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Добірка наукової літератури з теми "Ondes X"

Автор: Grafiati

Опубліковано: 7 вересня 2022

Оновлено: 18 вересня 2022

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Статті в журналах з теми "Ondes X"

Ribaud, Francis, and Abdellah Youssfi. "Solutions globales et solutions auto-similaires de l'équation des ondes non linéaire." Comptes Rendus de l'Académie des Sciences - Series I - Mathematics 329, no. 1 (July 1999): 33–36. http://dx.doi.org/10.1016/s0764-4442(99)80456-x.

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Ouahsine, Abdellatif, and adim Pavlov. "Un modèle du spectre des ondes de surface générées par le vent." Comptes Rendus de l'Académie des Sciences - Series IIB - Mechanics-Physics-Astronomy 327, no. 10 (September 1999): 1011–14. http://dx.doi.org/10.1016/s1287-4620(00)87012-x.

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D'Agostino, Par S. "Pourquoi Hertz et non pas Maxwell, a-t-il découvert les ondes électriques?" Centaurus 32, no. 1 (April 1989): 66–76. http://dx.doi.org/10.1111/j.1600-0498.1989.tb00840.x.

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Lottmann, H., O. Traxer, F. Archambaud, B. Helal, and B. Mercier-Pageyral. "Scintigraphie au DMSA après lithotritie extracorporelle par ondes de choc (LECOC) chez l'enfant." Journal de Pédiatrie et de Puériculture 12, no. 2 (March 1999): 94–99. http://dx.doi.org/10.1016/s0987-7983(99)80228-x.

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Bonod, Nicolas. "Physicien célèbre : Max von Laue." Photoniques, no. 98 (September 2019): 18–19. http://dx.doi.org/10.1051/photon/20199818.

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Анотація:

Max von Laue est un physicien théoricien allemand spécialiste de la diffraction des ondes, de la relativité et de la superconductivité. Il propose en 1912 de sonder l’arrangement périodique de la matière avec des faisceaux de courtes longueurs d’onde, les rayons X ; et sera récompensé par le prix Nobel de Physique en 1914. La découverte de la diffraction des rayons X par des cristaux sera à l’origine d’avancées majeures dans les 100 ans qui suivirent, de la découverte de la structure de l’ADN à celle des quasi-cristaux.

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Ibrahim, Slim, and Mohamed Majdoub. "Existence globale de solutions pour l'équation des ondes semi-linéaire critique à coefficients variables." Comptes Rendus de l'Académie des Sciences - Series I - Mathematics 328, no. 7 (April 1999): 579–84. http://dx.doi.org/10.1016/s0764-4442(99)80250-x.

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Grimal, Quentin, Salah Naili, and Alexandre Watzky. "Impact non-pénétrant sur le thorax : influence de la courbure sur la propagation des ondes." Comptes Rendus Mécanique 330, no. 8 (January 2002): 569–74. http://dx.doi.org/10.1016/s1631-0721(02)01505-x.

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Guillou, Sylvain, Nathaly Barbry, and Kim Dan Nguyen. "Calcul numérique des ondes de surface par une méthode de projection avec un maillage eulérien adaptatif." Comptes Rendus de l'Académie des Sciences - Series IIB - Mechanics 328, no. 12 (December 2000): 875–81. http://dx.doi.org/10.1016/s1620-7742(00)01268-x.

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Brignol, Arnaud, Farida Cheriet, and Catherine Laporte. "Extraction automatique de repères vertébraux à partir d’échographies." médecine/sciences 37 (November 2021): 22–24. http://dx.doi.org/10.1051/medsci/2021186.

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Анотація:

Certaines formes de myopathies telles que la dystrophie musculaire de Duchenne entraînent une dégénérescence progressive des muscles chez le patient. Ceci se traduit par l’apparition d’une scoliose dont la gravité augmente au cours du temps. La norme clinique pour le suivi de la scoliose consiste à réaliser un examen radiographique. Malheureusement, l’exposition répétée aux rayons X est nocive pour la santé du patient. L’échographie est une technique d’imagerie médicale non irradiante qui utilise des ondes ultrasonores (US). Cependant, l’interprétation des échographies de vertèbres est souvent difficile en raison de la qualité variable des images. En réponse à ce défi, nous présentons une méthode pour localiser automatiquement les vertèbres sur les échographies. La validation de cette approche reproductible laisse à penser qu’il serait possible, à terme, de remplacer une partie des examens radiographiques standards par l’échographie.

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Lefeuvre, F., M. Parrot, J. L. Rauch, B. Poirier, A. Masson, and M. Mogilevsky. "Preliminary results from the MEMO multicomponent measurements of waves on-board INTERBALL 2." Annales Geophysicae 16, no. 9 (September 30, 1998): 1117–36. http://dx.doi.org/10.1007/s00585-998-1117-3.

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Abstract. The MEMO (MEsure Multicomposante des Ondes) experiment is a part of the INTERBALL 2 wave consortium. It is connected to a total of six electric and nine magnetic independent sensors. It provides waveforms associated with the measurement of two to five components in three frequency bands: ELF (5–1000 Hz), VLF (1–20 kHz), LF (20–250 kHz). Preliminary analyses of low and high resolution data are presented. The emphasis is put on the estimation of the propagation characteristics of the observed waves.VLF hiss emissions are shown to be mainly whistler mode emissions, but other modes are present. An accurate estimation of the local plasma frequency is proposed when the low L = 0 cutoff frequency is identified. AKR emissions observed just above source regions are studied. R-X and L-O modes are found: the first at the lowest frequencies and the second at the highest. Both propagate with wave normal directions weakly oblique or quasi-parallel to the Earth's magnetic field direction. Propagation characteristics are also determined for a (non-drifting) fine structure of AKR. There is no fundamental difference with structurless events. Nightside and dayside bursts of ELF electromagnetic emissions are presented. It is not clear whether the two emissions belong to the "lion roar" emissions or not.Key words. Magnetospheric physics (auroral phenomena; plasma waves and instabilities; instruments and techniques)

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Дисертації з теми "Ondes X"

Pinsolle, Edouard. "Etude des ondes de densité de charge par diffraction cohérente des rayons X." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00789152.

