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Sample records for comportement experimental statique

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

    NASA Astrophysics Data System (ADS)

    Bouguerra, Kheireddine

    'assemblage inferieur, (3) la resistance en compression du beton, et (4) le taux d'armature dans les autres directions (armatures transversale et longitudinale de l'assemblage superieur et l'armature longitudinale de l'assemblage inferieur). Lors des essais de chargement, les dalles ont ete supportees par deux poutrelles metalliques espacees de 2000 mm centre a centre et soumises a une charge statique concentree sur une aire de contact de 600 mm x 250 mm afin de simuler une charge de camion (87,5 kN--CL-625) et ce conformement au code Canadien sur le calcul des ponts routiers [CAN/CSA-S6-06]. Aussi, une analyse numerique du comportement des dalles testees sous charges est faite a l'aide d'un logiciel d'elements finis ADINA version 8.2. Les essais ont montre que toutes les dalles testees ont rompu par poinconnement, peu importe le parametre etudie. Aussi, une epaisseur de dalle de 175 mm repond aux exigences du Canadien sur le calcul des ponts routiers [CAN/CSA-S6-06]. Par ailleurs, les resultats ont montre que la resistance en compression du beton est un parametre qui influe sur la deflexion, les deformations dans les barres et l'ouverture de fissures. Enfin, les resultats des analyses numeriques effectuees corroborent avec ceux obtenus experimentalement. Mots cles. Dalle de ponts en beton, armature de PRF, charges statiques, flexion, deformations, poinconnement, elements finis.

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

    NASA Astrophysics Data System (ADS)

    Metiche, Slimane

    entre ces proprietes est due au nombre de couches utilisees dans chaque zone ainsi qu'a l'orientation des fibres de chaque couche. Un total de vingt-trois prototypes de dimensions differentes; ont ete testes en flexion jusqu'a la rupture. Deux types de fibres de verre de masses lineaires differentes, ont ete utilisees afin d'evaluer l'effet du type de fibres sur le comportement a la flexion. Un nouveau montage experimental permettant de tester tous les types de poteaux en PRF a ete dimensionne et fabrique selon les recommandations decrites dans les normes ASTM D 4923-01 et ANSI C 136.20-2005. Un modele analytique base sur la theorie des poutres en elasticite lineaire est propose dans cette these. Ce modele predit avec une bonne precision le comportement experimental charge---deflexion ainsi que la deflexion maximale au sommet des poteaux en PRF; constitues de plusieurs zones de caracteristiques geometriques et mecaniques differentes. Une procedure de dimensionnement des poteaux en PRF, basee sur les resultats experimentaux obtenus dans le cadre de la presente these, est egalement proposee. Les resultats obtenus dans le cadre de la presente these permettront le developpement et l'amelioration des regles de conception utiles et pratiques a l'usage des concepteurs et des industriels du domaine des poteaux en PRF. Les retombees de cette recherche sont a la fois economiques et technologiques, car les resultats obtenus constitueront une banque de donnees qui contribueront au developpement des normes de calcul, et par consequent a l'optimisation des materiaux utilises, et serviront a valider de futurs resultats et modeles theoriques.

  3. The viewing room: A lens for developing ethical comportment.

    PubMed

    McAllister, Margaret; Levett-Jones, Tracy; Petrini, Marcia A; Lasater, Kathie

    2016-01-01

    Healthcare is dynamic and complex, and against this background, nursing students must negotiate the transition from lay person to healthcare professional. Diverse life experiences and learning styles can further complicate this journey of transformation. The contemporary role of the nurse includes caring for and making clinical decisions about patients based on ethical principles. Learning about and integrating ethical comportment as part of the transformative journey requires nurse educators to create and implement learning experiences that challenge nursing students to think deeply and broadly about the experiences they encounter, to question their previous assumptions and prejudices, to consider the world of healthcare through a new lens, and to reflect on and learn from the process. The judicious use of film has the potential to assist students to recognize and develop ethical comportment as they prepare for real-world clinical practice experiences. In this paper, we present three film exemplars and related teaching strategies designed to facilitate transformative learning and development of ethical comportment.

  4. Etude du comportement et de la modélisation viscoplastique du zircaloy 4recristallisé sous chargements monotones et cycliques uni et multiaxes

    NASA Astrophysics Data System (ADS)

    Delobelle, P.; Robinet, P.

    1994-08-01

    à la température ambiante ainsi que l'indépendance du rapport R^p = \\varepsilon^p_{θθ}/\\varepsilon^ p_{{^-_-}{^-_-} } avec la température laissent supposer que l'ensemble des coefficients d'anisotropie ne dépendent pas de la température. Par contre, la fluidité de cet alliage présente un minimum très marqué au voisinage de 300 ^{circ}C. Ce comportement est imputable au vieillissement dynamique fréquemment observé dans les solutions solides d'insertion. Lors d'un chargement cyclique hors phase (traction-torsion déphasée à 90^{circ}) ce matériau présente un léger durcissement supplémentaire. On propose l'extension au cas du zircaloy 4 de la formulation d'un modèle viscoplastique unifié développé et identifié par ailleurs sur d'autres matériaux initialement isotropes. D'une manière générale, l'introduction de l'anisotropie dans ce modèle s'effectue par l'intermédiaire de quatre tenseurs d'ordre 4 affectant les directions d'écoulement [ M] , les parties linéaires des écrouissages cinématiques [ N] , ainsi que les restaurations dynamiques [ Q] et statiques [ R] de ces mêmes variables d'écrouissage. L'identification de ce modèle est discutée et réalisée à 350 ^{circ}C. On montre l'adéquation du formalisme à appréhender l'ensemble des caractéristiques mécaniques de cet alliage.

  5. Étude expérimentale et modélisation du comportement en compression des structures nid d'abeille

    NASA Astrophysics Data System (ADS)

    Aminanda, Y.; Castanié, B.; Barrau, J. J.; Thévenet, P.; Guedra-Degeorges, D.

    2002-12-01

    Dans le domaine aéronautique les impacts, même de faible énergie, sur des structures sandwichs à âme nid d'abeille posent des problèmes majeurs en terme de résistance résiduelle. La modélisation de l'endom magement dû à l'impact nécessite la connaissance préliminaire du comportement du nid d'abeille en compression. Des essais réalisés en compression quasi-statique uniforme sur des pains de nids d'abeille en différents matériaux (Nomex, Aluminium et Canson) permettent de décomposer la séquence de formation du pli et les facteurs influents. Ces essais tendent à montrer que la force de compression transite essentiellement par les arêtes verticales du nida. Des essais complémentaires sur un motif d'arête confirme cette analyse. La modélisation issue de cette analyse propose, pour connaître la réponse d'une structure nid d'abeille en compression ou indentation, de déterminer la réponse individuelle d'une arête verticale par un essai de compression uniforme. A partir de la loi expérimentale obtenue, la réponse à l'indentation de la structure sandwich est la superposition de la réponse des arêtes pour la forme d'indenteur et la profondeur d'indentation considérée. Une bonne corrélation essais/calcul est obtenue lors d'essais de validation sur nida Nomex avec diverses formes d'indenteurs. La méthode proposée est générale et peut être étendue à divers matériaux cellulaires.

  6. Etude des proprietes mecaniques statiques et dynamiques de pieces d'acier elaborees par metallurgie des poudres

    NASA Astrophysics Data System (ADS)

    Bernier, Fabrice

    The main objective of this thesis ais to gain a better understanding of the effects of processing variables on the porosity and microstructure of powder metallurgy (P/M) steel and their effect on mechanical properties, both static and dynamic. The effects of processing variables on porosity and microstructure were evaluated by advanced microstructural characterization using both optical and electron microscopies. Then the impacts of porosity and microstructure on both static and dynamic properties were measured. Static mechanical properties were characterized by hardness measurements and by tensile tests while fatigue testing was used for evaluating dynamic properties. Fractographic observations were made on tensile and fatigue fracture samples to correlate the microstructural features to the mechanical performance of P/M steels. The experimental work covered in this Ph.D. thesis enables to further understand the mechanisms by which process variables affect the microstructure and the mechanical properties of samples. In the first paper, the effect of prealloying MnS up to 1.0 wt pct on the microstructural features of non-metallic inclusions and their impact on tensile and fatigue properties of a 7.0 g/cm3 P/M steel (Fe-2.0Cu-0.7C) have been investigated. As the MnS content increases, larger, more irregular and more closely spaced inclusions are obtained. Whilst no significant impact on both static and dynamic properties was observed when prealloying up to 0.65 wt pct MnS, a decrease of more than 15 pct of the ultimate tensile strength and of the endurance limit was found when the MnS content reaches 1.0 wt pct. The decrease in the ultimate tensile strength is attributed to a lower ductility of the sinternecks, as void initiation and void growth were promoted at lower stress levels by larger inclusions. The larger size of the MnS particles and the lower mean free path between non-metallic inclusions also favor microcrack initiation and their coalescence into cracks

  7. Comportement mecanique des joints boulonnes en composites verre-polyester

    NASA Astrophysics Data System (ADS)

    Vangrimde, Bart

    Glass fibre-reinforced polyester composite materials are being extensively used for general-purpose applications. For highly loaded structures, bolted joints are generally the preferred assembly method. However, bolted joints are usually the weakest link in a structure and they must therefore be designed with care. Specifically, the joint geometry, reinforcement type and lay-up should be chosen on a rational basis, otherwise the assembly may fail prematurely. The present study is concerned with the study of these material parameters. The mechanical response of bolted assemblies is studied for a range of six glass fibre-reinforced polyester laminates with reinforcements and lay-ups that are typical for general-purpose applications. In order to assess how changes in joint width or in joint end distance affect the behaviour of the joint, tests were carried out on three coupon geometries. In accordance with the standard test method ASTM D5961, a single-bolt double lap bolted joint configuration was used for the experimental characterisation. We investigated how the displacement measurement could best be made because currently there is a whole range of approaches in use and it is clear that the measured displacement quantity directly affects the stiffness values. A 3-D finite element model indicated that bolt deformation and fixture deformations affected the measured coupon displacement. The bearing stiffness was reduced by 26% on average when the width was reduced from six to two times the hole diameter. For the assemblies with a width of two times the hole diameter (w/D = 2) the bearing stiffness increased clearly with the tensile modulus of the tested materials. Both the experimental and numerical bearing stiffness values were much lower than those predicted by joint flexibility formulas. Hence, our results indicate that these joint flexibility formulas should be adapted if they are intended to be used for design of general-purpose glass fibre-reinforced polyester

  8. Comportement monotone et cyclique d'un sable limoneux

    NASA Astrophysics Data System (ADS)

    Arab, Ahmed

    2009-08-01

    This Note presents a laboratory study of the influence of low plastic fines on the behavior of a silty sand. The study is based on drained and undrained triaxial compression tests which were carried out for fractions of fines varying between 0 and 50%. Tests were conducted on samples a medium dense sand having a relative density I=0.5. The Note is composed of two parts. The first one presents the characteristics of the soils used in this study, the second provides an analysis of the experimental results and discusses the influence of fines on the mechanical characteristics of the sand-silt mixture. The tests show that the increase in the fines fraction reduces the soil dilatancy and amplifies the phase of contractance. It has a weak influence on the characteristic angle, but reduces the frictional angle of the soil. The third part presents the influence of relative density and fines content on the cyclic behavior and discusses their influence on the liquefaction potential of the sand-silt mixture. The tests show that the potential of liquefaction increase with increasing relative density and the resistance of liquefaction decrease with the increase of fines content. To cite this article: A. Arab, C. R. Mecanique 337 (2009).

  9. Analyse du comportement thermique du sol d'une serre agricole par simulation dynamique

    NASA Astrophysics Data System (ADS)

    Monteil, C.; Amouroux, M.

    1997-02-01

    The overall energetical behaviour of a greenhouse is significantly affected by diurnal storage and nocturnal release of energy inside the soil, which is the only element with high thermal capacitance. Its specific part is analysed with a pre-existing dynamic simulation model. The first part of this paper studies the effects of 4kinds of heating exchangers along each month of an entire cultivation period: hot air convector, aerial metallic pipes with hot water circulation, radiant mulch or buried pipes with warm water circulation. The second part develops the hourly behaviour of both greenhouse and soil during a cold standard-day with each of the 4exchangers. The third part is a sensibility study to various classes of factors in the case of hot air convector exchanger: climatic environment, control policy, intrinsic properties of the greenhouse (soil characteristics, crop density, cover transparency). Le comportement énergétique global d'une serre agricole est influencé de manière parfois importante par le stockage diurne et la restitution nocturne d'énergie au sein de son sol, seul élément à grande capacité thermique. Le rôle spécifique joué par le sol est analysé en appliquant un modèle de simulation dynamique déjà existant. Une première partie compare les effets de 4types d'échangeurs de chauffage sur chaque mois d'une période de culture : aérotherme, tubes aériens à circulation d'eau chaude, paillage radiant ou tubes enterrés à circulation d'eau tiède. Une seconde partie développe le comportement horaire de la serre et du sol pour une journée-type froide en présence de chacun des échangeurs. Une troisième partie précise la sensibilité du bilan thermique de la serre et du sol à différents types de facteurs dans le cas d'un échangeur par aérotherme: environnement climatique, politique de contrôle de la serre, propriétés intrinsèques de la serre (caractéristiques du sol, densité de culture, transparence de la couverture).

  10. 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

  11. Modelisation et simulation du comportement des alliages de magnesium lors de la deformation a chaud

    NASA Astrophysics Data System (ADS)

    Levesque, Julie

    Les alliages de magnesium sont de plus en plus utilises dans l'industrie automobile. Leur faible masse volumique permet d'alleger les vehicules, donc de diminuer l'utilisation de carburant et les emissions de gaz a effet de serre. La ductilite du magnesium a temperature ambiante est faible, mais une augmentation de celle-ci permet l'activation de systemes de glissement supplementaires et une meilleure formabilite. L'hydroformage a chaud pourrait donc permettre de fabriquer des pieces en alliages de magnesium destinees a l'industrie automobile. L'objectif de ce travail etait de developper un modele numerique permettant de simuler le comportement des alliages de magnesium deformes a temperature moderee (200°C). Les principales difficultes resident dans le fait que le magnesium ne se deforme pas seulement par glissement, mais aussi par maclage. En plus de reorienter les mailles cristallines, le maclage amene egalement un schema de durcissement complexe. Le modele utilise en est un de plasticite cristalline, qui tient compte de l'evolution de la texture lors de la deformation. Le modele de depart a ete adapte au magnesium en y incluant le maclage. Il tient compte de la reorientation des mailles cristallines, ainsi que du durcissement cause par les joints de macles. Le modele a d'abord ete calibre grace aux courbes de traction et de compression uniaxiale, puis a ete valide par la simulation de l'essai de deformation circonferentielle. L'evolution de texture observee a aussi permis de valider le modele. Des equations permettant d'ajuster les parametres du modele en fonction du taux de deformation ont egalement ete developpees. Les diagrammes des limites de formage dans les directions conventionnelle et d'hydroformage ont ete traces. Le maclage semble contribuer legerement a la formabilite des alliages de magnesium a la temperature etudiee. Une augmentation de l'index de sensibilite a la vitesse de deformation a aussi un effet positif sur la formabilite. Les resultats

  12. Étude du comportement structural de l'alliage NC 19 Fe Nb (Inconel 718)

    NASA Astrophysics Data System (ADS)

    Slama, C.; Cizeron, G.

    1997-03-01

    In the as-received state (following a double treatment at 720 and 620 °C), the structure of INC 718 consists of a γ matrix, intergranular β precipitates and (Nb,Ti)C carbides; moreover, γ{'} and γ{''} phases have precipitated in the matrix. Using different methods, the structural behaviour was analyzed which led to distinguish the temperature ranges in which occurs precipitation or dissolution of β, γ{'} and γ{''} phases on heating and to define the optimum conditions of homogeneization. Furthermore a CCT diagram for INC 718 has been drawn showing the respective precipitation of γ{'}, γ{''} and β phases as a function of the cooling rate applied from 990 °C. L'étude de l'alliage Inconel 718 (NC 19 Fe Nb) a permis de montrer que sa structure, dans l'état de livraison (après double revenu à 720 puis 620 °C), consiste en une matrice γ avec des précipités β intergranulaires et des carbures du type (Nb,Ti) C ; en outre, la matrice contient des précipités des phases γ{''} et γ{'}. L'analyse du comportement structural de l'alliage à l'aide de différentes méthodes physiques a conduit à délimiter les domaines de température dans lesquels interviennent, au chauffage, la précipitation ou la dissolution des phases β, γ{'}, γ{''} et de définir les conditions optimales d'homogénéisation. Le diagramme T.R.C. de l'Inconel 718 a ensuite été tracé : les intervalles de température dans lesquels interviennent les précipitations respectives des phases γ{'}, γ{''} et β en fonction de la vitesse de refroidissement imposée depuis 990 °C, ont ainsi pu être précisés.

  13. Ecole et Comportement: Session de formation ou de perfectionnement sur l'intervention au secondaire (School and Behavior: Preservice or Inservice Training on Intervention at the Secondary Level).

    ERIC Educational Resources Information Center

    Audet, Danielle; And Others

    A 2-day training session on interventions for use with secondary students who have behavior problems is presented. The first section is a participant's workbook, which contains 23 training activities. For each activity, the workbook indicates the relevant section of a companion guide "Ecole et Comportement: Un Guide d'Intervention au…

  14. Séchage statique des céréales à basse temperature. Utilisation detoitures solaires pour séchoir à maïs

    NASA Astrophysics Data System (ADS)

    Fournier, M.; Maurissen, Y.; Harouna, I.

    1994-03-01

    Low temperature grain drying is a good technic for agriculture. A mathematical model for a solarised silo has been chosen then experimentally validated. Drying sessions can be simulated to find parameter sensibility or optimal design for the dryer. The comparison criterion used, is the specific consumption, CS, the necessary energy to extract one kilo of water out of grain. The CS is always compared with traditional fuel dryer. According to working conditions, the drying may be economic, but it is necessary to control carefully the dryer. Le séchage du grain à basse température dans un silo de stockage, est une technique qui semble convenir aux agriculteurs de nombreux pays en particulier aux USA. Pour essayer de déterminer l'intérêt économique de la solarisation du silo, un modèle mathématique du séchoir à été choisi puis validé expérimentalement. Des opérations de séchage peuvent alors être simulées dans le but de déterminer soit la sensibilité des paramètres utilisés, soit le design optimal du silo. La consommation spécifique, CS, énergie nécessaire à l'extraction d'un kilo d'eau du grain, sert de critère de comparaison entre les séchoirs solaires et les séchoirs à fuel traditionnels. Suivant les conditions de fonctionnement, l'opération peut être plus ou moins rentable, donc la conduite de l'opération implique de bien maîtriser la conduite du séchage.

  15. Approche pour les comportements sexuels inappropriés chez des personnes atteintes de démence

    PubMed Central

    Joller, Petra; Gupta, Neeraj; Seitz, Dallas P.; Frank, Christopher; Gibson, Michelle; Gill, Sudeep S.

    2013-01-01

    Résumé Objectif Présenter aux médecins de famille une mise à jour sur l’approche au diagnostic et à la prise en charge des comportements sexuels inappropriés (CSI) chez les personnes atteintes de démence. Sources des données On a fait une recherche dans MEDLINE et EMBASE pour cerner des articles pertinents publiés avant juin 2012. On n’a trouvé aucune étude de niveau I; la plupart des articles fournissaient des données probantes de niveau III. Message principal Les comportements sexuels inappropriés sont fréquents chez les personnes atteintes de démence. Divers facteurs (p. ex., culturels, religieux, perspectives sociétales de la sexualité gériatrique, questions médicolégales) pourraient compliquer l’évaluation de tels comportements et doivent être pris en compte pour permettre une prise en charge appropriée à chaque patient. Il existe des outils pour documenter les CSI. Des interventions créatives non pharmacologiques pour les CSI pourraient être efficaces quand elles sont adaptées à chaque patient. Certaines pharmacothérapies (p. ex., antidépresseurs, antiandrogènes, antipsychotiques et anticonvulsifs) ont été proposées pour les symptômes qui ne répondent pas aux interventions non pharmacologiques. Par ailleurs, les données probantes à l’appui des traitements à l’aide de médicaments sont limitées, les effets secondaires demeurent un aspect important à considérer et il est incertain s’ils devraient être utilisés comme traitement de première ou de deuxième intention. Conclusion Quoiqu’il n’y ait pas d’algorithme de traitements empiriquement établi pour les CSI reliés à la démence, les ouvrages actuels offrent certaines données probantes concernant diverses thérapies pharmacologiques et non pharmacologiques. Des recherches de grande qualité plus approfondies sont nécessaires de toute urgence pour guider les médecins de famille qui prennent en charge des patients qui ont des CSI reliés à la

  16. Identification directe du comportement élastique endommageable de matériaux composites par la méthode des champs virtuels

    NASA Astrophysics Data System (ADS)

    Méraghni, F.; Chalal, H.; Pierron, F.; Grédiac, M.

    2002-12-01

    L'objectif de ce travail est de proposer une procédure d'identification directe de paramètres pilotant une loi de comportement de matériau composite dans le cadre d'un couplage élasticité-endommagement. Cette procédure est basée sur la Méthode des Champs Virtuels (MCV) utilisée ici avec des champs virtuels dits “ spéciaux et optimaux ”. Cette méthode permet de traiter les champs cinématiques hétérogènes. L'implémentation de loi de comportement dans le code de calcul par éléments finis ABAQUS a permis de simuler les cartographies de déformations hétérogènes exploitées par la MCV afin d'identifier le comportement global d'une structure composite sollicitée selon la configuration de l'essai Iosipescu (cisaillement). Une analyse des sensibilités a contribué à étudier les performances de la procédure en termes de précision et de stabilité vis à vis d'un bruit de mesure aléatoire.

  17. Comportement thermomécanique de l'argile de Boom

    NASA Astrophysics Data System (ADS)

    Sultan, Nabil; Delage, Pierre; Cui, Yu Jun

    Special attention has been recently paid on temperature effects on the behaviour of deep saturated clays, in relation with nuclear deep waste storage. However, few experimental data are presently available, and existing constitutive models need to be completed. This note is aimed at completing, both experimentally and theoretically, the understanding of the effects of the overconsolidation ratio on the thermal volume changes of Boom clay (Belgium). The experimental data obtained here are in a good agreement with existing data. As a complement to existing data, they are used to develop a new elastoplastic model. The adoption of a second coupled plastic mechanism provides good simulations on a complex thermo-mechanical path.

  18. Comparaison de deux modèles de comportement viscoplastique à variables internes

    NASA Astrophysics Data System (ADS)

    Lévêque, E.; Delobelle, P.

    1994-02-01

    The aim of this paper is about the comparison between two unified models with internal variables which have been established with 17-12MoSPH austenitic stainless steel experimental results. One is developed at the National Office of Aerospatial Research and Studies, the other, at the Applied Mechanical Laboratory of Besançon. The study proved their validity when applicated to a well known experimental loadings at high temperature, 500-600 °C. The two models report correctly the phenomena corresponding to classical loadings like monotonic traction, creep and cyclic hardening. However, there are important differences about transient creep and cyclic hardening under stress control. In the present state of the models, the progressive strain under uni or bidirectional loading (1D and 2D ratchet) is strongly overestimated. However, it is shown that it is possible to correctly describe the two types of progressive strain after taking into account a few modifications in the definition of the evolutionary laws for the tensorial variables of kinematical hardenings. Finally, the comparison does not allow to prefer one of the two models. Il s'agit dans cet article de comparer deux modèles viscoplastiques unifiés à variables internes établis à partir de résultats expérimentaux concernant l'acier austénitique inoxydable 17-12MoSPH ; l'un développé à l'Office National d'Etudes et Recherches Aérospatiales, l'autre au Laboratoire de Mécanique Appliquée de Besançon. L'étude a permis la validation des deux modèles par rapport à une base de données expérimentales aux températures élevées, 550 et 600 °C. Les deux modèles traduisent correctement les phénomènes inhérents à des chargements, classiques de traction monotone, fluage et d'écrouissage cyclique à déformation imposée. Par contre, on note des différences importantes en ce qui concerne l'hésitation au fluage et les essais cycliques à contrainte imposée. Dans leur version initiale les deux mod

  19. Apports de la simulation numérique pour I'identification du comportement rhéologique des alliages d'aluminium par essai de bipoinçonnement

    NASA Astrophysics Data System (ADS)

    Gélin, J. C.; Ghouati, O.; Shahani, R.

    1994-04-01

    The modelling of rheological behaviour of aluminium alloys for hot metal forming is based on experimental tests. The plane strain compression tests under various thermomechanical conditions (effective strain, effective strain rate, temperature, ...) are used for such a procedure. It is shown that numerical modelling combined with classical approaches can advantageously help in testing interpretation. It is shown, for instance, that the friction coefficient or the thermal exchanges between the specimen and the dies can be accurately fitted. Furthermore, a comparison between the numerical results and micrographical observations shows that it is possible to use numerical results with a good confidence. L'identification du comportement rhéologique des alliages d'aluminium en vue de leur mise en forme à chaud par laminage nécessite la réalisation d'essais expérimentaux. Les essais de bipoinçonnement entre poinçons parallélépipédiques, réalisés sous diverses conditions thermomécaniques (déformation effective, vitesse de déformation effective et température) ont été retenus pour une telle identification. On montre que la simulation numérique des essais permet de corriger de manière substantielle les méthodes d'identification classiques basées sur des approches rigides viscoplastiques. On montre par exemple que les simulations numériques permettent d'ajuster le coefficient de frottement ou les conditions d'échange thermiques. Enfin, une comparaison entre résultats numériques et analyses micrographiques montre que l'on peut utiliser les résultats des simulations en vue de la prévision des évolutions microstructurales des alliages considérés.

  20. Comportement en fatigue de l'aluminium 357 coule par gravite et rheocoule

    NASA Astrophysics Data System (ADS)

    Brochu, Myriam

    The primary objective of this work is to explain the fatigue strength difference between a permanent mold and a rheomolded material on the basis of the microstructural differences. The experimental work has been carried out using aluminum 357 alloy which was produced in six specimens characterized by different microstructures. This alloy was chosen because it is frequently used in the industry to produce automotive and aerospace components and because it is easy to rheomold. Also, this alloy has been widely used to develop the SEED technology. First, the microstructural characteristics and mechanical properties of the materials were quantified. This confirmed that the semi-solid molding (SSM) materials have a globular microstructure. The results also showed an increase of the yield strength attributed to rheomolding. However, among the four SSM materials, only those for which the eutectic structure was modified had higher elongation at fracture than the permanent mold materials. The highest measured elongation at fracture is 19% obtained for the modified SSM material, tested in the as-cast condition. The other materials tested all have an elongation at fracture below 10%. For both shaping process, results show that precipitation hardening is an efficient method of increasing the alloy yield strength. However, blisters formed while solutionizing the SSM materials which are detrimental to the metallurgical quality of the components. Consequently, the SSM materials were mostly tested in a T5 condition. The second portion of the work consisted in the production of S-N curves to study the fatigue strength differences between these materials and to identify the microstructures that are more resistant to high cycle fatigue. The results obtained at R = -1 showed that the SSM materials have a higher resistance to fatigue than the PM materials. Precipitation hardening was found to be less efficient in increasing the fatigue strength when compared to the materials yield

  1. Etude du comportement hydrogeologique de couvertures avec effet de barriere capillaire faites entierement de materiaux miniers

    NASA Astrophysics Data System (ADS)

    Kalonji, Alex Kabambi

    reclamation option through field experimental cells. If further research validates the laboratory results at the intermediate scale, the use of mining materials would be considered as an effective option for CCBE used to control post-closure pollution. This scenario could reduce the construction costs while promoting the social acceptability of mining projects by reducing the use of natural soils.

  2. Modèle de comportement dynamique d'un matériau en présence de l'endommagement par cisaillement adiabatique

    NASA Astrophysics Data System (ADS)

    Longère, P.; Dragon, A.; Trumel, H.; de Resseguier, T.; Deprince, X.; Petitpas, E.

    2002-12-01

    L'objectif industriel du travail dans lequel s'inscrit ce papier est la simulation numérique de la réponse de structures à l'impact. Or, pour un grand nombre de matériaux métalliques à haute résistance soumis à des sollicitations à grande vitesse, le cisaillement adiabatique constitue un processus endommageant conduisant souvent à la ruine par macrofissuration. Nous présentons ici un modèle continu qui, construit sur des bases thermodynamiques, rend compte du comportement thermo-élasto/viscoplastique du matériau sain et de l'anisotropie mécanique (dégradation directionnelle des modules élastiques et viscoplastiques induite par la présence des bandes de cisaillement adiabatique dans le matériau endommagé. Dans notre démarche de modélisation qui tend à refléter les constats expérimentaux, la population de bandes est représentée par une variable tensorielle d'endommagement au sein d'un matériau homogène équivalent. Le modèle est formulé dans le cadre des transformations finies élasto-plastiques avec prise en compte de l'anisotropie induite. Sa particularisation au cas des petites perturbations est illustrée pour certains processus homogènes.

  3. Modelisation du comportement micromecanique des alliages de titane en dwell-fatigue par la methode des automates cellulaires

    NASA Astrophysics Data System (ADS)

    Hamid Pourian, Meysam

    In this study, mathematical models based on the cellular automata (CA) method are developed to simulate the behavior of titanium alloys' microstructures under elastic, elastoplastic and dwell-fatigue loading. Within the CA model it is possible to identify cells that, according to defined damage criteria, can be favorable for crack initiation. The results of the CA model in elasticity and elastoplasticity are compared with a finite element (FE) model of polycrystalline aggregates in order to validate the CA model. Simulations of fatigue/creep are also done and the CA model results are compared with experimental observations. Local stress/strain distributions, the neighboring grains effects, residual stresses and the behavior of critical cells are studied and discussed. At the end of this work, the CA is proven to be an interesting method to study the micromechanical behavior of materials. Because of its simplicity this method can simulate and study complex behaviors for high number of cycles.

  4. Étude expérimentale du comportement cyclique d'un acier du type 316 L sous chargement multiaxial complexe en traction-torsion-pressions interne et externe

    NASA Astrophysics Data System (ADS)

    Bocher, L.; Delobelle, P.

    1997-09-01

    This paper is concerned with the experimental determination of the behaviour of a 316 L austenitic stainless steel at room temperature and under non proportional cyclic strainings in tension-torsion- internal and external pressures. The two or three sinusoïdal strains were applied both in and out-of-phase and the main investigations deal with the additional hardening due to multiaxiality of the loadings. Typical stabilized hysteresis loops are presented. With respect to the maximum additional hardening the different tests can be classified as follows : in phase tests, out-of-phase internal-external pressures tests, out-of-phase tension-torsion tests and finally tension-torsion-pressure with significant phase angles A device is presented which allows cyclic tests to be performed on tubes for loadings in tension-torsion-internal and external pressures. It is composed of a medium pressure chamber enclosing the gage length of the test specimen, directly fixed on the specimen and connected to two pressure regulators. The specimen is also fastened to the jaws of a hydraulic tensile-torsion machine through two extension rods. The entire device is controlled with the help of strain gauges set directly on the gage zone of the test specimen. Different tests have been performed at ambient temperature on an austenitic stainless steel which has the particularity of presenting a strong supplementary hardening connected to the non-radiality of the loadings. The influence of the phase shift parameters, namely the angles δ and \\varphi (δ: tension-torsion, \\varphi: tension-pressures) for two or three cyclic sinusoïdal components and for a total equivalent strain amplitude level imposed at 0.4% was studied. The ratios of the maximum strain amplitudes were respectively fixed at r_2 = 1 and r_1 = ± 1 (r_2: tension-torsion and r_1: tension-pressures). These tests allowed both the hypotheses made in stress calculations and the whole of the experimental set up to be validated. They

  5. Experimental Study of Sound Attenuation in Quasi-Monodisperse Emulsions

    NASA Astrophysics Data System (ADS)

    Herrmann, N.; Boltenhagen, P.; Lemaréchal, P.

    1996-10-01

    Very narrow size distribution oil-in-water emulsions have been prepared by using a recently proposed selective creaming method. The emulsions have been characterized by static and dynamic light scattering measurements. The ultrasonic absorption of the emulsions has been measured with an acoustic interferometer at frequencies between 0.5 and 10 MHz for a wide range of concentrations and droplets sizes. The comparison of the experimental results with existing theories shows an excellent agreement at oil volume fractions up to 0.15. The discrepancy between theory and experiments observed at higher volume fractions is attributed to thermal interactions between droplets for which a semi-quantitative model is proposed. Des émulsions d'huiles dans l'eau présentant une distribution en taille très étroite ont été préparées grâce à une méthode récemment proposée, fondée sur le crémage sélectif des goutelettes. Ces émulsions ont été caractérisées par diffusion statique et dynamique de la lumière. L'absorption ultrasonore des émulsions a été mesurée à l'aide d'un interféromètre acoustique à des fréquences comprises entre 0,5 et 10 MHz pour une large gamme de concentrations et de dimensions des gouttelettes. L'accord des résultats expérimentaux avec les théories existantes est excellent pour les fractions volumiques en huile inférieures à 15 %. L'écart entre théorie et expérience qui apparaît aux fractions volumiques plus élvées est attribué aux interactions thermiques entre gouttelettes, pour lesquelles un modèle semi-quantitatif est proposé.

  6. EXPHER (EXperimental PHysics ERror analysis): a Declaration Language and a Program Generator for the Treatment of Experimental Data

    NASA Astrophysics Data System (ADS)

    Weber, Philippe; Taupin, Daniel

    1995-05-01

    EXPHER refers to both a package — program generating compiler and library — which facilitates the treatment of a set of experimental data associated to a physical model, and a specification language describing the behaviour of the experimental devices, EXPHER yields a compilable program whose execution determines the most likely values of the parameters involved in the physical model, but also their error bars and their comprehensive error matrix. EXPHER est à la fois un logiciel — compilateur et générateur de programme, avec une bibliothèque associée — facilitant le traitement d'une série de données expérimentales associée à un modèle de physique et un langage de spécification du comportement de l'appareillage expérimental. À partir de cette description de l'appareillage, EXPHER produit un programme compilable dont l'exécution détermine les valeurs les plus probables de paramètres du modèle physique, leur barre d'erreur et la matrice d'erreurs finale.

  7. Experimental Pi.

    ERIC Educational Resources Information Center

    Corris, G.

    1990-01-01

    Discusses the calculation of pi by means of experimental methods. Polygon circle ratios, Archimedes' method, Buffon's needles, a Monte Carlo method, and prime number approaches are used. Presents three BASIC programs for the calculations. (YP)

  8. Experimental philosophy.

    PubMed

    Knobe, Joshua; Buckwalter, Wesley; Nichols, Shaun; Robbins, Philip; Sarkissian, Hagop; Sommers, Tamler

    2012-01-01

    Experimental philosophy is a new interdisciplinary field that uses methods normally associated with psychology to investigate questions normally associated with philosophy. The present review focuses on research in experimental philosophy on four central questions. First, why is it that people's moral judgments appear to influence their intuitions about seemingly nonmoral questions? Second, do people think that moral questions have objective answers, or do they see morality as fundamentally relative? Third, do people believe in free will, and do they see free will as compatible with determinism? Fourth, how do people determine whether an entity is conscious?

  9. Étude du comportement associatif du copolymère tribloc poly(1,4-phénylène)-b-polystyrène-b-poly(1,4-phénylène) en solution

    NASA Astrophysics Data System (ADS)

    Mignard, E.; Tachon, C.; François, B.

    1998-06-01

    Poly(1,4-phenylene)-b-polystyrene-b-poly(1,4-phenylene) (PPP-b- PS-b-PPP) block copolymers were synthesized by chemical modification of a precursor copolymer. After characterization by Size Exclusion Chromatography (S.E.C) and U.V. spectroscopy, PPP-b-PS-b-PPP copolymers were studied in THF solution at room temperature by viscosimetry and light-scattering analysis. We have shown the associative behavior of these triblock copolymers by their ability to form, with this molecular weight distribution, aggregates with a possible “flower-like" morphology constituted of a PPP “core" surrounded by PS “petals". Des copolymères à blocs poly(1,4-phénylène)-b-polystyrène-b-poly (1,4-phénylène) (PPP-b-PS-b-PPP) ont été synthétisés par modification chimique d'un copolymère précurseur. Après caractérisation par Chromatographie d'Exclusion Stérique (C.E.S.) et par spectroscopie U.V., les copolymères PPP-b-PS-b-PPP ont été étudiés en solution dans le THF à température ambiante par viscosimétrie et diffusion de la lumière. Nous avons observé le comportement associatif de ces copolymères triblocs par leur aptitude à former, pour la distribution de masses molaires étudiée, des agrégats ayant vraisemblablement une morphologie semblable à celle d'une “fleur" possédant un “cour" de PPP et des “pétales" de PS.

  10. Animal experimentation.

    PubMed

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  11. Experimental macroevolution†

    PubMed Central

    Bell, Graham

    2016-01-01

    The convergence of several disparate research programmes raises the possibility that the long-term evolutionary processes of innovation and radiation may become amenable to laboratory experimentation. Ancestors might be resurrected directly from naturally stored propagules or tissues, or indirectly from the expression of ancestral genes in contemporary genomes. New kinds of organisms might be evolved through artificial selection of major developmental genes. Adaptive radiation can be studied by mimicking major ecological transitions in the laboratory. All of these possibilities are subject to severe quantitative and qualitative limitations. In some cases, however, laboratory experiments may be capable of illuminating the processes responsible for the evolution of new kinds of organisms. PMID:26763705

  12. Prévision de l'effet hygrothermique sur le comportement mécanique d'un composite stratifié équilibré carbone HR/époxyde

    NASA Astrophysics Data System (ADS)

    Mili, F.; Lekrine, A.; Necib, B.; Bradai, C.

    2005-05-01

    La prévision de l'effet de l'environnement, humidité et température, sur le comportement mécanique des structures en matériaux composites constitue l'axe principal de cette étude. Nous nous intéressons à la résistance ultime en traction du matériau composite à renforcement unidirectionnel carbone HR/époxyde travaillant dans des milieux hygrothermiques différents. Ce problème fait donc apparaître des déformations d'échelle macroscopique liées au changement de la séquence d'empilement du stratifié et la variation du degré d'anisotropie du matériau. L'utilisation de critères de résistance permet de prévoir la rupture du pli composant le moins résistant, de déterminer les différents modes de rupture et zones d'endommagement des stratifiés équilibrés [ +θ/-θ]4S et de caractériser le tenseur de déformation des plaques [ +45/-45]4S, [0/90]4S et [0/+45]4S. Les résultats ainsi obtenus montrent que la variation de la température d'utilisation et de l'humidité relative en fonction de l'orientation des fibres confère au matériau des caractéristiques mécaniques spéciales. De plus, ils fournissent des ressources objectives aux calculs visant à optimiser les performances de la structure sollicitée grâce à une connaissance de l'évolution des paramètres de résistance et des mécanismes d'endommagement du composite.

  13. Simulation du comportement thermique en régime permanent d'un moteur asynchrone à refroidissement extérieur. Etude par éléments finis

    NASA Astrophysics Data System (ADS)

    Glises, R.; Hostache, G.; Kauffmann, J. M.

    1994-09-01

    The steady state thermal modelling of an 4kW asynchronous motor is realized. A design has been made thanks to the Flux2D finite element magnetic calculus software converted into a resolution tool of the heat equation. This last is used to simulate the heat flux in fluid and solid areas. A 3D study is effected thanks to two 2D studies. The first concerns a radial view (perpendicular to the mechanical axis) whereas the second is effected for an axial view (parallel to the mechanical axis). Thermal conductivities of the materials and thermal contact resistances of the motor are determined through two different tests creating different overheatings. The first is made with a sinewave supply and pre-determine the thermophysical parameters. The second effected with direct current supplies at the rotor and the stator is used to validate these last parameters. On réalise l'étude du comportement thermique en régime permanent d'un moteur asynchrone de 4kW. Le logiciel de calculs magnétiques par éléments finis flux2D est converti en un outil de résolution de l'équation de la chaleur. Cette dernière équation sert à simuler les transferts thermiques tant dans les domaines fluides que solides. Une pseudo-étude tridimensionnelle est réalisée par le biais de deux études bidimensionnelles : la première effectuée suivant un plan radial (plan perpendiculaire à l'axe du moteur) et la seconde suivant un plan axial (plan parallèle à l'axe). Les conductivités des matériaux et des résistances thermiques de contact composant le moteur sont déterminées à l'aide de deux types d'essais qui induisent des échauffements différents. Le premier est réalisé avec une alimentation sinusoïdale et sert à prédéterminer les paramètres thermophysiques. Le second est effectué avec des alimentations à courant continu tant au stator qu'au rotor et a pour rôle la validation de ces paramètres.

  14. Etude du comportement sous charges laterales des ossatures de beton arme avec murs de remplissage de maconnerie, construites avant les annees 1960

    NASA Astrophysics Data System (ADS)

    Lefebvre, Karine

    yielding sequence (beam versus columns versus infills). The identified parameters are the presence of the infills, the openings and the geometric characteristics of the models (number of storeys and number of bays). One important contribution of this work is the development of an equivalent strut model to represent the action of the infill. The model could be easily implemented in standard analysis software. A central axial hinge reproducing the nonlinear behaviour of the masonry is added to the strut element. This model is a hybridization of existing proposals (FEMA and others) with added innovations by the author. It has been validated with experimental and numerical analyses results from literature. An important conclusion of this thesis is that the contribution of infills to lateral load resisting capacities of BMR structures should be considered for structure of more than one storey. Infills can add up to 51 % to bare frame capacity. The National building code requires that the lateral resistance of existing buildings must be at least 60 % of the equivalent static seismic force (V2005). It is concluded that one storey BMR buildings have a sufficient resistance, while three-storeys structures exhibit plastic deformations for loads under 0,6* V2005.

  15. Coordination des regulateurs conventionnels des machines Synchrones et des Compensateurs Statiques (SVCs)

    NASA Astrophysics Data System (ADS)

    Zabaiou, Tarik

    This thesis proposes a new control design method based on wide-area measurements to coordinate generator excitations and Static Var Compensator (SVC) auxiliary controls. A state space model of a multimachine power system that includes a SVC is first derived. This model has several specific characteristics. The interactions between SVC and generator variables are clearly shown and the interactions among the generators are also quantified. Generators terminal voltages are used as state variables instead of internal field voltages and damper winding flux linkages. The benefit is that the proposed model state variables are easily measurable. Moreover, it is a hierarchical approach and suitable for wide-area control design in large power systems. Next, remote measurements are used to generate coordinating signals for the generator excitations and the SVC. The coordinating controller decouples the system dynamics by compensating the interaction terms. The effectiveness of the new control strategy is tested on Anderson and Farmer four-generator nine-bus power system. Simulation results demonstrate that both local and inter-area oscillations are well damped when the global controller is used. Furthermore, Relative Gain Array (RGA) theory is proposed to evaluate the interactions and to select the input global signals for the coordinate controller. Only signals that contribute to the strongest interactions are used by the controller to considerably reduce or eliminate the interactions between the system components. The second controller with a reduced set of measurements is compared to the first controller with full measurements. Results show that performances of both controllers are very similar. They provide significant additional damping for power oscillations and increase the power transfer in the system. Communication time delay effects are also considered in this study. The simulation results show that coordinating controller performances are excellent when realistic transmission delays are represented. However, in presence of large measurement and control delays the performance of the controller is considerably affected. A Smith predictor is proposed to recover the delay free performances. The simulation results prove that impacts of large communication time delays are efficiently compensated using the Smith prediction method. The proposed wide-area coordinating controller is simple and easy to implement since it requires only one measurement from each generator and the SVC as inputs and the controller provides one control signal for the SVC and each of the generators. It could be cost effective to use the proposed controller rather than the installation of new FACTS devices. Keywords: coordination, hierarchical control, inter-area oscillations, FACTS controllers, power systems modeling, Relative Gain Array (RGA), Static Var Compensator (SVC), Wide-Area Control.

  16. Effets de l'interaction avec l'oxygène sur le comportement de couches semi-conductrices de ZnO, SnO{2} et CdSe

    NASA Astrophysics Data System (ADS)

    Ain-Souya, A.; Ghers, M.; Haddad, A.; Tebib, W.; Rehamnia, R.; Messsalhi, A.; Bounouala, M.; Djouama, M. C.

    2005-05-01

    Les propriétés superficielles des matériaux solides diffèrent de celles du volume. A la surface, des défauts de différentes natures peuvent être présents. Ils permettent à la surface d'être interactive avec le milieu ambiant. Les multiples interactions entre les états de surface et des éléments du milieu extérieur peuvent modifier les propriétés superficielles. Ce travail étudie la régénération de couches semi-conductrices après adsorption isotherme d'oxygène à différentes températures effectuées entre 20 ° C et 300 ° C. Les matériaux qui ont servi à l'étude sont des couches de ZnO, SnO{2} et CdSe. Celles de CdSe ont été obtenues par co-évaporation, sous vide, de cadmium et de sélénium. Les échantillons de ZnO et SnO{2} ont été élaborés par oxydation, à des températures respectives de 450 ° C et 200 ° , de Zn et Sn déposés par électrolyse et par évaporation sous vide. Les matériaux évaporés ont été déposés sur des plaquettes en verre, les autres ont été électrodéposés sur des substrats métalliques. Les variations des propriétés électriques des couches ont été suivies par mesure de leur résistance électrique superficielle R. Les courbes LogR = f (103 /T (K)), relevées sous vide à différentes températures, sont caractéristiques d'un comportement de semi-conducteur. Des essais d'adsorption d'O{2} à différentes températures montrent des variations considérables de R. En effet, la chimisorption forte d'un gaz par une surface semi-conductrice est telle que l'échange électronique entre adsorbant et adsorbat provoque la formation d'une zone de charge d'espace modifiant la conduction superficielle. Les résultats mettent en évidence des domaines de température de plus haute sensibilité à l'oxygène. Pour le CdSe, certaines désorptions isothermes ont été suffisantes pour une régénération totale des échantillons. Les couches de ZnO ont souvent nécessité des désorptions programm

  17. Is animal experimentation fundamental?

    PubMed

    d'Acampora, Armando José; Rossi, Lucas Félix; Ely, Jorge Bins; de Vasconcellos, Zulmar Acciolli

    2009-01-01

    The understanding about the utilization of experimental animals in scientific research and in teaching is many times a complex issue. Special attention needs to be paid to attain the understanding by the general public of the importance of animal experimentation in experimental research and in undergraduate medical teaching. Experimental teaching and research based on the availability of animals for experimentation is important and necessary for the personal and scientific development of the physician-to-be. The technological arsenal which intends to mimic experimentation animals and thus fully replace their use many times does not prove to be compatible with the reality of the living animal. The purpose of this paper is to discuss aspects concerning this topic, bringing up an issue which is complex and likely to arouse in-depth reflections.

  18. The Experimental College.

    ERIC Educational Resources Information Center

    Meiklejohn, Alexander

    "The Experimental College" tells the story of a 4-year academic experiment at the University of Wisconsin established by Alexander Meiklejohn. Aimed at finding a method of teaching that would help students develop "intelligence in the conduct of their own lives," the Experimental College discarded major requirements,…

  19. On experimental oil spills

    SciTech Connect

    Mackay, D.; Thornton, D. E.; Blackall, P. J.; Sergy, G. S.; Snow, N.; Hume, H.

    1980-09-01

    Experimental oil spills are an essential component of overall oil pollution research efforts. However, such experiments must be carefully designed and coordinated in order to cull the most information possible. Physical, biological, and ecological impacts must be examined simultaneously. Long-term monitoring of the multidisciplinary effects of experimental oil spills is recommended.

  20. Questioning and Experimentation

    ERIC Educational Resources Information Center

    Mutanen, Arto

    2014-01-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated…

  1. 7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL ...

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

    7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL FOREST BUNKHOUSE, FERNOW EXPERIMENTAL FOREST GARAGE, AND FERNOW EXPERIMENTAL FOREST RESIDENCE. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

  2. Magnetohydrodynamic generator experimental studies

    NASA Technical Reports Server (NTRS)

    Pierson, E. S.

    1972-01-01

    The results for an experimental study of a one wavelength MHD induction generator operating on a liquid flow are presented. First the design philosophy and the experimental generator design are summarized, including a description of the flow loop and instrumentation. Next a Fourier series method of treating the fact that the magnetic flux density produced by the stator is not a pure traveling sinusoid is described and some results summarized. This approach appears to be of interest after revisions are made, but the initial results are not accurate. Finally, some of the experimental data is summarized for various methods of excitation.

  3. Experimental Semiotics: A Review

    PubMed Central

    Galantucci, Bruno; Garrod, Simon

    2010-01-01

    In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience. PMID:21369364

  4. Summary of experimental talks

    SciTech Connect

    Derrick, M.

    1999-12-08

    This final talk of the meeting briefly discussed a number of experimental topics that the author found particularly interesting in the area of High Energy Physics. It also includes some critical comments about the future direction of their discipline.

  5. Nuclear test experimental science

    SciTech Connect

    Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S.

    1989-01-01

    This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research.

  6. Experimental scattershot boson sampling

    PubMed Central

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-01-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

  7. SPHINX experimenters information package

    SciTech Connect

    Zarick, T.A.

    1996-08-01

    This information package was prepared for both new and experienced users of the SPHINX (Short Pulse High Intensity Nanosecond X-radiator) flash X-Ray facility. It was compiled to help facilitate experiment design and preparation for both the experimenter(s) and the SPHINX operational staff. The major areas covered include: Recording Systems Capabilities,Recording System Cable Plant, Physical Dimensions of SPHINX and the SPHINX Test cell, SPHINX Operating Parameters and Modes, Dose Rate Map, Experiment Safety Approval Form, and a Feedback Questionnaire. This package will be updated as the SPHINX facilities and capabilities are enhanced.

