the permeability of the rock. The degree of permeability reduction varied widely depending on the stimulation protocols used. The incubation period had a significant impact on permeability reduction, and there appeared to be an optimum incubation time for maximum permeability reduction. The reduction persisted for many PV of brine injection and appeared very stable. For our microbes used in this study, the permeability reduction was about the same when the NaCl concentration was above 2 wt% in the range from 0 wt% to 10 wt%.

  14. Nanoindentation for surface modification of nanofilms

    NASA Astrophysics Data System (ADS)

    Luchenko, A. I.; Melnichenko, M. M.

    2015-08-01

    In the work it is shown practical use of a scanning tunneling microscope for indentation in the continuous micro- and nano-range. A maximum load of 2.64 cN (and 0.4 cN minimum) was applied on a piezo-scanner to achieve the indentation. The relaxation changes of modified surface by contact method was investigated. It is shown that within a few hours of modification there is clear evidence of inevitable loss of information about the morphology of initially modified area. The possibility of modifying the sample surface by tunneling current was shown. This may enable preparation of the surface for subsequent applications in which it is necessary to reduce the average irregularities of the surface. Nano-objects on the surface of the experimental samples were created by using the developed method.

  15. Mitochondrial Modification Techniques and Ethical Issues

    PubMed Central

    Gómez-Tatay, Lucía; Hernández-Andreu, José M.; Aznar, Justo

    2017-01-01

    Current strategies for preventing the transmission of mitochondrial disease to offspring include techniques known as mitochondrial replacement and mitochondrial gene editing. This technology has already been applied in humans on several occasions, and the first baby with donor mitochondria has already been born. However, these techniques raise several ethical concerns, among which is the fact that they entail genetic modification of the germline, as well as presenting safety problems in relation to a possible mismatch between the nuclear and mitochondrial DNA, maternal mitochondrial DNA carryover, and the “reversion” phenomenon. In this essay, we discuss these questions, highlighting the advantages of some techniques over others from an ethical point of view, and we conclude that none of these are ready to be safely applied in humans. PMID:28245555

  16. On the genetic modification of psychology, personality, and behavior.

    PubMed

    Neitzke, Alex B

    2012-12-01

    I argue that the use of heritable modifications for psychology, personality, and behavior should be limited to the reversal or prevention of relatively unambiguous instances of pathology or likely harm (e.g. sociopathy). Most of the likely modifications of psychological personality would not be of this nature, however, and parents therefore should not have the freedom to make such modifications to future children. I argue by examining the viewpoints of both the individual and society. For individuals, modifications would interfere with their capacity for self-determination in a way that undermines the very concept of self-determination. I argue that modification of psychology and personality is unlike present parenting in morally significant ways. For society, modification offers a medium for power to manipulate the makeup of persons and populations, possibly causing biological harm to the species and altering our conceptions of social responsibility.

  17. Monopoles and Modifications of Bundles over Elliptic Curves

    NASA Astrophysics Data System (ADS)

    Levin, Andrey M.; Olshanetsky, Mikhail A.; Zotov, Andrei V.

    2009-06-01

    Modifications of bundles over complex curves is an operation that allows one to construct a new bundle from a given one. Modifications can change a topological type of bundle. We describe the topological type in terms of the characteristic classes of the bundle. Being applied to the Higgs bundles modifications establish an equivalence between different classical integrable systems. Following Kapustin and Witten we define the modifications in terms of monopole solutions of the Bogomolny equation. We find the Dirac monopole solution in the case R × (elliptic curve). This solution is a three-dimensional generalization of the Kronecker series. We give two representations for this solution and derive a functional equation for it generalizing the Kronecker results. We use it to define Abelian modifications for bundles of arbitrary rank. We also describe non-Abelian modifications in terms of theta-functions with characteristic.

  18. Profile modification to minimize spur gear dynamic loading

    NASA Technical Reports Server (NTRS)

    Lin, H. H.; Townsend, D. P.; Oswald, F. B.

    1989-01-01

    An analytical computer simulation program for dynamic modeling of low-contact-ratio spur gear systems is presented. The procedure computes the static transmission error of the gears operating under load and uses a fast Fourier transform to generate the frequency spectrum of the static transmission error at various tooth profile modifications. The dynamic loading response of an unmodified (perfect involute) gear pair was compared with that of gears with various profile modifications. Correlations were found between various profile modifications and the resulting dynamic loads. An effective error, obtained from frequency domain analysis of the static transmission error of the gears, gave a very good indication of the optimum profile modification to reduce gear dynamic loading. Design curves generated by dynamic simulation at various profile modifications are given for gear systems operated at various loads. Optimum profile modifications can be determined from these design curves for improved gear design.

  19. Profile modification to minimize spur gear dynamic loading

    NASA Technical Reports Server (NTRS)

    Lin, Hsiang Hsi; Townsend, Dennis P.; Oswald, Fred B.

    1987-01-01

    An analytical computer simulation program for dynamic modeling of low-contact-ratio spur gear systems is presented. The procedure computes the static transmission error of the gears operating under load and uses a fast Fourier transform to generate the frequency spectrum of the static transmission error at various tooth profile modifications. The dynamic loading response of an unmodified (perfect involute) gear pair was compared with that of gears with various profile modifications. Correlations were found between various profile modifications and the resulting dynamic loads. An effective error, obtained from frequency domain analysis of the static transmission error of the gears, gave a very good indication of the optimum profile modification to reduce gear dynamic loading. Design curves generated by dynamic simulation at various profile modifications are given for gear systems operated at various loads. Optimum profile modifications can be determined from these design curves for improved gear design.

  20. Muscle modifications in Parkinson's disease: myoelectric manifestations.

    PubMed

    Rossi, B; Siciliano, G; Carboncini, M C; Manca, M L; Massetani, R; Viacava, P; Muratorio, A

    1996-06-01

    The muscle changes occurring in Parkinson's disease (PD) may come about as a consequence of the modified pattern of motor unit activation and rigidity, which are characteristic of the disease. A tendency towards hypertrophy of type I fibers and, in some instances, atrophy of type II fibers has been observed. Fourteen patients affected by PD and 10 age-matched controls were studied in order to investigate these muscle changes. We indirectly evaluated muscle modifications by measuring muscle fiber conduction velocity (CV) and median frequency (MDF) of the power spectrum using automatic analysis of surface EMG. The tibialis anterior muscle was selected for the study of contractions electrically induced by 35 Hz pulse trains lasting 30 s; the myoelectric signal was detected using the 4-bar electrode technique described by Broman et al. (Broman, H., Bilotto, G. and De Luca, C.J. Myoelectric signal conduction velocity and spectral parameters: influence of force and time. J. Appl. Physiol., 1985, 58: 1428-1437). Muscle biopsy specimens were obtained in 4 PD patients by surgical excision at the site where the EMG recording electrode had been placed. The main difference observed between PD subjects and controls was the rate of change of MDF and CV during the course of stimulated contraction; patients with PD sustained a smaller fatigue related decrease in both parameters compared to controls. According to our histological data, this result can be explained by a type I fiber percentage which accounts for 79% of the myofiber population on average. As expected, the CV basal values correlated directly with type I fiber diameter. These data suggest that non-invasive surface EMG techniques are useful in assessing the modifications of muscle characteristics that are observed in PD patients and for analyzing some aspects of the peripheral fatigue in this disease.