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Les matériaux à Onde de Densité de Charge (ODC) ont été très étudiés durant les années 80 pour leurs propriétés de transport remarquables. Pourtant il reste plusieurs questions sans réponse. L'utilisation de nouvelles techniques expérimentales permet de répondre à certaines de ces questions. Après avoir présenté les principes de base de la Diffraction Cohérente des Rayons X (DCRX), nous montrons, en prenant comme exemple l'étude des boucles de dislocation dans le silicium, comment cette technique expérimentale permet de sonder les défauts de phase présents dans les cristaux.Nous poursuivons par des expériences sur les composés NbSe3 et K0.3MoO3 qui se trouvent être des systèmes canoniques pour l'étude des ODC. Nous montrons notamment grâce à la DCRX l'influence des défauts dans le glissement d'une ODC dans le composé NbSe3.Pour finir nous présentons des expériences sur la coexistence entre les ODC et onde de densité de spin dans le Chrome ainsi que la coexistence des ODC et de la supraconductivité dans le composé NbSe2. Ces expériences préliminaires laissent à penser que la supraconductivité augmente la cohérence de l'ODC et que la transition de spin flip, présente dans le Chrome, a des effets sur l'ODC.

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Ouzer, Nabil Adam. "Optimisation d'un isolateur coplanaire à déplacement de champ et ondes magnétostatiques opérant en bande X." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSES026/document.

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Optimisation d’un isolateur coplanaire à déplacement de champ et ondes magnétostatiques opérant en bande X. Résumé en français non fourni
Optimization of an isolator coplanar field displacement and waves magnetostatic operating in X-band. English abstract not supplied

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Ben, Jabrallah Soumaya. "Electrolytes aux interfaces : accès aux premiers nanomètres par la technique des ondes stationnaires." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066709/document.

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La distribution des ions et des charges aux interfaces solide-liquide est d'une importance capitale dans de nombreux phénomènes et processus. En particulier, le développement de la microfluidique a renforcé la nécessité de comprendre et de contrôler les distributions d'ions dans la double couche électrique. En effet, les phénomènes qui se produisent dans la couche diffuse de Gouy-Chapman deviennent dominants dans la détermination des propriétés d'écoulement lorsque les tailles de canaux deviennent comparables à la longueur de Debye. Dans ce travail de thèse, nous avons utilisé la technique des ondes stationnaire de rayons X pour déterminer la distribution interfaciale d’ions. Nous avons développé des cellules de quelques centaines de nanomètres voir moins dont l’épaisseur est mesurée précisément par réflectivité des rayons X. Dans ces cellules, avons confiné le film liquide entre les multicouches qui permettent de créer l'onde stationnaire et un film polymère. La fluorescence des ions dans ce champ permet alors d’extraire leur distribution aux interfaces avec une résolution spatiale de quelques Angströms. Ce travail a été réalisé pour plusieurs solutions contenant différents mélanges d'ions monovalents (Chlorure, Potassium, Césium et Iode) à plusieurs concentrations. Dans une deuxième partie de ce travail, nous présentons les résultats pour des chlorures de lanthanides. Ces études nous ont permis de déterminer la composition de la couche de Stern et la distribution des ions au sein de cette couche pour l'ensemble des paires La3+/Ce3+, La3+/Eu3+, La3+/Gd3+, Ce3+/Eu3+, Ce3+/Gd3+ et Eu3+/Gd3+. Nous avons pu alors classer ces différents ions et discuter le classement
The distribution of ions and charges at solid-water interfaces is of key importance in a number of phenomena and processes. In particular the development of microfluidics has strengthened the need for understanding and controlling ion distributions in the electric double layer. Indeed, phenomena occurring within the diffuse Gouy-Chapman layer become dominant in determining flow properties as channel size become on the same order of magnitude of the Debye length. In this thesis, we used the technique of X-ray standing waves to determine the distribution of interfacial ions. We have developed cells with thicknesses of a few hundred nanometers or less, precisely measured by X-ray reflectivity. The liquid film is confined between the multilayer which create the standing wave and a polymer film. The ion fluorescence allows to determine the interfacial distribution with a spatial resolution of a few Angstroms. This work was carried out for solutions containing different mixtures of monovalent ions (chloride, potassium, cesium and iodine) at several concentrations.In the second part of this work, we present the results for lanthanide chlorides. These studies have allowed us to determine the composition of the Stern layer and the distribution of ions in this layer for all pairs La3+/Ce3+, La3+/Eu3+, La3+/Gd3+, Ce3+/Eu3+, Ce3+/Gd3+ et Eu3+/Gd3+. We could then classify these ions and discuss the series

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TUCOULOU, TACHOUERES REMI. "Modulation spatiale et temporelle d'un faisceau de rayons x par interaction avec des ondes acoustiques de surface." Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10273.

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La reflexion d'un faisceau x ( 1 a) sur la surface d'un cristal piezoelectrique (linbo#3) excite par des ondes acoustiques s'accompagne de par et d'autre du faisceau reflechi de pics satellites intenses (15% de l'intensite du faisceau direct) dus a la rugosite sinusoidale de la surface. Un phenomene similaire s'observe autour des diffractions de bragg d'une multicouche deposee sur un cristal piezoelectrique dont la surface est parcourue par des ondes acoustiques. Nous avons montre que la position angulaire de ces pics satellites depend de l'angle d'incidence et du rapport des longueurs d'onde x et acoustique et pouvait donc etre modifiee en changeant la frequence acoustique. Ceci nous a conduit a developper une premiere application permettant le balayage spatial d'un faisceau x par variation de la frequence acoustique autour de la frequence de resonance de l'emetteur. Ce balayage a une ou deux dimensions si l'on associe deux deflecteurs acoustiques, peut atteindre 1 mm a une distance de 1 m du cristal avec une sensibilite de l'ordre du nanometre, bien inferieure aux dimensions actuelles des faisceaux (de l'ordre de 1 m#2). Nous avons mene une etude sur l'association d'un systeme electro-acoustique avec une optique focalisante (lentille de bragg-fresnel) pour obtenir des balayages de faisceaux focalises. Les utilisations possibles sont dans la microanalyse, la microscopie x et la lithogravure. La seconde application presentee dans cette these consiste a introduire une pulsation de la structure temporelle de l'onde acoustique afin d'obtenir une modulation temporelle de l'intensite des faisceaux x satellites. Une utilisation interessante est le selecteur haute frequence de pulses synchrotrons realise en synchronisant les pulses acoustiques sur la frequence des paquets d'electrons qui tournent dans l'anneau. Ce filtre temporel elimine 99% des photons indesirables. Ces faisceaux adaptables sont utiles pour les experiences resolues en temps

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Vérité, Marc. "Etude de dépots de ferrite pour dispositifs intégrés micro-ondes non réciproques." Limoges, 2002. http://aurore.unilim.fr/theses/nxfile/default/88d2bfa0-11e2-4e82-a478-a02d532d3c37/blobholder:0/2002LIMO0026.pdf.