  8. Questioning and Experimentation

    NASA Astrophysics Data System (ADS)

    Mutanen, Arto

    2014-08-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated model can be interpreted realistically. Moreover, the model demonstrates an explicit logic of knowledge acquisition. So, the natural extension of the model is to apply it to an analysis of the learning process.

  9. Experimental probes of axions

    SciTech Connect

    Chou, Aaron S.; /Fermilab

    2009-10-01

    Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

  10. The Experimental College.

    ERIC Educational Resources Information Center

    Meiklejohn, Alexander; Powell, John Walker, Ed.

    In the early twentieth century, Alexander Meiklejohn believed the undergraduate college must teach students how to think. He aspired to make students into thinking, caring, active citizens with the intellectual skills to participate in a democratic society. In 1927, with the founding of the Experimental College at the University of Wisconsin, he…

  11. Experimental fluvial geomorphology

    SciTech Connect

    Schumm, S.A.; Mosley, M.P.; Weaver, W.

    1987-01-01

    The authors bring together the results of several years of experimental work in drainage basin evolution, hydrology, river-channel morphology, and sedimentology. These investigations are related to real-world applications, particularly geological exploration and mapping. This text shows how awareness of natural phenomena can improve management of the natural environment, such as the control of rivers and eroding gullies.

  12. Communicating Uncertain Experimental Evidence

    ERIC Educational Resources Information Center

    Davis, Alexander L.; Fischhoff, Baruch

    2014-01-01

    Four experiments examined when laypeople attribute unexpected experimental outcomes to error, in foresight and in hindsight, along with their judgments of whether the data should be published. Participants read vignettes describing hypothetical experiments, along with the result of the initial observation, considered as either a possibility…

  13. EXPERIMENTAL ANIMAL MAINTENANCE

    DOEpatents

    Finkel, M.P.

    1962-01-22

    A method of housing experimental animals such as mice in individual tube- like plastic enclosures is described. Contrary to experience, when this was tried with metal the mice did not become panicky. Group housing, with its attendant difficulties, may thus be dispensed with. (AEC)

  14. Structure initiale et propriétés de liquéfaction statique d'un sable

    NASA Astrophysics Data System (ADS)

    Benahmed, Nadia; Canou, Jean; Dupla, Jean-Claude

    2004-11-01

    Based on the use of two different preparation procedures for reconstituting triaxial samples of sand, i.e. wet tamping and dry pluviation, significant differences in associated mechanical behaviour are observed on a reference sand with respect to the phenomenon of 'static' liquefaction. Wet tamping favours the initiation of liquefaction instability, whereas dry pluviation favours a more stable behaviour, less susceptible to liquefaction. Microscopic observation of corresponding sand specimens allows us to identify two well differentiated structures, i.e., for wet tamping, an irregular structure with predominance of aggregates (aggregated grains) and macropores, very contractant and unstable and, for dry pluviation, a more regular structure, without macropores, more dilatant and more stable. These observations show the importance of further characterization, based on the introduction of appropriate parameters, of the initial structure of sandy materials, strongly dependant upon their mode of formation (natural or artificial). To cite this article: N. Benahmed et al., C. R. Mecanique 332 (2004).

  15. Évolution quasi-statique d'un fil souple inextensible sur un plan avec frottement sec : cas discret

    NASA Astrophysics Data System (ADS)

    Sayah, Hafid

    2004-02-01

    The differential inclusion describing the quasi-static motion of a supple, homogeneous and inextensible string on a horizontal plane with dry friction (Coulomb's law) is a one dimensional evolution model of a continuous medium, with non-linear geometry, obeying a "plastic-rigid" law. With a view to numerical simulation, we treat the discrete case: the string is assimilated to a chain constituted by rigid rods perfectly articulated around ball-joints. We give variational formulation of the problem and prove existence and uniqueness of solutions. We construct an algorithm that describes the instantaneous solutions when the initial configuration of the string is given. Then, some examples are treated. To cite this article: H. Sayah, C. R. Mecanique 332 (2004).

  16. Anisotropie magnetique du La2NiMnO6 multiferroique par magnetometrie statique et spectroscopie de resonance ferromagnetique

    NASA Astrophysics Data System (ADS)

    Chagnon, Dany

    In this research, magnetic properties of thin films composed of both double- (La2NiMnO6 or LNMOo) and simple-perovskites (LaNi0.5Mn0.5O3 ou LNMOd) are studied. This mixt phase (LNMOm) possesses two magnetic transitions; one for each phase present. It has previously been shown that this phase possesses a higher Curie temperature than LNMOo, approaching room temperature. This property makes room temperature ferromagnetic resonance measurements possible. Angular FMR measurement has already been achieved, but the magnetic anisotropy resulting isn’t completely understood. The goal of this study is to increase our understanding of this anisotropy to get new informations on the structure of the samples. To achieve this goal, thin films of LNMOm have been deposited by PLD on three different substrates; LSAT(001), LSAT(011) and LSAT(111). LSAT has been chosen for his insulating properties limiting the losses in the microwave cavities used for FMR measurements and for his very smooth surface. One sample of LNMOm on LAO(001) was also fabricated by Mangala Singh from the laboratoire des matériaux quantiques during a summer internship of the author. Some of the results obtained on this sample were used in this work. The samples were first characterized using static magnetometry. All samples possess two magnetic transitions, one at low temperature corresponding to the disordered phase and one at high temperature corresponding to the ordered phase. The temperature of these transitions were obtained with precision using the inflection point method. The high temperature transition was then confirmed using magnetocaloric effect, which gave the exact same values. The transition temperature of the ordered phase of all samples was between 268 and 271 K, while the transition of the disordered phase was between 60 and 110 K. A third transition at really low temperature was observed on some samples. The volume and volumic fraction of the ordered and disordered phases were approximated by comparing the saturated magnetization of each sample with the expected values at different temperatures. Finally, thermomagnetic processes were observed in all samples. These measurements suggests a more complex microstructure in the sample on LSAT(111) than in the sample on LSAT(011) which is consistent with the anisotropy observed by FMR spectroscopy. FMR characterization has then been performed. The magnetic anisotropy of the different samples was studied at 24 GHz and at room temperature. All samples possess two groups of peaks wich are attributed to different parts of the thin film, a wetting film and a region in which the strains are relaxed. The dominant source of anisotropy seems to be magnetostatic, produced by the shape of ordered clusters in the disordered matrix. Four anisotropy axis were observed on the sample grown on LSAT(001), which is consistent with a monoclinic crystalline structure inducing preferential growth orientations in four directions. Weak cubic magnetocrystalline anisotropy has been observed for the wetting film. This anisotropy suggest a rotation of 45° between the lattice of the substrate and the lattice of the film. Measurements at different frequencies allowed us to compare a curve of the anisotropy field in function of the resonance field with a curve of magnetization in function of the applied magnetic field. Comparison of these curves allowed us to determine a shape factor of the ordered clusters of approximately 1, corresponding to very flat ellipsoid. Different measurements allowed us to get a g-factor of approximately 2, corresponding to that of a free spin. Finally, temperature dependence of resonance field and full width at half maximum are shown. The variation of these parameters corresponds to the expected behavior.

  17. Administrative Aspects of Human Experimentation.

    ERIC Educational Resources Information Center

    Irvine, George W.

    1992-01-01

    The following administrative aspects of scientific experimentation with human subjects are discussed: the definition of human experimentation; the distinction between experimentation and treatment; investigator responsibility; documentation; the elements and principles of informed consent; and the administrator's role in establishing and…

  18. Experimental design and husbandry.

    PubMed

    Festing, M F

    1997-01-01

    Rodent gerontology experiments should be carefully designed and correctly analyzed so as to provide the maximum amount of information for the minimum amount of work. There are five criteria for a "good" experimental design. These are applicable both to in vivo and in vitro experiments: (1) The experiment should be unbiased so that it is possible to make a true comparison between treatment groups in the knowledge that no one group has a more favorable "environment." (2) The experiment should have high precision so that if there is a true treatment effect there will be a good chance of detecting it. This is obtained by selecting uniform material such as isogenic strains, which are free of pathogenic microorganisms, and by using randomized block experimental designs. It can also be increased by increasing the number of observations. However, increasing the size of the experiment beyond a certain point will only marginally increase precision. (3) The experiment should have a wide range of applicability so it should be designed to explore the sensitivity of the observed experimental treatment effect to other variables such as the strain, sex, diet, husbandry, and age of the animals. With in vitro data, variables such as media composition and incubation times may also be important. The importance of such variables can often be evaluated efficiently using "factorial" experimental designs, without any substantial increase in the overall number of animals. (4) The experiment should be simple so that there is little chance of groups becoming muddled. Generally, formal experimental designs that are planned before the work starts should be used. (5) The experiment should provide the ability to calculate uncertainty. In other words, it should be capable of being statistically analyzed so that the level of confidence in the results can be quantified.

  19. Geoengineering as Collective Experimentation.

    PubMed

    Stilgoe, Jack

    2016-06-01

    Geoengineering is defined as the 'deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming'. The technological proposals for doing this are highly speculative. Research is at an early stage, but there is a strong consensus that technologies would, if realisable, have profound and surprising ramifications. Geoengineering would seem to be an archetype of technology as social experiment, blurring lines that separate research from deployment and scientific knowledge from technological artefacts. Looking into the experimental systems of geoengineering, we can see the negotiation of what is known and unknown. The paper argues that, in renegotiating such systems, we can approach a new mode of governance-collective experimentation. This has important ramifications not just for how we imagine future geoengineering technologies, but also for how we govern geoengineering experiments currently under discussion.

  20. Experimental temporal quantum steering

    NASA Astrophysics Data System (ADS)

    Bartkiewicz, Karol; Černoch, Antonín; Lemr, Karel; Miranowicz, Adam; Nori, Franco

    2016-11-01

    Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering.

  1. Experimental temporal quantum steering

    PubMed Central

    Bartkiewicz, Karol; Černoch, Antonín; Lemr, Karel; Miranowicz, Adam; Nori, Franco

    2016-01-01

    Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering. PMID:27901121

  2. MSFC Skylab experimenter's reference

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The methods and techniques for experiment development and integration that evolved during the Skylab Program are described to facilitate transferring this experience to experimenters in future manned space programs. Management responsibilities and the sequential process of experiment evolution from initial concept through definition, development, integration, operation and postflight analysis are outlined in the main text and amplified, as appropriate, in appendixes. Emphasis is placed on specific lessons learned on Skylab that are worthy of consideration by future programs.

  3. Experimental Neutrino Physics

    ScienceCinema

    Walter, Chris [Duke University, Durham, North Carolina, United States

    2016-07-12

    In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

  4. Woodward Effect Experimental Verifications

    NASA Astrophysics Data System (ADS)

    March, Paul

    2004-02-01

    The work of J. F. Woodward (1990 1996a; 1996b; 1998; 2002a; 2002b; 2004) on the existence of ``mass fluctuations'' and their use in exotic propulsion schemes was examined for possible application in improving space flight propulsion and power generation. Woodward examined Einstein's General Relativity Theory (GRT) and assumed that if the strong Machian interpretation of GRT as well as gravitational / inertia like Wheeler-Feynman radiation reaction forces hold, then when an elementary particle is accelerated through a potential gradient, its rest mass should fluctuate around its mean value during its acceleration. Woodward also used GRT to clarify the precise experimental conditions necessary for observing and exploiting these mass fluctuations or ``Woodward effect'' (W-E). Later, in collaboration with his ex-graduate student T. Mahood, they also pushed the experimental verification boundaries of these proposals. If these purported mass fluctuations occur as Woodward claims, and his assumption that gravity and inertia are both byproducts of the same GRT based phenomenon per Mach's Principle is correct, then many innovative applications such as propellantless propulsion and gravitational exotic matter generators may be feasible. This paper examines the reality of mass fluctuations and the feasibility of using the W-E to design propellantless propulsion devices in the near to mid-term future. The latest experimental results, utilizing MHD-like force rectification systems, will also be presented.

  5. SAA drift: Experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Romashova, V. V.; Petrov, A. N.

    According to the paleomagnetic analysis there are variations of Earth’s magnetic field connected with magnetic moment changing. These variations affect on the South Atlantic Anomaly (SAA) location. Indeed different observations approved the existence of the SAA westward drift rate (0.1 1.0 deg/year) and northward drift rate (approximately 0.1 deg/year). In this work, we present the analysis of experimental results obtained in Scobeltsyn Institute of Nuclear Physics, Moscow State University (SINP MSU) onboard different Earth’s artificial satellites (1972 2003). The fluxes of protons with energy >50 MeV, gamma quanta with energy >500 keV and neutrons with energy 0.1 1.0 MeV in the SAA region have been analyzed. The mentioned above experimental data were obtained onboard the orbital stations Salut-6 (1979), MIR (1991, 1998) and ISS (2003) by the similar experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact that the SAA drifts westward. Moreover the analysis of fluxes of electrons with energy about hundreds keV (Cosmos-484 (1972) and Active (Interkosmos-24, 1991) satellites) verified not only the SAA westward drift but northward drift also.

  6. Genetics of experimental hypertension.

    PubMed

    Dominiczak, A F; Clark, J S; Jeffs, B; Anderson, N H; Negrin, C D; Lee, W K; Brosnan, M J

    1998-12-01

    Experimental models of genetic hypertension are used to develop paradigms to study human essential hypertension while removing some of the complexity inherent in the study of human subjects. Since 1991 several quantitative trait loci responsible for blood pressure regulation have been identified in various rat crosses. More recently, a series of interesting quantitative trait loci influencing cardiac hypertrophy, stroke, metabolic syndrome and renal damage has also been described. It is recognized that the identification of large chromosomal regions containing a quantitative trait locus is only a first step towards gene identification. The next step is the production of congenic strains and substrains to confirm the existence of the quantitative trait locus and to narrow down the chromosomal region of interest. Several congenic strains have already been produced, with further refinement of the methodology currently in progress. The ultimate goal is to achieve positional cloning of the causal gene, a task which has so far been elusive. There are several areas of cross-fertilization between experimental and human genetics of hypertension, with a successful transfer of two loci directly from rats to humans and with new pharmacogenetic approaches which may be utilized in both experimental and clinical settings.

  7. Experimental alcohol blastopathy.

    PubMed

    Sandor, S

    1988-01-01

    Experimental data are presented with respect to "experimental alcohol blastopathy" performed in our laboratory. As in our interpretation the notion of blastopathy involves both pathological changes during preimplantation development due to previous, preconceptional or preimplantation influences and later, pre- or postnatal effects induced by factors active during the preimplantation period, up to now the following experimental models were applied (on rats and mice): chronic and acute maternal, biparental or paternal ethanol alcoholization; preimplantation treatment with acetaldehyde or disulfiram followed by ethanol administration; acute ethanol intoxication before implantation on the background of chronic maternal ethanol intake; chronic maternal intake of various beverages. The main components of experimental alcohol blastopathy detected (by using a complex control methodology) were: pathological changes during the preimplantation developmental stages (lower mean number of embryos/animal, retardation of development, lowered migration rate of the embryos from the oviduct to the uterus, higher number of pathological morphological features), delayed implantation, disturbances of the early postimplantation development, retarded late foetal and placental growth. The effect of ethanol may be direct (ethanol being detectable in the oviductal and uterine fluid after both acute and chronic alcoholization) or indirect, via changes of the maternal macro- or microenvironment. The increase of the maternal blood acetaldehyde level may contribute to the appearance of alcohol blastopathy. Chronic beer and wine intake and acute intoxication with cognac suggest - up to now - the enhancing effect of beverage congeners. The noxious effect of acute ethanol intoxication superposed to chronic alcoholization is more marked that the separate effect of the two kinds of treatment. The chronic ethanol intake of fertilizing males (in mice) leads, both in the case of treated or untreated

  8. Experimental turbine VT-400

    NASA Astrophysics Data System (ADS)

    Zitek, Pavel; Milčák, Petr; Noga, Tomáš

    2016-03-01

    The experimental air turbine VT400 is located in hall laboratories of the Department of Power System Engineering. It is a single-stage air turbine located in the suction of the compressor. It is able to solve various problems concerning the construction solution of turbine stages. The content of the article will deal mainly with the description of measurements on this turbine. The up-to-now research on this test rig will be briefly mentioned, too, as well as the description of the ongoing reconstruction.

  9. Experimental models of stress

    PubMed Central

    Patchev, Vladimir K.; Patchev, Alexandre V.

    2006-01-01

    Illustrating the complexity of the stress response and its multifaceted manifestations is the leading idea of this overview of experimental paradigms used for stress induction in laboratory animals. The description of key features of models based on naturalistic stressors, pharmacological challenges, and genomic manipulations is complemented by comprehensive analysis of physiological, behavioral, neurochemical, and endocrine changes and their appropriatness as outcome readouts. Particular attention has been paid to the role of sex and age as determinants of the dynamics of the stress response. Possible translational applications of stress-inducing paradigms as models of disease are briefly sketched. PMID:17290800

  10. EXPERIMENTAL ANIMAL WATERING DEVICE

    DOEpatents

    Finkel, M.P.

    1964-04-01

    A device for watering experimental animals confined in a battery of individual plastic enclosures is described. It consists of a rectangular plastic enclosure having a plurality of fluid-tight compartments, each with a drinking hole near the bottom and a filling hole on the top. The enclosure is immersed in water until filled, its drinking holes sealed with a strip of tape, and it is then placed in the battery. The tape sealing prevents the flow of water from the device, but permits animals to drink by licking the drinking holes. (AEC)

  11. Outsourcing of experimental work.

    PubMed

    Nielsen, Henrik

    2011-01-01

    With the development of new technologies for simultaneous analysis of many genes, transcripts, or proteins (the "omics" revolution), it has become common to outsource parts of the experimental work. In order to maintain the integrity of the research projects, it is important that the interphase between the researcher and the service is further developed. This involves robust protocols for sample preparation, an informed choice of analytical tool, development of standards for individual technologies, and transparent data analysis. This chapter introduces some of the problems related to analysis of RNA samples in the "omics" context and gives a few hints and key references related to sample preparation for the non-specialist.

  12. [Animal experimentation in Israel].

    PubMed

    Epstein, Yoram; Leshem, Micah

    2002-04-01

    In 1994 the Israeli parliament (Knesset) amended the Cruelty to Animals Act to regulate the use of experimental animals. Accordingly, animal experiments can only be carried out for the purposes of promoting health and medical science, reducing suffering, advancing scientific research, testing or production of materials and products (excluding cosmetics and cleaning products) and education. Animal experiments are only permitted if alternative methods are not possible. The National Board for Animal Experimentation was established to implement the law. Its members are drawn from government ministries, representatives of doctors, veterinarians, and industry organizations, animal rights groups, and academia. In order to carry out an animal experiment, the institution, researchers involved, and the specific experiment, all require approval by the Board. To date the Board has approved some 35 institutions, about half are public institutions (universities, hospitals and colleges) and the rest industrial firms in biotechnology and pharmaceutics. In 2000, 250,000 animals were used in research, 85% were rodents, 11% fowls, 1,000 other farm animals, 350 dogs and cats, and 39 monkeys. Academic institutions used 74% of the animals and industry the remainder. We also present summarized data on the use of animals in research in other countries.

  13. Experimentation in machine discovery

    NASA Technical Reports Server (NTRS)

    Kulkarni, Deepak; Simon, Herbert A.

    1990-01-01

    KEKADA, a system that is capable of carrying out a complex series of experiments on problems from the history of science, is described. The system incorporates a set of experimentation strategies that were extracted from the traces of the scientists' behavior. It focuses on surprises to constrain its search, and uses its strategies to generate hypotheses and to carry out experiments. Some strategies are domain independent, whereas others incorporate knowledge of a specific domain. The domain independent strategies include magnification, determining scope, divide and conquer, factor analysis, and relating different anomalous phenomena. KEKADA represents an experiment as a set of independent and dependent entities, with apparatus variables and a goal. It represents a theory either as a sequence of processes or as abstract hypotheses. KEKADA's response is described to a particular problem in biochemistry. On this and other problems, the system is capable of carrying out a complex series of experiments to refine domain theories. Analysis of the system and its behavior on a number of different problems has established its generality, but it has also revealed the reasons why the system would not be a good experimental scientist.

  14. Experimental Models of Pancreatitis

    PubMed Central

    Hyun, Jong Jin

    2014-01-01

    Acute pancreatitis is an inflammatory disease characterized by interstitial edema, inflammatory cell infiltration, and acinar cell necrosis, depending on its severity. Regardless of the extent of tissue injury, acute pancreatitis is a completely reversible process with evident normal tissue architecture after recovery. Its pathogenic mechanism has been known to be closely related to intracellular digestive enzyme activation. In contrast to acute pancreatitis, chronic pancreatitis is characterized by irreversible tissue damage such as acinar cell atrophy and pancreatic fibrosis that results in exocrine and endocrine insufficiency. Recently, many studies of chronic pancreatitis have been prompted by the discovery of the pancreatic stellate cell, which has been identified and distinguished as the key effector cell of pancreatic fibrosis. However, investigations into the pathogenesis and treatment of pancreatitis face many obstacles because of its anatomical location and disparate clinical course. Due to these difficulties, most of our knowledge on pancreatitis is based on research conducted using experimental models of pancreatitis. In this review, several experimental models of pancreatitis will be discussed in terms of technique, advantages, and limitations. PMID:24944983

  15. Future experimental programs

    NASA Astrophysics Data System (ADS)

    Murayama, Hitoshi

    2013-12-01

    I was asked to discuss future experimental programs even though I am a theorist. As a result, I present my own personal views on where the field is, and where it is going, based on what I myself have been working on. In particular, I discuss why we need expeditions into high energies to find clues to where the relevant energy scale is for dark matter, baryon asymmetry and neutrino mass. I also argue that the next energy frontier machine should be justified on the basis of what we know, namely the mass of the Higgs boson, so that we will learn what energy we should aim at once we nail the Higgs sector. Finally, I make remarks on dark energy.

  16. Experimental traumatic brain injury

    PubMed Central

    2010-01-01

    Traumatic brain injury, a leading cause of death and disability, is a result of an outside force causing mechanical disruption of brain tissue and delayed pathogenic events which collectively exacerbate the injury. These pathogenic injury processes are poorly understood and accordingly no effective neuroprotective treatment is available so far. Experimental models are essential for further clarification of the highly complex pathology of traumatic brain injury towards the development of novel treatments. Among the rodent models of traumatic brain injury the most commonly used are the weight-drop, the fluid percussion, and the cortical contusion injury models. As the entire spectrum of events that might occur in traumatic brain injury cannot be covered by one single rodent model, the design and choice of a specific model represents a major challenge for neuroscientists. This review summarizes and evaluates the strengths and weaknesses of the currently available rodent models for traumatic brain injury. PMID:20707892

  17. Experimental evolution gone wild

    PubMed Central

    Scheinin, M.; Riebesell, U.; Rynearson, T. A.; Lohbeck, K. T.; Collins, S.

    2015-01-01

    Because of their large population sizes and rapid cell division rates, marine microbes have, or can generate, ample variation to fuel evolution over a few weeks or months, and subsequently have the potential to evolve in response to global change. Here we measure evolution in the marine diatom Skeletonema marinoi evolved in a natural plankton community in CO2-enriched mesocosms deployed in situ. Mesocosm enclosures are typically used to study how the species composition and biogeochemistry of marine communities respond to environmental shifts, but have not been used for experimental evolution to date. Using this approach, we detect a large evolutionary response to CO2 enrichment in a focal marine diatom, where population growth rate increased by 1.3-fold in high CO2-evolved lineages. This study opens an exciting new possibility of carrying out in situ evolution experiments to understand how marine microbial communities evolve in response to environmental change. PMID:25833241

  18. Fusion of experimental data

    NASA Astrophysics Data System (ADS)

    Di Gesú, Vito; Maccarone, Maria Concetta

    The integration of information from various sensory systems is one of the most difficult challenges in understanding both perception and cognition. For example, the problem of auditory-visual integration is a correspondence problem between perceived auditory and visual scenes. Two main questions arise when designing data analysis systems: what is the useful information to be integrated?, and what are the integration rules? The problem of integrating information becomes relevant whenever: (a) the same kind of data are detected by spatially distributed sensors; (b) heterogeneous data are detected by different sensors; (c) heterogeneous distributed data are involved. General problems concerning the integration of experimental data are reviewed. The case of the BeppoSAX X-ray astronomical satellite is given as an example.

  19. Experimental adaptive process tomography

    NASA Astrophysics Data System (ADS)

    Pogorelov, I. A.; Struchalin, G. I.; Straupe, S. S.; Radchenko, I. V.; Kravtsov, K. S.; Kulik, S. P.

    2017-01-01

    Adaptive measurements were recently shown to significantly improve the performance of quantum state tomography. Utilizing information about the system for the online choice of optimal measurements allows one to reach the ultimate bounds of precision for state reconstruction. In this article we generalize an adaptive Bayesian approach to the case of process tomography and experimentally show its superiority in the task of learning unknown quantum operations. Our experiments with photonic polarization qubits cover all types of single-qubit channels. We also discuss instrumental errors and the criteria for evaluation of the ultimate achievable precision in an experiment. It turns out that adaptive tomography provides a lower noise floor in the presence of strong technical noise.

  20. Experimentalism in bioethics research.

    PubMed

    Ackerman, T F

    1983-05-01

    Basson's commentary on my proposals regarding the structure and function of research in bioethics provides a welcome opportunity for extended comparison of standard approaches with the suggestions made in 'What Bioethics Should Be.' I begin by noting a common assumption underlying our respective views. I then address points of fundamental difference, indicating why the experimental method proposed in my original essay presents a potentially more productive strategy for examining moral issues in biomedicine. In the latter respect, I certainly disagree with Basson's contention that "we are unable to test" metaethical hypotheses "against reality" (Basson, p. 185) - a proposition which seems no more defensible than the equally untenable claim that we cannot refine methods of natural science research through examination of their usefulness in advancing our understanding of the correlation of events in nature.

  1. An Experimental LISP Machine

    NASA Astrophysics Data System (ADS)

    Lun, Wang

    1987-04-01

    This paper presents a multi-microprocessor LISP machine whose goal is to exploit the inherent parallelism in the LISP programs fully. The base architecture is a MIMD architecture based on a hybrid model for combinating data driven, demand driven and VoN Neumann process schemes. The basic evaluation strategy is data driven. Lazy evaluation mechanism is introduced to avoid unnecessary and unsafe computations. An experimental system with the four processor elements has been built in HIT, China. The system consists of a Z80 microcomputer and three TP8O1s interconnected through three buses. Each processor evaluates a part of programs asynchronously. The shared memory is divided into two parts: list cell area and enviroment area, each of which has the indepen-dent common bus to avoid the bus bottleneck.

  2. Planetary impact experimentation

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.; Schultz, Peter H.; Hoerz, Friedrich

    1987-01-01

    An understanding of impact processes in low- and microgravity environments would be advanced significantly by the construction and use of an impact facility on the Space Station. It is proposed that initial studies begin as soon as possible in ground-based impact laboratories, on the NASA KC-135 Reduced-Gravity Aircraft, and in existing drop towers. The resulting experience and information base could then be applied toward an experiment package designed for use on Shuttle orbiters to support pilot studies in orbital environments. These experiments, as well as the first efforts made on the IOC Space Station, should involve the impact of various free-floating targets; such studies would yield a substantial scientific return while providing valuable experience and engineering information for use in refining the design of the dedicated Space Station Impact Facility. The dedicated facility should be designed to support impact experimentation, including but not limited to cratering, asteroid and ring-particle dynamics, and accretional processes.

  3. Experimental Quantum Coin Tossing

    NASA Astrophysics Data System (ADS)

    Molina-Terriza, G.; Vaziri, A.; Ursin, R.; Zeilinger, A.

    2005-01-01

    In this Letter we present the first implementation of a quantum coin-tossing protocol. This protocol belongs to a class of “two-party” cryptographic problems, where the communication partners distrust each other. As with a number of such two-party protocols, the best implementation of the quantum coin tossing requires qutrits, resulting in a higher security than using qubits. In this way, we have also performed the first complete quantum communication protocol with qutrits. In our experiment the two partners succeeded to remotely toss a row of coins using photons entangled in the orbital angular momentum. We also show the experimental bounds of a possible cheater and the ways of detecting him.

  4. Experimental Sloshing Reference Test

    NASA Astrophysics Data System (ADS)

    Lada, C.; Such-Taboada, M.; Ngan, I.; Grigore, L.; Appolloni, M.; Roure, S.; Murray, N.; Mendes Leal, M.; de Wilde, D.; Longo, J.; Bureo-Dacal, R.; Cozzani, A.; Laine, B.

    2014-06-01

    This article describes the sloshing experiment performed on the HYDRA multi-axis hydraulic shaker at ESTEC. Two tank geometries, a rectangular tank and a pill shaped tank, were excited in the lateral direction. Both tanks, manufactured from a transparent material in order to provide high visibility of the phenomenon, were filled with water and several fill ratios were tested, varying the amplitude of the input and the sweep rate. The results of the test are presented from a structural point of view, with the main objective to study the interface force due to dynamic fluid sloshing motion. An investigation of the behaviour of the water around the main resonance of the assembly is conducted through the observation of the identified modes and the damping values. The experimental results confirm the amplification effect at low frequency caused by water sloshing motion and a comparison with data from numerical simulation is provided.

  5. Experimental Literacy Assessment Battery (LAB).

    DTIC Science & Technology

    READING, * LITERACY , EDUCATION, HUMAN RESOURCES, MODELS, EXPERIMENTAL DESIGN, AIR FORCE TRAINING, LANGUAGE, RESOURCE MANAGEMENT, PSYCHOLOGICAL TESTS, VOCABULARY, INFORMATION PROCESSING, COMPREHENSION.

  6. Experimental Particle Physics

    SciTech Connect

    Rosenfeld, Carl; Mishra, Sanjib R.; Petti, Roberto; Purohit, Milind V.

    2014-08-31

    The high energy physics group at the University of South Carolina, under the leadership of Profs. S.R. Mishra, R. Petti, M.V. Purohit, J.R. Wilson (co-PI's), and C. Rosenfeld (PI), engaged in studies in "Experimental Particle Physics." The group collaborated with similar groups at other universities and at national laboratories to conduct experimental studies of elementary particle properties. We utilized the particle accelerators at the Fermi National Accelerator Laboratory (Fermilab) in Illinois, the Stanford Linear Accelerator Center (SLAC) in California, and the European Center for Nuclear Research (CERN) in Switzerland. Mishra, Rosenfeld, and Petti worked predominantly on neutrino experiments. Experiments conducted in the last fifteen years that used cosmic rays and the core of the sun as a source of neutrinos showed conclusively that, contrary to the former conventional wisdom, the "flavor" of a neutrino is not immutable. A neutrino of flavor "e," "mu," or "tau," as determined from its provenance, may swap its identity with one of the other flavors -- in our jargon, they "oscillate." The oscillation phenomenon is extraordinarily difficult to study because neutrino interactions with our instruments are exceedingly rare -- they travel through the earth mostly unimpeded -- and because they must travel great distances before a substantial proportion have made the identity swap. Three of the experiments that we worked on, MINOS, NOvA, and LBNE utilize a beam of neutrinos from an accelerator at Fermilab to determine the parameters governing the oscillation. Two other experiments that we worked on, NOMAD and MIPP, provide measurements supportive of the oscillation experiments. Good measurements of the neutrino oscillation parameters may constitute a "low energy window" on related phenomena that are otherwise unobservable because they would occur only at energies way above the reach of conceivable accelerators. Purohit and Wilson participated in the BaBar experiment

  7. Particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Boynton, P.E.; Burnett, T.H.; Wilkes, R.J.

    1991-08-21

    We are continuing a research program in particle astrophysics and high energy experimental particle physics. We have joined the DUMAND Collaboration, which is constructing a deep undersea astrophysical neutrino detector near Hawaii. Studies of high energy hadronic interactions using emulsion chamber techniques were also continued, using balloon flight exposures to ultra-high cosmic ray nuclei (JACEE) and accelerator beams. As members of the DUMAND Collaboration, we have responsibility for development a construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustical positioning system required to permit reconstruction of muon tracks with sufficient precision to meet the astrophysical goals of the experiment. In addition, we are making significant contributions to the design of the database and triggering system to be used. Work has been continuing in other aspects of the study of multiparticle production processes in nuclei. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators, using balloon-borne emulsion chambers. On one of the flights we found two nuclear interactions of multiplicity over 1000 -- one with a multiplicity of over 2000 and pseudorapidity density {approximately} 800 in the central region. At the statistical level of the JACEE experiment, the frequency of occurrence of such events is orders of magnitude too large. We have continued our ongoing program to study hadronic interactions in emulsions exposed to high energy accelerator beams.

  8. Experimental Toxoplasmosis in Chimpanzees

    PubMed Central

    Draper, C. C.; Killick-Kendrick, R.; Hutchison, W. M.; Siim, J. Chr.; Garnham, P. C. C.

    1971-01-01

    Two chimpanzees were given by mouth large numbers of viable oocysts of Toxoplasma gondii obtained from the faeces of experimentally infected cats. Before the experiment the first chimpanzee had a positive dye test reaction (1:250), an indication that it had undergone an earlier infection of toxoplasmosis; the serum antibody titres remained unchanged, no evidence of illness was found, and oocysts did not appear in its faeces during the subsequent six weeks. The second chimpanzee showed a negative dye test reaction before infection, and this converted to positive on the 7th day, rose to a peak on the 35th day, and remained high for six months. This animal appeared unwell during the first week, and on the 7th day its blood proved infective to mice; on the 40th day the lymph nodes became enlarged and biopsy specimens of a node and muscle in the 11th week were also infective to mice. No oocysts were passed in the faeces. The presumed cycle in the chimpanzee and in man and the relationships between Toxoplasma and Isospora are discussed. PMID:5575975

  9. Experimental quantum data locking

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Zhu; Wu, Cheng; Fukuda, Daiji; You, Lixing; Zhong, Jiaqiang; Numata, Takayuki; Chen, Sijing; Zhang, Weijun; Shi, Sheng-Cai; Lu, Chao-Yang; Wang, Zhen; Ma, Xiongfeng; Fan, Jingyun; Zhang, Qiang; Pan, Jian-Wei

    2016-08-01

    Classical correlation can be locked via quantum means: quantum data locking. With a short secret key, one can lock an exponentially large amount of information in order to make it inaccessible to unauthorized users without the key. Quantum data locking presents a resource-efficient alternative to one-time pad encryption which requires a key no shorter than the message. We report experimental demonstrations of a quantum data locking scheme originally proposed by D. P. DiVincenzo et al. [Phys. Rev. Lett. 92, 067902 (2004), 10.1103/PhysRevLett.92.067902] and a loss-tolerant scheme developed by O. Fawzi et al. [J. ACM 60, 44 (2013), 10.1145/2518131]. We observe that the unlocked amount of information is larger than the key size in both experiments, exhibiting strong violation of the incremental proportionality property of classical information theory. As an application example, we show the successful transmission of a photo over a lossy channel with quantum data (un)locking and error correction.

  10. Réponses transitoires de films de TiO{2}, capteurs résistifs du gaz oxygène

    NASA Astrophysics Data System (ADS)

    Jérisian, R.; Loup, J. P.; Gautron, J.

    1991-07-01

    We analyse the mecanisms of the transient response of TiO2-film EGO (Exhaust Gas Oxygen) sensors to partial oxygen pressure. This analysis, in agreement with the steady-state behaviour, is based upon the diffusion theory. Moreover, our results corroborate the decrease of the response time when Pt is incorporated to the film or when the thickness of the film is lessened. Nous analysons les réponses transitoires de capteurs résistifs de films de TiO2 soumis à des changements de pression partielle d'oxygène. Cette analyse fait appel à la théorie de la diffusion et reste en accord avec l'étude du comportement statique de ces capteurs. Les temps de réponse mesurés décroissent avec l'incorporation de Pt ou la diminution de l'épaisseur du film.

  11. Experimental Deformation of Magnetite

    NASA Astrophysics Data System (ADS)

    Till, J. L.; Rybacki, E.; Morales, L. F. G.

    2015-12-01

    Magnetite is an important iron ore mineral and the most prominent Fe-oxide phase in the Earth's crust. The systematic occurrence of magnetite in zones of intense deformation in oceanic core complexes suggests that it may play a role in strain localization in some silicate rocks. We performed a series of high-temperature deformation experiments on synthetic magnetite aggregates and natural single crystals to characterize the rheological behavior of magnetite. As starting material, we used fine-grained magnetite powder that was hot isostatically pressed at 1100°C for several hours, resulting in polycrystalline material with a mean grain size of around 40 μm and containing 3-5% porosity. Samples were deformed to 15-20% axial strain under constant load (approximating constant stress) conditions in a Paterson-type gas apparatus for triaxial deformation at temperatures between 900 and 1100°C and 300 MPa confining pressure. The aggregates exhibit typical power-law creep behavior. At high stresses, samples deformed by dislocation creep exhibit stress exponents close to 3, revealing a transition to near-Newtonian creep with stress exponents around 1.3 at lower stresses. Natural magnetite single crystals deformed at 1 atm pressure and temperatures between 950°C and 1150 °C also exhibit stress exponents close to 3, but with lower flow stresses and a lower apparent activation energy than the aggregates. Such behavior may result from the different oxygen fugacity buffers used. Crystallographic-preferred orientations in all polycrystalline samples are very weak and corroborate numerical models of CPO development, suggesting that texture development in magnetite may be inherently slow compared with lower symmetry phases. Comparison of our results with experimental deformation data for various silicate minerals suggests that magnetite should be weaker than most silicates during ductile creep in dry igneous rocks.

  12. X-38 Experimental Aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; Berry, Scott A.; Merski, N. Ronald; Fitzgerald, Steve M.

    2000-01-01

    The X-38 program seeks to demonstrate an autonomously returned orbital test flight vehicle to support the development of an operational Crew Return Vehicle for the International Space Station. The test flight, anticipated in 2002, is intended to demonstrate the entire mission profile of returning Space Station crew members safely back to earth in the event of medical or mechanical emergency. Integral to the formulation of the X-38 flight data book and the design of the thermal protection system, the aerothermodynamic environment is being defined through a synergistic combination of ground based testing and computational fluid dynamics. This report provides an overview of the hypersonic aerothermodynamic wind tunnel program conducted at the NASA Langley Research Center in support of the X-38 development. Global and discrete surface heat transfer force and moment, surface streamline patterns, and shock shapes were measured on scaled models of the proposed X-38 configuration in different test gases at Mach 6, 10 and 20. The test parametrics include angle of attack from 0 to 50 degs, unit Reynolds numbers from 0.3 x 10 (exp 6) to 16 x 10 (exp 6)/ ft, rudder deflections of 0, 2, and 5 deg. and body flap deflections from 0 to 30 deg. Results from hypersonic aerodynamic screening studies that were conducted as the configuration evolved to the present shape at, presented. Heavy gas simulation tests have indicated that the primary real gas effects on X-38 aerodynamics at trim conditions are expected to favorably influence flap effectiveness. Comparisons of the experimental heating and force and moment data to prediction and the current aerodynamic data book are highlighted. The effects of discrete roughness elements on boundary layer transition were investigated at Mach 6 and the development of a transition correlation for the X-38 vehicle is described. Extrapolation of ground based heating measurements to flight radiation equilibrium wall temperatures at Mach 6 and 10 were

  13. [Experimental nuclear physics

    SciTech Connect

    Not Available

    1992-12-01

    An earlier study of unusual electromagnetic decays in {sup 86}Zr was extended in order to make comparisons with its isotone {sup 84}Sr and with {sup 84}Zr. The K=14 (t {sub {1/2}} = 70 ns) high-spin isomer in {sup 176}W was found to have a 13% branch directly to the K=O ground-state band, one of the strongest violations of K-selection rules known. A new program to search for a predicted region of oblate deformation involving neutron deficient isotopes in the Rn/Fr/Ra region was begun. In the area of nuclear astrophysics, as part of a study of the onset of the rp-Process, a set of measurements searching for possible new resonances for {sup 14}O+{alpha} and {sup 17}F+p reactions was completed and a coincidence experiment measuring the {sup 19}F({sup 3}He,t){sup 19}Ne({alpha}){sup 15}O and {sup 19}F({sup 3}He,t){sup 19}Ne(p){sup 18}F reactions in order to determine the rates of the {sup 18}F(p,{alpha}){sup 15}O and {sup 18}F(p,{gamma}){sup 19}Ne reactions was begun. Experimental measurements of {beta}n{alpha} coincidences from the {sup 15}N(d,p){sup 16}N({beta}{sup {minus}}{nu}){sup 16}O({alpha}){sup 12}C reaction have also been completed and are currently being analyzed to determine the rate of the {sup 12}C({alpha},{gamma}) reaction. In the APEX collaboration, we have completed the assembly and testing of two position-sensitive Na barrels which surround the axial silicon detector arrays and serve as the e{sup +} triggers by detecting their back-to-back annihilation quanta were completed. The HI@AGS and RHIC collaborations, construction and implementation activities associated with the space-time-tracker detector and in the design of the central detector for the PHENIX experiment were carried out. Operation of the ESTU tandem accelerator has been reliable, delivering beam on target at terminal voltages as high as 19.3 MV and running for as long as 143 days between tank openings. Fabrication and bench testing of a new negative ion source system have been completed.

  14. Superconductive Microwave Single-Flux-Quantum Digital Circuits and Corresponding Opto-Electronic Interfaces: On-Going Studies and First Experimental Results

    DTIC Science & Technology

    2005-07-13

    UHLMANN University of Technology Ilmenau– PO Box 105565 – D-98684 Ilmenau - Germany RESUME : Les circuits numériques supraconducteurs micro-ondes...circuits RSFQ. Ce banc de mesure comporte deux types d’interfaces opto-RSFQ, basées sur des matériaux semiconducteurs et supraconducteurs , respectivement

  15. Experimental Design and Some Threats to Experimental Validity: A Primer

    ERIC Educational Resources Information Center

    Skidmore, Susan

    2008-01-01

    Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

  16. Majorana Thermosyphon Prototype Experimental Setup

    SciTech Connect

    Reid, Douglas J.; Guzman, Anthony D.; Munley, John T.

    2011-08-01

    This report presents the experimental setup of Pacific Northwest National Laboratory’s MAJORANA DEMONSTRATOR thermosyphon prototype cooling system. A nitrogen thermosyphon prototype of such a system has been built and tested at PNNL. This document presents the experimental setup of the prototype that successfully demonstrated the heat transfer performance of the system.

  17. Experimental Learning Enhancing Improvisation Skills

    ERIC Educational Resources Information Center

    Pereira Christopoulos, Tania; Wilner, Adriana; Trindade Bestetti, Maria Luisa

    2016-01-01

    Purpose: This study aims to present improvisation training and experimentation as an alternative method to deal with unexpected events in which structured processes do not seem to work. Design/Methodology/Approach: Based on the literature of sensemaking and improvisation, the study designs a framework and process model of experimental learning…

  18. Experimental Mathematics and Computational Statistics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-04-30

    The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.

  19. Assessing Pupils' Skills in Experimentation

    ERIC Educational Resources Information Center

    Hammann, Marcus; Phan, Thi Thanh Hoi; Ehmer, Maike; Grimm, Tobias

    2008-01-01

    This study is concerned with different forms of assessment of pupils' skills in experimentation. The findings of three studies are reported. Study 1 investigates whether it is possible to develop reliable multiple-choice tests for the skills of forming hypotheses, designing experiments and analysing experimental data. Study 2 compares scores from…

  20. Psychopharmacology's debt to experimental psychology.

    PubMed

    Schmied, Lori A; Steinberg, Hannah; Sykes, Elizabeth A B

    2006-05-01

    The role of experimental psychology in the development of psychopharmacology has largely been ignored in recent historical accounts. In this article the authors attempt to redress that gap by outlining work in early experimental psychology that contributed significantly to the field. While psychiatrists focused on the therapeutic nature of drugs or their mimicry of psychopathology, experimental psychologists used psychoactive drugs as tools to study individual differences in normal behavior as well as to develop methodologies using behavior to study mechanisms of drug action. Experimental work by Kraepelin, Rivers, and Hollingworth was particularly important in establishing drug-screening protocols still used today. Research on nitrous oxide and on the effects of drug combinations is discussed to illustrate the importance of experimental psychology to psychopharmacology.

  1. Experimentation on humans and nonhumans.

    PubMed

    Pluhar, Evelyn B

    2006-01-01

    In this article, I argue that it is wrong to conduct any experiment on a nonhuman which we would regard as immoral were it to be conducted on a human, because such experimentation violates the basic moral rights of sentient beings. After distinguishing the rights approach from the utilitarian approach, I delineate basic concepts. I then raise the classic "argument from marginal cases" against those who support experimentation on nonhumans but not on humans. After next replying to six important objections against that argument, I contend that moral agents are logically required to accord basic moral rights to every sentient being. I conclude by providing criteria for distinguishing ethical from unethical experimentation.

  2. The Beginnings of Experimental Petrology

    ERIC Educational Resources Information Center

    Eugster, Hans P.

    1971-01-01

    An account of Van't Hoff's change from theoretical chemistry to petrology provides data on the European intellectual climate of the early 1900's and shows how his work laid the foundation for experimental petrology of hard rocks." (AL)

  3. Experimental studies: randomized clinical trials.

    PubMed

    Gjorgov, A N

    1998-01-01

    There are two major approaches to medical investigations: observational studies and experimental trials. The classical application of the experimental design to studies of human populations is the randomized clinical trial of the efficacy of a new drug or treatment. A further application of the experimental studies is to the testing of hypotheses about the etiology of a disease, already tested and corroborated from various forms of observational studies. Ethical considerations and requirements for consent of the experimental subjects are of primary concern in the clinical trials, and those concerns set the first and final limits for implementing a trial. General moral principles in research with human and animal beings, defined by the "Nuremberg Code," deal with strict criteria for approval, endorsement and evaluation of a clinical trial.

  4. Animal Experimentation in High Schools

    ERIC Educational Resources Information Center

    Ansevin, Kystyna D.

    1970-01-01

    Recommends that teacher and student be provided with the broadest possible spectrum of meaningful and feasible experiments in which the comfort of the experimental animal is protected by the design of the experiment. (BR)

  5. Experimental models of uveal melanoma.

    PubMed

    Blanco, Paula L; Caissie, Amanda L; Burnier, Miguel N

    2004-06-01

    Over the past several decades, considerable effort has been directed toward developing suitable experimental models for the study of uveal melanoma. Animal models of uveal melanoma have undergone many improvements, leading to the development of experimental systems that better represent the disease in human beings. A major advance has come from the use of human uveal melanoma cell lines capable of inducing tumour growth and metastatic disease in immunodeficient hosts. Knowledge gained from the use of experimental models will ultimately be translated into better diagnostic and therapeutic strategies for patients with uveal melanoma. In this review the authors describe the current state-of-the-art designs of experimental models of uveal melanoma, highlighting the advantages and disadvantages of the available models. Novel findings from a rabbit model of uveal melanoma are also presented.

  6. [The ethics of animal experimentation].

    PubMed

    Goffi, Jean-Yves

    2013-01-01

    The paper starts with a short definition of animal experimentation, then three main approaches to the practice are considered: unconditional approval (as advocated by Claude Bernard), conditional and restricted approval (as advocated by Peter Singer) and strict prohibition (as advocated by Tom Regan and Gary Francione). It is argued that what is actually approved or condemned in animal experimentation is the value of the scientific enterprise.

  7. Experimental Approach to Teaching Fluids

    NASA Astrophysics Data System (ADS)

    Stern, Catalina

    2015-11-01

    For the last 15 years we have promoted experimental work even in the theoretical courses. Fluids appear in the Physics curriculum of the National University of Mexico in two courses: Collective Phenomena in their sophomore year and Continuum Mechanics in their senior year. In both, students are asked for a final project. Surprisingly, at least 85% choose an experimental subject even though this means working extra hours every week. Some of the experiments were shown in this congress two years ago. This time we present some new results and the methodology we use in the classroom. I acknowledge support from the Physics Department, Facultad de Ciencias, UNAM.

  8. Qualitative tools and experimental philosophy

    PubMed Central

    Andow, James

    2016-01-01

    Abstract Experimental philosophy brings empirical methods to philosophy. These methods are used to probe how people think about philosophically interesting things such as knowledge, morality, and freedom. This paper explores the contribution that qualitative methods have to make in this enterprise. I argue that qualitative methods have the potential to make a much greater contribution than they have so far. Along the way, I acknowledge a few types of resistance that proponents of qualitative methods in experimental philosophy might encounter, and provide reasons to think they are ill-founded.

  9. Graphical Models for Quasi-Experimental Designs

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter M.; Hall, Courtney E.; Su, Dan

    2016-01-01

    Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

  10. Experimental Neutrino Physics: Final Report

    SciTech Connect

    Lane, Charles E.; Maricic, Jelena

    2012-09-05

    Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

  11. Big Explosives Experimental Facility - BEEF

    SciTech Connect

    2014-10-31

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  12. Experimental Disability: A Gestalt Perspective.

    ERIC Educational Resources Information Center

    Lofaro, Gregory A.; James, Fleming, III

    1980-01-01

    Experimental disability offers rehabilitation counselor educators and trainers a vehicle for developing student-counselor awareness and sensitivity to psychosocial problems of disability. Gestalt counseling techniques, which emphasize the bipolarities of the disability experience, are used to explore the feelings, behaviors, and attitudes…

  13. Learning Experimentation through Science Fairs

    ERIC Educational Resources Information Center

    Paul, Jürgen; Lederman, Norman G.; Groß, Jorge

    2016-01-01

    Experiments are essential for both doing science and learning science. The aim of the German youth science fair, "Jugend forscht," is to encourage scientific thinking and inquiry methods such as experimentation. Based on 57 interviews with participants of the competition, this study summarises students' conceptions and steps of learning…

  14. Evaluating E-Labs' Experimentation

    ERIC Educational Resources Information Center

    Plaisent, Michel; Maguiraga, Lassana; Bernard, Prosper; Larhrib, Samir

    2004-01-01

    This communication discusses preliminary results on an experimentation of e-Learning with MIS students, mainly in order to cope with the logistics of lab organization. A learning management software was installed which changed completely the learning process, from content to logistics. Students have expressed their satisfaction with the e-Learning…

  15. [Ethical issue in animal experimentation].