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Cette thèse a permis d'optimiser les propriétés de couches épaisses d'hexaferrite de baryum, obtenues par évaporation au canon à électrons, en vue de la conception d'un circulateur intégré en technologie MMIC. Cette étude montre que lorsque la température des substrats est de 700°Cles dépôts sont cristallisés. Selon les conditions d'évaporation il est possible d'observer soit la phase pure : BaFe12O19, soit un mélange de phases : BaFe12O19 + BaFe2O4. De plus, nous constatons une orientation préférentielle dans le plan de la couche. Les propriétés magnétiques mesurées sont acceptables pour l'application visée. Nous avons aussi mis en évidence un phénomène d'évaporation préférentielle qui ne permet pas de réaliser un transfert stoechiométrique du lingot aux substrats. La solution envisagée est de s'équiper d'un bâti d'évaporation comportant plusieurs sources différentes. Enfin, nous nous sommes intéressés à la méthode des plans d'expériences
During this thesis, barium hexaferrite thick films properties have been optimized. Films are realized by electron beam evaporation and the final goal is to make an integrated circulator functionning at 70 GHz. We have observed that the layers are crystallized when substrates temperature is equal to 700ʿC, with in-plane preferential orientation. Moreover, we have observed a pure BaFe12O19 phase or a mixture of phases : BaFe12O19 + BaFe2O4. All measured magnetic properties are acceptable for the application. We have also observed a preferential evaporation phenomenon. The solution consists to use a three beams evaporation system to evaporate separately barium oxide and iron oxide to control the iron on barium ratio. Finally, we have investigated the Thaguchi method

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Caron, Francis. "Modélisation en bandes C et X de la rétrodiffusion de couverts de neige sèche : évaluation de l’apport de l’approximation quasi-cristalline pour les milieux denses." Mémoire, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8897.

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La compréhension et la modélisation de l’interaction de l’onde électromagnétique avec la neige sont très importantes pour l’application des technologies radars à des domaines tels que l’hydrologie et la climatologie. En plus de dépendre des propriétés de la neige, le signal radar mesuré dépendra aussi des caractéristiques du capteur et du sol. La compréhension et la quantification des différents processus de diffusion du signal dans un couvert nival s’effectuent à travers les théories de diffusions de l’onde électromagnétique. La neige, dans certaines conditions, peut être considérée comme un milieu dense lorsque les particules de glace qui la composent y occupent une fraction volumique considérable. Dans un tel milieu, les processus de diffusion par les particules ne se font plus de façon indépendante, mais de façon cohérente. L’approximation quasi-cristalline pour les milieux denses est une des théories élaborées afin de prendre en compte ces processus de diffusions cohérents. Son apport a été démontré dans de nombreuses études pour des fréquences > 10 GHz où l’épaisseur optique de la neige est importante et où la diffusion de volume est prédominante. Par contre, les capteurs satellitaires radar présentement disponibles utilisent les bandes L (1-2GHz), C (4-8GHz) et X (8-12GHz), à des fréquences principalement en deçà des 10 GHz. L’objectif de la présente étude est d’évaluer l’apport du modèle de diffusion issu de l’approximation quasi-cristalline pour les milieux denses (QCA/DMRT) dans la modélisation de couverts de neige sèches en bandes C et X. L’approche utilisée consiste à comparer la modélisation de couverts de neige sèches sous QCA/DMRT à la modélisation indépendante sous l’approximation de Rayleigh. La zone d’étude consiste en deux sites localisés sur des milieux agricoles, près de Lévis au Québec. Au total 9 champs sont échantillonnés sur les deux sites afin d’effectuer la modélisation. Dans un premier temps, une analyse comparative des paramètres du transfert radiatif entre les deux modèles de diffusion a été effectuée. Pour des paramètres de cohésion inférieurs à 0,15 à des fractions volumiques entre 0,1 et 0,3, le modèle QCA/DMRT présentait des différences par rapport à Rayleigh. Un coefficient de cohésion optimal a ensuite été déterminé pour la modélisation d’un couvert nival en bandes C et X. L’optimisation de ce paramètre a permis de conclure qu’un paramètre de cohésion de 0,1 était optimal pour notre jeu de données. Cette très faible valeur de paramètre de cohésion entraîne une augmentation des coefficients de diffusion et d’extinction pour QCA/DMRT ainsi que des différences avec les paramètres de Rayleigh. Puis, une analyse de l’influence des caractéristiques du couvert nival sur les différentes contributions du signal est réalisée pour les 2 bandes C et X. En bande C, le modèle de Rayleigh permettait de considérer la neige comme étant transparente au signal à des angles d’incidence inférieurs à 35°. Vu l’augmentation de l’extinction du signal sous QCA/DMRT, le signal en provenance du sol est atténué d’au moins 5% sur l’ensemble des angles d’incidence, à de faibles fractions volumiques et fortes tailles de grains de neige, nous empêchant ainsi de considérer la transparence de la neige au signal micro-onde sous QCA/DMRT en bande C. En bande X, l’augmentation significative des coefficients de diffusion par rapport à la bande C, ne nous permet plus d’ignorer l’extinction du signal. La part occupée par la rétrodiffusion de volume peut dans certaines conditions, devenir la part prépondérante dans la rétrodiffusion totale. Pour terminer, les résultats de la modélisation de couverts de neige sous QCA/DMRT sont validés à l’aide de données RADARSAT-2 et TerraSAR-X. Les deux modèles présentaient des rétrodiffusions totales semblables qui concordaient bien avec les données RADARSAT-2 et TerraSAR-X. Pour RADARSAT-2, le RMSE du modèle QCA/DMRT est de 2,52 dB en HH et 2,92 dB en VV et pour Rayleigh il est de 2,64 dB en HH et 3,01 dB en VV. Pour ce qui est de TerraSAR-X, le RMSE du modèle QCA/DMRT allait de 1,88 dB en HH à 2,32 dB en VV et de 2,20 dB en HH à 2,71 dB en VV pour Rayleigh. Les valeurs de rétrodiffusion totales des deux modèles sont assez similaires. Par contre, les principales différences entre les deux modèles sont bien évidentes dans la répartition des différentes contributions de cette rétrodiffusion totale.