    PubMed

    Parodi, André-Laurent

    2009-11-01

    In the 1970s, under pressure from certain sections of society and thanks to initiatives by several scientific research teams, committees charged with improving the conditions of laboratory animals started to be created, first in the United States and subsequently in Europe. This led to the development of an ethical approach to animal experimentation, taking into account new scientific advances. In addition to the legislation designed to provide a legal framework for animal experimentation and to avoid abuses, this ethical approach, based on the concept that animals are sentient beings, encourages greater respect of laboratory animals and the implementation of measures designed to reduce their suffering. Now, all animal experiments must first receive ethical approval--from in-house committees in the private sector and from regional committees for public institutions. Very recently, under the impetus of the French ministries of research and agriculture, the National committee for ethical animal experimentation published a national ethical charter on animal experimentation, setting the basis for responsible use of animals for scientific research and providing guidelines for the composition and functioning of ethics committees. Inspired by the scientific community itself this ethical standardization should help to assuage--but not eliminate--the reticence and hostility expressed by several sections of society.

  16. Big Explosives Experimental Facility - BEEF

    ScienceCinema

    None

    2016-07-12

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  17. An experimenter and his methodology

    NASA Astrophysics Data System (ADS)

    Filonovich, S. R.

    1990-12-01

    A review of experimental works by Ernst Mach has been given. The works reffer to optics and acoustics. The author is representing Ernst Mach as a physicist rather than a phylosopher, which contradicts the point of view obviously accepted in Soviet history of sciences and philosophy.

  18. Experimental Evidence for the Pentaquark

    SciTech Connect

    D.S. Carman

    2005-02-01

    The present experimental evidence for the existence of light pentaquarks is reviewed, including both positive and null results. I also discuss the CLAS experiments at Jefferson Laboratory that are forthcoming in the near future to address questions regarding existence, mass, width, and other quantum numbers of these five-quark baryon states.

  19. Rheology of welding: experimental constraints

    NASA Astrophysics Data System (ADS)

    Quane, S. L.; Russell, J. K.; Kennedy, L. A.

    2003-04-01

    The rheological behavior of pyroclastic deposits during welding is incompletely understood and is based on a surprisingly small number of experimental studies. Previous pioneering experimental studies were done on small (1 cm thick) samples of ash/crystal mixtures under constant load. They established minimum welding temperatures between 600 and 700^oC under loads of 0.7 MPa (˜40 m of ignimbrite) to 3.6 MPa (˜250 m depth of ignimbrite). However, these data are neither sufficiently comprehensive nor coherent enough to fully describe the rheology of pyroclastic mixtures. In addition, previous studies did not examine the microstructural and geometric changes associated with welding compaction. Our goal is to provide accurate and comprehensive constitutive relationships between material properties, temperature, load and strain rate for pyroclastic material undergoing welding. Here we present results from a newly designed experimental apparatus. The experimental apparatus consists of a LoadTrac II fully automated uniaxial compression load frame manufactured by Geocomp Corporation. The load frame has a built in displacement transducer and can run both constant strain rate (10-6 to 0.25 cm/s) and constant load (up to 1150 kg) tests to a maximum displacement of 7.5 cm. The sample assembly comprises 5 cm diameter cylindrical upper and lower pistons (insulating ceramic with steel conductive ends) housed in a copper jacket. Samples are 5 cm diameter cores and can vary in length from 1 to 15 cm depending on experimental needs. A fiber insulated tube furnace capable of reaching temperatures ≈1000^oC surrounds the sample assembly. Temperature is measured using a thermocouple located inside the sample through the bottom piston; the furnace controller is capable of maintaining temperature fluctuations to <5^oC. Deformation experiments are performed on pre-fabricated cylinders of soda-lime glass beads and rhyolitic volcanic ash, as well as, cores of pumiceous rhyodacite

  20. Experimental Unconditionally Secure Bit Commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-01

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10-2 cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints.

  1. Experimental unconditionally secure bit commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adan; Pan, Jian-Wei

    2014-03-01

    Quantum physics allows unconditionally secure communication between parties that trust each other. However, when they do not trust each other such as in the bit commitment, quantum physics is not enough to guarantee security. Only when relativistic causality constraints combined, the unconditional secure bit commitment becomes feasible. Here we experimentally implement a quantum bit commitment with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. Bits are successfully committed with less than 5 . 68 ×10-2 cheating probability. This provides an experimental proof of unconditional secure bit commitment and demonstrates the feasibility of relativistic quantum communication.

  2. Experimental lithium system. Final report

    SciTech Connect

    Kolowith, R.; Berg, J.D.; Miller, W.C.

    1985-04-01

    A full-scale mockup of the Fusion Materials Irradiation Test (FMIT) Facility lithium system was built at the Hanford Engineering Development Laboratory (HEDL). This isothermal mockup, called the Experimental Lithium System (ELS), was prototypic of FMIT, excluding the accelerator and dump heat exchanger. This 3.8 m/sup 3/ lithium test loop achieved over 16,000 hours of safe and reliable operation. An extensive test program demonstrated satisfactory performance of the system components, including the HEDL-supplied electromagnetic lithium pump, the lithium jet target, the purification and characterization hardware, as well as the auxiliary argon and vacuum systems. Experience with the test loop provided important information on system operation, performance, and reliability. This report presents a complete overview of the entire Experimental Lithium System test program and also includes a summary of such areas as instrumentation, coolant chemistry, vapor/aerosol transport, and corrosion.

  3. Experimental research on air propellers

    NASA Technical Reports Server (NTRS)

    Durand, William F

    1918-01-01

    The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.

  4. Multimodal MRI of experimental stroke

    PubMed Central

    Duong, Timothy Q

    2014-01-01

    Stroke is the fourth leading cause of death and the leading cause of long-term disability in the United States. Brain imaging data from experimental stroke models and stroke patients have shown that there is often a gradual progression of potentially reversible ischemic injury toward infarction. Reestablishing tissue perfusion and/or treating with neuroprotective drugs in a timely fashion are expected to salvage some ischemic tissues. Diffusion-weighted imaging based on magnetic resonance imaging (MRI) in which contrast is based on water motion can detect ischemic injury within minutes after onsets, whereas computed tomography and other imaging modalities fail to detect stroke injury for at least a few hours. Along with quantitative perfusion imaging, the perfusion-diffusion mismatch which approximates the ischemic penumbra could be imaged non-invasively. This review describes recent progresses in the development and application of multimodal MRI and image analysis techniques to study ischemic tissue at risk in experimental stroke in rats. PMID:24323751

  5. Experimental Determination of Ramsey Numbers

    NASA Astrophysics Data System (ADS)

    Bian, Zhengbing; Chudak, Fabian; Macready, William G.; Clark, Lane; Gaitan, Frank

    2013-09-01

    Ramsey theory is a highly active research area in mathematics that studies the emergence of order in large disordered structures. Ramsey numbers mark the threshold at which order first appears and are extremely difficult to calculate due to their explosive rate of growth. Recently, an algorithm that can be implemented using adiabatic quantum evolution has been proposed that calculates the two-color Ramsey numbers R(m,n). Here we present results of an experimental implementation of this algorithm and show that it correctly determines the Ramsey numbers R(3,3) and R(m,2) for 4≤m≤8. The R(8,2) computation used 84 qubits of which 28 were computational qubits. This computation is the largest experimental implementation of a scientifically meaningful adiabatic evolution algorithm that has been done to date.

  6. Experimental determination of Ramsey numbers.

    PubMed

    Bian, Zhengbing; Chudak, Fabian; Macready, William G; Clark, Lane; Gaitan, Frank

    2013-09-27

    Ramsey theory is a highly active research area in mathematics that studies the emergence of order in large disordered structures. Ramsey numbers mark the threshold at which order first appears and are extremely difficult to calculate due to their explosive rate of growth. Recently, an algorithm that can be implemented using adiabatic quantum evolution has been proposed that calculates the two-color Ramsey numbers R(m,n). Here we present results of an experimental implementation of this algorithm and show that it correctly determines the Ramsey numbers R(3,3) and R(m,2) for 4≤m≤8. The R(8,2) computation used 84 qubits of which 28 were computational qubits. This computation is the largest experimental implementation of a scientifically meaningful adiabatic evolution algorithm that has been done to date.

  7. Experimental Mathematics and Mathematical Physics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Broadhurst, David; Zudilin, Wadim

    2009-06-26

    One of the most effective techniques of experimental mathematics is to compute mathematical entities such as integrals, series or limits to high precision, then attempt to recognize the resulting numerical values. Recently these techniques have been applied with great success to problems in mathematical physics. Notable among these applications are the identification of some key multi-dimensional integrals that arise in Ising theory, quantum field theory and in magnetic spin theory.

  8. Elements of Bayesian experimental design

    SciTech Connect

    Sivia, D.S.

    1997-09-01

    We consider some elements of the Bayesian approach that are important for optimal experimental design. While the underlying principles used are very general, and are explained in detail in a recent tutorial text, they are applied here to the specific case of characterising the inferential value of different resolution peakshapes. This particular issue was considered earlier by Silver, Sivia and Pynn (1989, 1990a, 1990b), and the following presentation confirms and extends the conclusions of their analysis.

  9. Experimental Equipment for Powder Processing

    DTIC Science & Technology

    2009-08-20

    1 Final Report Experimental Equipment for Powder Processing Contract Number FA9550-06- 1 -0417 Patrick Kwon...Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour...subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1 . REPORT DATE

  10. Data archiving in experimental physics

    SciTech Connect

    Dalesio, L.R.; Watson, W. III; Bickley, M. |; Clausen, M. |

    1998-07-01

    In experimental physics, data is archived from a wide variety of sources and used for a wide variety of purposes. In each of these environments, trade-offs are made between data storage rate, data availability, and retrieval rate. This paper presents archive alternatives in EPICS, the overall archiver design and details on the data collection and retrieval requirements, performance studies, design choices, design alternatives, and measurements made on the beta version of the archiver.

  11. Experimental data confronts nuclear structure

    SciTech Connect

    Garrett, J.D.

    1988-01-01

    The physical content of experimental data for a variety of excitation energies and angular momenta is summarized. The specific nuclear structure questions which these data address are considered. The specific regions discussed are: low-spin data near the particle separation thresholds; low-spin data at intermediate excitation energies; high-spin, near-yrast data and high-spin data at larger excitation energies. 63 refs., 14 figs., 1 tab.

  12. Nonisothermal hydrologic transport experimental plan

    SciTech Connect

    Rasmussen, T.C.; Evans, D.D.

    1992-09-01

    A field heater experimental plan is presented for investigating hydrologic transport processes in unsaturated fractured rock related to the disposal of high-level radioactive waste (HLW) in an underground repository. The experimental plan provides a methodology for obtaining data required for evaluating conceptual and computer models related to HLW isolation in an environment where significant heat energy is produced. Coupled-process models are currently limited by the lack of validation data appropriate for field scales that incorporate relevant transport processes. Presented in this document is a discussion of previous nonisothermal experiments. Processes expected to dominate heat-driven liquid, vapor, gas, and solute flow during the experiment are explained, and the conceptual model for nonisothermal flow and transport in unsaturated, fractured rock is described. Of particular concern is the ability to confirm the hypothesized conceptual model specifically, the establishment of higher water saturation zones within the host rock around the heat source, and the establishment of countercurrent flow conditions within the host rock near the heat source. Field experimental plans are presented using the Apache Leap Tuff Site to illustrate the implementation of the proposed methodology. Both small-scale preliminary experiments and a long-term experiment are described.

  13. National Ignition Facility: Experimental plan

    NASA Astrophysics Data System (ADS)

    1994-05-01

    As part of the Conceptual Design Report (CDR) for the National Ignition Facility (NIF), scientists from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), the University of Rochester's Laboratory for Laser Energetics (UR/LLE), and EG&G formed an NIF Target Diagnostics Working Group. The purpose of the Target Diagnostics Working Group is to prepare conceptual designs of target diagnostics for inclusion in the facility CDR and to determine how these specifications impact the CDR. To accomplish this, a subgroup has directed its efforts at constructing an approximate experimental plan for the ignition campaign of the NIF CDR. The results of this effort are contained in this document, the Experimental Plan for achieving fusion ignition in the NIF. This group initially concentrated on the flow-down requirements of the experimental campaign leading to ignition, which will dominate the initial efforts of the NIF. It is envisaged, however, that before ignition, there will be parallel campaigns supporting weapons physics, weapons effects, and other research. This plan was developed by analyzing the sequence of activities required to finally fire the laser at the level of power and precision necessary to achieve the conditions of an ignition hohlraum target, and to then use our experience in activating and running Nova experiments to estimate the rate of completing these activities.

  14. The philosophy of scientific experimentation: a review.

    PubMed

    Radder, Hans

    2009-10-29

    Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science.

  15. The philosophy of scientific experimentation: a review

    PubMed Central

    2009-01-01

    Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science. PMID:20098589

  16. Experimental Plasma Research project summaries

    SciTech Connect

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  17. Engine Combustion Network Experimental Data

    DOE Data Explorer

    Maintained by the Engine Combustion Department of Sandia National Laboratories, data currently available on the website includes reacting and non-reacting sprays in a constant-volume chamber at conditions typical of diesel combustion. The data are useful for model development and validation because of the well-defined boundary conditions and the wide range of conditions employed. A search utility displays data based on experimental conditions such as ambient temperature, ambient density, injection pressure, nozzle size, fuel, etc. Experiment-related visualizations are also available. (Specialized Interface)

  18. Experimental study of vortex diffusers

    SciTech Connect

    Shakerin, S.; Miller, P.L.

    1995-11-01

    This report documents experimental research performed on vortex diffusers used in ventilation and air-conditioning systems. The main objectives of the research were (1) to study the flow characteristics of isothermal jets issuing from vortex diffusers, (2) to compare the vortex diffuser`s performance with that of a conventional diffuser, and (3) to prepare a report that disseminates the results to the designers of ventilation and air-conditioning systems. The researchers considered three diffusers: a conventional round ceiling diffuser and two different styles of vortex diffusers. Overall, the vortex diffusers create slightly more induction of ambient air in comparison to the conventional diffuser.

  19. Experimental Cryosurgery Investigations In Vivo

    PubMed Central

    Gage, A.A.; Baust, J.M.; Baust, J.G.

    2009-01-01

    Cryosurgery is the use of freezing temperatures to elicit an ablative response in a targeted tissue. This review provides a global overview of experimentation in vivo which has been the basis of advancement of this widely applied therapeutic option. The cellular and tissue-related events that underlie the mechanisms of destruction, including direct cell injury (cryolysis), vascular stasis, apoptosis and necrosis, are described and are related to the optimal methods of technique of freezing to achieve efficacious therapy. In vivo experiments with major organs, including wound healing, the putative immunological response following thawing, and the use of cryoadjunctive strategies to enhance cancer cell sensitivity to freezing, are described. PMID:19833119

  20. Experimental quantum multiparty communication protocols

    NASA Astrophysics Data System (ADS)

    Smania, Massimiliano; Elhassan, Ashraf M.; Tavakoli, Armin; Bourennane, Mohamed

    2016-06-01

    Quantum information science breaks limitations of conventional information transfer, cryptography and computation by using quantum superpositions or entanglement as resources for information processing. Here we report on the experimental realisation of three-party quantum communication protocols using single three-level quantum system (qutrit) communication: secret-sharing, detectable Byzantine agreement and communication complexity reduction for a three-valued function. We have implemented these three schemes using the same optical fibre interferometric setup. Our realisation is easily scalable without compromising on detection efficiency or generating extremely complex many-particle entangled states.

  1. Experimental studies of glass refining

    NASA Technical Reports Server (NTRS)

    Subramanian, R. S.; Cole, R.; Kondos, P.

    1984-01-01

    The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.

  2. Experimental telemanipulation in endoscopic surgery.

    PubMed

    Schurr, M O; Breitwieser, H; Melzer, A; Kunert, W; Schmitt, M; Voges, U; Buess, G

    1996-06-01

    Today's rigid endoscopic instruments limit the intracorporeal mobility of the surgical tool and are a severe impediment for the further spread of endoscopic techniques in operative medicine. Since 1992 flexible, steerable instruments with additional links for pivoting and rotating the tip have been developed and experimentally evaluated. The latest versions of this series of instruments are equipped with electromotors for better handling. The next aim in this development is a fully mobile telemanipulator with six motion axes dedicated to use in endoscopic surgery. Its first tests are planned for 1995. For successful operation of an electric telemanipulator, the man-machine interface (MMI) is of cardinal importance. For the definition of surgical requirements for the MMI, a conventional master-slave manipulator designed for technical application was modified for use in guiding a laparoscopic instrument. Master and slave sites of the system were 1.3 km apart and linked by means of a fiber-optic cable. Using this modified telepresence system, remote laparoscopic cholecystectomy was feasible in a phantom model. In a standardized test series using a test parcours, different parameters of the control system were modified, and their influence on the execution time of the parcours tasks was recorded. Well-suited parameter configurations were found and allowed experimental verification and completion of the important aspects of our concepts for development of an endoscopic manipulator MMI.

  3. Experimental evolution in biofilm populations

    PubMed Central

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  4. Experimental models of developmental hypothyroidism.

    PubMed

    Argumedo, G S; Sanz, C R; Olguín, H J

    2012-02-01

    Hypothyroidism is a systemic disease resulting from either thyroid gland's anatomical and functional absence or lack of hypophyseal stimulation, both of which can lead to deficiency in thyroid hormone (TH) production. TH is essential for human and animal development, growth, and function of multiple organs. Children with deficient TH can develop alterations in central nervous system (CNS), striated muscle, bone tissue, liver, bone marrow, and cardiorespiratory system. Among the clinical outlook are signs like breathing difficulty, cardiac insufficiency, dysphagia, and repeated bronchial aspiration, constipation, muscle weakness, cognitive alterations, cochlear dysfunction, reduced height, defects in temperature regulation, anaemia, jaundice, susceptibility to infection, and others. Experimental and clinical studies have shown that TH is very essential for normal brain development. Other research work based on mice pointed out that a reduced level of TH in pregnant mother leads to congenital hypothyroidism in animal models and it is associated with mental retardation, deep neurologic deficiency that impacts on cognitive, learning, and memory functions. The principal experimental model studies that have focused on hypothyroidism are reviewed in this study. This is important on considering the fact that almost all animal species require thyroid hormones for their metabolism.

  5. Experimental results on evaporation waves

    NASA Astrophysics Data System (ADS)

    Grana Otero, Jose; Parra Fabian, Ignacio

    2010-11-01

    A liquid contained in a vertical glass tube is suddenly depressurized from a high initial pressure down to one for which the stable state is vapour, so vaporization sets off at the free surface. For large enough evaporation rates, the planar vapour-liquid interface is Darrieus-Landau unstable [1], leading to the interface surface rippling close to the instability threshold. Further increasing the initial to final pressure ratio brings about evaporation waves [2,3], in which a highly corrugated front propagates downwards into the liquid. A new experimental method is presented as well as some experimental results obtained by tracking the evolution of the front with a high speed camera. In addition, a number of new phenomena related to the dynamics of bubbles growth at the walls has been uncovered. In particular, a new mode of propagation of the evaporation front is found. In this mode the front originates from below the interface, so the propagation is upwards against gravity with a curved but smooth front.[4pt] [1] F. J. Higuera, Phys. Fluids, V. 30, 679 (1987).[0pt] [2] J.E.Shepherd and B.Sturtevant, J.Fluid Mech., V.121,379 (1982).[0pt] [3] P.Reinke and G.Yadigaroglu, Int.J.Multiph. Flow, V.27,1487 (2001).

  6. X-38 Experimental Controls Laws

    NASA Technical Reports Server (NTRS)

    Munday, Steve; Estes, Jay; Bordano, Aldo J.

    2000-01-01

    X-38 Experimental Control Laws X-38 is a NASA JSC/DFRC experimental flight test program developing a series of prototypes for an International Space Station (ISS) Crew Return Vehicle, often called an ISS "lifeboat." X- 38 Vehicle 132 Free Flight 3, currently scheduled for the end of this month, will be the first flight test of a modem FCS architecture called Multi-Application Control-Honeywell (MACH), originally developed by the Honeywell Technology Center. MACH wraps classical P&I outer attitude loops around a modem dynamic inversion attitude rate loop. The dynamic inversion process requires that the flight computer have an onboard aircraft model of expected vehicle dynamics based upon the aerodynamic database. Dynamic inversion is computationally intensive, so some timing modifications were made to implement MACH on the slower flight computers of the subsonic test vehicles. In addition to linear stability margin analyses and high fidelity 6-DOF simulation, hardware-in-the-loop testing is used to verify the implementation of MACH and its robustness to aerodynamic and environmental uncertainties and disturbances.

  7. [Experimental models of acute pancreatitis].

    PubMed

    Ceranowicz, Piotr; Cieszkowski, Jakub; Warzecha, Zygmunt; Dembiński, Artur

    2015-02-21

    Acute pancreatitis is a severe disease with high mortality. Clinical studies can bring some data about etiology, pathogenesis and the course of acute pancreatitis. However, studies concerning early events of this disease and the new concepts of treatment cannot be performed on humans, due to ethical reasons. Animal models of acute pancreatitis have been developed to solve this problem. This review presents currently used experimental models of acute pancreatitis, their properties and clinical relevance. Experimental models of acute pancreatitis can be divided into in vivo (non-invasive and invasive) and ex vivo models. The onset, development, severity and extent of acute pancreatitis, as well as the mortality, vary considerably between these different models. Animal models reproducibly produce mild, moderate or severe acute pancreatitis. One of the most commonly used models of acute pancreatitis is created by administration of supramaximal doses of cerulein, an analog of cholecystokinin. This model produces acute mild edematous pancreatitis in rats, whereas administration of cerulein in mice leads to the development of acute necrotizing pancreatitis. Acute pancreatitis evoked by retrograde administration of sodium taurocholate into the pancreatic duct is the most often used model of acute severe necrotizing pancreatitis in rats. Ex vivo models allow to eliminate the influence of hormonal and nervous factors on the development of acute pancreatitis.

  8. Animal husbandry and experimental design.

    PubMed

    Nevalainen, Timo

    2014-01-01

    If the scientist needs to contact the animal facility after any study to inquire about husbandry details, this represents a lost opportunity, which can ultimately interfere with the study results and their interpretation. There is a clear tendency for authors to describe methodological procedures down to the smallest detail, but at the same time to provide minimal information on animals and their husbandry. Controlling all major variables as far as possible is the key issue when establishing an experimental design. The other common mechanism affecting study results is a change in the variation. Factors causing bias or variation changes are also detectable within husbandry. Our lives and the lives of animals are governed by cycles: the seasons, the reproductive cycle, the weekend-working days, the cage change/room sanitation cycle, and the diurnal rhythm. Some of these may be attributable to routine husbandry, and the rest are cycles, which may be affected by husbandry procedures. Other issues to be considered are consequences of in-house transport, restrictions caused by caging, randomization of cage location, the physical environment inside the cage, the acoustic environment audible to animals, olfactory environment, materials in the cage, cage complexity, feeding regimens, kinship, and humans. Laboratory animal husbandry issues are an integral but underappreciated part of investigators' experimental design, which if ignored can cause major interference with the results. All researchers should familiarize themselves with the current routine animal care of the facility serving them, including their capabilities for the monitoring of biological and physicochemical environment.

  9. SAA drift:experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Kudela, K.; Romashova, V. V.; Drozdov, A. Yu.

    According to the paleomagnetic analysis there are variations of Earth's magnetic field connected with magnetic momentum changing. Besides these variations affects on the trapped belt South Atlantic Anomaly (SAA) location. Indeed different observations including Space Shuttle short-time flights approved the existence SAA westward drift with speed 0.1-1.0 (deg/year) and northward drift with speed approximately 0.1 (deg/year). In this work we present the analysis of experimental results obtained in SINP MSU in 1972-2003 from different satellites. There were analyzed the fluxes of protons with energy > 50 MeV, gamma quanta with energy > 500 keV and neutrons with energy 0.1-1.0 MeV in SAA area and their maxima location. The data about fluxes were obtained onboard the orbital stations ``Salut-6'' (1979), MIR (1991, 1998) and ISS (2003) by the identical experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact of the SAA westward drift. Moreover the same analysis of maximum flux location of electrons with hundreds keV energy (satellites ``Kosmos-484'' (1972), ``Interkosmos-17'' (1977) and ``Activny'' (``Interkosmos-24'', 1991)) confirmed not only the SAA westward drift but northward drift also.

  10. Optimisation des dimensions d'un micromoteur électrostatique à l'aide d'une modélisation analytique du couple statique

    NASA Astrophysics Data System (ADS)

    Dufour, Isabelle; Sarraute, Emmanuel; Abbas, Ahmed; Allano, Sylvain

    1995-12-01

    Since electrostatic motors require very high voltages and do not exert great efforts on the usual dimensional scale, their design and optimisation are not well-known. But on the millimeter and micrometer scales, this kind of motor seems to present interesting qualities. The optimisation of electrostatic micromotors is generally based on the use of numerical finite element methods. Because of the numerous possible geometrical combinations, this type of optimisation takes a lot of time and must be reperformed for each application. In this paper, we present an optimisation of variable capacitance motors based solely on an analytical model of the stator/rotor capacity. For each application, this model allows determining the optimal geometrical dimensions of the electrostatic micromotor depending on the fabrication process used. Puisque les moteurs électrostatiques nécessitent de très hautes tensions d'alimentation et ne développent que très peu d'efforts dans les dimensions usuelles, leur dimensionnement et optimisation ont été peu étudiés. Ils sont maintenant utilisés dans les faibles dimensions (micromoteurs) et leur dimensionnement est en général basé sur l'utilisation de simulation numérique utilisant des codes de calcul par éléments finis. Mais, à cause des nombreuses combinaisons géométriques possibles, ce type d'optimisation nécessite beaucoup de temps de calcul et doit être renouvelé pour chaque application en fonction du cahier des charges. Dans cet article, nous présentons une optimisation des moteurs électrostatiques à réluctance diélectrique variable à excitation radiale basée uniquement sur une modélisation analytique de l'évolution de la capacité stator/rotor. A partir d'un cahier des charges fixé et des limites du procédé de fabrication utilisé, cette optimisation permet de dimensionner le micromoteur délivrant un couple moyen maximum et une ondulation de couple minimale.

  11. Experimental stress remagnetization of magnetite

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.

    1996-09-01

    Pseudo-single-domain (PSD) and multidomain (MD) magnetite grains remagnetize in weak magnetic field (30 μT) during experimental triaxial deformation. The magnetite is supported in a calcite-cement matrix. Minor remagnetization occurs with hydrostatic stress of 100 MPa. Significant remagnetization requires hydrostatic pressure of 150 MPa with differential stress of ≥5 MPa superposed on the sample. Intergranular differential stresses must be much higher due to amplification at grain asperities. Stress remagnetization does not need chemical or thermal energy. New components of magnetic remanence are added parallel to the remagnetizing field. However, this only happens in grains or parts of grains with coercivities of remanence < 15 and > 60 mT. Grains with coercivities of 20-55 mT remember the primary magnetization and are not stress magnetized. These coercivity limits do not depend on the differential stress or strain rate of the experiment. The spatial distribution of vector components of remanence was isolated by AF demagnetization. After deforming a magnetized sample, the components of remanence spread along a partial great circle between the initial remanence and the direction of the remagnetizing field. The directions of the original magnetization and the remagnetizing field are the only factors controlling the course of the remagnetization path. Triaxial deformation shortened these samples by < 17%. Thus, grain rotation fails to explain the changes in directions of magnetism. The remagnetization is attributed to the low field during stress deflection of domain walls that were possibly locked in place by deformation features. If the experimental results are transferable to nature, it is possible that a pulse of excess crustal stress > 25 MPa could partially remagnetize low-dislocation-density magnetite. The experiments show that the directions of the remagnetizing field and the primary magnetization are the only variables that affect the demagnetization

  12. The ethics of animal experimentation.

    PubMed

    Lane-Petter, W

    1976-09-01

    Animal experimentation arouses great emotion in many people, perhaps more especially in Britain, and this has increased as more sophisticated medical and non-medical animal experiments are demanded by modern research. The Cruelty to Animals Act of 1876 is the only legal regulation of experiments in animals, and many of its clauses are ambiguous. So in 1963 a committee of enquiry - the Littlewood Committee - was set up. Dr Lane-Petter examines the emotional and factual background to the enquiry, and discusses in an ethical context the usefulness and positive advantages of animal experiments compared with those of possible substitutes and in some detail three of the questions left unanswered by the Littlewood Committee.

  13. Experimental models of hepatocellular carcinoma☆

    PubMed Central

    Newell, Philippa; Villanueva, Augusto; Friedman, Scott L.; Koike, Kazuhiko; Llovet, Josep M.

    2010-01-01

    Hepatocellular carcinoma (HCC) is a common and deadly cancer whose pathogenesis is incompletely understood. Comparative genomic studies from human HCC samples have classified HCCs into different molecular subgroups; yet, the unifying feature of this tumor is its propensity to arise upon a background of inflammation and fibrosis. This review seeks to analyze the available experimental models in HCC research and to correlate data from human populations with them in order to consolidate our efforts to date, as it is increasingly clear that different models will be required to mimic different subclasses of the neoplasm. These models will be instrumental in the evaluation of compounds targeting specific molecular pathways in future preclinical studies. PMID:18314222

  14. Experimental applications of smart composites

    NASA Astrophysics Data System (ADS)

    Kalamkarov, Alexander L.; Yang, Qiang; MacDonald, Douglas O.; Westhaver, Paul A. D.

    1997-03-01

    The issues of fabrication, evaluation and experimental testing of smart composites are discussed. The technology for the fabrication of fiber reinforced polymer composites with embedded fiber optic sensors is developed. Smart composites are produced by a custom built pultruder. It is shown that the mechanical properties of pultruded carbon reinforced composites with and without optical fiber are superior to that of pultruded glass analogue. The embedded optical fibers do not have significant effect on the tensile properties of pultruded FRP, but they deteriorate the shear strength of composites. Polyimide coating on optical fiber results in a good interface between optical fiber and host material; whereas acrylate coating cannot withstand the high production temperature and causes sever debonding of optical fiber and resin. The specific application in view is the use of smart reinforcements for innovative concrete structures.

  15. Experimental contextuality in classical light

    PubMed Central

    Li, Tao; Zeng, Qiang; Song, Xinbing; Zhang, Xiangdong

    2017-01-01

    The Klyachko, Can, Binicioglu, and Shumovsky (KCBS) inequality is an important contextuality inequality in three-level system, which has been demonstrated experimentally by using quantum states. Using the path and polarization degrees of freedom of classical optics fields, we have constructed the classical trit (cetrit), tested the KCBS inequality and its geometrical form (Wright’s inequality) in this work. The projection measurement has been implemented, the clear violations of the KCBS inequality and its geometrical form have been observed. This means that the contextuality inequality, which is commonly used in test of the conflict between quantum theory and noncontextual realism, may be used as a quantitative tool in classical optical coherence to describe correlation characteristics of the classical fields. PMID:28291227

  16. Experimental quantum computing without entanglement.

    PubMed

    Lanyon, B P; Barbieri, M; Almeida, M P; White, A G

    2008-11-14

    Deterministic quantum computation with one pure qubit (DQC1) is an efficient model of computation that uses highly mixed states. Unlike pure-state models, its power is not derived from the generation of a large amount of entanglement. Instead it has been proposed that other nonclassical correlations are responsible for the computational speedup, and that these can be captured by the quantum discord. In this Letter we implement DQC1 in an all-optical architecture, and experimentally observe the generated correlations. We find no entanglement, but large amounts of quantum discord-except in three cases where an efficient classical simulation is always possible. Our results show that even fully separable, highly mixed, states can contain intrinsically quantum mechanical correlations and that these could offer a valuable resource for quantum information technologies.

  17. VENUS-2 Experimental Benchmark Analysis

    SciTech Connect

    Pavlovichev, A.M.

    2001-09-28

    The VENUS critical facility is a zero power reactor located at SCK-CEN, Mol, Belgium, which for the VENUS-2 experiment utilized a mixed-oxide core with near-weapons-grade plutonium. In addition to the VENUS-2 Core, additional computational variants based on each type of fuel cycle VENUS-2 core (3.3 wt. % UO{sub 2}, 4.0 wt. % UO{sub 2}, and 2.0/2.7 wt.% MOX) were also calculated. The VENUS-2 critical configuration and cell variants have been calculated with MCU-REA, which is a continuous energy Monte Carlo code system developed at Russian Research Center ''Kurchatov Institute'' and is used extensively in the Fissile Materials Disposition Program. The calculations resulted in a k{sub eff} of 0.99652 {+-} 0.00025 and relative pin powers within 2% for UO{sub 2} pins and 3% for MOX pins of the experimental values.

  18. Experimental Gamma-Ray Astronomy

    NASA Astrophysics Data System (ADS)

    Paneque, David

    2012-07-01

    Our knowledge of the γ-ray sky has dramatically changed due to the advent of the new ground-based Imaging Atmospheric Cherenkov Telescopes (H.E.S.S., MAGIC and VEPJTAS) and the satellite-borne instruments (AGILE and Fermi). These facilities boosted the number of γ-ray sources by one order of magnitude in the last 6 years, providing us with about 2000 sources detected above 100 MeV (from space) and about 100 sources detected above 100 GeV (from the ground). The combination of this large leap in experimental capabilities together with the fact that the Universe is still quite unexplored at these extreme energies is evidence of a large scientific discovery potential that will surely make the decade 2010-2020 a golden age for γ-ray astronomy. In this manuscript I provide a subjective review of some of the most exciting observations from this rapidly evolving field during the last two years.

  19. CHLORIDE RETENTION IN EXPERIMENTAL HYDRONEPHROSIS

    PubMed Central

    Keith, Norman M.; Pulford, D. Schuyler

    1923-01-01

    1. In acute experimental hydronephrosis chloride retention occurs as well as retention of water, urea, and phenolsulfonephthalein. 2. If both water and chlorides are retained there may be no appreciable rise in the plasma chloride content. 3. When chlorides are retained, but not water, the chloride content of the plasma rises strikingly. 4. After the removal of the ureteral obstruction in acute hydronephrosis all renal functions, water, urea, and chloride excretion, may be rapidly restored in equal degree, or the chlorides may be retained temporarily while there is free excretion of water and urea. 5. In chronic hydronephrosis adequate daily excretion of urea and chlorides may be maintained by a compensatory polyuria. 6. Chloride retention or an abnormal chloride excretion may occur in certain renal lesions when there is no change in the urea, phenolsulfonephthalein, or water excretion. PMID:19868720

  20. Communications satellites - The experimental years

    NASA Technical Reports Server (NTRS)

    Edelson, B. I.

    1983-01-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  1. A device for experimental radiosurgery.

    PubMed

    Bova, F; Spiegelmann, R; Friedman, W A

    1991-01-01

    As radiosurgery evolves into a widely available treatment modality for a variety of intracranial lesions, the need for basic research concerning the radiobiology of high-dose single-fraction ionizing radiation becomes crucial. A device especially designed for experimental radiosurgery in the cat is described. It incorporates basic parts of the Kopf stereotactic frame for accurate target positioning. A motorized pendular movement of the machine is used to describe a radiation arc, while the radiation source (either a linear accelerator or a cobalt machine) remains stationary. The pathway of the different radiation arcs is modified by rotation of the animal platform around the machine isocenter. Mechanical accuracy tests have shown a maximal alignment error of 0.15 mm, comparing favorably with that reported for modern clinical radiosurgical systems.

  2. Experimental computation with oscillatory integrals

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-06-26

    A previous study by one of the present authors, together with D. Borwein and I. Leonard [8], studied the asymptotic behavior of the p-norm of the sinc function: sinc(x) = (sin x)/x and along the way looked at closed forms for integer values of p. In this study we address these integrals with the tools of experimental mathematics, namely by computing their numerical values to high precision, both as a challenge in itself, and also in an attempt to recognize the numerical values as closed-form constants. With this approach, we are able to reproduce several of the results of [8] and to find new results, both numeric and analytic, that go beyond the previous study.

  3. Experimental Internet Environment Software Development

    NASA Technical Reports Server (NTRS)

    Maddux, Gary A.

    1998-01-01

    Geographically distributed project teams need an Internet based collaborative work environment or "Intranet." The Virtual Research Center (VRC) is an experimental Intranet server that combines several services such as desktop conferencing, file archives, on-line publishing, and security. Using the World Wide Web (WWW) as a shared space paradigm, the Graphical User Interface (GUI) presents users with images of a lunar colony. Each project has a wing of the colony and each wing has a conference room, library, laboratory, and mail station. In FY95, the VRC development team proved the feasibility of this shared space concept by building a prototype using a Netscape commerce server and several public domain programs. Successful demonstrations of the prototype resulted in approval for a second phase. Phase 2, documented by this report, will produce a seamlessly integrated environment by introducing new technologies such as Java and Adobe Web Links to replace less efficient interface software.

  4. Experimental compressive phase space tomography

    PubMed Central

    Tian, Lei; Lee, Justin; Oh, Se Baek; Barbastathis, George

    2012-01-01

    Phase space tomography estimates correlation functions entirely from snapshots in the evolution of the wave function along a time or space variable. In contrast, traditional interferometric methods require measurement of multiple two–point correlations. However, as in every tomographic formulation, undersampling poses a severe limitation. Here we present the first, to our knowledge, experimental demonstration of compressive reconstruction of the classical optical correlation function, i.e. the mutual intensity function. Our compressive algorithm makes explicit use of the physically justifiable assumption of a low–entropy source (or state.) Since the source was directly accessible in our classical experiment, we were able to compare the compressive estimate of the mutual intensity to an independent ground–truth estimate from the van Cittert–Zernike theorem and verify substantial quantitative improvements in the reconstruction. PMID:22513541

  5. Experimental Investigation of Microstructured Evaporators

    NASA Astrophysics Data System (ADS)

    Wibel, W.; Westermann, S.; Maikowske, S.; Brandner, J. J.

    2012-11-01

    Microfluidic devices have become more and more popular over the last decades [1]. Cooling is a topic where microstructures offer significant advantages compared to conventional techniques due the much higher possible surface to volume ratios and short heat transfer lengths. By evaporating of a fluid in microchannels, compact, fast and powerful cooling devices become possible [2]. Experimental results for different designs of microstructured evaporators are presented here. They have been obtained either using water as evaporating coolant or the refrigerant R134a (Tetrafluoroethane). A new microstructured evaporator design consisting of bended microchannels instead of straight channels for a better performance is shown and compared to previous results [2] for the evaporation of R134a in straight microchannels.

  6. An experimental superconducting helical undulator

    SciTech Connect

    Caspi, S.; Taylor, C.

    1995-12-31

    Improvements in the technology of superconducting magnets for high energy physics and recent advancements in SC materials with the artificial pinning centers (APC){sup 2}, have made a bifilar helical SC device an attractive candidate for a single-pass free electron laser (FEL){sup 3}. Initial studies have suggested that a 6.5 mm inner diameter helical device, with a 27 mm period, can generate a central field of 2-2.5 Tesla. Additional studies have also suggested that with a stored energy of 300 J/m, such a device can be made self-protecting in the event of a quench. However, since the most critical area associated with high current density SC magnets is connected with quenching and training, a short experimental device will have to be built and tested. In this paper we discuss technical issues relevant to the construction of such a device, including a conceptual design, fields, and forces.

  7. 'Impulsar': Experimental and Theoretical Investigations

    SciTech Connect

    Apollonov, V. V.

    2008-04-28

    The Objective of the 'Impulsar' project is to accomplish a circle of experimental, engineering and technological works on creation of a high efficiency laser rocket engine. The project includes many organizations of the rocket industry and Academy of Sciences of Russia. High repetition rate pulse-periodic CO{sub 2} laser system project for launching will be presented. Optical system for 15 MW laser energy delivery and optical matrix of laser engine receiver will by discussed as well. Basic characteristics of the laser-based engine will be compared with theoretical predictions and important stages of further technology implementation (low frequency resonance). Relying on a wide cooperation of different branches of science and industry organizations it is very possible to use the accumulated potential for launching of nano-vehicles during the upcoming 4-5 years.

  8. Experimental models of liver fibrosis.

    PubMed

    Crespo Yanguas, Sara; Cogliati, Bruno; Willebrords, Joost; Maes, Michaël; Colle, Isabelle; van den Bossche, Bert; de Oliveira, Claudia Pinto Marques Souza; Andraus, Wellington; Alves, Venâncio Avancini; Leclercq, Isabelle; Vinken, Mathieu

    2016-05-01

    Hepatic fibrosis is a wound healing response to insults and as such affects the entire world population. In industrialized countries, the main causes of liver fibrosis include alcohol abuse, chronic hepatitis virus infection and non-alcoholic steatohepatitis. A central event in liver fibrosis is the activation of hepatic stellate cells, which is triggered by a plethora of signaling pathways. Liver fibrosis can progress into more severe stages, known as cirrhosis, when liver acini are substituted by nodules, and further to hepatocellular carcinoma. Considerable efforts are currently devoted to liver fibrosis research, not only with the goal of further elucidating the molecular mechanisms that drive this disease, but equally in view of establishing effective diagnostic and therapeutic strategies. The present paper provides a state-of-the-art overview of in vivo and in vitro models used in the field of experimental liver fibrosis research.

  9. Experimental Ten-Photon Entanglement

    NASA Astrophysics Data System (ADS)

    Wang, Xi-Lin; Chen, Luo-Kan; Li, W.; Huang, H.-L.; Liu, C.; Chen, C.; Luo, Y.-H.; Su, Z.-E.; Wu, D.; Li, Z.-D.; Lu, H.; Hu, Y.; Jiang, X.; Peng, C.-Z.; Li, L.; Liu, N.-L.; Chen, Yu-Ao; Lu, Chao-Yang; Pan, Jian-Wei

    2016-11-01

    We report the first experimental demonstration of quantum entanglement among ten spatially separated single photons. A near-optimal entangled photon-pair source was developed with simultaneously a source brightness of ˜12 MHz /W , a collection efficiency of ˜70 % , and an indistinguishability of ˜91 % between independent photons, which was used for a step-by-step engineering of multiphoton entanglement. Under a pump power of 0.57 W, the ten-photon count rate was increased by about 2 orders of magnitude compared to previous experiments, while maintaining a state fidelity sufficiently high for proving the genuine ten-particle entanglement. Our work created a state-of-the-art platform for multiphoton experiments, and enabled technologies for challenging optical quantum information tasks, such as the realization of Shor's error correction code and high-efficiency scattershot boson sampling.

  10. Experimental contextuality in classical light

    NASA Astrophysics Data System (ADS)

    Li, Tao; Zeng, Qiang; Song, Xinbing; Zhang, Xiangdong

    2017-03-01

    The Klyachko, Can, Binicioglu, and Shumovsky (KCBS) inequality is an important contextuality inequality in three-level system, which has been demonstrated experimentally by using quantum states. Using the path and polarization degrees of freedom of classical optics fields, we have constructed the classical trit (cetrit), tested the KCBS inequality and its geometrical form (Wright’s inequality) in this work. The projection measurement has been implemented, the clear violations of the KCBS inequality and its geometrical form have been observed. This means that the contextuality inequality, which is commonly used in test of the conflict between quantum theory and noncontextual realism, may be used as a quantitative tool in classical optical coherence to describe correlation characteristics of the classical fields.

  11. Experimental Ten-Photon Entanglement.

    PubMed

    Wang, Xi-Lin; Chen, Luo-Kan; Li, W; Huang, H-L; Liu, C; Chen, C; Luo, Y-H; Su, Z-E; Wu, D; Li, Z-D; Lu, H; Hu, Y; Jiang, X; Peng, C-Z; Li, L; Liu, N-L; Chen, Yu-Ao; Lu, Chao-Yang; Pan, Jian-Wei

    2016-11-18

    We report the first experimental demonstration of quantum entanglement among ten spatially separated single photons. A near-optimal entangled photon-pair source was developed with simultaneously a source brightness of ∼12  MHz/W, a collection efficiency of ∼70%, and an indistinguishability of ∼91% between independent photons, which was used for a step-by-step engineering of multiphoton entanglement. Under a pump power of 0.57 W, the ten-photon count rate was increased by about 2 orders of magnitude compared to previous experiments, while maintaining a state fidelity sufficiently high for proving the genuine ten-particle entanglement. Our work created a state-of-the-art platform for multiphoton experiments, and enabled technologies for challenging optical quantum information tasks, such as the realization of Shor's error correction code and high-efficiency scattershot boson sampling.

  12. Experimental Tests of Special Relativity

    ScienceCinema

    Roberts, Tom [Illinois Institute of Technology, Chicago, Illinois, United States

    2016-07-12

    Over the past century Special Relativity has become a cornerstone of modern physics, and its Lorentz invariance is a foundation of every current fundamental theory of physics. So it is crucial that it be thoroughly tested experimentally. The many tests of SR will be discussed, including several modern high-precision measurements. Several experiments that appear to be in conflict with SR will also be discussed, such as claims that the famous measurements of Michelson and Morley actually have a non-null result, and the similar but far more extensive measurements of Dayton Miller that 'determined the absolute motion of the earth'. But the errorbars for these old experiments are huge, and are larger than their purported signals. In short, SR has been tested extremely well and stands un-refuted today, but current thoughts about quantum gravity suggest that it might not truly be a symmetry of nature.

  13. Experimental parvovirus infection in dogs.

    PubMed Central

    Potgieter, L N; Jones, J B; Patton, C S; Webb-Martin, T A

    1981-01-01

    Five eight week old dogs were inoculated orally and intranasally with cell culture origin canine parvovirus. Three dogs became depressed and anorectic and developed a mild (one dog) to severe diarrhea five days postinfection. The remaining dogs had subclinical infections but developed a lymphopenia followed by a transient lymphocytosis. The ill dogs developed mild (one dog) to severe neutropenia and a moderate lymphopenia. One died nine days postinfection. Recovery was associated with cessation of viral excretion and with lymphocytosis and antibody production. Two of three dogs challenged intragastrically developed mild clinical signs and a moderate panleukopenia four to eight days postinfection. The pathological changes of the experimental disease were very similar to that of spontaneous disease. Bone marrow changes included a severe granulocytic and mild erythroid depletion. The pathogenesis of canine parvovirus infection is discussed. Images Fig. 4. Fig. 5. Fig. 6. PMID:7340906

  14. Experimental Autoimmune Encephalomyelitis in Marmosets.

    PubMed

    Jagessar, S Anwar; Dijkman, Karin; Dunham, Jordon; 't Hart, Bert A; Kap, Yolanda S

    2016-01-01

    Experimental autoimmune encephalomyelitis (EAE) in the common marmoset, a small-bodied Neotropical primate, is a well-known and validated animal model for multiple sclerosis (MS). This model can be used for exploratory research, i.e., investigating the pathogenic mechanisms involved in MS, and applied research, testing the efficacy of new potential drugs.In this chapter, we will describe a method to induce EAE in the marmoset. In addition, we will explain the most common immunological techniques involved in the marmoset EAE research, namely isolation of mononuclear cells (MNC) from peripheral blood and lymphoid tissue, assaying T cell proliferation by thymidine incorporation, MNC phenotyping by flow cytometry, antibody measurement by ELISA, generation of B cell lines and antigen-specific T cell lines, and assaying cytotoxic T cells.

  15. Cervical carcinoma: an experimental approach.

    PubMed

    Cowan, M E; Skinner, G R

    1988-01-01

    A mouse model system was used to investigate the preventive efficacy of a subunit herpes simplex virus (HSV) vaccine on the development of HSV induced cervical carcinoma. Ten groups of mice were vaccinated before receiving repeated intravaginal exposure to HSV-type 2 inactivated by ultraviolet irradiation. At 20 months postvaccination, neutralizing antibody activity to herpes simplex viruses was detected in the sera of the mice which had received the highest vaccine dose. Although three experimental mice and one control mouse developed cervical tumours and five mice developed preinvasive malignant changes, 87% of cervices were of normal or koilocytotic appearance on histological examination. There was therefore no evidence from this study that repeated exposure of mouse cervices to inactivated HSV-2 induced a significant incidence of preinvasive or invasive cervical carcinoma.

  16. The ethics of animal experimentation.

    PubMed Central

    Lane-Petter, W.

    1976-01-01

    Animal experimentation arouses great emotion in many people, perhaps more especially in Britain, and this has increased as more sophisticated medical and non-medical animal experiments are demanded by modern research. The Cruelty to Animals Act of 1876 is the only legal regulation of experiments in animals, and many of its clauses are ambiguous. So in 1963 a committee of enquiry - the Littlewood Committee - was set up. Dr Lane-Petter examines the emotional and factual background to the enquiry, and discusses in an ethical context the usefulness and positive advantages of animal experiments compared with those of possible substitutes and in some detail three of the questions left unanswered by the Littlewood Committee. PMID:966259

  17. Ten Problems in Experimental Mathematics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal; Weisstein, Eric

    2004-09-30

    This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.