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Guimbretière, Guillaume. "Propagation des vibrations acoustiques dans les matériaux non-cristallins : étude de verres d'oxydes simples." Montpellier 2, 2005. http://www.theses.fr/2005MON20145.

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Kirsch, Philippe Alnot Patrick Assouar Mohamed Badreddine. "Etude et réalisation par lithographie électronique de dispositifs à ondes acoustiques de surface à structure multicouche des filtres pour la bande X aux capteurs de liquide /." S. l. : S. n, 2007. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2007_0125_KIRSCH.pdf.

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Huet, Isabelle. "Elaboration et caractérisation de films minces de LiNbO3 et LiTaO3 en vue de la réalisation de filtres à ondes acoustiques de surface." Montpellier 2, 2001. http://www.theses.fr/2001MON20112.

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Rieutord, François. "Réflectivité et diffraction des rayons X appliquées aux films minces organiques." Paris 11, 1987. http://www.theses.fr/1987PA112384.

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Анотація:

Différentes études par rayon X de films de molécules amphiphiles (monocouche et multicouches de Langmuir-Blodgett) sont ici présentées. On décrit d'abord une méthode d'analyse structurale utilisant trois techniques conjuguées de rayons X: diffraction en transmission et en réflexion, et étude de la réflexion critique. On montre ensuite que l'examen complet d'une courbe de réflectivité aux rayons X permet d'obtenir des informations détaillées non seulement sur la structure mais aussi sur les interfaces de ces films multicouches. Ces données sont complétées par des observations directes des défauts de la surface au moyen de la microscopie électronique sur des répliques. Enfin on étudie la réflectivité d'une monocouche directement à la surface de l'eau, ce qui fournit d'une part son profil suivant la normale et d'autre part la rugosité de l'interface due aux ondes capillaires excitées thermiquement.

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Книги з теми "Ondes X"

télédétection, Centre canadien de. ROS-C/X Aéroporté: Centre Canadien de Télédétection. Capteurs-Imageurs A Micro-Ondes. S.l: s.n, 1988.

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Notebook, Hippo. Notebook: Dream Big for Little Ones - 50 Sheets, 100 Pages - 8 X 10 Inches. Independently Published, 2020.

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Rangel, Ingrid Ribeiro da Gama =. Estágio e Residência Pedagógica: práticas e reflexões. Encontrografia Editora, 2022. http://dx.doi.org/10.52695/978-65-88977-65-1.

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“No processo formativo de professores, o Estágio Curricular Supervisionado pode ser de grande importância. Afinal, trata-se de um espaço onde a articulação efetiva teoria-prática pode ganhar ainda mais evidência. Não em uma articulação esvaziada, mas oriunda de um verdadeiro processo dialético que compreende uma questão como elementar à outra. Nesse contexto, este livro traz algumas práticas e reflexões do Estágio e do Programa de Residência Pedagógica do Instituto Federal Fluminense Campus Campos Centro. Esperamos que a obra fomente outras reflexões sobre estágio docente que nos levem a superar tradicionais dicotomias (como conteúdo X método de ensino, teoria X prática). A formação de professores não deve ocorrer a partir de posicionamentos reducionistas e superficiais, mas de estudos e diálogos que permitam a compreensão do trabalho docente como atividade dialética e socialmente engajada.” Prof.ª Dr.ª Ingrid Ribeiro da Gama Rangel

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notebooks, dorossmix. Book Save Souvenirs: Nice Notebook Journal Gift for Loved Ones 80 Pages, 6 X 9. Independently Published, 2020.

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Sogge, Christopher D. Geodesics and the Hadamard parametrix. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691160757.003.0002.

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This chapter studies the spectrum of Laplace–Beltrami operators on compact manifolds. It begins by defining a metric on an open subset Ω‎ ⊂ Rn, in order to lift their results to corresponding ones on compact manifolds. The chapter then details some elliptic regularity estimates, before embarking on a brief review of geodesics and normal coordinates. The purpose of this review is to show that, with given a particular Laplace–Beltrami operator and any point y0 in Ω‎, one can choose a natural local coordinate system y = κ‎(x) vanishing at y0 so that the quadratic form associated with the metric takes a special form. To conclude, the chapter turns to the Hadamard parametrix.

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Bull, Bull. Notebook: Wwe Rock Bull NeonCollege Ruled 5. 5in X 8. 5in X 128 Pages White Paper Blank Journal Notebook with Black Cover for Family - Friends - and Loved Ones. Independently Published, 2020.

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Bull, Bull. Notebook: Bullshifft Trump Impeachment College Ruled 5. 5in X 8. 5in X 128 Pages White Paper Blank Journal Notebook with Black Cover for Family - Friends - and Loved Ones. Independently Published, 2020.

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Ttichout, Ali. Bige Heart: Nice Notebook Journal Gift for Loved Ones. Black Lined Notebook. 120 Pages. Size 6 X 9 Inshes. Independently Published, 2020.

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Tichout, Ali. Live Your Life: Nice Notebook Journal Gift for Loved Ones. Black Lined Notebook. 120Pages. Size . 6 X 9 Inshes. Independently Published, 2020.

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Notebook, popohamham's Football Coaching. Football Coach NOTEBOOK: Nice Notebook Journal Gift for Loved Ones, Blank Lined Notebook, 120 Pages, Size 6 X 9. Independently Published, 2020.