  18. Pharmacology of human experimental anxiety.

    PubMed

    Graeff, F G; Parente, A; Del-Ben, C M; Guimarães, F S

    2003-04-01

    This review covers the effect of drugs affecting anxiety using four psychological procedures for inducing experimental anxiety applied to healthy volunteers and patients with anxiety disorders. The first is aversive conditioning of the skin conductance responses to tones. The second is simulated public speaking, which consists of speaking in front of a video camera, with anxiety being measured with psychometric scales. The third is the Stroop Color-Word test, in which words naming colors are painted in the same or in a different shade, the incongruence generating a cognitive conflict. The last test is a human version of a thoroughly studied animal model of anxiety, fear-potentiated startle, in which the eye-blink reflex to a loud noise is recorded. The evidence reviewed led to the conclusion that the aversive conditioning and potentiated startle tests are based on classical conditioning of anticipatory anxiety. Their sensitivity to benzodiazepine anxiolytics suggests that these models generate an emotional state related to generalized anxiety disorder. On the other hand, the increase in anxiety determined by simulated public speaking is resistant to benzodiazepines and sensitive to drugs affecting serotonergic neurotransmission. This pharmacological profile, together with epidemiological evidence indicating its widespread prevalence, suggests that the emotional state generated by public speaking represents a species-specific response that may be related to social phobia and panic disorder. Because of scant pharmacological data, the status of the Stroop Color-Word test remains uncertain. In spite of ethical and economic constraints, human experimental anxiety constitutes a valuable tool for the study of the pathophysiology of anxiety disorders.

  19. Disposal phase experimental program plan

    SciTech Connect

    1997-01-31

    The Waste Isolation Pilot Plant (WIPP) facility comprises surface and subsurface facilities, including a repository mined in a bedded salt formation at a depth of 2,150 feet. It has been developed to safely and permanently isolate transuranic (TRU) radioactive wastes in a deep geological disposal site. On April 12, 1996, the DOE submitted a revised Resource Conservation and Recovery Act (RCRA) Part B permit application to the New Mexico Environment Department (NMED). The DOE anticipates receiving an operating permit from the NMED; this permit is required prior to the start of disposal operations. On October 29, 1996, the DOE submitted a Compliance Certification Application (CCA) to the US Environmental Protection Agency (EPA) in accordance with the WIPP land Withdrawal Act (LWA) of 1992 (Public Law 102-579) as amended, and the requirements of Title 40 of the Code of Federal Regulations (40 CFR) Parts 191 and 194. The DOE plans to begin disposal operations at the WIPP in November 1997 following receipt of certification by the EPA. The disposal phase is expected to last for 35 years, and will include recertification activities no less than once every five years. This Disposal Phase Experimental Program (DPEP) Plan outlines the experimental program to be conducted during the first 5-year recertification period. It also forms the basis for longer-term activities to be carried out throughout the 35-year disposal phase. Once the WIPP has been shown to be in compliance with regulatory requirements, the disposal phase gives an opportunity to affirm the compliance status of the WIPP, enhance the operations of the WIPP and the national TRU system, and contribute to the resolution of national and international nuclear waste management technical needs. The WIPP is the first facility of its kind in the world. As such, it provides a unique opportunity to advance the technical state of the art for permanent disposal of long-lived radioactive wastes.

  20. Remote experimental site concept development

    NASA Astrophysics Data System (ADS)

    Casper, Thomas A.; Meyer, William; Butner, David

    1995-01-01

    Scientific research is now often conducted on large and expensive experiments that utilize collaborative efforts on a national or international scale to explore physics and engineering issues. This is particularly true for the current US magnetic fusion energy program where collaboration on existing facilities has increased in importance and will form the basis for future efforts. As fusion energy research approaches reactor conditions, the trend is towards fewer large and expensive experimental facilities, leaving many major institutions without local experiments. Since the expertise of various groups is a valuable resource, it is important to integrate these teams into an overall scientific program. To sustain continued involvement in experiments, scientists are now often required to travel frequently, or to move their families, to the new large facilities. This problem is common to many other different fields of scientific research. The next-generation tokamaks, such as the Tokamak Physics Experiment (TPX) or the International Thermonuclear Experimental Reactor (ITER), will operate in steady-state or long pulse mode and produce fluxes of fusion reaction products sufficient to activate the surrounding structures. As a direct consequence, remote operation requiring robotics and video monitoring will become necessary, with only brief and limited access to the vessel area allowed. Even the on-site control room, data acquisition facilities, and work areas will be remotely located from the experiment, isolated by large biological barriers, and connected with fiber-optics. Current planning for the ITER experiment includes a network of control room facilities to be located in the countries of the four major international partners; USA, Russian Federation, Japan, and the European Community.

  1. The 1986 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1987-01-01

    The 1986 Get Away Special (GAS) Experimenter's Symposium will provide a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium is on payloads that will be flown in the future.

  2. Experimental "evolutional machines": mathematical and experimental modeling of biological evolution

    NASA Astrophysics Data System (ADS)

    Brilkov, A. V.; Loginov, I. A.; Morozova, E. V.; Shuvaev, A. N.; Pechurkin, N. S.

    Experimentalists possess model systems of two major types for study of evolution continuous cultivation in the chemostat and long-term development in closed laboratory microecosystems with several trophic structure If evolutionary changes or transfer from one steady state to another in the result of changing qualitative properties of the system take place in such systems the main characteristics of these evolution steps can be measured By now this has not been realized from the point of view of methodology though a lot of data on the work of both types of evolutionary machines has been collected In our experiments with long-term continuous cultivation we used the bacterial strains containing in plasmids the cloned genes of bioluminescence and green fluorescent protein which expression level can be easily changed and controlled In spite of the apparent kinetic diversity of evolutionary transfers in two types of systems the general mechanisms characterizing the increase of used energy flow by populations of primer producent can be revealed at their study According to the energy approach at spontaneous transfer from one steady state to another e g in the process of microevolution competition or selection heat dissipation characterizing the rate of entropy growth should increase rather then decrease or maintain steady as usually believed The results of our observations of experimental evolution require further development of thermodynamic theory of open and closed biological systems and further study of general mechanisms of biological

  3. The '3Is' of animal experimentation.

    PubMed

    2012-05-29

    Animal experimentation in scientific research is a good thing: important, increasing and often irreplaceable. Careful experimental design and reporting are at least as important as attention to welfare in ensuring that the knowledge we gain justifies using live animals as experimental tools.

  4. Control design for the SERC experimental testbeds

    NASA Technical Reports Server (NTRS)

    Jacques, Robert; Blackwood, Gary; Macmartin, Douglas G.; How, Jonathan; Anderson, Eric

    1992-01-01

    Viewgraphs on control design for the Space Engineering Research Center experimental testbeds are presented. Topics covered include: SISO control design and results; sensor and actuator location; model identification; control design; experimental results; preliminary LAC experimental results; active vibration isolation problem statement; base flexibility coupling into isolation feedback loop; cantilever beam testbed; and closed loop results.

  5. Experimental Trichinella infection in seals.

    PubMed

    Kapel, C M O; Measures, L; Møller, L N; Forbes, L; Gajadhar, A

    2003-11-01

    The susceptibility of seals to infection with Trichinella nativa and the cold tolerant characteristics of muscle larvae in seal meat were evaluated. Two grey seals, Halichoerus grypus, were inoculated with 5000 (100 larvae/kg) T. nativa larvae and two grey seals with 50000 (1000 larvae/kg). One seal from each dose group and two control seals were killed at 5 and 10 weeks post-inoculation (p.i.). At 5 weeks p.i., infection was established in both low and high dose seals with mean larval densities of 68 and 472 larvae per gram (lpg), respectively, using eight different muscles for analyses. At 10 weeks p.i., mean larval densities were 531 and 2649 lpg, respectively, suggesting an extended persistence of intestinal worms. In seals with high larval density infections, the distribution of larvae in various muscles was uniform, but in one seal with a low larval density infection, predilection sites of larvae included muscle groups with a relative high blood flow, i.e. diaphragm, intercostal and rear flipper muscles. Trichinella-specific antibody levels, as measured by ELISA, increased during the 10 week experimental period. Infected seal muscle was stored at 5, -5 and -18 degrees C for 1, 4 and 8 weeks. Muscle larvae released from stored seal muscle by artificial digestion were inoculated into mice to assess viability and infectivity. Larvae from seal muscle 10 weeks p.i. tolerated -18 degrees C for 8 weeks but larvae from seal muscle 5 weeks p.i. tolerated only 1 week at -18 degrees C, supporting the hypothesis that freeze tolerance increases with the age of the host-parasite tissue complex. The expressed susceptibility to infection, extended production of larvae, antibody response and freeze tolerance of T. nativa in seals are new findings from the first experimental Trichinella infection in any marine mammal and suggest that pinnipeds (phocids, otariiids or walrus) may acquire Trichinella infection by scavenging even small amounts of infected tissue left by hunters or

  6. Experimental overview of axion searches

    SciTech Connect

    van Bibber, K.

    1995-06-28

    Experimental methods to search for the ``invisible axion`` (f{sub a} {much_gt} 250 GeV) are reviewed. The report focuses on the axion-photon coupling, both for laboratory experiments as well as those looking for stellar or cosmologically produced axions. The conclusion is that while the axion-photon mixing in principle would permit laboratory axion searches which are broadband in mass, in fact no such experiment could have the sensitivity to the axion, where m{sub afa} {approx} m{sub {pi}f{pi}}. The only experiments which promise to have any chance to find the axion are the microwave cavity experiments, which presume axions to constitute our galactic halo dark matter. The conversion of axions into a monochromatic microwave signal in a resonant circuit affords the experiment the extraordinary sensitivity required to see the axion, at the expense of being narrow-band in mass, i.e. a tuning experiment. Two such efforts are underway in the world.

  7. Experimental Tests Of Paleoclassical Transport

    SciTech Connect

    Callen, J D; Anderson, J K; Arlen, T C; Bateman, G; Budny, R V; Fujita, T; Greenfield, C M; Greenwald, M; Groebner, R J; Hill, D N; Hogeweij, G D; Kaye, S M; Kritz, A H; Lazarus, E A; Leonard, A C; Mahdavi, M A; McLean, H S; Osborne, T H; Pankin, A Y; Petty, C C; Sarff, J S; St. John, H E; Stacey, W M; Stutman, D; Synakowski, E J; Tritz, K

    2006-09-12

    Predictions of the recently developed paleoclassical transport model are compared with data from many toroidal plasma experiments: electron heat diffusivity in DIII-D, C-Mod and NSTX ohmic and near-ohmic plasmas; transport modeling of DIII-D ohmic-level discharges and of the RTP ECH 'stair-step' experiments with eITBs at low order rational surfaces; investigation of a strong eITB in JT-60U; H-mode Te edge pedestal properties in DIII-D; and electron heat diffusivities in non-tokamak experiments (NSTX/ST, MST/RFP, SSPX/spheromak). The radial electron heat transport predicted by the paleoclassical model is found to agree with a wide variety of ohmic-level experimental results and to set the lower limit (within a factor {approx} 2) for the radial electron heat transport in most resistive, current-carrying toroidal plasmas -- unless it is exceeded by fluctuation-induced transport, which often occurs in the edge of L-mode plasmas and when the electron temperature is high ({approx}>T{sub e}{sup crit} {approx}B{sup 2/3}{bar {alpha}}{sup 1/2} keV) because then paleoclassical transport becomes less than gyro-Bohm-level anomalous transport.

  8. Experimental high-speed network

    NASA Astrophysics Data System (ADS)

    McNeill, Kevin M.; Klein, William P.; Vercillo, Richard; Alsafadi, Yasser H.; Parra, Miguel V.; Dallas, William J.

    1993-09-01

    Many existing local area networking protocols currently applied in medical imaging were originally designed for relatively low-speed, low-volume networking. These protocols utilize small packet sizes appropriate for text based communication. Local area networks of this type typically provide raw bandwidth under 125 MHz. These older network technologies are not optimized for the low delay, high data traffic environment of a totally digital radiology department. Some current implementations use point-to-point links when greater bandwidth is required. However, the use of point-to-point communications for a total digital radiology department network presents many disadvantages. This paper describes work on an experimental multi-access local area network called XFT. The work includes the protocol specification, and the design and implementation of network interface hardware and software. The protocol specifies the Physical and Data Link layers (OSI layers 1 & 2) for a fiber-optic based token ring providing a raw bandwidth of 500 MHz. The protocol design and implementation of the XFT interface hardware includes many features to optimize image transfer and provide flexibility for additional future enhancements which include: a modular hardware design supporting easy portability to a variety of host system buses, a versatile message buffer design providing 16 MB of memory, and the capability to extend the raw bandwidth of the network to 3.0 GHz.

  9. Experimental evolution meets marine phytoplankton.

    PubMed

    Reusch, Thorsten B H; Boyd, Philip W

    2013-07-01

    Our perspective highlights potentially important links between disparate fields-biological oceanography, climate change research, and experimental evolutionary biology. We focus on one important functional group-photoautotrophic microbes (phytoplankton), which are responsible for ∼50% of global primary productivity. Global climate change currently results in the simultaneous change of several conditions such as warming, acidification, and nutrient supply. It thus has the potential to dramatically change phytoplankton physiology, community composition, and may result in adaptive evolution. Although their large population sizes, standing genetic variation, and rapid turnover time should promote swift evolutionary change, oceanographers have focussed on describing patterns of present day physiological differentiation rather than measure potential adaptation in evolution experiments, the only direct way to address whether and at which rate phytoplankton species will adapt to environmental change. Important open questions are (1) is adaptation limited by existing genetic variation or fundamental constraints? (2) Will complex ecological settings such as gradual versus abrupt environmental change influence adaptation processes? (3) How will increasing environmental variability affect the evolution of phenotypic plasticity patterns? Because marine phytoplankton species display rapid acclimation capacity (phenotypic buffering), a systematic study of reaction norms renders them particularly interesting to the evolutionary biology research community.

  10. Experimental investigation of plasmofluidic waveguides

    SciTech Connect

    Ku, Bonwoo; Kwon, Min-Suk; Shin, Jin-Soo

    2015-11-16

    Plasmofluidic waveguides are based on guiding light which is strongly confined in fluid with the assistance of a surface plasmon polariton. To realize plasmofluidic waveguides, metal-insulator-silicon-insulator-metal (MISIM) waveguides, which are hybrid plasmonic waveguides fabricated using standard complementary metal-oxide-semiconductor technology, are employed. The insulator of the MISIM waveguide is removed to form 30-nm-wide channels, and they are filled with fluid. The plasmofluidic waveguide has a subwavelength-scale mode area since its mode is strongly confined in the fluid. The waveguides are experimentally characterized for different fluids. When the refractive index of the fluid is 1.440, the plasmofluidic waveguide with 190-nm-wide silicon has propagation loss of 0.46 dB/μm; the coupling loss between it and an ordinary silicon photonic waveguide is 1.79 dB. The propagation and coupling losses may be reduced if a few fabrication-induced imperfections are removed. The plasmofluidic waveguide may pave the way to a dynamically phase-tunable ultracompact device.

  11. Compendium of Experimental Cetane Numbers

    SciTech Connect

    Yanowitz, J.; Ratcliff, M. A.; McCormick, R. L.; Taylor, J. D.; Murphy, M. J.

    2014-08-01

    This report is an updated version of the 2004 Compendium of Experimental Cetane Number Data and presents a compilation of measured cetane numbers for pure chemical compounds. It includes all available single compound cetane number data found in the scientific literature up until March 2014 as well as a number of unpublished values, most measured over the past decade at the National Renewable Energy Laboratory. This Compendium contains cetane values for 389 pure compounds, including 189 hydrocarbons and 201 oxygenates. More than 250 individual measurements are new to this version of the Compendium. For many compounds, numerous measurements are included, often collected by different researchers using different methods. Cetane number is a relative ranking of a fuel's autoignition characteristics for use in compression ignition engines; it is based on the amount of time between fuel injection and ignition, also known as ignition delay. The cetane number is typically measured either in a single-cylinder engine or a constant volume combustion chamber. Values in the previous Compendium derived from octane numbers have been removed, and replaced with a brief analysis of the correlation between cetane numbers and octane numbers. The discussion on the accuracy and precision of the most commonly used methods for measuring cetane has been expanded and the data has been annotated extensively to provide additional information that will help the reader judge the relative reliability of individual results.

  12. Experimental research control software system

    NASA Astrophysics Data System (ADS)

    Cohn, I. A.; Kovalenko, A. G.; Vystavkin, A. N.

    2014-05-01

    A software system, intended for automation of a small scale research, has been developed. The software allows one to control equipment, acquire and process data by means of simple scripts. The main purpose of that development is to increase experiment automation easiness, thus significantly reducing experimental setup automation efforts. In particular, minimal programming skills are required and supervisors have no reviewing troubles. Interactions between scripts and equipment are managed automatically, thus allowing to run multiple scripts simultaneously. Unlike well-known data acquisition commercial software systems, the control is performed by an imperative scripting language. This approach eases complex control and data acquisition algorithms implementation. A modular interface library performs interaction with external interfaces. While most widely used interfaces are already implemented, a simple framework is developed for fast implementations of new software and hardware interfaces. While the software is in continuous development with new features being implemented, it is already used in our laboratory for automation of a helium-3 cryostat control and data acquisition. The software is open source and distributed under Gnu Public License.

  13. Experimental investigations of elastohydrodynamic lubrication

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1983-01-01

    Various experimental studies of elastohydrodynamic lubrication have been reviewed. The various types of machines used in these investigations, such as the disc, two and four ball, crossed-cylinders, and crossed-axes rolling disc machine, are described. The measurement of the most important parameters, such as film shape, film thickness, pressure, temperature, and traction, is considered. Determination of the film thickness is generally the most important of these effects since it dictates the extent to which the asperities on opposing surfaces can come into contact and thus has a direct bearing on wear and fatigue failure of the contacting surfaces. Several different techniques for measuring film thickness have been described, including electrical resistance, capacitance, X-ray, optical interferometry, laser beam diffraction, strain gage, and spring dynamometer methods. An attempt has been made to describe the basic concepts and limitations of each of these techniques. These various methods have been used by individual researchers, but there is no universally acceptable technique for measuring elastohydrodynamic film thickness. Capacitance methods have provided most of the reliable data for nominal line or rectangular conjunctions, but optical interferometry has proved to be the most effective procedure for elliptical contacts. Optical interferometry has the great advantage that it reveals not only the film thickness, but also details of the film shape over the complete area of the conjunction.

  14. Experimental Volcanology: Fragmentation and Permeability

    NASA Astrophysics Data System (ADS)

    Spieler, O.

    2005-12-01

    An increasing number of scientists design new experiments to analyse processes that control the dynamics of explosive eruptions. There research is mostly coupled to numerical models and aims toward its controlling parameters. The fragmentation process, its threshold and the speed of the fragmentation wave as well as the energy consumed by the fragmentation are some hot spots of the experimental volcanology. Analysing the fragmentation behaviour of volcaniclastics as close to the natural system as possible, we found a number of physical constrains. Identifying the porosity as determining factor of the threshold, we realised that neither threshold nor the speed of the fragmentation process are solely controlled by the rock density. The later results of the shock tube type apparatus lead to the analysis of the specific surface area and permeability as direct links to textural features. Permeability analysis performed in a modified shock tube type apparatus, show two clear, distinct trends for dome rock and pyroclastic samples. The specific surface determined by Argon sorbtion (BET) as well as textural features of pumices from Campi Flegrei, Montserrat and Krakatoa (1883) give in contrary evidence of a more complex story. Large spherical, or ellipsoidal bubbles around fractured crystals prove that the high permeability of the pumice has partially developed after the fixing of the bubble size distribution. This puts up the question, if permeability measurements on pyroclastic samples reveal relevant numbers! The surface tension controlled 'self sealing' behaviour of surfaces from foaming obsidian hinders in situ measurements. Close textural investigations will have to clarify how the 'post process' samples deviate from the syneruptive conduit filling.

  15. Magnetic Launch Assist Experimental Track

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In this photograph, a futuristic spacecraft model sits atop a carrier on the Magnetic Launch Assist System, formerly known as the Magnetic Levitation (MagLev) System, experimental track at the Marshall Space Flight Center (MSFC). Engineers at MSFC have developed and tested Magnetic Launch Assist technologies that would use magnetic fields to levitate and accelerate a vehicle along a track at very high speeds. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a Magnetic Launch Assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide, and about 1.5-feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  16. Experimental Infrasound Studies in Nevada

    NASA Astrophysics Data System (ADS)

    Herrin, E. T.; Negraru, P. T.; Golden, P.; Williams, A.

    2009-12-01

    An experimental propagation study was carried out in Nevada in June 2009 on Julian days 173-177. During this field experiment we deployed 16 single channel digital infrasound recorders to monitor the munitions disposal activities near Hawthorne, NV. The sensors were deployed in a single line and placed approximately 12 km apart at distances ranging from 2 to 177 km. A four element semi-permanent infrasound array named FNIAR was installed approximately 154 km north of the detonation site in line with the individual temporary recorders. Tropospheric arrivals were observed during all days of the experiment, but during day 176 the observed arrivals had very large amplitudes. A large signal was observed at 58 km from the detonation site with amplitude as large as 4 Pascals, while at 94 km no signal was observed. At FNIAR the amplitude of the tropospheric arrival was 1 Pascal. During this day meteorological data acquired in the propagation path showed a strong jet stream to the north. On day 177 we were not able to identify tropospheric arrivals beyond 34 km, but at stations beyond 152 km we observed stratospheric arrivals. Continuous monitoring of these signals at FNIAR shows that stratospheric arrivals are the most numerous. In a two month period, from 06/15/2009 to 08/15/2009 there were 35 operational days at the Hawthorne disposal facility resulting in 212 explosions with known origin times. Based on the celerity values there were 115 explosions that have only stratospheric arrivals (celerities of 300-275 m/s), 72 explosions with both tropospheric (celerities above 330 m/s) and stratospheric arrivals, 20 explosions that were not detected and five explosions that have only tropospheric arrivals.

  17. Experimental investigation of hypersonic aerodynamics

    NASA Technical Reports Server (NTRS)

    Intrieri, Peter F.

    1988-01-01

    An extensive series of ballistic range tests were conducted at the Ames Research Center to determine precisely the aerodynamic characteristics of the Galileo entry probe vehicle. Figures and tables are presented which summarize the results of these ballistic range tests. Drag data were obtained for both a nonablated and a hypothesized ablated Galileo configuration at Mach numbers from about 0.7 to 14 and at Reynolds numbers from 1000 to 4 million. The tests were conducted in air and the experimental results were compared with available Pioneer Venus data since these two configurations are similar in geometry. The nonablated Galileo configuration was also tested with two different center-of-gravity positions to obtain values of pitching-moment-curve slope which could be used in determining values of lift and center-of-pressure location for this configuration. The results indicate that the drag characteristics of the Galileo probe are qualitatively similar to that of Pioneer Venus, however, the drag of the nonablated Galileo is about 3 percent lower at the higher Mach numbers and as much as 5 percent greater at transonic Mach numbers of about 1.0 to 1.5. Also, the drag of the hypothesized ablated configuration is about 3 percent lower than that of the nonablated configuration at the higher Mach numbers but about the same at the lower Mach numbers. Additional tests are required at Reynolds numbers of 1000, 500, and 250 to determine if the dramatic rise in drag coefficient measured for Pioneer Venus at these low Reynolds numbers also occurs for Galileo, as might be expected.

  18. [Regeneration of planarians: experimental object].

    PubMed

    Sheĭman, I M; Kreshchenko, I D

    2015-01-01

    We discuss the expediency of using invertebrates, such as flatworms and planarians, as experimental objects. Free-living planarian flatworms (phylum Platyhelminthes, class Turbellaria) are invertebrate animals in which a bilateral symmetry appears for the first time in evolution and organs and tissues form. As the highest ecological link of the food chain--predators--these animals are characterized by a set of behavioral reactions controlled by a differentiated central nervous system. Planarians have unsurpassed ability to regenerate lost or damaged body parts. Owing to the ease of their breeding and their convenience for manipulations, these animals are used to study the influence of chemical and physical factors on the processes of life, growth, and reproduction. Currently, planarians are recognized as a model for biological research in the field of regeneration, stem cell biology, study of their proliferation and differentiation, as well as the regulatory mechanisms of morphogenetic processes. The genome of the planarian Schmidtea mediterranea was fully sequenced, which opened up the opportunity to work with this object at the molecular biological level. Furthermore, planarians are used in neurobiological and toxicological studies, in studying the evolutionary aspects of centralization of the nervous system, mechanisms of muscle contraction, and in the development of new antiparasitic drugs. This review aims to demonstrate the relevance and diversity of research conducted on simple biological objects--planarians--to awider audience to show the historical continuity of these studies and their wide geographical distribution and to focus on the studies carried out in Russia, which, as a rule, are not included in the foreign reviews on planarian regeneration.

  19. Experimental Tests of Nucleation Theory

    NASA Astrophysics Data System (ADS)

    Dea, Jack Yuen

    1982-03-01

    In recent years there has been controversy surrounding experimental nucleation data that did not conform to classical nucleation theory. More recent data, however, suggest good agreement between theory and experiment. At the Desert Research Institute (DRI), it was decided to perform sensitive tests of nucleation in soluble aerosol particles using newly developed instruments and techniques. Very steady aerosol generation was accomplished with a newly developed atomizer; very high monodispersity in the sample aerosol was achieved using two electrical mobility analyzers in series; and, very fine control over the supersaturation was achieved using a newly developed CFD (Continuous Flow Diffusion) cloud chamber built for NASA for use in zero -gravity situations. The results of a series of experiments indicated that the supersaturation needs to be about 15% greater than predicted by theory. However, a mass correction, taking into account the shape of the salt particles produced data that are in excellent agreement with theory. Moreover, the relative hygroscopicity of several soluble substances and the slopes of the Kohler curves obtained agreed very well with theory. The results mean that the hygroscopicity of various substances can be rated using the Kohler curves. Calculations have been done to determine the hygroscopicity of a number of sulfate compounds. The results of these calculations indicate that under restricted conditions (aerosol diameters < 0.1 (mu)m and aerosol particles composed of either one soluble compound or one soluble compound plus an insoluble component), it is possible to distinguish apart most of the sulfate species using either the DFC cloud chamber or an instantaneous version of the CFD cloud chamber. These results point to a possible application of nucleation theory to aerosol species differentiation in the atmosphere.

  20. Epistemological Dizziness in the Psychology Laboratory: Lively Subjects, Anxious Experimenters, and Experimental Relations, 1950-1970.

    PubMed

    Morawski, Jill

    2015-09-01

    Since the demise of introspective techniques in the early twentieth century, experimental psychology has largely assumed an administrative arrangement between experimenters and subjects wherein subjects respond to experimenters' instructions and experimenters meticulously constrain that relationship through experimental controls. During the postwar era this standard arrangement came to be questioned, initiating reflections that resonated with Cold War anxieties about the nature of the subjects and the experimenters alike. Albeit relatively short lived, these interrogations of laboratory relationships gave rise to unconventional testimonies and critiques of experimental method and epistemology. Researchers voiced serious concerns about the honesty and normality of subjects, the politics of the laboratory, and their own experimental conduct. Their reflective commentaries record the intimacy of subject and experimenter relations and the plentiful cultural materials that constituted the experimental situation, revealing the permeable boundaries between laboratory and everyday life.

  1. Experimental reproduction of tsunami deposit

    NASA Astrophysics Data System (ADS)

    Yoshii, T.; Matsuyama, M.; Tanaka, S.

    2015-12-01

    in reproducing tsunami deposit and would show typical pattern of topography change and deposition caused by the tsunami incursion. The experimental method used in this study and the obtained deposition patterns will help understanding the relationship between hydraulic condition and resulting tsunami deposition.

  2. Experimental toxoplasmosis in broiler chicks.

    PubMed

    Kaneto, C N; Costa, A J; Paulillo, A C; Moraes, F R; Murakami, T O; Meireles, M V

    1997-05-01

    To evaluate chicken toxoplasmosis both as an economic and a public health subject, 84 broiler chicks of a commercial strain, 30 days old, were distributed into seven groups of 12 birds (three replications of four chicks) experimentally infected with three developing T. gondii stages of the P strain as follows: tachyzoites, intravenous (two groups: 5.0 x 10(5) and 5.0 x 10(6)), cysts, per os (two groups: 1.0 x 10(2) and 1.0 x 10(3)) and oocysts, per os (three groups: 5.0 x 10(2), 5.0 x 10(3) and 5.0 x 10(4)). Twelve chicks received only a placebo (control group). During the next 30 days the following parameters were estimated: productivity (weight gain and feed conversion), clinical signs, including rectal temperature and parasitemia (bioassay). No clinical signs suggesting toxoplasmosis were seen and no statistical differences on productivity standards were found in comparison between inoculated and control chicks. However, fowls inoculated with tachyzoites and oocysts occasionally showed hyperthermia. Some haematological changes were detected in fowls inoculated with T. gondii. Anatomo-histopathological changes were not observed. From 14 parasitemias detected, 35.7% appeared on the 5th day after inoculation and 57.1% of them resulted from oocysts inoculation. After 30-35 days all birds were slaughtered: fragments from 12 organs or tissues from each of them were subjected to artificial peptic digestion and after that injected into T. gondii antibody-free mice (IIFR). T. gondii was detected in brain (12), pancreas (five), spleen (five), retina (five), kidney (two), heart (four), proventriculus (three), liver (two), intestine (two), lung (one), and skeletal muscle (one). Similar to observations with parasitemia, from 42 T. gondii isolations, 59.5% came from chicks which had received oocysts. It can thus be inferred that the developing form, expelled by cats, is the most important for T. gondii chicken infection and that brain is the most infected organ in birds

  3. Experimental generation of volcanic lightning

    NASA Astrophysics Data System (ADS)

    Cimarelli, Corrado; Alatorre-Ibargüengoitia, Miguel; Kueppers, Ulrich; Scheu, Bettina; Dingwell, Donald B.

    2014-05-01

    the plume that emerge as the key variables in volcanic lightning generation. A proportionality between fine ash content of the jet and number of lightning strikes is also evident in our experiments. This first recorded experimental generation of volcanic lightning means that rapid progress can now be expected (under controlled laboratory conditions) in understanding electrical phenomena produced during explosive volcanic eruptions. This in turn may aid the development of lightning monitoring systems for the forecasting of volcanic ash emissions into the atmosphere. Furthermore, our experiments are significant for the investigation of self-charging mechanism of particles that are relevant for atmospheric phenomena (such as dust storms) on Earth and other planetary bodies.

  4. Mars Radiator Characterization Experimental Program

    NASA Technical Reports Server (NTRS)

    Witte, Larry C.; Hollingsworth, D. Keith

    2004-01-01

    Radiators are an enabling technology for the human exploration and development of the moon and Mars. As standard components of the heat rejection subsystem of space vehicles, radiators are used to reject waste heat to space and/or a planetary environment. They are typically large components of the thermal control system for a space vehicle or human habitation facility, and in some cases safety factors are used to oversize them when the operating environment cannot be fully characterized. Over-sizing can impose significant weight and size penalties that might be prohibitive for future missions. Radiator performance depends on the size of the radiator surface, its emittance and absorptance, the radiator temperature, the effective sky temperature surrounding the radiator, solar radiation and atmospheric irradiation levels, convection to or from the atmosphere (on Mars), and other conditions that could affect the nature of the radiator surface, such as dust accumulation. Most particularly, dust is expected to be a major contributor to the local environmental conditions on either the lunar or Martian surface. This conclusion regarding Mars is supported by measurements of dust accumulation on the Mars Sojourner Rover solar array during the Pathfinder mission. This Final Report describes a study of the effect of Martian dust accumulation on radiator performance. It is comprised of quantitative measurements of effective emittance for a range of dust accumulation levels on surfaces of known emittance under clean conditions. The test radiator coatings were Z-93P, NS-43G, and Silver Teflon (10 mil) film. The Martian dust simulant was Carbondale Red Clay. Results were obtained under vacuum conditions sufficient to reduce convection effects virtually to zero. The experiments required the development of a calorimetric apparatus that allows simultaneous measurements of the effective emittance for all the coatings at each set of experimental conditions. A method of adding dust to

  5. [Experimental antitriatomic program in Santiago].

    PubMed

    Neghme, A; Schenone, H; Villarroel, F; Rojas, A

    1991-01-01

    The rural migration to urban centers occurred since the 40s in many Latin American countries, including Santiago the capital city of Chile, originated a growing belt of premises built with light poor material (the rests of previous rural habitations, mud, pieces of timber, plastic and cardboard for walls, and cane stalks and artificial clinkstones for roofs) giving raise to many types of slums. This situation facilitated the passive transport of the different instars, including eggs, of triatomine bugs. Due to the fact that in the 1959-1960 warm seasons, the Santiago province health institutions had received an increasing reported number of triatomine bugs (Triatoma infestans) in dwellings from different periurban, even urban and rural sections of the province, the central local health authorities with the advise of the University of Chile, Department of Parasitology decided to carry out an experimental program against these vectors of Chagas' disease. The program consisted basically in an spray and thorough application of liquid forms (emulsion, suspension, solution) of 1% lindane (average > or = 500 mg per 1 m2), depending on the material of the constructions, to all the surfaces of walls, ceilings, attics and peridomiciliary structures of all the infested dwellings in a sector and those located less than 100 m around. In order to reach triatomine bugs not affected, for different reasons, in the first spraying, a second application, identical to the first was performed to the total number of premises between 30 and 120 days later. Periodical evaluations were made, and positive dwellings found and neighboring ones were sprayed again. During insecticide applications adequate protection measures for spraying workers, inhabitants, domestic animals, household goods and food were adopted. All the steps of the program were accompanied by health education activities directed to individuals, families, school teachers and community institutions, tending to motivate the

  6. Experimental Aerobraking with Venus Express

    NASA Astrophysics Data System (ADS)

    Svedhem, Hakan

    2013-10-01

    Venus Express has successfully orbited Venus in its polar 24 hour, 250km by 66000 km, orbit since April 2006 and has provided a wealth of new data from our sister planet. Approaching the end of the mission we are now planning an experimental campaign dedicated to aerobraking at altitudes down to as low as about 130km. These low pericentre passes will provide direct measurements of density, temperature, magnetic field and energetic particles in a region not accessible by other methods. Experience of operations and studies of spacecraft responses will be valuable knowledge for possible future missions that might need this techniques as a part of its nominal operations. Aerobraking was considered in the early design phase of the mission but it was fairly soon realised that the nominal mission would not need this. However, a few important design features were maintained in order to allow for this in case it should be needed at a later stage. The inherently stable geometry of the spacecraft configuration and the inclusion of a software mode for aerobraking are the two most important elements from this early design phase. An recent study by industry has determined the constraints for the spacecraft and identified several potential scenarios. The present highly elliptical orbit has as one of its inherent features a downward drift of the pericentre altitude of between 1 and 4 km/day. However, at certain times, when the Sun is in the orbital plane, this drift disappears for a period of up to two weeks. This is a very well suited time to carry out these initial experiments as it is makes operations safer and it reduces the heat input on the spacecraft as the solar panels will be edge-on towards the sun during the aerobraking. Already a number of low altitude operations have been carried out during the so called atmospheric drag campaigns. The spacecraft has then dipped down to altitudes as low as 165 km and a good characterisation of this region has been performed. This

  7. Charge of the containerless experimentation in microgravity

    NASA Technical Reports Server (NTRS)

    Lee, Mark C.

    1990-01-01

    The experimentation was undertaken to study the elimination or reduction of surface contamination for which there is adequate Earth-based technology along with the reduction of dynamic nucleation for which there a paucity of reliable data. One objective is to delineate scientific justification of the U.S. Containerless Experimentation Program in Microgravity for the next decade and beyond. Another objective is for the guidance of NASA to define the next generation of containerless experimentation instruments in microgravity.

  8. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... such machines; and (3) Use by laboratories, hospitals, medical centers, institutes, colleges, or universities, for scientific, technical, or medical research. (b) What purposes are not experimental? The...

  9. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... such machines; and (3) Use by laboratories, hospitals, medical centers, institutes, colleges, or universities, for scientific, technical, or medical research. (b) What purposes are not experimental? The...

  10. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... such machines; and (3) Use by laboratories, hospitals, medical centers, institutes, colleges, or universities, for scientific, technical, or medical research. (b) What purposes are not experimental? The...

  11. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... such machines; and (3) Use by laboratories, hospitals, medical centers, institutes, colleges, or universities, for scientific, technical, or medical research. (b) What purposes are not experimental? The...

  12. 27 CFR 40.232 - Experimental purposes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... such machines; and (3) Use by laboratories, hospitals, medical centers, institutes, colleges, or universities, for scientific, technical, or medical research. (b) What purposes are not experimental? The...

  13. The 1985 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, L. R. (Editor); Mosier, F. L. (Editor)

    1986-01-01

    The 1985 Get Away Special (GAS) Experimenter's Symposium provided a formal opportunity for GAS experimenters to share the results of their projects. The focus is on payloads that have been flown on Shuttle missions, and on GAS payloads that will be flown in the near future.

  14. A new dimension in space experimentation

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Space experimentation, cosmic origins, the long-term effects of the space environment on living things, the long-term effects of space environment on materials and hardware, seeds in space, power generation in space, experimentation with crystals, and thermal control are discussed.

  15. Optimizing Experimental Designs: Finding Hidden Treasure.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical experimental design theory, the predominant treatment in most textbooks, promotes the use of blocking designs for control of spatial variability in field studies and other situations in which there is significant variation among heterogeneity among experimental units. Many blocking design...

  16. The 1987 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Barthelme, Neal (Editor); Mosier, Frances L. (Editor)

    1988-01-01

    The 1987 Get Away Special (GAS) Experimenter's symposium provides a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium was on payloads that were flown on Shuttle missions, and on GAS payloads that will be flown in the future.

  17. Experimental Influence Coefficients and Vibration Modes

    NASA Technical Reports Server (NTRS)

    Weidman, Deene J.; Kordes, Eldon E.

    1959-01-01

    Test results are presented for both symmetrical and antisymmetrical static loading of a wing model mounted on a three-point support system. The first six free-free vibration modes were determined experimentally. A comparison is made of the symmetrical nodal patterns and frequencies with the symmetrical nodal patterns and frequencies calculated from the experimental influence coefficients.

  18. New model systems for experimental evolution.

    PubMed

    Collins, Sinéad

    2013-07-01

    Microbial experimental evolution uses a few well-characterized model systems to answer fundamental questions about how evolution works. This special section highlights novel model systems for experimental evolution, with a focus on marine model systems that can be used to understand evolutionary responses to global change in the oceans.

  19. Assessing Students' Experimentation Processes in Guided Inquiry

    ERIC Educational Resources Information Center

    Emden, Markus; Sumfleth, Elke

    2016-01-01

    In recent science education, experimentation features ever more strongly as a method of inquiry in science classes rather than as a means to illustrate phenomena. Ideas and materials to teach inquiry abound. Yet, tools for assessing students' achievement in their processes of experimentation are lacking. The present study assumes a basal,…

  20. FELIX construction status and experimental program

    SciTech Connect

    Turner, L.R.; Praeg, W.F.; Knott, M.J.; Lari, R.J.; McGhee, D.G.; Wehrle, R.B.

    1983-01-01

    FELIX (Fusion Electromagnetic Induction Experiment) is an experimental test facility being constructed at Argonne National Laboratory (ANL) for the study of electromagnetic effects in the first wall/blanket/shield (FWBS) systems of fusion reactors. The facility design, construction status, experimental program, instrumentation, and associated computer-code comparisons are described.

  1. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Experimental wine. 24.77... OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  2. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Experimental wine. 24.77... OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  3. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Experimental wine. 24.77... OF THE TREASURY ALCOHOL WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  4. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Experimental wine. 24.77... OF THE TREASURY ALCOHOL WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  5. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Experimental wine. 24.77... OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of...

  6. Quasi-Experimental Designs for Causal Inference

    ERIC Educational Resources Information Center

    Kim, Yongnam; Steiner, Peter

    2016-01-01

    When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

  7. The 1988 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1988-01-01

    The Get Away Special (GAS) Experimenter's Symposium was held to provide a formal opportunity for GAS experimenters to share the results of their projects. The focus of this symposium is on payloads that have been flown on shuttle missions and on GAS payloads that will be flown in the future. Experiment design and payload integration issues are also examined.

  8. ISABELLE. Volume 3. Experimental areas, large detectors

    SciTech Connect

    Not Available

    1981-01-01

    This section presents the papers which resulted from work in the Experimental Areas portion of the Workshop. The immediate task of the group was to address three topics. The topics were dictated by the present state of ISABELLE experimental areas construction, the possibility of a phased ISABELLE and trends in physics and detectors.

  9. Mainstreaming Caenorhabditis elegans in experimental evolution

    PubMed Central

    Gray, Jeremy C.; Cutter, Asher D.

    2014-01-01

    Experimental evolution provides a powerful manipulative tool for probing evolutionary process and mechanism. As this approach to hypothesis testing has taken purchase in biology, so too has the number of experimental systems that use it, each with its own unique strengths and weaknesses. The depth of biological knowledge about Caenorhabditis nematodes, combined with their laboratory tractability, positions them well for exploiting experimental evolution in animal systems to understand deep questions in evolution and ecology, as well as in molecular genetics and systems biology. To date, Caenorhabditis elegans and related species have proved themselves in experimental evolution studies of the process of mutation, host–pathogen coevolution, mating system evolution and life-history theory. Yet these organisms are not broadly recognized for their utility for evolution experiments and remain underexploited. Here, we outline this experimental evolution work undertaken so far in Caenorhabditis, detail simple methodological tricks that can be exploited and identify research areas that are ripe for future discovery. PMID:24430852

  10. Gaseous Sulfate Solubility in Glass: Experimental Method

    SciTech Connect

    Bliss, Mary

    2013-11-30

    Sulfate solubility in glass is a key parameter in many commercial glasses and nuclear waste glasses. This report summarizes key publications specific to sulfate solubility experimental methods and the underlying physical chemistry calculations. The published methods and experimental data are used to verify the calculations in this report and are expanded to a range of current technical interest. The calculations and experimental methods described in this report will guide several experiments on sulfate solubility and saturation for the Hanford Waste Treatment Plant Enhanced Waste Glass Models effort. There are several tables of sulfate gas equilibrium values at high temperature to guide experimental gas mixing and to achieve desired SO3 levels. This report also describes the necessary equipment and best practices to perform sulfate saturation experiments for molten glasses. Results and findings will be published when experimental work is finished and this report is validated from the data obtained.

  11. Experimental economics' inconsistent ban on deception.

    PubMed

    Hersch, Gil

    2015-08-01

    According to what I call the 'argument from public bads', if a researcher deceived subjects in the past, there is a chance that subjects will discount the information that a subsequent researcher provides, thus compromising the validity of the subsequent researcher's experiment. While this argument is taken to justify an existing informal ban on explicit deception in experimental economics, it can also apply to implicit deception, yet implicit deception is not banned and is sometimes used in experimental economics. Thus, experimental economists are being inconsistent when they appeal to the argument from public bads to justify banning explicit deception but not implicit deception.

  12. EXFOR Library of Experimental Nuclear Reaction Data

    DOE Data Explorer

    The EXFOR library contains an extensive compilation of experimental nuclear reaction data up to 1 GeV. Neutron reactions have been compiled systematically since the discovery of the neutron, while charged particle(up to carbon) and photon reactions have been covered less extensively. Files contain nuclear reaction data such as cross sections, spectra, angular distributions, polarizations, etc, along with information on experimental technique, error analysis, and applied standards. Numerous search parameters include: target, beam, product, experimental method, and even author and publication names. The library contains data from more than 20,000 experiments. (Specialized Interface)

  13. Experimental millimeter-wave satellite communications system

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshiaki; Shimada, Masaaki; Arimoto, Yoshinori; Shiomi, Tadashi; Kitazume, Susumu

    This paper describes an experimental system of millimeter-wave satellite communications via Japan's Engineering Test Satellite-VI (ETS-VI) and a plan of experiments. Two experimental missions are planned using ETS-VI millimeter-wave (43/38 GHz bands) transponder, considering the millimeter-wave characteristics such as large transmission capacity and possibility to construct a small earth station with a high gain antenna. They are a personal communication system and an inter-satellite communication system. Experimental system including the configuration and the fundamental functions of the onboard transponder and the outline of the experiments are presented.

  14. Experimental area power monitoring during shutdown

    SciTech Connect

    Pathiyil, J.

    1989-03-01

    The power consumption at the site is increasing every year and the power consumption in the fixed target beam lines is constantly changing for each run. Since we do not have an energy monitoring program in effect in the experimental areas; we are not in a position to tell whether we are using the electrical energy efficiently. The purpose of this study is to find the summer and winter base load of the three experimental areas while the beamlines are off and also to identify what kind loads are on. The most important purpose was to find the base loads in each of the big experimental halls during the shutdown.

  15. Drought Adaptation Mechanisms Should Guide Experimental Design.

    PubMed

    Gilbert, Matthew E; Medina, Viviana

    2016-08-01

    The mechanism, or hypothesis, of how a plant might be adapted to drought should strongly influence experimental design. For instance, an experiment testing for water conservation should be distinct from a damage-tolerance evaluation. We define here four new, general mechanisms for plant adaptation to drought such that experiments can be more easily designed based upon the definitions. A series of experimental methods are suggested together with appropriate physiological measurements related to the drought adaptation mechanisms. The suggestion is made that the experimental manipulation should match the rate, length, and severity of soil water deficit (SWD) necessary to test the hypothesized type of drought adaptation mechanism.

  16. Experimental Investigations of Flow past Spinning Cylinders

    NASA Astrophysics Data System (ADS)

    Carlucci, Pasquale; Buckley, Liam; Mehmedagic, Igbal; Carlucci, Donald; Thangam, Siva

    2015-11-01

    Experimental investigations of flow past spinning cylinders is presented in the context of their application and relevance to flow past projectiles. A subsonic wind tunnel is used to perform experiments on flow past spinning cylinders that are sting-mounted and oriented such that their axis of rotation is aligned with the mean flow. The experiments cover a Reynolds number range of up to 300000 and rotation numbers of up to 2 (based on cylinder diameter). The experimental validation of the tunnel characteristics and the benchmarking of the flow field in the tunnel are described. The experimental results for spinning cylinders with both rear-mounted and fore-mounted stings are presented along with available computational and experimental findings. This work was funded in part by U. S. Army ARDEC.

  17. Evapotranspiration studies for protective barriers: Experimental plans

    SciTech Connect

    Link, S.O.; Waugh, W.J.

    1989-11-01

    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs.

  18. Multiple sclerosis: Experimental and clinical aspects

    SciTech Connect

    Scheinberg, L.; Raine, C.S.

    1984-01-01

    This book discusses the experimental and clinical aspects of multiple sclerosis. Specifically discussed are - Association of Epstein Barr Virus with pathology of central nervous system; immunology of viruses; and immunosuppression.

  19. Experimental evidence of the compressibility of arteries.

    PubMed

    Yosibash, Zohar; Manor, Itay; Gilad, Ilan; Willentz, Udi

    2014-11-01

    A definitive answer to the question whether artery walls are incompressible is to our opinion not yet categorically provided. Experimental-based evidence on the level of compressibility in artery walls is not easily achieved because of the difficulties associated with the measurement of very small differences in volumes under physiological pressure in these biological tissues. Past experiments aimed at addressing the question considered different species, different arteries, the experimental devices were not accurate enough and a statistical analysis of the results was missing. A precise experimental device together with a thorough testing protocol, a careful selection of arteries and a statistical analysis is presented for a definitive evaluation of the artery wall compressibility. We provide experimental evidence that in saphenous and femoral porcine arteries under physiological pressure range a relative compressibility of 2-6% is observed. The pre-assumption of incompressibility in many phenomenological constitutive models of artery walls should probably be re-evaluated.

  20. Demonstration before Experimentation: A Laboratory Philosophy.

    ERIC Educational Resources Information Center

    Chan, Ding-Yu; Bedworth, David D.

    1990-01-01

    Discusses the need for laboratory demonstrations prior to experimentation. Describes an introductory computer-assisted manufacturing (CAM) course and includes suggestions for teachers. Provides a model exercise on train control. (YP)

  1. Teaching the Inquiry Process through Experimental Mathematics

    ERIC Educational Resources Information Center

    Pudwell, Lara

    2017-01-01

    In this paper, we discuss the Experimental Mathematics course taught at Valparaiso University since 2009. We focus on aspects of the course that facilitate students' abilities to ask and explore their own research questions.

  2. 50 CFR 648.12 - Experimental fishing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (Atlantic surf clam and ocean quahog), F (NE multispecies and monkfish), G (summer flounder), H (scup), I...) Experimental fishing for surf clams or ocean quahogs will not require an allocation permit. (d)...

  3. Joint Actinide Shock Physics Experimental Research - JASPER

    ScienceCinema

    None

    2016-07-12

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  4. Joint Actinide Shock Physics Experimental Research - JASPER

    SciTech Connect

    2014-10-31

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  5. Yakima Hatchery Experimental Design : Annual Progress Report.

    SciTech Connect

    Busack, Craig; Knudsen, Curtis; Marshall, Anne

    1991-08-01

    This progress report details the results and status of Washington Department of Fisheries' (WDF) pre-facility monitoring, research, and evaluation efforts, through May 1991, designed to support the development of an Experimental Design Plan (EDP) for the Yakima/Klickitat Fisheries Project (YKFP), previously termed the Yakima/Klickitat Production Project (YKPP or Y/KPP). This pre- facility work has been guided by planning efforts of various research and quality control teams of the project that are annually captured as revisions to the experimental design and pre-facility work plans. The current objective are as follows: to develop genetic monitoring and evaluation approach for the Y/KPP; to evaluate stock identification monitoring tools, approaches, and opportunities available to meet specific objectives of the experimental plan; and to evaluate adult and juvenile enumeration and sampling/collection capabilities in the Y/KPP necessary to measure experimental response variables.

  6. Experimental study and evaluation of radioprotective drugs

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Thomson, J. F.

    1968-01-01

    Experimental study evaluates radioprotective drugs administered before exposure either orally or intravenously. Specifically studied are the sources of radiation, choice of radiation dose, choice of animals, administration of drugs, the toxicity of protective agents and types of protective drug.

  7. International review of experimental pathology. Volume 27

    SciTech Connect

    Richter, G.W.; Epstein, M.A.

    1985-01-01

    This book reviews the experimental pathology advancements made in recent years. Specifically discussed are - Epstein-Barr virus pathogenesis, immune deficient diseases, Hodgkin's disease, lymphomas and other lymphoproliferative disorders.