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Частини книг з теми "Ondes X"

Spârchez, Zeno. "The Separation of Spherical Shape Powder Particles from the Non-Spherical Ones." In Materials and Technologies, 87–90. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-460-x.87.

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Dudás, Zoltán. "Comparison of Measured Phase Volumes with Calculated ones Created by TTT-CCT Diagram Transformation." In Materials Science Forum, 497–504. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-426-x.497.

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Block, E. "From 5-Sulfanylated Pentan-2-ones or 5-Bromopentan-2-ones." In Ene-X Compounds (X=S, Se, Te, N, P), 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-033-00221.

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Block, E. "Synthesis from 1,4-Dien-3-ones and 1-En-4-yn-3-ones by Michael Addition." In Ene-X Compounds (X=S, Se, Te, N, P), 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-033-00274.

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Block, E. "Synthesis from 5-Substituted Pentan-2-ones." In Ene-X Compounds (X=S, Se, Te, N, P), 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-033-00220.

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Carretero, J. C., and R. G. Arrayás. "S-Oxidation of Isothiazol-3(2)-ones." In Ene-X Compounds (X=S, Se, Te, N, P), 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-033-00048.

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Block, E. "Synthesis from 3-Methyl-6-sulfanylhexan-2-ones." In Ene-X Compounds (X=S, Se, Te, N, P), 1. Georg Thieme Verlag KG, 2007. http://dx.doi.org/10.1055/sos-sd-033-00283.

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List, B., C. Chandler, R. R. Torres, and A. Erkkilä. "Synthesis of Oxazol-2(3)-ones." In X-Ene-X (X=F, Cl, Br, I, O, S, Se, Te, N, P), Ene-Hal, and Ene-O Compounds, 1. Georg Thieme Verlag KG, 2008. http://dx.doi.org/10.1055/sos-sd-032-00298.

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Parente, Carlos Eduardo, Izabel Christina Martins Nogueira, Renato Parkinson Martins, and Eric Oliveira Ribeiro. "CLIMATOLOGIA DE ONDAS." In Meteorologia e Oceanografia, 55–98. Elsevier, 2015. http://dx.doi.org/10.1016/b978-85-352-6208-7.50009-x.

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Baader, W. J., and E. L. Bastos. "1,2,4-Trioxan-5-ones from α-(Trimethylsilylperoxy) Esters." In Peroxides, Inorganic Esters (RO-X, X=Hal, S, Se, Te, N), 1. Georg Thieme Verlag KG, 2009. http://dx.doi.org/10.1055/sos-sd-038-00439.

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Тези доповідей конференцій з теми "Ondes X"

Moretti, P., A. P. Ferreira, and F. P. P. Leite. "O EFEITO DE EXPOSIÇÃO ÀS ONDAS SOBRE A DISTRIBUIÇÃO VERTICAL DE PERACARIDA ASSOCIADA À COMUNIDADE BOSTRYCHIETUM EM PRAIA DO LITORAL NORTE DO ESTADO DE SÃO PAULO." In X Congresso Brasileiro sobre Crustáceos. Sociedade Brasileira de Carcinologia, 2018. http://dx.doi.org/10.21826/2178-7581x2018064.

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Gruev, Dmitrii I., and Vladimir A. Arkadiev. "Computer simulation of quasiparallel x-ray beams transforming into convergent ones by means of Kumakhov semilens." In SPIE's 1995 International Symposium on Optical Science, Engineering, and Instrumentation, edited by Richard B. Hoover and Arthur B. C. Walker, Jr. SPIE, 1995. http://dx.doi.org/10.1117/12.212581.

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Tavares, Jacimar F., Regina Braga, José Maria N. David, Marco Antônio P. Araújo, and Fernanda Campos. "GiveMe Metrics - Um Framework Conceitual para Extração de Dados Históricos sobre Evolução de Software." In X Simpósio Brasileiro de Sistemas de Informação. Sociedade Brasileira de Computação - SBC, 2014. http://dx.doi.org/10.5753/sbsi.2014.6100.

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Este artigo apresenta um framework conceitual constituído por ferramentas capazes de extrair dados históricos sobre evolução de software de repositórios de código fonte, de defeitos e de processos de desenvolvimento de software. As ferramentas que compõem o framework foram obtidas em um processo de mapeamento sistemático. Uma prova de conceito foi realizada onde foram extraídos dados sobre defeitos em projetos do SINAPAD (Sistema Nacional de Processamento de AltoDesempenho) que possui projetos na área da computação. Também foi realizada a análise dos dados extraídos, objetivando responder algumas questões relevantes para o projeto. Ao final, foi possível avaliar a utilização do framework GiveMe Metrics (GMM) na extração de dados sobre defeitos.

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Coutinho, Henrique Guimarães. "Desenvolvimento de Estratégia de Geolocalização Bidimensional com Base em Ondas Sonoras." In Congresso Latino-Americano de Software Livre e Tecnologias Abertas. Sociedade Brasileira de Computação - SBC, 2021. http://dx.doi.org/10.5753/latinoware.2021.19907.