  8. Experimental Garden Plots for Botany Lessons

    ERIC Educational Resources Information Center

    Gorodnicheva, V. V.; Vasil'eva, E. I.

    1976-01-01

    Discussion of the botany lessons used at two schools points out the need for fifth and sixth grade students to be taught the principles of plant life through observations made at an experimental garden plot at the school. (ND)

  9. Depressed mood and smoking experimentation among preteens.

    PubMed

    Polen, Michael R; Curry, Susan J; Grothaus, Louis C; Bush, Terry M; Hollis, Jack F; Ludman, Evette J; McAfee, Timothy A

    2004-06-01

    The authors examined children's depressed mood, parental depressed mood, and parental smoking in relation to children's smoking susceptibility and experimentation over 20 months in a cohort of 418 preteens (ages 10-12 at baseline) and their parents. Depressed mood in preteens was strongly related to experimentation but not to susceptibility. In cross-sectional analyses parental depressed mood was related to children's experimentation, but in longitudinal analyses parental depressed mood at baseline did not differentiate children who experimented from those who did not. Although parental smoking was strongly related to experimentation, it was not related to susceptibility either cross-sectionally or longitudinally. Depressed mood among preteens and parents appeared to be more strongly related to children's smoking behaviors than to their intentions to smoke.

  10. Experimental design methods for bioengineering applications.

    PubMed

    Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

    2016-01-01

    Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

  11. An experimental study on microwave electron gun

    SciTech Connect

    Wang, G.; Wu, J.; Wang, Y.

    1995-12-31

    We report both the simulation and experimental results of using a ring cathode instead of the solid cathode to reduce the back bombardment effect of a thermionic cathode microwave electron gun. The result shows that the back bombardment power is decreased about 2/3 without changing the beam quality apparently which allows operation at higher repetition rate. Experimental results are compared with the simulation with good agreement.

  12. New experimental techniques for solar cells

    NASA Technical Reports Server (NTRS)

    Lenk, R.

    1993-01-01

    Solar cell capacitance has special importance for an array controlled by shunting. Experimental measurements of solar cell capacitance in the past have shown disagreements of orders of magnitude. Correct measurement technique depends on maintaining the excitation voltage less than the thermal voltage. Two different experimental methods are shown to match theory well, and two effective capacitances are defined for quantifying the effect of the solar cell capacitance on the shunting system.

  13. Joint Experimentation on Scalable Parallel Processors (JESPP)

    DTIC Science & Technology

    2006-04-01

    SCALABLE PARALLEL PROCESSORS (JESPP) 6. AUTHOR(S) Dan M. Davis, Robert F. Lucas, Ke-Thia Yao, Gene Wagenbreth 5. FUNDING NUMBERS C...List of Papers • Robert J. Graebener, Gregory Rafuse, Robert Miller & Ke-Thia Yao, “The Road to Successful Joint Experimentation Starts at the...2003. • Robert F. Lucas & Dan M. Davis, “Joint Experimentation on Scalable Parallel Processors“, Interservice/Industry Training, Simulation, and

  14. [Animal experimentation, computer simulation and surgical research].

    PubMed

    Carpentier, Alain

    2009-11-01

    We live in a digital world In medicine, computers are providing new tools for data collection, imaging, and treatment. During research and development of complex technologies and devices such as artificial hearts, computer simulation can provide more reliable information than experimentation on large animals. In these specific settings, animal experimentation should serve more to validate computer models of complex devices than to demonstrate their reliability.

  15. Experimental Evaluation of StRATUS (Preprint)

    DTIC Science & Technology

    2014-04-01

    AFRL-RQ-WP-TP-2014-0142 EXPERIMENTAL EVALUATION OF StRATUS (PREPRINT) Michael A. Falugi Structures Technology Branch Aerospace...Conference Paper Preprint 01 May 2012 – 28 February 2014 4. TITLE AND SUBTITLE EXPERIMENTAL EVALUATION OF StRATUS (PREPRINT) 5a. CONTRACT NUMBER...Steel Reinforced Advanced Thin Unitized Structure ( StRATUS ) is a new hybrid laminate concept composed of carbon fiber composite sandwiched between thin

  16. Experimental models of anxiety. Problems and perspectives.

    PubMed

    Griez, E

    1984-01-01

    In a brief review of the field of experimental psychopathology, the author observes that few adequate laboratory models of anxiety have been produced. Criteria to set up valid anxiety models are discussed. The carbon dioxide inhalation technique, an anxiomimetic intervention, is then proposed as a new human panic attack model and compared to the existing lactate infusion method. Both appear as promising agents in the experimental study of panic anxiety.

  17. An Experimental Analysis of Another Privacy

    ERIC Educational Resources Information Center

    Okouchi, Hiroto

    2006-01-01

    The present article discusses how events outside a subject's skin and not accessible to another subject but to an experimenter may contribute to experimental analyses of private events. Of 16 undergraduates, 8, referred to as instructors, first learned conditional discriminations (i.e., B1C1, B2C2, B3C3, and B4C4) in a standard matching-to-sample…

  18. [An experimental model of suppurative osteomyelitis].

    PubMed

    Privalov, V A; Svetlakov, A L; Kushakovskiĭ, O S; Ebert, L Ia; Giniatullin, R U; Svetlakova, I A; Iarovoĭ, N N

    2000-01-01

    A new experimental rabbit model of acute purulent osteomyelitis is proposed. The model is reproduced by percutaneous introduction of 4 million St. aureus microorganisms into the medullary channel of the femoral bone after aseptic destruction of the bone marrow by ethyl alcohol and hot saline. The model satisfies the demands of good reproduction, reduces probability of contamination of periosteal tissues during intraosteal inoculation and provides reproduction of local inflammation without its generalization which results in reduced number of fatal outcomes among experimental animals.

  19. In vivo experimental models of epilepsy.

    PubMed

    Rubio, Carmen; Rubio-Osornio, Moises; Retana-Márquez, Socorro; Verónica Custodio, Marisol López; Paz, Carlos

    2010-12-01

    This study reviews the different in vivo experimental models that have been used for the study of epileptogenesis. In this review we will focus on how to replicate the different models that have led to the study of partial seizures, as well as generalized seizures and the status epilepticus. The main characteristics that participate in the processes that generate and modulate the manifestations of different models of epileptogenesis are described. The development of several models of experimental epilepsy in animals has clearly helped the study of specific brain areas capable of causing convulsions. The experimental models of epilepsy also have helped in the study the mechanisms and actions of epilepsy drugs. In order to develop experimental animal models of epilepsy, animals are generally chosen according to the kind of epilepsy that can be developed and studied. It is currently known that animal species can have epileptic seizures similar to those in humans. However, it is important to keep in mind that it has not been possible to entirely evaluate all manifestations of human epilepsy. Notwithstanding, these experimental models of epilepsy have allowed a partial understanding of most of the underlying mechanisms of this disease.

  20. Evaluation of an experimental dental porcelain.

    PubMed

    Hamouda, Ibrahim M; El-Waseffy, Noha A; Hasan, Ahmed M; El-Falal, Abeer A

    2010-11-01

    The aim of this study was to evaluate fracture toughness, hardness, ceramic/metal bond strength and microstructure of experimental dental porcelain and compare it with commercial type. Specimens of specific dimensions were prepared. Fracture toughness was assessed by a three-point bending test. The Vickers hardness was measured using a microhardness tester. The ceramometal bond strength was measured using a universal testing machine. The load was applied at the porcelain/metal interface via a chisel edged blade with a crosshead speed of 2.0 mm/min until fracture. The polished specimens of dental porcelain were chemically etched and the microstructure was analyzed with a scanning electron microscope. The results showed comparable fracture toughness and bond strength for both materials, while the experimental porcelain exhibited higher hardness. The experimental porcelain showed uniform cohesive failure while the commercial type showed mixed mode of failure. The microstructure of the experimental porcelain was tetragonal leucite crystals dispersed randomly in a glass matrix. The leucite crystals exist in two forms, acicular and rod like structures. It was concluded that the experimental porcelain has adequate fracture toughness and ceramic/metal bond strength that can resist the rapid crack propagation and its consequent catastrophic failure, which indicates a material serviceability in the oral cavity.

  1. [Experimentation with women: science fiction or reality?].

    PubMed

    Villar Amigó, Vicente M

    2008-01-01

    Many people will not have heard about the experimentation that has been, and continues to be, carried out on women, because much of the media makes no mention of the matter. Just a few examples that could be mentioned are experimentation with the contraceptive pill, forced sterilization, egg donation, surrogate motherhood, kidney and other organ donation, and unnecessary therapy and surgery. In a few cases such experimentation could well be termed exploitation of women, with all kinds of excuses or humanitarian reasons, and sometimes communitarian purposes and even reasons concerning possible benefits for the whole of society, being mentioned. The present work aims to stimulate reflection about some types of research which can only be regarded as exploitation of women.

  2. Optimal Experimental Design for Model Discrimination

    PubMed Central

    Myung, Jay I.; Pitt, Mark A.

    2009-01-01

    Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it possible to determine these values, and thereby identify an optimal experimental design. After describing the method, it is demonstrated in two content areas in cognitive psychology in which models are highly competitive: retention (i.e., forgetting) and categorization. The optimal design is compared with the quality of designs used in the literature. The findings demonstrate that design optimization has the potential to increase the informativeness of the experimental method. PMID:19618983

  3. Women in the experimental analysis of behavior

    PubMed Central

    McSweeney, Frances K.; Swindell, Samantha

    1998-01-01

    We examined the status of women in the experimental analysis of behavior by comparing authorship by women in the Journal of the Experimental Analysis of Behavior (JEAB) to authorship by women in three similar journals. For all journals, the percentage of articles with at least one female author, the percentage of authors who are female, and the percentage of articles with a female first author increased from 1978 to 1997. However, the participation by women in JEAB lagged behind participation in the other journals on each measure. Female membership on the editorial board of JEAB also failed to increase from 1978 to 1997. Suggestions are made that may increase the participation of women in the experimental analysis of behavior. ImagesFigure 5 PMID:22478307

  4. Modern Experimental Techniques in Turbine Engine Testing

    NASA Technical Reports Server (NTRS)

    Lepicovsky, J.; Bruckner, R. J.; Bencic, T. J.; Braunscheidel, E. P.

    1996-01-01

    The paper describes application of two modern experimental techniques, thin-film thermocouples and pressure sensitive paint, to measurement in turbine engine components. A growing trend of using computational codes in turbomachinery design and development requires experimental techniques to refocus from overall performance testing to acquisition of detailed data on flow and heat transfer physics to validate these codes for design applications. The discussed experimental techniques satisfy this shift in focus. Both techniques are nonintrusive in practical terms. The thin-film thermocouple technique improves accuracy of surface temperature and heat transfer measurements. The pressure sensitive paint technique supplies areal surface pressure data rather than discrete point values only. The paper summarizes our experience with these techniques and suggests improvements to ease the application of these techniques for future turbomachinery research and code verifications.

  5. Experimental quantum fingerprinting with weak coherent pulses

    PubMed Central

    Xu, Feihu; Arrazola, Juan Miguel; Wei, Kejin; Wang, Wenyuan; Palacios-Avila, Pablo; Feng, Chen; Sajeed, Shihan; Lütkenhaus, Norbert; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds the promise of creating disruptive technologies that will play an essential role in future communication networks. For example, the study of quantum communication complexity has shown that quantum communication allows exponential reductions in the information that must be transmitted to solve distributed computational tasks. Recently, protocols that realize this advantage using optical implementations have been proposed. Here we report a proof-of-concept experimental demonstration of a quantum fingerprinting system that is capable of transmitting less information than the best-known classical protocol. Our implementation is based on a modified version of a commercial quantum key distribution system using off-the-shelf optical components over telecom wavelengths, and is practical for messages as large as 100 Mbits, even in the presence of experimental imperfections. Our results provide a first step in the development of experimental quantum communication complexity. PMID:26515586

  6. An experimental look into subelectron charge flow.

    PubMed

    Yerushalmi, Roie; Baldridge, Kim K; Scherz, Avigdor

    2003-10-22

    The prediction and measurement of charge distribution among interacting chemical entities in complex environments is a major challenge for modern chemistry. It encompasses information concerning fundamental quantities such as the electronic chemical potential and hardness of molecular fragments as well as their interactions with the surroundings. Although a wealth of theoretical work has been accumulated from the days of Pauling to the present, a specific molecular model system that allows quantitative and direct measurement of these properties has not yet been reported. Because atomic charges are not quantum mechanical observables, they cannot be derived from first principles, but rather they rely on the availability of high-precision experimental data and the interpretation of related experimental observables. Here, we demonstrate, for the first time, that a fragmental charge flow between a chelated metal center and reversibly bound molecules can be accurately monitored experimentally.

  7. Effect of cholecystokinin on experimental neuronal aging

    PubMed Central

    Sun, Xiao-Jiang; Lu, Qin-Chi; Cai, Yan

    2005-01-01

    AIM: To observe the effect of cholecystokinin (CCK) on lipofusin value, neuronal dendrite and spine ultrastructure, and total cellular protein during the process of experimental neuronal aging. METHODS: Experimental neuronal aging study model was established by NBA2 cellular serum-free culture method. By using single intracellular lipofusin value from microspectrophotometry, morphology of neuronal dendrites and spines from the scanner electron microscopy, and total cellular protein as the indexes of experimental neuronal aging, we observed the effect of CCK8 on the process of experimental neuronal aging. RESULTS: Under the condition of serum-free culture, intracellular fluorescence value (%) increased with the extension of culture time (1 d 8.51±3.43; 5 d 10.12±3.03; 10 d 20.54±10.3; 15 d 36.88±10.49; bP<0.01). When CCK was added to serum-free culture medium, intracellular lipofusin value (%) decreased remarkably after consecutive CCK reaction for 10 and 15 d (control 36.88±10.49; 5 d 32.03±10.01; 10 d 14.37±5.55; 15 d 17.31±4.80; bP<0.01). As the time of serum-free culturing was prolonged, the number of neuronal dendrite and spine cells decreased. The later increased in number when CCK8 was added. CCK8 could improve the total cellular protein in the process of experimental neuronal aging. CONCLUSION: CCK8 may prolong the process of experimental neuronal aging by maintaining the structure and the number of neuronal dendrite and spine cells and changing the total cellular protein. PMID:15641144

  8. Computatonal and experimental study of laminar flames

    SciTech Connect

    Smooke, M.D.; Long, M.B.

    1993-12-01

    This research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in counterflow, cylindrical and coflowing axisymmetric configurations. The authors have pursued both computational and experimental aspects of the research in parallel. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the one and two-dimensional nonlinear boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. In particular, spontaneous Raman scattering and laser induced fluorescence were used to measure the temperature, major and minor species profiles.

  9. Conceptual design report, CEBAF basic experimental equipment

    SciTech Connect

    1990-04-13

    The Continuous Electron Beam Accelerator Facility (CEBAF) will be dedicated to basic research in Nuclear Physics using electrons and photons as projectiles. The accelerator configuration allows three nearly continuous beams to be delivered simultaneously in three experimental halls, which will be equipped with complementary sets of instruments: Hall A--two high resolution magnetic spectrometers; Hall B--a large acceptance magnetic spectrometer; Hall C--a high-momentum, moderate resolution, magnetic spectrometer and a variety of more dedicated instruments. This report contains a short description of the initial complement of experimental equipment to be installed in each of the three halls.

  10. [Claude Bernard, founder of experimental physiology].

    PubMed

    Ren, Y; Li, X; Xu, W

    2001-07-01

    Claude Bernard was a famous French physiologist and philosopher in the 19th century. His experimental researches almost involved all fields of physiology. It is generally recognized by physiologists that in the research of Bernard in the digestion of pancreas, glucogenesis in the liver, and the vasomotor mechanism and the mechanism of action of curari and carbon monoxide were all at the lead. His researches established the foundation for modern physiology, modern biochemistry and the works of Pavlov, and were the initiation of experimental physiology.

  11. Experimental study of uncentralized squeeze film dampers

    NASA Technical Reports Server (NTRS)

    Quinn, R. D.

    1983-01-01

    The vibration response of a rotor system supported by a squeeze film damper (SFD) was experimentally investigated in order to provide experimental data in support of the Rotor/Stator Interactive Finite Element theoretical development. Part of the investigation required the designing and building of a rotor/SFD system that could operate with or without end seals in order to accommodate different SFD lengths. SFD variables investigated included clearance, eccentricity mass, fluid pressure, and viscosity and temperature. The results show inlet pressure, viscosity and clearance have significant influence on the damper performance and accompanying rotor response.

  12. Experimental verification of low sonic boom configuration

    NASA Technical Reports Server (NTRS)

    Ferri, A.; Wang, H. H.; Sorensen, H.

    1972-01-01

    A configuration designed to produce near field signature has been tested at M = 2.71 and the results are analyzed, by taking in account three-dimensional and second order effects. The configuration has an equivalent total area distribution that corresponds to an airplane flying at 60,000 ft. having a weight of 460,000 lbs, and 300 ft. length. A maximum overpressure of 0.95 lb/square foot has been obtained experimentally. The experimental results agree well with the analysis. The investigation indicates that the three-dimensional effects are very important when the measurements in wind tunnels are taken at small distances from the airplane.

  13. Experimental and Modeling Studies of Massif Anorthosites

    NASA Technical Reports Server (NTRS)

    Longhi, John

    1999-01-01

    This termination report covers the latter part of a single research effort spanning several grant cycles. During this time there was a single title, "Experimental and Modeling Studies of Massif Anorthosites", but there were several contract numbers as the mode and location of NASA contract administration changed. Initially, the project was funded as an increment to the PI's other grant, "Early Differentiation of the Moon: Experimental and Modeling Studies", but subsequently it became an independent grant. Table 1 contains a brief summary of the dates and contract numbers.

  14. Integrated pollutant removal: modeling and experimentation

    SciTech Connect

    Ochs, Thomas L.; Oryshchyn, Danylo B.; Summers, Cathy A.

    2005-01-01

    Experimental and computational work at the Albany Research Center, USDOE is investigating an integrated pollutant removal (IPR) process which removes all pollutants from flue gas, including SOX, NOX, particulates, CO2, and Hg. In combination with flue gas recirculation, heat recovery, and oxy-fuel combustion, the process produces solid, gas, and liquid waste streams. The gas exhaust stream comprises O2 and N2. Liquid streams contain H2O, SOX, NOX, and CO2. Computer modeling and low to moderate pressure experimentation are defining system chemistry with respect to SOX and H2O as well as heat and mass transfer for the IPR process.

  15. [Contribution of animal experimentation to pharmacology].

    PubMed

    Sassard, Jean; Hamon, Michel; Galibert, Francis

    2009-11-01

    Animal experimentation is of considerable importance in pharmacology and cannot yet be avoided when studying complex, highly integrated physiological functions. The use of animals has been drastically reduced in the classical phases of pharmacological research, for example when comparing several compounds belonging to the same pharmacological class. However, animal experiments remain crucial for generating and validating new therapeutic concepts. Three examples of such research, conducted in strict ethical conditions, will be used to illustrate the different ways in which animal experimentation has contributed to human therapeutics.

  16. Experimental level densities of atomic nuclei

    SciTech Connect

    Guttormsen, M.; Aiche, M.; Bernstein, L. A.; Bleuel, D. L.; Byun, Y.; Ducasse, Q.; Giacoppo, F.; Gorgen, A.; Gunsing, F.; Hagen, T. W.; Jurado, B.; Larsen, A. C.; Lebois, L.; Leniau, B.; Nyhus, H. T.; Renstrom, T.; Rose, S. J.; Sahin, E.; Siem, S.; Tornyi, T. G.; Tveten, G. M.; Voinov, A.; Wiedeking, M.; Wilson, J.

    2015-12-23

    It is almost 80 years since Hans Bethe described the level density as a non-interacting gas of protons and neutrons. In all these years, experimental data were interpreted within this picture of a fermionic gas. However, the renewed interest of measuring level density using various techniques calls for a revision of this description. In particular, the wealth of nuclear level densities measured with the Oslo method favors the constant-temperature level density over the Fermi-gas picture. Furthermore, trom the basis of experimental data, we demonstrate that nuclei exhibit a constant-temperature level density behavior for all mass regions and at least up to the neutron threshold.

  17. Experimental Demonstration of Adaptive Quantum State Estimation

    NASA Astrophysics Data System (ADS)

    Okamoto, Ryo; Iefuji, Minako; Oyama, Satoshi; Yamagata, Koichi; Imai, Hiroshi; Fujiwara, Akio; Takeuchi, Shigeki

    2012-09-01

    The first experimental demonstration of an adaptive quantum state estimation (AQSE) is reported. The strong consistency and asymptotic efficiency of AQSE have been mathematically proven [A. Fujiwara, J. Phys. A 39, 12489 (2006)JPHAC50305-447010.1088/0305-4470/39/40/014]. In this Letter, the angle of linear polarization of single photons, the phase parameter between the right and the left circularly polarization, is estimated using AQSE, and the strong consistency and asymptotic efficiency are experimentally verified. AQSE will provide a general useful method in both quantum information processing and metrology.

  18. Delta Clipper-Experimental (DC-X)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Pictured here is a DC-XA Reusable Launch Vehicle (RLV) prototype concept with an RLV logo. The Delta Clipper-Experimental (DC-X) was originally developed by McDornell Douglas for the Department of Defense (DOD). The DC-XA is a single-stage-to-orbit, vertical takeoff/vertical landing, launch vehicle concept, whose development is geared to significantly reduce launch costs and will provide a test bed for NASA Reusable Launch Vehicle (RLV) technology as the Delta Clipper-Experimental Advanced (DC-XA).

  19. Tandem mirror thermal barrier experimental program plan

    SciTech Connect

    Coensgen, F.H.; Drake, R.P.; Simonen, T.C.

    1980-01-02

    This report describes an experimental plan for the development of the Tandem Mirror Thermal Barrier. Included is: (1) a description of thermal barrier related physics experiments; (2) thermal barrier related experiments in the existing TMX and Phaedrus experiments; (3) a thermal barrier TMX upgrade; and (4) initiation of investigations of axisymmetric magnetic geometry. Experimental studies of the first two items are presently underway. Results are expected from the TMX upgrade by the close of 1981 and from axisymmetric tandem mirror experiments at the end of 1983. Plans for Phaedrus upgrades are developing for the same period.

  20. Lepton Flavor Violation. — Experimental

    NASA Astrophysics Data System (ADS)

    Aoki, M.

    2005-06-01

    Lepton flavor violation (LFV) in the charged sector has been gaining great interests these days. Experimental researches looking for muon LFV such as MEG and MECO are in preparation, and aiming to discover the muon LFV signal within this decade. There is also another activity called PRISM/PRIME project underway, which aims to expand muon LFV research furthermore. The status of those experimental studies will be described. The idea of building Muon Factory and its relevance to the future of neutrino physics is also commented upon.

  1. Macrophages and Uveitis in Experimental Animal Models

    PubMed Central

    Mérida, Salvador; Palacios, Elena; Bosch-Morell, Francisco

    2015-01-01

    Resident and infiltrated macrophages play relevant roles in uveitis as effectors of innate immunity and inductors of acquired immunity. They are major effectors of tissue damage in uveitis and are also considered to be potent antigen-presenting cells. In the last few years, experimental animal models of uveitis have enabled us to enhance our understanding of the leading role of macrophages in eye inflammation processes, including macrophage polarization in experimental autoimmune uveoretinitis and the major role of Toll-like receptor 4 in endotoxin-induced uveitis. This improved knowledge should guide advantageous iterative research to establish mechanisms and possible therapeutic targets for human uveitis resolution. PMID:26078494

  2. Experimental aerothermodynamic research of hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Cleary, Joseph W.

    1990-01-01

    Wind tunnel tests were conducted to establish a benchmark experimental data base for a genetic hypersonic aircraft vehicle. Comprehensive measurements were made at Mach 7 to give flow visualization, surface pressure, surface convective heat transfer, and flow field Pitot pressure for a delta platform all-body vehicle. The tests were conducted in the NASA/Ames 3.5-Foot Hypersonic Wind Tunnel at Reynolds numbers sufficient to give turbulent flow. Comparisons are made of the experimental results with computational solutions of the flow by an upwind parabolized Navier-Stokes code developed at Ames. Good agreement of experiment with solutions by the code is demonstrated.

  3. Identification of Experimental Unsteady Aerodynamic Impulse Responses

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.; Piatak, David J.; Scott, Robert C.

    2003-01-01

    The identification of experimental unsteady aerodynamic impulse responses using the Oscillating Turntable (OTT) at NASA Langley's Transonic Dynamics Tunnel (TDT) is described. Results are presented for two configurations: a Rigid Semispan Model (RSM) and a rectangular wing with a supercritical airfoil section. Both models were used to acquire unsteady pressure data due to pitching oscillations on the OTT. A deconvolution scheme involving a step input in pitch and the resultant step response in pressure, for several pressure transducers, is used to identify the pressure impulse responses. The identified impulse responses are then used to predict the pressure response due to pitching oscillations at several frequencies. Comparisons with the experimental data are presented.

  4. An Experimental Study of Thrust Augmenting Ejectors

    DTIC Science & Technology

    1983-12-01

    A , AN EXPERIMENTAL STUDY OF THRUST AUG’XENTING EJECTORS THESIS William D. Lewis Captain 11. S. Army AFIT/GAE/Ai/83D- 13 1 DTIC Li~i ELECTE JANI...83D-13 AN LEPERIMENTAL STUDY OF THRUST AUG-M..TING EJECTORS "l•HSIS William D. Levis Captain U. S. Army AF1T/GAAE/AA/$3D- 13 ’jK Approved for public...release; distribution unliaited I V .,, AFIT/GAE/AA/83D- 13 AN EXPERIMENTAL STUDY OF THRUST AUGMENTING EJECTORS THESIS Presented to *he Faculty of the

  5. Experimental Methodology in English Teaching and Learning: Method Features, Validity Issues, and Embedded Experimental Design

    ERIC Educational Resources Information Center

    Lee, Jang Ho

    2012-01-01

    Experimental methods have played a significant role in the growth of English teaching and learning studies. The paper presented here outlines basic features of experimental design, including the manipulation of independent variables, the role and practicality of randomised controlled trials (RCTs) in educational research, and alternative methods…

  6. Children's Understanding of Experimental Contrast and Experimental Control: An Inventory for Primary School

    ERIC Educational Resources Information Center

    Osterhaus, Christopher; Koerber, Susanne; Sodian, Beate

    2015-01-01

    Experimentation skills are a central component of scientific thinking, and many studies have investigated whether and when primary-school children develop adequate experimentation strategies. However, the answers to these questions vary substantially depending on the type of task that is used: while discovery tasks, which require children to…

  7. Comparison of the experimental aerodynamic characteristics of theoretically and experimentally designed supercritical airfoils

    NASA Technical Reports Server (NTRS)

    Harris, C. D.

    1974-01-01

    A lifting airfoil theoretically designed for shockless supercritical flow utilizing a complex hodograph method has been evaluated in the Langley 8-foot transonic pressure tunnel at design and off-design conditions. The experimental results are presented and compared with those of an experimentally designed supercritical airfoil which were obtained in the same tunnel.

  8. Reconciling Experimental and Quasi-Experimental Evidence on the Impact of Full-Day Kindergarten

    ERIC Educational Resources Information Center

    Gibbs, Chloe

    2013-01-01

    This paper addresses the question of how to interpret evidence on the impact of full-day kindergarten resulting from different study designs, and provides guidance on how this evidence taken in tandem may inform the design and implementation of full-day kindergarten policies. Incorporating both experimental and quasi-experimental estimates on…

  9. Didactic Objects for Development of Young Children's Combinatorial Experimentation and Causal-Experimental Thought

    ERIC Educational Resources Information Center

    Poddiakov, Alexander

    2011-01-01

    Combinatorial abilities are fundamental to experimental thinking. The aim of this work was to design didactic objects that will stimulate preschoolers' experimental thinking and to study young children's thinking in relation to these objects. Six heuristic rules for the design of didactic objects are specified, and the responses of 623 children…

  10. Students' Epistemologies about Experimental Physics: Validating the Colorado Learning Attitudes about Science Survey for Experimental Physics

    ERIC Educational Resources Information Center

    Wilcox, Bethany R.; Lewandowski, H. J.

    2016-01-01

    Student learning in instructional physics labs represents a growing area of research that includes investigations of students' beliefs and expectations about the nature of experimental physics. To directly probe students' epistemologies about experimental physics and support broader lab transformation efforts at the University of Colorado Boulder…

  11. Yeast: An Experimental Organism for Modern Biology.

    ERIC Educational Resources Information Center

    Botstein, David; Fink, Gerald R.

    1988-01-01

    Discusses the applicability and advantages of using yeasts as popular and ideal model systems for studying and understanding eukaryotic biology at the cellular and molecular levels. Cites experimental tractability and the cooperative tradition of the research community of yeast biologists as reasons for this success. (RT)

  12. Experimentally Evoking Nonbelieved Memories for Childhood Events

    ERIC Educational Resources Information Center

    Otgaar, Henry; Scoboria, Alan; Smeets, Tom

    2013-01-01

    We report on the 1st experimental elicitation of nonbelieved memories for childhood events in adults (Study 1) and children (Study 2) using a modified false memory implantation paradigm. Participants received true (trip to a theme park) and false (hot air balloon ride) narratives and recalled these events during 2 interviews. After debriefing, 13%…

  13. Symposium on Recent Developments in Experimental Psychopathology.

    ERIC Educational Resources Information Center

    Dawson, Geraldine

    An overview of some of the recent developments in experimental research on early infantile autism considers related issues such as language impairments, cognitive and affective deficits, nonverbal communication, social behavior, and therapeutic interventions. Research indicates that difficulty with abstract use of language and with pragmatic…

  14. Meditation: Rationales, Experimental Effects, and Methodological Issues

    DTIC Science & Technology

    1986-04-01

    p.308). Movements as diverse as Buddhist and transcendental meditation. Theosophy. and Juncian and Transpersonal psychologies have emphasized... Transpersonal and Humanistic psychologists have been especially active in merging concepts from Eastern systems of meditation with current Western...experimental and therapeutic procedures. The establishment of professional associations devoted to Transpersonal and Humanistic psychology, and the

  15. Comparing fluid mechanics models with experimental data.

    PubMed

    Spedding, G R

    2003-09-29

    The art of modelling the physical world lies in the appropriate simplification and abstraction of the complete problem. In fluid mechanics, the Navier-Stokes equations provide a model that is valid under most circumstances germane to animal locomotion, but the complexity of solutions provides strong incentive for the development of further, more simplified practical models. When the flow organizes itself so that all shearing motions are collected into localized patches, then various mathematical vortex models have been very successful in predicting and furthering the physical understanding of many flows, particularly in aerodynamics. Experimental models have the significant added convenience that the fluid mechanics can be generated by a real fluid, not a model, provided the appropriate dimensionless groups have similar values. Then, analogous problems can be encountered in making intelligible but independent descriptions of the experimental results. Finally, model predictions and experimental results may be compared if, and only if, numerical estimates of the likely variations in the tested quantities are provided. Examples from recent experimental measurements of wakes behind a fixed wing and behind a bird in free flight are used to illustrate these principles.

  16. 1972 Inspection of Experimental Marine Piling.

    DTIC Science & Technology

    The 54 Cooperative piles at Coco Solo, Canal Zone, and the 267 Cooperative and NCEL experimental piles at Pearl Harbor, Hawaii were inspected during...the periods February 22 to 25 and March 17 to 24, 1972, respectively. After 9 years of exposure at Coco Solo, 11 of the 12 piles treated with 70/30

  17. 1970 Inspection of Experimental Marine Piling.

    DTIC Science & Technology

    The 54 Cooperative piles at Coco Solo, Canal Zone and the 273 Cooperative and NCEL experimental piles at Pearl Harbor, Hawaii were inspected during...the weeks of 9 and 23 March 1970, respectively. After 7 years of exposure at Coco Solo, 9 of the 12 piles treated with creosote-coal tar showed borer

  18. Drosophila Melanogaster as an Experimental Organism.

    ERIC Educational Resources Information Center

    Rubin, Gerald M.

    1988-01-01

    Discusses the role of the fruit fly in genetics research requiring a multidisciplinary approach. Describes embryological and genetic methods used in the experimental analysis of this organism. Outlines the use of Drosophila in the study of the development and function of the nervous system. (RT)

  19. Inspection procedures for experimental fuel production

    NASA Astrophysics Data System (ADS)

    Campsie, I. C.; Rattray, H. D.

    1988-04-01

    This paper describes the inspection procedures used in the development and manufacture of experimental fuel elements and their components. The examples quoted mainly apply to the PFR experimental fuel programme, although for well over a quarter of a century the procedures and techniques have been progressively developed and applied to the Magnox, SGHW, AGR, HTR, PFR and PWR fuel development programmes undertaken at the UKAEA's Springfields and Windscale Nuclear Power Development Laboratories. In contrast to production runs involving large numbers of standard components, experimental fuel is often assembled from components which, while they may look alike, may have design and material variations. Thus in addition to normal batching and bonding operations, great emphasis has to be placed on dimensional inspection, material testing and the individual identification of all items, thus maintaining traceability throughout all operations. The quality and performance of experimental items are often evaluated comparing pre- and post-test dimensional or NDT measurements. In the case of irradiation tests, several years can elapse between the measurements, therefore it is essential to ensure the reproducibility and compatibility of pre- and post-test measuring techniques and the traceability of all measured data and standards.

  20. Experimental validation of structural optimization methods

    NASA Technical Reports Server (NTRS)

    Adelman, Howard M.

    1992-01-01

    The topic of validating structural optimization methods by use of experimental results is addressed. The need for validating the methods as a way of effecting a greater and an accelerated acceptance of formal optimization methods by practicing engineering designers is described. The range of validation strategies is defined which includes comparison of optimization results with more traditional design approaches, establishing the accuracy of analyses used, and finally experimental validation of the optimization results. Examples of the use of experimental results to validate optimization techniques are described. The examples include experimental validation of the following: optimum design of a trussed beam; combined control-structure design of a cable-supported beam simulating an actively controlled space structure; minimum weight design of a beam with frequency constraints; minimization of the vibration response of helicopter rotor blade; minimum weight design of a turbine blade disk; aeroelastic optimization of an aircraft vertical fin; airfoil shape optimization for drag minimization; optimization of the shape of a hole in a plate for stress minimization; optimization to minimize beam dynamic response; and structural optimization of a low vibration helicopter rotor.

  1. Experimental Study of the Current Filamentation Instability

    NASA Astrophysics Data System (ADS)

    Allen, Brian; Muggli, Patric; Silva, Luis O.; Martins, Joana; Yakimenko, Vitaly; Fedurin, Mikhail; Kusche, Karl; Babzien, Marcus; Huang, Chengkun; Mori, Warren

    2012-10-01

    The Current Filamentation Instability (CFI) is of central importance for the propagation of relativistic electron beams in plasmas. CFI has potential relevance to astrophysics, afterglow of gamma ray bursts, inertial confinement fusion, energy transport in the fast-igniter concept, and places an upper limit on the plasma density and accelerating gradient in PWFA's. An experimental study at the Accelerator Test Facility at Brookhaven National Laboratory with the 60MeV e^- beam and cm length plasma. The experiment included the systematic study and characterization of the instability as a function of the beam charge and plasma density. The transverse beam profile is measured directly at the plasma exit using OTR. Experimental results show the transition from plasma focusing to CFI near kpσr=1 characterized by the appearance of multiple (1-5) beam filaments and scaling of the transverse filament size with the plasma skin depth. Suppression of the instability is seen by lowering the growth rate of the instability by reducing the beam charge. The experimental results are in excellent agreement with theory and simulations and we present and discuss simulation and experimental results.

  2. Physical Science Laboratory Manual, Experimental Version.

    ERIC Educational Resources Information Center

    Cooperative General Science Project, Atlanta, GA.

    Provided are physical science laboratory experiments which have been developed and used as a part of an experimental one year undergraduate course in general science for non-science majors. The experiments cover a limited number of topics representative of the scientific enterprise. Some of the topics are pressure and buoyancy, heat, motion,…

  3. Upper Washita River experimental watersheds: Sediment Database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving the scientific understanding of the effectiveness of watershed conservation practices and floodwater-retardation structures to control floods and soil erosion is one of the primary objectives for sediment studies in the upper Washita River Experimental Watersheds. This paper summarizes se...

  4. Evaluation and experimentation with duck management strategies

    USGS Publications Warehouse

    Nichols, J.D.; Johnson, F.A.

    1989-01-01

    Our knowledge of the effects of hunting regulations on duck populations has been based largely on retrospective studies of historical data. We have reached the limits of what can be learned in this way. Future knowledge gains will likely come about only through experimentation and adaptive management.

  5. An experimental X band phased array

    NASA Astrophysics Data System (ADS)

    Rao, N. P. R.; Limaye, K. U.; Ramalingam, R. P.; Gangadharan, T. S.; Bhandopadhyay, G.; Deshpande, P. A.

    1983-10-01

    The details of an X band experimental 11 x 11 element Phased Array Antenna of phased lens configuration with a monopulse space feed developed at LRDE are presented. The studies carried and the results obtained on collimation, beam steering, pattern variation with scan, array operation in two-dimensional search, dedicated track and track while scan (TWS) are also given.

  6. Comparing fluid mechanics models with experimental data.

    PubMed Central

    Spedding, G R

    2003-01-01

    The art of modelling the physical world lies in the appropriate simplification and abstraction of the complete problem. In fluid mechanics, the Navier-Stokes equations provide a model that is valid under most circumstances germane to animal locomotion, but the complexity of solutions provides strong incentive for the development of further, more simplified practical models. When the flow organizes itself so that all shearing motions are collected into localized patches, then various mathematical vortex models have been very successful in predicting and furthering the physical understanding of many flows, particularly in aerodynamics. Experimental models have the significant added convenience that the fluid mechanics can be generated by a real fluid, not a model, provided the appropriate dimensionless groups have similar values. Then, analogous problems can be encountered in making intelligible but independent descriptions of the experimental results. Finally, model predictions and experimental results may be compared if, and only if, numerical estimates of the likely variations in the tested quantities are provided. Examples from recent experimental measurements of wakes behind a fixed wing and behind a bird in free flight are used to illustrate these principles. PMID:14561348

  7. Experimental Stream Facility: Design and Research

    EPA Science Inventory

    The Experimental Stream Facility (ESF) is a valuable research tool for the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development’s (ORD) laboratories in Cincinnati, Ohio. This brochure describes the ESF, which is one of only a handful of research facilit...

  8. Animal Experimentation: Issues for the 1980s.

    ERIC Educational Resources Information Center

    Zola, Judith C.; And Others

    1984-01-01

    Examines the extent to which issues related to animal experimentation are in conflict and proposes choices that might least comprise them. These issues include animal well-being, human well-being, self-interest of science, scientific validity and responsibility, progress in biomedical and behavioral science, and the future quality of medical care.…

  9. Experimental Evolution of Antibiotic Resistance in Bacteria

    ERIC Educational Resources Information Center

    Krist, Amy C.; Showsh, Sasha A.

    2007-01-01

    Evolution is typically measured as a change in allele or genotype frequencies over one or more generations. Consequently, evolution is difficult to show experimentally in a semester-long lab course because most organisms have longer generation times than 15 weeks. In this article, the authors present an experiment to demonstrate and study…

  10. Strategies of Communication in Recent Experimental Theatre.

    ERIC Educational Resources Information Center

    Phillips, Jerrold A.

    Because it focuses on questions of communication, the experimental theatre of the 1970s, particularly that created by Robert Wilson and Richard Foreman, can be analyzed according to two distinct theories regarding the communication process. The first theory defines communication as a process in which the communicator selects and transmits messages…

  11. Essays on Experimental Economics and Education

    ERIC Educational Resources Information Center

    Ogawa, Scott Richard

    2013-01-01

    In Chapter 1 I consider three separate explanations for how price affects the usage rate of a purchased product: Screening, signaling, and sunk-cost bias. I propose an experimental design that disentangles the three effects. Furthermore, in order to quantify and compare these effects I introduce a simple structural model and show that the…

  12. Experimental Results in DIS from Jefferson Laboratory

    SciTech Connect

    Sebastian Kuhn

    2009-10-01

    We are summarizing the experimental program of Jefferson Lab (Thomas Jefferson National Accelerator Facility in Newport News, VA) in deep inelastic electron scattering. We show recent results and discuss future plans for both the present 6 GeV era and the 12 GeV energy-upgraded facility.

  13. 50 CFR 648.12 - Experimental fishing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... mackerel, squid, and butterfish), D (Atlantic sea scallop), E (Atlantic surf clam and ocean quahog), F (NE... vessel seeking the benefit of such exemption. (c) Experimental fishing for surf clams or ocean quahogs... § 648.12, the introductory text was amended by removing the words “surf clam” and adding the...

  14. Investigations on Experimental Impellers for Axial Blowers

    NASA Technical Reports Server (NTRS)

    Encke, W.

    1947-01-01

    A selection of measurements obtained on experimental impellers for axial blowers will be reported. In addition to characteristic curves plotted for low and for high peripheral velocities, proportions and blade sections for six different blower models and remarks on the design of blowers will be presented.

  15. Simulation as an Aid to Experimental Design.

    ERIC Educational Resources Information Center

    Frazer, Jack W.; And Others

    1983-01-01

    Discusses simulation program to aid in the design of enzyme kinetic experimentation (includes sample runs). Concentration versus time profiles of any subset or all nine states of reactions can be displayed with/without simulated instrumental noise, allowing the user to estimate the practicality of any proposed experiment given known instrument…

  16. 50 CFR 665.17 - Experimental fishing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Experimental fishing. 665.17 Section 665.17 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... fishery management agency of the affected state, accompanied by the following information: (i) The...

  17. Collective Experimentation: Lessons from the Field

    ERIC Educational Resources Information Center

    Misiko, M.

    2009-01-01

    The purpose of this paper is to document smallholder experiences during a participatory experimental initiative and draw useful lessons for field practitioners. The main methods used to collect data were participant observation, in-depth interviews among 40 farmers, and analyses of notes taken during participatory monitoring and evaluation. These…

  18. Optimal Experimental Design for Model Discrimination

    ERIC Educational Resources Information Center

    Myung, Jay I.; Pitt, Mark A.

    2009-01-01

    Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it…

  19. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  20. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  1. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  2. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  3. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT.... Participating in air races, including (for such participants) practicing for such air races and flying to...

  4. An Experimental Investigation of Cognitive Defusion

    ERIC Educational Resources Information Center

    Pilecki, Brian C.; McKay, Dean

    2012-01-01

    The current study compared cognitive defusion with other strategies in reducing the impact of experimentally induced negative emotional states. Sixty-seven undergraduates were assigned to one of three conditions (cognitive defusion, thought suppression, or control) and instructed in standardized approaches relevant to each condition before viewing…

  5. Experimental Demonstrations in Teaching Chemical Reactions.

    ERIC Educational Resources Information Center

    Hugerat, Muhamad; Basheer, Sobhi

    2001-01-01

    Presents demonstrations of chemical reactions by employing different features of various compounds that can be altered after a chemical change occurs. Experimental activities include para- and dia-magnetism in chemical reactions, aluminum reaction with base, reaction of acid with carbonates, use of electrochemical cells for demonstrating chemical…

  6. Experimental prototype instruments for nondestructive testing

    SciTech Connect

    Smolyakova, L.E.

    1987-10-01

    Results are given of state acceptance tests on experimental prototype nondestructive testing instruments along with their technical specifications and advantages over the better Soviet and foreign counterparts. The instruments include the UF-10P ultrasonic hydrostatic testing instrument, the PRIZ-12 piezoelectric transducer, and the RTVK-2K and LEB-1K radioisotope thickness gages.

  7. Experimental velocity distributions in a granular submonolayer

    NASA Astrophysics Data System (ADS)

    Cadillo-Martínez, Alejandra T.; Sánchez, Rodrigo

    2017-01-01

    Experimental speed distributions are obtained for driven granular submonolayers of binary mixtures of single spheres and dimers of spheres. The results are well-described by a distribution originally developed for a single-species one-dimensional system. This suggests that such a distribution may be extended to other mixtures such as systems exhibiting aggregation and dissociation.

  8. 14 CFR 21.475 - Experimental certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.475 Section 21.475 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Designated Alteration Station Authorization Procedures §...

  9. How experimental trial context affects perceptual categorization.

    PubMed

    Palmeri, Thomas J; Mack, Michael L

    2015-01-01

    To understand object categorization, participants are tested in experiments often quite different from how people experience object categories in the real world. Learning and knowledge of categories is measured in discrete experimental trials, those trials may or may not provide feedback, trials appear one after another, after some fixed inter-trial interval, with hundreds of trials in a row, within experimental blocks with some structure dictated by the experimental design. In the real world, outside of certain educational and vocational contexts, opportunities to learn and use categories are intermixed over time with a whole multitude of intervening experiences. It is clear from any elementary understanding of human cognition that sequential effects matter, yet this understanding is often ignored, and categorization trials are often instead treated as independent events, immune to local trial context. In this perspective, we use some of our work to illustrate some of the consequences of the fact that categorization experiments have a particular trial structure. Experimental trial context can affect performance in category learning and categorization experiments in ways that can profoundly affect theoretical conclusions.

  10. Experimental and computational study of thaumasite structure

    SciTech Connect

    Scholtzová, Eva; Kucková, Lenka; Kožíšek, Jozef; Pálková, Helena; Tunega, Daniel

    2014-05-01

    The structure of thaumasite has been studied experimentally by means of a single crystal X-ray diffraction and FTIR methods, and theoretically using density functional theory (DFT) method. Very good agreement was achieved between calculated and experimental structural parameters. In addition, calculations offered the refinement of the positions of the hydrogen atoms. The detailed analysis of the hydrogen bonds existing in the thaumasite structure has been performed. Several types of hydrogen bonds have been classified. The water molecules coordinating Ca{sup 2+} cation act as proton donors in moderate O-H···O hydrogen bonds formed with CO₃⁻²and SO₄⁻² anions. The multiple O-H···O hydrogen bonds exist among water molecules themselves. Finally, relatively weak hydrogen bonds form water molecules with the OH groups from the coordination sphere of the Si(OH)₆⁻² anion. Further, calculated vibrational spectrum allowed complete assignment of all vibrational modes which are not available from the experimental spectrum that has a complex structure with overlapped bands, especially below 1500 cm⁻¹. Highlights: • The thaumasite structure was studied experimentally and using DFT method. • We used DFT method for the refinement of the positions of hydrogen atoms. • A detailed analysis of the hydrogen bonds was done. • A complete assignment of all bands to particular types of vibrations was done.

  11. GUIDE-0: An Experimental Information System.

    ERIC Educational Resources Information Center

    Murai, Shinnichi

    A description is provided of GUIDE-0, an experimental information system. The system serves as a bibliographic aid for students who are taking introductory computer science courses whose material is at least partially implemented via PLATO-IV lessons. Following a brief introduction to the system in Chapter I, the second Chapter describes the…

  12. Using Experimental Methods in Higher Education Research

    ERIC Educational Resources Information Center

    Ross, Steven M.; Morrison, Gary R.; Lowther, Deborah L.

    2005-01-01

    Experimental methods have been used extensively for many years to conduct research in education and psychology. However, applications of experiments to investigate technology and other instructional innovations in higher education settings have been relatively limited. The present paper examines ways in which experiments can be used productively…

  13. Growing Plants Without Soil for Experimental Use.

    ERIC Educational Resources Information Center

    Blankendaal, M.; And Others

    Much of the current research in experimental plant biology requires highly uniform plants. To achieve this, many plants are grown under conditions in which the environment is carefully manipulated. This pamphlet has been prepared, therefore, to present and describe growth procedures which will produce vigorous, healthy, uniform plant material in…

  14. MATHEMATICS I, VOLUME 3, EXPERIMENTAL EDITION.

    ERIC Educational Resources Information Center

    Secondary School Mathematics Curriculum Improvement Study, New York, NY.

    THIS IS VOLUME 3 OF A THREE-VOLUME EXPERIMENTAL EDITION CONTAINING A SEQUENCE OF ENRICHED MATERIALS FOR SEVENTH-GRADE MATHEMATICS. THESE MATERIALS ARE DESIGNED TO BE USED FOR A PROGRAM OF INDIVIDUALIZED INSTRUCTION FOR THE ACCELERATED STUDENT OR FOR CLASSROOM PRESENTATION BY THE TEACHER. THE PRESENTATION OF THE MATERIAL IS SUCH AS TO REFLECT…

  15. PROJECT CONCERN, HARTFORD'S EXPERIMENTAL BUSING PROGRAM.

    ERIC Educational Resources Information Center

    SHAW, PEG

    THIS REPRINTED SERIES OF NEWSPAPER ARTICLES ABOUT PROJECT CONCERN, HARTFORD'S EXPERIMENTAL PROGRAM WHICH BUSES INNER CITY CHILDREN TO SUBURBAN SCHOOLS, IS COMPOSED PRIMARILY OF ANECDOTAL REPORTS FROM MOTHERS, CHILDREN, AND TEACHERS. THE INDIVIDUAL ARTICLES DEAL WITH THE CHILDREN'S REACTIONS TO THE BUSING AND TO THEIR NEW SCHOOLS, THEIR ADJUSTMENT,…

  16. Experimental interstellar organic chemistry - Preliminary findings

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Sagan, C.

    1973-01-01

    Review of the results of some explicit experimental simulation of interstellar organic chemistry consisting in low-temperature high-vacuum UV irradiation of condensed simple gases known or suspected to be present in the interstellar medium. The results include the finding that acetonitrile may be present in the interstellar medium. The implication of this and other findings are discussed.

  17. Reflections on Experimental Research in Medical Education

    ERIC Educational Resources Information Center

    Cook, David A.; Beckman, Thomas J.

    2010-01-01

    As medical education research advances, it is important that education researchers employ rigorous methods for conducting and reporting their investigations. In this article we discuss several important yet oft neglected issues in designing experimental research in education. First, randomization controls for only a subset of possible confounders.…

  18. Comportement des piles de ponts sous l'effet multidirectionnel des mouvements sismiques

    NASA Astrophysics Data System (ADS)

    Khaled, Amar

    A comprehensive study has been conducted to investigate the seismic behaviour of bridge columns under bidirectional earthquake ground motions. The study comprises a series of linear elastic and non-linear dynamic analyses on a set of regular bridge structures representative of common type bridges that are encountered the most in North American highways, as well as bidirectional cyclic testing of four half-scale rectangular reinforced concrete bridge columns. The first part of the study was aimed at investigating the adequacy and effectiveness of the 30%- rule, at predicting the seismic demand on bridge columns when subjected to bi-directional earthquake motions. A series of multiple time-history analyses performed on nine generic bridge models to determine the exact seismic critical bi-axial response of the bridge columns under pairs of orthogonal seismic ground motion time-histories. Response spectrum analyses were also carried out, using the acceleration spectra of the orthogonal ground motion components, to determine the maximum bi-axial response in each direction and the critical bi-axial response was estimated using the 30%-Rule, as specified by the CSA S6 and the AASHTO bridge design code and regulations. In the second part of the study, a new Percentage Rule for the prediction of interacting seismic responses of bridge columns under multi-directional earthquake components is derived for the two sites. A total of 14 regular bridges with different geometrical properties were examined for the two sites. The new rule was developed by comparing the column longitudinal steel ratio required from response spectrum analysis with combination rules to the ratio determined from the results of multiple linear dynamic time history analysis of the bridge structures under bidirectional ground motions. The steel ratios were computed for the bending moment demand from response spectrum analysis using the combination rule with different values of the weighted percentage alpha (0, 0.3, and 1.0) and the skew angle (10° to 45°). These ratios were compared to those obtained from multiple elastic time history analyses to identify the bridge properties that influence the most the combination rule. In this last part of the study, the need for combination rules to account for seismic demand from the simultaneous action of bidirectional horizontal ground motion earthquake components and the current CSA S6 requirements regarding the lower limit of 0.8% on the longitudinal reinforcement ratio and the transverse reinforcement for confinement for bridge columns were examined through bidirectional cyclic tests on four identical half-scale reinforced concrete rectangular bridge column specimens. The prototype structures are regular common two-span, skewed bridge structures designed according to CSA S6-06, and the study focused on the demand from earthquakes expected in Eastern and Western Canada. The column specimens are 1.2 m x 0.6 m in cross-section and 3.0 m tall, with axial loads varying between 4.5 to 9.3% Agf'c. Two specimens were designed for Montreal, QC, Canada (east site) using 0% and 30% combination rules, resulting in longitudinal steel ratios of 0.41% and 0.57%. Two specimens represented columns part of bridges located in Vancouver, BC, Canada (west site), with longitudinal steel ratios of 0.97% and 1.72% resulting from the application of 0% and 40% combination rules. Site specific cyclic displacement test protocols were developed from time history analysis of the bridge structures that were previously performed in the second part of the study. All columns exhibited satisfactory inelastic cyclic bidirectional response up to high ductility levels. For both sites, the Combination Rules used in design had no significant influence on the inelastic cyclic response of the columns. The columns designed for the Montreal site exhibited satisfactory inelastic cyclic performance even if they had longitudinal reinforcement ratio less than the current CSA S6 limit of 0.8%. Buckling and rupture of corner bars were however observed at high ductility levels in two specimens, showing the need for additional restraint for these bars and more stringent requirements for transverse reinforcement in columns subjected to bi-axial loading. For all specimens, the height of the plastic hinge region was approximately equal to the smaller column dimension, rather than the larger one as currently specified in CSA S6. (Abstract shortened by UMI.)

  19. Comportement en fatigue et influence de la temperature sur les proprietes en traction du PLA

    NASA Astrophysics Data System (ADS)

    Menard, Claire

    Current environmental issues reduce the use of materials obtained from fossil resources. The usual plastics therefore tend to be replaced by more green polymers such as polylactic acid (PLA), a bio-based and biodegradable polymer. Knowledge on the properties of this material is essential, especially in terms of fatigue strength and influence of temperature on tensile stiffness and strength. In this study, the PLA samples are submitted to monotonic tensile tests, according to ASTM D638-10, at various temperatures between room temperature (23°C) and the glass transition temperature of the material (55-60°C). The results show a decrease of 30% of the modulus of elasticity and 60% of the tensile strength between these two temperatures. This decrease is mainly due to a significant drop in the mechanical properties beyond 50°C. In addition, tensile fatigue tests were conducted at loads rate between 40 and 80% of tensile strength, at room temperature in order to plot the Wohler curve of PLA. The ruptured specimens were finally observed with a scanning electron microscope (SEM) to analyze the failure mechanisms in fatigue of PLA.

  20. Dealing with Behavioral Problems: Rules of Comportment in the Science Lecture.

    ERIC Educational Resources Information Center

    Druger, Marvin

    2001-01-01

    Highlights some ways that instructors of large lecture classes can effectively deal with such issues as inappropriate talking; tardiness; leaving early; sleeping, eating, or drinking during class; listening to music; or simply being discourteous. (SAH)

  1. Civility, comportment, and the anatomy theater: Girolamo Fabrici and his medical students in Renaissance Padua.

    PubMed

    Klestinec, Cynthia

    2007-01-01

    Public anatomies have been characterized as carnivalesque events: like the Carnival, they took place in January and February and celebrated bodily existence. However, in late sixteenth-century Padua and its famous anatomy theater, the annual, public anatomy was a formal, ceremonial event. Girolamo Fabrici, the leading anatomist, gave a philosophical presentation of his research, a presentation organized by topic rather than by the gradual dissection of corpses. For medical students, the annual anatomy and the theater itself encouraged silence, obedience, and docility, reinforcing the virtues that permeated the late humanist environment of Renaissance Padua.

  2. Virtual Institute on Human Behavior Representation (Institut virtuel de representation du comportement humain)

    DTIC Science & Technology

    2010-06-01

    providing research cost savings and improved international research collaboration. The third finding is that the virtual institute concept is an...advisable means for conducting international , multi-cultural research in human behavior modeling. As a first step, meetings were held to discuss technical...également très prometteur quant à la réalisation d’économies et l’amélioration de la collaboration internationale dans le domaine de la recherche. La

  3. Human Behavior Representation in Constructive Simulation (La representation du comportement humain dans la simulation constructive)

    DTIC Science & Technology

    2009-09-01

    Cognitive Processes 5-8 5.4.1 Memory 5-8 5.4.1.1 Episodic Memory 5-8 5.4.1.2 Short Term Memory 5-9 5.4.1.3 Semantic Memory 5-10 5.4.1.4...Prospective Memory 5-11 5.4.1.5 Categorization 5-11 5.4.1.6 Learning 5-12 5.4.2 Reasoning and Thinking 5-13 5.4.3 Judgment and Choice 5-17 5.4.4...BCDMEM Bind Cue Decide Model of Episodic Memory BDI Belief, Desire, Intent BRAHMS Business Redesign Agent-based Holistic Modeling System BRIMS

  4. Human Behaviour Representation in Constructive Modelling (Representation du comportement humain dans des modelisations creatives)

    DTIC Science & Technology

    2009-09-01

    aspects of Effects Based Operations and non-kinetic warfare. The second keynote presentation, by Mr. Mike Greenley , CAE Inc. provided an industry...faite par Mr. Mike Greenley , de CAE Inc., a donné le point de vue industriel, en indiquant le besoin pour une approche des bons usages de la...Drive Suite 200 Kanata, Ontario K2K 3G7 CANADA Presenter: Mr. Mike Greenley Vice President Modelling and Simulation CAE Inc. 8585 Côte de

  5. Human Behaviour Representation in Constructive Modelling (Representation du comportement humain dans des modelisations creatives)

    DTIC Science & Technology

    2009-09-01

    Operations and non-kinetic warfare. The second keynote presentation, by Mr. Mike Greenley , CAE Inc. provided an industry perspective, noting the need for...aspects humains des opérations basées sur les effets et des actions de combats non cinétiques. La seconde présentation faite par Mr. Mike Greenley , de...K2K 3G7 CANADA Presenter: Mr. Mike Greenley Vice President Modelling and Simulation CAE Inc. 8585 Côte de Liesse Saint-Laurent, Québec H4T

  6. Comportement instationnaire des thermoéléments à effet Peltier multi-étages

    NASA Astrophysics Data System (ADS)

    Monchoux, F.; Zély, D.; Cordier, A.

    1995-01-01

    The analysis of thermoelectric phenomena is possible based on non-equilibrium thermodynamics. Integration of the thermal balance equation leads to an analytical solution for the non-stationnary behaviour. The influence to Thomson effect is commmented. The model, introduced in the complete software TRNSYS, permits the modelling of complex systems including such elements in their thermal regulation. La thermodynamique des processus irréversibles permet l'analyse des phénomènes thermoélectriques. Par intégration de l'équation de bilan thermique, on a obtenu une solution analytique pour le régime non stationnaire donnant la température en tous points et le flux absorbé. On a analysé l'influence de l'effet Thomson. Le modèle a été inclu dans le code plus général TRNSYS qui permet la modélisation de systèmes complexes.

  7. Experimental Concepts for Testing Seismic Hazard Models

    NASA Astrophysics Data System (ADS)

    Marzocchi, W.; Jordan, T. H.

    2015-12-01

    Seismic hazard analysis is the primary interface through which useful information about earthquake rupture and wave propagation is delivered to society. To account for the randomness (aleatory variability) and limited knowledge (epistemic uncertainty) of these natural processes, seismologists must formulate and test hazard models using the concepts of probability. In this presentation, we will address the scientific objections that have been raised over the years against probabilistic seismic hazard analysis (PSHA). Owing to the paucity of observations, we must rely on expert opinion to quantify the epistemic uncertainties of PSHA models (e.g., in the weighting of individual models from logic-tree ensembles of plausible models). The main theoretical issue is a frequentist critique: subjectivity is immeasurable; ergo, PSHA models cannot be objectively tested against data; ergo, they are fundamentally unscientific. We have argued (PNAS, 111, 11973-11978) that the Bayesian subjectivity required for casting epistemic uncertainties can be bridged with the frequentist objectivity needed for pure significance testing through "experimental concepts." An experimental concept specifies collections of data, observed and not yet observed, that are judged to be exchangeable (i.e., with a joint distribution independent of the data ordering) when conditioned on a set of explanatory variables. We illustrate, through concrete examples, experimental concepts useful in the testing of PSHA models for ontological errors in the presence of aleatory variability and epistemic uncertainty. In particular, we describe experimental concepts that lead to exchangeable binary sequences that are statistically independent but not identically distributed, showing how the Bayesian concept of exchangeability generalizes the frequentist concept of experimental repeatability. We also address the issue of testing PSHA models using spatially correlated data.

  8. Experimental design in chemistry: A tutorial.

    PubMed

    Leardi, Riccardo

    2009-10-12

    In this tutorial the main concepts and applications of experimental design in chemistry will be explained. Unfortunately, nowadays experimental design is not as known and applied as it should be, and many papers can be found in which the "optimization" of a procedure is performed one variable at a time. Goal of this paper is to show the real advantages in terms of reduced experimental effort and of increased quality of information that can be obtained if this approach is followed. To do that, three real examples will be shown. Rather than on the mathematical aspects, this paper will focus on the mental attitude required by experimental design. The readers being interested to deepen their knowledge of the mathematical and algorithmical part can find very good books and tutorials in the references [G.E.P. Box, W.G. Hunter, J.S. Hunter, Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building, John Wiley & Sons, New York, 1978; R. Brereton, Chemometrics: Data Analysis for the Laboratory and Chemical Plant, John Wiley & Sons, New York, 1978; R. Carlson, J.E. Carlson, Design and Optimization in Organic Synthesis: Second Revised and Enlarged Edition, in: Data Handling in Science and Technology, vol. 24, Elsevier, Amsterdam, 2005; J.A. Cornell, Experiments with Mixtures: Designs, Models and the Analysis of Mixture Data, in: Series in Probability and Statistics, John Wiley & Sons, New York, 1991; R.E. Bruns, I.S. Scarminio, B. de Barros Neto, Statistical Design-Chemometrics, in: Data Handling in Science and Technology, vol. 25, Elsevier, Amsterdam, 2006; D.C. Montgomery, Design and Analysis of Experiments, 7th edition, John Wiley & Sons, Inc., 2009; T. Lundstedt, E. Seifert, L. Abramo, B. Thelin, A. Nyström, J. Pettersen, R. Bergman, Chemolab 42 (1998) 3; Y. Vander Heyden, LC-GC Europe 19 (9) (2006) 469].

  9. Experimental investigation of the iodine partition coefficient

    SciTech Connect

    Kelly, J.L.; Babad, C.J.; Mulder, R.U.

    1985-11-01

    Short-term values of the iodine partition coefficient (IPC) were evaluated experimentally by an air/water system over the following ranges of conditions: temperature = 25 to 70/sup 0/C, pH = 5 to 9, and iodine concentration = 10/sup -9/ to 10/sup -2/ kg iodine/m/sup 3/ H/sub 2/O. The experimental IPC values are relatively independent of temperature over the indicated range, but show a significant dependence on pH and iodine concentration. In basic solutions the short-term values are several orders of magnitude less than the true equilibrium values; in acid solutions, the differences are much less. These results are useful for predicting the disposition of iodine shortly (i.e., 1 to 10 h) after iodine has been released into an air/water environment.

  10. Experimental demonstration of composite adiabatic passage

    NASA Astrophysics Data System (ADS)

    Schraft, Daniel; Halfmann, Thomas; Genov, Genko T.; Vitanov, Nikolay V.

    2013-12-01

    We report an experimental demonstration of composite adiabatic passage (CAP) for robust and efficient manipulation of two-level systems. The technique represents a altered version of rapid adiabatic passage (RAP), driven by composite sequences of radiation pulses with appropriately chosen phases. We implement CAP with radio-frequency pulses to invert (i.e., to rephase) optically prepared spin coherences in a Pr3+:Y2SiO5 crystal. We perform systematic investigations of the efficiency of CAP and compare the results with conventional π pulses and RAP. The data clearly demonstrate the superior features of CAP with regard to robustness and efficiency, even under conditions of weakly fulfilled adiabaticity. The experimental demonstration of composite sequences to support adiabatic passage is of significant relevance whenever a high efficiency or robustness of coherent excitation processes need to be maintained, e.g., as required in quantum information technology.

  11. Strategies of cell biology experimentation in space.

    PubMed

    Cogoli, Augusto

    2004-03-01

    The purpose of this article is to inform newcomers on the most important aspects of experimentation with living cells and tissues in space laboratories and platforms. There are strong arguments that justify the efforts and investments in such activity. Experimentation in space is subject to safety and technological constraints that require considerable attention to the development of the flight protocols and of the flight instrumentation. Nevertheless to fly an experiment in space is a unique opportunity to study living systems under conditions not reproducible on Earth and it is also a contribution to human exploration of space. Thereby important progress in basic and applied science can be expected. Parallel investigations on ground with devices averaging the exposure to the gravity vector but not reproducing microgravity shall always be part of a space flight project.

  12. Experimental observation of weak non-Markovianity

    PubMed Central

    Bernardes, Nadja K.; Cuevas, Alvaro; Orieux, Adeline; Monken, C. H.; Mataloni, Paolo; Sciarrino, Fabio; Santos, Marcelo F.

    2015-01-01

    Non-Markovianity has recently attracted large interest due to significant advances in its characterization and its exploitation for quantum information processing. However, up to now, only non-Markovian regimes featuring environment to system backflow of information (strong non-Markovianity) have been experimentally simulated. In this work, using an all-optical setup we simulate and observe the so-called weak non-Markovian dynamics. Through full process tomography, we experimentally demonstrate that the dynamics of a qubit can be non-Markovian despite an always increasing correlation between the system and its environment which, in our case, denotes no information backflow. We also show the transition from the weak to the strong regime by changing a single parameter in the environmental state, leading us to a better understanding of the fundamental features of non-Markovianity. PMID:26627910

  13. Numerical and experimental investigations on cavitation erosion

    NASA Astrophysics Data System (ADS)

    Fortes Patella, R.; Archer, A.; Flageul, C.

    2012-11-01

    A method is proposed to predict cavitation damage from cavitating flow simulations. For this purpose, a numerical process coupling cavitating flow simulations and erosion models was developed and applied to a two-dimensional (2D) hydrofoil tested at TUD (Darmstadt University of Technology, Germany) [1] and to a NACA 65012 tested at LMH-EPFL (Lausanne Polytechnic School) [2]. Cavitation erosion tests (pitting tests) were carried out and a 3D laser profilometry was used to analyze surfaces damaged by cavitation [3]. The method allows evaluating the pit characteristics, and mainly the volume damage rates. The paper describes the developed erosion model, the technique of cavitation damage measurement and presents some comparisons between experimental results and numerical damage predictions. The extent of cavitation erosion was correctly estimated in both hydrofoil geometries. The simulated qualitative influence of flow velocity, sigma value and gas content on cavitation damage agreed well with experimental observations.

  14. Experimental investigation of bifurcation induced bandgap reconfiguration

    NASA Astrophysics Data System (ADS)

    Bernard, Brian P.; Mazzoleni, Michael J.; Garraud, Nicolas; Arnold, David P.; Mann, Brian P.

    2014-08-01

    By applying an asymmetric on-site restoring force in a 1D chain of oscillators, we demonstrate experimentally that a morphing in the bandgap structure or passive bandgap reconfiguration can be triggered by an increase in environmental excitation amplitude. Recent studies on wave propagation have focused on new capabilities and behaviors resulting from intrinsic nonlinearities. This paper details a bistable experimental design that achieves amplitude dependent filtering through passive bandgap reconfiguration, which is triggered by a bifurcation. The system studied comprises a 1D chain of axially aligned pendulums in dimer unit cells with geometrically nonlinear nearest neighbor coupling where bistability is induced through repulsive magnets. When the bistability is asymmetric, each potential well has a different linear spectra. Though this paper uses mechanically coupled oscillators as an example, the phenomenon itself could be used in any wave propagation media where asymmetric bistability can be implemented.

  15. In vitro experimental investigation of voice production

    PubMed Central

    Horáčcek, Jaromír; Brücker, Christoph; Becker, Stefan

    2012-01-01

    The process of human phonation involves a complex interaction between the physical domains of structural dynamics, fluid flow, and acoustic sound production and radiation. Given the high degree of nonlinearity of these processes, even small anatomical or physiological disturbances can significantly affect the voice signal. In the worst cases, patients can lose their voice and hence the normal mode of speech communication. To improve medical therapies and surgical techniques it is very important to understand better the physics of the human phonation process. Due to the limited experimental access to the human larynx, alternative strategies, including artificial vocal folds, have been developed. The following review gives an overview of experimental investigations of artificial vocal folds within the last 30 years. The models are sorted into three groups: static models, externally driven models, and self-oscillating models. The focus is on the different models of the human vocal folds and on the ways in which they have been applied. PMID:23181007

  16. Public perceptions of animal experimentation across Europe.

    PubMed

    von Roten, Fabienne Crettaz

    2013-08-01

    The goal of this article is to map out public perceptions of animal experimentation in 28 European countries. Postulating cross-cultural differences, this study mixes country-level variables (from the Eurostat database) and individual-level variables (from Eurobarometer Science and Technology 2010). It is shown that experimentation on animals such as mice is generally accepted in European countries, but perceptions are divided on dogs and monkeys. Between 2005 and 2010, we observe globally a change of approval on dogs and monkeys, with a significant decrease in nine countries. Multilevel analysis results show differences at country level (related to a post-industrialism model) and at individual level (related to gender, age, education, proximity and perceptions of science and the environment). These results may have consequences for public perceptions of science and we call for more cross-cultural research on press coverage of animal research and on the level of public engagement of scientists doing animal research.

  17. Experimental Performance of a Novel Trochoidal Propeller

    NASA Astrophysics Data System (ADS)

    Roesler, Bernard; Epps, Brenden

    2015-11-01

    In the quest for energy efficiency in marine transportation, a promising marine propulsor concept is the trochoidal propeller. We have designed and tested a novel trochoidal propeller using a sinusoidal blade pitch function. The main results presented are measurements of thrust and torque, as well as the calculated efficiency, for a range of advance coefficients. The experimental data show narrow 95% confidence bounds, demonstrating high accuracy and repeatability in the experimental methods. We compare our sinusoidal-pitch trochoidal propeller with prior cross-flow propellers, as well as a representative screw propeller. While the efficiency of our propeller exceeds that of the cycloidal-pitch trochoidal propeller, it is slightly lower than the efficiencies of the other propellers considered. We also present a theoretical model that can be used to further explore and optimize such trochoidal propellers, leading to new avenues for improvements in marine propulsion systems.

  18. Experimental nuclear reaction data collection EXFOR

    SciTech Connect

    Semkova, V.; Otuka, N.; Simakov, S. P.; Zerkin, V.

    2011-07-01

    The International Network of Nuclear Reaction Data Centres (NRDC) constitutes a worldwide cooperation of 14 nuclear data centres. The main activity of the NRDC Network is collection and compilation of experimental nuclear reaction cross section data and the related bibliographic information in the EXFOR and CINDA databases as well as dissemination of nuclear reaction data and associated documentation to users. The database contains information and numerical data from more than about 19000 experiments consisting of more than 140000 datasets. EXFOR is kept up to date by constantly adding newly published experimental information. Tools developed for data dissemination utilise modern database technologies with fast online capabilities over the Internet. Users are provided with sophisticated search options, a user-friendly retrieval interface for downloading data in different formats, and additional output options such as improved data plotting capabilities. The present status of the EXFOR database will be presented together with the latest development for data access and retrieval. (authors)

  19. Human shank experimental investigation and computer simulation

    NASA Astrophysics Data System (ADS)

    Krasnoschekov, Viktor V.; Maslov, Leonid B.

    2000-01-01

    A new combined approach to analyze a physiological state of the human shank is developed. Investigated vibration research complex records resonance curve of the shank tissues automatically for different kinds of vibration excitation and for various positions of the foot. A special computer model is implemented for the estimation of the experimental data, for a priori prognosis of the bio-object behavior and its dynamic characteristics in the case of various kinds and of different degrees of injury. The method is described by the viscous-elasticity non-homogeneous 1D continuum equation. It is solved by finite element method. The problem in shank cross-section is solved by boundary element method. The analysis of computer simulated resonance curves makes it possible to understand the experimental data correctly and to check the diagnostic criteria of the injury.

  20. Experimental level densities of atomic nuclei

    DOE PAGES

    Guttormsen, M.; Aiche, M.; Bello Garrote, F. L.; ...

    2015-12-23

    It is almost 80 years since Hans Bethe described the level density as a non-interacting gas of protons and neutrons. In all these years, experimental data were interpreted within this picture of a fermionic gas. However, the renewed interest of measuring level density using various techniques calls for a revision of this description. In particular, the wealth of nuclear level densities measured with the Oslo method favors the constant-temperature level density over the Fermi-gas picture. Furthermore, trom the basis of experimental data, we demonstrate that nuclei exhibit a constant-temperature level density behavior for all mass regions and at least upmore » to the neutron threshold.« less

  1. Helicopter impulsive noise: Theoretical and experimental status

    NASA Technical Reports Server (NTRS)

    Schmitz, F. H.; Yu, Y. H.

    1983-01-01

    The theoretical and experimental status of helicopter impulsive noise is reviewed. The two major source mechanisms of helicopter impulsive noise are addressed: high-speed impulsive noise and blade-vortex interaction impulsive noise. A thorough physical explanation of both generating mechanism is presented together with model and full-scale measurements of the phenomena. Current theoretical prediction methods are compared with experimental findings of isolated rotor tests. The noise generating mechanism of high speed impulsive noise are fairly well understood - theory and experiment compare nicely over Mach number ranges typical of today's helicopters. For the case of blade-vortex interaction noise, understanding of noise generating mechanisms and theoretical comparison with experiment are less satisfactory. Several methods for improving theory-experiment are suggested.

  2. Improving the physiological realism of experimental models.

    PubMed

    Vinnakota, Kalyan C; Cha, Chae Y; Rorsman, Patrik; Balaban, Robert S; La Gerche, Andre; Wade-Martins, Richard; Beard, Daniel A; Jeneson, Jeroen A L

    2016-04-06

    The Virtual Physiological Human (VPH) project aims to develop integrative, explanatory and predictive computational models (C-Models) as numerical investigational tools to study disease, identify and design effective therapies and provide an in silico platform for drug screening. Ultimately, these models rely on the analysis and integration of experimental data. As such, the success of VPH depends on the availability of physiologically realistic experimental models (E-Models) of human organ function that can be parametrized to test the numerical models. Here, the current state of suitable E-models, ranging from in vitro non-human cell organelles to in vivo human organ systems, is discussed. Specifically, challenges and recent progress in improving the physiological realism of E-models that may benefit the VPH project are highlighted and discussed using examples from the field of research on cardiovascular disease, musculoskeletal disorders, diabetes and Parkinson's disease.

  3. Mesothelioma in man and experimental animals.

    PubMed Central

    Kannerstein, M; Churg, J

    1980-01-01

    Asbestos has been established as the cause of most cases of diffuse malignant mesothelioma occurring in the industrialized world. The morphology of mesothelioma may be complex, and the employment of chemical, histochemical and ultrastructural studies are often helpful in identification. Diagnostic difficulties may to some degree blur the extent of its prevalence and reliance on exposure history may not reveal its association with asbestos. Reference panels can be useful in assessing the former and analysis of lung tissue asbestos content may help to clarify the latter, especially in the low dose range. Electron microscopy may prove to be of assistance in this respect, possibly with particular attention to the peripheral areas of the lung. Animal experimentation has supported epidemiologic conclusions and revealed the phenomenon of fiber carcinogenesis. The morphology of mesothelioma in experimental animals is very similar to that in humans, including ultrastructural and biochemical features. PMID:6993202

  4. Helium release during shale deformation: Experimental validation

    NASA Astrophysics Data System (ADS)

    Bauer, Stephen J.; Gardner, W. Payton; Heath, Jason E.

    2016-07-01

    This work describes initial experimental results of helium tracer release monitoring during deformation of shale. Naturally occurring radiogenic 4He is present in high concentration in most shales. During rock deformation, accumulated helium could be released as fractures are created and new transport pathways are created. We present the results of an experimental study in which confined reservoir shale samples, cored parallel and perpendicular to bedding, which were initially saturated with helium to simulate reservoir conditions, are subjected to triaxial compressive deformation. During the deformation experiment, differential stress, axial, and radial strains are systematically tracked. Release of helium is dynamically measured using a helium mass spectrometer leak detector. Helium released during deformation is observable at the laboratory scale and the release is tightly coupled to the shale deformation. These first measurements of dynamic helium release from rocks undergoing deformation show that helium provides information on the evolution of microstructure as a function of changes in stress and strain.

  5. Shock unsteadiness creation and propagation: experimental analysis

    NASA Astrophysics Data System (ADS)

    Benay, R.; Alaphilippe, M.; Severac, N.

    2012-09-01

    The possibility of creating unsteady distortions of the tip shock by waves emitted from an aircraft is assessed experimentally. The model chosen is a cylindrical fore body equipped with a spike. This configuration is known for generating an important level of unsteadiness around the spike in supersonic regime. The wind tunnel Mach number is equal to 2. The experiments show that waves emitted from this source propagate along the tip shock and interact with it. It is then assessed that this interaction produces a periodic distortion of the shock that propagates to the external flow. Unsteady pressure sensors, high speed schlieren films, hot wire probing and laser Doppler velocimetry are used as complementary experimental means. The final result is a coherent representation of the complex mechanism of wave propagation that has been evidenced. The principle of creating unsteady shock deformation by onboard equipments could be examined as a possibly promising method of sonic boom control.

  6. Association between postmenopausal osteoporosis and experimental periodontitis.

    PubMed

    Luo, Kai; Ma, Souzhi; Guo, Jianbin; Huang, Yongling; Yan, Fuhua; Xiao, Yin

    2014-01-01

    To investigate the correlation between postmenopausal osteoporosis (PMO) and the pathogenesis of periodontitis, ovariectomized rats were generated and the experimental periodontitis was induced using a silk ligature. The inflammatory factors and bone metabolic markers were measured in the serum and periodontal tissues of ovariectomized rats using an automatic chemistry analyzer, enzyme-linked immunosorbent assays, and immunohistochemistry. The bone mineral density of whole body, pelvis, and spine was analyzed using dual-energy X-ray absorptiometry and image analysis. All data were analyzed using SPSS 13.0 statistical software. It was found that ovariectomy could upregulate the expression of interleukin- (IL-)6, the receptor activator of nuclear factor- κB ligand (RANKL), and osteoprotegerin (OPG) and downregulate IL-10 expression in periodontal tissues, which resulted in progressive alveolar bone loss in experimental periodontitis. This study indicates that changes of cytokines and bone turnover markers in the periodontal tissues of ovariectomized rats contribute to the damage of periodontal tissues.

  7. Experimental Manufacture of Paper for War Maps

    PubMed Central

    Weber, Charles G.; Shaw, Merle B.

    2000-01-01

    Early in World War II, a new map paper was developed that greatly improved the quality and performance of war maps. The National Bureau of Standards cooperated in the development and, subsequently, determined by experimental manufacture how to make the paper from commercially available raw materials. The best results were obtained in experimental manufacture by using fiber furnishes of 100-percent strong bleached sulfate pulps with the addition of melamine-formaldehyde resin to increase the wet strength and titanium dioxide to produce the desired capacity. It was essential that the beating be very carefully controlled to preserve the maximum fiber strength. The most critical requirements from a manufacturing standpoint were very high resistance to tear, high wet tensile strength, high opacity, and good smoothness. A moderate degree of wildness was not objectionable. The data obtained by experiments were applied to initiate the commercial production of the new paper to meet unprecedented tonnage requirements. PMID:27551643

  8. Experimental Robust Control of Structural Acoustic Radiation

    NASA Technical Reports Server (NTRS)

    Cox, David E.; Gibbs, Gary P.; Clark, Robert L.; Vipperman, Jeffrey S.

    1998-01-01

    This work addresses the design and application of robust controllers for structural acoustic control. Both simulation and experimental results are presented. H(infinity) and mu-synthesis design methods were used to design feedback controllers which minimize power radiated from a panel while avoiding instability due to unmodeled dynamics. Specifically, high order structural modes which couple strongly to the actuator-sensor path were poorly modeled. This model error was analytically bounded with an uncertainty model, which allowed controllers to be designed without artificial limits on control effort. It is found that robust control methods provide the control designer with physically meaningful parameters with which to tune control designs and can be very useful in determining limits of performance. Experimental results also showed, however, poor robustness properties for control designs with ad-hoc uncertainty models. The importance of quantifying and bounding model errors is discussed.

  9. Experimental studies on waste paper pulp biodegradation.

    PubMed

    Sharma, R; Sharma, D; Rao, K S; Jain, R C

    2002-07-01

    In continuation of their studies on Biodegradation of cellulosic waste materials, the authors have presented their experimental data on biodegradation on waste paper pulp. Greater efficiency in the cow dung and M3 culture experimental setups have been pointed out and discussed. Necessity of detailed data evaluation of temperature, pH, dry weight, cellulose, protein, carbohydrate, Nitrate, Phosphate & Potassium levels is suggested. Derivation of %, absolute and increase/decrease % of BOO, COD and VS have been pointed out for the first time in solid waste Biodegradation. Further data evaluation and derivation of critical reaction rate kinetics have been recommended for further studies in solid waste-degradation to achieve quicker Bioconversion of cellulosic wastes into compost.

  10. Calcium release from experimental dental materials.

    PubMed

    Okulus, Zuzanna; Buchwald, Tomasz; Voelkel, Adam

    2016-11-01

    The calcium release from calcium phosphate-containing experimental dental restorative materials was examined. The possible correlation of ion release with initial calcium content, solubility and degree of curing (degree of conversion) of examined materials was also investigated. Calcium release was measured with the use of an ion-selective electrode in an aqueous solution. Solubility was established by the weighing method. Raman spectroscopy was applied for the determination of the degree of conversion, while initial calcium content was examined with the use of energy-dispersive spectroscopy. For examined materials, the amount of calcium released was found to be positively correlated with solubility and initial calcium content. It was also found that the degree of conversion does not affect the ability of these experimental composites to release calcium ions.

  11. Experimental aerothermodynamic research of hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Cleary, Joseph W.

    1987-01-01

    The 2-D and 3-D advance computer codes being developed for use in the design of such hypersonic aircraft as the National Aero-Space Plane require comparison of the computational results with a broad spectrum of experimental data to fully assess the validity of the codes. This is particularly true for complex flow fields with control surfaces present and for flows with separation, such as leeside flow. Therefore, the objective is to provide a hypersonic experimental data base required for validation of advanced computational fluid dynamics (CFD) computer codes and for development of more thorough understanding of the flow physics necessary for these codes. This is being done by implementing a comprehensive test program for a generic all-body hypersonic aircraft model in the NASA/Ames 3.5 foot Hypersonic Wind Tunnel over a broad range of test conditions to obtain pertinent surface and flowfield data. Results from the flow visualization portion of the investigation are presented.

  12. Natural compounds as anticancer agents: Experimental evidence

    PubMed Central

    Wang, Jiao; Jiang, Yang-Fu

    2012-01-01

    Cancer prevention research has drawn much attention worldwide. It is believed that some types of cancer can be prevented by following a healthy life style. Cancer chemoprevention by either natural or synthetic agents is a promising route towards lowering cancer incidence. In recent years, the concept of cancer chemoprevention has evolved greatly. Experimental studies in animal models demonstrate that the reversal or suppression of premalignant lesions by chemopreventive agents is achievable. Natural occurring agents such as dietary phytochemicals, tea polyphenols and resveratrol show chemopreventive activity in animal models. Moreover, clinical trials for testing the safety and efficacy of a variety of natural agents in preventing or treating human malignancy have been ongoing. Here, we summarize experimental data on the chemopreventive or tumor suppressive effects of several natural compounds including curcumin, (-)-epigallocatechin-3-gallate, resveratrol, indole-3-carbinol, and vitamin D. PMID:24520533

  13. Recent Experimental Progress on Surrogate Reactions

    NASA Astrophysics Data System (ADS)

    Beausang, Cornelius

    2014-09-01

    Reactions on unstable nuclei are important in a wide variety of nuclear physics scenarios. Cross sections for neutron (or light charged particle) induced reactions on target nuclei spanning the chart of the nuclei are important for nuclear astrophysics (r-process, s-process rp- and p-processes etc.), for nuclear energy generation and for national security applications. Many such reactions occur on short-lived unstable nuclei. Even with the present generation of radioactive beam facilities, many such reactions are difficult, if not impossible, to measure directly. For these reactions, often the surrogate reaction technique provides the only option to provide some experimental guidance for the calculations. The experimental and theoretical techniques required are described in some detail in the recent review article by Escher et al.. Originally introduced in the 1970's the last decade has seen a resurgence of interest in the surrogate technique. Various ratio techniques, external, internal and hybrid, have been developed to minimize the effect of target contamination. In the actinide region, a large number of surrogate (n,f) cross sections have been measured. In general, these show agreement to within 5--10%, with directly measured (n,f) data where these data exist (benchmarking), for equivalent neutron energies ranging from ~100 keV up to tens of MeV. For (n, γ) reactions, measurements have been attempted for select nuclei in various mass regions (A ~ 90, 150 and 235) and for these the agreement with directly measured data is less good. The various experimental techniques employed will be described as well as the current state of the experimental data. Some future directions will be described. Reactions on unstable nuclei are important in a wide variety of nuclear physics scenarios. Cross sections for neutron (or light charged particle) induced reactions on target nuclei spanning the chart of the nuclei are important for nuclear astrophysics (r-process, s

  14. Experimental implementation of maximally synchronizable networks

    NASA Astrophysics Data System (ADS)

    Sevilla-Escoboza, R.; Buldú, J. M.; Boccaletti, S.; Papo, D.; Hwang, D.-U.; Huerta-Cuellar, G.; Gutiérrez, R.

    2016-04-01

    Maximally synchronizable networks (MSNs) are acyclic directed networks that maximize synchronizability. In this paper, we investigate the feasibility of transforming networks of coupled oscillators into their corresponding MSNs. By tuning the weights of any given network so as to reach the lowest possible eigenratio λN /λ2, the synchronized state is guaranteed to be maintained across the longest possible range of coupling strengths. We check the robustness of the resulting MSNs with an experimental implementation of a network of nonlinear electronic oscillators and study the propagation of the synchronization errors through the network. Importantly, a method to study the effects of topological uncertainties on the synchronizability is proposed and explored both theoretically and experimentally.

  15. Description of Liquid Nitrogen Experimental Test Facility

    NASA Technical Reports Server (NTRS)

    Jurns, John M.; Jacobs, Richard E.; Saiyed, Naseem H.

    1991-01-01

    The Liquid Nitrogen Test Facility is a unique test facility for ground-based liquid nitrogen experimentation. The test rig consists of an insulated tank of approximately 12.5 cubic ft in volume, which is supplied with liquid nitrogen from a 300 gal dewar via a vacuum jacketed piping system. The test tank is fitted with pressure and temperature measuring instrumentation, and with two view ports which allow visual observation of test conditions. To demonstrate the capabilities of the facility, the initial test program is briefly described. The objective of the test program is to measure the condensation rate by injecting liquid nitrogen as a subcooled spray into the ullage of a tank 50 percent full of liquid nitrogen at saturated conditions. The condensation rate of the nitrogen vapor on the subcooled spray can be analytically modeled, and results validated and corrected by experimentally measuring the vapor condensation on liquid sprays.

  16. Mechanical diode: Comparing numerical and experimental characterizations

    SciTech Connect

    Sagartz, M.J.; Segalman, D.; Simmermacher, T.

    1998-02-01

    In this introductory work, joint compliance is studied in both a numerical and experimental setting. A simple bolted interface is used as the test article and compliance is measured for the joint in both compression and in tension. This simple interface is shown to exhibit a strong non-linearity near the transition from compression to tension (or vice-versa). Modeling issues pertaining to numerically solving for the compliance are addressed. It is shown that the model predictions, in spite of convergence being very sensitive to numerical artifacts of the interface model, are in good agreement with experimentally measured strains and joint compliances. The joint behavior is a mechanical analogy to a diode, i.e., in compression, the joint is very stiff, acting almost as a rigid link, while in tension the joint is relatively soft, acting as a spring.

  17. (Hyperfine experimental investigation of zirconia ceramics)

    SciTech Connect

    Not Available

    1992-01-01

    This research program has encompassed a broad investigation of microscopic structure and point defect properties in insulating materials and some recent exploratory work on semiconductors. The major experimental technique is perturbed angular correlation (PAC) spectroscopy. Our research provides information about the microscopic structure, nucleation, and equilibrium of structural phases in materials under investigation. We have studied phase equilibria in monoclinic, tetragonal, and cubic zirconia in the past and have recently begun more detailed investigation of high-temperature anomalies in monoclinic zirconia and tetragonal stabilized zirconia. We also have found a number of instances where the indium PAC probe has detected subtle phase changes, small precipitate formation, and other phase behavior that are difficult to detect by conventional diffraction methods. The PAC experimental technique is described briefly in section 2, and recent research is reviewed in section 3.

  18. Theoretical and Experimental Study of Thermoacoustic Engines

    DTIC Science & Technology

    1992-12-01

    61153N11 uri5005 11. TITLE (Include Security Classification) Theoretical and Experimental Study of Thermoacoustic Engines 12 . PERSONAL AUTHOR(S) Richard...9/30 92/ 12 /31 16. SUPPLEMENTARY NOTATION 17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD...central portion. Copper rings of thickness 3.2 mm, inner radius 4.32 cm, and outer radius of 12 cm were supported between the ends of the ceramic piece

  19. Theoretical and experimental studies of elementary particles

    NASA Astrophysics Data System (ADS)

    Bodek, A.; Ferbel, T.; Melissinos, A. C.; Olsen, S. L.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C. R.; Rajeev, S. G.; Okubo, S.

    This report discusses fixed target experimentation at Fermilab; the D-zero collider experiment at Fermilab; deep inelastic lepton nucleon scattering; non-accelerator experiments and non-linear quantum electrodynamics (QED); the AMY experiment at TRISTAN and other activities at KEK; the collider detector at Fermilab; laser switched linac; preparations for experiments at the SSC; search for massive stable particles; and the Advanced Study Institute on techniques and concepts of high energy physics.

  20. Experimental generation of complex noisy photonic entanglement

    NASA Astrophysics Data System (ADS)

    Dobek, K.; Karpiński, M.; Demkowicz-Dobrzański, R.; Banaszek, K.; Horodecki, P.

    2013-02-01

    We present an experimental scheme based on spontaneous parametric down-conversion to produce multiple-photon pairs in maximally entangled polarization states using an arrangement of two type-I nonlinear crystals. By introducing correlated polarization noise in the paths of the generated photons we prepare mixed-entangled states whose properties illustrate fundamental results obtained recently in quantum information theory, in particular those concerning bound entanglement and privacy.

  1. Leveraging the Cloud for Integrated Network Experimentation

    DTIC Science & Technology

    2014-03-01

    6 2.2.1.2 OPNET . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.2.1.3 Simulation Summary...and scope of the review. The Introduction section is followed by a review of network experimentation techniques used by NS-3, OPNET , Emulab, Planetlab...open source simulator, and the most popular proprietary simulator, ns-3 and OPNET respectively. 2.2.1.1 NS-3. One of the most popular open source

  2. Sensor capabilities for the HERMIES experimental robot

    SciTech Connect

    Killough, S.M.; Hamel, W.R.

    1988-01-01

    The Center for Engineering Systems Advanced Research at the Oak Ridge National Laboratory has developed an experimental robot, the HERMIES, to test artificial intelligence concepts. This paper describes the capabilities provided for navigation and control. The authors conclude that the sensor suite, which enables the robot to recognize, locate, and grasp objects, makes HERMIES IIB a powerful tool for robotics and artificial intelligence research. 7 refs., 11 figs.

  3. Experimental measurements on a single sweeping jet

    NASA Astrophysics Data System (ADS)

    Hirsch, Damian; Graff, Emilio; Gharib, Morteza

    2014-11-01

    ``Sweeping jets'' proved their effectiveness as Active Flow Control (AFC) actuators in improving the performance of vertical tails of generic and full-scale models. To gain further knowledge about the fundamental flow physics, the jets were investigated experimentally. The influence of a single jet on its surroundings was studied, especially the entrainment region. The results were compared to previous experiments to study the difference between a single isolated jet and multiple jets mounted on a vertical tail. Supported by the Boeing Company.

  4. [Bioethics and drug experimentation in hospitalized patients].

    PubMed

    Sinaccio, G; Robert, E; Sinaccio, C; Robert, E

    1993-01-01

    The authors discuss about clinical experimentation with drugs involving hospitalized subjects in consideration of four principles of Bioethics: Autonomy, Beneficence, Non Maleficence and Justice. This article explores also the problems linked to the application of good clinical practice according to the European and Italian recent rules. Human integrity, respect of patient's dignity, informed consent, correct methods, placebo, Ethics committees represent the essential basis for those researchers that intend conduct clinical trials really "with subject and not on the subject".

  5. Experimental Facilities and Modelling for Rarefied Aerodynamics

    DTIC Science & Technology

    2011-01-01

    aerodynamic forces and moments that act on an object moving in the gas . The aerodynamics of rarefied gases also investigates the flow of gases in...Originally, theoretical models for rarefied gas flows were developed in the frame of the molecular kinetic theory. Thus the first self-consistent descriptions...method [7-11]. 3.0 EXPERIMENTAL FACILITIES FOR RAREFIED FLOWS 3.1 Overview Rarefied - gas (vacuum) wind tunnel is a wind tunnel operating at low pressures

  6. Experimental system and component performance analysis

    SciTech Connect

    Peterman, K.

    1984-10-01

    A prototype dye laser flow loop was constructed to flow test large power amplifiers in Building 169. The flow loop is designed to operate at supply pressures up to 900 psig and flow rates up to 250 GPM. During the initial startup of the flow loop experimental measurements were made to evaluate component and system performance. Three candidate dye flow loop pumps and three different pulsation dampeners were tested.

  7. Experimental and Computational Characterization of Combustion Phenomena

    DTIC Science & Technology

    2006-05-01

    Fundamental Combustion Advanced Combustor Concepts Combustor Demonstration and Transition Figure 1. A design philosophy for transitioning basic...PFP UNCLASSIFIED [4] W.-W. Kim, S. Menon, and H. Mongia , “Large-Eddy Simulation of a Gas Turbine Combustor Flow,” Combust . Sci. Technol. 143, 25-62...AFRL-PR-WP-TM-2006-2131 EXPERIMENTAL AND COMPUTATIONAL CHARACTERIZATION OF COMBUSTION PHENOMENA Dr. James R. Gord Combustion Branch (AFRL

  8. Experimental Benchmarking of the Magnetized Friction Force

    SciTech Connect

    Fedotov, A. V.; Litvinenko, V. N.; Galnander, B.; Lofnes, T.; Ziemann, V.; Sidorin, A. O.; Smirnov, A. V.

    2006-03-20

    High-energy electron cooling, presently considered as essential tool for several applications in high-energy and nuclear physics, requires accurate description of the friction force. A series of measurements were performed at CELSIUS with the goal to provide accurate data needed for the benchmarking of theories and simulations. Some results of accurate comparison of experimental data with the friction force formulas are presented.

  9. EXPERIMENTAL BENCHMARKING OF THE MAGNETIZED FRICTION FORCE.

    SciTech Connect

    FEDOTOV, A.V.; GALNANDER, B.; LITVINENKO, V.N.; LOFNES, T.; SIDORIN, A.O.; SMIRNOV, A.V.; ZIEMANN, V.

    2005-09-18

    High-energy electron cooling, presently considered as essential tool for several applications in high-energy and nuclear physics, requires accurate description of the friction force. A series of measurements were performed at CELSIUS with the goal to provide accurate data needed for the benchmarking of theories and simulations. Some results of accurate comparison of experimental data with the friction force formulas are presented.

  10. Animal experimentation--a personal view.

    PubMed

    Gershoff, Stanley N

    2009-02-01

    Disagreement about the use of animals in biomedical research has resulted in absurd positions by both sides. Increasingly, some zealots against animal experimentation have resorted to violence or other illegal acts to support their points of view. The value of animal research in providing better health for man and animals is incontrovertible. This is illustrated by references to animal research in the field of nutrition.

  11. C-2U Experimental Transport Analysis

    NASA Astrophysics Data System (ADS)

    Trask, Erik; Beall, M.; Bolte, N.; Deng, B.; Douglass, J.; Gota, H.; Granstedt, E.; Gupta, D.; Osin, D.; Roche, T.; Zhai, K.; TAE Team

    2016-10-01

    Upgrades of the experimental facility at Tri Alpha Energy have led to record Field Reversed Configuration (FRC) performance on the C-2U device. Modifications to magnetic field characteristics and increases in neutral beam power were critical drivers in achieving sustained plasma targets for greater than 5ms. 0D power balance calculations detailing loss channel characteristics and plasma timescales will be presented demonstrating substantial improvements in equilibrium and transport parameters. Tri Alpha Energy, Inc.

  12. Extracting model equations from experimental data

    NASA Astrophysics Data System (ADS)

    Friedrich, R.; Siegert, S.; Peinke, J.; Lück, St.; Siefert, M.; Lindemann, M.; Raethjen, J.; Deuschl, G.; Pfister, G.

    2000-06-01

    This letter wants to present a general data-driven method for formulating suitable model equations for nonlinear complex systems. The method is validated in a quantitative way by its application to experimentally found data of a chaotic electric circuit. Furthermore, the results of an analysis of tremor data from patients suffering from Parkinson's disease, from essential tremor, and from normal subjects with physiological tremor are presented, discussed and compared. They allow a distinction between the different forms of tremor.

  13. Experimental Searches for Dark Sector Phenomena

    NASA Astrophysics Data System (ADS)

    Alexander, Jim

    2017-01-01

    We summarize the state of experimental searches for Dark Sector dark matter, focussing on current and planned experiments that look for evidence of dark photon production. The accessible dark photon masses range from about 1 MeV to about 1 GeV, cover several orders of magnitude in the dimensionless coupling constant to normal matter. Experiments include fixed target and collider experiments, seeking inclusive or exclusive final state signatures, produced from either leptonic and hadronic initial states.

  14. Experimental history: swinging pendulums and melting shellac.

    PubMed

    Palmieri, Paolo

    2009-09-01

    Four hundred years ago Galileo Galilei aimed a telescope at the sky. He revolutionized astronomy. Equally revolutionary were his experiments in physics. Unlike his astronomical observations the experiments remain difficult to understand and replicate even today. Two centuries after Galileo, Augustin Coulomb demonstrated experimentally the law of electrostatic force. It has never been successfully replicated. Yet both Galileo and Coulomb were exquisite experimentalists. The fact is that revolutionary experiments in physics are never finished. They are open for investigation for generations to come.

  15. Experimental modeling of cavitation occurring at vibration

    NASA Astrophysics Data System (ADS)

    Gaynutdinova, D. F.; Modorskii, V. Ya.; Shevelev, N. A.

    2016-10-01

    The article investigates the problem of effects in two-stage centrifugal pumps due to hydro-gas-dynamic processes resulting from vibrations of design elements which are difficult to forecast. Numerical and experimental simulation of this problem was conducted. The experiment discovered cavitation effects brought about by the vibrations. The area of cavitations was plotted. Dependence of cavitation bubble concentration on amplitude and frequency of the vibrations was found.