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O presente trabalho visou aferir a posição de um objeto emissor de ondas sonoras a partir da criação de um sistema automatizado capaz de apontar o ponto onde está posto do objeto principal. O projeto de pesquisa se insere no contexto da demanda do grupo de foguetemodelismo da Universidade Federal do ABC, Rocket Design, de possuir uma nova forma de análise da trajetória de seus foguetes durante seus lançamentos, e poder, a partir dela, extrair informações importantes como a velocidade e aceleração de lançamento. Além disso, o projeto fundamenta métodos de utilizar placas de desenvolvimento para a aplicação em problemas de engenharia. Em termos específicos, o projeto visou o desenvolvimento de um sistema automatizado capaz de medir a posição de um objeto em um plano 2D através da aferição do intervalo de tempo de demora para a onda sonora percorrer um determinado espaço. O objeto de estudo possuiu um emissor de som e utilizou a técnica de triangulação por latência de tempo de diferença de chegada (TDoA – Time Difference of Arrival) para a determinação da posição do objeto através de diversos sensores sonoros ao redor do objeto principal. Para a conquista do objetivo, criou-se um sensor com Arduino capaz de captar ondas sonoras em forma de tensão de entrada para posterior análise, assim como um sensor capaz de captar a temperatura ambiente do meio de testes. A coleta definitiva de som pôde ser realizada e a posição de emissor de ondas sonoras bidimensionalmente aferida através da criação de um código de varredura, capaz de apontar a posição do emissor de ondas sonoras com base na temperatura ambiente e diferença de tempos de chegada entre pares de sensores. A partir da criação de um código de gabarito das posições dos componentes, consolidou-se os meios de executar a comparação entre os dados colhidos com a realidade. Portanto, os resultados captados pelo sensor foram que a posição encontrada para o emissor de ondas esteve entre 42 centímetros e 2 metros afastada da posição real dele, em um plano de testes de 10,93 x 2,90 metros. A partir dos resultados colhidos, ainda retomou-se a literatura para a investigação dos fatores limitantes para o desenvolvimento de um sistema de melhor acurácia e precisão. O sistema ainda poderia ser expandido para um panorama dinâmico: ao se analisar posições consecutivas da trajetória de um objeto se poderá extrair informações da cinemática do objeto. Em estudos futuros, mediante aprimoramento do sensor utilizado, seria possível retornar pontos da trajetória de foguetes da equipe Rocket Design em seus lançamentos e, dessa forma, poderá, então, executar melhorias estruturais para otimização de tais valores.

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Pinto, Weslei, Eduardo Guerra, Gerson Neto, and Phyllipe Lima. "Ferramenta de controle de acesso baseado em gamificação." In X Conferência Brasileira de Software: Teoria e Prática. Sociedade Brasileira de Computação - SBC, 2019. http://dx.doi.org/10.5753/cbsoft_estendido.2019.7669.

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Aplicações que usam gamificação desbloqueiam novas funcionalidades conforme o usuário obtém conquistas ou atinge certa pontuação. Porém, fazer o controle do acesso integrado a estes conceitos se torna uma atividade complexa, e sua implementação tende a acontecer isoladamente nos métodos das classes de negócio, aumentando o acoplamento entre as regras de negócio e de controle de acesso. Este artigo apresenta uma ferramenta que integra as funcionalidades de controle de acesso oferecidas pelo framework Guardian aos mecanismos de gamificação oferecido pelo framework Esfinge Gamification. A avaliação da ferramenta foi feita com um estudo de caso de uma aplicação web de fórum, onde são implementadas restrições de acesso baseadas no mecanismo de gamificação.

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De Stefano, V., G. Leone, R. Ferrelli, and B. Bizzi. "A NEW VARIANT OF FACTOR X DEFICIENCY (FACTOR X ROMA)." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643296.

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A 13 years-old-girl was admitted in our Hospital for a large muscle hematoma of left psoas. At age 3 she had a severe tonsillar bleeding following angina. Afterwards she suffered from easy bruisability and recurrent epistaxis. Prothrombin time (PT) was slightly prolonged (14.7 sec, control 12 sec, INR 1.5), while a more marked prolongation in aPTT was noticed (54.7 sec, control 30.3 sec). All clotting factors resulted within the normal range but Factor X. Factor X antigen was 0.95 U/ml (Laurell), whereas Factor X activity was 0.52 U/ml by extrinsic system assay (rabbit brain and lung thromboplastin), 0.06 U/ml by intrinsic system assay (rabbit brain cephalin) and 1.15 U/ml by activation by RW-cephalin. Chromogenic assays (S-2222 and CBS 3139) perfor med after activation with RW gave 1.02 U/ml and 1.00 U/ml, respectively. The patient plasma had no inhibitory activity against Factor X. The parents of the proposita (first cousins) had Factor X antigen levels and RW functional activity around 1.00 U/ ml, whereas Factor X activity tested by extrinsic and intrinsic system assay was about 0.60 U/ml and 0.50 U/ml, respectively. This Factor X variant seems different from the other ones previously described, showing normal antigen levels and RW activation, a severe defect in the intrinsic activation and only a partial defect in the extrinsic activation. In particular the two defects more close to it (Factor X Friuli and Factor X Melbourne), both found in patients with Italian ancestry, were dif ferent because of a very prolonged PT (Factor X Friuli) or a normal PT (Factor X Melbourne).

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Aldeia, Guilherme, and Fabrício França. "Um Estudo Paramétrico do Algoritmo Evolutivo baseado na representação Interação-Transformação para Regressão Simbólica." In Simpósio Brasileiro de Sistemas de Informação. Sociedade Brasileira de Computação (SBC), 2020. http://dx.doi.org/10.5753/sbsi.2020.13138.

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Dada uma base de dados com variáveis explanatórias x e uma variável alvo y, onde exista uma função desconhecida f(x) = y, a regressão simbólica busca por uma função f(x) que se aproxime suficientemente bem de f(x). Ela costuma ser feita por meios da programação genética, um método de busca e otimização que simula conceitos da teoria da evolução para construir e ajustar ˆf(x) através da manipulação de populações de soluções, mas a forma em que as soluções são expressas (por meio de árvores sintáticas) apresenta um espaço de busca amplo e resultados pouco interpretáveis. Nesse contexto, foi introduzida recentemente uma nova representação para a regressão simbólica — a Interação-Transformação (IT) — de forma a evitar esses problemas, limitando o espaço de busca em expressões simples, sendo capaz de retornar resultados com maior interpretabilidade que se mantem competitivos com a literatura. Algoritmos de regressão simbólica apresentam um importante compromisso entre aproximação dos dados e complexidade da função encontrada. Essa representação foi usada no contexto de um algoritmo evolutivo, com a finalidade de encontrar expressões concisas que tenham um erro de aproximação pequeno e resultados competitivos com a literatura. Em [Aldeia and de França 2020], os autores investigaram a influência dos hiper-parâmetros do algoritmo evolutivo proposto sobre os resultados, em termos de erro de aproximação e complexidade da função simbólica encontrada. Os resultados mostraram que o número máximo de termos ´ e mais importante que o limite de expoentes permitido, e existe um limite onde aumentar o tamanho da expressão gera benefícios, podendo ser explicado pelo overfit. Como o limite dos expoentes tem menor influência, ele pode ter um valor definido como padrão sem impactar nos resultados, mas diminuindo a complexidade das funções em termos de sua interpretabilidade.

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Maglich, Bogdan C., and Orhan Nalcioglu. "‘ONCOSENSOR’ for Noninvasive High-Specificity Breast Cancer Diagnosis by Carbogen-Enhanced Neutron Femto-Oximetry." In ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13295.

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Based on the first experiment on Differential Femto Oximetry (Paper 13270), we conducted a computer simulated study of the feasibility of conceptual design for our noninvasive malignancy probe, Oncosensor, to diagnose hypoxia of malignancy M = −0.90, measured by pO2 — which correspond to volume averaged hypoxia M′ = −0.09 — in 1cm, 3 cm and 5 cm DIA tumors embedded in the middle of a 10 cm DIA breast. M′ is further masked by background γ’s from the in vivo tissue by factor x = 4.4–7 for subcutaneous and central tumor, respectively, to apparent M″ = M′/X which, in turn, renders hypoxia non-diagnosable for 1 cm tumors; marginally so for 3 cm ones with specificity S = 75%, and fully diagnosable with S = 95% in 5 cm ones. To diagnose 1–3 cm and smaller tumors, we propose to enhance M″ by a factor of ≈ 3 by replacing air breathing with that of Carbogen (O2 95%, CO2 5%). With carbogen breathing, simulations predict hypoxia detection in 1 cm subcutaneous tumor with S = 68%, and in 3 cm ones with S = 95–99.9%. Carbogen renders possible 2 additional diagnostic tests for redundancy. Significant improvements of the above measurement accuracies are projected. Oncosensor will be tested in vivo with R3230 tumors in Fischer rats at UCI’s Center for Functional Onco-Imaging. Oncosensor requires imaging guidance.

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Asadizanjani, Navid, Sina Shahbazmohamadi, Mark Tehranipoor, and Domenic Forte. "Non-Destructive PCB Reverse Engineering Using X-Ray Micro Computed Tomography." In ISTFA 2015. ASM International, 2015. http://dx.doi.org/10.31399/asm.cp.istfa2015p0164.

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Abstract Reverse engineering of electronics systems is performed for various reasons ranging from honest ones such as failure analysis, fault isolation, trustworthiness verification, obsolescence management, etc. to dishonest ones such as cloning, counterfeiting, identification of vulnerabilities, development of attacks, etc. Regardless of the goal, it is imperative that the research community understands the requirements, complexities, and limitations of reverse engineering. Until recently, the reverse engineering was considered as destructive, time consuming, and prohibitively expensive, thereby restricting its application to a few remote cases. However, the advents of advanced characterization and imaging tools and software have counteracted this point of view. In this paper, we show how X-ray micro-tomography imaging can be combined with advanced 3D image processing and analysis to facilitate the automation of reverse engineering, and thereby lowering the associated time and cost. In this paper, we demonstrate our proposed process on two different printed circuit boards (PCBs). The first PCB is a four-layer custom designed board while the latter is a more complex commercial system. Lessons learned from this effort can be used to both develop advanced countermeasures and establish a more efficient workflow for instances where reverse engineering is deemed necessary. Keywords: Printed circuit boards, non-destructive imaging, X-ray tomography, reverse engineering.

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Antunes, Carlos. "Proceedings of X Iberian Symposium on the Minho River Hydrographic Basin." In X Iberian Symposium on the Minho River Hydrographic Basin, edited by Patrício Bouça, Mónica Caldas, Tânia Rodrigues, Irene Pinheiro, Dimítri Costa, and Nuno Gomes. Environmental Smoke, 2021. http://dx.doi.org/10.32435/envsmoke/xibesymp-book.

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No X Simpósio Ibérico Sobre a Bacia Hidrográfica do Rio Minho, organizado pelo Aquamuseu do Rio Minho/Câmara Municipal de Vila Nova de Cerveira (Portugal) e co-organizado pelo Centro Interdisciplinar de Investigação Marinha e Ambiental – Universidade do Porto, foram abordados os temas que abrangeram áreas desde a geoquímica de sedimentos e formas erosivas do leito rochoso do rio Minho; as mudanças climáticas numa perspetiva da futura gestão da água e nos efeitos já evidentes ao nível das comunidades biológicas; importância da gestão dos recursos da pesca no rio Mouro pela monitorização e aplicação de regras específicas de exploração; diagnóstico e medidas em curso para a conservação das populações de peixes migradores; a ameaça dos poluentes emergentes; a divulgação de novos registos de invertebrados encontrados no rio Minho (abordagem taxonómica); evidências da colaboração entre pescadores e investigadores para um melhor conhecimento social da comunidade piscatória, da sua atividade e da sua contribuição para o processo de gestão; comunicação de ciência e educação ambiental. No âmbito da mesa-redonda (workshop), em modelo aberto à comunidade, onde participaram pescadores, foram apresentados resultados de trabalhos no âmbito do Conhecimento Ecológico Local (Etnobiologia), em que os próprios tiveram a oportunidade de manifestar as suas opiniões relacionadas com a atividade da pesca. Houve ainda oportunidade de entregar os prémios referentes ao concurso de ilustração científica “Rio Minho, Biodiversidade e Artes de Pesca”, cuja exposição completa esteve patente na Bienal de Cerveira.

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Звіти організацій з теми "Ondes X"

Perl-Treves, Rafael, M. Kyle, and Esra Galun. Development and Application of a Molecular Genetic Map for Melon (Cucumis melo). United States Department of Agriculture, October 1993. http://dx.doi.org/10.32747/1993.7568094.bard.

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This project has generated a systematic survey of DNA polymorphism in Cucumis melo. An RFLP and RAPD survey of the major cultivar groups and botanical varieties of this species has been conducted, with the purpose of assessing the degree of molecular variation and phylogenetic relationships within the melon germplasm and, at the same time, develop sets of markets suitable for mapping the melon genome. Additional activities regarding variation in the melon germplasm in fruit traits and regeneration ability have been initiated as well. The necessary populations required for the development of a molecular map of the C. melo genome have been prepared. An F2 that segregated for 4 viral resistances, powdery mildew resitance and sex type has been derived from a PI 414723 x Topmark cross, and a RILs population has been prepared from it. We have confirmed the resistances in the population and have analyzed the genetic relationships between these resistances. Progress toward the construction of a molecular map of C. melo and the development of markers linked to those traits is described. We have so far screened the first few tens of markers in the F2 population, and many additional ones were screened in DNA bulks prepared from such population.