  16. Experimental falsification of Leggett's nonlocal variable model.

    PubMed

    Branciard, Cyril; Ling, Alexander; Gisin, Nicolas; Kurtsiefer, Christian; Lamas-Linares, Antia; Scarani, Valerio

    2007-11-23

    Bell's theorem guarantees that no model based on local variables can reproduce quantum correlations. Also, some models based on nonlocal variables, if subject to apparently "reasonable" constraints, may fail to reproduce quantum physics. In this Letter, we introduce a family of inequalities, which use a finite number of measurement settings, and which therefore allow testing Leggett's nonlocal model versus quantum physics. Our experimental data falsify Leggett's model and are in agreement with quantum predictions.

  17. Experimental Observation of a Photon Bouncing Ball

    SciTech Connect

    Della Valle, G.; Ornigotti, M.; Laporta, P.; Longhi, S.; Savoini, M.; Finazzi, M.; Duo, L.; Foglietti, V.

    2009-05-08

    An optical analogue of a quantum particle bouncing on a hard surface under the influence of gravity (a quantum bouncer) is experimentally demonstrated using a circularly curved optical waveguide. Spatially resolved tunneling optical microscopy measurements of multiple beam reflections at the waveguide edge clearly show the appearance of wave packet collapses and revivals (either integer and fractional), corresponding to the full quantum regime of the quantum bouncer.

  18. How Can We Test Seesaw Experimentally?

    SciTech Connect

    Buckley, Matthew R.; Murayama, Hitoshi

    2006-06-07

    The seesaw mechanism for the small neutrino mass has been a popular paradigm, yet it has been believed that there is no way to test it experimentally. We present a conceivable outcome from future experiments that would convince us of the seesaw mechanism. It would involve a variety of data from LHC, ILC, cosmology, underground, and low-energy flavor violation experiments to establish the case.

  19. Experimenters' reference based upon Skylab experiment management

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The methods and techniques for experiment development and integration that evolved during the Skylab Program are described to facilitate transferring this experience to experimenters in future manned space programs. Management responsibilities and the sequential process of experiment evolution from initial concept through definition, development, integration, operation and postflight analysis are outlined and amplified, as appropriate. Emphasis is placed on specific lessons learned on Skylab that are worthy of consideration by future programs.

  20. Experimental Breeder Reactor I Preservation Plan

    SciTech Connect

    Julie Braun

    2006-10-01

    Experimental Breeder Reactor I (EBR I) is a National Historic Landmark located at the Idaho National Laboratory, a Department of Energy laboratory in southeastern Idaho. The facility is significant for its association and contributions to the development of nuclear reactor testing and development. This Plan includes a structural assessment of the interior and exterior of the EBR I Reactor Building from a preservation, rather than an engineering stand point and recommendations for maintenance to ensure its continued protection.

  1. Commande numérique de moteurs synchrones à aimants permanents de faible puissance

    NASA Astrophysics Data System (ADS)

    Robyns, B.; Fu, Y.; Labrique, F.; Buyse, H.

    1995-08-01

    High performance motion control with permanent magnet synchronous actuators needs complex control strategies. These control strategies lead frequently to algorithms requiring powerful microprocessors for their digital implementation. In this paper, we consider an approach of the control of small power permanent magnets synchronous actuators which allows to design and to implement control algorithms requiring only a reduced computation power, while maintaining satisfactory static and dynamic performance and a good insensitivity to perturbations and parameter uncertainties. L'actionnement électrique à hautes performances par moteurs synchrones à aimants permanents impose des stratégies de commande évoluées liées au comportement dynamique complexe de ces machines. Ces stratégies de commande conduisent fréquemment à des algorithmes dont l'implantation numérique exige des microprocesseurs ayant une puissance de calcul élevée. Dans cet article, nous développons une approche du problème de la commande des moteurs synchrones à aimants permanents de faible puissance qui permet de concevoir et d'implanter des algorithmes de commande ne nécessitant qu'une puissance de calcul réduite, tout en garantissant des performances statiques et dynamiques satisfaisantes ainsi qu'une bonne insensibilité aux perturbations agissant sur le système et aux incertitudes sur les paramètres.

  2. Experimental study of the chaotic waterwheel

    NASA Astrophysics Data System (ADS)

    Rutherford, George; Erxleben, Amy; Rosa, Epaminondas, Jr.

    2007-03-01

    The chaotic waterwheel is often given as an example of a mechanical system that can exhibit chaotic behavior. Its early demonstration by Malkus and the realization that it can be modeled by the Lorenz equations has secured it a prominent place in almost every general presentation of chaos. It seems quite surprising, then, that no experimental investigations of this textbook system have ever been published. To fill this historic gap, and to initiate an experimental study of this incredibly rich dynamic system, our lab has constructed a research-grade waterwheel consisting of a vacuum-formed polycarbonate frame in which 36 cylindrical cells are mounted on an 18 inch diameter. The wheel and its axis can be tilted, and water is fed into the top of the wheel and drains out through thin tubes at the bottom of each cell. An aluminum skirt at the wheel's periphery passes through a variable gap magnet to provide magnetic braking. Angular time series data are collected with an absolute rotary encoder. The data are smoothed and angular velocity and acceleration are calculated via fast fourier transforms. The data show quasi-uniform rotation as well as periodic and chaotic motion and agree fairly well with computer simulations of the idealized wheel equations. We will discuss differences between the experimental data and the simulation predictions as well as plans for future studies.

  3. Differential Angiogenic Regulation of Experimental Colitis

    PubMed Central

    Chidlow, John H.; Langston, Will; Greer, James J.M.; Ostanin, Dmitry; Abdelbaqi, Maisoun; Houghton, Jeffery; Senthilkumar, Annamalai; Shukla, Deepti; Mazar, Andrew P.; Grisham, Matthew B.; Kevil, Christopher G.

    2006-01-01

    Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the intestinal tract with unknown multifactorial etiology that, among other things, result in alteration and dysfunction of the intestinal microvasculature. Clinical observations of increased colon microvascular density during IBD have been made. However, there have been no reports investigating the physiological or pathological importance of angiogenic stimulation during the development of intestinal inflammation. Here we report that the dextran sodium sulfate and CD4+CD45RBhigh T-cell transfer models of colitis stimulate angiogenesis that results in increased blood vessel density concomitant with increased histopathology, suggesting that the neovasculature contributes to tissue damage during colitis. We also show that leukocyte infiltration is an obligatory requirement for the stimulation of angiogenesis. The angiogenic response during experimental colitis was differentially regulated in that the production of various angiogenic mediators was diverse between the two models with only a small group of molecules being similarly controlled. Importantly, treatment with the anti-angiogenic agent thalidomide or ATN-161 significantly reduced angiogenic activity and associated tissue histopathology during experimental colitis. Our findings identify a direct pathological link between angiogenesis and the development of experimental colitis, representing a novel therapeutic target for IBD. PMID:17148665

  4. Experimental verification of an indefinite causal order

    PubMed Central

    Rubino, Giulia; Rozema, Lee A.; Feix, Adrien; Araújo, Mateus; Zeuner, Jonas M.; Procopio, Lorenzo M.; Brukner, Časlav; Walther, Philip

    2017-01-01

    Investigating the role of causal order in quantum mechanics has recently revealed that the causal relations of events may not be a priori well defined in quantum theory. Although this has triggered a growing interest on the theoretical side, creating processes without a causal order is an experimental task. We report the first decisive demonstration of a process with an indefinite causal order. To do this, we quantify how incompatible our setup is with a definite causal order by measuring a “causal witness.” This mathematical object incorporates a series of measurements that are designed to yield a certain outcome only if the process under examination is not consistent with any well-defined causal order. In our experiment, we perform a measurement in a superposition of causal orders—without destroying the coherence—to acquire information both inside and outside of a “causally nonordered process.” Using this information, we experimentally determine a causal witness, demonstrating by almost 7 SDs that the experimentally implemented process does not have a definite causal order. PMID:28378018

  5. Experimental monitoring for the MAJORANA DEMONSTRATOR

    NASA Astrophysics Data System (ADS)

    Xu, Wenqin; MAJORANA Collaboration

    2017-01-01

    The MAJORANA DEMONSTRATOR neutrinoless double beta (0 νββ) decay experiment has instrumented two modules of high purity germanium (HPGe) detectors to search for 0 νββ decay in 76Ge. The experiment has started accumulating quality data towards its goal of demonstrating the technical feasibility and low backgrounds for a next generation Ge-based 0 νββ experiment. It is critical to extensively monitor the performance of the experimental apparatus without disturbing the blindness data-taking scheme. The experimental monitoring is composed of several stages including, for example, the live monitoring embedded in the Data-Acquisition system, onsite near-live monitoring and data production monitoring. In all stages, automatic alerting mechanisms and scheduled manual checks are implemented in a coordinated way. In this talk, we will discuss the internal management of each experimental monitoring stage and their relationships to each other. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, the Particle Astrophysics and Nuclear Physics Programs of the National Science Foundation, and Sanford Underground Research Facility.

  6. Sequential experimental design based generalised ANOVA

    SciTech Connect

    Chakraborty, Souvik Chowdhury, Rajib

    2016-07-15

    Over the last decade, surrogate modelling technique has gained wide popularity in the field of uncertainty quantification, optimization, model exploration and sensitivity analysis. This approach relies on experimental design to generate training points and regression/interpolation for generating the surrogate. In this work, it is argued that conventional experimental design may render a surrogate model inefficient. In order to address this issue, this paper presents a novel distribution adaptive sequential experimental design (DA-SED). The proposed DA-SED has been coupled with a variant of generalised analysis of variance (G-ANOVA), developed by representing the component function using the generalised polynomial chaos expansion. Moreover, generalised analytical expressions for calculating the first two statistical moments of the response, which are utilized in predicting the probability of failure, have also been developed. The proposed approach has been utilized in predicting probability of failure of three structural mechanics problems. It is observed that the proposed approach yields accurate and computationally efficient estimate of the failure probability.

  7. Experimental results from the small isochronous ring

    SciTech Connect

    Eduard Pozdeyev

    2005-05-01

    The Small Isochronous Ring (SIR) is a compact, low-energy storage ring designed to investigate the beam dynamics of high-intensity isochronous cyclotrons and synchrotrons at the transition energy. The ring was developed at Michigan State University (MSU) and has been operational since December 2003. It stores 20 keV hydrogen beams with a peak current of 10-20 microamps for up to 200 turns. The transverse and longitudinal profiles of extracted bunches are measured with an accuracy of approximately 1 mm. The high accuracy of the measurements makes the experimental data attractive for validation of multi-particle space charge codes. The results obtained in the ring show a fast growth of the energy spread induced by the space charge forces. The energy spread growth is accompanied by a breakup of the beam bunches into separated clusters that are involved in the vortex motion specific to the isochronous regime. The experimental results presented in the paper show a remarkable agreement with simulations performed with the code CYCO. In this paper, we discuss specifics of space charge effects in the isochronous regime, present results of experiments in SIR, and conduct a detailed comparison of the experimental data with results of simulations.

  8. Fetal cardiac interventions: clinical and experimental research

    PubMed Central

    Humuruola, Gulimila

    2016-01-01

    Fetal cardiac interventions for congenital heart diseases may alleviate heart dysfunction, prevent them evolving into hypoplastic left heart syndrome, achieve biventricular outcome and improve fetal survival. Candidates for clinical fetal cardiac interventions are now restricted to cases of critical aortic valve stenosis with evolving hypoplastic left heart syndrome, pulmonary atresia with an intact ventricular septum and evolving hypoplastic right heart syndrome, and hypoplastic left heart syndrome with an intact or highly restrictive atrial septum as well as fetal heart block. The therapeutic options are advocated as prenatal aortic valvuloplasty, pulmonary valvuloplasty, creation of interatrial communication and fetal cardiac pacing. Experimental research on fetal cardiac intervention involves technical modifications of catheter-based cardiac clinical interventions and open fetal cardiac bypass that cannot be applied in human fetuses for the time being. Clinical fetal cardiac interventions are plausible for midgestation fetuses with the above-mentioned congenital heart defects. The technical success, biventricular outcome and fetal survival are continuously being improved in the conditions of the sophisticated multidisciplinary team, equipment, techniques and postnatal care. Experimental research is laying the foundations and may open new fields for catheter-based clinical techniques. In the present article, the clinical therapeutic options and experimental fetal cardiac interventions are described. PMID:27279868

  9. Correlates of diuretic renography in experimental hydronephrosis

    SciTech Connect

    Kekomaeki, M.R.; Rikalainen, H.; Ruotsalainen, P.; Bertenyi, C.

    1989-02-01

    We studied the correlations between diuretic renographs and kidney function in experimental hydronephrosis in rabbits. Features of furosemide-stimulated /sup 99m/Tc-diethylenetriamine-pentaacetic acid renographs were compared to the growth rate, thirst test and endogenous creatinine clearance rate in a chronic solitary-kidney animal model. Intravenous pyelograms, done four weeks after laparotomy, left nephrectomy, bladder resection and constriction of the right pyeloureteric junction, showed signs of obstruction in all the 12 animals of the experimental group. An absent tracer washout after intravenous furosemide, found in five animals, was associated with retarded growth, isosthenuria and an abnormal creatinine clearance. In all of the other seven animals, a distinct tracer washout after intravenous furosemide was accompanied with a normal growth rate and creatinine clearance. However, no one of these seven animals had a normal ability to retain water and concentrate urine in the thirst test. We conclude that, in this experimental model, a furosemide-induced tracer washout from the kidney pelvis cannot be taken as a proof of the absence of any upper urinary tract obstruction.

  10. Experimental Supersonic Combustion Research at NASA Langley

    NASA Technical Reports Server (NTRS)

    Rogers, R. Clayton; Capriotti, Diego P.; Guy, R. Wayne

    1998-01-01

    Experimental supersonic combustion research related to hypersonic airbreathing propulsion has been actively underway at NASA Langley Research Center (LaRC) since the mid-1960's. This research involved experimental investigations of fuel injection, mixing, and combustion in supersonic flows and numerous tests of scramjet engine flowpaths in LaRC test facilities simulating flight from Mach 4 to 8. Out of this research effort has come scramjet combustor design methodologies, ground test techniques, and data analysis procedures. These technologies have progressed steadily in support of the National Aero-Space Plane (NASP) program and the current Hyper-X flight demonstration program. During NASP nearly 2500 tests of 15 scramjet engine models were conducted in LaRC facilities. In addition, research supporting the engine flowpath design investigated ways to enhance mixing, improve and apply nonintrusive diagnostics, and address facility operation. Tests of scramjet combustor operation at conditions simulating hypersonic flight at Mach numbers up to 17 also have been performed in an expansion tube pulse facility. This paper presents a review of the LaRC experimental supersonic combustion research efforts since the late 1980's, during the NASP program, and into the Hyper-X Program.

  11. Sequential experimental design based generalised ANOVA

    NASA Astrophysics Data System (ADS)

    Chakraborty, Souvik; Chowdhury, Rajib

    2016-07-01

    Over the last decade, surrogate modelling technique has gained wide popularity in the field of uncertainty quantification, optimization, model exploration and sensitivity analysis. This approach relies on experimental design to generate training points and regression/interpolation for generating the surrogate. In this work, it is argued that conventional experimental design may render a surrogate model inefficient. In order to address this issue, this paper presents a novel distribution adaptive sequential experimental design (DA-SED). The proposed DA-SED has been coupled with a variant of generalised analysis of variance (G-ANOVA), developed by representing the component function using the generalised polynomial chaos expansion. Moreover, generalised analytical expressions for calculating the first two statistical moments of the response, which are utilized in predicting the probability of failure, have also been developed. The proposed approach has been utilized in predicting probability of failure of three structural mechanics problems. It is observed that the proposed approach yields accurate and computationally efficient estimate of the failure probability.

  12. Experimental testing of constructivism and related theories.

    PubMed

    Fidelman, U

    1991-10-01

    The purpose of this article is to show that experimental scientific methods can be applied to explain how the analytic mechanism of the left cerebral hemisphere and the synthetic mechanism of the right one create complex cognitive constructions like ontology and mathematics. Nominalism and ordinal mathematical concepts are related to the analytic left hemisphere while Platonism and cardinal mathematical concepts are related to the synthetic right one. Thus persons with a dominant left hemisphere tend to prefer nominalist ontology and have more aptitude for ordinal mathematics than for cardinal mathematics, while persons with a dominant right hemisphere tend to prefer platonist ontology and have more aptitude for cardinal mathematics than for ordinal mathematics. It is further explained how the Kantism temporal mode of perceiving experience can be related to the left hemisphere while the Kantian spatial mode of perceiving experience can be related to the right hemisphere. This relation can be tested experimentally, thus the Kantian source of constructivism, and through it constructivism itself, can be tested experimentally.

  13. Cholestasis: human disease and experimental animal models.

    PubMed

    Rodríguez-Garay, Emilio Alberto

    2003-01-01

    Cholestasis may result from a failure in bile secretion in hepatocytes or ductular cells, or from a blockade to the free bile flow. Human cholestasis may be induced by many drugs, being antibiotics the more common. Other types of cholestasis seen in humans are a group of familial cholestatic disorders, obstructive cholestasis, primary biliary cirrhosis, extrahepatic biliary atresia, primary sclerosing cholangitis, cholestasis of pregnancy, oral contraceptive-induced cholestasis, and sepsis-induced cholestasis. Experimental animal models allow the understanding of pathophysiological mechanisms involved and their clinical correlates. The most common experimental models of intrahepatic cholestasis are estrogen-induced, endotoxin-induced and drug-induced cholestasis. A well known model of extrahepatic biliary obstruction is common bile duct ligation. Drug-induced cholestasis were described using different drugs. On this regard, alpha naphthylisothiocyanate treatment has been extensively used, permitting to describe not only cholestatic alterations but also compensatory mechanisms. Congenital defficiency of transport proteins also were studied in natural rat models of cholestasis. The experimental animal models allow to define down-regulated alterations of hepatocyte transport proteins, and up-regulated ones acting as compensatory mechanisms. In conclusion, animal model and transport protein studies are necessary for the progressive understanding of congenital and acquired human cholestasis, and regulatory mechanisms that operate on liver cells.

  14. Normalization of experimental electron cross sections.

    NASA Astrophysics Data System (ADS)

    Avdonina, N.; Felfli, Z.; Msezane, A. Z.

    1997-10-01

    Absolute experimental electron-impact differential cross sections (DCSs) can be obtained through an extrapolation of the relative generalized oscillator strength (GOS) values at some given impact energy E to zero momentum transfer squared K^2, the optical oscillator strength (OOS) [1]. We propose to normalize the relative experimental DCS data to the corresponding OOS value by extrapolating the GOS to K^2 = 0 without involving the nonphysical region. This is possible only by simultaneously increasing E and decreasing K^2 so that K^2 = 0 corresponds to E = ∞. Thus is avoided a divergence of fracd(GOS)d(K^2) at K^2 = 0 [2]. Another advantage of our method is that, over a wide range of small K^2 values the contribution of higher order terms of the Born series to the GOS function is negligible, contrary to the constant E case in which even order K^2 terms are non-Born [2]. Thus first Born approximation can be used to normalize relative experimental DCSs to the OOS. This method is applicable to both the excitation and ionization of atomic and molecular targets by electron impact. The latter case generalizes the method of ref. [3]. ^*Supported by AFOSR, NSF and DoE Div. of Chemical Sciences, OBES. ^1 E. N. Lassettre et al., J. Chem. Phys \\underline50, (1829) ^2 W. M. Huo, J. Chem. Phys \\underline71, 1593 (1979) ^3 A. Saenz, W Weyrich and P. Froelich, J. Phys. B \\underline29, 97 (1996)

  15. Instrumented tube burns: theoretical and experimental observations

    SciTech Connect

    Yarrington, Cole Davis; Obrey, Stephen J; Foley, Timothy J; Son, Steven F

    2009-01-01

    The advent of widely available nanoscale energetic composites has resulted in a flurry of novel applications. One of these applications is the use of nanomaterials in energetic compositions. In compositions that exhibit high sensitivity to stimulus, these materials are often termed metastable intermolecular composites (MIC). More generally, these compositions are simply called nanoenergetics. Researchers have used many different experimental techniques to analyze the various properties of nanoenergetic systems. Among these various techniques, the confined tube burn is a simple experiment that is capable of obtaining much data related to the combustion of these materials. The purpose of this report is to review the current state of the confined tube burn experiment, including the drawbacks of the technique and possible remedies. As this report is intended to focus on the specific experimental technique, data from many different energetic materials, and experimental configurations will be presented. The qualitative and quantitative data that can be gathered using confined tube burn experiments include burning rates, total impulse, pressure rise rate, and burning rate differences between different detector types. All of these measurements lend insight into the combustion properties and mechanisms of specific nanoenergetics. Finally, certain data indicates a more complicated flow scenario which may need to be considered when developing burn tube models.

  16. Experimental pavement using household waste slag

    SciTech Connect

    Kouda, Masahiro

    1996-12-31

    Municipal wastes used to be simply landfilled, but because of increasing difficulty in finding disposal sites, it became common practice to incinerate wastes and landfill the ash. In view of rapidly dwindling landfill sites, the author thought that the landfill site problem might be solved by finding a way to utilize slag made from incinerator ash. In this paper, a method for utilizing water-granulated slag as an asphalt pavement material is discussed. On the basis of laboratory test results, trial paving using base course materials consisting of crushed stone and 25 or 50% slag was carried out, paying attention primarily to bearing capacity. Marshall tests and fatigue resistance tests were conducted to determine the optimum content of water-granulated slag, and it was concluded that quality comparable to that of conventional asphalt concrete was attained at the slag content of 25% or less and that no problem would arise if the slag content was kept at 60% or less of the fine aggregate content. The mix proportions thus determined were also tested through experimental paving. A follow-up study to evaluate the durability of the experimental pavements confirmed that the experimental pavements were comparable in performance with conventional asphalt concrete pavements. This paper also reports on some problems encountered that need to be solved before utilizing water-granulated slag.

  17. Experimental characterization of the perceptron laser rangefinder

    NASA Technical Reports Server (NTRS)

    Kweon, I. S.; Hoffman, Regis; Krotkov, Eric

    1991-01-01

    In this report, we characterize experimentally a scanning laser rangefinder that employs active sensing to acquire three-dimensional images. We present experimental techniques applicable to a wide variety of laser scanners, and document the results of applying them to a device manufactured by Perceptron. Nominally, the sensor acquires data over a 60 deg x 60 deg field of view in 256 x 256 pixel images at 2 Hz. It digitizes both range and reflectance pixels to 12 bits, providing a maximum range of 40 m and a depth resolution of 1 cm. We present methods and results from experiments to measure geometric parameters including the field of view, angular scanning increments, and minimum sensing distance. We characterize qualitatively problems caused by implementation flaws, including internal reflections and range drift over time, and problems caused by inherent limitations of the rangefinding technology, including sensitivity to ambient light and surface material. We characterize statistically the precision and accuracy of the range measurements. We conclude that the performance of the Perceptron scanner does not compare favorably with the nominal performance, that scanner modifications are required, and that further experimentation must be conducted.

  18. Comparing simulated and experimental molecular cluster distributions.

    PubMed

    Olenius, Tinja; Schobesberger, Siegfried; Kupiainen-Määttä, Oona; Franchin, Alessandro; Junninen, Heikki; Ortega, Ismael K; Kurtén, Theo; Loukonen, Ville; Worsnop, Douglas R; Kulmala, Markku; Vehkamäki, Hanna

    2013-01-01

    Formation of secondary atmospheric aerosol particles starts with gas phase molecules forming small molecular clusters. High-resolution mass spectrometry enables the detection and chemical characterization of electrically charged clusters from the molecular scale upward, whereas the experimental detection of electrically neutral clusters, especially as a chemical composition measurement, down to 1 nm in diameter and beyond still remains challenging. In this work we simulated a set of both electrically neutral and charged small molecular clusters, consisting of sulfuric acid and ammonia molecules, with a dynamic collision and evaporation model. Collision frequencies between the clusters were calculated according to classical kinetics, and evaporation rates were derived from first principles quantum chemical calculations with no fitting parameters. We found a good agreement between the modeled steady-state concentrations of negative cluster ions and experimental results measured with the state-of-the-art Atmospheric Pressure interface Time-Of-Flight mass spectrometer (APi-TOF) in the CLOUD chamber experiments at CERN. The model can be used to interpret experimental results and give information on neutral clusters that cannot be directly measured.

  19. Experimental and analytical study of rotating cavitation

    SciTech Connect

    Kamijo, Kenjiro; Shimura, Takashi; Tsujimoto, Yoshinobu

    1994-12-31

    This paper describes experimental and analytical results of rotating cavitation. There are four major sections in this paper. The first section presents the main characteristics of rotating cavitation which was found in the inducer test using a water tunnel. The second section describes the rotating cavitation which occurred in the development test of an LE-7 liquid oxygen pump for the H-II rocket. Also described in this section is how the rotating cavitation was suppressed. The rotating cavitation was the cause of both super synchronous shaft vibration and an unstable head coefficient curve. The third section presents how the theory of rotating cavitation was developed. The final section shows the measured cavitation compliance and mass flow gain factor of the LE-7 pump inducer for comparison of the experimental and analytical results of the rotating cavitation of the LE-7 pump inducer. Almost all the information presented in this paper has already been reported by Kamijo et al. (1977, 1980, 1993, 1993) and by Shimura (1993). In the present paper, the authors attempt to combine and give a clear overview of the experimental and analytical results described in the previous papers to systematically show their experience and findings on rotating cavitation.

  20. Tectonic strain and paleomagnetism: experimental investigation

    NASA Astrophysics Data System (ADS)

    Borradaile, G.; Mothersill, J.

    1989-09-01

    A porous, clay-rich sandstone with a natural remanent magnetisation shows complex changes in the orientation of the remanence vector when the sandstone is subjected to experimental deformation, at 100 MPa, room temperature and constant natural strain rates of 1 × 10 -5 s -1. The paleomagnetic vector does not simply rotate away from the axis of compression. When the rock is shortened perpendicular to bedding the remanence vector rotates toward the bedding, as expected, but the remanence also rotates toward bedding when the rock is shortened parallel to bedding. Moreover, in some cases the remanence vector changes azimuth within the specimen during experimental deformation. Thus bedding anisotropy and the accompanying mineral-fabric anisotropy are more influential than strain in controlling deflections of the paleomagnetic vector in this study. This anisotropy also influences the post-deformational behaviour of remanence: 4 months after deformation, some cores shortened perpendicular to bedding relaxed their remanence vectors back towards the pre-deformational attitude whereas some other cores continued to show progressive changes. Intragranular, recoverable elastic strains in the magnetic grains may be partly responsible for the experimentally induced deflections of remanence.

  1. The experimental evolution of aging in fruitflies.

    PubMed

    Stearns, S C; Ackermann, M; Doebeli, M

    1998-01-01

    The evolutionary theory of aging suggests that the level of repair will evolve to an intermediate optimum that permits the accumulation of random damage to cells. This, in turn, causes a decline in essential functions during the life span of an organism. The central claim of the life history theory of aging is that intrinsic mortality rates evolve in response to changes in extrinsic mortality rates. To prove this central claim, it must be evaluated experimentally. Experimental evolution is an approach that has been yielding interesting results from both a variety of questions posed and organisms examined. In this article the organism chosen for study is the fruitfly (Drosophilia melanogaster) in which the evolutionary effects of high and low adult mortality rates are compared. It has been found that higher extrinsic mortality rates lead to the evolution of higher intrinsic mortality rates and a shorter life span. This is the first clear experimental demonstration of the central claim of the evolutionary theory of aging.

  2. The rights of man and animal experimentation.

    PubMed

    Martin, J

    1990-09-01

    Since emotions give contradictory signals about animal experimentation in medical science, man's relationship to animals must be based upon reason. Thomas Aquinas argues that man is essentially different from animals because man's intellectual processes show evidence of an abstract mechanism not possessed by animals. Man's rights arise in association with this essential difference. The consequence is that only man possesses true rights by Aquinas's definition; animals have them only by analogy. However, cruelty to animals is illicit and they should be protected, principally not because they have rights, but because he who is cruel to animals is more likely to be cruel to his fellowman. If there is a need for animal experimentation in science for the good of man, this approach gives philosophical justification for experimentation, since man's well-being must come before that of animals because of his unique possession of rights. However, those experiments should be carried out in the kindest way possible, to promote kindness towards man. To see man as solely part of a biological continuum in competition for rights with those beings close to him biologically, detracts from man's dignity.

  3. Physical versus Virtual Manipulative Experimentation in Physics Learning

    ERIC Educational Resources Information Center

    Zacharia, Zacharias C.; Olympiou, Georgios

    2011-01-01

    The aim of this study was to investigate whether physical or virtual manipulative experimentation can differentiate physics learning. There were four experimental conditions, namely Physical Manipulative Experimentation (PME), Virtual Manipulative Experimentation (VME), and two sequential combinations of PME and VME, as well as a control condition…

  4. Experimental and theoretical electronic structure of quinacridone

    NASA Astrophysics Data System (ADS)

    Lüftner, Daniel; Refaely-Abramson, Sivan; Pachler, Michael; Resel, Roland; Ramsey, Michael G.; Kronik, Leeor; Puschnig, Peter

    2014-08-01

    The energy positions of frontier orbitals in organic electronic materials are often studied experimentally by (inverse) photoemission spectroscopy and theoretically within density functional theory. However, standard exchange-correlation functionals often result in too small fundamental gaps, may lead to wrong orbital energy ordering, and do not capture polarization-induced gap renormalization. Here we examine these issues and a strategy for overcoming them by studying the gas phase and bulk electronic structure of the organic molecule quinacridone (5Q), a promising material with many interesting properties for organic devices. Experimentally we perform angle-resolved photoemission spectroscopy (ARUPS) on thin films of the crystalline β phase of 5Q. Theoretically we employ an optimally tuned range-separated hybrid functional (OT-RSH) within density functional theory. For the gas phase molecule, our OT-RSH result for the ionization potential (IP) represents a substantial improvement over the semilocal PBE and the PBE0 hybrid functional results, producing an IP in quantitative agreement with experiment. For the bulk crystal we take into account the correct screening in the bulk, using the recently developed optimally tuned screened range-separated hybrid (OT-SRSH) approach, while retaining the optimally tuned parameters for the range separation and the short-range Fock exchange. This leads to a band gap narrowing due to polarization effects and results in a valence band spectrum in excellent agreement with experimental ARUPS data, with respect to both peak positions and heights. Finally, full-frequency G0W0 results based on a hybrid functional starting point are shown to agree with the OT-SRSH approach, improving substantially on the PBE-starting point.

  5. Initial Experimental Airworthiness Certification Guidance for UAS. UAS Experimental Certification Process and Guidance

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This paper addresses the regulatory processes and requirements already in place by which an applicant might obtain experimental airworthiness certification for a civil Unmanned Aircraft System (UAS). It is more extensive and subsequent to an earlier, similar deliverable, PD007, which was an interim study of the same topic. Since few regulatory airworthiness and operating standards exist for UAS like those for traditional manned aircraft and since most UAS have historically been developed and operated under military auspices, civil use of UAS in the NAS is a new and unfamiliar challenge requiring specific and unique considerations. Experimental certification is the most basic level of FAA approval toward routine UAS operation in the NAS. The paper reviews and explains existing FAA requirements for an applicant seeking experimental airworthiness approval and details the process for submission of necessary information. It summarizes the limited purposes for which experimental aircraft may be used and addresses pertinent aspects of UAS design, construction and operation in the NAS in harmony with traditional manned aircraft. Policy IPT position is that UAS, while different from manned aircraft, can use the same initial processes to gain civil operating experience under the experimental approval. Particular note is taken of those UAS-unique characteristics which require extra attention to assure equivalent safety of operation, such as the UAS control station and sense-and-avoid. The paper also provides "best practices" guidance for UAS manufacturers and FAA personnel in two appendices. The material in Appendix A is intended to provide guidance on assuring UAS safety to FAA, and provides FAA personnel with a suggested list of items to review, with a focus on UAS unique factors, prior to issuance of an experimental airworthiness certificate. Appendix B provides an outline for a program letter which a manufacturer could use in preparing the application for an UAS

  6. Systemic lupus erythematosus: Clinical and experimental aspects

    SciTech Connect

    Smolen, J.S.

    1987-01-01

    This text covers questions related to the history, etiology, pathogenesis, clinical aspects and therapy of systematic lupus erythematosus (SLE). Both animal models and human SLE are considered. With regard to basic science, concise information on cellular immunology, autoantibodies, viral aspects and molecular biology in SLE is provided. Clinical topics then deal with medical, dermatologic, neurologic, radiologic, pathologic, and therapeutic aspects. The book not only presents the most recent information on clinical and experimental insights, but also looks at future aspects related to the diagnosis and therapy of SLE.

  7. Extensive experimental mapping of sonoluminescence parameter space

    PubMed

    Ketterling; Apfel

    2000-04-01

    Experimental phase diagrams are compared to theoretical predictions based on the Dissociation Hypothesis (DH) theory of single bubble sonoluminescence (SBSL). Ambient radius (R(o))- acoustic drive pressure (P(a)) phase diagrams are presented for krypton-nitrogen mixtures and for a collection of data with other noble gas-nitrogen mixtures. The data is also presented in terms of expansion ratio (maximum bubble radius R(max)/R(o)) vs P(a) and relative light intensity vs P(a). The results provide further evidence of the validity of DH and also provide a thorough mapping of SBSL at a single frequency.

  8. Scaling Vegetation on Experimental Channel Patterns

    NASA Astrophysics Data System (ADS)

    van Breemen, D. M.; van de Lageweg, W. I.; van Dijk, W. M.; Kleinhans, M. G.

    2010-12-01

    There are strong feedbacks between river channels, floodplains and riparian and floodplain vegetation. We study the effect of experimental vegetation on channel pattern. Through linear bar theory it is known that channel width-depth ratio affects bar pattern and relatively narrow channels with strong banks are required for meandering. Riparian vegetation is able to alter the channel width-depth ratio and therefore the channel pattern through strengthening of the banks. Floodplain vegetation adds hydraulic resistance so the flow is more focused into the channels. However, determination of the underlying mechanisms and processes has remained scarce and qualitative and hence these effects are not yet fully understood. The objectives of this study are 1) to develop a controllable and scalable method to reproduce vegetation effect in experimental self-formed channels, and 2) to experimentally determine the effects of riparian vegetation on bank strength, channel pattern and meandering dynamics. Sprouts of three plant species were systematically subjected to different seeding densities and to various growing conditions, including light intensity, submergence and nutrient starvation. Denser seeding reduced sprout growth after about a week. Stronger light increased plant growth and plant strength. Nutrient starvation caused different branching intensity of the root system. Tens of small-scale bank erosion experiments and bank failure experiments (see Kleinhans et al., this conference) were performed to quantify the strength of banks reinforced by plant roots at the experimental scale, demonstrating that bank strength is strongly determined by seeding density, rooting density and depth relative to channel depth. To study pattern evolution and morphodynamics we used a 1.25x7.5 m flume with a constant discharge and sediment feed. The introduction of vegetation in experiments results in narrower and deeper channels. Higher vegetation density leads to static channels with

  9. Experimental investigations of the ozone zero phenomenon

    NASA Astrophysics Data System (ADS)

    Murayama, K.; Matsumura, N.; Taguchi, M.; Katoh, Y.; Teranishi, K.; Suzuki, S.; Itoh, H.

    2009-08-01

    An experimental study is carried out to clarify the mechanism of the ozone zero phenomenon. Temporal variations of both the discharge characteristics and the metallic electrode surface in the ozone generator are investigated by the Lissajous figure method and Auger electron spectroscopy (AES), respectively. The AES results suggest that a number of oxygen atoms penetrate into the stainless-steel electrode owing to the exposure to ozone. Such a surface change would result in the temporal variation of the discharge characteristics of the generator.

  10. Fixed Target Beauty Physics Experimental Programs

    SciTech Connect

    Garbincius, P.H.

    1987-11-01

    The current and near term future fixed target physics efforts in observing particles with open beauty are reviewed. This includes a compilation of the non-observation upper limits and the observation of both upsilon and b-states. A short discussion of the theoretical predictions for the hadro-produced beauty pairs is included. The major part of this review is devoted to the techniques and tricks employed, a survey of the current and proposed experiments. A personal summary of the experimental prospects concludes this report. 28 refs., 26 figs.

  11. Experimental Demonstration of a Tunable Microwave Undulator

    NASA Astrophysics Data System (ADS)

    Tantawi, Sami; Shumail, Muhammad; Neilson, Jeffery; Bowden, Gordon; Chang, Chao; Hemsing, Erik; Dunning, Michael

    2014-04-01

    Static magnetic undulators used by x-ray light sources are fundamentally too limited to achieve shorter undulator periods and dynamic control. To overcome these limitations, we report experimental demonstration of a novel short-period microwave undulator, essentially a Thomson scattering device, that has yielded tunable spontaneous emission and seeded coherent radiation. Its equivalent undulator period (λu) is 13.9 mm while it has achieved an equivalent magnetic field of 0.65 T. For future-generation light sources, this device promises a shorter undulator period, a large aperture, and fast dynamic control.

  12. Modernization of experimental air turbine VT-400

    NASA Astrophysics Data System (ADS)

    Klimko, Marek; Okresa, Daniel

    2016-06-01

    This article briefly describes a modernization of the experimental device - air turbine (VT-400), which is a part of the research activities at the Department of Power System Engineering, University of West Bohemia (KKE-UWB). This device serves for the research of steam turbine blades within the framework of a long-term cooperation between the Department and Doosan Skoda Power (DSPW). Due to the age of the device, some necessary changes had to be performed and some obsolete components had to be replaced or new ones added. A part of this article is also a comparison with the previous state and an evaluation of the contribution after the reconstruction.

  13. [Experimental models of human skin aging].

    PubMed

    Nikolakis, G; Zoschke, C; Makrantonaki, E; Hausmann, C; Schäfer-Korting, M; Zouboulis, C C

    2016-02-01

    The skin is a representative model for the study of human aging. Despite the high regenerative capacity of the skin, skin physiology changes over the course of life. Medical and cosmetic research is trying to prevent aging, to slow, to stop, or to reverse it. Effects of age-related DNA damage and of changing skin structure on pharmacological parameters are largely unknown. This review article summarizes the state of scientific knowledge in the field of experimental models of human skin aging and shows approaches to improve organotypic skin models, to develop predictive models of aging, and improve aging research.

  14. Experimental demonstration of superdirective dielectric antenna

    SciTech Connect

    Krasnok, Alexander E.; Filonov, Dmitry S.; Belov, Pavel A.; Simovski, Constantin R.; Kivshar, Yuri S.

    2014-03-31

    We propose and demonstrate experimentally a simple approach for achieving superdirectivity of emitted radiation for electrically small antennas based on a spherical dielectric resonator with a notch excited by a dipole source. Superdirectivity is achieved without using complex antenna arrays and for a wide range of frequencies. We also demonstrate the steering effect for a subwavelength displacement of the source. Finally, unlike previously known superdirective antennas, our design has significantly smaller losses, at the operation frequency radiation efficiency attains 80%, and matching holds in the 3%-wide frequency band without any special matching technique.

  15. Experimental needs of high temperature concrete

    SciTech Connect

    Chern, J.C.; Marchertas, A.H.

    1985-01-01

    The needs of experimental data on concrete structures under high temperature, ranging up to about 370/sup 0/C for operating reactor conditions and to about 900/sup 0/C and beyond for hypothetical accident conditions, are described. This information is required to supplement analytical methods which are being implemented into the finite element code TEMP-STRESS to treat reinforced concrete structures. Recommended research ranges from material properties of reinforced/prestressed concrete, direct testing of analytical models used in the computer codes, to investigations of certain aspects of concrete behavior, the phenomenology of which is not well understood. 10 refs.

  16. Calorimetric thermobarometry of experimentally shocked quartz

    NASA Technical Reports Server (NTRS)

    Ocker, Katherine D.; Gooding, James L.; Hoerz, Friedrich

    1994-01-01

    Structural damage in experimentally shock-metamorphosed, granular quartz is quantitatively measurable by differential scanning calorimetry (DSC). Shock-induced loss of crystallinity is witnessed by disappearance of the alpha/beta phase transformation and evolution of a broad endoenthalpic strain peak at 650-900 K. The strain-energy peak grows rapidly at less than 10 GPa but declines with increasing shock pressure; it approaches zero at 32 GPa where vitrification is extensive. Effects of grain size and post-shock thermal history must be better understood before calorimetric thermobarometry of naturally shocked samples becomes possible.

  17. Experimental realization of chaos control by thresholding.

    PubMed

    Murali, K; Sinha, Sudeshna

    2003-07-01

    We report the experimental verification of thresholding as a versatile tool for efficient and flexible chaos control. The strategy here simply involves monitoring a single state variable and resetting it when it exceeds a threshold. We demonstrate the success of the technique in rapidly controlling different chaotic electrical circuits, including a hyperchaotic circuit, onto stable fixed points and limit cycles of different periods, by thresholding just one variable. The simplicity of this controller entailing no run-time computation, and the ease and rapidity of switching between different targets it offers, suggests a potent tool for chaos based applications.

  18. Experimental investigation of a solar bamboo dryer

    SciTech Connect

    Ong, K.S.

    1996-05-01

    An experimental investigation was conducted on the performance of a solar box dryer for drying bamboo operating under tropical weather conditions. The dryer is a greenhouse-type designed for multi-crop solar drying. Air circulation was by electrically-operated fan. The results showed that the moisture content of the bamboo could be brought down to about 19% from an initial value of nearly 90% in 17 days by operating the dryer over 8 hours each day. Under natural drying conditions, the final moisture content reached was only 22%. Although solar drying of bamboo was only marginally faster than natural drying, nonetheless, final moisture content was lower.

  19. Experimental Study of Nucleon Structure and QCD

    SciTech Connect

    Jian-Ping Chen

    2012-03-01

    Overview of Experimental Study of Nucleon Structure and QCD, with focus on the spin structure. Nucleon (spin) Structure provides valuable information on QCD dynamics. A decade of experiments from JLab yields these exciting results: (1) valence spin structure, duality; (2) spin sum rules and polarizabilities; (3) precision measurements of g{sub 2} - high-twist; and (4) first neutron transverse spin results - Collins/Sivers/A{sub LT}. There is a bright future as the 12 GeV Upgrade will greatly enhance our capability: (1) Precision determination of the valence quark spin structure flavor separation; and (2) Precision extraction of transversity/tensor charge/TMDs.

  20. Modelling Experimental Procedures for Manipulator Calibration

    DTIC Science & Technology

    1991-12-01

    AD-A245 603 NAVAL POSTGRADUATE SCHOOL Monterey, California RA D TIC THESIS F-a 1 . MODELLING EXPERIMENTAL PROCEDURES FOR MANIPULATOR CALIBRATION by...William E. Swayze December 1991 Thesis Advisor: Morris R. Driels Approved for public release; distribution is unlimited 92-03143 Uncl ass if ied...2 PERSONAL AUTHORS WILLI.TM E. SWAYZE 13a TYPE OF REPORT 13o TIME COVERED 14. DATE OF REPORT (Year, Mon.th Day) 15 PAGE COUNT Master’s Thesis FROM

  1. Experimental comparison of exchange bias measurement methodologies

    SciTech Connect

    Hovorka, Ondrej; Berger, Andreas; Friedman, Gary

    2007-05-01

    Measurements performed on all-ferromagnetic bilayer systems and supported by model calculation results are used to compare different exchange bias characterization methods. We demonstrate that the accuracy of the conventional two-point technique based on measuring the sum of the coercive fields depends on the symmetry properties of hysteresis loops. On the other hand, the recently proposed center of mass method yields results independent of the hysteresis loop type and coincides with the two-point measurement only if the loops are symmetric. Our experimental and simulation results clearly demonstrate a strong correlation between loop asymmetry and the difference between these methods.

  2. Experimental Study of Dust Grain Charging

    NASA Technical Reports Server (NTRS)

    Spann, James F; Venturini, Catherine C.; Comfort, Richard H.; Mian, Abbas M.

    1999-01-01

    The results of an experimental study of the charging mechanisms of micron size dust grains are presented. Individual dust grains are electrodynamically suspended and exposed to an electron beam of known energy and flux, and to far ultraviolet radiation of known wavelength and intensity. Changes in the charge-to-mass ratio of the grain are directly measured as a function of incident beam (electron and/or photon), grain size and composition. Comparisons of our results to theoretical models that predict the grain response are presented.

  3. Irradiation Design for an Experimental Murine Model

    SciTech Connect

    Ballesteros-Zebadua, P.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Celis, M. A.; Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A.; Rubio-Osornio, M. C.; Custodio-Ramirez, V.; Paz, C.

    2010-12-07

    In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

  4. Human Factors Experimental Design and Analysis Reference

    DTIC Science & Technology

    2007-07-01

    and R2Adj – PRESS Statistic – Mallows C(p) A linear regression model that includes all predictors investigated may not be the best model in terms of...as the Adjusted Coefficient of Determination, R2Adj, the PRESS statistic, and Mallows C(p) value. Human Factors Experimental Design and Analysis...equations with highest R2 using R2Adj, PRESS, and Mallows C(p) • Evaluation – Cumbersome as number of X’s increase 10 X’s = (210-1) = 1,023 Regression

  5. Irradiation Design for an Experimental Murine Model

    NASA Astrophysics Data System (ADS)

    Ballesteros-Zebadúa, P.; Lárraga-Gutierrez, J. M.; García-Garduño, O. A.; Rubio-Osornio, M. C.; Custodio-Ramírez, V.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Paz, C.; Celis, M. A.

    2010-12-01

    In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

  6. Experimental quantum private queries with linear optics

    SciTech Connect

    De Martini, Francesco; Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Nagali, Eleonora; Sansoni, Linda; Sciarrino, Fabio

    2009-07-15

    The quantum private query is a quantum cryptographic protocol to recover information from a database, preserving both user and data privacy: the user can test whether someone has retained information on which query was asked and the database provider can test the amount of information released. Here we discuss a variant of the quantum private query algorithm that admits a simple linear optical implementation: it employs the photon's momentum (or time slot) as address qubits and its polarization as bus qubit. A proof-of-principle experimental realization is implemented.

  7. Experimental Techniques for Thermodynamic Measurements of Ceramics

    NASA Technical Reports Server (NTRS)

    Jacobson, Nathan S.; Putnam, Robert L.; Navrotsky, Alexandra

    1999-01-01

    Experimental techniques for thermodynamic measurements on ceramic materials are reviewed. For total molar quantities, calorimetry is used. Total enthalpies are determined with combustion calorimetry or solution calorimetry. Heat capacities and entropies are determined with drop calorimetry, differential thermal methods, and adiabatic calorimetry . Three major techniques for determining partial molar quantities are discussed. These are gas equilibration techniques, Knudsen cell methods, and electrochemical techniques. Throughout this report, issues unique to ceramics are emphasized. Ceramic materials encompass a wide range of stabilities and this must be considered. In general data at high temperatures is required and the need for inert container materials presents a particular challenge.

  8. Theoretical and Experimental Beam Plasma Physics (TEBPP)

    NASA Technical Reports Server (NTRS)

    Roberts, B.

    1986-01-01

    The theoretical and experimental beam plasma physics (TEBPP) consists of a package of five instruments to measure electric and magnetic fields, plasma density and temperature, neutral density, photometric emissions, and energetic particle spectra during firings of the particle injector (SEPAC) electron beam. The package is developed on a maneuverable boom (or RMS) and is used to measure beam characteristics and induced perturbations field ( 10 m) and mid field ( 10 m to 100 m) along the electron beam. The TEBPP package will be designed to investigate induced oscillations and induced electromagnetic mode waves, neutral and ion density and temperature effects, and beam characteristics as a function of axial distance.

  9. Theoretical and Experimental Beam Plasma Physics (TEBPP)

    NASA Technical Reports Server (NTRS)

    Roberts, W. T.

    1985-01-01

    The theoretical and experimental beam plasma physics (TEBPP) consists of a package of five instruments to measure electric and magnetic fields, plasma density and temperature, neutral density, photometric emissions, and energetic particle spectra during firings of the particle injector (SEPAC) electron beam. The package is deployed on a maneuverable boom (or RMS) and is used to measure beam characteristics and induced perturbations in the near field ( 10 m) and mid field (10 m to 100 m) along the electron beam. The TEBPP package will be designed to investigate induced oscillations and induced electromagnetic mode waves, neutral and ion density and temperature effects, and beam characteristics as a function of axial distance.

  10. GAS CURTAIN EXPERIMENTAL TECHNIQUE AND ANALYSIS METHODOLOGIES

    SciTech Connect

    J. R. KAMM; ET AL

    2001-01-01

    The qualitative and quantitative relationship of numerical simulation to the physical phenomena being modeled is of paramount importance in computational physics. If the phenomena are dominated by irregular (i. e., nonsmooth or disordered) behavior, then pointwise comparisons cannot be made and statistical measures are required. The problem we consider is the gas curtain Richtmyer-Meshkov (RM) instability experiments of Rightley et al. (13), which exhibit complicated, disordered motion. We examine four spectral analysis methods for quantifying the experimental data and computed results: Fourier analysis, structure functions, fractal analysis, and continuous wavelet transforms. We investigate the applicability of these methods for quantifying the details of fluid mixing.

  11. GAS CURTAIN EXPERIMENTAL TECHNIQUE AND ANALYSIS METHODOLOGIES.

    SciTech Connect

    Kamm, J. R.; Rider, William; Rightley, P. M.; Prestridge, K. P.; Benjamin, R. F.; Vorobieff, P. V.

    2001-01-01

    The qualitative and quantitative relationship of numerical simulation to the physical phenomena being modeled is of paramount importance in computational physics. If the phenomena are dominated by irregular (i.e., nonsmooth or disordered) behavior, then pointwise comparisons cannot be made and statistical measures are required. The problem we consider is the gas curtain Richtmyer-Meshkov (RM) instability experiments of Rightley et al. [13], which exhibit complicated, disordered motion. We examine four spectral analysis methods for quantifying the experimental data and computed results: Fourier analysis, structure functions, fractal analysis, and continuous wavelet transforms. We investigate the applicability of these methods for quantifying the details of fluid mixing.

  12. Anisotropic elasticity of experimental colloidal Wigner crystals.

    PubMed

    Russell, Emily R; Spaepen, Frans; Weitz, David A

    2015-03-01

    Colloidal particles interacting via a long-range repulsion can, in contrast to hard-sphere systems, exhibit crystalline ordering at low volume fraction. Here we experimentally investigate the structure and properties of such "colloidal Wigner crystals." We find a body-centered-cubic crystalline phase at volume fractions of ϕ≳15%, which exhibits large fluctuations of individual particles from their average positions. We determine the three independent crystalline elastic constants and find that these crystals are very compliant and highly anisotropic.

  13. [Experimental and theoretical high energy physics program

    SciTech Connect

    Finley, J.; Gaidos, J.A.; Loeffler, F.J.; McIlwain, R.L.; Miller, D.H.; Palfrey, T.R.; Shibata, E.I.; Shipsey, I.P.

    1993-04-01

    Experimental and theoretical high-energy physics research at Purdue is summarized in a number of reports. Subjects treated include the following: the CLEO experiment for the study of heavy flavor physics; gas microstrip detectors; particle astrophysics; affine Kac{endash}Moody algebra; nonperturbative mass bounds on scalar and fermion systems due to triviality and vacuum stability constraints; resonance neutrino oscillations; e{sup +}e{sup {minus}} collisions at CERN; {bar p}{endash}p collisions at FNAL; accelerator physics at Fermilab; development work for the SDC detector at SSC; TOPAZ; D-zero physics; physics beyond the standard model; and the Collider Detector at Fermilab. (RWR)

  14. Experimental confirmation of neoclassical Compton scattering theory

    SciTech Connect

    Aristov, V. V.; Yakunin, S. N.; Despotuli, A. A.

    2013-12-15

    Incoherent X-ray scattering spectra of diamond and silicon crystals recorded on the BESSY-2 electron storage ring have been analyzed. All spectral features are described well in terms of the neoclassical scattering theory without consideration for the hypotheses accepted in quantum electrodynamics. It is noted that the accepted tabular data on the intensity ratio between the Compton and Rayleigh spectral components may significantly differ from the experimental values. It is concluded that the development of the general theory (considering coherent scattering, incoherent scattering, and Bragg diffraction) must be continued.

  15. Clara Maass, yellow fever and human experimentation.

    PubMed

    Chaves-Carballo, Enrique

    2013-05-01

    Clara Louise Maass, a 25-year-old American nurse, died of yellow fever on August 24, 1901, following experimental inoculation by infected mosquitoes in Havana, Cuba. The human yellow fever experiments were initially conducted by MAJ Walter Reed, who first used written informed consent and proved the validity of Finlay's mosquito-vector hypothesis. Despite informed consent form and an incentive of $100 in U.S. gold, human subjects were exposed to a deadly virus. The deaths of Clara Maass and two Spanish immigrants resulted in a public outcry and the immediate cessation of yellow fever human experiments in Cuba.

  16. Dark matter: Observational manifestation and experimental searches

    NASA Astrophysics Data System (ADS)

    Vavilova, I. B.; Bolotin, Yu. L.; Boyarsky, A. M.; Danevich, F. A.; Kobychev, V. V.; Tretyak, V. I.; Babyk, Iu. V.; Iakubovskyi, D. A.; Hnatyk, B. I.; Sergeev, S. G

    2015-08-01

    This monograph is the third issue of a three volume edition under the general title "Dark Energy and Dark Matter in the Universe". The authors discuss the astrophysical direct and indirect manifestation and properties of dark matter in galaxies, galaxy clusters and groups; the different mechanisms of energy exchange between dark energy and dark matter that expand the capabilities of the Standard Cosmological Model; the experimental search for dark matter particle candidates (including the sterile neutrinos, solar axions,weakly-interacting massive particles, and superheavy dark matter particles) using space, ground-based, and underground observatories.

  17. LAPR: An experimental aircraft pushbroom scanner

    NASA Technical Reports Server (NTRS)

    Wharton, S. W.; Irons, J. I.; Heugel, F.

    1980-01-01

    A three band Linear Array Pushbroom Radiometer (LAPR) was built and flown on an experimental basis by NASA at the Goddard Space Flight Center. The functional characteristics of the instrument and the methods used to preprocess the data, including radiometric correction, are described. The radiometric sensitivity of the instrument was tested and compared to that of the Thematic Mapper and the Multispectral Scanner. The radiometric correction procedure was evaluated quantitatively, using laboratory testing, and qualitatively, via visual examination of the LAPR test flight imagery. Although effective radiometric correction could not yet be demonstrated via laboratory testing, radiometric distortion did not preclude the visual interpretation or parallel piped classification of the test imagery.

  18. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect

    Lee C. Cadwallader

    2004-09-01

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air, and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard assoicated with compressed gas cylinders and mthods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  19. The experimental investigation of supersymmetry breaking

    SciTech Connect

    Peskin, M.E.

    1996-04-01

    If Nature is supersymmetric at the weak interaction scale, what can we hope to learn from experiments on supersymmetric particles? The most mysterious aspect of phenomenological supersymmetry is the mechanism of spontaneous supersymmetry breaking. This mechanism ties the observable pattern of supersymmetric particle masses to aspects of the underlying unified theory at very small distance scales. In this article, I will discuss a systematic experimental program to determine the mechanism of supersymmetry breaking. Both pp and e{sup +}e{sup -} colliders of the next generation play an essential role.

  20. Experimenter's Laboratory for Visualized Interactive Science

    NASA Technical Reports Server (NTRS)

    Hansen, Elaine R.; Rodier, Daniel R.; Klemp, Marjorie K.

    1994-01-01

    ELVIS (Experimenter's Laboratory for Visualized Interactive Science) is an interactive visualization environment that enables scientists, students, and educators to visualize and analyze large, complex, and diverse sets of scientific data. It accomplishes this by presenting the data sets as 2-D, 3-D, color, stereo, and graphic images with movable and multiple light sources combined with displays of solid-surface, contours, wire-frame, and transparency. By simultaneously rendering diverse data sets acquired from multiple sources, formats, and resolutions and by interacting with the data through an intuitive, direct-manipulation interface, ELVIS provides an interactive and responsive environment for exploratory data analysis.

  1. Tests of strain analysis by experimental deformation

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; McArthur, J.

    1991-01-01

    The linearisation method and Robin's method of strain analysis of granular materials yield accurate strain estimates for a variety of materials deformed experimentally in pure shear. The breakdown of continuum behaviour at high pore fluid pressures causes the methods to overestimate the strain because they do not take added rigid-body rotation into account. Both methods tolerate some variation in initial shape ratio and some degree of initial preferred orientation at modest strains. Results of tests on polymict sandstone indicate that the lower than average ductility of competent clasts may be balanced against an unfavourable degree of preferred orientation to yield an improved strain estimate.

  2. Experimental strategies towards treating mitochondrial DNA disorders.

    PubMed

    Gardner, Julie L; Craven, Lyndsey; Turnbull, Douglass M; Taylor, Robert W

    2007-06-01

    An extensive range of molecular defects have been identified in the human mitochondrial genome (mtDNA), causing a range of clinical phenotypes characterized by mitochondrial respiratory chain dysfunction. Sadly, given the complexities of mitochondrial genetics, there are no available cures for mtDNA disorders. In this review, we consider experimental, genetic-based strategies that have been or are being explored towards developing treatments, focussing on two specific areas which we are actively pursuing--assessing the benefit of exercise training for patients with mtDNA defects, and the prevention of mtDNA disease transmission.

  3. Experimental single qubit quantum secret sharing.

    PubMed

    Schmid, Christian; Trojek, Pavel; Bourennane, Mohamed; Kurtsiefer, Christian; Zukowski, Marek; Weinfurter, Harald

    2005-12-02

    We present a simple and practical protocol for the solution of a secure multiparty communication task, the secret sharing, and its proof-of-principle experimental realization. In this protocol, a secret is split among several parties in a way that its reconstruction requires the collaboration of the participating parties. In our scheme the parties solve the problem by sequential transformations on a single qubit. In contrast with recently proposed schemes involving multiparticle Greenberger-Horne-Zeilinger states, the approach demonstrated here is much easier to realize and scalable in practical applications.

  4. Pellet impact drilling operational parameters: experimental research

    NASA Astrophysics Data System (ADS)

    Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Aliev, F. R.; Gorbenko, M. V.; Baranova, A. V.

    2015-02-01

    The article deals with the study of particle-impact drilling that is designed to enhance the rate-of-penetration function in hard and tough drilling environments. It contains the experimental results on relation between drilling parameters and drilling efficiency, the experiments being conducted by means of a specially designed laboratory model. To interpret the results properly a high-speed camera was used to capture the pellet motion. These results can be used to choose optimal parameters, as well as to develop enhanced design of ejector pellet impact drill bits.

  5. Upper level experimental physics resource materials

    NASA Astrophysics Data System (ADS)

    Larson, Lee E.

    1992-04-01

    During a 1990 NSF-sponsored workshop on improving upper level experimental physics laboratories, it was agreed that a list of resources from publishers and from institutions with strong upper level labs would be useful to the physics teaching community. This compilation is by no means exhaustive, and suggestions for additions are welcome. If you have or know of materials that should be included, please contact the compiler of this list, Lee Larson, Department of Physics, Denison University, Granville, Ohio (614-587-6468; Bitnet LARSON@DENISON).

  6. Experimental verification of a large flexible manipulator

    NASA Technical Reports Server (NTRS)

    Lee, Jac Won; Huggins, James D.; Book, Wayne J.

    1988-01-01

    A large experimental lightweight manipulator would be useful for material handling, for welding, or for ultrasonic inspection of a large structure, such as an airframe. The flexible parallel link mechanism is designed for high rigidity without increasing weight. This constrained system is analyzed by singular value decomposition of the constraint Jacobian matrix. A verification of the modeling using the assumed mode method is presented. Eigenvalues and eigenvectors of the linearized model are compared to the measured system natural frequencies and their associated mode shapes. The modeling results for large motions are compared to the time response data from the experiments. The hydraulic actuator is verified.

  7. Theoretical and experimental studies on the foundation theoretical and experimental studies on the foundation of mesomechanics

    NASA Astrophysics Data System (ADS)

    Chudnovsky, A.; Wu, S.

    1992-06-01

    The report summarizes a closely coupled experimental and theoretical investigation of various stages of Fracture Process: (1) accumulation of 'damage' on submicroscopical and microscopical scales leading to crack initiation; (2) slow (subcritical) crack growth and an evolution of the damage zone; (3) transition to dynamic crack growth and the catastrophic failure. The experimental part of the program is focused on the observation and quantitative characterization of damage preceding and accompanying crack initiation and growth. A special experimental setup for studying the fracture process under variable stress field is reported in Chapter 2. A leading role of crack-damage interaction in fracture process is well documented. A new formalism for solution of crack-microcrack array interaction problem and its successful implementation in the evaluation of crack layer driving forces is presented in Chapter 3. A new model of the process zone, which generalizes the well-known Dagdale-Barenblatt model is presented in Chapter 4. A new measure for material toughness and the prediction of R-curve behavior illustrate the practical application of our model. Experimental examinations of our model under various test conditions are reported in Chapters 4, 5 and 6. The development of the constitutive equations for Crack Layer evolution and their experimental examinations under stress relaxation, fatigue and creep conditions are reported in Chapters 5 and 6. An accelerated test procedure and the formulation of crack layer instability criteria as a substitution for the conventional fracture toughness parameters are also discussed in Chapter 6.

  8. An Experimental Study of Soft Lubrication

    NASA Astrophysics Data System (ADS)

    Wu, Qianhong; Gacka, Thomas; Nathan, Rungun; Wu, Li-Zhu; Cbmss Team

    2012-11-01

    Lift generation in soft porous media, as a planing surface glides over it, is a new topic in porous media flow with superior potential for lubrication and squeeze damping. This paper presents the first experimental study of this phenomenon. The experimental setup consists of a running conveyer belt covered with a soft porous sheet, and a stationary instrumented inclined planar upper board. Twelve pressure transducers mounted on the upper board captured the pore pressure generation, while a load cell was used to capture the total lifting force, arising from both the pore pressure and the compression of the solid fibers. One finds that the pore pressure distribution is consistent with theoretical predictions (Feng and Weinbaum, JFM, 2000; Wu et al., MSSE, 2006, 2011), and depends on the running belt velocity, U, the mechanical properties of the porous material, and the compression ratios of the porous layer. For a typical trial (h2/h1=5,h2/h0=1, U=3.8 m/s, where h2, h1, and h0 are the leading edge, trailing edge, and undeformed porous layer thicknesses, respectively), 68% of the lifting force was generated by the pore pressure. It conclusively demonstrates the validity of using soft porous materials for super lubrication. applications. Villanova Cellular Biomechanics and Sports Science Laboratory.

  9. Experimental verification of dynamic soaring in albatrosses.

    PubMed

    Sachs, G; Traugott, J; Nesterova, A P; Bonadonna, F

    2013-11-15

    Dynamic soaring is a small-scale flight manoeuvre which is the basis for the extreme flight performance of albatrosses and other large seabirds to travel huge distances in sustained non-flapping flight. As experimental data with sufficient resolution of these small-scale movements are not available, knowledge is lacking about dynamic soaring and the physical mechanism of the energy gain of the bird from the wind. With new in-house developments of GPS logging units for recording raw phase observations and of a dedicated mathematical method for postprocessing these measurements, it was possible to determine the small-scale flight manoeuvre with the required high precision. Experimental results from tracking 16 wandering albatrosses (Diomedea exulans) in the southern Indian Ocean show the characteristic pattern of dynamic soaring. This pattern consists of four flight phases comprising a windward climb, an upper curve, a leeward descent and a lower curve, which are continually repeated. It is shown that the primary energy gain from the shear wind is attained in the upper curve where the bird changes the flight direction from windward to leeward. As a result, the upper curve is the characteristic flight phase of dynamic soaring for achieving the energy gain necessary for sustained non-flapping flight.

  10. Wright's shifting balance theory: an experimental study.

    PubMed

    Wade, M J; Goodnight, C J

    1991-08-30

    Experimental confirmation of Wright's shifting balance theory of evolution, one of the most comprehensive theories of adaptive evolution, is presented. The theory is regarded by many as a cornerstone of modern evolutionary thought, but there has been little direct empirical evidence supporting it. Some of its underlying assumptions are viewed as contradictory, and the existence and efficacy of the theory's fundamental adaptive process, interdemic selection, is the focus of controversy. Interdemic selection was imposed on large arrays of laboratory populations of the flour beetle Tribolium castaneum in the manner described by Wright: the differential dispersion of individuals from demes of high fitness into demes of low fitness. A significant increase in average fitness was observed in the experimental arrays when compared to control populations with equivalent but random migration rates. The response was not proportional to the selection differential: The largest response occurred with interdemic selection every two generations rather than every generation or every three generations. The results indicate that the interdemic phase of Wright's shifting balance theory can increase average fitness and suggest that gene interactions are involved in the observed response.

  11. Feasibility study of the AOSTA experimental campaign

    NASA Astrophysics Data System (ADS)

    Carta, M.; Blaise, P.; Bethaz, C.; Boccia, F.; Fabrizio, V.; Geslot, B.; Grossi, A.; Gruel, A.

    2016-03-01

    The reduction of the nuclear waste is one of the most important nuclear issues. The high radiotoxicity of the spent fuel is due to plutonium and some minor actinides (MAs) such as neptunium, americium and curium, above all. One way to reduce their hazard is to destroy by fission MAs in appropriate nuclear reactors. To allow the MAs destruction an important effort have been done on the nuclear data due to the poor knowledge in this field. In the framework of one of the NEA Expert Group on Integral Experiments for Minor Actinide Management an analysis of the feasibility of MAs irradiation campaign in the TAPIRO fast research reactor is carried out. This paper provides preliminary results obtained by calculations modelling the irradiation, in different TAPIRO irradiation channels, of some CEA samples coming from the French experimental campaign OSMOSE, loaded with different contents of MAs, in order to access, through particular peak spectrometry, to their capture cross section. On the basis of neutron transport calculation results, obtained by both deterministic and Monte Carlo methods, an estimate of the irradiated samples counting levels from the AOSTA (Activation of OSMOSE Samples in TAPIRO) experimental campaign is provided.

  12. L-arginine-induced experimental pancreatitis

    PubMed Central

    Hegyi, Péter; Jr, Zoltán Rakonczay; Sári, Réka; Góg, Csaba; Lonovics, János; Takács, Tamás; Czakó, László

    2004-01-01

    Despite medical treatment, the lethality of severe acute pancreatitis is still high (20%-30%). Therefore, it is very important to find good animal models to characterise the events of this severe disease. In 1984, Mizunuma et al[1] developed a new type of experimental necrotizing pancreatitis by intraperitoneal administration of a high dose of L-arginine in rats. This non-invasive model is highly reproducible and produces selective, dose-dependent acinar cell necrosis. Not only is this a good model to study the pathomechanisms of acute necrotizing pancreatitis, but it is also excellent to observe and influence the time course changes of the disease. By writing this review we iluminate some new aspects of cell physiology and pathology of acute necrotizing pancreatitis. Unfortunately, the reviews about acute experimental pancreatitis usually did not discuss this model. Therefore, the aim of this manuscript was to summarise the observations and address some challenges for the future in L-arginine-induced pancreatitis. PMID:15237423

  13. Experimental investigation of an RNA sequence space

    NASA Technical Reports Server (NTRS)

    Lee, Youn-Hyung; Dsouza, Lisa; Fox, George E.

    1993-01-01

    Modern rRNAs are the historic consequence of an ongoing evolutionary exploration of a sequence space. These extant sequences belong to a special subset of the sequence space that is comprised only of those primary sequences that can validly perform the biological function(s) required of the particular RNA. If it were possible to readily identify all such valid sequences, stochastic predictions could be made about the relative likelihood of various evolutionary pathways available to an RNA. Herein an experimental system which can assess whether a particular sequence is likely to have validity as a eubacterial 5S rRNA is described. A total of ten naturally occurring, and hence known to be valid, sequences and two point mutants of unknown validity were used to test the usefulness of the approach. Nine of the ten valid sequences tested positive whereas both mutants tested as clearly defective. The tenth valid sequence gave results that would be interpreted as reflecting a borderline status were the answer not known. These results demonstrate that it is possible to experimentally determine which sequences in local regions of the sequence space are potentially valid 5S rRNAs.

  14. Origin of SNC kaersutitic amphibole: Experimental data

    NASA Technical Reports Server (NTRS)

    Rutherford, M. J.; Heine, Bruce; Johnson, Marie

    1987-01-01

    The SNC meteorites, a group of cumulus textured, fine grained diabases, pyroxenites, and dunites, appear to have crystallized at relatively shallow depths on the same SNC parent body. Hydrous minerals generally are not present among the cumulus and intercumulus minerals in these meteorites except for some iddingsite alteration of olivine. The presence of hydrous magmatic amphibole in the SNC melt inclusions indicates that crystallization of the melt inclusions had to take place at significant pressure, probably greater than 1 kb based on previous amphibole stability data. If experimental data for kaersutite amphibole were to be obtained, it should be possible to estimate this pressure more precisely then previously, and to estimate the volatile (H2O) content of the parent magma. At this point, the factors controlling the chemistry and stability of high TiO2, kaersutitic amphiboles are not known. In an attempt to determine the factors which control the stability and chemistry of TiO2-rich amphibole, data was refined and extrapolated from four experimental studies of amphibole-melt equilibria recently completed. At the same time, hypothermal experiments were performed on a composition considered to be an early melt in the Shergotty magma liquid line of descent. The latter experiments were an attempt to reproduce crystallization of the amphibole-bearing melt inclusions.

  15. Myoblast fusion: Experimental systems and cellular mechanisms.

    PubMed

    Schejter, Eyal D

    2016-12-01

    Fusion of myoblasts gives rise to the large, multi-nucleated muscle fibers that power and support organism motion and form. The mechanisms underlying this prominent form of cell-cell fusion have been investigated by a variety of experimental approaches, in several model systems. The purpose of this review is to describe and discuss recent progress in the field, as well as point out issues currently unresolved and worthy of further investigation. Following a description of several new experimental settings employed in the study of myoblast fusion, a series of topics relevant to the current understanding of the process are presented. These pertain to elements of three major cellular machineries- cell-adhesion, the actin-based cytoskeleton and membrane-associated elements- all of which play key roles in mediating myoblast fusion. Among the issues raised are the diversity of functions ascribed to different adhesion proteins (e.g. external cell apposition and internal recruitment of cytoskeleton regulators); functional significance of fusion-associated actin structures; and discussion of alternative mechanisms employing single or multiple fusion pore formation as the basis for muscle cell fusion.

  16. Improper ferroelectricity: A theoretical and experimental investigation

    NASA Astrophysics Data System (ADS)

    Hardy, J. R.; Ullman, F. G.

    1984-02-01

    A combined theoretical and experimental study has been made of the origins and properties of the improper ferroelectricity associated with structural modulations of non-zero wavelengths. Two classes of materials have been studied: rare earth molybdates (specifically, gadolinium molybdate: GMO), and potassium selenate and its isomorphs. In the former, the modulation is produced by a zone boundary phonon instability, and in the latter by the instability of a phonon of wave vector approximately two-thirds of the way to the zone-boundary. In the second case the initial result is a modulated structure whose repeat distance is not a rational multiple of the basic lattice repeat distance. This result is a modulated polarization which, when the basic modulation locks in to a rational multiple of the lattice spacing, becomes uniform, and improper ferroelectricity results. The origins of these effects have been elucidated by theoretical studies, initially semi-empirical, but subsequently from first-principles. These complemented the experimental work, which primarily used inelastic light scattering, uniaxial stress, and hydrostatic pressure, to probe the balance between the interionic forces through the effects on the phonons and dielectric properties.

  17. Experimental and clinical experience with distraction osteogenesis.

    PubMed

    Aronson, J

    1994-11-01

    G.A. Ilizarov's clinical insights and experimental biology have developed into what is known today as distraction osteogenesis. Initially used for the treatment of fractures and nonunions, his methods have proven successful for limb lengthening and bone transportation. A brief history of the development of distraction osteogenesis, definition of terms, methods, and monitoring techniques are described. The primary mechanism, intramembranous ossification, is direct bone formation in uniform gradients of mineralization from a central fibrous interzone. New bone is produced from the local host surfaces and quickly remodels to the equivalent macro and microstructure. Blood supply at the focus of distraction, dependency on a latency period, different rates, and rhythms of distraction are all tested and discussed. Data from experimental tibial lengthening in more than 125 animals (dogs, rabbits, and rats) show that distraction osteogenesis provides unlimited new bone formation that remodels at daily rates ranging from 200 to 400 microns. In over 100 clinical cases, patients ranging in age from 18 months to 49 years have regenerated bone at an average rate of 213 microns in adults and 385 microns in children. Approximately 10% of these cases required supplemental bone grafts. The article proposes that distraction osteogenesis might be successfully applied in craniofacial surgery.

  18. Experimental Behavior of Carbon Fiber Reinforced Isolators

    SciTech Connect

    Russo, Gaetano; Pauletta, Margherita; Cortesia, Andrea; Dal Bianco, Alberto

    2008-07-08

    This paper describes an investigation on the experimental behavior of innovative elastomeric isolators reinforced by carbon fiber fabrics. These fabrics are very much lighter than steel plates used in conventional isolators and able to transfer to the adjacent elastomer layers tangential stresses adequate to oppose the transversal deformation of rubber under vertical loads. The isolators are not bonded to the sub- and super-structure (elimination of the steel end-plates), hence their weight and cost are reduced. The experimental investigation is carried out on small-scale isolator prototypes reinforced by quadridirectional carbon fiber fabrics. The isolators are subjected to the following qualification tests prescribed by the Italian Code 'Ordinanza 3274' for steel reinforced isolators: 1) 'Static assessment of the compression stiffness'; 2) 'Static assessment of the shear modulus G'; 3) 'Dynamic assessment of the dynamic shear modulus G{sub din} and of the damping coefficient {xi}; 4) 'Assessment of the G{sub din}-{gamma} and {xi}-{gamma} diagrams by means of dynamic tests'; 5) 'Assessment of creep characteristics'; 6) 'Evaluation of the capacity of sustaining at least 10 cycles'. As a result of the tests, the isolators survived large shear strains, comparable to those expected for conventional isolators.

  19. Fuel-rich, catalytic reaction experimental results

    NASA Technical Reports Server (NTRS)

    Rollbuhler, R. James

    1991-01-01

    Future aeropropulsion gas turbine combustion requirements call for operating at very high inlet temperatures, pressures, and large temperature rises. At the same time, the combustion process is to have minimum pollution effects on the environment. Aircraft gas turbine engines utilize liquid hydrocarbon fuels which are difficult to uniformly atomize and mix with combustion air. An approach for minimizing fuel related problems is to transform the liquid fuel into gaseous form prior to the completion of the combustion process. Experimentally obtained results are presented for vaporizing and partially oxidizing a liquid hydrocarbon fuel into burnable gaseous components. The presented experimental data show that 1200 to 1300 K reaction product gas, rich in hydrogen, carbon monoxide, and light-end hydrocarbons, is formed when flowing 0.3 to 0.6 fuel to air mixes through a catalyst reactor. The reaction temperatures are kept low enough that nitrogen oxides and carbon particles (soot) do not form. Results are reported for tests using different catalyst types and configurations, mass flowrates, input temperatures, and fuel to air ratios.

  20. Numerical and experimental investigation of aeroviscoelastic systems

    NASA Astrophysics Data System (ADS)

    Martins, Polliana C. O.; Guimarães, Thiago A. M.; Pereira, Daniel de A.; Marques, Flávio D.; Rade, Domingos A.

    2017-02-01

    Viscoelastic materials have been widely used for the purpose of passive vibration mitigation in various types of mechanical systems, including, industrial machinery, civil structures and vehicles. In this paper, the use of those materials in aeroelastic systems is investigated, with emphasis placed on the influence of the viscoelastic behavior on the flutter speeds of two-degree-of-freedom typical section models, in which viscoelastic elements are introduced in addition to elastic elements associated to heave and pitch motions. The equations of motion of the aeroelastic system are modified to account for the dependence of the viscoelastic behavior on frequency and temperature, by using the concepts of complex modulus and shift factor. The aerodynamic forces and moments in subsonic regime are modeled according to Theodorsen's method. Numerical simulations are conducted to evaluate the influence of the addition of viscoelastic elements on the flutter speed and elucidate the separated influences of stiffness and damping additions. An experimental wind tunnel setup consisting of a rigid wing supported by flexible elements in pitch and plunge motions has been modified to enable the introduction of viscoelastic elements in parallel to those flexible elements. For various configurations of viscoelastic additions, the flutter instability is characterized from vibration measurements performed for increasing flow speeds in the vicinity of the stability boundary. The experimental results are used to validate the numerical model derived for the aeroviscoelastic system and confirm both qualitatively and quantitatively the predictions of the simulations, especially the possibility of increasing the flutter speed by the inclusion of viscoelastic materials.

  1. Experimental validation of wireless communication with chaos

    NASA Astrophysics Data System (ADS)

    Ren, Hai-Peng; Bai, Chao; Liu, Jian; Baptista, Murilo S.; Grebogi, Celso

    2016-08-01

    The constraints of a wireless physical media, such as multi-path propagation and complex ambient noises, prevent information from being communicated at low bit error rate. Surprisingly, it has only recently been shown that, from a theoretical perspective, chaotic signals are optimal for communication. It maximises the receiver signal-to-noise performance, consequently minimizing the bit error rate. This work demonstrates numerically and experimentally that chaotic systems can in fact be used to create a reliable and efficient wireless communication system. Toward this goal, we propose an impulsive control method to generate chaotic wave signals that encode arbitrary binary information signals and an integration logic together with the match filter capable of decreasing the noise effect over a wireless channel. The experimental validation is conducted by inputting the signals generated by an electronic transmitting circuit to an electronic circuit that emulates a wireless channel, where the signals travel along three different paths. The output signal is decoded by an electronic receiver, after passing through a match filter.

  2. Dynamics of an experimental unconfined aquifer

    NASA Astrophysics Data System (ADS)

    Lajeunesse, E.; Guérin, A.; Devauchelle, O.

    2015-12-01

    During a rain event, water infiltrates into the ground where it flows slowly towards rivers. We use a tank filled with glass beads to simulate this process in a simplified laboratory experiment. A sprinkler pipe generates rain, which infiltrates into the porous material. Groundwater exits this laboratory aquifer through one side of the tank. The resulting water discharge increases rapidly during rainfall, and decays slowly after the rain has stopped.A theoretical analysis based on Darcy's law and the shallow-water approximation reveals two asymptotic regimes. At the beginning of a rain event, the water discharge increases linearly with time, with a slope proportional to the rainfall rate at the power of 3/2. Long after the rain has stopped, it decreases as the inverse time squared, as predicted by Polubarinova-Kochina (1962). These predictions compare well against our experimental data.Field measurements from two distinct catchments exhibit the same asymptotic behaviours as our experiment. This observation suggests that, despite the simplicity of the setup, our experimental results could be extended to natural groundwater flows.

  3. Experimental characterization of aviation-fuel cavitation

    NASA Astrophysics Data System (ADS)

    Dunn, Patrick F.; Thomas, Flint O.; Davis, Michael P.; Dorofeeva, Irina E.

    2010-11-01

    The results of an experimental investigation of the gaseous cavitation of JP-8 aviation fuel in a converging-diverging nozzle are presented. Fuel cavitation is experimentally characterized by high-speed digital imaging, static pressure distributions, and nonintrusive void fraction and bubble velocity measurements. For comparative purposes, experiments were performed using distilled water and dodecane for the same nozzle and nozzle pressure ratios. Dodecane, the largest component of JP-8 by weight, served as its single-component surrogate. For each working fluid, the experiments examined two different flow regimes: an initially single-phase liquid flow in which no cavitation occurred and another that evolved into two-phase cavitating flow. Additional experiments were performed to study the effect of air bubbles injected into either water or JP-8 at the nozzle inlet. For a sufficiently low range of imposed back pressures, gaseous cavitation led to choked flow for each working fluid. The character of the cavitation in the three fluids was different. These differences are highlighted and plausible mechanisms responsible for the observed behavior are discussed.

  4. [Animal experimentation, animal welfare and scientific research].

    PubMed

    Tal, H

    2013-10-01

    Hundreds of thousands of laboratory animals are being used every year for scientific experiments held in Israel, mostly mice, rats, rabbits, guinea pigs, and a few sheep, cattle, pigs, cats, dogs, and even a few dozen monkeys. In addition to the animals sacrificed to promote scientific research, millions of animals slain every year for other purposes such as meat and fine leather fashion industries. While opening a front against all is an impossible and perhaps an unjustified task, the state of Israel enacted the Animal Welfare (Animal Experimentation) Law (1994). The law aims to regulate scientific animal experiments and to find the appropriate balance between the need to continue to perform animal experiments for the advancement of research and medicine, and at the same time to avoid unnecessary trials and minimize animal suffering. Among other issues the law deals with the phylogenetic scale according to which experimental animals should be selected, experiments for teaching and practicing, and experiments for the cosmetic industry. This article discusses bioethics considerations in animal experiments as well as the criticism on the scientific validity of such experiments. It further deals with the vitality of animal studies and the moral and legal obligation to prevent suffering from laboratory animals.

  5. Colonic perianastomotic carcinogenesis in an experimental model

    PubMed Central

    Pérez-Holanda, Sergio; Rodrigo, Luis; Pinyol-Felis, Carme; Vinyas-Salas, Joan

    2008-01-01

    Background To examine the effect of anastomosis on experimental carcinogenesis in the colon of rats. Methods Forty-three 10-week-old male and female Sprague-Dawley rats were operated on by performing an end-to-side ileorectostomy. Group A:16 rats received no treatment. Group B: 27 rats received 18 subcutaneous injections weekly at a dose of 21 mg/kg wt of 1–2 dimethylhydrazine (DMH), from the eighth day after the intervention. Animals were sacrificed between 25–27 weeks. The number of tumours, their localization, size and microscopic characteristics were recorded. A paired chi-squared analysis was performed comparing tumoral induction in the perianastomotic zone with the rest of colon with faeces. Results No tumours appeared in the dimethylhydrazine-free group. The percentage tumoral area was greater in the perianastomotic zone compared to tumours which had developed in the rest of colon with faeces (p = 0.014). Conclusion We found a cocarcinogenic effect due to the creation of an anastomosis, when using an experimental model of colonic carcinogenesis induced by DMH in rats. PMID:18667092

  6. Bone healing under experimental anemia in rats.

    PubMed

    Giglio, M J; Gorustovich, A; Guglielmotti, M B

    2000-01-01

    The effects of anemia on different physiological parameters have been the object of permanent study. There are no studies in the literature on the effects of this disorder on the process on bone healing. The aim of the present study was to evaluate, histologically and histomorphometrically, the process of osteogenesis in the post-extraction alvcolus of the lower molar, and in the peri-implant environment of rats. Twenty male Wistar rats (body weight (b.w.): 60 +/- 7 g) were grouped into two experimental sets. The control group (n:10) was given 0.5 mL saline solution i.p. The anemic group (n:10) was injected with 6 mg/100 g of b.w. or 3 mg/100 g b.w. phenylhidrazine, a well known hemolytic agent. Under ketamine-xylazine anesthesia the rats were submitted to extraction of the first lower molars, and to implantation in the tibia in keeping with the "laminar test" procedure. Other parameters, i.e. body weight (b.w.), food intake (FI), hematocrit (Htc), and hemoglobinemia (Hb) were monitored every 48 hs. The results showed a reduction in b.w., FI, Htc and Hb in the experimental group. The histological and histomorphometrical data show that the condition of anemia affects osteogenesis quali-quantitatively in the post-extraction alveolus and peri-implant microenvironment. Both bone reparative situations showed that ostegenesis is "sensitive" to anemia and/or the associated conditions, causing a delay in bone healing.

  7. EXPERIMENTAL ATHEROSCLEROSIS AND CARDIAC INFARCTS IN RATS

    PubMed Central

    Wilgram, George F.

    1959-01-01

    Marked obesity was induced in rats by feeding a high fat, egg yolk-rich diet. The obese rats were hyperlipemic and showed an increased incidence of lipomatous coronary lesions, but did not develop severe atheromatous lesions. Spontaneous vascular lesions of several kinds have been observed in aging rats. Among them, plaques containing a fibrin-like material seem to be conspicuous. However, these lesions differ from the experimentally induced changes, which were more fatty. Atherosclerosis, as it is defined in human pathology, has not been observed to develop spontaneously in rats. Experimental induction of marked hyperlipemia and hypercholesterolemia by feeding a high fat egg yolk-rich diet (supplemented with cholesterol, choleate, and thiouracil), and use of viosterol to cause vascular injury, led to severe atherosclerosis, coronary occlusion, and myocardial infarction. A consideration of all the findings reported here leads to renewed support of the concept that atherosclerosis has a combination of causes (Aschoff, Anitschkow, Page). Of all the etiological factors considered here, elevation of blood lipides and vascular injury are thought to be the most important ones. PMID:13620855

  8. [Experimental whooping cough of nonhuman primate].

    PubMed

    Kubrava, D T; Medkova, A Iu; Siniashina, L N; Shevtsova, Z V; Matua, A Z; Kondzharia, I G; Barkaia, V S; Elistratova, Zh V; Karataev, G I; Mikvabia, Z Ia; Gintsburg, A L

    2013-01-01

    Despite considerable success in study of Bordetella pertussis virulence factors, pathogenesis of whooping cough, duration of B. pertussis bacteria persistence, types and mechanisms of immune response are still keep underinvestigated. It can be explained by the absence ofadequate experimental animal model for pertussis study. Our study estimates clinical and laboratory parameters of whooping cough in non-human primates of the Old World in the process of intranasan infection by virulent B. pertussis bacteria. Also the duration of B. pertussis bacteria persistence in animals was investigated. 14 animal units of 4 species of non-human primates of the Old World were used for intranasal infection. The examination of infect animals included: visual exploration of nasopharynx, thermometry, clinical and biochemical blood analyses, identification ofB. pertussis, using microbiologic and molecular genetic analyses, estimation of innate and adoptive immune factors. The development of infectious process was accompanied by generation of B. pertussis bacteria, catarrhal inflammation of nasopharyngeal mucosa, leucocytosis, hypoglycemia specific for pertussis, and activation of innate and adaptive immunity for all primates regardless of specie were seen. While repeated experimental infection in primates single bacterial colonies were registered during only first week after challenge. It occurs like the absence of inflammation of nasopharyngeal mucosa and the lack of laboratory marks of whooping cough, recorded after first challenge. The evident booster effect of humoral immunity was observed. As a model for investigation of B. pertussis bacteria persistence and immune response against whooping cough we suggest the usage of rhesus macaque as more available to experiments.

  9. Novel cooperation experimentally evolved between species.

    PubMed

    Harcombe, William

    2010-07-01

    Cooperation violates the view of "nature red in tooth and claw" that prevails in our understanding of evolution, yet examples of cooperation abound. Most work has focused on maintenance of cooperation within a single species through mechanisms such as kin selection. The factors necessary for the evolutionary origin of aiding unrelated individuals such as members of another species have not been experimentally tested. Here, I demonstrate that cooperation between species can be evolved in the laboratory if (1) there is preexisting reciprocation or feedback for cooperation, and (2) reciprocation is preferentially received by cooperative genotypes. I used a two species system involving Salmonella enterica ser. Typhimurium and an Escherichia coli mutant unable to synthesize an essential amino acid. In lactose media Salmonella consumes metabolic waste from E. coli, thus creating a mechanism of reciprocation for cooperation. Growth in a spatially structured environment assured that the benefits of cooperation were preferentially received by cooperative genotypes. Salmonella evolved to aid E. coli by excreting a costly amino acid, however this novel cooperation disappeared if the waste consumption or spatial structure were removed. This study builds on previous work to demonstrate an experimental origin of interspecific cooperation, and to test the factors necessary for such interactions to arise.

  10. Experimental one-way quantum computing.

    PubMed

    Walther, P; Resch, K J; Rudolph, T; Schenck, E; Weinfurter, H; Vedral, V; Aspelmeyer, M; Zeilinger, A

    2005-03-10

    Standard quantum computation is based on sequences of unitary quantum logic gates that process qubits. The one-way quantum computer proposed by Raussendorf and Briegel is entirely different. It has changed our understanding of the requirements for quantum computation and more generally how we think about quantum physics. This new model requires qubits to be initialized in a highly entangled cluster state. From this point, the quantum computation proceeds by a sequence of single-qubit measurements with classical feedforward of their outcomes. Because of the essential role of measurement, a one-way quantum computer is irreversible. In the one-way quantum computer, the order and choices of measurements determine the algorithm computed. We have experimentally realized four-qubit cluster states encoded into the polarization state of four photons. We characterize the quantum state fully by implementing experimental four-qubit quantum state tomography. Using this cluster state, we demonstrate the feasibility of one-way quantum computing through a universal set of one- and two-qubit operations. Finally, our implementation of Grover's search algorithm demonstrates that one-way quantum computation is ideally suited for such tasks.

  11. Upper washita river experimental watersheds: physiography data.

    PubMed

    Moriasi, Daniel N; Starks, Patrick J; Steiner, Jean L; Guzman, Jorge A; Allen, Paul B; Naney, James W

    2014-07-01

    Physiographic data such as digital elevation models (DEMs), soils, geology, stream channel network characteristics, channel stability, and land use data are essential for understanding the complex hydrologic cycle and chemical transport processes of any given study area. We describe the physiographic data available in the Little Washita River Experimental Watershed (LWREW) and Fort Cobb Reservoir Experimental Watershed (FCREW) in Oklahoma. Specifically, we describe (i) available raw and post-processed DEM products (), (ii) available soils data ( and ) and associated error analysis based on limited measured data, (iii) geologic formations in the LWREW and FCREW ( and ), and (iv) available rapid geomorphic assessment measurements () and their uses. Data collection is a collaborative effort among USGS, NRCS, and ARS. These data sets have been used for several research applications by USDA-ARS scientists and researchers from other institutions and agencies. Plans for detailed geomorphic assessment of stream channel networks in the FCREW are underway in collaboration with Oklahoma State University in Stillwater. The collected data will enable updating of the channel stability stage condition since there have been several major rainfall events in the watershed since the last geomorphic assessment.

  12. THE EXPERIMENTAL TRANSMISSION OF COLORADO TICK FEVER.

    PubMed

    Florio, L; Stewart, M O; Mugrage, E R

    1944-09-01

    1. The symptoms, history of tick bite, characteristic fever curve, and white blood cell picture should enable the physician to make a diagnosis of Colorado tick fever in nearly every case. 2. The typical white blood cell picture is a depression of the total leucocytes with a shift to the left of the granulocytes. Basophilic cytoplasmic bodies appear occasionally in lymphocytes 3 to 4 days after clinical recovery. 3. The disease can be transmitted serially in human beings by parenteral injection of blood or serum. Such transfers have not resulted in decreased or increased virulence. 4. The naturally acquired and experimental cases of Colorado tick fever are identical in their manifestations. 5. An attack of Colorado tick fever confers a degree of definite immunity to the disease. 6. Colorado tick fever is not a mild form of Rocky Mountain spotted fever since individuals immunized with ground tick vaccine against Rocky Mountain spotted fever are still susceptible to Colorado tick fever. 7. Adult Dermacentor andersoni ticks allowed to feed on typical cases, then carried through to a new generation and fed on susceptible adults, failed to transmit the disease. 8. Colorado tick fever has been successfully transmitted to an experimental animal, the golden hamster.

  13. Experimental enhancement of pickleweed, Suisun Bay, California

    USGS Publications Warehouse

    Miles, A. Keith; Van Vuren, Dirk H.; Tsao, Danika C.; Yee, Julie L.

    2015-01-01

    As mitigation for habitat impacted by the expansion of a pier on Suisun Bay, California, two vehicle parking lots (0.36 ha and 0.13 ha) were restored by being excavated, graded, and contoured using dredged sediments to the topography or elevation of nearby wetlands. We asked if pickleweed (Sarcocornia pacifica L, [Amaranthaceae]) colonization could be enhanced by experimental manipulation on these new wetlands. Pickleweed dominates ecologically important communities at adjacent San Francisco Bay, but is not typically dominant at Suisun Bay probably because of widely fluctuating water salinity and is outcompeted by other brackish water plants. Experimental treatments (1.0-m2 plots) included mulching with pickleweed cuttings in either the fall or the spring, tilling in the fall, or applying organic enrichments in the fall. Control plots received no treatment. Pickleweed colonization was most enhanced at treatment plots that were mulched with pickleweed in the fall. Since exotic vegetation can colonize bare sites within the early phases of restoration and reduce habitat quality, we concluded that mulching was most effective in the fall by reducing invasive plant cover while facilitating native plant colonization.

  14. Eating disorders need more experimental psychopathology.

    PubMed

    Jansen, Anita

    2016-11-01

    Eating disorders are severe and disabling mental disorders. The scientific study of eating disorders has expanded dramatically over the past few decades, and provided significant understanding of eating disorders and their treatments. Those significant advances notwithstanding, there is scant knowledge about key processes that are crucial to clinical improvement. The lack of understanding mechanisms that cause, maintain and change eating disorders, currently is the biggest problem facing the science of eating disorders. It hampers the development of really effective interventions that could be fine-tuned to target the mechanisms of change and, therefore, the development of more effective treatments. It is argued here that the science of eating disorders and eating disorder treatment could benefit tremendously from pure experimental studies into its mechanisms of change, that is, experimental psychopathology (EPP). To illustrate why eating disorders need more EPP research, some key symptoms - restriction of intake, binge eating and body overvaluation - will be discussed. EPP studies challenge some generally accepted views and offer a fresh new look at key symptoms. This will, consequently, better inform eating disorder treatments.

  15. Involving students in experimental design: three approaches.

    PubMed

    McNeal, A P; Silverthorn, D U; Stratton, D B

    1998-12-01

    Many faculty want to involve students more actively in laboratories and in experimental design. However, just "turning them loose in the lab" is time-consuming and can be frustrating for both students and faculty. We describe three different ways of providing structures for labs that require students to design their own experiments but guide the choices. One approach emphasizes invertebrate preparations and classic techniques that students can learn fairly easily. Students must read relevant primary literature and learn each technique in one week, and then design and carry out their own experiments in the next week. Another approach provides a "design framework" for the experiments so that all students are using the same technique and the same statistical comparisons, whereas their experimental questions differ widely. The third approach involves assigning the questions or problems but challenging students to design good protocols to answer these questions. In each case, there is a mixture of structure and freedom that works for the level of the students, the resources available, and our particular aims.

  16. Experimental research on seismoelectric effects in sandstone

    NASA Astrophysics Data System (ADS)

    Peng, Rong; Wei, Jian-Xing; Di, Bang-Rang; Ding, Pin-Bo; Liu, Zi-Chun

    2016-09-01

    The seismoelectric effects induced from the coupling of the seismic wave field and the electromagnetic field depend on the physical properties of the reservoir rocks. We built an experimental apparatus to measure the seismoelectric effects in saturated sandstone samples. We recorded the seismoelectric signals induced by P-waves and studied the attenuation of the seismoelectric signals induced at the sandstone interface. The analysis of the seismoelectric effects suggests that the minimization of the potential difference between the reference potential and the baseline potential of the seismoelectric disturbance area is critical to the accuracy of the seismoelectric measurements and greatly improves the detectability of the seismoelectric signals. The experimental results confirmed that the seismoelectric coupling of the seismic wave field and the electromagnetic field is induced when seismic wave propagating in a fluid-saturated porous medium. The amplitudes of the seismoelectric signals decrease linearly with increasing distance between the source and the interface, and decay exponentially with increasing distance between the receiver and the interface. The seismoelectric response of sandstone samples with different permeabilities suggests that the seismoelectric response is directly related to permeability, which should help obtaining the permeability of reservoirs in the future.

  17. The new experimental areas oxygen monitor

    SciTech Connect

    Schoo, D.

    1988-08-01

    Because of the nature of the beamline requirements for oxygen monitoring equipment to operate ancillary equipment, such as exhaust fans, doors and cryogenic valves, and because of the well known problems of the oxygen sensors installed in high radiation areas, a new design for sensing the oxygen content of ambient air was needed. A new monitor system was designed to solve these problems and some others that compromised the reliability and the maintenance of the monitoring system. From the operating experience gained with the Accelerator Standard Oxygen Monitor System currently installed in many locations in the experimental area, from suggestions solicited from the Safety Group and from the Cryogenics Group, I designed a new Experimental Areas Standard Oxygen Monitor. Many suggestions were carefully considered and a design that incorporates most of them was constructed. I will summarize a list of the important improvements that will be of interest to the users of the system, and explain how these functions will make the oxygen system easier to live with. 2 figs.

  18. Development of Experimental Vaccines Against Liver Flukes.

    PubMed

    Yap, Huan Yong; Smooker, Peter M

    2016-01-01

    A multitude of experimental vaccines have been developed against liver flukes in the past. However, there has yet to be the development of a commercial livestock vaccine. Reasons for this may be multiple, and include the lack of identification of the best antigen(s), or the immune response induced by those antigens not being appropriate in either magnitude or polarity (and therefore not protective). Cathepsin proteases are the major component of the excretory/secretory (ES) material of liver flukes in all stages of their life cycle in the definitive host and are the primary antigens of interest for the vaccine development in many studies. Hence, this chapter presents the methodologies of using cathepsin proteases as targeted antigens in recombinant protein and DNA vaccine development to engender protective immune responses against fasciolosis.First, the experimental vaccines developed in the past and the criteria of an effective vaccine for fasciolosis are briefly reviewed. Then flowcharts for recombinant protein vaccine and DNA vaccine development are presented, followed by the detailed materials and methodologies.

  19. Testing Numerical Dynamo Models Against Experimental Results

    NASA Astrophysics Data System (ADS)

    Gissinger, C. J.; Fauve, S.; Dormy, E.

    2007-12-01

    Significant progress has been achieved over the past few years in describing the geomagnetic field using computer models for dynamo action. Such models are so far limited to parameter regimes which are very remote from actual values relevant to the Earth core or any liquid metal (the magnetic Prandtl number is always over estimated by a factor at least 104). While existing models successfully reproduce many of the magnetic observations, it is difficult to assert their validity. The recent success of an experimental homogeneous unconstrained dynamo (VKS) provides a new way to investigate dynamo action in turbulent conducting flows, but it also offers a chance to test the validity of exisiting numerical models. We use a code originaly written for the Geodynamo (Parody) and apply it to the experimental configuration. The direct comparison of simulations and experiments is of great interest to test the predictive value of numerical simulations for dynamo action. These turbulent simulations allow us to approach issues which are very relevant for geophysical dynamos, especially the competition between different magnetic modes and the dynamics of reversals.

  20. Experimental and theoretical approaches to conscious processing.

    PubMed

    Dehaene, Stanislas; Changeux, Jean-Pierre

    2011-04-28

    Recent experimental studies and theoretical models have begun to address the challenge of establishing a causal link between subjective conscious experience and measurable neuronal activity. The present review focuses on the well-delimited issue of how an external or internal piece of information goes beyond nonconscious processing and gains access to conscious processing, a transition characterized by the existence of a reportable subjective experience. Converging neuroimaging and neurophysiological data, acquired during minimal experimental contrasts between conscious and nonconscious processing, point to objective neural measures of conscious access: late amplification of relevant sensory activity, long-distance cortico-cortical synchronization at beta and gamma frequencies, and "ignition" of a large-scale prefronto-parietal network. We compare these findings to current theoretical models of conscious processing, including the Global Neuronal Workspace (GNW) model according to which conscious access occurs when incoming information is made globally available to multiple brain systems through a network of neurons with long-range axons densely distributed in prefrontal, parieto-temporal, and cingulate cortices. The clinical implications of these results for general anesthesia, coma, vegetative state, and schizophrenia are discussed.