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Ficht, Thomas, Gary Splitter, Menachem Banai, and Menachem Davidson. Characterization of B. Melinensis REV 1 Attenuated Mutants. United States Department of Agriculture, December 2000. http://dx.doi.org/10.32747/2000.7580667.bard.

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Brucella Mutagenesis (TAMU) The working hypothesis for this study was that survival of Brucella vaccines was directly related to their persistence in the host. This premise is based on previously published work detailing the survival of the currently employed vaccine strains S19 and Rev 1. The approach employed signature-tagged mutagenesis to construct mutants interrupted in individual genes, and the mouse model to identify mutants with attenuated virulence/survival. Intracellular survival in macrophages is the key to both reproductive disease in ruminants and reticuloendothelial disease observed in most other species. Therefore, the mouse model permitted selection of mutants of reduced intracellular survival that would limit their ability to cause reproductive disease in ruminants. Several classes of mutants were expected. Colonization/invasion requires gene products that enhance host-agent interaction or increase resistance to antibacterial activity in macrophages. The establishment of chronic infection requires gene products necessary for intracellular bacterial growth. Maintenance of chronic infection requires gene products that sustain a low-level metabolism during periods characterized little or no growth (1, 2). Of these mutants, the latter group was of greatest interest with regard to our originally stated premise. However, the results obtained do not necessarily support a simplistic model of vaccine efficacy, i.e., long-survival of vaccine strains provides better immunity. Our conclusion can only be that optimal vaccines will only be developed with a thorough understanding of host agent interaction, and will be preferable to the use of fortuitous isolates of unknown genetic background. Each mutant could be distinguished from among a group of mutants by PCR amplification of the signature tag (5). This approach permitted infection of mice with pools of different mutants (including the parental wild-type as a control) and identified 40 mutants with apparently defective survival characteristics that were tentatively assigned to three distinct classes or groups. Group I (n=13) contained organisms that exhibited reduced survival at two weeks post-infection. Organisms in this group were recovered at normal levels by eight weeks and were not studied further, since they may persist in the host. Group II (n=11) contained organisms that were reduced by 2 weeks post infection and remained at reduced levels at eight weeks post-infection. Group III (n=16) contained mutants that were normal at two weeks, but recovered at reduced levels at eight weeks. A subset of these mutants (n= 15) was confirmed to be attenuated in mixed infections (1:1) with the parental wild-type. One of these mutants was eliminated from consideration due to a reduced growth rate in vitro that may account for its apparent growth defect in the mouse model. Although the original plan involved construction of the mutant bank in B. melitensis Rev 1 the low transformability of this strain, prevented accumulation of the necessary number of mutants. In addition, the probability that Rev 1 already carries one genetic defect increases the likelihood that a second defect will severely compromise the survival of this organism. Once key genes have been identified, it is relatively easy to prepare the appropriate genetic constructs (knockouts) lacking these genes in B. melitensis Rev 1 or any other genetic background. The construction of "designer" vaccines is expected to improve immune protection resulting from minor sequence variation corresponding to geographically distinct isolates or to design vaccines for use in specific hosts. A.2 Mouse Model of Brucella Infection (UWISC) Interferon regulatory factor-1-deficient (IRF-1-/- mice have diverse immunodeficient phenotypes that are necessary for conferring proper immune protection to intracellular bacterial infection, such as a 90% reduction of CD8+ T cells, functionally impaired NK cells, as well as a deficiency in iNOS and IL-12p40 induction. Interestingly, IRF-1-/- mice infected with diverse Brucella abortus strains reacted differently in a death and survival manner depending on the dose of injection and the level of virulence. Notably, 50% of IRF-1-/- mice intraperitoneally infected with a sublethal dose in C57BL/6 mice, i.e., 5 x 105 CFU of virulent S2308 or the attenuated vaccine S19, died at 10 and 20 days post-infection, respectively. Interestingly, the same dose of RB51, an attenuated new vaccine strain, did not induce the death of IRF-1-/- mice for the 4 weeks of infection. IRF-1-/- mice infected with four more other genetically manipulated S2308 mutants at 5 x 105 CFU also reacted in a death or survival manner depending on the level of virulence. Splenic CFU from C57BL/6 mice infected with 5 x 105 CFU of S2308, S19, or RB51, as well as four different S2308 mutants supports the finding that reduced virulence correlates with survival Of IRF-1-/- mice. Therefore, these results suggest that IRF-1 regulation of multi-gene transcription plays a crucial role in controlling B. abortus infection, and IRF-1 mice could be used as an animal model to determine the degree of B. abortus virulence by examining death or survival. A3 Diagnostic Tests for Detection of B. melitensis Rev 1 (Kimron) In this project we developed an effective PCR tool that can distinguish between Rev1 field isolates and B. melitensis virulent field strains. This has allowed, for the first time, to monitor epidemiological outbreaks of Rev1 infection in vaccinated flocks and to clearly demonstrate horizontal transfer of the strain from vaccinated ewes to unvaccinated ones. Moreover, two human isolates were characterized as Rev1 isolates implying the risk of use of improperly controlled lots of the vaccine in the national campaign. Since atypical B. melitensis biotype 1 strains have been characterized in Israel, the PCR technique has unequivocally demonstrated that strain Rev1 has not diverted into a virulent mutant. In addition, we could demonstrate that very likely a new prototype biotype 1 strain has evolved in the Middle East compared to the classical strain 16M. All the Israeli field strains have been shown to differ from strain 16M in the PstI digestion profile of the omp2a gene sequence suggesting that the local strains were possibly developed as a separate branch of B. melitensis. Should this be confirmed these data suggest that the Rev1 vaccine may not be an optimal vaccine strain for the Israeli flocks as it shares the same omp2 PstI digestion profile as strain 16M.

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